Purely electric vehicles are vehicles that are powered by vehicle-borne power and are wheeled with electric power and that meet the requirements of road traffic and safety regulations. The outlook is widely appreciated because of the relatively small environmental impact on traditional cars, but the current technology is not yet mature. Purely electric vehicle (battery electric vehicle, known as bev) is a vehicle that is fully powered by chargeable batteries (e. G. Lead-acid, nickel cadmium, nickel hydrogen or lithium ion batteries). Although it has a long history of 134 years, it has been limited to certain specific areas of application, with smaller markets. This is mainly due to the prevalence of severe disadvantages such as high prices, short life expectancy, high outer size and weight, and long recharge times due to various types of batteries. As early as 2001, our country launched a scientific project to make electric vehicles an important research project, with a multi-year t...