Between the upper and lower ends of the battery is the electrolyte of the battery, and the battery is hermetically sealed by a metal casing. When the LiFePO4 battery is charged, the lithium ions Li in the positive electrode migrate to the negative electrode through the polymer separator; during the discharge process, the lithium ions Li in the negative electrode migrate to the positive electrode through the separator.Stabilize the power grid: restrain the short-term impact of the microgrid, so that the microgrid can operate stably in the grid connected/isolated mode; Provide short-term stable power supply. Improve the power quality and increase the economic benefits of the microgrid.Good high temperature performance: The electric heating peak of lithium iron phosphate can reach 350°C-500°C, while lithium manganese oxide and lithium cobalt oxide are only around 200°C. The working temperature range is wide (-20C--75C), and it has high temperature resistance. The electric heating peak of lithium iron phosphate can reach 350℃-500℃, while lithium manganese oxide and lithium cobalt oxide are only around 200℃.