144 0001880162 XXXXXXXX LIVE 0001844862 Solid Power, Inc. 001-40284 486 S. PIERCE AVE., SUITE E LOUISVILLE CO 80027 (303) 219-0720 Buettner-Garrett Joshua Officer Common Fidelity Brokerage Services LLC

900 Salem Street Smithfield RI 02917

187500 210000.00 181992040 03/06/2025 NASDAQ Common 03/06/2025 Option Granted - 03/20/2015 Issuer N 187500 03/06/2025 Cash N Joshua R. Buettner-Garrett

486 S. Pierce Ave. Suite E Louisville CO 80027

Common 12/16/2024 187500 201412.50 Joshua R. Buettner-Garrett

486 S. Pierce Ave. Suite E Louisville CO 80027

Common 01/06/2025 187500 392287.50 Joshua R. Buettner-Garrett

486 S. Pierce Ave. Suite E Louisville CO 80027

Common 02/10/2025 187500 246412.50 03/06/2025 09/01/2023 /s/ Gary Redman, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Joshua R. Buettner-Garrett