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):

                               September 21, 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))


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Item 7.01. Regulation FD Disclosure.

Ultralife Batteries, Inc. (the "Company") has adjusted its outlook for revenue
in the second half of 2005 to approximately $35 million, consisting of
approximately $15 million for the third quarter and $20 million for the fourth
quarter, due to ongoing uncertainty regarding the timing and quantity of BA-5390
battery orders from the U.S. Defense Department for the reminder of this year.
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 September 21, 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:  September 21, 2005                   By: /s/Robert W. Fishback
                                                 -------------------------------
                                                 Robert W. Fishback
                                                 Vice President of Finance & CFO



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                                INDEX TO EXHIBITS

(99)     Additional Exhibits

         99.1     Press Release dated September 21, 2005.



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