The function of the solar battery module is to convert solar energy into electric energy, supply the load to work or charge the battery pack; the function of the controller is to protect the charging and discharging of the battery pack; the battery pack is used to store electric energy; the function of the inverter is to convert the direct current Convert to alternating current. At night or on cloudy and rainy days, when the solar cell components cannot work, the battery pack is used to supply power to the load. The working mode of the battery can be divided into two types: recycle use and float charge use. It is often in the working state of frequent charge and discharge, that is, cyclic use; often in the state of charge, it is used for floating charge, which can make up for the capacity loss of the battery due to self-discharge. VRLA batteries used in photovoltaic power generation systems belong to a recycling method. The composition of the photovoltaic power generation system. The photovoltaic off-grid power generation system is a power generation system that uses the principle of photoelectric effect to convert solar energy into electrical energy. It is usually composed of solar cell components, controllers, battery packs, DC/AC inverters, etc. Photovoltaic power generation systems are mostly built in remote mountainous areas, plateaus, and Gobi. The natural environment is very harsh and the working environment temperature varies widely. The battery in photovoltaic power generation system has the following requirements: (1) has deep cycle discharge performance and long charge and discharge cycle life; (2) has strong overcharge resistance; (3) has strong capacity recovery ability after overdischarge; (4) good Charge acceptance; (5) when the battery is used in a static environment, the electrolyte is not easy to layer; (6) has maintenance-free or low-maintenance performance; (7) should have good high and low temperature charge and discharge characteristics; (8) It can adapt to the use environment in high altitude areas; (9) The batteries in the battery pack have good consistency.