Solid Power (SLDP) director receives 44,133 restricted stock units as equity grant

Rhea-AI Filing Summary

Solid Power, Inc. director Aleksandra A. Miziolek received an award of 44,133 restricted stock units of common stock. These units were granted at no cash cost per share and will each convert into one share of common stock when they vest.

The restricted stock units vest on the earlier of the first anniversary of the grant date or the day before Solid Power, Inc.’s next annual meeting of stockholders, provided she continues as a service provider under the company’s 2021 Equity Incentive Plan through that date. After this grant, she holds 341,062 shares of common stock directly.

Insider Trade Summary

1 transaction reported

Mixed 1 txn

Insider Miziolek Aleksandra A

Role null

Type	Security	Shares	Price	Value
Grant/Award	Common Stock	44,133	$0.00	--

Holdings After Transaction: Common Stock — 341,062 shares (Direct, null)

Footnotes (1)

1. [object Object]

Key Figures

RSUs granted: 44,133 units Grant price: $0.0000 per share Shares held after grant: 341,062 shares +1 more

4 metrics

RSUs granted 44,133 units Restricted stock units of common stock granted to director

Grant price $0.0000 per share Equity award, non-cash compensation

Shares held after grant 341,062 shares Director’s direct common stock ownership post-transaction

Vesting schedule Earlier of 1-year anniversary or day before next annual meeting Subject to continued service as a service provider

Key Terms

restricted stock units, Solid Power, Inc. 2021 Equity Incentive Plan, annual meeting of stockholders

3 terms

restricted stock units financial

"Represents restricted stock units, which upon vesting of the unit, represent the right to receive one share"

Restricted stock units are a type of company reward where employees are promised shares of stock, but they only fully own these shares after meeting certain conditions, like staying with the company for a set time. They matter because they can become valuable assets and are often used to motivate employees to help the company succeed.

Solid Power, Inc. 2021 Equity Incentive Plan financial

"subject to the reporting person continuing to be a service provider (as defined in the Solid Power, Inc. 2021 Equity Incentive Plan)"

annual meeting of stockholders financial

"the day before the issuer's next annual meeting of stockholders following the grant date"

Form 4 Insider Transactions: What Each Field Means →

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Miziolek Aleksandra A

(Last) (First) (Middle)

C/O SOLID POWER, INC.

486 S PIERCE AVE., SUITE E

(Street)

LOUISVILLE COLORADO 80027

(City) (State) (Zip)

UNITED STATES

(Country)

2. Issuer Name and Ticker or Trading Symbol
Solid Power, Inc. [ SLDP ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director		10% Owner
	Officer (give title below)		Other (specify below)

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
05/20/2026

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

4. If Amendment, Date of Original Filed (Month/Day/Year)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	05/20/2026		A		44,133(1)	A	$0	341,062	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. Represents restricted stock units, which upon vesting of the unit, represent the right to receive one share of the issuer's common stock. The restricted stock units vest upon the earlier of: (i) the first anniversary of the grant date or (ii) the day before the issuer's next annual meeting of stockholders following the grant date, in each case, subject to the reporting person continuing to be a service provider (as defined in the Solid Power, Inc. 2021 Equity Incentive Plan) through such vesting date.

	/s/ Kristen Gould, attorney-in-fact on behalf of Aleksandra A. Miziolek	05/21/2026
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.
* Form 4: SEC 1474 (03-26)

FAQ

What did Solid Power (SLDP) director Aleksandra Miziolek receive in this Form 4?

She received 44,133 restricted stock units of Solid Power common stock. Each unit represents the right to receive one share upon vesting, granted at no cash cost per share as equity-based compensation under the company’s 2021 Equity Incentive Plan.

How do the new restricted stock units for SLDP’s director vest?

The restricted stock units vest on the earlier of the first anniversary of the grant date or the day before Solid Power’s next annual stockholders’ meeting. Vesting is conditioned on the director continuing to serve as a service provider through the applicable vesting date.

How many Solid Power (SLDP) shares does Aleksandra Miziolek hold after this grant?

Following the award, she directly holds 341,062 shares of Solid Power common stock. This total includes the impact of the 44,133 restricted stock units reported in the filing, reflecting her updated direct ownership position after the equity grant.

Was the SLDP director’s equity award a market purchase or a compensation grant?

It was a compensation grant, coded as a grant, award, or other acquisition. The 44,133 restricted stock units were awarded at a price of $0.0000 per share, reflecting non-cash equity compensation rather than an open-market stock purchase.

What plan governs the restricted stock units granted to the SLDP director?

The units were granted under the Solid Power, Inc. 2021 Equity Incentive Plan. This plan defines service providers, outlines vesting conditions, and governs how restricted stock units convert into shares of common stock upon satisfaction of the vesting requirements.