[SCHEDULE 13D/A] Solid Power, Inc. SEC Filing

Rhea-AI Filing Summary

Amendment No. 2 to a Schedule 13D for Solid Power, Inc. (Common Stock) reports changes in beneficial ownership by reporting persons David M. Leuschen and Pierre F. Lapeyre, Jr. as of September 23, 2025. The filing states that on September 19, 2025, REL and REL US sold a combined 7,235,803 shares in the open market at $3.58 per share. REL originally received 4,798,303 shares in the business combination and purchased 2,000,000 shares at $10.00 per share in a PIPE. As of the filing, Mr. Leuschen beneficially owns 6,704,303 shares (3.62%) and Mr. Lapeyre beneficially owns 9,010,694 shares (4.81%). The filing notes that on September 19, 2025, both reporting persons ceased to beneficially own more than 5% of the Common Stock.

Positive

• REL acquired 4,798,303 shares in the business combination, showing prior strategic investment alignment
• REL purchased 2,000,000 shares in a PIPE at $10.00, evidencing prior committed capital to the issuer
• Detailed ownership and warrant breakdowns are provided, including presently exercisable warrants used in percentage calculations

Negative

• REL and REL US sold 7,235,803 shares at $3.58 per share on September 19, 2025, a large open-market disposition
• Reporting persons' beneficial ownership dropped below 5%, reducing their disclosure threshold and potentially their perceived control
• Recent sale price ($3.58) is materially lower than PIPE purchase price ($10.00), indicating a wide gap between prior private investment pricing and public sale price

Insights

Financial Analyst

TL;DR: Significant open-market sales reduced reporting persons' stakes; ownership now below 5%, with prior PIPE purchases at $10 noted.

The disclosure shows material disposition activity: REL and REL US sold 7,235,803 shares at $3.58 each, which materially reduced the reporting persons' beneficial ownership percentages. Prior capital injections included a PIPE purchase of 2,000,000 shares at $10.00 and issuance of shares in the business combination. The updated beneficial ownership figures—3.62% for Mr. Leuschen and 4.81% for Mr. Lapeyre—use share counts that include presently exercisable warrants. For investors, the key facts are the timing, sale size, and the contrast between the PIPE price and the recent open-market sale price, which reflect changes in liquidity and ownership concentration.

Corporate Governance Expert

TL;DR: Reporting persons reduced stakes below 5%, changing disclosure status and potential governance influence.

The filing documents that Messrs. Leuschen and Lapeyre no longer exceed the 5% beneficial ownership threshold as of September 19, 2025, triggering an amendment to Schedule 13D. It details record holdings, shared voting/dispositive power through Sponsor and related entities, and the disposition event (aggregate 7,235,803 shares sold). The filing includes customary disclaimers of beneficial ownership for Sponsor-held shares. This change alters public disclosure obligations and may affect perceived voting influence, but the filing does not indicate any change to governance rights beyond adjusted beneficial ownership percentages.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

(Amendment No. 2)

SOLID POWER, INC.

(Name of Issuer)

Common Stock, par value $0.0001

(Title of Class of Securities)

83422N105

(CUSIP Number)

Christina Shalhoub
c/o Riverstone Holdings LLC, 712 Fifth Avenue, 36th Floor
New York, NY, 10019
212-993-0076

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

09/19/2025

(Date of Event Which Requires Filing of This Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§ 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box.

The information required on 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).

SCHEDULE 13D

CUSIP No. 83422N105

1

Name of reporting person

David M. Leuschen

2

Check the appropriate box if a member of a Group (See Instructions)

(a)
(b)

3

SEC use only

4

Source of funds (See Instructions)

OO

5

Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)

6

Citizenship or place of organization

UNITED STATES

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 1,745,546.00
8	Shared Voting Power 4,958,757.00
9	Sole Dispositive Power 1,745,546.00
10	Shared Dispositive Power 4,958,757.00

11

Aggregate amount beneficially owned by each reporting person

6,704,303.00

12

Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)

13

Percent of class represented by amount in Row (11)

3.62 %

14

Type of Reporting Person (See Instructions)

IN

Comment for Type of Reporting Person:

The amounts in Rows (8), (10) and (11) include 4,006,860 shares of the Issuer's Common Stock which may be purchased by exercising warrants that are presently exercisable. The percentage in Row (13) is based on 185,291,240 shares of the Issuer's Common Stock, which includes (i) 181,284,380 shares of the Issuer's Common Stock, as reported in the Issuer's Quarterly Report on Form 10-Q filed with the SEC on August 7, 2025, and (ii) 4,006,860 shares of the Issuer's Common Stock which may be purchased by exercising warrants that are presently exercisable.

SCHEDULE 13D

CUSIP No. 83422N105

1

Name of reporting person

Pierre F. Lapeyre, Jr.

2

Check the appropriate box if a member of a Group (See Instructions)

(a)
(b)

3

SEC use only

4

Source of funds (See Instructions)

OO

5

Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)

6

Citizenship or place of organization

UNITED STATES

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 4,051,937.00
8	Shared Voting Power 4,958,757.00
9	Sole Dispositive Power 4,051,937.00
10	Shared Dispositive Power 4,958,757.00

11

Aggregate amount beneficially owned by each reporting person

9,010,694.00

12

Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)

13

Percent of class represented by amount in Row (11)

4.81 %

14

Type of Reporting Person (See Instructions)

IN

Comment for Type of Reporting Person:

The amounts in Rows (7), (9) and (11) include 2,044,171 shares of the Issuer's Common Stock which may be purchased by exercising warrants that are presently exercisable. The amounts in Rows (8) and (10) include 4,006,860 shares of the Issuer's Common Stock which may be purchased by exercising warrants that are presently exercisable. The percentage in Row (13) is based on 187,335,411 shares of the Issuer's Common Stock, which includes (i) 181,284,380 shares of the Issuer's Common Stock, as reported in the Issuer's Quarterly Report on Form 10-Q filed with the SEC on August 7, 2025, and (ii) 6,051,031 shares of the Issuer's Common Stock which may be purchased by exercising warrants that are presently exercisable.

SCHEDULE 13D

Item 1.	Security and Issuer
(a)	Title of Class of Securities: Common Stock, par value $0.0001
(b)	Name of Issuer: SOLID POWER, INC.
(c)	Address of Issuer's Principal Executive Offices: 486 S. PIERCE AVE., SUITE E, Louisville, COLORADO , 80027.
Item 1 Comment: This Amendment No. 2 to Schedule 13D (this "Amendment No. 2") amends and supplements the Schedule 13D originally filed with the United States Securities and Exchange Commission (the "SEC") on March 1, 2023 (as amended by Amendment No. 1 thereto ("Amendment No. 1") originally filed with the SEC on August 21, 2025, the "Schedule 13D"), with respect to the common stock, par value $0.0001 per share ("Common Stock"), of Solid Power, Inc. Except as indicated in this Amendment No. 2, all other information as to the Reporting Persons set forth in the Schedule 13D remains unchanged and capitalized terms used herein that are not defined herein have the same meanings as set forth in the Schedule 13D. The Reporting Persons have engaged in transactions since August 21, 2025, which represented a decrease in David M. Leuschen's and Pierre F. Lapeyre, Jr.'s respective beneficial ownership of Common Stock of more than 1% of the total number of shares of Common Stock outstanding. See Item 3 below for further detail regarding these transactions.
Item 3.	Source and Amount of Funds or Other Consideration
	Item 3 of the Schedule 13D is hereby amended by deleting the last paragraph thereof and adding the following: Securities Held Directly By REL Batavia Partnership, L.P. ("REL") and REL US Partnership, LLC ("REL US") 4,798,303 shares of Common Stock directly held by REL were issued in the Business Combination in exchange for securities of Legacy Solid Power directly held by REL prior to the Business Combination. In addition, REL purchased 2,000,000 shares of Common Stock at a price of $10.00 per share in a PIPE transaction that closed substantially concurrently with the closing of the Business Combination. Further, on January 23, 2023, Sponsor distributed 437,500 shares of Common Stock to REL US. On September 19, 2025, REL and REL US sold an aggregate of 7,235,803 shares of Common Stock at a price of $3.58 per share in the open market.
Item 5.	Interest in Securities of the Issuer
(a)	Item 5 of the Schedule 13D is hereby amended and restated in its entirety as follows: The ownership information presented below represents beneficial ownership of shares of Common Stock of the Issuer as of September 23, 2025, based upon (i) with respect to Mr. Leuschen, 185,291,240 shares of the Issuer's Common Stock, which includes (x) 181,284,380 shares of the Issuer's Common Stock, as reported in the Issuer's Quarterly Report on Form 10-Q filed with the SEC on August 7, 2025 and (y) 4,006,860 shares of the Issuer's Common Stock which may be purchased by exercising warrants that are presently exercisable and (ii) with respect to Mr. Lapeyre, 187,335,411 shares of the Issuer's Common Stock, which includes (x) 181,284,380 shares of the Issuer's Common Stock, as reported in the Issuer's Quarterly Report on Form 10-Q filed with the SEC on August 7, 2025 and (y) 6,051,031 shares of the Issuer's Common Stock which may be purchased by exercising warrants that are presently exercisable. Shared Shared Sole power power to Sole power power to to dispose or dispose or to Amount to vote or to vote or to to direct the direct the beneficially Percent of direct the direct the disposition disposition Reporting Person owned class: vote: vote: of: of: David M. Leuschen 6,704,303 3.62% 1,745,546 4,958,757 1,745,546 4,958,757 Pierre F. Lapeyre, Jr. 9,010,694 4.81% 4,051,937 4,958,757 4,051,937 4,958,757 Sponsor is the record holder of 951,897 shares of Common Stock and 4,006,860 Private Placement Warrants that are presently exercisable. Mr. Leuschen and Mr. Lapeyre are the managing directors of Riverstone, which is the sole and managing member of Sponsor Manager, which is the managing member of Sponsor. As a result, Mr. Leuschen and Mr. Lapeyre each may be deemed to share beneficial ownership of the shares held by Sponsor. Each such person or entity disclaims any such beneficial ownership. Mr. Leuschen is the record holder of 1,745,546 shares of Common Stock. Mr. Lapeyre is the record holder of 72,046 shares of Common Stock and 401,131 Private Placement Warrants that are presently exercisable. Additionally, Mr. Lapeyre may be deemed to beneficially own 1,935,720 shares of Common Stock and 1,643,040 Private Placement Warrants that are presently exercisable held by estate planning vehicles for which he serves as investment manager.
(b)	The information from the response in subpart (a) of this section is incorporated by reference herein.
(c)	Except as described in Item 3 of this Amendment No. 2, the Reporting Persons have not engaged in any transaction involving securities of the Issuer since the filing of Amendment No. 1.
(d)	This Item 5(d) is not applicable.
(e)	On September 19, 2025, Mr. Leuschen and Mr. Lapeyre ceased to be the beneficial owners of more than five percent of the Common Stock.
Item 7.	Material to be Filed as Exhibits.
	11 Joint Filing Agreement, dated February 28, 2023, among Decarbonization Plus Acquisition Sponsor III LLC, Decarbonization Plus Acquisition Sponsor Manager III, LLC, Riverstone Holdings LLC, Pierre F. Lapeyre, Jr. and David M. Leuschen (filed as Exhibit 2 to the Schedule 13D filed on March 1, 2023 and incorporated herein by reference). 12 Power of Attorney, dated August 21, 2025, granted by Pierre F. Lapeyre, Jr. (filed as Exhibit 8 to the Schedule 13D filed on August 21, 2025 and incorporated herein by reference). 13 Power of Attorney, dated August 21, 2025, granted by David M. Leuschen (filed as Exhibit 9 to the Schedule 13D filed on August 21, 2025 and incorporated herein by reference).

SIGNATURE

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.

David M. Leuschen

Signature:	/s/ Thomas Smith, attorney-in-fact
Name/Title:	David M. Leuschen
Date:	09/23/2025

Pierre F. Lapeyre, Jr.

Signature:	/s/ Thomas Smith, attorney-in-fact
Name/Title:	Pierre F. Lapeyre, Jr.
Date:	09/23/2025

FAQ

What ownership change does the Schedule 13D/A for SLDPW report?

The filing reports that David M. Leuschen now beneficially owns 6,704,303 shares (3.62%) and Pierre F. Lapeyre, Jr. beneficially owns 9,010,694 shares (4.81%) as of September 23, 2025.

Did the reporting persons sell shares of Solid Power (SLDPW)?

Yes. On September 19, 2025, REL and REL US sold an aggregate of 7,235,803 shares in the open market at $3.58 per share.

Were there any prior purchases disclosed in the filing for SLDPW?

Yes. REL purchased 2,000,000 shares in a PIPE at $10.00 per share that closed substantially concurrently with the business combination.

Do the reported ownership percentages include warrants?

Yes. The percentages include presently exercisable warrants: the filing references 4,006,860 and 6,051,031 shares exercisable upon warrant exercise in the respective calculations.

When did the reporting persons cease to be beneficial owners of more than 5%?

The Schedule 13D/A states that on September 19, 2025, Messrs. Leuschen and Lapeyre ceased to be beneficial owners of more than 5% of the Common Stock.