UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                    FORM 8-K

                                 Current Report
     PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

               Date of Report (Date of earliest event reported):

                                  April 7, 2005

                            ULTRALIFE BATTERIES, INC.
                            -------------------------
             (Exact name of registrant as specified in its charter)

                                    Delaware
                                    --------
         (State or other jurisdiction of incorporation or organization)

          0-20852                                       16-1387013
          -------                                       ----------
 (Commission File Number)                  (I.R.S. Employer Identification No.)

                 2000 Technology Parkway, Newark, New York 14513
                 -----------------------------------------------
               (Address of principal executive offices) (Zip Code)

                                 (315) 332-7100
                                 --------------
              (Registrant's telephone number, including area code)


Check the appropriate box below if the Form 8-K filing is intended to
simultaneously satisfy the filing obligation of the registrant under any of the
following provisions:

[ ] Written communications pursuant to Rule 425 under the Securities Act
    (17 CFR 230.425)

[ ] Soliciting material pursuant to Rule 14a-12 under the Exchange Act
    (17 CFR 240.14a-12)

[ ] Pre-commencement communications pursuant to Rule 14d-2(b) under the
    Exchange Act (17 CFR 240.14d-2(b)

[ ] Pre-commencement communications pursuant to Rule 13e-4(c) under the
    Exchange Act (17 CFR 240.13e-4(c))

Item 7.01. Regulation FD Disclosure. Ultralife Batteries, Inc. (the "Company") estimates revenue for the first quarter ended April 2 will be approximately $15 million, based on a preliminary review of the results. The Company's press release is attached as Exhibit 99.1 to this Form 8-K, and the information set forth therein is furnished under Item 7.01. Item 9.01. Financial Statements, Pro Forma Financials and Exhibits. (a) Financial Statements of Business Acquired. Not applicable. (b) Pro Forma Financial Information. Not applicable. (c) Exhibits. 99.1 Press Release dated April 7, 2005. SIGNATURE Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. ULTRALIFE BATTERIES, INC. Dated: April 7, 2005 By: /s/ Robert W. Fishback ----------------------------- Vice President of Finance & Chief Financial Officer

INDEX TO EXHIBITS (99) Additional Exhibits 99.1 Press Release dated April 7, 2005.

                                                                    Exhibit 99.1

Ultralife Batteries, Inc. Announces Preliminary First Quarter Revenue;
    Reaffirms 2005 Revenue Guidance of 10% to 20% Growth over 2004

    NEWARK, N.Y.--(BUSINESS WIRE)--April 7, 2005--Ultralife Batteries,
Inc. (NASDAQ: ULBI) estimates revenue for the first quarter ended
April 2 will be approximately $15 million, based on a preliminary
review of the results.
    On March 15 the company announced a $7.4 million U.S. Defense
Department contract award for its BA-5390 batteries. Deliveries were
expected to occur in March and April. The company also indicated that
while a substantial portion of these deliveries was included in its
first quarter $18 million revenue guidance, due to the timing of the
receipt of this contract it was possible that some revenue might shift
into the second quarter, which has now occurred. In the first quarter,
approximately $2 million was recognized under this contract with the
remainder to be recognized in the second quarter.
    John D. Kavazanjian, Ultralife's president and chief executive
officer said, "Logistical issues at the customer's receiving location
prevented us from recognizing revenue under this contract award as
anticipated for the first quarter. This had the effect of shifting $3
million in revenue from the first to the second quarter along with the
corresponding margin. Those shipments were delivered this week and the
remainder of the contract deliveries will be completed in April.
Consequently, we are not changing our revenue outlook for the year."

    About Ultralife Batteries, Inc.

    Ultralife is a global provider of power solutions for diverse
applications. The company develops, manufactures and markets a wide
range of non-rechargeable and rechargeable batteries, charging systems
and accessories for use in military, industrial and consumer portable
electronic products. Through its range of standard products and
engineered solutions, Ultralife is able to provide the next generation
of power systems. Industrial, retail and government customers include
General Dynamics, Philips Medical Systems, Energizer, Kidde Safety,
Lowe's, Radio Shack and the national defense agencies of the United
States and United Kingdom, among others.
    Ultralife's headquarters, principal manufacturing and research
facilities are in Newark, New York, near Rochester. Ultralife (UK)
Ltd., a second manufacturing facility, is located in Abingdon, U.K.
Both facilities are ISO-9001 certified. Detailed information about
Ultralife is available at www.ultralifebatteries.com.

    This press release may contain forward-looking statements based on
current expectations that involve a number of risks and uncertainties.
The potential risks and uncertainties that could cause actual results
to differ materially include: worsening global economic conditions,
increased competitive environment and pricing pressures, disruptions
related to restructuring actions and delays. Further information on
these factors and other factors that could affect Ultralife's
financial results is included in Ultralife's Securities and Exchange
Commission (SEC) filings, including the latest Annual Report on Form
10-K.

    Ultralife(R) is a registered trademark of Ultralife Batteries,
Inc.

    CONTACT: Ultralife Batteries, Inc.
             Robert Fishback, 315-332-7100
             rfishback@ulbi.com
             or
             Lippert/Heilshorn & Associates, Inc.
             Investor Relations:
             Jody Burfening, 212-838-3777
             jburfening@lhai.com
             or
             Media:
             Chenoa Taitt, 212-201-6635
             ctaitt@lhai.com