In 2014, Lead-acid batteries accounted for more than 70% of the battery market and are widely used in communication equipment, backup power supply, and solar energy systems. However, due to its high maintenance cost, short battery life, and great pollution to the environment, it is gradually being replaced by lithium batteries. It is estimated that the market share of lithium-ion batteries will be reversed by 2025. Lithium iron phosphate (LFP) battery is 3.2v, the combined voltage is exactly the same as that of lead-acid battery, and at the same volume, LFP battery has higher energy density and lighter weight. It is the best alternative to lead-acid batteries.