BMS (Battery Management System) - a battery management system that is designed to monitor the status of batteries, control the process of charging / discharging the battery, etc.
Four batteries (18650) can be connected to this module at the same time. The features of this charge controller are: protection against short circuit (short circuit) and protection against overdischarge (overcharge). Also a feature of the module is to turn off the power supply for the batteries when reaching the maximum capacity of all batteries (balancing). The maximum operating current of this BMS controller is 40 A, and the quiescent current reaches up to 30 μA. The battery charge is switched off when the voltage reaches 4.25 - 4.35 V, and the discharge when the voltage drops to 2.3 - 3.0 V.
This module of the battery charge-discharge controller has 7 outputs:
16.8V: battery positive pole
0V: negative pole of the battery
4.2V: mid-point assembly of 1 and 2 batteries
8.4V: mid-point assembly of 2 and 3 batteries
12.6V: mid-point assembly of 3 and 4 batteries
-: negative charge / discharge terminal
+ positive charge / discharge terminal
If the maximum permissible value of the supply voltage is exceeded, the charge controller activates the "protection" mode. In order to restore the module, it is necessary to re-apply voltage to the input of the BMS board or wait a while until the charge controller automatically disables the protection.
The supply voltage range of the module is from 16.8 to 18.1 V. A boost converter with a current limiter can be used for charging. Please note that this module is not a charger.