Annual report pursuant to Section 13 and 15(d)

Segment information (Details)

v3.7.0.1
Segment information (Details) - USD ($)
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Segment Reporting Information [Line Items]    
Net sales $ 173,851,113 $ 146,181,011
Cost of Sales 135,768,642 118,234,935
Gross profit 38,082,471 27,946,076
Lithium Batteries [Member]    
Segment Reporting Information [Line Items]    
Net sales 112,128,757 78,624,405
Cost of Sales 87,721,456 63,644,284
Gross profit 24,407,301 14,980,121
Ni-MH Batteries [Member]    
Segment Reporting Information [Line Items]    
Net sales 57,211,657 64,566,252
Cost of Sales 43,163,019 50,842,135
Gross profit 14,048,638 13,724,117
New Materials [Member]    
Segment Reporting Information [Line Items]    
Net sales 4,510,699 2,990,354
Cost of Sales 4,884,167 3,748,516
Gross profit $ (373,468) $ (758,162)