UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13G

Under the Securities Exchange Act of 1934

(Amendment No. 2)*

Eos Energy Enterprises, Inc.

(Name of Issuer)

Common Stock, par value $0.0001 per share

(Title of Class of Securities)

29415C101

(CUSIP Number)

May 2, 2022

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

☐ Rule 13d-1(b)

☒ Rule 13d-1(c)

☐ Rule 13d-1(d)

The information required in the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

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On July 6, 2021, Spring Creek Capital, LLC (“Spring Creek”) entered into an investment agreement (the “Investment Agreement”) with the Issuer relating to the issuance and sale of $100,000,000 in aggregate principal amount of the Issuer’s 5%/6% Convertible Senior PIK Toggle Notes due 2026 (the “Notes”). The Notes were issued to Spring Creek on July 7, 2021. The Investment Agreement contemplated an ability to issue the Notes under an indenture to facilitate transferability. As permitted by the Investment Agreement, the Issuer reissued the Notes in an aggregate principal amount of $102,900,000, including $2,900,000 principal amount of the Notes representing interest previously paid in kind, pursuant to an indenture with Wilmington Trust, National Association, as trustee, dated as of April 7, 2022.

On May 2, 2022, Spring Creek transferred the Notes and 2,538,261 Public Shares to Wood River. No consideration was paid by Wood River to Spring Creek in connection with these transfers. The Notes are convertible into shares of the Issuer’s common stock at the holder’s option at any time until the business day prior to the maturity date, based on an initial conversion rate of 49.9910 shares per $1,000 principal amount of the Notes, subject to customary anti-dilution and other adjustments.

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CUSIP: 29415C101

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Item 1(a). Name of Issuer: Eos Energy Enterprises, Inc. (the “Issuer”)

Item 1(b). Address of Issuer’s Principal Executive Officers: 3920 Park Avenue, Edison, NJ 08820

Item 2(a). Name of Person Filing:

Wood River Capital, LLC (“Wood River”)

SCC Holdings, LLC (“SCC”)

KIM, LLC (“KIM”)

Koch Investments Group, LLC (“KIG”)

Koch Investments Group Holdings, LLC (“KIGH”)

Koch Industries, Inc. (“Koch Industries”)

(Each a “Reporting Person,” and collectively, the “Reporting Persons”).

Item 2(b). Address or Principal Business Office or, if None, Residence:

The principal business office for all Reporting Persons filing is:

4111 E. 37^th Street North

Wichita, KS 67220

Item 2(c). Citizenship: See Item 4 of each cover page.

Item 2(d).Title of Class of Securities: Common stock, par value $0.0001 per share (“Public Shares”).

Item 2(e).CUSIP No.: 29415C101.

Item 3. If this Statement is Filed Pursuant to §§ 240.13d-1(b) or 240.13d-2(b) or (c), Check Whether the Person Filing is a: Not applicable.

Item 4. Ownership.

(a) Amount beneficially owned: See Item 9 of each cover page.

(b) Percent of class: See Item 11 of each cover page. Calculated using 59,103,013 Public Shares deemed outstanding as of February 16, 2022, including 53,958,013 Public Shares outstanding as of February 16, 2022 as reported in the Form 10-K filed by the Issuer on February 25, 2022 and 5,145,000 Public Shares issuable upon conversion of the Notes.

(c) Number of shares as to which the person has:

Wood River is beneficially owned by SCC, SCC is beneficially owned by KIM, KIM is beneficially owned by KIG, KIG is beneficially owned by KIGH, and KIGH is beneficially owned by Koch Industries, in each case by means of ownership of all voting equity instruments.

Koch Industries, SCC, KIM, KIG, and KIGH may be deemed to beneficially own the Public Shares held by Wood River by virtue of (i) Koch Industries’ beneficial ownership of KIGH, (ii) KIGH’s beneficial ownership of KIG, (iii) KIG’s beneficial ownership of KIM, (iv) KIM’s beneficial ownership of SCC and (v) SCC’s beneficial ownership of Wood River. The filing of this Schedule 13G shall not be construed as an admission that any of SCC, KIM, KIG, KIGH, or Koch Industries is, for purposes of Sections 13(d) or 13(g) of the Exchange Act, the beneficial owner of any Public Shares covered by this Schedule 13G.

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Item 5. Ownership of 5 Percent or Less of a Class.

Not applicable.

Item 6. Ownership of More than 5 Percent on Behalf of Another Person.

Not applicable.

Item 7. Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.

Not applicable.

Item 8. Identification and Classification of Members of the Group.

Not applicable.

Item 9. Notice of Dissolution of Group.

Not applicable.

Item 10. Certifications.

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under §240.14a-11.

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After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

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EXHIBIT INDEX

EXHIBIT 99.1

JOINT FILING AGREEMENT

This will confirm the agreement by and among the undersigned that the Schedule 13G/A filed with the Securities and Exchange Commission on or about the date hereof with respect to the beneficial ownership by the undersigned of the shares of Common Stock, par value $0.0001 per share, of Eos Energy Enterprises, Inc. (this “Agreement”), is being filed, and all amendments thereto will be filed, on behalf of each of the persons and entities named below that is named as a reporting person in such filing in accordance with Rule 13d-1(k) under the Securities Exchange Act of 1934, as amended. This Agreement may be executed in two or more counterparts, each of which shall be deemed an original, but all of which together shall constitute one and the same instrument.