New energy vehicle technology

　　The battery that provides the power source for the vehicle in the new energy vehicle is called the power battery. The function of the power battery is to receive and store the high-voltage DC power provided by the on-board charger, generator, braking energy recovery device or external charging device, and to provide high-voltage DC power for electric vehicles.

　　One, the role of power batteries

　　The battery that provides the power source for the vehicle in the new energy vehicle is called the power battery. The function of the power battery is to receive and store the high-voltage DC power provided by the on-board charger, generator, braking energy recovery device or external charging device, and to provide high-voltage DC power for electric vehicles.

　　New energy vehicle technology 4-power battery in new energy vehicles

　　Power battery is the core component of pure electric vehicles and one of the most expensive components in new energy vehicles. The performance of the power battery directly determines the actual value of this car.

　　The power battery in the pure electric vehicle is the power source of the entire vehicle. It replaces the petroleum energy of the transmission fuel vehicle and is equivalent to the "heart" of the pure electric vehicle. It provides continuous and stable energy for the vehicle to drive the vehicle.

　　Second, the classification of power batteries

　　There are various types of power batteries used in new energy vehicles. After technological development and alternation, the current new energy vehicles mainly include lead-acid batteries, nickel-hydrogen batteries, and lithium-ion batteries.　　New Energy Vehicle Technology 4-Power Battery in New Energy Vehicles

　　As the low-voltage auxiliary battery of new energy vehicles, lead-acid batteries provide low-voltage working electricity for the ordinary low-voltage electrical systems of vehicles. Lead-acid batteries are no longer used as power batteries.　　Ni-MH batteries are mainly used in Toyota's hybrid and plug-in hybrid vehicles, such as Toyota's ordinary hybrid Camry dual-engine, Corolla dual-engine, Ralink dual-engine, etc. The plug-in hybrid model Prius also uses nickel-hydrogen batteries.

　　Lithium-ion batteries are commonly used in pure electric vehicles, such as BYD E6, BAIC EV200/160, Roewe E50, Changan Yidong EV, BMW i3, etc. The characteristics of each type of power battery are shown in the table below.

　　New energy vehicle technology 4-power battery in new energy vehicles

　　Third, the application of nickel-hydrogen power battery

　　1. The characteristics of nickel-hydrogen battery 　　 Nickel-hydrogen power battery (hereinafter referred to as nickel-hydrogen battery) is an alkaline battery, which is a new type of green battery developed in the 1990s. In the 1990s, electric vehicles, especially hybrid electric vehicles, were applied on a large scale.　　 The characteristics of nickel-metal hydride batteries under the irregular charging and discharging conditions of hybrid vehicles hardly change, and nickel-metal hydride batteries are more suitable for hybrid vehicles.

　　The characteristics of NiMH batteries are as follows:

　　Ni-MH battery has many advantages such as pollution-free, high specific energy, high power, fast charge and discharge, durability and so on. Compared with lead-acid batteries, nickel-metal hydride batteries have the characteristics of high specific energy, light weight, small size, and long cycle life.

　　The basic unit of nickel-metal hydride battery is a single battery with a voltage of 1.2V, which can be combined into nickel-metal hydride battery assemblies with different voltages and different charges according to the requirements of use.

　　2. Application of Ni-MH battery

　　Toyota Prius, Camry Hybrid, Corolla Shuangqing, Ralink Shuangqing and other models use Toyota THS-Ⅱ hybrid drive system. The power battery adopts Ni-MH power battery. The battery is installed in the trunk behind the rear seat of the vehicle. The battery is composed of 34 battery modules, and the battery module is composed of six 1.2V single nickel-hydrogen batteries with a voltage of 7.2V. The nominal voltage of the power battery is 244.8V. The composition and installation location of the power battery are shown below.

　　Four, the principle and application of lithium electronic power battery

　　1. The characteristics of lithium electronic power battery

　　Lithium-ion batteries have the advantages of high energy density, high-power charging and discharging capabilities, and have gradually become the first choice for electric vehicles. According to different cathode materials, lithium-ion batteries on electric vehicles can be divided into lithium manganese oxide batteries, lithium cobalt oxide batteries, lithium iron phosphate batteries, and ternary lithium batteries.

　　BYD E6 electric vehicles, BAIC EV200/160, GAC New Energy AG, Roewe E50 all use lithium iron phosphate batteries, and Tesla electric vehicles generally use ternary lithium batteries.

　　There are two types of lithium-ion batteries: square and cylindrical. Lithium-ion batteries consist of a positive electrode, a negative electrode, a separator, an electrolyte, and a safety valve.

　　New energy vehicle technology 4-power battery in new energy vehicles

　　The charging temperature of lithium batteries should generally be limited to the range of 0～60℃. The battery temperature is too high will damage the battery and may cause an explosion; although the temperature is too low will not cause safety problems, but it is difficult to fully charge the battery.

　　2. Application of Lithium Electronic Battery

　　Currently, lithium electronic batteries are widely used in various types of electric vehicles at home and abroad.