Installed on the negative pole of the car’s 12V lead-acid battery to collect the three physical quantities of voltage U, current A and temperature T, the microprocessor μC then estimates in real time according to the internal software algorithm, the battery’s state of charge (S0C) and health can be obtained. State (SOH) and State of Function (SOF), through LIN communication, send the relevant information state to the upstream control unit ECU to facilitate energy management, and realize the start-stop function of the engine and the intelligent generator control function, and reduce CO2 emissions , Reduce fuel consumption.