Chip: SIM800L. Charging Module 1S 3.7V 2S 7.4V Lithium Li-ion 18650 Battery Cell 8.4V TP5100 XY. 10 String 10S 36V 37V 15A Li-ion Battery BMS PCB For Ebike Electric Bicycle XY. 2PCS 7S 29.4V BMS Protection Board Balance 18650 For Li-ion Lithium Battery XY.
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