A battery management system (BMS) is essential in a lithium ion battery build. Li-ion batteries are much more sensitive to voltage than lead acid, and can be dangerous if over- or under-charged. This BMS is for a 7S (25.9v nominal) lithium ion battery. It protects against over- and under-voltage as well as over-current, and ensures that the cells are balanced.
To wire, you will need to solder battery and charge/load ground to pads on the board. You will also need to tie each of the balance leads into the individual battery cells. Note that this does NOT have provision for separate charge and load, as some boards do. Balance wiring is included.
This BMS is suited for smaller projects, but don't expect it to be adequate to protect a large build such as an off-grid power wall. This is perfect for eBike and scooters up to 500 watts, as well as RC projects.
Battery type: 7-cell 3.7v nominal lithium ion battery. NOTE: Not suitable for LiFePO4 batteries
Balance current: 80mA at 4.20v
Overcharge cutoff: 4.3±.05v
Overcharge delay: 75 mS
Overcharge recovery: 4.1±.05v
Undercharge cutoff: 2.4±.08v
Undercharge delay: 5mS
Max continuous current: 20a
Max transient current: 30a
Power consumption: <500 uA
Protection type: load disconnect