SUBSEQUENT EVENTS (Details) - Subsequent Event [Member] - USD ($)	Sep. 06, 2018	Sep. 10, 2018
Subsequent Event [Line Items]
Sales of batteries subject to product recall		$ 338,000
Value of commercial product recall inventory		1,000,000
Insurance deductible per occurrence of product recall		$ 50,000
Credit Agreement, with Minnesota Bank and Trust [Member]
Subsequent Event [Line Items]
Loan origination fees	$ 60,000
Credit Agreement, with Minnesota Bank and Trust [Member] | Revolving Loan [Member]
Subsequent Event [Line Items]
Proceeds from issuance of debt	$ 2,000,000
Maturity date	Sep. 06, 2019
Interest rate	4.50%
Default interest rate increased	3.00%
Late payment percentage charge	5.00%
Credit Agreement, with Minnesota Bank and Trust [Member] | Revolving Loan [Member] | Prime Rate [Member]
Subsequent Event [Line Items]
Interest rate description	The Revolving Loan matures on September 6, 2019 unless earlier terminated pursuant to its terms and bears interest at the greater of (a) 4.5% or (b) the difference of the prime rate as published in the Money Rates section of the Wall Street Journal minus 0.50%.
Interest rate, basis spread on variable rate	0.50%
Credit Agreement, with Minnesota Bank and Trust [Member] | Term Loan [Member]
Subsequent Event [Line Items]
Proceeds from issuance of debt	$ 5,000,000
Maturity date	Oct. 01, 2025
Interest rate	5.53%
Periodic payment	$ 71,921.43
Default interest rate increased	3.00%