Analysis of five types of new energy vehicle batteries

As a relatively mature technology, lead-acid batteries are still the only batteries for electric vehicles that can be processed in large quantities because of their low cost and high-rate discharge. There are 20 electric vehicles using lead-acid batteries to provide transportation services for the Olympic Games. However, the specific energy, specific power and energy density of lead-acid batteries are very low. Electric vehicles using this as a power source (600405, shares) (600405, shares) cannot have good speed and cruising range. 2. Although nickel-cadmium batteries and nickel-metal hydride batteries have better performance than lead-acid batteries, they contain heavy metals and will pollute the environment after being used and abandoned. Ni-MH power lithium batteries have just entered a mature stage, and are currently the only battery system that has been practically verified, commercialized, and large-scale in the battery system used in hybrid vehicles. The current 99% of the market share of the existing hybrid lithium batteries is nickel-hydrogen power lithium. Battery, the representative of commercialization is Toyota's Prius. At present, the world’s important automotive power lithium battery manufacturers include Japan’s PEVE and Sanyo. PEVE occupies 85% of the global market share of nickel-hydrogen batteries for hybrid power vehicles. At present, important commercial hybrid vehicles such as Toyota Prius, Alphard and Estima , And Honda’s Civic, Insight, etc. all use PEVE’s Ni-MH power lithium battery pack. In my country, Changan Jiexun, Chery A5, FAW Pentium, GM Grand Hyatt and other brand cars have been in demonstration operation. They also use nickel-metal hydride batteries, but the batteries are mainly purchased from abroad. The use of domestic nickel-metal hydride batteries in automobiles It is still in the Ru0026D matching stage. 3. Lithium-ion batteries Traditional lead-acid batteries, nickel-cadmium batteries, and nickel-hydrogen batteries have relatively mature technologies, but their use in automobiles as power lithium batteries has major problems. At present, more and more automobile manufacturers choose to use lithium-ion batteries as the power lithium batteries for new energy vehicles. Because lithium-powered lithium batteries have the following advantages: high working voltage (3 times that of nickel-cadmium batteries, hydrogen-nickel batteries); large specific energy (up to 165WH/kg, 3 times that of nickel-hydrogen batteries); small size; light ; Long cycle life; low self-discharge rate; no memory effect; no pollution, etc. At present, many well-known automakers are committed to the development of power lithium-ion battery vehicles, such as Ford and Chrysler in the United States, Toyota, Mitsubishi, Nissan, Hyundai in South Korea, Courreges, and Ventury in France. Domestic automakers BYD, Geely, Chery, Lifan, ZTE and other automakers have also equipped their hybrid and pure electric vehicles with power lithium-ion batteries. The current bottleneck hindering the development of power lithium-ion batteries is: safety performance and the management system of automobile power lithium batteries. In terms of safety performance, due to the high energy density, high working temperature, harsh working environment and other reasons of lithium power lithium batteries, coupled with the people-oriented safety concept, users have put forward very high requirements for battery safety. Regarding the management system of automobile power lithium battery, since the working voltage of the automobile power lithium battery is 12V or 24V, and the working voltage of a single power lithium ion battery is 3.7V, it is necessary to increase the voltage by connecting multiple batteries in series, but it is difficult for the battery Achieve completely uniform charging and discharging, so that a single battery in multiple battery packs in series will be unbalanced, and the battery will be undercharged and over-discharged, and this situation will lead to a sharp deterioration in battery performance , Eventually leading to the entire set of batteries not working properly, or even scrapped, which greatly affects the service life and reliability of the battery. 4. Lithium iron phosphate battery Lithium iron phosphate battery is also a kind of lithium ion battery, its specific energy is less than half of lithium cobalt oxide battery, but its safety is high, the number of cycles can reach 2000 times, the discharge is stable, and the price is cheap , Become a new choice for vehicle power. The iron battery proposed by BYD, the industry believes that it is more likely to be a lithium iron phosphate battery. Fifth, fuel power cell Simply put, a fuel cell (FuelCell) is a power generation device that directly converts the chemical energy in the fuel and oxidant into electrical energy. Fuel and air are fed into the fuel power cell separately, and electricity is wonderfully processed. It looks like a battery with positive and negative poles and electrolytes from the outside, but in fact it cannot store electricity but is a power plant. The most promising one for automobiles is the proton exchange membrane fuel power cell. Its working principle is: sending hydrogen gas to the negative electrode, after the use of a catalyst (platinum), the two electrons in the hydrogen atom are separated, and these two electrons are attracted by the positive electrode, and a current flows through the external circuit and loses the hydrogen of the electrons. Ions (protons) can pass through the proton exchange membrane (solid electrolyte) and recombine with oxygen atoms and electrons to form water at the positive electrode. Since oxygen can be obtained from the air, as long as the anode is continuously supplied with hydrogen and the water (steam) is taken away in time, the fuel power cell can continuously supply electric energy. Disclaimer: Some pictures and content of articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous article: What is a power lithium battery? How is it different from ordinary batteries