BMS 4S 30A Protection circuit with balancing function (OT3554)

This BMS (Battery Management System) ensures that when charging 4 batteries (such as the 18650) of 3.7V, all batteries are charged equally. Suppose that one of the 4 batteries is a bit older or charges a bit slower, then it may need a bit more charging time to reach the same level. The BMS ensures this. In addition, the BMS protects the batteries against short circuits, too much current or voltage, etc. Charging voltage: 16.8V Maximum charging current: 30A * Maximum continuous discharge current: 30A * Short circuit protection: 75 ± 5A Overcharge protection voltage (per cell/battery): 4.25 ± 0.05V Discharge protection voltage (per cell/battery): 2.55 ± 0.08VBalancing function: YesDimensions: 56x45x8mm*Note: These are the maximums of the BMS circuit. Connected batteries may not be able to handle this current!Pin description (See the images 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.Note: Making your own battery pack requires knowledge and skills. If the batteries or the BMW are connected incorrectly, batteries can catch fire or even explode.