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                                                            EXHIBIT 10.73

                            STOCK PURCHASE AGREEMENT


                This STOCK PURCHASE AGREEMENT (the "Agreement") is made and
entered into by and among Honda Motor Co., Ltd., a Japanese corporation
("Honda"), Energy Conversion Devices, Inc., a Delaware corporation ("ECD"), and
Ovonic Battery Company, Inc., a Delaware corporation ("Ovonic Battery").

                WHEREAS, agreement was reached in Tokyo, Japan on March 18,
1996 between Honda and ECD for ECD to sell and convey to Honda and Honda to
purchase from ECD, 100 shares of common stock, par value $.01 per share (the
"Ovonic Battery Common Stock"), of Ovonic Battery and this agreement was
confirmed in a letter dated March 29, 1996 from Honda to ECD.

                WHEREAS, simultaneously with the execution of the Agreement,
and in order to induce Honda to purchase such shares, ECD, Ovonic Battery and
Honda are entering into a Registration Rights Agreement (the "Registration
Rights Agreement") in the form of Exhibit A hereto, and Honda, Honda R&D Co.,
Ltd., ECD and Ovonic Battery are entering into a Testing and Cooperation
Agreement (the "Testing and Cooperation Agreement") in the form of Exhibit B
hereto (collectively, the "Ancillary Agreements").

                NOW, THEREFORE, in consideration of the mutual covenants and
agreements set forth in this Agreement, and for other good and valuable
consideration, the receipt and sufficiency of which is hereby acknowledged, the
parties hereto agree as follows:

                1.      Purchase and Sale of Shares.  On the terms and subject
to the conditions set forth in this Agreement, ECD hereby sells to Honda, and
Honda hereby purchases from ECD, 100 shares of Ovonic Battery Common Stock
(such 100 shares of Ovonic Battery Common Stock, together with any additional
shares of Ovonic Battery Common Stock issued or distributed in respect of such
shares by way of a dividend, stock split or otherwise or acquired by way of a
recapitalization or otherwise, are herein referred to as the "Shares") free and
clear of all liens, claims and encumbrances ("Liens").

                2.      Purchase Price.  The purchase price being paid by Honda
for the purchase of the Shares is U.S. $4.5 million.

                3.      Delivery of Shares.  Simultaneously with the execution
and delivery of this Agreement, ECD is delivering to Honda a stock certificate
or certificates evidencing the Shares.

                4.      Representations and Warranties With Respect to Ovonic
Battery.  ECD and Ovonic Battery jointly and severally represent and warrant to
Honda as follows:

                        (a)     Ovonic Battery is a corporation duly organized,
validly existing and in good standing under the laws of the jurisdiction of its
incorporation.  Ovonic Battery is qualified to do business as a foreign
corporation in each jurisdiction in which it is required to
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be qualified, except jurisdictions in which the failure to qualify, in the
aggregate, would not have a material adverse effect on the business,
operations, properties, prospects or condition (financial or otherwise) of
Ovonic Battery. Ovonic Battery has delivered to Honda complete copies of its
certificate of incorporation and by-laws as in effect on the date hereof.

        (b)     Ovonic Battery has all corporate power and authority necessary
to enable it to enter into this Agreement and the Ancillary Agreements to which
it is a party and to perform its obligations hereunder and thereunder. All
corporate actions necessary to authorize Ovonic Battery to enter into this
Agreement and the Ancillary Agreements to which it is a party and to perform
its obligations hereunder and thereunder have been taken. Each of this
Agreement and the Ancillary Agreement to which Ovonic Battery is a party has
been duly executed by Ovonic Battery and constitutes a valid and binding
agreement of Ovonic Battery, enforceable against Ovonic Battery in accordance
with its terms.

        (c)     The execution or delivery by Ovonic Battery of each of this
Agreement and the Ancillary Agreements to which Ovonic Battery of is a party
and the performance of its obligations hereunder and thereunder do not and will
not violate, result in a breach of, or constitute a default (or an event which,
with notice or lapse of time or both would constitute a default) under, the
certificate of incorporation or by-laws (or comparable documents) of Ovonic
Battery, any agreement or instrument to which Ovonic Battery is a party or by
which it is bound, any law, or any order, rule or regulation of any court or
governmental authority having jurisdiction over Ovonic Battery or any of its
properties.

        (d)     The only authorized stock of Ovonic Battery is 10,000 shares of
Ovonic Battery Common Stock. The Shares are being conveyed to Honda free and
clear of all Liens. Each of the Shares has been duly authorized and validly
issued and is fully paid and nonassessable. Other than the options to acquire
six percent (6%) of the outstanding shares (currently, 186 shares) of Ovonic
Battery Common Stock held by Stanford R. Ovshinsky, Ovonic Battery has not
issued any options, warrants or convertible or exchangeable securities, and is
not a party to any other agreements, which require, or upon the passage of
time, the payment of money or the occurrence of any other event may require,
Ovonic Battery to sell or issue any of its stock. ECD owns 3,000 shares of
Ovonic Battery Common Stock subject to a proxy in favor of Stanford R.
Ovshinsky, free and clear of all Liens, Sanoh Industrial Co. Ltd. owns 100
shares of Ovonic Battery Common Stock and there are no other shares of Ovonic
Battery Common Stock issued and outstanding. All of the outstanding shares of
Ovonic Battery Common stock have been duly authorized and validly issued and
are fully-paid and nonassessable.

        (e)     No governmental filings, authorizations, approvals or consents,
or other governmental action, are required to permit Ovonic Battery to perform
its obligations under this Agreement and the Ancillary Agreements to which
Ovonic Battery is a party.
 
        (f)     As of the date hereof, there are no corporations or other
entities of which Ovonic Battery owns directly or indirectly 50% or more of the
equity (each such corporation or other entity, for all purposes of this
Agreement, a "subsidiary" of Ovonic Battery).



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                (g)  The unaudited financial statements (including the footnotes
thereto) of Ovonic Battery at June 30, 1992, 1993, 1994 and 1995, and for the
one-year periods ended on those dates, and the unaudited financial statements
(including the footnotes thereto) of Ovonic Battery at December 31, 1995, and
for the six-month period ended on that date, copies of which are included in
Exhibit 4-G, were prepared in accordance with generally accepted accounting
principles applied on a consistent basis and present fairly the financial
condition, results of operations and changes in cash flows of Ovonic Battery at
the dates, and for the periods, to which they relate. Ovonic Battery does not
have any obligation or liability (contingent or otherwise) except (i) as
reflected in the financial statements (including the footnotes thereto) included
in Exhibit 4-G and (ii) for commitments and obligations made, or liabilities
incurred, in the ordinary course of its business consistent with past practice,
none of which is material, either individually or in the aggregate, to the
financial condition or results of operations of Ovonic Battery.

                (h)  Since December 31, 1995, (i) there has not been any
material adverse change in the financial condition or results of operations of
Ovonic Battery compared with the financial condition of Ovonic Battery at
December 31, 1995, or the results of operations of Ovonic Battery for the same
period of the prior year, (ii) Ovonic Battery has conducted its business in the
ordinary course and in the same manner in which it was conducted prior to
December 31, 1995, (iii) Ovonic Battery has not made any distributions,
dividends, loans or advances or otherwise repurchased any of its capital stock,
(iv) Ovonic Battery has not made any borrowings other than intercompany
borrowings in the ordinary course of business and consistent with past practice,
(v) there has not been any material adverse change, or any event of which any
officer of ECD or Ovonic Battery is aware which could reasonably be expected to
cause a material adverse change, in the business, operations, properties,
prospects or condition (financial or otherwise) of Ovonic Battery, (vi) Ovonic
Battery has not sold or otherwise disposed of any of its assets other than sales
of inventory or fixed assets which have come to the end of their useful life in
the ordinary course of business consistent with past practice, (vii) Ovonic
Battery has not acquired any assets, properties, capital stock or business of
any person except for inventory or equipment acquired in the ordinary course of
business, and (viii) Ovonic Battery has not merged or consolidated with any
other person or changed or agreed to rearrange in any manner the character of
its business. 

                (i)  Ovonic Battery has all material licenses and permits from
all governmental authorities which are necessary or useful to permit Ovonic
Battery to conduct its business as being conducted at the date of this
Agreement. Ovonic Battery is not in violation or default (and no event which,
with notice of lapse of time or both would constitute a default has occurred)
in any material respect under its certificate of incorporation or by-laws, any
agreement or instrument to which it is a party or by which it is bound, any
law, or any order, rule or regulation of any court or governmental authority
having jurisdiction over its properties. 

                (j)  Ovonic Battery owns all its assets free and clear of any
Liens other than (i) the lien of taxes not yet due or other statutory liens
relating to governmental obligations which are not yet due and (ii) liens
described in the ECD Reports (as hereinafter defined). The 


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assets of Ovonic Battery are sufficient to enable it to operate its business
after the date hereof substantially as it is being conducted on the date of
this Agreement.

                (k)     All Tax Returns (as defined below) required to be filed
with respect to Ovonic Battery have been timely filed. All Taxes (as defined
below) required to be shown on such Tax Returns or otherwise due have been
timely paid. No adjustments to such Tax Returns have been proposed. For the
purposes of this Agreement, the term "Taxes" means all taxes (including, but
not limited to, withholding taxes), assessments, fees, levies and other
governmental charges, and any related interest or penalties. For the purposes
of this Agreement, the term "Tax Return" means any report, return or other
information required to be supplied to a taxing authority in connection with
Taxes.

                (l)     Ovonic Battery is not a party to any suit or proceeding
in any court, or by or before any governmental authority, nor has any officer
of ECD or Ovonic Battery been notified that any suit or proceeding is
threatened against any Ovonic Battery other than (x) suits or proceedings in
which the other party seeks only money damages of less than $10,000 in each
instance and less than $50,000 as to all excluded suits and proceedings, (y)
suits or proceedings disclosed in the ECD Reports or (z) the MBI Litigations
(as defined in the Testing and Cooperation Agreement).

                (m)     Ovonic Battery has complied in all material respects
with all the requirements of the Employee Retirement Income Security Act of
1974, as amended ("ERISA") and of the Internal Revenue Code of 1986 as amended
(the "Code"), with regard to each of the employee benefit plans under which it
is providing compensation or benefits to any of its employees or is otherwise
considered an employer for purposes of ERISA or the Code. Each such plan that
is subject to Title IV of ERISA has no "amount of unfunded benefit liabilities"
(as defined in ERISA) as of the end of its most recently completed plan year and
the date hereof. Ovonic Battery does not have or expect to have any liability
under Title IV of ERISA, or have or expect to have any of its property subject
to a lien under ERISA or Section 401(a)(29) of the Code.

                (n)     Ovonic Battery has not received any notice of material
noncompliance or material liability under any Federal, state or local
environmental laws or regulations relating to real property owned or leased by
Ovonic Battery.

                (o)     Except as described in Exhibit 4-G and the ECD Reports,
Ovonic Battery does not have any indebtedness to any of its Affiliates (as
hereinafter defined) and none of such persons has any indebtedness to or other
claims against, contractual commitments to or otherwise provides property or
services to, Ovonic Battery and none of such indebtedness, claims, commitments
or property or services has existed or been provided since the December 31,
1995 except on terms no less favorable than could be obtained from an
unaffiliated third party on an arms' length basis. For purposes of this
Agreement, "Affiliate" shall mean any person directly or indirectly
controlling, controlled by or under direct or indirect common control with ECD
or Ovonic Battery and shall include (a) a director or beneficial holder of at
least 10% of the then outstanding capital stock of ECD or Ovonic Battery and
family members

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of any such person, (b) any person of which ECD or Ovonic Battery (or other
specified person) or an Affiliate (as defined in clause (a) above) of ECD or
Ovonic Battery (or other specified person) shall, directly or indirectly,
either beneficially own at least 10% of the then outstanding equity securities
or constitute at least a 10% equity participant, and (c) in the case of a
specified person who is an individual, family members of such person.

                (p)     No representation or warranty made by ECD and Ovonic
Battery in this Section 4 contains any untrue statement of a material fact, or
omits to state a material fact necessary to make the statements contained
therein not misleading in light of the circumstances in which made.

        5.      Representations and Warranties as to ECD. ECD and Ovonic
Battery jointly and severally represent and warrant to Honda as follows:

                (a)     ECD and each of its subsidiaries is a corporation or
other entity duly organized, validly existing and in good standing under the
laws of the jurisdiction of its incorporation or formation, as the case may be.
ECD and each of its subsidiaries is qualified to do business as a foreign
corporation or other entity in each jurisdiction in which it is required to be
qualified, except jurisdictions in which the failure to qualify, in the
aggregate, would not have a material adverse effect on the business,
operations, properties, prospects or condition (financial or otherwise) of ECD
and its subsidiaries, taken as a whole. ECD has delivered to Honda complete
copies of its certificate of incorporation and by-laws as in effect on the date 
hereof.

                (b)     ECD has all corporate power and authority necessary to
enable it to enter into this Agreement and the Ancillary Agreements and to
perform its obligations hereunder and thereunder. All corporate actions
necessary to authorize ECD to enter into this Agreement and the Ancillary
Agreements and to perform its obligations hereunder and thereunder have been
taken. Each of this Agreement and the Ancillary Agreements has been duly
executed by ECD and constitutes a valid and binding agreement of ECD,
enforceable against ECD in accordance with its terms.

                (c)     The execution or delivery of this Agreement and the
Ancillary Agreements by ECD and the performance of its obligations hereunder
and thereunder will not violate, result in a breach of, or constitute a default
(or an event which, with notice or lapse of time or both would constitute a
default) under, the certificate of incorporation or by-laws (or comparable
documents) of ECD or any of its subsidiaries, any agreement or instrument to
which ECD or any of its subsidiaries is a party or by which any of them is
bound, any law, or any order, rule or regulation of any court or governmental
authority having jurisdiction over ECD or any of its subsidiaries or any of its
or their properties.

                (d)     No governmental filings, authorizations, approvals, or
consents, or other governmental action, are required to permit ECD to perform
its obligations under this Agreement and the Ancillary Agreements.


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                (e)     Each of ECD's Annual Reports on Form 10-K for fiscal
years June 30, 1993, 1994 and 1995, and Quarterly Reports on Form 10-Q for the
periods ended September 30, 1995 and December 31, 1995 (collectively, the "ECD
Reports"), including the documents incorporated by reference in each of the ECD
Reports, contains all the information required to be included in it and does
not contain any untrue statement of a material fact or omit to state a material
fact necessary in order to make the statements made therein, in light of the
circumstances under which they were made, not misleading. The consolidated
financial statements included in the ECD Reports were prepared in accordance
with generally accepted accounting principles ("GAAP"), consistently applied,
and present fairly the consolidated financial position, consolidated results of
operations and changes in stockholders' equity and cash flows of ECD and its
subsidiaries at the dates, and for the periods, to which they relate. Since
December 31, 1995, ECD has made all disclosures about its activities and
financial condition required by the Securities Exchange Act of 1934, as amended
(the "Exchange Act"), and the rules under the Exchange Act. Since December 31,
1995 there has not been any material adverse change, or any event of which any
officer of ECD, Ovonic Battery or any of its subsidiaries is aware which could
reasonably be expected to cause a material adverse change, in the business,
operations, properties, prospects or condition (financial or otherwise) of ECD
and its subsidiaries, taken as a whole.

        6.      Representations and Warranties of Honda. Honda represents and
warrants to each of Ovonic Battery and ECD as follows:

                (a)     Honda is a corporation duly organized, validly existing
and in good standing under the laws of Japan.

                (b)     Honda has all corporate power and authority necessary
to enable it to enter into this Agreement and the Ancillary Agreements and to
perform its obligations hereunder and thereunder. All corporate actions
necessary to authorize Honda to enter into this Agreement and the Ancillary
Agreements and to perform its obligations hereunder and thereunder have been
taken. This Agreement and the Ancillary Agreements have been duly executed by
Honda and are valid and binding agreements of Honda, enforceable against Honda
in accordance with their terms.

                (c)     The execution and delivery of this Agreement or of the
Ancillary Agreements and the consummation of the transactions contemplated by
this Agreement or the Ancillary Agreements will not violate, result in a breach
of, or constitute a default (or an event which, with notice or lapse of time or
both, would constitute a default) under, the articles of incorporation or
regulations of Honda, any agreement or instrument to which Honda is a party or
by which it is bound, any law, or any order, rule or regulation of any court or
governmental authority having jurisdiction over Honda or any of its properties.

                (d)     No governmental filings, authorizations, approvals or
consents, or other governmental action, are required to permit Honda to perform
its obligations under this Agreement and the Ancillary Agreements, except for
the notification required under the Japanese Foreign Exchange Control Law.

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                (e)     Honda is an "accredited investor," as that term is
defined in Regulation D of the Securities Act of 1933, as amended. Honda is
acquiring the Shares for its own account for the purpose of investment and not
with a view to the resale or distribution thereof, and Honda has no present
intention of selling, negotiating or otherwise disposing of the Shares, except
as otherwise provided in this Agreement. It has been provided with all
information regarding Ovonic Battery it deems necessary in connection with its
decision to purchase the Shares. It has such knowledge and experience in
business and financial matters so as to enable it to evaluate the risks and
merits of an investment in the Shares.

        7.      Covenants of Ovonic Battery and ECD. ECD and Ovonic Battery
jointly and severally covenant that:

                (a)     None of Ovonic Battery or any of its subsidiaries
shall, without the prior consent of the holders of a majority of the Shares,
engage in any transactions with any of its Affiliates on terms less favorable
than those that would be available from an unaffiliated third party on an
arm's-length basis.

                (b)     Upon the request of Honda, and for so long as Honda and
its affiliates shall own not less than fifty percent (50%) of the Shares, Honda
may nominate a representative of Honda to serve as a director on Ovonic
Battery's Board of Directors and ECD shall vote all its shares of Ovonic
Battery Common Stock in favor of the election of such Honda representative and
ECD and Ovonic Battery shall take any other actions reasonably required to
cause such election to occur.

                (c)     Ovonic Battery will deliver to the holders of the 
Shares:

                        (i)     As soon as practicable, and in any event within
50 days after the closing of each of the first three quarterly periods of
Ovonic Battery in each fiscal year, (a) a consolidated balance sheet of Ovonic
Battery and its subsidiaries as of the end of such period, and (b) consolidated
statements of operations and changes in stockholders equity and cash flows of
Ovonic Battery and its subsidiaries for such period, and certified by the
principal financial officer of Ovonic Battery as having been prepared in
accordance with GAAP applied consistently throughout the periods reflected
therein (except as otherwise disclosed in reasonable detail therein);

                        (ii)    As soon as practicable, and in any event within
105 days after the close of each fiscal year of Ovonic Battery (a) a
consolidated balance sheet of Ovonic Battery and its subsidiaries as of the end
of such fiscal year, and (b) consolidated statements of operations and changes
in stockholders equity and cash flows of Ovonic Battery and its subsidiaries
for such fiscal year, all of the foregoing to be prepared in accordance with
GAAP and certified by the principal financial officer of Ovonic Battery as
having been prepared in accordance with GAAP applied consistently throughout
the periods reflected therein (except as otherwise disclosed in reasonable
detail therein);

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                                (iii)   Such other information, reports,
statements and information as such holders may from time to time reasonably
request.

                        (d)     Ovonic Battery will not, without the prior
written consent of the holders of a majority of the Shares, make any change in
its authorized capital stock or otherwise amend its certificate of
incorporation or by-laws so as to impair, prejudice or otherwise adversely
affect any right, privilege or benefit to which the holders of the Shares are
entitled.

                        (e)     Should Honda wish to sell the Shares, ECD and
Ovonic Battery agree to assist Honda in placing the Shares.  In addition, Ovonic
Battery and ECD agree to negotiate in good faith with Honda to exchange such
Shares (i) if Honda so requests, for credit on upfront fees for new business
transactions from time to time between Honda and any of its affiliates with
either ECD or Ovonic Battery until such time as the credit equals Honda's
entire $4.5 million payment for the Shares (it being agreed Honda may use part
of the Shares for partial credits), (ii) if Honda so requests, for a 5% share
of actual cash royalties received by Ovonic Battery after the exchange (which
may only be made with respect to all of the Shares) until such time as Honda
recoups its entire $4.5 million payment for the Shares or (iii) for any
combination of clause (i) or clause (ii) above mutually agreeable to Honda,
Ovonic Battery and ECD.

                8.      Restrictions on Transfer; Right of First Refusal.

                        (a)     Except as provided in Paragraph 8(b), until
Ovonic Battery becomes a reporting company pursuant to Section 13 or 15 of the
Exchange Act, Honda shall not sell, assign, transfer, encumber or otherwise
dispose of any Shares to any person unless:

                                (i)     Honda shall have received a bona fide
offer in writing from an unaffiliated third party (a "Bona Fide Offer"), which
Bona Fide Offer shall provide for the purchase of the Shares in exchange for
cash and Honda shall have first given written notice (the "Transfer Notice") to
ECD stating Honda's intention to transfer all or a portion of the Shares
pursuant to the Bona Fide Offer, the number of shares that Honda proposes to
transfer, the name and address of the proposed transferee and the offered
purchase price per share of the Shares to be transferred and the manner of
payment therefor.  The Transfer Notice shall be accompanied by a copy of the
Bona fide Offer.

                                (ii)    Upon the giving of a Transfer Notice,
ECD shall have the irrevocable and exclusive option, but not the obligation, to
purchase all (but not less than all) of the Shares to be transferred.  Such
option shall be exercised by so notifying Honda within 20 days of the delivery
of the Transfer Notice.  Failure by ECD to deliver the notice required by this
Paragraph 8(a)(ii) shall be deemed an election not to purchase the Shares
proposed to be sold.

                                (iii)   In the event that ECD shall fail to
give a notice provided for in Paragraph 8(a)(ii) or ECD shall elect to purchase
less than all of the Shares to be transferred, the election, if any, made
pursuant to said Paragraph shall be null and void and shall have no


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force and effect; whereupon Honda may accept the Bona Fide Offer and effect the
proposed transfer with respect to said Shares on the terms of such Bona Fide
Offer within a period of 60 days following the delivery of the Transfer Notice
(the "Third Party Closing Date"). If the proposed transfer is not completed on
or before the Third Party Closing Date, then the Bona Fide Offer shall be
deemed withdrawn and no Transfer shall be effected except pursuant to a new
Bona Fide Offer and otherwise in accordance with this Paragraph 8.  

                (iv)  Unless Honda and ECD otherwise agree, if the Shares to be
transferred are purchased by ECD pursuant to this Paragraph 8, then such
purchase shall be completed (the "Paragraph 8 Closing") at the principal
executive offices of Ovonic Battery, at 10:00 A.M. local time on the date 120
days following the delivery of the Transfer Notice (the "Paragraph 8 Closing
Date"). Any Shares purchased by ECD pursuant to this Paragraph 8 shall be
purchased at a purchase price per share equal to the purchase price per share
set forth in the Bona Fide Offer and ECD shall pay the purchase price in the
manner set forth in the Bona Fide Offer as disclosed in the Transfer Notice. At
the Paragraph 8 Closing, Honda shall deliver, duly endorsed for transfer with
all required stock transfer tax stamps affixed thereto, certificates for all of
the Shares being purchased and sold at such Paragraph 8 Closing.

                (b)  Notwithstanding anything contained in this Paragraph 8 to
the contrary, Honda may sell, assign, transfer or otherwise dispose of the
Shares (i) to any of its affiliates (provided that such affiliate agrees to be
bound by the provisions of this Paragraph 8), (ii) to ECD or Ovonic Battery as
described in Paragraph 7(e) or (iii) in connection with any public offering of
equity securities by Ovonic Battery pursuant to the Registration Rights
Agreement. 

                (c)  Any Shares sold by Honda pursuant to a Bona Fide Offer
shall not be subject to the transfer restrictions and right of first refusal
described in this Paragraph 8 after the date of such sale. 

                (d)  The certificates for the Shares shall be stamped or
otherwise imprinted with a legend in substantially the following form until
such time as the securities law restrictions set forth therein shall no longer
be applicable: 

        The shares evidenced by this certificate have not been registered under
        the Securities Act of 1933 (the "Act"), as amended, and may not be sold
        or transferred in the absence of such registration or an exemption
        therefrom under the Act. 

                (e)  Until (i) Ovonic Battery becomes a reporting company
pursuant to Section 13 or 15 of the Exchange Act or (ii) with respect to any
Shares, such Shares are sold by Honda pursuant to a Bona Fide Offer, the
certificates for the Shares shall be stamped or otherwise imprinted with a
legend in substantially the following form: 

        The shares evidenced by this certificate are subject to certain transfer
        restrictions set forth in a Stock Purchase Agreement by and 



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                among Honda Motor Co., Ltd., Energy Conversion Devices, Inc., 
                and Ovonic Battery Company, Inc.

                9.      Tag Along.  Until Ovonic Battery becomes a reporting
company pursuant to Section 13 or 15 of the Exchange Act, ECD shall not
voluntarily sell, assign, transfer or otherwise dispose of any shares of Ovonic
Common Stock owned by ECD to any third party, if as a result thereof ECD would
own less than a majority of the outstanding shares of Ovonic Battery Common
Stock, unless such transfer is made in accordance with the following
provisions:

                        (a)     The proposed transfer must be made pursuant to
a bona fide offer in writing from an unaffiliated third party (an "ECD Offer").
In addition, ECD must afford each holder of the Shares the opportunity to sell,
in the same transaction contemplated by the ECD Offer, at the same price and on
the same terms, a number of Shares not less than the product of (x) the
quotient of the number of Shares held by such holder divided by the total
number of shares of Ovonic Battery Common Stock then held by ECD and all
holders of the Shares multiplied by (y) the number of shares of Ovonic Common
Stock to be sold by ECD pursuant to such ECD Offer. ECD will not consummate
such transaction if the prospective transferee(s) declines to allow the
participation of the holders of the Shares as contemplated above.

                        (b)     Each holder of the Shares shall, within 20 days
of the date of delivery of ECD's notice pursuant to subparagraph (a), notify
ECD of its election to sell its Shares pursuant to Paragraph 9(a). The failure
by any holder to deliver a notice pursuant to this Paragraph 9(b) shall be
deemed an election by such holder not to sell the Shares owned by such holder.

                10.     Preemptive Rights.  At any time that Shares shall be
issued and outstanding, and until Ovonic Battery becomes a reporting company
pursuant to Section 13 or 15 of the Exchange Act, Ovonic Battery shall not issue
any shares of its capital stock or any securities convertible into or
exchangeable for shares of its capital stock, or enter into any agreement in
respect of the offering, sale or issuance of shares of its capital stock or
such convertible or exchangeable securities, other than: (A) if such offering,
sale or issuance is in connection with a transaction pursuant to which Ovonic
Battery offers to each holder of the Shares the right to participate
proportionately according to its Pro Rata Share (as hereinafter defined) as of
the date of such proposed offering, sale or issuance and on the same terms and
conditions (any such offered shares or convertible or exchangeable securities
are collectively referred to as "Offered Securities"); (B) at any time in
connection with the offering, sale or issuance of any capital stock of Ovonic
Battery under a registration statement as provided for in the Registration
Rights Agreement; or (C) issuances of Ovonic Common Stock pursuant to the
exercise of the options now held by Mr. Ovshinsky as described in Paragraph
4(d). Any right granted pursuant to clause (A) of the preceding sentence shall
be exercisable by written notice to Ovonic Battery ("Acceptance Notices") given
within 30 days (the "Acceptance Period") after receipt by the holders of the
Shares of written notice of such proposed offering, sale or issuance (the
"Issuance Notice"). If any holder of Shares shall fail to respond to Ovonic
Battery within the Acceptance Period, such failure shall be deemed to be a
rejection of such holder's right to 



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<PAGE>   11
participate in the purchase of the securities to be issued; provided, however,
that the failure by any holder to participate in such offering, sale or
issuance with respect to one offering, sale or issuance of Offered Securities
shall not affect such holder's rights to participate in any subsequent offering
sale or issuance.  "Pro Rata Share" shall mean, as of any date, the ratio of
the number of Shares then held by each holder thereof to the total number of
shares of Ovonic Common Stock then outstanding.

                11.     Indemnification.

                        (a)     ECD and Ovonic Battery shall jointly and
severally indemnify Honda and its officers, directors, employees, agents,
affiliates, successors and assigns in respect of, and hold each of them
harmless from and against, any and all damages, fines, fees, penalties,
deficiencies, losses and expenses (including, without limitation, interest,
court costs, reasonable fees of attorneys, accountants and other experts or
other reasonable expenses of litigation or other proceedings or of any claim,
default or assessment)("Losses") suffered, incurred or sustained by any of them
or to which any of them becomes subject, resulting from, arising out of or
relating to any inaccuracy or breach of any representation or warranty or
failure to perform any covenant or agreement on the part of ECD or Ovonic
Battery contained in this Agreement, any Ancillary Agreement or any documents
delivered pursuant hereto or thereto.

                (b)             Honda shall indemnify ECD and Ovonic Battery
and their respective officers, directors, employees, agents, affiliates,
successors and assigns in respect of, and hold each of them harmless from and
against, any and all Losses suffered, incurred or sustained by any of them or
to which any of them becomes subject, resulting from, arising out of or
relating to any inaccuracy or breach of any representation or warranty or
failure to perform any covenant or agreement on the part of Honda contained in
this Agreement, any Ancillary Agreement or any documents delivered pursuant
hereto or thereto.

                12.     Miscellaneous.

                        (a)     Honda, Ovonic Battery and ECD will each pay its
own expenses in connection with the transactions which are the subject of this
Agreement, including legal fees.

                        (b)     Honda, Ovonic Battery and ECD will consult with
each other before issuing any press releases or otherwise making any public
statements with respect to this Agreement, except that nothing in this
Paragraph will prevent any party from making any statement when and as required
by law or by the rules of any securities exchange or securities trading system
on which securities of that party or an affiliate are traded.

                        (c)     This Agreement contains the entire agreement
among Honda, Ovonic Battery and ECD relating to the transactions which are the
subject of this Agreement, all prior negotiations, understandings and
agreements among Honda, Ovonic Battery and ECD are superseded by this
Agreement, and there are no representations, warranties, understandings or
agreements concerning the transactions which are the subject of this Agreement
other than those expressly set forth in this Agreement.


                                       11
<PAGE>   12
                (d)  All covenants, agreements, representations and warranties
made by the parties herein or pursuant hereto shall survive the consummation of
the transactions contemplated hereby. 

                (e)  The captions of the articles and paragraphs of this
Agreement are for reference only, and do not affect the meaning or
interpretation of this Agreement. 

                (f)  Neither this Agreement nor any right of any party under it
may be assigned by any other party without the prior consent of the other
parties hereto; except that Honda may assign its rights under this Agreement
(other than Section 7(c)) to any person who acquires Shares without violation
of this Agreement. 

                (g)  Any notice or other communication under this Agreement
must be in writing and will be deemed given when delivered in person or sent by
facsimile (with proof of receipt at the number to which it is required to be
sent), or on the third business day after the day on which mailed by Federal
Express or similar express delivery service from within the United States of
America (in the case of ECD and Ovonic Battery) or Japan (in the case of
Honda), to the following addresses (or such other address as may be specified
after the date of this Agreement by the party to which the notice or
communication is sent): 

        If to ECD and Ovonic Battery:

                Energy Conversion Devices, Inc.
                1675 West Maple Road
                Troy, Michigan 48084
                Attn: Stanford R. Ovshinsky
                      President
                Facsimile No.: 810-280-1456

                Ovonic Battery Company, Inc.
                1707 Northwood Drive
                Troy, Michigan 48084
                Attn: Subhash K. Dhar
                      President
                Facsimile No.: 810-280-0332

        If to Honda:

                Honda Motor Co., Ltd.
                No. 1-1.2-Chome
                Minamigoyama
                Minato-ku, Tokyo 107, Japan
                Attn: Hiroyuki Yoshino
                      Executive Vice President
                Facsimile No.: 011-81-4-8462-5080



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        (h)     This Agreement will be governed by, and construed under, the
laws of the State of Michigan relating to contracts made and to be performed in
that state.

        (i)     This Agreement may be amended only by a document in writing
signed each party hereto.

        (j)     This Agreement may be executed in two or more counterparts,
each of which will be deemed an original, but all of which together will
constitute one and the same agreement.


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<PAGE>   14
        IN WITNESS WHEREOF, Honda, Ovonic Battery and ECD have executed this
Agreement, intending to be legally bound by it, as of the 14th day of May, 1996.


                              HONDA MOTOR CO., LTD.



                              By: H. Yoshino
                                 ------------------------------------
                                  Name: Hiroyuki Yoshino
                                  Title: Executive Vice President

                              ENERGY CONVERSION DEVICES, INC.



                              By: Stanford R. Ovshinsky
                                 -------------------------------------
                                  Name: Stanford R. Ovshinsky
                                  Title: President & Chief Executive Officer

                              OVONIC BATTERY COMPANY, INC.



                              By: Robert C. Stempel
                                 -------------------------------------
                                  Name: Robert C. Stempel
                                  Title: Chairman