0001437749-24-008872 | 10-K | XBRL Viewer

Schedule of Maturities of Long-Term Debt [Table Text Block]

2024	$	2,000
2025		21,580
2026		2,000
2027		167
Thereafter		0
Total	$	25,747

Note 3 - Supplemental Balance Sheet Information

12 Months Ended

Dec. 31, 2023

Supplemental Balance Sheet Disclosures [Text Block]

Note 3 - Supplemental Balance Sheet Information

a.	Cash and Restricted Cash

The Company had cash and restricted cash totaling $10,278 and $5,713 as of December 31, 2023 and 2022, respectively.

	December 31,
	2023		2022
Cash	$	10,196	$	5,634
Restricted cash		82		79
Total	$	10,278	$	5,713

As of December 31, 2023 and December 31, 2022, restricted cash included $82 and $79, respectively, of euro-denominated deposits withheld by the Dutch tax authorities and third-party VAT representatives in connection with a previously utilized logistics arrangement in the Netherlands. Restricted cash is included as a component of the cash balance for purposes of the consolidated statements of cash flows.

b.	Inventory, Net

Inventories are stated at the lower of cost or net realizable value with cost determined under the first-in, first-out (FIFO) method. The composition of inventories, net was:

	December 31,
	2023		2022
Raw materials	$	29,098	$	29,200
Work in process		3,187		2,757
Finished products		9,930		9,235
Total	$	42,215	$	41,192

c.	Property, Plant and Equipment

Major classes of property, plant and equipment consisted of the following:

	December 31,
	2023			2022
Land	$	1,273		$	1,273
Buildings and leasehold improvements		15,998			15,572
Machinery and equipment		57,584			63,981
Furniture and fixtures		2,845			2,845
Computer hardware and software		7,868			7,744
Construction in progress		2,033			1,245
		87,601			92,660
Less: Accumulated depreciation		(66,484	)		(70,944	)
Total	$	21,117		$	21,716

Depreciation expense was $3,022 and $3,177 for the years ended December 31, 2023 and 2022, respectively.

d.	Goodwill and Other Intangible Assets

The Company conducted its annual impairment test for goodwill and other indefinite-lived intangible assets as of October 1, 2023. We identified two (2) goodwill reporting units and five (5) indefinite-lived intangible assets. We performed a quantitative impairment assessment of each goodwill reporting unit and indefinite-lived intangible asset. Based on the results of our quantitative impairment tests, and consideration of qualitative factors as of our test date and December 31, 2023, no impairment was identified.

The following table summarizes the goodwill activity by segment for the years ended December 31, 2023 and 2022:

	Battery & Energy Products		Communications Systems		Total
Balance – January 1, 2023	$	25,935	$	11,493	$	37,428
Effect of foreign currency translation		143		-		143
Balance – December 31, 2023	$	26,078	$	11,493	$	37,571

The composition of intangible assets was:

	December 31, 2023
	Cost		Accumulated amortization		Net
Customer relationships	$	13,092	$	6,656	$	6,436
Patents and technology		5,606		5,322		284
Trade names		4,647		647		4,000
Trademarks		3,402		-		3,402
Other		1,500		515		985
Total other intangible assets	$	28,247	$	13,140	$	15,107

	December 31, 2022
	Cost		Accumulated amortization		Net
Customer relationships	$	12,970	$	5,992	$	6,978
Patents and technology		5,557		5,171		386
Trade names		4,629		522		4,107
Trademarks		3,404		-		3,404
Other		1,500		454		1,046
Total other intangible assets	$	28,060	$	12,139	$	15,921

The change in the cost value of other intangible assets is attributable to the effect of foreign currency translations.

Amortization of other intangible assets was included in the following financial statement captions:

	Year ended December 31,
	2023		2022
Research and development expense	$	97	$	97
Selling, general and administrative expense		792		1,185
Total	$	889	$	1,282

Future amortization expense of amortizable intangible assets will be approximately $912, $912, $775, $775 and $774 for the five fiscal years ending December 31, 2024 through 2028, respectively.

Note 7 - Operating Leases (Details Textual)	Dec. 31, 2023
Minimum [Member]
Lessee, Operating Lease, Remaining Lease Term (Year)	1 year
Maximum [Member]
Lessee, Operating Lease, Remaining Lease Term (Year)	9 years

Note 7 - Operating Leases - Future Minimum Lease Payments (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
2024	$ 894
2025	698
2026	624
2027	644
Lessee, Operating Lease, Liability, to be Paid, Year Five	648
Thereafter	463
Total lease payments	3,971
Less: Imputed interest	(433)
Accrued Expenses and Other Current Liabilites and Other Noncurrent Liabilities [Member]
Present value of remaining lease payments	$ 3,538	$ 2,202

Note 3 - Supplemental Balance Sheet Information - Composition of Intangible Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Cost	$ 28,247	$ 28,060
Accumulated amortization	13,140	12,139
Net	15,107	15,921
Customer Relationships [Member]
Cost	13,092	12,970
Accumulated amortization	6,656	5,992
Net	6,436	6,978
Patented Technology [Member]
Cost	5,606	5,557
Accumulated amortization	5,322	5,171
Net	284	386
Trade Names [Member]
Cost	4,647	4,629
Accumulated amortization	647	522
Net	4,000	4,107
Trademarks [Member]
Cost	3,402	3,404
Accumulated amortization	0	0
Net	3,402	3,404
Other Intangible Assets [Member]
Cost	1,500	1,500
Accumulated amortization	515	454
Net	$ 985	$ 1,046

Note 1 - Summary of Operations and Significant Accounting Policies 2 (Details Textual) - Extended Warranty Contracts [Member] $ in Thousands	Dec. 31, 2023 USD ($)
Revenue, Remaining Performance Obligation, Amount	$ 1,407
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Amount	$ 287
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Revenue, Remaining Performance Obligation, Amount	$ 1,120
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year

Note 5 - Stock-based Compensation - Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Shares under option, beginning of period (in shares)	1,425,693	1,306,824
Options outstanding - weighted average exercise price (in dollars per share)	$ 6.72	$ 6.87
Options granted (in shares)	231,650	289,950
Options granted (in dollars per share)	$ 6.69	$ 5.42
Options exercised (in shares)	(254,393)	(59,500)
Options exercised (in dollars per share)	$ 5.83	$ 3.82
Options forfeited or expired (in shares)	(152,355)	(111,581)
Options forfeited or expired (in dollars per share)	$ 5.06	$ 6.56
Shares under option, end of period (in shares)	1,250,595	1,425,693
Options outstanding - weighted average exercise price (in dollars per share)	$ 7.1	$ 6.72
Options outstanding - weighted average remaining contractual term (Year)	3 years 11 months 19 days
Options exercisable – aggregate intrinsic value (in shares)	789,209	881,804
Options outstanding - aggregate intrinsic value	$ 515
Options exercisable – weighted average exercise price (in dollars per share)	$ 7.56	$ 7.13
Vested and Expected to Vest (in shares)	1,151,228
Options vested and expected to vest - weighted average exercise price (in dollars per share)	$ 7.17
Options vested and expected to vest - weighted average remaining contractual term (Year)	3 years 9 months 14 days
Options vested and expected to vest - aggregate intrinsic value	$ 452
Options exercisable – weighted average remaining contractual term (Year)	2 years 8 months 8 days
Options exercisable - aggregate intrinsic value	$ 241

Note 7 - Operating Leases (Tables)

12 Months Ended

Dec. 31, 2023

Lease, Cost [Table Text Block]

	Year ended December 31,
	2023		2022
Operating lease cost	$	1,016	$	894
Variable lease cost		114		95
Total lease cost	$	1,130	$	989

Lessee, Lease, Cash Flow Information [Table Text Block]

	Year ended December 31,
	2023		2022
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$	1,036	$	908
Right-of-use assets obtained in exchange for lease liabilities:	$	2,192	$	476

Lessee, Lease, Balance Sheet Information [Table Text Block]

		December 31,
	Balance Sheet Classification	2023			2022
Assets:
Operating lease right-of-use asset	Other noncurrent assets	$	3,589		$	2,187

Liabilities:
Current operating lease liability	Accrued expenses and other current liabilities	$	894		$	895
Operating lease liability, net of current portion	Other noncurrent liabilities		2,644			1,307
Total operating lease liability		$	3,538		$	2,202

Weighted-average remaining lease term (years)			5.3			4.7

Weighted-average discount rate			4.5	%		4.5	%

Lessee, Operating Lease, Liability, to be Paid, Maturity [Table Text Block]

Maturity of Operating Lease Liabilities
2024	$	894
2025		698
2026		624
2027		644
2028		648
Thereafter		463
Total lease payments	$	3,971
Less: Imputed interest		(433	)
Present value of remaining lease payments	$	3,538

Note 4 - Commitments and Contingencies

12 Months Ended

Dec. 31, 2023

Commitments and Contingencies Disclosure [Text Block]

Note 4 - Commitments and Contingencies

a.	Legal Matters

We are subject to legal proceedings and claims that arise from time to time in the ordinary course of business. We believe that the final disposition of any such matters of which we are currently aware will not have a material adverse effect on the Company’s financial position, results of operations or cash flows. However, recognizing that legal matters are subject to inherent uncertainties, there exists the possibility that ultimate resolution of current or future legal matters could have a material adverse impact on the Company’s financial position, results of operations or cash flows. We are not aware of any such situations at this time.

b.	Indemnity

Our organizational documents provide that our directors or officers will be reimbursed for all expenses, to the fullest extent permitted by law arising out of their performance.

c.	Purchase Commitments

As of December 31, 2023, we have made commitments to purchase approximately $890 of production machinery and equipment.

China

Our operating facility in China presents risks including, but not limited to, changes in local regulatory requirements, changes in labor laws, local wage laws, environmental regulations, taxes and operating licenses, compliance with U.S. regulatory requirements, including the Foreign Corrupt Practices Act, uncertainties as to application and interpretation of local laws and enforcement of contract and intellectual property rights, currency restrictions, currency exchange controls, fluctuations of currency, and currency revaluations, eminent domain claims, civil unrest, power outages, water shortages, labor shortages, labor disputes, increase in labor costs, rapid changes in government, economic and political policies, political or civil unrest, acts of terrorism, or the threat of boycotts, other civil disturbances and the possible impact of the imposition of tariffs by the U.S. Government on 9 Volt batteries that we manufacture in China as well as any retaliating trade policies or restrictions. Any such disruptions could depress our earnings and have other material adverse effects on our business, financial condition and results of operations.

e.	Product Warranties

We typically offer standard warranties against product defects that range from ninety (90) days to three (3) years from the date of purchase. We also offer separately priced extended warranty contracts on certain products. Warranty costs expected to be incurred are estimated based on the Company’s experience and recorded as costs of products sold. Standard warranty costs are recognized upon product sale. Extended warranty costs are recognized over the term of the contract.

	2023			2022
Accrued warranty obligations – beginning	$	323		$	133
Accruals for warranties issued		458			287
Settlements made		(234	)		(97	)
Accrued warranty obligations - ending	$	547		$	323

Note 5 - Stock-based Compensation (Details Textual) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Jul. 31, 2021	Jun. 30, 2014
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number	1,250,595	1,425,693	1,306,824
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 3.48	$ 2.55
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period, Intrinsic Value	$ 556	$ 88
Proceeds from Stock Options Exercised	$ 1,248	$ 116
Common Stock, Capital Shares Reserved for Future Issuance	632,593
Share-Based Payment Arrangement, Option [Member]
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 844
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition	1 year 6 months
Restricted Stock [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized	4,029
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number	27
The 2014 Long-term Incentive Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized				2,750,000	1,750,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number	1,250,595
The 2014 Long-term Incentive Plan [Member] \| Awards Other than Stock Options and SARs [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized					800,000
The 2014 Long-term Incentive Plan [Member] \| Restricted Stock [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)	3 years

Note 7 - Operating Leases - Supplemental Balance Sheet Information Related to Leases (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Weighted-average remaining lease term (years) (Year)	5 years 3 months 18 days	4 years 8 months 12 days
Weighted-average discount rate	4.50%	4.50%
Other Noncurrent Assets [Member]
Operating lease right-of-use asset	$ 3,589	$ 2,187
Accrued Expenses and Other Current Liabilities [Member]
Current operating lease liability	894	895
Other Noncurrent Liabilities [Member]
Operating lease liability, net of current portion	2,644	1,307
Accrued Expenses and Other Current Liabilites and Other Noncurrent Liabilities [Member]
Total operating lease liability	$ 3,538	$ 2,202

Note 6 - Income Taxes - Income Tax Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
State	$ 27	$ 19
Foreign	623	617
Current Income Tax Expense (Benefit)	650	636
Federal	1,466	(661)
Foreign	(165)	(301)
Deferred Income Tax Expense (Benefit)	1,301	(962)
Total income tax (benefit) provision	$ 1,951	$ (326)

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References + Details

Note 7 - Operating Leases - Supplement Cash Flow Information Related to Leases (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Operating cash flows from operating leases	$ 1,036	$ 908
Right-of-use assets obtained in exchange for lease liabilities:	$ 2,192	$ 476

Note 6 - Income Taxes (Tables)

12 Months Ended

Dec. 31, 2023

Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]

	Year ended December 31,
	2023			2022
Current:
State	$	27		$	19
Foreign		623			617
		650			636
Deferred:
Federal		1,466			(661	)
Foreign		(165	)		(301	)
		1,301			(962	)
Total income tax (benefit) provision	$	1,951		$	(326	)

Schedule of Deferred Tax Assets and Liabilities [Table Text Block]

	December 31,
	2023			2022
Deferred tax assets:
Net operating loss carryforwards	$	8,515		$	11,460
Research and development		3,536			2,812
Tax credit carryforwards		2,898			2,600
Accrued expenses, reserves and other		2,909			2,419
Intangible assets		1,596			1,521
Total deferred tax assets		19,454			20,812
Valuation allowance for deferred tax assets		(2,441	)		(2,416	)
Net deferred tax assets		17,013			18,396

Deferred tax liabilities:
Intangible assets		(8,095	)		(8,176	)
Accrued expenses, reserves and other		(65	)		(68	)
Total deferred tax liabilities		(8,160	)		(8,244	)

Net deferred tax assets	$	8,853		$	10,152

Schedule of Net Deferred Tax Liabilities [Table Text Block]

	December 31,
	2023			2022

Deferred tax assets, net	$	10,567		$	12,069
Deferred tax liabilities		(1,714	)		(1,917	)
	$	8,853		$	10,152

Schedule of Income before Income Tax, Domestic and Foreign [Table Text Block]

	Year ended December 31,
	2023		2022
United States	$	7,294	$	(2,771	)
Foreign		1,823		2,325
	$	9,117	$	(446	)

Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]

	Year ended December 31,
	2023			2022

Statutory income tax rate		21	%		21	%
Increase (decrease) in tax provision resulting from:
Equity compensation		0.4			(29.7	)
Global intangible low-taxed income		1.4			(73.1	)
China R&D deduction		(1.0	)		20.6
Income tax credits		(3.3	)		81.0
Foreign tax rate change		-			18.3
Foreign tax rates		1.7			11.5
States taxes		0.8			(3.4	)
Other		0.4			26.9
Effective income tax rate		21.4	%		73.1	%

Note 1 - Summary of Operations and Significant Accounting Policies

12 Months Ended

Dec. 31, 2023

Business Description and Accounting Policies [Text Block]

Note 1 - Summary of Operations and Significant Accounting Policies

a.	Description of Business

As used in this annual report, unless otherwise indicated, the terms the “Company”, “we”, “our” and “us” refer to Ultralife Corporation (“Ultralife”) and its wholly owned subsidiaries ABLE New Energy Co., Limited and its wholly owned subsidiary ABLE New Energy Co., Ltd (collectively “ABLE”); Ultralife UK LTD and its wholly owned subsidiary Accutronics Ltd (collectively “Accutronics”); Ultralife Batteries (UK) Ltd.; Southwest Electronic Energy Corporation and its wholly owned subsidiary, CLB, Inc. (collectively “SWE”); Ultralife Excell Holding Corp. (“UEHC”) and its wholly owned subsidiary Excell Battery Corporation USA (collectively “Excell USA”), Ultralife Canada Holding Corp (wholly owned by UEHC, “UCHC”) and its wholly owned subsidiary Excell Battery Canada ULC (“Excell Canada,” and collectively “Excell”); and its majority-owned joint venture Ultralife Batteries India Private Limited (“Ultralife India”).

We offer products and services ranging from power solutions to communications and electronics systems. Through our engineering and collaborative approach to problem solving, we serve government, defense and commercial customers across the globe. We design, manufacture, install and maintain power and communications systems including rechargeable and non-rechargeable batteries, charging systems, communications and electronics systems and accessories, and custom engineered systems. We sell our products worldwide through a variety of trade channels, including original equipment manufacturers (“OEMs”), industrial and defense supply distributors, and directly to U.S. and international defense departments.

b.	Principles of Consolidation

The consolidated financial statements are prepared in accordance with generally accepted accounting principles in the United States (“GAAP”) and include the accounts of Ultralife Corporation and its wholly owned subsidiaries ABLE, Accutronics, Ultralife Batteries (UK) Ltd., SWE, Excell, and its majority-owned joint venture Ultralife India. Intercompany accounts and transactions have been eliminated in consolidation.

c.	Management's Use of Judgment and Estimates

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at year end and the reported amounts of revenues and expenses during the reporting period. Key areas affected by estimates include: (a) carrying value of goodwill and intangible assets; (b) reserves for excess and obsolete inventory, deferred tax assets, warranties, and bad debts; (c) valuation of assets acquired and liabilities assumed in business combinations; (d) various expense accruals; and (e) stock-based compensation. Our actual results could differ from these estimates.

d.	Reclassifications

Certain items previously reported in specific financial statement captions are reclassified to conform to the current presentation. There were no material reclassifications for the years ended December 31, 2023 and 2022.

Cash

Our cash balances may at times exceed federally insured limits. We have not experienced any losses in these accounts and believe we are not exposed to any significant risk with respect to cash.

f.	Accounts Receivable and Allowance for Expected Credit Losses

We extend credit to our customers in the normal course of business. We perform ongoing credit evaluations and generally do not require collateral. Payment terms are generally thirty (30) to sixty (60) days. Trade accounts receivable are recorded at their invoiced amounts, net of allowance for expected credit losses. We evaluate the adequacy of our allowance for doubtful accounts quarterly. Accounts outstanding for longer than contractual payment terms are considered past due and are reviewed for collectability. We maintain reserves for potential credit losses based upon our historical experience, aging profile and general market conditions. Receivable balances are written off when collection is deemed unlikely.

g.	Inventories

Inventories are stated at the lower of cost or net realizable value with cost determined under the first‑in, first‑out (FIFO) method. We record provisions for excess, obsolete or slow-moving inventory based on changes in customer demand, technology developments or other economic factors.

h.	Property, Plant and Equipment

Property, plant and equipment is stated at cost. Depreciation is computed using the straight-line method over the estimated useful lives. Estimated useful lives are as follows (in years):

Betterments, renewals and extraordinary repairs that extend the life of the assets are capitalized. Other repairs and maintenance costs are expensed when incurred. When disposed, the cost and accumulated depreciation applicable to assets retired are removed from the accounts and the gain or loss on disposition is recognized in operating income.

i.	Long-Lived Assets, Goodwill and Intangibles

We assess our long-lived assets for impairment whenever events or circumstances indicate that their carrying amounts may not be recoverable. For property, plant and equipment and amortizable intangible assets, this is accomplished by comparing the expected undiscounted future cash flows of the assets with the respective carrying amount as of the date of assessment. If the expected undiscounted future cash flows exceed the respective carrying amount as of the date of assessment, no impairment is recognized. Should aggregate undiscounted future cash flows be less than the carrying value, a write-down would be required, measured as the difference between the carrying value and the fair value of the asset. Fair value is estimated as the present value of expected discounted future cash flows. The discount rate used in our evaluation is an industry-based weighted average cost of capital.

Under the acquisition method of accounting, the purchase price paid, or the total consideration transferred, to consummate the acquisition is allocated to the identified tangible and intangible assets acquired and liabilities assumed based on their respective estimated fair values as of the acquisition date with the residual amount recorded to goodwill. We do not amortize goodwill and intangible assets with indefinite lives, but instead evaluate these assets for impairment at least annually, or whenever events or circumstances indicate that impairment may exist. We amortize intangible assets that have definite lives so that the economic benefits of the intangible assets are being recognized over their estimated useful life.

The annual impairment test for goodwill consists of a comparison of the estimated fair value for each reporting unit to which goodwill is assigned to the carrying value of the respective reporting unit. The annual impairment test for other indefinite-lived intangible assets consists of a comparison of the estimated fair value of each asset to the carrying value of the respective asset. If the estimated fair value of a reporting unit or other indefinite-lived intangible asset exceeds its respective carrying value, the goodwill or indefinite-lived intangible asset is considered not impaired. If carrying value of a reporting unit or indefinite-lived intangible asset exceeds its estimated fair value, the excess carrying value of the respective goodwill or indefinite-lived intangible asset is recognized as an impairment loss.

j.	Translation of Foreign Currency

The financial statements of our foreign subsidiaries are translated from the functional currency into U.S. dollar equivalents, with translation adjustments recorded as the sole component of accumulated other comprehensive income (loss). Exchange gains and losses related to foreign currency transactions and balances denominated in currencies other than the functional currency are recognized in net income (loss).

k.	Revenue Recognition

Revenues are generated from the sale of products. Performance obligations are met and revenue is recognized upon transfer of control to the customer, which is generally upon shipment. When contract terms require transfer of control upon delivery at a customer’s location, revenue is recognized on the date of delivery. For products shipped under vendor managed inventory arrangements, revenue is recognized and billed when the product is consumed by the customer, at which point control has transferred and there are no further obligations by the Company. Revenue is measured as the amount of consideration we expect to receive in exchange for shipped product. Sales, value-added and other taxes billed and collected from customers are excluded from revenue. Customers, including distributors, do not have a general right of return.

Separately priced extended warranty contracts are offered on certain Communications Systems products for a duration of up to eight (8) years. Extended warranties are treated as separate performance obligations and recognized to revenue evenly over the term of the respective contract. Revenue not yet recognized on extended warranty contracts is recorded as deferred revenue on the consolidated balance sheet.

As of December 31, 2023, there was deferred revenue on extended warranty contracts of $1,407, comprised of $287 expected to be recognized as revenue within one (1) year and classified as accrued expenses and other current liabilities on our consolidated balance sheet, and $1,120 expected to be recognized as revenue over the remaining duration of the respective contracts and classified as other noncurrent liabilities on our consolidated balance sheet.

As of December 31, 2023 and 2022, the Company had no other unsatisfied performance obligations for contracts with an original expected duration of greater than one year. Pursuant to Topic 606, we have applied the practical expedient with respect to disclosure of the deferral and future expected timing of revenue recognition for transaction price allocated to remaining performance obligations.

l.	Warranty Reserves

m.	Shipping and Handling Costs

Costs incurred by us related to shipping and handling are included in cost of products sold. Amounts charged to customers pertaining to these costs are reflected as revenue.

n.	Sales Commissions

Sales commissions are expensed as incurred for contracts with an expected duration of one year or less. There were no sales commissions capitalized as of December 31, 2023 and 2022.

o.	Research and Development

Research and development expenditures are charged to operations as incurred. The majority of research and development expenses pertain to salaries and benefits, developmental supplies, depreciation and other contracted services. For the years ended December 31, 2023 and 2022, we expended $8,587 and $7,874, respectively, on research and development, including costs of $1,056 and $793, respectively, on customer sponsored research and development activities, which are included in cost of products sold.

p.	Environmental Costs

Environmental expenditures that relate to current operations are expensed. Remediation costs that relate to an existing condition caused by past operations are accrued when it is probable that these costs will be incurred and can be reasonably estimated.

q.	Income Taxes

We account for income taxes using the asset and liability method. Under this method, deferred tax assets and liabilities are determined based on differences between financial reporting and tax basis of assets and liabilities and are measured using the enacted tax rates and laws that are expected to be in effect when the differences are expected to reverse. Pursuant to ASC 740, a valuation allowance is recognized when the realizability of deferred tax assets is not more likely than not, based all available evidence, both positive and negative, weighted based on objective verifiability.

r.	Concentration Related to Customers and Suppliers

One of our customers, a large global defense primary contractor, comprised 15% and 17% of our total consolidated revenues for 2023 and 2022, respectively. Revenues for this customer represented 18% and 19% of our total Battery & Energy Products segment revenues for 2023 and 2022, respectively. There were no other customers that comprised greater than 10% of our total consolidated revenues during these years.

s.	Fair Value Measurements and Disclosures

Fair value is defined as the price that would be received for an asset or the exit price that would be paid to transfer a liability in the principal or most advantageous market in an orderly transaction between market participants on the measurement date. Fair value is estimated by applying the following hierarchy, which prioritizes the inputs used to measure fair value into three levels and bases the categorization within the hierarchy upon the lowest level of input that is available and significant to the fair value measurement:

Level 1:

Quoted prices in active markets for identical assets or liabilities.

Level 2:

Observable inputs, other than Level 1 prices, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or that we corroborate with observable market data for substantially the full term of the related assets or liabilities.

Level 3:

Unobservable inputs supported by little or no market activity that are significant to the fair value of the assets or liabilities.

The fair value of financial instruments approximated their carrying values at December 31, 2023 and 2022. The fair value of cash, accounts receivable, accounts payable, accrued liabilities, and the current portion of long-term debt approximates carrying value due to the short-term nature of these instruments. The carrying value of long-term debt approximates fair value, as the variable interest rates approximate current market rates.

t.	Earnings Per Share

Basic earnings per share (“EPS”) is computed by dividing net income (loss) attributable to Ultralife Corporation by the weighted average shares of common stock outstanding for the period. Diluted EPS reflects the assumed exercise and conversion of dilutive outstanding stock options and unvested restricted stock, if any, applying the treasury stock method.

For the year ended December 31, 2023, there were 111,247 outstanding stock options and 4,029 unvested restricted stock awards included in the calculation of diluted weighted average shares outstanding, as such securities were dilutive, resulting in 12,661 potential common shares included in the calculation of diluted EPS. There were 1,139,348 outstanding stock options for the year ended December 31, 2023 not included in EPS as the effect would be antidilutive.

For the comparable year ended December 31, 2022, there were no potential common shares included in the calculation of diluted weighted average shares outstanding and diluted EPS, as no outstanding securities were dilutive. There were 1,425,693 outstanding stock options and 2,500 unvested restricted stock awards not included in the calculation of diluted EPS for the year ended December 31, 2022, as the effect would be antidilutive.

u.	Stock-Based Compensation

We have various stock-based employee compensation plans that are described more fully in Note 5. The compensation cost relating to share-based payment transactions is measured at the grant date, based on the estimated fair value of the award, and is recognized as expense over the employee’s requisite service period (generally the vesting period of the equity award).

v.	Segment Reporting

We have two operating segments – Battery & Energy Products and Communications Systems. The basis for determining our operating segments is the manner in which financial information is used in monitoring our operations. Management operates and organizes itself according to business units that comprise unique products and services across geographic locations.

w.	Business Combinations

We allocate the purchase price of acquired businesses to the tangible and intangible assets acquired and the liabilities assumed based on their estimated fair values on the acquisition date. Any excess of the purchase price over the net fair value of the separately identifiable assets acquired and liabilities assumed is allocated to goodwill. Management determines the fair values of identifiable intangible assets acquired based on historical data, estimated discounted future cash flows, expected royalty rates for trademarks and trade names, as well as certain other information. The valuation of assets acquired and liabilities assumed requires a number of judgments and is subject to change as additional information about the fair value of assets and liabilities becomes available. Additional information, which existed as of the acquisition date but unknown to us at that time, may become known during the remainder of the measurement period. This measurement period may not exceed twelve months from the acquisition date. We will recognize any adjustments to provisional amounts that are identified during the measurement period in the reporting period in which the adjustments are determined. Additionally, in the same period in which adjustments are recognized, we will record the effect on earnings of changes in depreciation, amortization, or other income effects, if any, as a result of any change to the provisional amounts, calculated as if the accounting adjustment had been completed at the acquisition date. Acquisition costs are expensed as incurred. The results of operations and cash flows of acquired businesses are included in our consolidated financial statements from the date of acquisition.

Leases

At contract inception, the Company determines whether the arrangement is or contains a lease and determines the lease classification. The lease term is determined based on the non-cancellable term of the lease adjusted to the extent optional renewal terms and termination rights are reasonably certain. Lease expense for operating leases is recognized evenly over the lease term. Variable lease payments are recognized as period costs. The present value of remaining lease payments is recognized as a liability on the balance sheet with a corresponding right-of-use asset adjusted for prepaid or accrued lease payments. The Company uses its incremental borrowing rate for the discount rate, unless the interest rate implicit in the lease contract is readily determinable. The Company has adopted the practical expedients to not separate non-lease components from lease components and to not present short-term leases on the balance sheet. See Note 7 for further disclosure regarding lease accounting.

y.	Recent Accounting Pronouncements

Recently Adopted Accounting Guidance

In June 2016, the Financial Accounting Standards Board (“FASB”) issued ASU 2016-13, “Financial Instruments – Credit Losses (Topic 326) – Measurement of Credit Losses on Financial Instruments”, which requires entities to measure all expected credit losses for financial assets held at the reporting date based on historical experience, current conditions, and reasonable and supportable forecasts. This replaces the existing incurred loss model and is applicable to the measurement of credit losses on financial assets measured at amortized cost. This guidance was effective for the Company for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2022. The adoption of this new accounting standard did not have a material impact on our consolidated financial statements.

Recent Accounting Guidance Not Yet Adopted

In December 2023, the FASB issued ASU 2023-09 "Income Taxes (Topics 740): Improvements to Income Tax Disclosures" to expand the disclosure requirements for income taxes, specifically related to the rate reconciliation and income taxes paid. ASU 2023-09 is effective for our annual periods beginning January 1, 2025, with early adoption permitted. We are currently evaluating the potential effect that the updated standard will have on our financial statement disclosures.

Note 6 - Income Taxes (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Income Tax Expense (Benefit)	$ 1,951	$ (326)
Income Tax Expense (Benefit)	(1,951)	326
Operating Loss Carryforwards	1,300
Deferred Tax Assets, Valuation Allowance	2,441	2,416
Unrecognized Tax Benefits, Ending Balance	0
General Business Tax Credit Carryforward [Member]
Tax Credit Carryforward, Amount		$ 2,900
Domestic Tax Authority [Member] \| Internal Revenue Service (IRS) [Member]
Operating Loss Carryforwards	$ 27,200
Open Tax Year	2002 2005 2006 2007 2011 2012 2013 2014 2015
Foreign Tax Authority [Member]
Deferred Tax Assets, Valuation Allowance	$ 0
Open Tax Year	2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021
Foreign Tax Authority [Member] \| Her Majesty's Revenue and Customs (HMRC) [Member]
Operating Loss Carryforwards	$ 9,800
State and Local Jurisdiction [Member]
Open Tax Year	2002 2005 2006 2007 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021

Note 9 - Business Segment Information - Segment Activity (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Revenue	$ 158,644	$ 131,840
Segment contribution	9,475	129
Other expense, net	358	575
Income tax benefit	1,951	(326)
Non-controlling interest	(31)	(1)
Net loss attributable to Ultralife	7,197	(119)
Total assets	178,276	168,430
Total assets	178,276	168,430
Capital expenditures	2,552	1,679
Goodwill	37,571	37,428
Depreciation and amortization of intangible assets	3,911	4,459
Stock-based compensation	528	776
Battery & Energy Products Segment [Member]
Revenue	129,953	119,995
Segment contribution	30,775	26,154
Total assets	124,411	117,017
Total assets	124,411	117,017
Capital expenditures	2,064	1,371
Goodwill	26,078	25,935
Depreciation and amortization of intangible assets	3,336	3,761
Stock-based compensation	336	396
Communications Systems Segment [Member]
Revenue	28,691	11,845
Segment contribution	8,425	3,246
Total assets	28,873	29,424
Total assets	28,873	29,424
Capital expenditures	118	81
Goodwill	11,493	11,493
Depreciation and amortization of intangible assets	183	261
Stock-based compensation	74	82
Corporate Segment [Member]
Revenue	0	0
Segment contribution	(29,725)	(29,271)
Other expense, net	358	575
Income tax benefit	1,951	(326)
Non-controlling interest	(31)	(1)
Total assets	24,992	21,989
Total assets	24,992	21,989
Capital expenditures	370	227
Goodwill	0	0
Depreciation and amortization of intangible assets	392	437
Stock-based compensation	$ 118	$ 298

Note 8 - 401(k) Retirement Benefit Plan (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Defined Contribution Plan, Employer Matching Contribution, First 3%, Percent of Match	100.00%
Defined Contribution Plan, Maximum Employee Contribution Percentage, Subject to Employer Matching Contribution	3.00%
Defined Contribution Plan, Employer Matching Contribution, Next 2%, Percent of Match	50.00%
Defined Contribution Plan, Maximum Employee Contribution Percentage, Subject to Employer 50% Matching Contribution	2.00%
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay	4.00%
Defined Contribution Plan, Employer Discretionary Contribution Amount	$ 678	$ 600

Note 5 - Stock-based Compensation

12 Months Ended

Dec. 31, 2023

Shareholders' Equity and Share-Based Payments [Text Block]

Note 5 – Stock-Based Compensation

We recorded non-cash stock compensation expense in each period as follows:

	Year ended December 31,
	2023		2022
Stock options	$	522	$	761
Restricted stock		6		15
Total	$	528	$	776

We have various stock-based employee compensation plans, for which compensation cost is recognized in the financial statements. The cost is measured at the grant date, based on the estimated fair value of the award, and is recognized as an expense over the employee’s requisite service period (generally the vesting period of the equity award).

Our stockholders have approved various equity-based plans that permit the grant of stock options, restricted stock and other equity-based awards. In addition, our stockholders have approved the grant of stock options outside of these plans.

In June 2014, our stockholders approved the 2014 Long-Term Incentive Plan (“2014 LTIP”) as the successor plan to the 2004 Long-Term Incentive Plan (“2004 LTIP”) that expired on June 10, 2014. Under the 2014 LTIP, a total of 1,750,000 shares of common stock were made available for grant of awards. In July 2021, our stockholders approved an amendment to the 2014 LTIP to increase the total number shares of our common stock authorized to be issued pursuant to the 2014 LTIP to 2,750,000. Of the total number of shares of common stock available for awards under the 2014 LTIP, no more than 800,000 shares of common stock may be used for awards other than stock options and stock appreciation rights. Grants under the 2014 LTIP may be awarded through June 2, 2024.

Stock options granted under the 2014 LTIP are either Incentive Stock Options (“ISOs”) or Non-Qualified Stock Options (“NQSOs”). Key employees are eligible to receive ISOs and NQSOs; however, directors and consultants are eligible to receive only NQSOs. Stock options vest in equal installments on the first, second and third anniversaries of the grant date and expire on the seventh anniversary of the grant date. As of December 31, 2023, there were 1,250,595 stock options outstanding under the 2014 LTIP. There were no stock options outstanding under the 2004 LTIP.

As of December 31, 2023, there was $844 of total unrecognized compensation costs related to outstanding stock options, which we expect to recognize over a weighted average period of 1.5 years.

We use the Black-Scholes option-pricing model to estimate fair value of stock-based awards. The following weighted average assumptions were used to value options granted during the years ended December 31, 2023 and 2022:

	Year ended December 31,
	2023			2022
Risk-free interest rate		4.1	%		4.2	%
Volatility factor		57	%		50	%
Weighted average expected life (years)		4.9			4.8
Forfeiture rate		10.0	%		10.0	%
Dividends		0.0	%		0.0	%

We used a Monte Carlo simulation option-pricing model to estimate the fair value of market performance stock-based awards, of which there were no new awards for the years ended December 31, 2023 and 2022.

We calculate expected volatility for stock options by taking an average of historical volatility over the expected term. The computation of expected term was determined based on historical experience of similar awards, giving consideration to the contractual terms of the stock-based awards and vesting schedules. The interest rate for periods within the contractual life of the award is based on the U.S. Treasury yield in effect at the time of grant. Forfeiture rates are calculated by dividing unvested shares forfeited by beginning shares outstanding. The pre-vesting forfeiture rate is calculated yearly and is determined based on historical experience.

The following tables summarize data for the stock options issued by us:

Year ended December 31, 2023
	Number of shares			Weighted average exercise price per share		Weighted average remaining contractual term		Aggregate intrinsic value
Shares under option – January 1		1,425,693		$	6.72
Options granted		231,650			6.69
Options exercised		(254,393	)		5.83
Options forfeited or expired		(152,355	)		5.06
Shares under option – December 31		1,250,595		$	7.10		3.97	$	515
Vested and expected to vest - December 31		1,151,228		$	7.17		3.79	$	452

Options exercisable – December 31		789,209		$	7.56		2.69	$	241

Year ended December 31, 2022
	Number of shares			Weighted average exercise price per share
Shares under option – January 1		1,306,824		$	6.87
Options granted		289,950			5.42
Options exercised		(59,500	)		3.82
Options forfeited or expired		(111,581	)		6.56
Shares under option – December 31		1,425,693		$	6.72

Options exercisable – December 31		881,804		$	7.13

The following table represents additional information about stock options outstanding at December 31, 2023:

			Option outstanding						Options exercisable
Range of exercise prices			Number of outstanding options		Weighted- average remaining contractual life		Weighted- average exercise price		Number of options exercisable		Weighted- average exercise price
$4.07	-	$6.36		338,364		4.79	$	5.42		156,099	$	5.54
$6.51	-	$6.84		353,733		5.54		6.71		134,583		6.51
$6.97	-	$8.25		334,165		2.89		7.64		290,355		7.74
$8.45	-	$9.96		224,333		1.88		9.44		208,172		9.51

$4.07	-	$9.96		1,250,595		3.97	$	7.10		789,209	$	7.56

The weighted average fair value of options granted during the years ended December 31, 2023 and 2022 was $3.48 and $2.55, respectively. The total intrinsic value of options (which is the amount by which the stock price exceeded the exercise price of the options on the date of exercise) exercised during the years ended December 31, 2023 and 2022 was $556 and $88, respectively.

Cash received from stock option exercises under our stock-based compensation plans for the years ended December 31, 2023 and 2022 was $1,248 and $116, respectively.

Restricted shares vest in equal annual installments over three years. In November 2023, we granted 4,029 shares of restricted stock awards. As of December 31, 2023, there was $27 of total unrecognized compensation costs related to outstanding restricted shares.

There were 632,593 shares of common stock available for future issuance under equity compensation plans as of December 31, 2023.

Note 3 - Supplemental Balance Sheet Information - Components of Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Property, plant and equipment, gross	$ 87,601	$ 92,660
Less – Accumulated depreciation	(66,484)	(70,944)
Total	21,117	21,716
Land [Member]
Property, plant and equipment, gross	1,273	1,273
Building and Building Improvements [Member]
Property, plant and equipment, gross	15,998	15,572
Machinery and Equipment [Member]
Property, plant and equipment, gross	57,584	63,981
Furniture and Fixtures [Member]
Property, plant and equipment, gross	2,845	2,845
Computer Equipment [Member]
Property, plant and equipment, gross	7,868	7,744
Construction in Progress [Member]
Property, plant and equipment, gross	$ 2,033	$ 1,245

Note 3 - Supplemental Balance Sheet Information (Details Textual) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents	$ 10,278	$ 5,713	$ 8,413
Restricted Cash and Cash Equivalents	82	79
Depreciation	$ 3,022	3,177
Number of Reporting Units	2
Goodwill, Impairment Loss	$ 0
Finite-Lived Intangible Asset, Expected Amortization, Year One	912
Finite-Lived Intangible Asset, Expected Amortization, Year Two	912
Finite-Lived Intangible Asset, Expected Amortization, Year Three	775
Finite-Lived Intangible Asset, Expected Amortization, Year Four	775
Finite-Lived Intangible Asset, Expected Amortization, Year Five	774
NETHERLANDS
Restricted Cash and Cash Equivalents	$ 82	$ 79

Note 6 - Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Net operating loss carryforwards	$ 8,515	$ 11,460
Research and development	3,536	2,812
Tax credit carryforwards	2,898	2,600
Accrued expenses, reserves and other	2,909	2,419
Intangible assets	1,596	1,521
Total deferred tax assets	19,454	20,812
Valuation allowance for deferred tax assets	(2,441)	(2,416)
Net deferred tax assets	17,013	18,396
Intangible assets	(8,095)	(8,176)
Accrued expenses, reserves and other	(65)	(68)
Total deferred tax liabilities	(8,160)	(8,244)
Net deferred tax assets	$ 8,853	$ 10,152

Note 3 - Supplemental Balance Sheet Information - Components of Inventory (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Raw materials	$ 29,098	$ 29,200
Work in process	3,187	2,757
Finished products	9,930	9,235
Total	$ 42,215	$ 41,192

Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2023

Accounting Policies [Abstract]

Consolidation, Policy [Policy Text Block]

b.	Principles of Consolidation

Use of Estimates, Policy [Policy Text Block]

c.	Management's Use of Judgment and Estimates

Reclassification, Comparability Adjustment [Policy Text Block]

d.	Reclassifications

Cash and Cash Equivalents, Policy [Policy Text Block]

Cash

Our cash balances may at times exceed federally insured limits. We have not experienced any losses in these accounts and believe we are not exposed to any significant risk with respect to cash.

Receivable [Policy Text Block]

f.	Accounts Receivable and Allowance for Expected Credit Losses

Inventory, Policy [Policy Text Block]

g.	Inventories

Property, Plant and Equipment, Policy [Policy Text Block]

h.	Property, Plant and Equipment

Property, plant and equipment is stated at cost. Depreciation is computed using the straight-line method over the estimated useful lives. Estimated useful lives are as follows (in years):

Goodwill and Intangible Assets, Policy [Policy Text Block]

i.	Long-Lived Assets, Goodwill and Intangibles

Foreign Currency Transactions and Translations Policy [Policy Text Block]

j.	Translation of Foreign Currency

Revenue [Policy Text Block]

k.	Revenue Recognition

Guarantees, Indemnifications and Warranties Policies [Policy Text Block]

l.	Warranty Reserves

Shipping and Handling Costs [Policy Text Block]

m.	Shipping and Handling Costs

Costs incurred by us related to shipping and handling are included in cost of products sold. Amounts charged to customers pertaining to these costs are reflected as revenue.

Sales Commissions [Policy Text Block]

n.	Sales Commissions

Sales commissions are expensed as incurred for contracts with an expected duration of one year or less. There were no sales commissions capitalized as of December 31, 2023 and 2022.

Research and Development Expense, Policy [Policy Text Block]

o.	Research and Development

Environmental Cost, Expense Policy [Policy Text Block]

p.	Environmental Costs

Income Tax, Policy [Policy Text Block]

q.	Income Taxes

Concentration Risk, Credit Risk, Policy [Policy Text Block]

r.	Concentration Related to Customers and Suppliers

Fair Value Measurement, Policy [Policy Text Block]

s.	Fair Value Measurements and Disclosures

Level 1:

Quoted prices in active markets for identical assets or liabilities.

Level 2:

Level 3:

Unobservable inputs supported by little or no market activity that are significant to the fair value of the assets or liabilities.

Earnings Per Share, Policy [Policy Text Block]

t.	Earnings Per Share

Share-Based Payment Arrangement [Policy Text Block]

u.	Stock-Based Compensation

Business Combinations Policy [Policy Text Block]

w.	Business Combinations

Lessee, Leases [Policy Text Block]

Leases

New Accounting Pronouncements, Policy [Policy Text Block]

y.	Recent Accounting Pronouncements

Recently Adopted Accounting Guidance

Recent Accounting Guidance Not Yet Adopted

Consolidated Statements of Changes in Shareholders' Equity - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-in Capital [Member]	AOCI Attributable to Parent [Member]	Retained Earnings [Member]	Treasury Stock, Common [Member]	Noncontrolling Interest [Member]	Total
Balance (in shares) at Dec. 31, 2021	20,522,427						16,135,358
Balance at Dec. 31, 2021	$ 2,052	$ 186,518	$ (1,653)	$ (47,832)	$ (21,469)	$ 127	$ 117,743
Net loss				(119)		(1)	$ (120)
Stock option exercises (in shares)	39,119						59,500
Stock option exercises	$ 4	112			(7)		$ 109
Stock-based compensation -stock options		761					761
Stock-based compensation -restricted stock		15					15
Vesting of restricted stock (in shares)	9,164
Vesting of restricted stock	$ 1	(1)			(8)		(8)
Foreign currency translation adjustments			(2,097)				$ (2,097)
Balance (in shares) at Dec. 31, 2022	20,570,710						16,347,493
Balance at Dec. 31, 2022	$ 2,057	187,405	(3,750)	(47,951)	(21,484)	126	$ 116,403
Net loss				7,197		(31)	$ 7,166
Stock option exercises (in shares)	210,397						254,393
Stock option exercises	$ 21	1,227			0		$ 1,248
Stock-based compensation -stock options		522					522
Stock-based compensation -restricted stock		6					6
Vesting of restricted stock (in shares)	2,500
Vesting of restricted stock	$ 0	0			(8)		(8)
Foreign currency translation adjustments			90				90
Balance (in shares) at Dec. 31, 2023	20,783,607
Balance at Dec. 31, 2023	$ 2,078	$ 189,160	$ (3,660)	$ (40,754)	$ (21,492)	$ 95	$ 125,427

Note 9 - Business Segment Information - Revenue by Business Segment Sector (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Revenues	$ 158,644	$ 131,840
UNITED STATES
Revenues	$ 81,396	$ 67,914
Revenue, percentage	51.00%	52.00%
Non-US [Member]
Revenues	$ 77,248	$ 63,926
Revenue, percentage	49.00%	48.00%
Commercial [Member]
Revenues	$ 100,842	$ 93,045
Revenue, percentage	64.00%	71.00%
Government & Defense [Member]
Revenues	$ 57,802	$ 38,795
Revenue, percentage	36.00%	29.00%
Battery & Energy Products Segment [Member]
Revenues	$ 129,953	$ 119,995
Battery & Energy Products Segment [Member] \| UNITED STATES
Revenues	64,120	58,820
Battery & Energy Products Segment [Member] \| Non-US [Member]
Revenues	65,833	61,175
Battery & Energy Products Segment [Member] \| Commercial [Member]
Revenues	100,842	93,045
Battery & Energy Products Segment [Member] \| Government & Defense [Member]
Revenues	29,111	26,950
Communications Systems Segment [Member]
Revenues	28,691	11,845
Communications Systems Segment [Member] \| UNITED STATES
Revenues	17,276	9,094
Communications Systems Segment [Member] \| Non-US [Member]
Revenues	11,415	2,751
Communications Systems Segment [Member] \| Commercial [Member]
Revenues	0	0
Communications Systems Segment [Member] \| Government & Defense [Member]
Revenues	$ 28,691	$ 11,845

Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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Note 5 - Stock-based Compensation - Stock Option Assumptions (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Risk-free interest rate	4.10%	4.20%
Volatility factor	57.00%	50.00%
Weighted average expected life (years) (Year)	4 years 10 months 24 days	4 years 9 months 18 days
Forfeiture rate	10.00%	10.00%
Dividends	0.00%	0.00%

Note 2 - Debt - Future Minimum Principal Repayment Obligations (Details) $ in Thousands	Dec. 31, 2023 USD ($)
2024	$ 2,000
2025	21,580
2026	2,000
2027	167
Thereafter	0
Total	$ 25,747

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

+ References + Details

Note 1 - Summary of Operations and Significant Accounting Policies - Property, Plant and Equipment Estimated Useful Life (Details)	Dec. 31, 2023
Building [Member] \| Minimum [Member]
Buildings (Year)	10 years
Building [Member] \| Maximum [Member]
Buildings (Year)	40 years
Machinery and Equipment [Member] \| Minimum [Member]
Buildings (Year)	5 years
Machinery and Equipment [Member] \| Maximum [Member]
Buildings (Year)	10 years
Furniture and Fixtures [Member] \| Minimum [Member]
Buildings (Year)	3 years
Furniture and Fixtures [Member] \| Maximum [Member]
Buildings (Year)	10 years
Computer Equipment [Member] \| Minimum [Member]
Buildings (Year)	2 years
Computer Equipment [Member] \| Maximum [Member]
Buildings (Year)	5 years

Note 2 - Debt

12 Months Ended

Dec. 31, 2023

Debt Disclosure [Text Block]

Note 2 – Debt

Credit Facilities

On December 13, 2021, Ultralife, Southwest Electronic Energy Corporation, a Texas corporation and wholly owned subsidiary of Ultralife (“SWE”), CLB, INC., a Texas corporation and wholly owned subsidiary of SWE (“CLB”), Ultralife Excell Holding Corp., a Delaware corporation and wholly owned subsidiary of Ultralife (“UEHC”), Ultralife Canada Holding Corp., a Delaware corporation and wholly owned subsidiary of UEHC (“UCHC”), and Excell Battery Corporation USA, a Texas corporation and wholly owned subsidiary of UEHC (“Excell USA”), as borrowers, entered into the Second Amendment Agreement with KeyBank National Association (“KeyBank” or the “Bank”), as lender and administrative agent, to amend the Credit and Security Agreement dated May 31, 2017 as amended by the First Amendment Agreement by and among Ultralife, SWE, CLB and KeyBank dated May 1, 2019 (the “Credit Agreement”). On November 28, 2022, Ultralife, SWE, CLB, UEHC, UCHC, Excell USA, and Excell Battery Canada ULC, a British Columbia unlimited liability corporation and wholly owned subsidiary of UCHC (“Excell Canada”), entered into that certain Third Amendment Agreement with KeyBank, to further amend the Credit Agreement to, among other things, facilitate the joinder of Excell Canada as a guarantor under the Credit Agreement and to replace the LIBOR benchmark thereunder with SOFR (the “Third Amendment Agreement”, and together with the Second Amendment Agreement and the Credit Agreement, the “Amended Credit Agreement”).

The Amended Credit Agreement, among other things, provides for a 5-year, $10,000 senior secured term loan (the “Term Loan Facility”) and extends the term of the $30,000 senior secured revolving credit facility (the “Revolving Credit Facility”, and together with the Term Loan Facility, the “Amended Credit Facilities”) through May 30, 2025. Up to six months prior to May 30, 2025, the Revolving Credit Facility may be increased to $50,000 with the Bank’s concurrence.

As of December 31, 2023, the Company had $6,167 outstanding principal on the Term Loan Facility, $2,000 of which is included in current portion of long-term debt on the balance sheet, and $19,580 outstanding on the Revolving Credit Facility. As of December 31, 2023, total unamortized debt issuance costs of $123, including placement, renewal and legal fees associated with the Amended Credit Agreement, are classified as a reduction of long-term debt on the balance sheet. Debt issuance costs are amortized to interest expense over the term of the Amended Credit Facilities.

The remaining availability under the Revolving Credit Facility is subject to certain borrowing base limits based on trade receivables and inventories.

The Company is required to repay the borrowings under the Term Loan Facility in equal consecutive monthly payments commencing on February 1, 2022, in arrears, together with applicable interest. All unpaid principal and accrued and unpaid interest with respect to the Term Loan Facility is due and payable in full on January 1, 2027. All unpaid principal and accrued and unpaid interest with respect to the Revolving Credit Facility is due and payable in full on May 30, 2025. The Company may voluntarily prepay principal amounts outstanding at any time subject to certain restrictions.

In addition to the customary affirmative and negative covenants, the Company must maintain a consolidated senior leverage ratio, as defined in the Amended Credit Agreement, of equal to or less than 3.5 to 1.0 for the fiscal quarters ending December 31, 2022 and March 31, 2023, and equal to or less than 3.0 to 1.0 for the fiscal quarters ending June 30, 2023 and thereafter. The Company was in full compliance with its covenants under the Amended Credit Agreement as of December 31, 2023.

Borrowings under the Amended Credit Facilities are secured by substantially all the assets of the Company and its subsidiaries.

Upon the effectiveness of the Third Amendment Agreement, interest accrues on outstanding indebtedness under the Amended Credit Facilities at the Daily Simple SOFR Rate, plus an index spread adjustment of 0.10%, plus the applicable margin. The applicable margin ranges from 185 to 215 basis points and is determined based on the Company’s senior leverage ratio.

The Company must pay a fee of 0.15% to 0.25% based on the average daily unused availability under the Revolving Credit Facility.

Payments must be made by the Company to the extent borrowings exceed the maximum amount then permitted to be drawn on the Amended Credit Facilities and from the proceeds of certain transactions. Upon the occurrence of an event of default, the outstanding obligations may be accelerated, and the Bank will have other customary remedies including resort to the security interest the Company provided to the Bank.

Future minimum principal repayment obligations on our Amended Credit Facilities as of December 31, 2023 are as follows:

2024	$	2,000
2025		21,580
2026		2,000
2027		167
Thereafter		0
Total	$	25,747

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Note 2 - Debt (Details Textual) - Amended Credit Agreement [Member] $ in Thousands	Dec. 13, 2021 USD ($)	Dec. 31, 2023 USD ($)	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022
Debt Issuance Costs, Gross		$ 123
Term Loan Facility [Member] \| Long-term Debt, Current Maturities [Member]
Secured Debt, Total		2,000
Revolving Credit Facility [Member]
Secured Debt, Total		6,167
Long-Term Line of Credit, Total		$ 19,580
Maximum Consolidated Senior Leverage Ratio			3	3.5	3.5
Revolving Credit Facility [Member] \| Minimum [Member]
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.15%
Revolving Credit Facility [Member] \| Maximum [Member]
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.25%
Revolving Credit Facility [Member] \| Secured Overnight Financing Rate (SOFR) [Member]
Debt Instrument, Basis Spread on Variable Rate	0.10%
Revolving Credit Facility [Member] \| Secured Overnight Financing Rate (SOFR) [Member] \| Minimum [Member]
Debt Instrument, Basis Spread on Variable Rate	1.85%
Revolving Credit Facility [Member] \| Secured Overnight Financing Rate (SOFR) [Member] \| Maximum [Member]
Debt Instrument, Basis Spread on Variable Rate	2.15%
KeyBank [Member] \| Term Loan Facility [Member]
Debt Instrument, Term	5 years
Debt Instrument, Face Amount	$ 10,000
KeyBank [Member] \| Revolving Credit Facility [Member]
Line of Credit Facility, Maximum Borrowing Capacity	30,000
Line Of Credit Facility Maximum Borrowing Capacity Contingent On Bank Approval	$ 50,000

Note 4 - Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2023

Schedule of Product Warranty Liability [Table Text Block]

	2023			2022
Accrued warranty obligations – beginning	$	323		$	133
Accruals for warranties issued		458			287
Settlements made		(234	)		(97	)
Accrued warranty obligations - ending	$	547		$	323

Note 3 - Supplemental Balance Sheet Information (Tables)

12 Months Ended

Dec. 31, 2023

Cash, Cash Equivalents and Investments [Table Text Block]

	December 31,
	2023		2022
Cash	$	10,196	$	5,634
Restricted cash		82		79
Total	$	10,278	$	5,713

Schedule of Inventory, Current [Table Text Block]

	December 31,
	2023		2022
Raw materials	$	29,098	$	29,200
Work in process		3,187		2,757
Finished products		9,930		9,235
Total	$	42,215	$	41,192

Property, Plant and Equipment [Table Text Block]

	December 31,
	2023			2022
Land	$	1,273		$	1,273
Buildings and leasehold improvements		15,998			15,572
Machinery and equipment		57,584			63,981
Furniture and fixtures		2,845			2,845
Computer hardware and software		7,868			7,744
Construction in progress		2,033			1,245
		87,601			92,660
Less: Accumulated depreciation		(66,484	)		(70,944	)
Total	$	21,117		$	21,716

Schedule of Goodwill [Table Text Block]

	Battery & Energy Products		Communications Systems		Total
Balance – January 1, 2023	$	25,935	$	11,493	$	37,428
Effect of foreign currency translation		143		-		143
Balance – December 31, 2023	$	26,078	$	11,493	$	37,571

Schedule of Finite-Lived Intangible Assets [Table Text Block]

	December 31, 2023
	Cost		Accumulated amortization		Net
Customer relationships	$	13,092	$	6,656	$	6,436
Patents and technology		5,606		5,322		284
Trade names		4,647		647		4,000
Trademarks		3,402		-		3,402
Other		1,500		515		985
Total other intangible assets	$	28,247	$	13,140	$	15,107

	December 31, 2022
	Cost		Accumulated amortization		Net
Customer relationships	$	12,970	$	5,992	$	6,978
Patents and technology		5,557		5,171		386
Trade names		4,629		522		4,107
Trademarks		3,404		-		3,404
Other		1,500		454		1,046
Total other intangible assets	$	28,060	$	12,139	$	15,921

Finite-Lived Intangible Assets Amortization Expense [Table Text Block]

	Year ended December 31,
	2023		2022
Research and development expense	$	97	$	97
Selling, general and administrative expense		792		1,185
Total	$	889	$	1,282

Tabular disclosure of goodwill by reportable segment and in total which includes a rollforward schedule.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 350
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 12: http://www.xbrl.org/2009/role/commonPracticeRef
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Document And Entity Information - USD ($)	12 Months Ended
Document And Entity Information - USD ($)	Dec. 31, 2023	Mar. 18, 2024	Jun. 30, 2023
Document Information [Line Items]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2023
Document Transition Report	false
Entity File Number	0-20852
Entity Registrant Name	ULTRALIFE CORPORATION
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	16-1387013
Entity Address, Address Line One	2000 Technology Parkway
Entity Address, City or Town	Newark
Entity Address, State or Province	NY
Entity Address, Postal Zip Code	14513
City Area Code	315
Local Phone Number	332-7100
Title of 12(b) Security	Common Stock, $0.10 par value per share
Trading Symbol	ULBI
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	false
Document Financial Statement Error Correction [Flag]	false
Entity Shell Company	false
Entity Public Float			$ 46,718,255
Entity Common Stock, Shares Outstanding (in shares)		16,446,832
Auditor Name	Freed Maxick CPAs, P.C.
Auditor Location	Rochester, New York
Auditor Firm ID	317
Entity Central Index Key	0000875657
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	FY
Amendment Flag	false

Note 4 - Commitments and Contingencies - Changes in Produce Warranty Liability (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Accrued warranty obligations – beginning	$ 323	$ 133
Accruals for warranties issued	458	287
Settlements made	(234)	(97)
Accrued warranty obligations - ending	$ 547	$ 323

Consolidated Balance Sheets (Parentheticals) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Trade accounts receivable, allowance for doubtful accounts	$ 300		$ 303
Preferred stock, par value (in dollars per share)		$ 0.1	$ 0.1
Preferred Stock, Shares Authorized (in shares)		1,000,000	1,000,000
Preferred Stock, Shares Issued (in shares)		0	0
Common stock, par value (in dollars per share)		$ 0.1	$ 0.1
Common Stock, Shares Authorized (in shares)		40,000,000	40,000,000
Common stock, shares issued (in shares)		20,783,607	20,570,710
Common stock, shares outstanding (in shares)		16,347,493	16,135,358
Treasury Stock, Common, Shares (in shares)		4,436,114	4,435,352

Note 5 - Share-based Compensation - Options Range of Exercise Prices (Details) - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Lower range limit (in dollars per share)	$ 4.07
Upper range limit (in dollars per share)	$ 9.96
Options outstanding, number of outstanding options (in shares)	1,250,595
Options outstanding, weighted-average remaining contractual life (Year)	3 years 11 months 19 days
Options outstanding, weighted-average exercise price (in dollars per share)	$ 7.1
Options exercisable, number of options exercisable (in shares)	789,209
Options exercisable – weighted average exercise price (in dollars per share)	$ 7.56	$ 7.13
Range One [Member]
Lower range limit (in dollars per share)	4.07
Upper range limit (in dollars per share)	$ 6.36
Options outstanding, number of outstanding options (in shares)	338,364
Options outstanding, weighted-average remaining contractual life (Year)	4 years 9 months 14 days
Options outstanding, weighted-average exercise price (in dollars per share)	$ 5.42
Options exercisable, number of options exercisable (in shares)	156,099
Options exercisable – weighted average exercise price (in dollars per share)	$ 5.54
Range Two [Member]
Lower range limit (in dollars per share)	6.51
Upper range limit (in dollars per share)	$ 6.84
Options outstanding, number of outstanding options (in shares)	353,733
Options outstanding, weighted-average remaining contractual life (Year)	5 years 6 months 14 days
Options outstanding, weighted-average exercise price (in dollars per share)	$ 6.71
Options exercisable, number of options exercisable (in shares)	134,583
Options exercisable – weighted average exercise price (in dollars per share)	$ 6.51
Range Three [Member]
Lower range limit (in dollars per share)	6.97
Upper range limit (in dollars per share)	$ 8.25
Options outstanding, number of outstanding options (in shares)	334,165
Options outstanding, weighted-average remaining contractual life (Year)	2 years 10 months 20 days
Options outstanding, weighted-average exercise price (in dollars per share)	$ 7.64
Options exercisable, number of options exercisable (in shares)	290,355
Options exercisable – weighted average exercise price (in dollars per share)	$ 7.74
Range Four [Member]
Lower range limit (in dollars per share)	8.45
Upper range limit (in dollars per share)	$ 9.96
Options outstanding, number of outstanding options (in shares)	224,333
Options outstanding, weighted-average remaining contractual life (Year)	1 year 10 months 17 days
Options outstanding, weighted-average exercise price (in dollars per share)	$ 9.44
Options exercisable, number of options exercisable (in shares)	208,172
Options exercisable – weighted average exercise price (in dollars per share)	$ 9.51

Consolidated Statements of Loss and Comprehensive Loss - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Revenues	$ 158,644	$ 131,840
Cost of products sold	119,444	102,440
Gross profit	39,200	29,400
Operating expenses:
Research and development	7,531	7,081
Selling, general and administrative	22,194	22,190
Total operating expenses	29,725	29,271
Operating income	9,475	129
Other expense (income):
Interest and financing expense	2,016	951
Miscellaneous income	(1,658)	(376)
Total other expense, net	358	575
Loss before income taxes	9,117	(446)
Income tax (benefit) provision	1,951	(326)
Net loss	7,166	(120)
Net (loss) income attributable to non-controlling interest	(31)	(1)
Loss attributable to Ultralife Corporation	7,197	(119)
Other comprehensive (loss) income:
Foreign currency translation adjustments	90	(2,097)
Comprehensive loss attributable to Ultralife Corporation	$ 7,287	$ (2,216)
Net loss per share attributable to Ultralife Corporation common shareholders – Basic (in dollars per share)	$ 0.03	$ 0.05
Net loss per share attributable to Ultralife Corporation common shareholders – Diluted (in dollars per share)	$ 0.03	$ 0.05
Weighted average shares outstanding – Basic (in shares)	16,214	16,125
Weighted average shares outstanding – Diluted (in shares)	16,226	16,125

Note 6 - Income Taxes - Effective Rate Reconciliation (Details)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Statutory income tax rate	21.00%	21.00%
Equity compensation	0.40%	29.70%
Equity compensation	(0.40%)	(29.70%)
Global intangible low-taxed income	1.40%	73.10%
Global intangible low-taxed income	(1.40%)	(73.10%)
China R&D deduction	(1.00%)	(20.60%)
China R&D deduction	1.00%	20.60%
Income tax credits	(3.30%)	(81.00%)
Income tax credits	3.30%	81.00%
Foreign tax rate change	0.00%	18.30%
Foreign tax rates	1.70%	11.50%
States taxes	0.80%	3.40%
States taxes	(0.80%)	(3.40%)
Other	0.40%	26.90%
Effective income tax rate	21.40%	73.10%

Note 6 - Income Taxes

12 Months Ended

Dec. 31, 2023

Income Tax Disclosure [Text Block]

Note 6 - Income Taxes

For the years ended December 31, 2023 and 2022, we recognized an income tax provision (benefit) of $1,951 and ($326), respectively.

	Year ended December 31,
	2023			2022
Current:
State	$	27		$	19
Foreign		623			617
		650			636
Deferred:
Federal		1,466			(661	)
Foreign		(165	)		(301	)
		1,301			(962	)
Total income tax (benefit) provision	$	1,951		$	(326	)

Deferred income taxes reflect the net tax effect of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amount used for income tax purposes. Significant components of our deferred tax assets and liabilities are as follows:

	December 31,
	2023			2022
Deferred tax assets:
Net operating loss carryforwards	$	8,515		$	11,460
Research and development		3,536			2,812
Tax credit carryforwards		2,898			2,600
Accrued expenses, reserves and other		2,909			2,419
Intangible assets		1,596			1,521
Total deferred tax assets		19,454			20,812
Valuation allowance for deferred tax assets		(2,441	)		(2,416	)
Net deferred tax assets		17,013			18,396

Deferred tax liabilities:
Intangible assets		(8,095	)		(8,176	)
Accrued expenses, reserves and other		(65	)		(68	)
Total deferred tax liabilities		(8,160	)		(8,244	)

Net deferred tax assets	$	8,853		$	10,152

Net deferred tax assets (liabilities) are comprised of the following balance sheet amounts:

	December 31,
	2023			2022

Deferred tax assets, net	$	10,567		$	12,069
Deferred tax liabilities		(1,714	)		(1,917	)
	$	8,853		$	10,152

For financial reporting purposes, net income (loss) from continuing operations before income taxes is as follows:

	Year ended December 31,
	2023		2022
United States	$	7,294	$	(2,771	)
Foreign		1,823		2,325
	$	9,117	$	(446	)

The provision for income taxes differs from the amount of income tax determined by applying the applicable U.S. statutory federal income tax rate to income from continuing operations before income taxes as follows:

	Year ended December 31,
	2023			2022

Statutory income tax rate		21	%		21	%
Increase (decrease) in tax provision resulting from:
Equity compensation		0.4			(29.7	)
Global intangible low-taxed income		1.4			(73.1	)
China R&D deduction		(1.0	)		20.6
Income tax credits		(3.3	)		81.0
Foreign tax rate change		-			18.3
Foreign tax rates		1.7			11.5
States taxes		0.8			(3.4	)
Other		0.4			26.9
Effective income tax rate		21.4	%		73.1	%

As of December 31, 2023, it was concluded that it is more likely than not that our U.S. deferred tax assets will be fully realized on the basis of management’s assessment. In evaluating the realizability of our U.S. deferred tax assets, management considered all available evidence, both positive and negative, weighted based on objective verifiability. Our assessment also considered our ability to fully utilize before expiration our domestic net operating loss carryforwards, which expire 2031 thru 2035, and our general business tax credit carryforwards, which expire 2028 thru 2043. As of December 31, 2023, our domestic net operating loss carryforwards and general business tax credits were $27,200 and $2,900, respectively.

As of December 31, 2023, for certain past operations in the U.K., we continue to report a valuation allowance for net operating loss carryforwards of approximately $9,800, nearly all of which can be carried forward indefinitely. Management has concluded that utilization of the U.K. net operating losses may be limited due to the change in the past U.K. operation, and that they cannot currently be used to reduce taxable income of our other U.K. subsidiary, Accutronics Ltd. There are no other deferred tax assets related to the past U.K. operations.

As of December 31, 2023, we have not recognized a valuation allowance against our other foreign deferred tax assets, including net operating loss carryforwards of $1,300 which expire 2028 thru 2033, as we believe that it is more likely than not that they will be fully realized.

There were no unrecognized tax benefits related to uncertain tax positions at December 31, 2023 and 2022.

As of December 31, 2023, the Company maintains its assertion that all foreign earnings will be indefinitely reinvested in those operations, other than earnings generated in the U.K.

As a result of our operations, we file income tax returns in various jurisdictions including U.S. federal, U.S. state and foreign jurisdictions. We are routinely subject to examination by taxing authorities in these various jurisdictions. Our U.S. tax matters for 2020 thru 2022 remain subject to IRS examination. Our U.S. tax matters for 2001-2002, 2005-2007, 2009, and 2011-2015 also remain subject to IRS examination due to the remaining availability of net operating loss carryforwards generated in those years. Our U.S. tax matters for 2013 thru 2022 remain subject to examination by various state and local tax jurisdictions. Our tax matters for the years 2013 thru 2022 remain subject to examination by the respective foreign tax jurisdiction authorities.

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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Material Terms of Trading Arrangement [Text Block]

Note 7 - Operating Leases - Lease Cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Operating lease cost	$ 1,016	$ 894
Variable lease cost	114	95
Total lease cost	$ 1,130	$ 989

Insider Trading Arrangements

12 Months Ended

Dec. 31, 2023

Insider Trading Arr Line Items

ITEM 9B.

OTHER INFORMATION

None.

Rule 10b5-1 Arrangement Adopted [Flag]

false

Rule 10b5-1 Arrangement Terminated [Flag]

false

Non-Rule 10b5-1 Arrangement Adopted [Flag]

false

Non-Rule 10b5-1 Arrangement Terminated [Flag]

false

Note 9 - Business Segment Information (Details Textual) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Number of Operating Segments	2
Non-US [Member]
Long-Lived Assets	$ 23,709	$ 24,405

Note 1 - Summary of Operations and Significant Accounting Policies 1 (Details Textual) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($) shares	Dec. 31, 2022 USD ($) shares
Capitalized Contract Cost, Gross	$ 0	$ 0
Research and Development Expense, Gross	8,587	7,874
Customer Funded Research and Development Expense Included in Cost of Goods Sold	$ 1,056	$ 793
Number of Operating Segments	2
Share-Based Payment Arrangement, Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount \| shares	111,247	1,425,693
Restricted Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount \| shares	4,029	2,500
Incremental Common Shares Attributable to Dilutive Effect of Share-Based Payment Arrangements \| shares	0
Customer Concentration Risk [Member] \| Revenue Benchmark [Member]
Number of Major Customers	1	1
Customer Concentration Risk [Member] \| Revenue Benchmark [Member] \| Large Defense Primary Contractor, 1 [Member]
Concentration Risk, Percentage	15.00%	17.00%
Customer Concentration Risk [Member] \| Revenue Benchmark [Member] \| Large Defense Primary Contractor, 1 [Member] \| Battery & Energy Products Segment [Member]
Concentration Risk, Percentage	18.00%	19.00%
Minimum [Member]
Standard Product Warranty, Period	90 days
Maximum [Member]
Standard Product Warranty, Period	3 years
Extended Warranty Contracts [Member]
Extended Product Warranty, Period	8 years
Revenue, Remaining Performance Obligation, Amount	$ 1,407

Note 3 - Supplemental Balance Sheet Information - Amortization of Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Amortization of intangible assets	$ 889	$ 1,282
Research and Development Expense [Member]
Amortization of intangible assets	97	97
Selling, General and Administrative Expenses [Member]
Amortization of intangible assets	$ 792	$ 1,185

Note 7 - Operating Leases

12 Months Ended

Dec. 31, 2023

Lessee, Operating Leases [Text Block]

Note 7 – Operating Leases

The Company has operating leases predominantly for operating facilities. As of December 31, 2023, the remaining lease terms on our operating leases range from approximately one (1) year to nine (9) years. Lease terms include renewal options reasonably certain of exercise. There is no transfer of title or option to purchase the leased assets upon expiration. There are no residual value guarantees or material restrictive covenants.

The components of lease expense for the current and prior-year comparative periods were as follows:

	Year ended December 31,
	2023		2022
Operating lease cost	$	1,016	$	894
Variable lease cost		114		95
Total lease cost	$	1,130	$	989

Supplemental cash flow information related to leases was as follows:

	Year ended December 31,
	2023		2022
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$	1,036	$	908
Right-of-use assets obtained in exchange for lease liabilities:	$	2,192	$	476

Supplemental balance sheet information related to leases was as follows:

		December 31,
	Balance Sheet Classification	2023			2022
Assets:
Operating lease right-of-use asset	Other noncurrent assets	$	3,589		$	2,187

Liabilities:
Current operating lease liability	Accrued expenses and other current liabilities	$	894		$	895
Operating lease liability, net of current portion	Other noncurrent liabilities		2,644			1,307
Total operating lease liability		$	3,538		$	2,202

Weighted-average remaining lease term (years)			5.3			4.7

Weighted-average discount rate			4.5	%		4.5	%

Future minimum lease payments as of December 31, 2023 are as follows:

Maturity of Operating Lease Liabilities
2024	$	894
2025		698
2026		624
2027		644
2028		648
Thereafter		463
Total lease payments	$	3,971
Less: Imputed interest		(433	)
Present value of remaining lease payments	$	3,538

Note 8 - 401(k) Retirement Benefit Plan

12 Months Ended

Dec. 31, 2023

Retirement Benefits [Text Block]

Note 8 - 401(k) Retirement Benefit Plan

We maintain a defined contribution 401(k) plan covering substantially all employees. Employees can contribute a portion of their salary or wages as prescribed under Section 401(k) of the Internal Revenue Code and, subject to certain limitations, we may, at the discretion of our Board of Directors, authorize an employer contribution based on a portion of the employees' contributions. For the years ended December 31, 2023 and 2022, the Company matched 100% on the first 3% and 50% on the next 2% contributed by the employee, or a maximum of 4% of the employee’s income. For 2023 and 2022, we contributed $678 and $600, respectively, to the 401(k) plan.

The entire disclosure for retirement benefits.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Note 5 - Stock-based Compensation (Tables)

12 Months Ended

Dec. 31, 2023

Disclosure of Share-Based Compensation Arrangements by Share-Based Payment Award [Table Text Block]

	Year ended December 31,
	2023		2022
Stock options	$	522	$	761
Restricted stock		6		15
Total	$	528	$	776

Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

	Year ended December 31,
	2023			2022
Risk-free interest rate		4.1	%		4.2	%
Volatility factor		57	%		50	%
Weighted average expected life (years)		4.9			4.8
Forfeiture rate		10.0	%		10.0	%
Dividends		0.0	%		0.0	%

Share-Based Payment Arrangement, Option, Activity [Table Text Block]

Year ended December 31, 2023
	Number of shares			Weighted average exercise price per share		Weighted average remaining contractual term		Aggregate intrinsic value
Shares under option – January 1		1,425,693		$	6.72
Options granted		231,650			6.69
Options exercised		(254,393	)		5.83
Options forfeited or expired		(152,355	)		5.06
Shares under option – December 31		1,250,595		$	7.10		3.97	$	515
Vested and expected to vest - December 31		1,151,228		$	7.17		3.79	$	452

Options exercisable – December 31		789,209		$	7.56		2.69	$	241

Year ended December 31, 2022
	Number of shares			Weighted average exercise price per share
Shares under option – January 1		1,306,824		$	6.87
Options granted		289,950			5.42
Options exercised		(59,500	)		3.82
Options forfeited or expired		(111,581	)		6.56
Shares under option – December 31		1,425,693		$	6.72

Options exercisable – December 31		881,804		$	7.13

Share-Based Payment Arrangement, Option, Exercise Price Range [Table Text Block]

			Option outstanding						Options exercisable
Range of exercise prices			Number of outstanding options		Weighted- average remaining contractual life		Weighted- average exercise price		Number of options exercisable		Weighted- average exercise price
$4.07	-	$6.36		338,364		4.79	$	5.42		156,099	$	5.54
$6.51	-	$6.84		353,733		5.54		6.71		134,583		6.51
$6.97	-	$8.25		334,165		2.89		7.64		290,355		7.74
$8.45	-	$9.96		224,333		1.88		9.44		208,172		9.51

$4.07	-	$9.96		1,250,595		3.97	$	7.10		789,209	$	7.56

Note 6 - Income Taxes - United States and Foreign Income (Loss) From Continuing Operations Before Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
United States	$ 7,294	$ (2,771)
Foreign	1,823	2,325
Loss before income taxes	$ 9,117	$ (446)

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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Note 9 - Business Segment Information (Tables)

12 Months Ended

Dec. 31, 2023

Schedule of Segment Reporting Information, by Segment [Table Text Block]

	Battery & Energy Products		Communications Systems		Corporate			Total
Revenue	$	129,953	$	28,691	$	-		$	158,644
Segment contribution		30,775		8,425		(29,725	)		9,475
Other expense, net						358			358
Income tax provision						1,951			1,951
Non-controlling interest						(31	)		(31	)
Net loss attributable to Ultralife								$	7,197

Total assets	$	124,411	$	28,873	$	24,992		$	178,276
Capital expenditures	$	2,064	$	118	$	370		$	2,552
Goodwill	$	26,078	$	11,493	$	-		$	37,571
Depreciation and amortization of intangible assets	$	3,336	$	183	$	392		$	3,911
Stock-based compensation	$	336	$	74	$	118		$	528

	Battery & Energy Products		Communications Systems		Corporate			Total
Revenue	$	119,995	$	11,845	$	-		$	131,840
Segment contribution		26,154		3,246		(29,271	)		129
Other expense, net						575			575
Income tax benefit						(326	)		(326	)
Non-controlling interest						(1	)		(1	)
Net loss attributable to Ultralife								$	(119	)

Total assets	$	117,017	$	29,424	$	21,989		$	168,430
Capital expenditures	$	1,371	$	81	$	227		$	1,679
Goodwill	$	25,935	$	11,493	$	-		$	37,428
Depreciation and amortization of intangible assets	$	3,761	$	261	$	437		$	4,459
Stock-based compensation	$	396	$	82	$	298		$	776

Schedule of Revenues from External Customers by Business Segment Sector [Table Text Block]

	Total Revenue		Commercial			Government/ Defense
Battery & Energy Products	$	129,953	$	100,842		$	29,111
Communications Systems		28,691		-			28,691
Total	$	158,644	$	100,842		$	57,802
				64	%		36	%

	Total Revenue		Commercial			Government/ Defense
Battery & Energy Products	$	119,995	$	93,045		$	26,950
Communications Systems		11,845		-			11,845
Total	$	131,840	$	93,045		$	38,795
				71	%		29	%

	Total Revenue		United States			Non-United States
Battery & Energy Products	$	129,953	$	64,120		$	65,833
Communications Systems		28,691		17,276			11,415
Total	$	158,644	$	81,396		$	77,248
				51	%		49	%

	Total Revenue		United States			Non-United States
Battery & Energy Products	$	119,995	$	58,820		$	61,175
Communications Systems		11,845		9,094			2,751
Total	$	131,840	$	67,914		$	63,926
				52	%		48	%

Note 5 - Stock-based Compensation - Non-cash Stock Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Stock options	$ 528	$ 776
Share-Based Payment Arrangement, Option [Member]
Stock options	522	761
Restricted Stock [Member]
Stock options	$ 6	$ 15

Note 3 - Supplemental Balance Sheet Information - Summary of Goodwill (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($)
Balance – January 1, 2022	$ 37,428
Effect of foreign currency translation	143
Balance – December 31, 2022	37,571
Battery & Energy Products Segment [Member]
Balance – January 1, 2022	25,935
Effect of foreign currency translation	143
Balance – December 31, 2022	26,078
Communications Systems Segment [Member]
Balance – January 1, 2022	11,493
Effect of foreign currency translation	0
Balance – December 31, 2022	$ 11,493

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References + Details

Note 4 - Commitments and Contingencies (Details Textual) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($)
Minimum [Member]
Standard Product Warranty, Period	90 days
Maximum [Member]
Standard Product Warranty, Period	3 years
Capital Addition Purchase Commitments [Member]
Long-Term Purchase Commitment, Amount	$ 890

Note 9 - Business Segment Information

12 Months Ended

Dec. 31, 2023

Segment Reporting Disclosure [Text Block]

Note 9 - Business Segment Information

We report our results in two operating segments: Battery & Energy Products and Communications Systems. The Battery & Energy Products segment includes Lithium 9-volt, cylindrical and various other non-rechargeable batteries, in addition to rechargeable batteries, uninterruptable power supplies, charging systems and accessories. The Communications Systems segment includes RF amplifiers, power supplies, cable and connector assemblies, amplified speakers, equipment mounts, case equipment, man-portable systems, integrated communication systems for fixed or vehicle applications and communications and electronics systems design. We believe that reporting performance at the gross profit level is the best indicator of segment performance.

2023:

	Battery & Energy Products		Communications Systems		Corporate			Total
Revenue	$	129,953	$	28,691	$	-		$	158,644
Segment contribution		30,775		8,425		(29,725	)		9,475
Other expense, net						358			358
Income tax provision						1,951			1,951
Non-controlling interest						(31	)		(31	)
Net loss attributable to Ultralife								$	7,197

Total assets	$	124,411	$	28,873	$	24,992		$	178,276
Capital expenditures	$	2,064	$	118	$	370		$	2,552
Goodwill	$	26,078	$	11,493	$	-		$	37,571
Depreciation and amortization of intangible assets	$	3,336	$	183	$	392		$	3,911
Stock-based compensation	$	336	$	74	$	118		$	528

2022:

	Battery & Energy Products		Communications Systems		Corporate			Total
Revenue	$	119,995	$	11,845	$	-		$	131,840
Segment contribution		26,154		3,246		(29,271	)		129
Other expense, net						575			575
Income tax benefit						(326	)		(326	)
Non-controlling interest						(1	)		(1	)
Net loss attributable to Ultralife								$	(119	)

Total assets	$	117,017	$	29,424	$	21,989		$	168,430
Capital expenditures	$	1,371	$	81	$	227		$	1,679
Goodwill	$	25,935	$	11,493	$	-		$	37,428
Depreciation and amortization of intangible assets	$	3,761	$	261	$	437		$	4,459
Stock-based compensation	$	396	$	82	$	298		$	776

Long-lived assets (comprised of property, plant and equipment; goodwill; and other intangible assets) held outside the U.S., principally in Canada, United Kingdom and China, were $23,709 and $24,405 as of December 31, 2023 and 2022, respectively.

The following tables disaggregate our business segment revenues by major source and geography.

Commercial and Government/Defense Revenue Information:

Year ended December 31, 2023:

	Total Revenue		Commercial			Government/ Defense
Battery & Energy Products	$	129,953	$	100,842		$	29,111
Communications Systems		28,691		-			28,691
Total	$	158,644	$	100,842		$	57,802
				64	%		36	%

Year ended December 31, 2022:

	Total Revenue		Commercial			Government/ Defense
Battery & Energy Products	$	119,995	$	93,045		$	26,950
Communications Systems		11,845		-			11,845
Total	$	131,840	$	93,045		$	38,795
				71	%		29	%

U.S. and Non-U.S. Revenue Information¹:

Year ended December 31, 2023:

	Total Revenue		United States			Non-United States
Battery & Energy Products	$	129,953	$	64,120		$	65,833
Communications Systems		28,691		17,276			11,415
Total	$	158,644	$	81,396		$	77,248
				51	%		49	%

Year ended December 31, 2022:

	Total Revenue		United States			Non-United States
Battery & Energy Products	$	119,995	$	58,820		$	61,175
Communications Systems		11,845		9,094			2,751
Total	$	131,840	$	67,914		$	63,926
				52	%		48	%

¹Sales classified to U.S. include shipments to U.S.-based prime contractors which in some cases may serve non-U.S. projects.

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.