When the solar panel power exceeds a certain level and the charging current is larger than the rated current, the controller will automatically lower the charging power and bring the charging current to the rated level. With defective LCD liquid crystal display, convenient user to identify system failure. Featuring a temperature compensation function, the controller can automatically adjust charging and discharging parameters in order to extend the battery's service life. A built-in maximum power point tracking algorithm can significantly improve the energy utilization efficiency of photovoltaic systems, and raise the charging efficiency by 15% to 20% compared with the conventional PWM method. Advanced digital power supply technologies raise the circuit's energy conversion efficiency to as high as 98%.