X0508 4 2025-05-21 0001844862 Solid Power, Inc. SLDP 0001174968 ANDERSON ERIK J C/O SOLID POWER, INC. 486 S. PIERCE AVE., SUITE E LOUISVILLE CO 80027 1 0 Common Stock 2025-05-21 4 A 0 118808.0000 0.0000 A 260370.0000 D Common Stock 187617.0000 I By WestRiver Management, LLC 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 187,617 shares owned directly by WestRiver Management, of which the reporting person is the sole member and sole manager. /s/ Erik J. Anderson 2025-05-22