In response to the pressure of energy needs, countries around the world have adopted strategies such as improving energy structures and developing renewable energy sources. Solar photovoltaic (PV), as a representative of renewable energy, has been widely used. PV power supply is different from traditional power. For PV-lithium-ion battery energy storage systems, the passive equalization circuit and control strategy are used to equalize high-performance batteries and to obtain excellent temperature rise. The equalization control strategy proposed in this paper is divided into two parts: passive equalization control strategy and active equalization control strategy. Passive equalization. The printed circuit board we made for the experimental platform is shown in Figure 6. The microcontroller unit we use is MC9S12XEQ, LTC6803 is used to sample the battery voltage because it has very high accuracy and RS422.