Battery Management and Protection Systems for building high current power sources using low cost Lithium Battery cells of 6 to 15 battery cells. Built-in Precision voltage sensors and current sensors for accurate State of Charge and State of Health monitoring. Built-in switches to load and charger. Overload, short-circuit, over or under voltage, or over temperature protection. USB, CANbus, RS485, PWM or Bluetooth (optional) Communication.