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I thougt that the BMS would manage the balancing so that you could use an ac-dc brick for charging. Or is it the balancing cable breakout only for balancing the cells every once in a while?
I made me a similar one, but i skipped the cord and just installed a 3,5mm audio jack instead. That way i could use a cable with built in handsfree when i used the headphones at work. After a while i got tired of the cable getting stuck in stuff all the time, so i ordered a cheap bluetooth dongle with built in battery and handsfree, now it works great! :)http://www.gearbest.com/car-audio/pp_198640.html
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