Intangible asset, net (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011
Finite-Lived Intangible Assets [Line Items]
Intangible asset, net	$ 712,500		$ 712,500		$ 750,000
Consumer Battery License Fee [Member]
Finite-Lived Intangible Assets [Line Items]
Cost	1,000,000		1,000,000		1,000,000
Accumulated amortization	(287,500)		(287,500)		(250,000)
Intangible asset, net	712,500		712,500		750,000
Consumer battery license agreement period			20 years
Amortization expenses	$ 12,500	$ 12,500	$ 37,500	$ 37,500