In February 2021, extreme cold weather swept across Texas, who has its own power grid, causing widespread power outages and more than 4 million people suffering from power outages. During the disaster, due to the shutdown of a large number of power generation facilities and the shortage of power supply, many tragedies occurred.

　　Although in extreme weather, the power generation capacity of distributed photovoltaic systems will be greatly reduced, such as photovoltaic roof "Solar Roof" and household energy storage "Powerwall", but the household energy storage system can still provide electricity to deal with emergencies in a short period of time demand. Therefore, household energy storage systems are becoming an energy supply option to deal with extreme environmental changes.

　　Household energy storage systems are mainly composed of photovoltaic power generation components, inverter components, and battery components. Among them, the most important part of the battery components is that it can store the energy input in an unstable state and effectively store it, and then release it when the user needs it.

　　Before 2010, lead-acid batteries were the first choice for energy storage systems, but lead-acid batteries had many disadvantages, such as low energy-to-volume ratio, large capacity influence by temperature, and short service life.

　　In energy storage systems in the past decade, lithium iron phosphate batteries have become the first choice to replace lead-acid batteries. Because the energy density of lithium iron phosphate batteries can reach 4-5 times that of lead-acid batteries, and has obvious advantages in terms of safety, cycle life, fast charging and discharging performance.