The 36V/10Ah (360Wh) lead-acid battery has a weight of 12kg. It can travel about 50km with a single charge, and the charging frequency is about 100 times. The usage time is about 1 year. If the lithium iron phosphate power battery is used, the same 360Wh energy (12 10Ah batteries are connected in series), the weight is about 4kg, the charging can walk about 80km, the charging frequency can reach 1000 times, and the service life can reach 3 to 5 years. Although the price of lithium iron phosphate battery is much higher than that of lead-acid batteries, the overall economic effect is better with lithium iron phosphate power batteries and is lighter in use. The performance of lithium-ion battery is mainly determined by the positive and negative materials. Lithium iron phosphate as a lithium battery material has only appeared in recent years. The domestic development of large-capacity lithium iron phosphate battery was July 2005. Its safety performance and cycle life are incomparable to other materials, which are the most important technical indicators of power batteries. 1C charge and discharge cycle life of 2000 times. Single cell battery overcharge voltage 30V does not burn, puncture does not explode. Lithium iron phosphate cathode materials make large-capacity lithium-ion batteries easier to use in series. To meet the needs of electric vehicles for frequent charging and discharging. It has the advantages of non-toxic, non-polluting, good safety performance, wide source of raw materials, low price and long service life. It is an ideal cathode material for a new generation of lithium ion batteries. This project belongs to the development of functional energy materials in high-tech projects, and is the key area supported by the national “863” plan, “973” plan and “Eleventh Five-Year” high-tech industry development plan. The positive electrode of lithium-ion battery is lithium iron phosphate material, which has great advantages in safety performance and cycle life. These are one of the most important technical indicators of power battery. 1C charging and discharging cycle life can be achieved 2000 times, the puncture does not explode, it is not easy to burn and explode when overcharged. Lithium iron phosphate cathode materials make large-capacity lithium-ion batteries easier to use in series.