Share-Based Payment (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Share-based Payment Arrangement [Abstract]

Schedule of stock option activity plan

Share options life	Number of shares		Weighted Average Exercise Price (US$)		Weighted Average Grant Date Fair Value (US$)		Weighted Average Remaining Contractual
Outstanding as of January 1, 2020	7,578,503		$	5.50	$	2.14	7.1
Grant	27,874,727			6.27		3.06
Forfeited	(1,196,158	)		3.89		2.04
Outstanding as of September 30, 2020	34,257,072		$	6.19	$	2.90	9.2
Expected to vest and exercisable as of September 30, 2020	34,257,072		$	6.19	$	2.90	9.2
Outstanding as of January 1, 2021	34,737,967			6.19		2.92	9.0
Forfeited	(1,186,220	)		6.27		3.13
Outstanding as of September 30, 2021	33,551,747		$	6.19	$	4.95	8.2
Expected to vest and exercisable as of September 30, 2021	33,551,747		$	6.19	$	4.95	8.2

Share options	Number of shares		Weighted average exercise price		Weighted average grant date fair value		Weighted average remaining contractual life
			(US$)		(US$)
Outstanding as of January 1, 2018	9,034,556		$	5.57	$	2.19	9.1
Granted	160,270			6.28	$	1.41
Forfeited	(384,684	)		6.28	$	2.42
Outstanding as of December 31, 2018	8,810,178		$	5.55	$	2.16	8.1
Forfeited	(1,231,675	)		5.83	$	2.27
Outstanding as of December 31, 2019	7,578,503		$	5.50	$	2.14	7.1
Granted	28,350,160			6.28	$	3.09
Forfeited	(1,190,696	)		3.89	$	2.04
Outstanding as of December 31, 2020	34,737,967			6.19		2.92	9.0
Expected to vest and exercisable as of December 31, 2020	34,737,967		$	6.19	$	2.92	9.0

Schedule of weighted average assumptions applied to options

	After modification
Exercise price(1)	$	4.37 – 6.28
Expected lives (years)(2)		4.5 – 9.4
Volatility(3)		47.6% – 53.1%
Risk-free interest rate(4)		1.26 – 1.87	%
Expected dividend yields(5)		0.00	%
Weighted average fair value of options modified	$	4.70 – 5.36

	Nine Months Ended September 30, 2021
Expected term (years)(1)	2.35
Volatility(2)	63.06%
Average correlation coefficient of peer companies(3)	0.7960
Risk-free interest rate(4)	0.31	%
Expected dividend yields(5)	0.00	%

Grant date	For the years ended December 31, 2018
Risk-free interest rate(1)	3.55	%
Expected dividend yield(2)	0.0	%
Volatility(3)	51.7	%
Exercise multiple(4)	2.2
Life of options(5)	10 years
Fair value of underlying ordinary shares(6)	$3.22
Grant date	For the years ended December 31, 2020
Risk-free interest rate(1)	1.54% ~ 1.61%
Expected dividend yield(2)	0.0%
Volatility(3)	50.2% ~ 51.8%
Exercise multiple(4)	2.2 ~ 2.8
Life of options(5)	10 years
Fair value of underlying ordinary shares(6)	$6.10 ~ $8.21

Schedule non-vested shares activity

	Number on Non-Vested Shares		Weighted Average Grant Date Fair Value per Share (US$)
Outstanding as of January 1, 2020	19,809,056		$	0.90
Forfeited	(71,494	)	$	1.42
Transfer from non-vested shares	3,289,837		$	1.14
Outstanding as of September 30, 2020	23,027,399		$	0.93
Outstanding as of January 1, 2021	23,027,399		$	0.93
Outstanding as of September 30, 2021	23,027,399		$	6.27

	Number of non-vested shares		Weighted average grant date fair value per share
			(US$)
Outstanding as of January 1, 2020	3,289,837		$	1.14
Transfer to non-vested share units	(3,289,837	)	$	1.14
Outstanding as of September 30, 2020	—			—
Outstanding as of January 1, 2021	—			—
Grant	197,940		$	9.60
Vested	(6,157	)	$	8.52
Outstanding as of September 30, 2021	191,783		$	9.63

	Number of non-vested shares		Weighted Average Grant date fair value per share
			(US$)
Outstanding as of January 1, 2018	7,008,101		$	0.87
Forfeited	(1,430,089	)	$	0.64
Outstanding as of December 31, 2018	5,578,012		$	0.93
Transfer to non-vested share units	(2,288,175	)	$	0.64
Outstanding as of December 31, 2019	3,289,837		$	1.14
Transfer to non-vested share units	(3,289,837	)	$	1.14
Outstanding as of December 31, 2020	—		$	—

	Number of non-vested share units		Weighted Average Grant date fair value per share
			(US$)
Outstanding as of January 1, 2018	18,235,550		$	0.97
Forfeited	(943,990	)	$	1.18
Outstanding as of December 31, 2018	17,291,560		$	0.96
Forfeited	(772,341	)	$	1.60
Transfer from non-vested shares	3,289,837		$	0.64
Outstanding as of December 31, 2019	19,809,056		$	0.90
Forfeited	(71,494	)	$	1.42
Transfer from non-vested shares	3,289,837		$	1.14
Outstanding as of December 31, 2020	23,027,399		$	0.93

Schedule of classification of stock-based compensation

	Three Months Ended September 30, 2021
Cost of sales	$	2,306
General and administrative		44,164
Research and development expenses		8,303
Selling and marketing expenses		3,518
Construction in process		103
Total	$	58,394