2-Cell 7.4V 20A 18650 BMS Battery Management System with Balancer

Applicable scope: Suitable for lithium batteries with nominal voltage of 3.7V and full voltage of 4.2V (including 18650, 26650, polymer lithium batteries, without limitation on the dimensions)

Product Size: 45*15*3.4mm (Standard), 48*20*3.4mm (Balancing)


Charging voltage: 8.4V - 9.0V

Continuous discharge current (upper limit): 20A (If the cooling environment is not good, reduce the load current use)

Continuous charge current (upper limit): 10A

Standard Edition: Suitable for starting drills with currents up to 25A below 50W, or resistive loads below 168W.

Balanced version: Suitable for starting currents below 25A and below 50W power drills, or resistive loads below 168W, with balanced charging function.
Note 1: The successful start of power drill requires two 10C-20C power batteries, or four 5C-10C power batteries (ordinary 18650 can not start drill! ! !); 0V and 8.4V cable, use 2 square mm Above copper wire (cannot use nickel plate!!!)

Note 2: Connect 0V, 4.2V, 8.4V according to the diagram strictly. When connecting the battery for the first time, it needs to be charged before output.


Note 3: When the battery is charged, “430” resistance heating is a normal phenomenon, indicating that the equalizing circuit is working; if the “430” resistance is also heating in the state of not charging, please check whether the wrong line is connected.

For some customers with poor electronic foundation, please explain: Do not mix good batteries and bad batteries together! The capacity/internal resistance of 2 batteries should be as close as possible! (1 good battery + 1 bad battery = 2 battery use effect).

Package Include:

1* BMS board