Electronic control circuits known as battery management systems (BMS) are used to monitor and manage the charging and discharging of batteries. Battery management system's job is to make sure that a battery's remaining energy is used as efficiently as possible. BMS systems shield batteries from deep discharge and over-voltage, which are caused by extremely quick charging and extremely high discharge current, in order to prevent overloading the batteries. To ensure that various battery cells have the same charging and discharging requirements, the battery management system also offers a cell balancing function in the event of multi-cell batteries.

A 6 string 22V circuit power tool known as the 6S BMS 12A 22V 18650 Lithium Battery Protection Board is mostly used for solar illumination, for dedicated 18650 battery packs.

• Short circuit, Overcharge, Over-discharge, and Overcurrent protection.
• Includes a Current fuse
• Includes protective plate with a sampling resistor
• Ultra-high temperature charge and discharge capabilities

• B+ connect Battery positive end;
• B1 connect the point between battery 1 and battery 2
• B2 connect the point between battery 2 and battery 3
• B3 connect the point between battery 3 and battery 4
• B4 connect the point between battery 4 and battery 5
• B5 connect the point between battery 5 and battery 6
• B- battery negative end
• P+ Charge/discharge positive end
• P- charge/discharge negative end

• Charging Voltage : 22 V
• Charging Current : 12 A (Max)
• Operating Temperature : -40°C - 85°C
• Maximum lampshift discharge current : 12 A
• Overcharge detection voltage : 4.25 V ± 0.05 V
• Over-discharge detection voltage : 2.50 V ± 0.08V
• Overcurrent Protection : 50 A
• Dimensions : 53 x 35.5 x 3.5 mm