<PAGE>
                                                                   EXHIBIT 10(u)

                              Engagement Agreement

This engagement agreement is made between Power Technology, Inc. (the Company)
and Battery Consultation Services, represented by Dr. Basanta K. Mahato
(Consultant).

Pursuant to Consultant's efforts to assist the Company in achieving its goals
with regard to commercializing its proprietary technology for batteries using
reticulated foam and for good consideration, the Company employs CONSULTANT on
the following terms and conditions:

1.       The Company hereby contracts with the CONSULTANT for certain technical
         assistance in the ongoing development of its batters prototypes being
         produced by BC Research; this agreement with CONSULTANT will begin in
         November 2001 and shall continue for a minimum of three months at which
         time the parties will determine the terms of a more formal agreement.

2.       The Company shall pay CONSULTANT a monthly retainer of $4,000 USD,
         payable in the Company's stock at the offering price at the end of each
         month during the term of this agreement.

3.       the Company agrees to issue80,000 shares of its common stock to the
         CONSULTANT for the purchase of an advanced battery paste formula owned
         by the CONSULTANT that can be integrated with the Company's patented
         technology.

4.       Upon the successful commercialization of this jointly developed
         battery, the Company will issue $110,000 USD payable in shares at the
         closing offer price pursuant to rule 144-investment letter stock to
         CONSULTANT for his participation in the development of the combined
         technologies.

5.       CONSULTANT will devote adequate time, attention and energies to the
         business of the Company during this engagement, CONSULTANT will not
         engage in any competing business activity, regardless of whether such
         activity is pursued for profit, gain or other pecuniary advantage,
         CONSULTANT is not prohibited from making personal investments in any
         other business provided those investments do not compete with the
         Company.

6.       CONSULTANT agrees no to reveal any confidential information or trade
         secrets to any person, firm, corporation, or entity.

7.       CONSULTANT may incur reasonable expenses for furthering the Company's
         business. The Company shall reimburse CONSULTANT for all business
         expenses pursuant to Company policy.

8.       Without cause, the Company may terminate this contract anytime with one
         month written notice.

9.       Any claim or controversy that arises out of or relates to this
         engagement agreement, or breach of the same, shall be settled by
         arbitration in accordance wit the rules of the American Arbitration
         Association.

10.      This instrument is the only agreement and it may only be altered by
         written agreement of the parties.

Signed this 1st day of November, 2001.

s/ Lee Balak                                      s/ Basanta K. Mahato
----------------------------                      -----------------------------
Power Technology, Inc.                            Dr. Basanta K. Mahato
Lee Balak, President                              Battery Consultation Services