Stockholders' Equity - Common Stock Available for Future Issuance (Details) - shares	Sep. 30, 2022	Feb. 02, 2022	Dec. 31, 2021
Common Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Common stock available for future issuance (in shares)	70,449,992		237,569,857
Redeemable Convertible Preferred Stock [Member]
Common Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Common stock available for future issuance (in shares)			213,960,286
Common Stock Warrants [Member]
Common Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Common stock available for future issuance (in shares)		14,213,280
Common Stock Warrants, Public Warrants [Member]
Common Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Common stock available for future issuance (in shares)	9,199,947
Common Stock Warrants, Private Warrants [Member]
Common Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Common stock available for future issuance (in shares)	5,013,333
Share-Based Payment Arrangement, Option [Member]
Common Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Common stock available for future issuance (in shares)	18,724,863		20,747,909
Restricted Stock Units (RSUs) [Member]
Common Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Common stock available for future issuance (in shares)	2,755,058
Performance Shares [Member]
Common Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Common stock available for future issuance (in shares)	2,116,942
Restricted Stock [Member]
Common Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Common stock available for future issuance (in shares)			2,261,880
SES AI Corporation 2021 Plan [Member]
Common Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Common stock available for future issuance (in shares)	32,639,849	36,862,002
SES Holdings Pte. Ltd. 2021 Plan [Member]
Common Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Common stock available for future issuance (in shares)			599,782