A BMS will ensure the safe operation of battery cells (either individual cells or packs).
The BMS will perform any/all of the following functions:
- Monitor/protect from Over/Under conditions (Voltage, Current, Temperature)
- Support different limits for specific chemistries
- (LiCoO2, LiMn2O4, LiNiMnCoO2 (NMC), LiFePO4 LiFePO4, etc)
- Cell Balancing for battery cells/packs in series (to prolong battery life)
- Fuel Gauge, provide State-of-Charge (SOC), State-of-Health (SOH)
- Communicate using standard protocols (SMBus, I2C, SPI, CAN, RS485, BT, Wifi)
BMS architectures can range from simple 2V/100µA to highly complex 600V+/500A+ with design requirements ranging from simple protectors to full systematic design.
These next design examples show the increased complexity as of BMS designs as the trend for higher power continues.