In terms of major categories, there are two types of batteries for electric vehicles, storage batteries and fuel-powered lithium batteries. Storage batteries are suitable for pure electric vehicles, including lead-acid batteries, nickel-cadmium batteries and nickel-hydrogen batteries. Types of obsolete batteries, and today’s mainstream pure electric vehicles basically use lithium ion batteries, including lithium cobalt oxide batteries, such as Tesla products; lithium manganese oxide batteries, such as Toyota Prius and Nissan Leaf; Lithium iron phosphate batteries, such as BYD products, ZINORO 1E, etc.
Lead-acid batteries are the most commonly used new energy vehicle batteries. The electrode plates of lead-acid batteries are grids made of lead alloy. The electrolyte level is dilute sulfuric acid, and both plates are overturned with lead sulfate. When discharging, a chemical reaction in the opposite direction occurs. The advantage of lead-acid batteries is the electromotive force during discharge. Relatively stable, the disadvantage is that the specific energy is small, and it is highly corrosive to the environment.
Ni-MH batteries are widely used in hybrid new energy vehicles. They have a large energy density ratio, which can effectively extend the driving time of the vehicle; moreover, the discharge characteristics of the nickel-hydrogen battery are stable and the discharge curve is smooth, and the heat generation is small, but It is too large and polluted.
Compared with lead-acid batteries and nickel-metal hydride batteries, lithium-ion batteries have the advantages of higher working voltage, larger specific energy, smaller size, lighter weight, longer cycle life, lower self-discharge rate, no memory effect, and no pollution. Therefore, more and more More and more automobile manufacturers choose to use lithium-ion batteries as the power lithium-ion batteries for pure electric vehicles.
There are three most commonly used lithium-ion batteries, namely lithium cobalt acid lithium ion batteries, manganese acid lithium ion batteries, and iron phosphate lithium ion batteries. Lithium cobalt oxide batteries have high efficiency, large discharge current, high charging speed, and light weight; but the disadvantage is that the stability is relatively poor, which is why this battery technology is difficult to produce large-capacity battery cells. The cost of lithium-ion manganese batteries is slightly lower and not as aggressive as lithium cobalt oxide. It has better low-temperature performance and is more suitable for use in cold regions. However, the high-temperature stability is not good enough, it is easy to swell, and the cycle life decays faster.
Lithium iron phosphate battery is known as the safest vehicle battery technology, because compared with lithium cobalt oxide battery and lithium manganate battery, the stability of lithium iron phosphate battery, especially under high temperature conditions The sex should be more stable, and the chance of accidents such as fires when encountering accidents is also less. However, the efficiency of lithium iron phosphate batteries is not as good as the aforementioned two battery technologies. The weight required to store the same energy is about twice that of lithium cobalt oxide batteries. It is no wonder why this new battery technology is difficult to become the choice of high-performance electric sports cars. NS.