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                                                                       EXHIBIT 5
                               December 6, 2000



Tanisys Technology, Inc.
12201 Technology Boulevard
Suite 125
Austin, Texas 78727-6101

Ladies and Gentlemen:

We have acted as counsel to Tanisys Technology, Inc., a Wyoming corporation (the
"Company"), in connection with the proposed issuance by the Company of (i) up to
5,000,000 shares of the Company's common stock, no par value ("Common Stock"),
upon exercise of options granted or to be granted under the Company's 1993 Stock
Option Plan, and (ii) up to 2,000,000 shares of Common Stock upon exercise of
options granted or to be granted under the Company's 1997 Non-Employee Director
Plan (all of such 7,000,000 shares being herein called the "Shares"; and the
1993 Stock Option Plan and the 1997 Non-Employee Director Plan being herein
called the "Plans").  The Company is filing with the Securities and Exchange
Commission (the "Commission") under the Securities Act of 1933, as amended (the
"Securities Act"), a Registration Statement on Form S-8 (the "Registration
Statement") relating to the Shares.

We have examined originals or copies of (i) the Restated Articles of
Incorporation of the Company, as amended, (ii) the Bylaws of the Company, as
amended, (iii) the Plans, (iv) certain resolutions of the Board of Directors of
the Company and (v) such other documents and records as we have deemed necessary
and relevant for purposes hereof.  In addition, we have relied on certificates
of officers of the Company as to certain matters of fact relating to this
opinion and have made such investigations of law as we have deemed necessary and
relevant as a basis hereof.  In such examination and investigation, we have
assumed the genuineness of all signatures, the authenticity of all documents,
certificates and records submitted to us as originals, the conformity to
authentic original documents, certificates and records of all documents,
certificates and records submitted to us as copies, and the truthfulness of all
statements of fact contained therein.

Based upon the foregoing and subject to the limitations and assumptions set
forth herein and having due regard for such legal considerations as we deem
relevant, we are of the opinion that the Shares have been duly and validly
authorized and when issued and paid for in accordance with the terms of the
Plans, will be validly issued, fully paid and nonassessable.

The foregoing opinion is based on and limited to the Wyoming Business
Corporation Act as reported in publicly available compilations and the relevant
law of the United States of America, and we render no opinion with respect to
any other law or the law of any other jurisdiction.  We hereby consent to the
filing of this opinion with the Commission as Exhibit 5 to the Registration
Statement.  By giving such consent, we do not admit that we are within the
category of persons
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whose consent is required under Section 7 of the Securities Act or the rules and
regulations of the Commission promulgated thereunder.

                              Very truly yours,
                              Bracewell & Patterson, L.L.P.