<PAGE>

                                                                 EXHIBIT 10.23


                     INVENTORY MANAGEMENT SERVICE AGREEMENT


                                      between


                             TANISYS TECHNOLOGY, INC. 
                              12201 Technology Blvd.
                                 Austin, TX 78727
                                       U.S.A.


                                        and


                              SIEMENS COMPONENTS, INC.
                             10950 North Tantau Avenue
                                Cupertino, CA 95014
                                       U.S.A.




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                              INDEX TO AGREEMENT:


BASIC AGREEMENT:    SIEMENS - TANISYS

ATTACHMENT A:       Products

ATTACHMENT B:       Siemens Fiscal Calendar Cutoff Dates

ATTACHMENT C:       Cost Basis and Pricing Structure

ATTACHMENT D:       Compaq-specific Warehouse Requirements

ATTACHMENT E:       EDI Agreement




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                INVENTORY MANAGEMENT SERVICE AGREEMENT

This agreement is made effective November 1, 1996 between Tanisys Technology, 
Inc. 12201 Technology Blvd., Austin, TX 78727, U.S.A (TANISYS) and Siemens 
Components, Inc. 10950 North Tantau Avenue, Cupertino, CA 95014 (SIEMENS).

In consideration of the mutual covenants and agreements set forth below, the 
parties agree as follows.

1. TANISYS WILL PROVIDE THE FOLLOWING:

  a) Inventory receiving and dispatching including notification to SIEMENS in
     case of shipping damage.

  b) Storage area in a warehouse facility located at the TANISYS manufacturing
     facility at 12201 Technology Blvd. Suite 130, Austin Texas.

  c) On demand delivery service to locations of SIEMENS, SIEMENS customers, 
     or any other location which SIEMENS requires.  See Attachment D for 
     details of customers.

  d) Inventory reports to SIEMENS via EDI per Article 11 below, and per 
     Attachment E.

  e) Insurance per Article 16 below, if so required by SIEMENS.

  f) All licenses and permits required to comply with all applicable U.S. 
     federal, state and local laws and regulations, for services rendered.

  g) TANISYS will make shipments to locations as stated above in accordance 
     with SIEMENS' releases, provided per the EDI daily shipment instructions 
     as generated by  SIEMENS.

  h) TANISYS will deviate from the above planned shipments only upon receipt 
     of a telephone call request confirmed by FAX signed by an authorized 
     SIEMENS representative. TANISYS agrees to document to the best of their 
     ability any such deviations and to report the actual shipments made, 
     via EDI daily 856 Ship Notice/Manifest.

  i) Deliveries by TANISYS to SIEMENS customers may require SIEMENS-generated 
     ASNs to SIEMENS customers. SIEMENS will retrieve from the SIEMENS 
     mailbox, each morning or as required, the Receiving Advice 
     (EDI 861) from SIEMENS customers covering shipments made by TANISYS on 
     behalf of SIEMENS.

2. SIEMENS WILL PROVIDE THE FOLLOWING:

  a) Payment for the services performed in each calendar month during the term 
     of this Agreement will be made to TANISYS within thirty (30) calendar days
     of SIEMENS' receipt of invoice from TANISYS.   All amounts in this 
     Agreement are in U.S. dollars.

  b) Monthly service charges shall be as agreed and documented in Attachment C 
     "Cost Basis and Pricing Structure".


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3. TERMINATION AND DISCRETION:

  a) This Agreement may be terminated by SIEMENS for any reason in its sole 
     discretion upon thirty (30) days advance written notice to TANISYS. Such 
     termination will be with no cost or obligation to SIEMENS, except for 
     SIEMENS' obligation to remove all of its product from the premises of
     TANISYS within thirty (30) days after such termination.  SIEMENS further 
     agrees to bear the cost of storage, packing and moving.

  b) This Agreement may be terminated by TANISYS for any reason at its sole 
     discretion upon ninety (90) days advance written notice to SIEMENS.

4. TERMINATION FOR CAUSE:

If for any reason SIEMENS, in its sole opinion, determines that TANISYS is 
not performing this Agreement in a satisfactory manner, including but not 
limited to, not delivering product according to SIEMENS requests, delivering 
short or wrong quantities, losing inventory, failure to report in a timely 
manner, or failure to complete billings or receipts in a timely manner; 
SIEMENS will give TANISYS written notice of such default and TANISYS will 
have ten (10) days to cure the default after receipt of the written notice.  
If not cured, SIEMENS may immediately terminate this Agreement without 
further notice. If SIEMENS so terminates the Agreement, TANISYS will 
immediately return to SIEMENS whatever parts remain in TANISYS' inventory or 
direct the inventory to be shipped to a successor firm or any other location 
as SIEMENS requires. 

5. RELATIONSHIP BETWEEN PARTIES:

  a) This Agreement is not intended to and does not create any employer/
     employee relationship between the parties. TANISYS is and shall remain 
     an independent contractor providing a service to SIEMENS. TANISYS agrees 
     that in the context of the service it is rendering to SIEMENS that it will 
     not claim or represent that it is operating or doing business as a SIEMENS 
     sales office, nor will it purport to pledge the credit of, or enter into 
     any contract for, or on behalf of SIEMENS.

  b) This Agreement does not convey, nor shall TANISYS claim, any property 
     interest in SIEMENS' corporate name, trademarks, trade names or patents, 
     or other proprietary rights. TANISYS shall indemnify and hold SIEMENS 
     harmless from all claims, demands, suits, and actions for damages to 
     property or persons, including legal or attorney's fees incurred by 
     SIEMENS made by any third party resulting from TANISYS' negligence or 
     willful misconduct in providing these services. This obligation to 
     indemnify shall survive the termination of this Agreement.

  c) Neither SIEMENS nor TANISYS shall be liable for failure to perform any 
     obligation under this Agreement if such failure is caused by circumstances 
     not directly under such party's reasonable control, including, but not 
     limited to, failures resulting from acts of God, acts of public 
     authorities, war and war measures, strikes, fires, failures or delays of 
     suppliers or carriers, inability to obtain materials or supplies, demand 
     for products within the forecast period over available supply, regulations 
     under Agreements between governments or any interruption for any reason in 
     the manufacture of products by suppliers.

6. TANISYS WILL ALSO DO THE FOLLOWING:

  a) TANISYS agrees to provide and maintain, without expense to SIEMENS, a 
     suitable place of business with adequate facilities including a monitored 
     security alarm system and sufficient personnel for the timely receiving 
     and delivery of the products to SIEMENS' customers. "Products" for 
     purposes of this Agreement shall include those referred to in Attachment 
     A "Products" and such others as SIEMENS may decide to add into its 
     shipments under the terms 


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     of the Agreement. TANISYS shall provide secure and segregated areas for 
     consigned and finished goods conspicuously marked as SIEMENS areas.

  b) TANISYS shall maintain and use its facilities in such a manner as to 
     ensure proper care for SIEMENS products, including at a minimum, proper 
     temperature and humidity controls, proper anti-static equipment, and 
     proper facilities to permit incoming, outgoing or other inspection of 
     product.  TANISYS shall maintain and use its facilities to ensure prompt 
     handling of orders and shipments, careful attention to customer 
     complaints, and servicing for all products covered by this Agreement.

  c) TANISYS shall maintain records of inventory, shortages, receiving and 
     shipments of products and make such records available to SIEMENS or its 
     representatives upon request during normal business hours to make certain 
     that all of the requirements of this Agreement such as facilities,
     personnel and record integrity are being met.

7.  PRODUCTS:

  a) TANISYS agrees to coordinate shipment of product to specified customers 
     upon notification and approval by SIEMENS.

  b) SIEMENS shall not be required to provide TANISYS any products.

  c) SIEMENS may issue revisions to Attachment A from time to time to keep 
     TANISYS informed of current products to be delivered.

8.  TITLE AND SHIPMENT RESPONSIBILITIES:

  a) SIEMENS may withdraw any product with reasonable notice of 24 hours to 
     TANISYS.

  b) Inventories will be subject to verification and audit by SIEMENS or its 
     designated representative. All inventory shrinkage at TANISYS will be 
     charged directly to TANISYS and invoiced accordingly to TANISYS.

  c) SIEMENS retains title in all products while in the TANISYS warehouse.

  d) Notwithstanding (b) above, but subject to Articles 16 and 17 below, 
     SIEMENS will bear risk of loss for the inventory (except for losses 
     attributable to the willful or negligent act of TANISYS) until it is 
     signed for by SIEMENS' customer.

  e) All shipments from SIEMENS to TANISYS will be made such that SIEMENS 
     pays freight costs. SIEMENS is responsible for filing any freight 
     claims that might arise.  All deliveries from TANISYS to SIEMENS' 
     customers will be made by TANISYS at SIEMENS' customer's or SIEMENS 
     direct expense, as instructed by SIEMENS.

9.  INVENTORY:


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  a) TANISYS will maintain the inventory of products furnished by SIEMENS and 
     will cooperate with SIEMENS in periodic reviews of inventory based on 
     daily, weekly and monthly inventory report submissions.

  b) Upon request by SIEMENS,  TANISYS will complete cycle count verification 
     and audit within 24 hours of request, and will submit to SIEMENS a 
     written reconciliation including historical activity for identified 
     variances within 3 working days of the request.

10.  RETURNS:

TANISYS, under this Service Agreement, shall bear responsibility for returns 
as outlined below.  

  a) In the event of damaged or functional rejects by SIEMENS' customers, 
     TANISYS will accept returns, provided that such returns are authorized by 
     SIEMENS.

  b) TANISYS shall make an evaluation as to the reason for product failure. In 
     case of a manufacturing defect caused by TANISYS in assembly, TANISYS 
     shall rework or replace at TANISYS' expense any defective product and 
     will ship at TANISYS' expense such replacement product to SIEMENS' 
     customer. Additional services rendered by TANISYS for rework, test and 
     repair for other than TANISYS' processed activity will be available to 
     SIEMENS as per Attachment F.

  c) Any product deemed by TANISYS to have failed due to SIEMENS component 
     failure shall be transferred to scrap inventory, and recorded as such in 
     TANISYS' inventory, until advised by SIEMENS as to disposition.

11.  REPORTS:

  a) TANISYS will provide same-day notification to SIEMENS of shipments to
     SIEMENS customers' location by product and ident number.  In addition,
     TANISYS shall submit a shipment report, by product and ident number, no
     later than the Monday following the end of the SIEMENS fiscal month.  The
     report shall provide a listing of shipments during that month, identified
     by part number, product ident number (BNR), ASN number and date, quantity
     shipped and balance of product held by as inventory. (See Attachment B:
     SIEMENS Fiscal Month Ending Dates).

  b) Daily transmissions shall occur via EDI 846 transactions for SIEMENS'
     defined stock, including but not limited to on-hand consigned quantities
     of loose parts, work in process (WIP), rework, scrap, finished stock,
     cumulative to-date shipments, "red flag" critical issues, and running
     perpetual inventory listings.

  c) TANISYS will work with SIEMENS to track performance indicators such as
     data integrity and timeliness of data entry.  Through continuous
     improvement and a team-oriented problem solving approach, SIEMENS and
     TANISYS will ensure the quality of service expected in this Agreement.

12.  ASSIGNMENT:

TANISYS shall not delegate any duties or assign any rights under this 
Agreement or any interest herein without SIEMENS prior written consent, which 
may be granted or withheld at the sole discretion of SIEMENS; otherwise such 
may, at SIEMENS' option, be deemed to be a termination of this Agreement by 
TANISYS. The merger or consolidation of  TANISYS, or any other transaction 
effecting a substantial change in the ownership or control of TANISYS, shall 
be deemed at SIEMENS' option an


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assignment requiring prior written consent by SIEMENS.  This Agreement may be 
assigned by SIEMENS to such other corporations as may be incorporated in 
North America and deemed by SIEMENS to be the appropriate corporation(s) to 
succeed TANISYS.

13.  DURATION AND TERMINATION:

  a) This Agreement shall commence on the date first written above and unless 
     terminated, in accordance with the terms hereof, shall remain in effect 
     until December 31, 1997.  Either party may decline to renew this Agreement 
     with or without cause (in the sole discretion of that party) by giving
     at least ninety (90) days' prior written notice of that party's election 
     to decline to renew.  If no such notice is given, this Agreement shall 
     be deemed to be renewed and extended on a yearly basis.  Neither party 
     makes any promise nor is under any obligation, expressly or implied, to 
     renew this Agreement upon its expiration.

  b) If TANISYS should become insolvent or take or have brought against it 
     bankruptcy proceedings or if a distress or analogous process is levied 
     against all or part of its property, or if a receiver for their property 
     or a substantial part thereof shall be appointed, SIEMENS may at its 
     option terminate this Agreement by giving notice of its election to do so 
     and such termination shall be effective on the date notice is given.

  c) Upon termination of this Agreement, TANISYS agrees to return to SIEMENS 
     and SIEMENS shall accept return of any and all SIEMENS, inventory of those
     SIEMENS products which were listed on TANISYS, last daily inventory 
     report, inclusive of receipts and shipments made after the previous 
     days' closing date. TANISYS agrees that, upon such termination, it will 
     ship such inventory FCA shipping point, freight collect to SIEMENS as 
     SIEMENS shall direct.

  d) Acceptance of any order from or the shipment of any product to TANISYS 
     after termination shall not be construed as a renewal or extension of 
     the Agreement nor as a waiver of any termination notice.

14.  CONFIDENTIALITY:

14.1  "Confidential Information" shall mean all such technical information as 
      well as know-how (given orally, in writing or in other tangible form) 
      necessary for the manufacture of Products, which one party shares with
      the other.  "Confidential Information" includes the specification
      necessary for the procurement of the components required for the
      manufacture of Products, with the exception of DRAMs, as defined in
      Attachment A.

14.2  The parties undertake to keep secret, even after termination of this 
      Agreement, Confidential Information furnished hereunder insofar as, and
      as long as, it has not otherwise lawfully come into the public domain or
      the party which disclosed the information has not consented in writing 
      that it may be disclosed to third parties.

14.3 The parties further agree that it will only use Confidential Information 
      supplied under this Agreement for purposes set forth in this Agreement.


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14.4  Information shall not be subject to the above confidentiality provisions
      to the extent that a party can demonstrate that the information

  - is known to or is in the possession of that party before transmission by 
    the other party;

  - became legally available to that party from a source other than the other 
    party or is in or passed into the public domain other than by reach of 
    this Agreement;

  - is developed independently by that party;

  - the disclosure of which is expressly authorized by the other party.

14.5  Except as required by law, neither party shall disclose the existence 
      of this Agreement, including insurance coverage and values thereunder,
      except as mutually agreed.

15. SCOPE OF AGREEMENT:

  a) This Agreement supersedes and cancels any previous understanding or 
     agreement between the parties relating to the Services to be provided.  
     There are no other inventory management or warehousing terms and 
     conditions, representations or undertakings, except those set forth in this
     Agreement.  No other agreement or understanding purporting to modify or 
     supplement this Agreement, nor any promises made by a party's 
     representative shall be binding upon that party unless confirmed in 
     writing by a duly authorized representative of that party.

  b) The failure of a party to enforce at any time any of the provisions of 
     this Agreement, or any right with respect thereto, shall not be construed 
     as a waiver of such provisions or rights or any other provision or right.

  c) This Agreement becomes binding only when executed by both parties.

16.  INSURANCE:

  a) TANISYS may at SIEMENS' request procure and maintain comprehensive general 
     liability insurance including property damage with limits of not less 
     than $XXXXXX (XXXXXX Dollars) Property Coverage with A+ rated companies, 
     which covers both the Manufacturing Agreement Section 11 and this 
     Agreement. In such case, SIEMENS shall be an additional named insured 
     in all such policies. TANISYS shall provide current certificates of 
     such insurance. Under no conditions may such insurance be modified, 
     canceled and/or replaced without thirty (30) days advanced written 
     notice to SIEMENS.  SIEMENS reserves the right to carry such general 
     comprehensive liability insurance concurrent with existing SIEMENS 
     insurance policies in effect.

  b) TANISYS shall be fully liable for any and all damages caused due to breach 
     of this section.

17.  SECURITY INTEREST and WAREHOUSE RECEIPT:

  a) Upon TANISYS receiving products and signing a "Warehouse Receipt" for any 
     given shipment, the quantity and description thereon will be deemed an 
     absolute indication that TANISYS has accepted risk of loss for that 
     quantity of that item.  The only exception will be that TANISYS will be
     allowed until the close of business twenty-four (24) hours after receipt 
     of any given shipment to advise in writing (by FAX) as to any 
     discrepancies at the carton level; within forty-eight (48) hours at the 
     partnumber and ident number detail level.
   
     All such notifications are to include:

     1) Packing List number (or similar identification)
     2) Number of cartons received


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     3) Nature of discrepancy
     4) Date shipped from SIEMENS.

  b) There will be no requirement for SIEMENS to prove negligence in order to 
     obtain reimbursement, if any product, or any portion thereof, is, for any 
     reason whatever, subsequently found to have been lost, stolen or damaged 
     while under the control of TANISYS.

  c) TANISYS shall not, under any circumstances, pledge as collateral any 
     SIEMENS product in any undertaking, and/or hypothecate any of the products 
     entrusted in its care.

  d) TANISYS shall complete and forward daily all inventory transactions, 
     receipts, and ASN activity detail to SIEMENS via EDI, Internet or FAX 
     within one (1) hour of the close of TANISYS' normal business day (no 
     later than 5:00 P.M. Central Standard Time).

18.  NOTICES:

All notices required to be made thereunder shall be given by (a) Registered 
or first-class mail, return receipt requested, or (b) Telecommunications - 
EDI, Internet or FAX.  Notices given under clause (a) shall be deemed to be 
given on the fifth day after mailing.  Notices given under clause (b) shall 
be deemed to be given when transmitted unless transmitted after ordinary 
business hours of the party to be noticed, in which case it shall be deemed 
to be given on the next business day.

19.  ARBITRATION:

19.1  SIEMENS and TANISYS shall attempt in good faith to resolve any dispute 
      arising out of or relating to this Agreement promptly by negotiation
      between executives who have authority to settle the controversy.  The
      executive will be at the CEO, CFO or COO level and will not have had
      direct responsibility for administration of this Agreement. Either party
      may give the other written notice of any dispute not resolved in the
      ordinary course of business. Within fifteen (15) days after delivery of
      the notice the party receiving the notice shall submit to the other a
      written response.

      The notice and response shall include a statement of the party's positions
      regarding the matter in dispute, a summary of arguments in support, and
      the name and title of the executive who will represent that party and any
      other person who will accompany that executive.  Within 30 days after 
      delivery of the initial notice, the designated executives shall meet at a
      mutually acceptable time and place, and thereafter as often as they
      reasonably deem necessary to attempt to resolve the dispute. All
      reasonable request for information made by one party to the other shall
      be honored in a timely fashion.

      All negotiations conducted pursuant to this Section 19 (and any of the 
      party's submissions in contemplation hereof) shall be kept confidential
      by the parties and shall be treated by the parties and their respective 
      representatives as compromise and settlement negotiations for purposes 
      of the Federal Rules of Evidence and any similar state rules.

19.2  If any matter in dispute arising under this Agreement has not been 
      resolved within sixty (60) days after delivery of the notice or if the 
      parties fail to meet within thirty days (30) days, the matter will be 
      submitted to binding arbitration. Either party may initiate binding 
      arbitration as contemplated herein.


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      Either party (the  claimant) may give written notice to the other 
      (respondent) of its intention to arbitrate, which notice shall contain 
      a statement setting forth the nature of the dispute, the amount involved,
      if any, and the remedy sought, and file with the appropriate office of the
      American Arbitration Association three copies of the notice and three
      copies of the arbitration provision of this Agreement, together with the
      appropriate filing fee as provided in the Schedule on page 21 of the AAA
      Commercial Rules as Amended and Effective on November 2, 1993.

      The AAA shall give notice of such filing to the respondent which may file
      an answering statement in duplicate with the AAA within ten days after 
      notice from the AAA, in which event the respondent shall at the same time
      send a copy of the answering statement to the claimant. If a counterclaim
      is asserted, it shall contain a statement setting forth the nature of the
      counterclaim, the amount involved, if any, and the remedy sought. If a 
      counterclaim is made, the appropriate fee shall be forwarded to the AAA
      with the answering  statement. If no answering statement is filed within
      the stated time, it will be treated as a denial of the claim. Failure to
      file an answering statement shall not operate to delay the arbitration.

19.3  The AAA Commercial Arbitration Rules, as modified or revised by the 
      provisions herein, shall govern these proceedings. The arbitration shall
      be conducted by three arbitrators, one selected by each party and the
      third selected by those two arbitrators. After the arbitrators are
      selected, the parties agree to try in good faith to settle the dispute by
      mediation administered by the American Arbitration Association under its
      Commercial Mediation Rules.

19.4  The place of the arbitration proceedings shall be San Francisco, 
      California if TANISYS initiates the arbitration and in Austin, Texas if 
      SIEMENS initiates the arbitration. The decision of the arbitration panel
      shall be rendered in writing.

19.5  The parties agree that procedural rules will be those of the State in 
      which the arbitration is to occur, as amended by this Agreement. In
      addition, the parties agree that discovery will take place informally
      to the extent possible through document production, interrogatories
      limited to identification of witnesses and documents and no more than
      five (5) depositions per side.

20.  SUBSTANTIVE LAW:

All disputes shall be settled in accordance with the provisions of this 
Agreement and all other Agreements regarding its performance, in accordance 
with the substantive law of the State identified in Section 19.4 (except for 
its conflict of laws provision) without reference to other law.  The United 
Nations Convention on contracts for the International Sale of Goods of 
April 1, 1980 shall not apply.

21.  LIMITATION OF LIABILITY:

NEITHER PARTY SHALL BE LIABLE TO THE OTHER FOR ANY INCIDENTAL, SPECIAL OR 
CONSEQUENTIAL DAMAGES THAT RESULT FROM PERFORMANCE UNDER THIS AGREEMENT, EVEN 
IF THE PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.


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IN WITNESS THEREOF, the parties hereto have caused this Service Agreement to 
be executed by their duly authorized representatives as of the date first 
written above.


TANISYS TECHNOLOGY, INC.               SIEMENS COMPONENTS, INC.

/s/ Gary W. Pankonien                  /s/ Kleinjan Du Preez
_________________________________      _________________________________
By                                     By

GARY W. PANKONIEN                      KLEINJAN Du PREEZ
_________________________________      _________________________________
Printed Name                           Printed Name

PRESIDENT & CHIEF OPERATING OFFICER    DIRECTOR,  MEMORY PRODUCTS
_________________________________      _________________________________
Title                                  Title

11/20/96                               11/20/96
_________________________________      _________________________________
Date                                   Date



/s/ Joe O. Davis                       /s/ Christiane Walter

JOE DAVIS                              CHRISTIANE WALTER

_________________________________      _________________________________
Printed Name                           Printed Name

CHIEF FINANCIAL OFFICER                DIRECTOR CORPORATE CONTROLLING

_________________________________      _________________________________
Title                                  Title

11/20/96                               11/21/96

_________________________________      _________________________________
Date                                   Date


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