THIRD AMENDED AND RESTATED CONVERTIBLE PROMISSORY NOTE

THE SECURITY REPRESENTED BY THIS INSTRUMENT HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"). ACCORDINGLY, THIS SECURITY MAY NOT BE OFFERED OR SOLD EXCEPT PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER THE SECURITIES ACT OR PURSUANT TO AN AVAILABLE EXEMPTION FROM, OR IN A TRANSACTION NOT SUBJECT TO, THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT AND IN ACCORDANCE WITH APPLICABLE STATE SECURITIES LAWS, AS EVIDENCED BY A LEGAL OPINION OF COUNSEL TO THE TRANSFEROR TO SUCH EFFECT, THE SUBSTANCE OF WHICH SHALL BE REASONABLY ACCEPTABLE TO THE COMPANY. THIS SECURITY AND THE SECURITIES ISSUABLE UPON CONVERSION OF THIS SECURITY MAY BE PLEDGED IN CONNECTION WITH A BONA FIDE MARGIN ACCOUNT OR OTHER LOAN SECURED BY SUCH SECURITIES. THE TRANSFER OF THIS SECURITY IS ALSO SUBJECT TO THE CONDITIONS SPECIFIED IN THE NOTE PURCHASE AGREEMENT, DATED AS OF JANUARY 16, 2008, AS AMENDED AND MODIFIED FROM TIME TO TIME, BETWEEN QUANTUM FUEL SYSTEMS TECHNOLOGIES WORLDWIDE, INC. (THE "COMPANY") AND THE PURCHASER PARTY THERETO. THE COMPANY RESERVES THE RIGHT TO REFUSE THE TRANSFER OF SUCH SECURITY UNTIL SUCH CONDITIONS HAVE BEEN FULFILLED WITH RESPECT TO SUCH TRANSFER. UPON WRITTEN REQUEST, A COPY OF SUCH CONDITIONS SHALL BE FURNISHED BY THE COMPANY TO THE HOLDER HEREOF WITHOUT CHARGE.

THE SECURITIES REPRESENTED HEREBY ARE SUBJECT TO A CONVERTIBLE NOTE PURCHASE AGREEMENT, DATED AS OF JANUARY 16, 2008, BY AND BETWEEN THE COMPANY AND THE INVESTOR REFERRED TO THEREIN (THE "PURCHASE AGREEMENT"), AND THE HOLDER OF THE NOTE, BY ACCEPTANCE OF THIS NOTE, AGREES TO BE BOUND BY ALL APPLICABLE PROVISIONS OF THE PURCHASE AGREEMENT.

THIS NOTE AMENDS AND RESTATES THAT CERTAIN CONVERTIBLE PROMISSORY NOTE DATED JULY 10, 2009, IN THE ORIGINAL PRINCIPAL AMOUNT OF $7,171,441 (THE "JULY 10 NOTE"). THE JULY 10 NOTE AMENDED AND RESTATED THAT CERTAIN CONVERTIBLE PROMISSORY NOTE DATED JANUARY 16, 2008, IN THE ORIGINAL PRINCIPAL AMOUNT OF $16,195,676.30, AND THAT CERTAIN CONVERTIBLE PROMISSORY NOTE DATED MAY 30, 2008 (COLLECTIVELY WITH THE JULY 10 NOTE, THE "PRIOR NOTES"), ISSUED BY THE UNDERSIGNED TO THE ORDER OF WB QT, LLC. (THE "HOLDER"). IT IS EXPRESSLY INTENDED, UNDERSTOOD AND AGREED THAT THIS NOTE SHALL REPLACE THE PRIOR NOTES AS EVIDENCE OF SUCH INDEBTEDNESS OF THE UNDERSIGNED TO THE HOLDER, AND SUCH INDEBTEDNESS OF THE UNDERSIGNED TO THE HOLDER HERETOFORE REPRESENTED BY THE PRIOR NOTES, AS OF THE DATE HEREOF, SHALL, TO THE EXTENT NOT ALREADY PAID, BE CONSIDERED OUTSTANDING HEREUNDER FROM AND AFTER THE DATE HEREOF AND SHALL NOT BE CONSIDERED PAID (NOR SHALL THE UNDERSIGNED'S OBLIGATION TO PAY THE SAME BE CONSIDERED DISCHARGED OR SATISFIED) AS A RESULT OF THE ISSUANCE OF THIS NOTE. THE PRINCIPAL AMOUNT DUE UNDER THIS NOTE REFLECTS ANY PRINCIPAL REDUCTIONS RESULTING FROM HOLDER'S CONVERSIONS OF PRINCIPAL THAT OCCURRED BETWEEN JANUARY 16, 2008 AND THE DATE HEREOF.

QUANTUM FUEL SYSTEMS TECHNOLOGIES WORLDWIDE, INC.

THIRD AMENDED AND RESTATED
CONVERTIBLE PROMISSORY NOTE

QUANTUM FUEL SYSTEMS TECHNOLOGIES WORLDWIDE, INC., a Delaware corporation (the " Company "), hereby promises to pay to the order of WB QT, LLC, a Delaware limited liability company (the " Purchaser "), the principal amount of Seven Million One Hundred Seventy-One Thousand Four Hundred Forty-One Dollars ($7,171,441) plus the portion of the Accreted Principal Amount (as defined below) in excess thereof together with interest on the Accreted Principal Amount calculated from the date hereof in accordance with the provisions of this Note. The Prior Notes were issued pursuant to the Note Purchase Agreement, dated as of January 16, 2008 (the " Purchase Agreement "), between the Company and the Purchaser. The Purchase Agreement contains terms governing the rights of the holder of the Prior Notes and this amended Note (collectively, this " Note "), and all provisions of the Purchase Agreement are hereby incorporated herein in full by reference, provided that to the extent that the terms and conditions of this Note are different from or in addition to the terms and conditions of the Purchase Agreement, the Purchase Agreement shall be deemed amended hereby to conform to the terms and conditions of this Note. Unless otherwise indicated herein, capitalized terms used in this Note have the same meanings set forth in the Purchase Agreement.

ARTICLE I
PAYMENT OF INTEREST; CONTINGENT INTEREST

Interest shall accrue on the Accreted Principal Amount (in each case computed on the basis of a 365/366-day year and the actual number of days elapsed in any year) at an annual rate equal to 11.50% (or, from and after any extension of the maturity date of this Note under Section 2.1 below, 9.5%) per annum or (if less) at the highest rate then permitted under applicable law, all of which shall be payable by adding such interest to the Accreted Principal Amount on each Interest Payment Date (as defined below), and on the final maturity hereof (the " PIK Amounts "). At any time, the outstanding principal amount of this Note, including all PIK Amounts and Default PIK Amounts (as defined below) added thereto through such time, is referred to in this Note as the " Accreted Principal Amount ." All accrued interest (including PIK Amounts, Default PIK Amounts and interest on the Accreted Principal Amount) shall be added to the Accreted Principal Amount on the first day of each July and January (each, an " Interest Payment Date ") and on the final maturity date of this Note. Any Accreted Principal Amount (including PIK Amounts and Default PIK Amounts) which for any reason has not theretofore been paid shall increase the principal of the Note and be paid in full on the date on which the final principal payment on this Note is made (the " Default PIK Amounts "); provided , however , that any such reason shall not affect or waive any Event of Default that arises due to the failure to make such payment in cash; provided further , that the Company has the option to elect by written notice to Lender at least five (5) business days prior to each Interest Payment Date to pay a total of 6.5% of the PIK Amounts in cash. Interest shall accrue on any principal payment due under this Note (including as to accrued interest added to the principal) until such time as payment therefor is actually delivered to the holder of this Note.

ARTICLE II
PAYMENT OF PRINCIPAL ON NOTE

Section 2.1       Scheduled Payment . The Company shall pay the Accreted Principal Amount or, if less, the outstanding principal amount of this Note to the holder of this Note on August 31, 2010, together with all accrued and unpaid interest on the principal amount being repaid At the election of the Purchaser in its sole discretion and upon written notice to the Company no later than August 15, 2010, such maturity date shall be extended until August 31, 2013 (either such date, the " Maturity Date ").

Section 2.2       Conversion . Notwithstanding any provision contained in this Article 2, the holder of this Note may convert all or any portion of the outstanding principal amount of this Note into shares of common stock, $.001 par value per share, of the Company (the " Common Shares ") in accordance with Article 6 until such time as such principal amount has been paid.

ARTICLE III

[Reserved].

ARTICLE IV

[Reserved].

ARTICLE V
EVENTS OF DEFAULT; REMEDIES ON DEFAULT

Section 5.1       Event of Default . An " Event of Default " shall exist if any of the following conditions or events shall occur and be continuing:

1. 1. 1. the Company defaults in the payment of principal on the Note when the same becomes due and payable, whether at maturity or at a date fixed for prepayment or by declaration or otherwise, or fails to deliver the Common Shares to the Purchaser in the manner and at the times set forth in Article 6 hereof, and such failure to pay is not cured within three (3) business days after the occurrence thereof; or
      2. the Company defaults in the payment of any interest on the Note for more than five (5) business days after the same becomes due and payable; or
      3. the Company defaults with respect to Section 6.1 of the Purchase Agreement; or
      4. the Company defaults in the performance of, or compliance with, any other term contained in the Purchase Agreement or the Note (other than those referred to in Section 5.1(a), (b) or (c) above) and the default is not remedied within thirty (30) days after the earlier of (i) the Chief Executive Officer or the Chief Financial Officer obtaining actual knowledge of the default and (ii) the Company receiving written notice of the default from the holder of this Note (any such written notice to be identified as a "notice of default" and to refer specifically to this Section 5.1(d)); or
      5. any representation or warranty made by the Company in Article IV of the Purchase Agreement proves to have been false in any material respect on the Closing Date; or
      6. the Company (i) is generally not paying, or admits in writing its inability to pay its debts as they become due (ii) files, or consents by answer or otherwise to the filing against it of, a petition for relief or reorganization or arrangement or any other petition in bankruptcy, for liquidation or to take advantage of any bankruptcy, insolvency, reorganization, moratorium or other similar law of any jurisdiction, (iii) makes an assignment for the benefit of its creditors, (iv) consents to the appointment of a custodian, receiver, trustee or other officer with similar powers with respect to it or with respect to any substantial part of its property or (v) is adjudicated as insolvent or to be liquidated; or
      7. a court or Governmental Authority of competent jurisdiction enters an order appointing, without consent by the Company, a custodian, receiver, trustee or other officer with similar powers with respect to it or with respect to any substantial part of its property, or constituting an order for relief or approving a petition for relief or reorganization or any other petition in bankruptcy or for liquidation or to take advantage of any bankruptcy or insolvency law of any jurisdiction, or ordering the dissolution, winding-up or liquidation of the Company, or any such petition shall be filed against the Company and such petition shall not be dismissed within thirty (30) days; or
      8. an Event of Default (as defined in the Credit Agreement) shall have occurred and be continuing and shall not have been waived by the requisite holders of Indebtedness under the Credit Agreement or cured.

Section 5.2       Acceleration .

1. 1. 1. If an Event of Default with respect to the Company described in subsection (f) of Section 5.1 has occurred, the Note shall automatically become immediately due and payable.
      2. If any other Event of Default has occurred and is continuing, the holder of the Note may at any time at his, her or its option, by notice to the Company, declare the Note to be immediately due and payable.
      3. Upon the Note becoming due and payable under this Section 5.2, whether automatically or by declaration, the Note will forthwith mature and the entire unpaid principal amount of the Note, plus all accrued and unpaid interest thereon, shall all be immediately due and payable, in each and every case without presentment, demand, protest or further notice, all of which are hereby waived.

Section 5.3       Other Remedies . If any Event of Default has occurred and is continuing, and irrespective of whether the Note has become or has been declared immediately due and payable under Section 5.1, the holder of the Note may proceed to protect and enforce the rights of such holder by an action at law, suit in equity or other appropriate proceeding, whether for the specific performance of any agreement contained herein, or for an injunction against a violation of any of the terms hereof or thereof, or in aid of the exercise of any power granted hereby or thereby or by law or otherwise.

Section 5