Business Combination - Number of common stock shares outstanding (Details) - shares |
12 Months Ended | |
|---|---|---|
Dec. 31, 2021 |
Dec. 31, 2020 |
|
| Business Acquisition [Line Items] | ||
| Less: redemption of DCRC Class A common stock | (210,171) | |
| Shares of Common Stock issued in PIPE Financing | 19,500,000 | |
| Total shares of Common Stock outstanding immediately after Business Combination | 167,557,988 | 69,885,084 |
| Legacy Solid Power | ||
| Business Acquisition [Line Items] | ||
| Number of common stock shares issued | 104,518,159 | |
| Class A Common Stock | ||
| Business Acquisition [Line Items] | ||
| DCRC common stock outstanding prior to Business Combination | 43,710,000 | |
| Class B Common Stock | ||
| Business Acquisition [Line Items] | ||
| DCRC common stock outstanding prior to Business Combination | 40,000 |