SLDP · Solid Power, Inc.

Represents shares of the issuer's common stock withheld to satisfy the reporting person's tax obligation upon the vesting of restricted stock units.

Represents shares of the issuer's common stock withheld to satisfy the reporting person's tax obligation upon the vesting of restricted stock units.

Represents shares of the issuer's common stock withheld to satisfy the reporting person's tax obligation upon the vesting of restricted stock units.

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.

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.

This sale was made pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 23, 2025 (the "10b5-1 Plan"). The 10b5-1 Plan was established to cover the reporting person's tax liability arising from vesting of restricted stock units.

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.

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.

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.

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.

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.

Represents stock units, which upon vesting of the unit, represent the right to receive one share of the issuer's common stock. The 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. The reporting person has elected to defer settlement pursuant to the Solid Power, Inc. Directors' Deferred Equity Compensation Plan.

Represents shares of the issuer's common stock withheld to satisfy the reporting person's tax obligation upon the vesting of restricted stock units.

Represents shares of the issuer's common stock withheld to satisfy the reporting person's tax obligation upon the vesting of restricted stock units.

Represents shares of the issuer's common stock withheld to satisfy the reporting person's tax obligation upon the vesting of restricted stock units.

Represents shares of the issuer's common stock withheld to satisfy the reporting person's tax obligation upon the vesting of restricted stock units.

Each restricted stock unit represents a contingent right to receive one share of the underlying common stock of the Issuer. The restricted stock units will vest in 16 equal quarterly installments commencing on June 30, 2026, and thereafter at the end of each fiscal quarter of the Issuer, subject to the reporting person continuing to be a service provider (as defined in the Solid Power, Inc. 2021 Equity Incentive Plan) through the applicable vesting date.

Each restricted stock unit represents a contingent right to receive one share of the underlying common stock of the Issuer. The restricted stock units will vest in 16 equal quarterly installments commencing on June 30, 2026, and thereafter at the end of each fiscal quarter of the Issuer, subject to the reporting person continuing to be a service provider (as defined in the Solid Power, Inc. 2021 Equity Incentive Plan) through the applicable vesting date.

Each restricted stock unit represents a contingent right to receive one share of the underlying common stock of the Issuer. The restricted stock units will vest in 16 equal quarterly installments commencing on June 30, 2026, and thereafter at the end of each fiscal quarter of the Issuer, subject to the reporting person continuing to be a service provider (as defined in the Solid Power, Inc. 2021 Equity Incentive Plan) through the applicable vesting date.

Represents shares of the issuer's common stock withheld to satisfy the reporting person's tax obligation upon the vesting of restricted stock units.

Represents shares of the issuer's common stock withheld to satisfy the reporting person's tax obligation upon the vesting of restricted stock units.

Represents shares of the issuer's common stock withheld to satisfy the reporting person's tax obligation upon the vesting of restricted stock units.

Represents shares of the issuer's common stock withheld to satisfy the reporting person's tax obligation upon the vesting of restricted stock units.

Represents shares of the issuer's common stock withheld to satisfy the reporting person's tax obligation upon the vesting of restricted stock units.

Represents shares of the issuer's common stock withheld to satisfy the reporting person's tax obligation upon the vesting of restricted stock units.

The reporting person is the sole member and sole manager of WestRiver Management, LLC.

Represents shares of the issuer's common stock withheld to satisfy the reporting person's tax obligation upon the vesting of restricted stock units.

Represents shares of the issuer's common stock withheld to satisfy the reporting person's tax obligation upon the vesting of restricted stock units.

Represents shares of the issuer's common stock withheld to satisfy the reporting person's tax obligation upon the vesting of restricted stock units.

Represents shares of the issuer's common stock withheld to satisfy the reporting person's tax obligation upon the vesting of restricted stock units.

Represents shares of the issuer's common stock withheld to satisfy the reporting person's tax obligation upon the vesting of restricted stock units.

Represents shares of the issuer's common stock withheld to satisfy the reporting person's tax obligation upon the vesting of restricted stock units.

Represents shares of the issuer's common stock withheld to satisfy the reporting person's tax obligation upon the vesting of restricted stock units.

This transaction was executed in multiple trades at prices ranging from $1.69 to $1.695. The price reported above reflects the weighted average price. The reporting person hereby undertakes to provide upon request to the SEC staff, the issuer, or a security holder of the issuer full information regarding the number of shares and prices at which the transaction was effected.

This transaction was executed in multiple trades at prices ranging from $1.565 to $1.67. The price reported above reflects the weighted average price. The reporting person hereby undertakes to provide upon request to the SEC staff, the issuer, or a security holder of the issuer full information regarding the number of shares and prices at which the transaction was effected.

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.

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.

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.

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.

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.

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.

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.

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 the 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.

Represents shares of the issuer's common stock withheld to satisfy the reporting person's tax obligation upon the vesting of restricted stock units.

Represents shares of the issuer's common stock withheld to satisfy the reporting person's tax obligation upon the vesting of restricted stock units.

Each restricted stock unit represents a contingent right to receive one share of the underlying common stock of the Issuer. The restricted stock units will vest as to 25% of the granted number on May 9, 2026, and the remaining 75% of the granted number will vest in 12 equal quarterly installments commencing on June 30, 2026, and thereafter at the end of each fiscal quarter of the Issuer, subject to the reporting person continuing to be a service provider (as defined in the Solid Power, Inc. 2021 Equity Incentive Plan) through the applicable vesting date.

Each restricted stock unit represents a contingent right to receive one share of the underlying common stock of the Issuer. The restricted stock units will vest as to 25% of the granted number on May 9, 2026, and the remaining 75% of the granted number will vest in 12 equal quarterly installments commencing on June 30, 2026, and thereafter at the end of each fiscal quarter of the Issuer, subject to the reporting person continuing to be a service provider (as defined in the Solid Power, Inc. 2021 Equity Incentive Plan) through the applicable vesting date.

Each restricted stock unit represents a contingent right to receive one share of the underlying common stock of the Issuer. The restricted stock units will vest as to 25% of the granted number on May 9, 2026, and the remaining 75% of the granted number will vest in 12 equal quarterly installments commencing on June 30, 2026, and thereafter at the end of each fiscal quarter of the Issuer, subject to the reporting person continuing to be a service provider (as defined in the Solid Power, Inc. 2021 Equity Incentive Plan) through the applicable vesting date.