EXHIBIT 3.1

SIXTH AMENDED AND RESTATED  CERTIFICATE OF INCORPORATION    OF    BEACON POWER CORPORATION

The name of the Corporation is Beacon Power Corporation. The Corporation was originally incorporated on May 8, 1997 pursuant to Sections 242 and 245
of the General Corporation Law of the State of Delaware. This Sixth Amended and Restated Certificate of Incorporation of Beacon Power Corporation was proposed and declared advisable by the Board of
Directors of the Corporation on October 18, 2000 and was consented to in writing by the Corporation's stockholders as of October 18, 2000, in accordance with Sections 228, 242 and
245 of the General Corporation Law of the State of Delaware. The Corporation's Amended and Restated Certificate of Incorporation is hereby amended and restated in its entirety to read as follows:

FIRST:The name of the Corporation is Beacon Power Corporation.

SECOND:The address of its registered office in the State of Delaware is Corporation Trust Center, 1209 Orange Street, in the City
of Wilmington, County of New Castle. The name of its registered agent at such address is The Corporation Trust Company.

THIRD:The nature of the business or purposes to be conducted or promoted by the Corporation is as follows:



FOURTH:The total number of shares of all classes of stock which the Corporation shall have authority to issue is 110,000,000 shares of
common stock, $0.01 par value per share ("Common Stock") and 10,000,000 shares of preferred stock, $0.01 par value per share, ("Preferred Stock").

The
following is a statement of the designations and the powers, privileges and rights, and the qualifications, limitations or restrictions thereof in respect of each class of capital
stock of the Corporation.

A.COMMON STOCK.



B.PREFERRED STOCK.



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FIFTH:In furtherance of and not in limitation of powers conferred by statute, it is further provided:



SIXTH:Except to the extent that the General Corporation Law of Delaware prohibits the elimination or limitation of liability of directors
for breaches of fiduciary duty, no director of the Corporation shall be personally liable to the Corporation or its stockholders for monetary damages for any breach of fiduciary duty as a director,
notwithstanding any provision of law imposing such liability. No amendment to or repeal of this provision shall apply to or have any effect on the liability or alleged liability of any director of the
Corporation for or with respect to any acts or omissions of such director occurring prior to such amendment.

SEVENTH:The Corporation shall, to the fullest extent not prohibited by Section 145 of the General Corporation Law of Delaware, as
amended from time to time, indemnify each person who was or is a party or is threatened to be made a party to any threatened, pending or completed action, suit or proceeding, whether civil, criminal,
administrative or investigative, by reason of the fact that he is or was, or has agreed to become, a director or officer of the Corporation, or is or was serving, or has agreed to serve, at the
request of the Corporation, as a director, officer or trustee of, or in a similar capacity with, another corporation, partnership, joint venture, trust or other enterprise (including any employee
benefit plan) (all such persons being referred to hereafter as an "Indemnitee"), or by reason of any action alleged to have been taken or omitted in such capacity, against all expenses (including
attorneys' fees), judgments, fines and amounts paid in settlement actually and reasonably incurred by or on behalf of an Indemnitee in connection with such action, suit or proceeding and any appeal
therefrom.

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As
a condition precedent to his right to be indemnified, the Indemnitee must notify the Corporation in writing as soon as practicable of any action, suit proceeding or investigation
involving him for which indemnity will or could be sought. With respect to any action, suit, proceeding or investigation of which the Corporation is so notified, the Corporation will be entitled to
participate therein at its own expense and/or to assume the defense thereof at its own expense, with legal counsel reasonably acceptable to the Indemnitee.

In
the event that the Corporation does not assume the defense of any action, suit, proceeding or investigation of which the Corporation receives notice under this Article, the
Corporation shall pay in advance of the final disposition of such matter any expenses (including attorneys' fees) incurred by an indemnitee in defending a civil or criminal action, suit, proceeding or
investigation or any appeal therefrom;provided,however, that the payment of such expenses incurred by
an Indemnitee in advance of the final disposition of such matter shall be made only upon receipt of an undertaking by or on behalf of the Indemnitee to repay all amounts so advanced in the event that
it shall ultimately be determined that the Indemnitee is not entitled to be indemnified by the Corporation as authorized in this Article, which undertaking shall be accepted without reference to the
financial ability of the Indemnitee to make such repayment; andfurther providedthat no such advancement of expenses shall be made if it is determined
that the Indemnitee did not act in good faith and in a manner he reasonably believed to be in, or not opposed to, the best interests of the Corporation, and, with respect to any criminal action or
proceeding, had no reasonable cause to believe his conduct was unlawful.

If
a claim for indemnification or advancement of expenses hereunder is not paid in full by the Corporation within sixty (60) days after a written claim has been received by the
Corporation, the Indemnitee may at any time thereafter bring suit against the Corporation to recover the unpaid amount of the claim, and if successful in whole or in part, the Indemnitee shall be
entitled to be paid the expenses he incurrred in prosecuting such claim.

The
Corporation shall not indemnify an Indemnitee to the extent such Indemnitee is reimbursed from the proceeds of insurance, and in the event the Corporation makes any indemnification
payments to an Indemnitee and such Indemnitee is subsequently reimbursed from the proceeds of insurance, such Indemnitee shall promptly refund such indemnification payments to the Corporation to the
extent of such insurance reimbursement.

All
determinations hereunder as to the entitlement of an Indemnitee to indemnification or advancement of expenses shall be made in each instance by (a) a majority vote of the
directors of the Corporation consisting of persons who are not at that time parties to the action, suit or proceeding in question ("disinterested directors"), whether or not a quorum, (b) a
majority vote of a quorum of the outstanding shares of stock of all classes entitled to vote for directors, voting as a single class, which quorum shall consist of stockholders who are not at that
time parties to the action, suit or proceeding in question, (c) independent legal counsel (who may, to the extent permitted by law, be regular legal counsel to the Corporation), or (d) a
court of competent jurisdiction.

The
Indemnification rights provided in this Article (i) shall not be deemed exclusive of any other rights to which an Indemnitee may be entitled under any law, agreement or vote
of stockholders or disinterested directors or otherwise, and (ii) shall inure to the benefit of the heirs, executors and administrators of the Indemnitees. The Corporation may, to the extent
authorized from time to time by its Board of Directors, grant indemnification rights to other employees or agents of the Corporation or other persons serving the Corporation and such rights may be
equivalent to, or greater or less than, those set forth in this Article.

EIGHTH:Commencing with the 2001 annual meeting of stockholders of the Corporation, the directors of the Corporation shall be divided,
with respect to the time for which they severally hold office, into three classes, as nearly equal in number as possible, with the term of office of the first class to expire at the 2002 annual
meeting of the stockholders of the Corporation, the term of office of the

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second
class to expire at the 2003 annual meeting of the stockholders of the Corporation and the term of office of the third class to expire at the 2004 annual meeting of the stockholders of the
Corporation, with each director to hold office until his or her successor shall have been duly elected and qualified. At each annual meeting of stockholders of the Corporation, commencing with the
2002 annual meeting, directors elected to succeed those directors whose terms then expire shall be elected for a term of office to expire at the third succeeding annual meeting of stockholders of the
Corporation after their election.

NINTH:Subject to the approval rights of holders of Common Stock or Preferred Stock set forth in this Amended and Restated Certificate,
the Corporation reserves the right to amend, alter, change or repeal any provision contained in this Amended and Restated Certificate of Incorporation, in the manner now or hereafter prescribed by
statute and this Amended and Restated Certificate of Incorporation, and all rights conferred upon stockholders herein are granted subject to this reservation.

EXECUTED
at Woburn, Massachusetts, on November 17, 2000.

| | /s/MAUREEN LISTERMaureen Lister,Secretary
| | -----------------------------------------

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