BMS 4S 40A Li-Ion Lithium Battery 18650 Charger Pcb (OT3575)

Battery Management System (BMS) for a 4S battery pack. With this circuit you can safely create a battery pack from 4 series Li-ion/Li-Po batteries (cells). The circuit protects the battery pack against short circuit, too high voltage and too low voltage. In addition, the circuit ensures that the batteries are charged evenly (balance function).Specifications:Charging voltage: 16.8V - 18.1VMaximum charging current: 25A*Maximum continuous discharge current: 40A*Short circuit protection: 45 ± 5AOvercharge protection voltage (per cell/battery): 4.28 ± 0.05VDischarge protection voltage (per cell/battery): 2.55 ± 0.08VBalance function: YesDimensions: 56x45x2.6mm*Note: These are the maximums of the BMS circuit. Connected batteries may not be able to handle this current!Pin description (See the pictures for the connection diagram):B-: Minus cell/battery 1B1: Plus cell/battery 1, minus cell/battery 2B2: Plus cell/battery 2, minus cell/battery 3B3: Plus cell/battery 3, minus cell/battery 4B+: Plus cell/battery 4P+: Plus output battery pack P-: Minus output battery packUse the P+ and P- connections to charge and discharge the battery pack.Caution: Making a Li-ion/Li-Po battery pack requires expertise. Only make the pack if you know what you are doing. Incorrectly connecting the batteries and the BMS circuit may cause the batteries to catch fire or even explode.