Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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Property, Plant and Equipment (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Property, Plant and Equipment, Net, by Type [Abstract]
Gross property and equipment	$ 42,197		$ 28,550
Accumulated depreciation	(7,219)		(6,468)
Net property and equipment	34,978		22,082
Depreciation and amortization expense	753	$ 544
Property, Plant and Equipment.
Property, Plant and Equipment, Net, by Type [Abstract]
Depreciation and amortization expense	751	$ 542
Commercial production equipment
Property, Plant and Equipment, Net, by Type [Abstract]
Gross property and equipment	9,758		9,139
Laboratory equipment
Property, Plant and Equipment, Net, by Type [Abstract]
Gross property and equipment	1,435		1,316
Leasehold improvements
Property, Plant and Equipment, Net, by Type [Abstract]
Gross property and equipment	5,199		4,674
Computer equipment
Property, Plant and Equipment, Net, by Type [Abstract]
Gross property and equipment	468		416
Furniture and fixtures
Property, Plant and Equipment, Net, by Type [Abstract]
Gross property and equipment	393		321
Construction in progress
Property, Plant and Equipment, Net, by Type [Abstract]
Gross property and equipment	24,944		12,684
Construction Of Second Dry Room
Property, Plant and Equipment, Net, by Type [Abstract]
Construction in progress	10,206		6,875
Expansion Of Sulfide-Based Solid Electrolyte Production
Property, Plant and Equipment, Net, by Type [Abstract]
Construction in progress	5,863		943
Construction Of Customized Equipment
Property, Plant and Equipment, Net, by Type [Abstract]
Construction in progress	$ 8,875		$ 4,866