Lithium-ion battery with light weight, large energy storage, power, pollution-free and so on, more and more widely used in various fields, its research and production have made great progress. Lithium-ion battery as a motive power in electric vehicles has become a new trend in the development of electric vehicles.

Lithium-ion battery technology advances and applications in emerging key markets (in the field of electric vehicles) have sparked a worldwide boom in research and development, so lithium-ion batteries are bound to play an important role in the field of electric vehicles and new energy. Currently in electric vehicles, more lithium-ion battery is lithium iron phosphate battery, its thermal stability and safety is better, while the price is relatively cheap. These factors make lithium iron phosphate batteries become the preferred small electric vehicles and PHEV battery. However, lithium-ion batteries, lithium-ion battery than the energy, specific power and operating voltage is relatively low, in the application of large pure electric vehicles lithium cobalt oxide and lithium manganese oxide batteries and so on more advantages.

However, there are also some problems with the widespread use of lithium battery electric vehicles, mainly due to the performance limitations of lithium batteries, including lithium-ion battery safety, cycle life, cost, operating temperature and material supply