BMS module 4S with balance, 40A, 16.8V

Protection module for charging 4S lithium battery packs (example 4x18650), type BMS (Battery Management System) for cells with a nominal voltage of 3.7V (4.2V when fully charged).

It can be used for creating dedicated batteries for tools.

This BMS is equipped with a cell balancing function, increasing the durability and performance of the battery used. All cells will be charged to the same level. Balancing is achieved by applying a resistor to the line with a higher voltage than the others, thus allowing the cells with a lower charge to catch up with the cells that have a higher voltage.

Balancing is a function that corrects small differences that may occur during charging, but a large difference between cells cannot be corrected by the internal balancing function. Use only batteries that are identical in specifications, capacity, and internal resistance.

The BMS has two pads, marked CD and FD. CD represents the signal indicating that the charging is finished, FD represents the signal indicating the discharge state.

Specifications:

Version: with Balancing

Battery charging voltage: 16.8V

Maximum discharge current: 40A (with good heat dissipation)

Maximum charging current: 10A (check battery specifications)

Balancing: Passive (through resistor)

Balancing current: 50mA

Dimensions mm: 60.5 x 45.2 x 3.4mm

Failure to follow the wiring diagram when installing components and making connections will result in module damage.