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):  July 10, 2012

A123 Systems, Inc.

(Exact Name of Registrant as Specified in Charter)

Registrant’s telephone number, including area code:  617-778-5700

(Former Name or Former Address, if Changed Since Last Report)

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 (see General Instruction A.2. below):

o            Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o            Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o            Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o            Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 8.01                     Other Events

As previously discussed in its Current Report on Form 8-K filed with the Securities and Exchange Commission on July 6, 2012, A123 Systems, Inc. (the “Company”) entered into a placement agent agreement dated as of July 5, 2012 with Lazard Capital Markets LLC relating to a registered direct offering by the Company of an aggregate of 7,692,308 shares of the Company’s common stock and warrants to purchase additional shares of such common stock. The legal opinion letter of Latham & Watkins LLP regarding the validity of the common stock and warrants is filed as Exhibit 5.1 to this Current Report on Form 8-K.  The legal opinion letter is also filed with reference to, and is hereby incorporated by reference into, the Company’s registration statement on Form S-3, as amended (Reg. No. 333-173122).

Item 9.01                     Financial Statements and Exhibits

(d) Exhibits

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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.

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