E&J technology group developed developed bluetooth active balancer with RS485 CANBus support 2S-24S lto lifepo4 li-ion battery packs. The bluetooth APP can monitor each string cell voltage and can send out signal by RS485/CANBus to give external relay to control the charging/discharging. More details or other custom development needed on our active battery balancers, feel free to contact us anytime. You can get touch with us through email sales@ejtechgroup.com