At present, the classification of new energy car battery types is mainly distinguished from two aspects, one is the battery materials, and the other is the shape of the battery package. According to battery materials, the car battery types can be divided into ternary lithium batteries, lithium iron phosphate batteries, lithium cobalt oxide batteries, lithium manganese oxide batteries, nickel batteries, and lead-acid batteries. According to the battery packaging shape, the car battery types can be divided into cylindrical batteries, square batteries and pouch batteries.
1. Car battery types classification by battery materials
① Ternary lithium battery
In the car battery types, ternary lithium batteries are very common. The advantages are high capacity density and super endurance. The disadvantage is that the safety is relatively poor, especially when the safety performance will decrease at high temperature. However, ternary lithium batteries are still superior to lithium cobalt oxide batteries, so they are widely used. Whether it is Tesla, BMW, or Audi's new energy models, they all use ternary lithium batteries. CATL has seized the trend of ternary lithium batteries.
② Lithium iron phosphate battery
Speaking of lithium iron phosphate batteries, the first thing that comes to mind is BYD Auto. BYD has always insisted on research and development of lithium iron phosphate batteries in car battery types, and is in an absolute leading position. The advantage of lithium iron phosphate battery is that it is very safe and stable, the number of cycles can reach 2000, and it will not explode whether it is high temperature or impact.
The disadvantages are also obvious, that is, the energy density is low, and more space and weight are required under the same power condition. The use of ternary lithium batteries is gradually promoted in private cars, while lithium iron phosphate batteries are still used in buses.
③ Lithium cobalt oxide battery
Among car battery types, lithium cobalt oxide battery is a relatively early power battery. Before Tesla launched the Model S, it launched a Roster, which is a lithium cobalt oxide battery. The advantages of lithium cobalt oxide batteries are relatively large capacity density and high energy density, and the battery per unit volume can store more electricity. The disadvantage is that the thermal characteristic bottleneck is large, the cost is high, and the stability is very poor. It is generally used in the field of digital electronics, and electric vehicles have high requirements for the safety of power batteries, so Tesla also gave up lithium cobalt oxide batteries in the future.
④ Lithium manganese oxide battery
Lithium manganese oxide battery is also a relatively mainstream power battery in car battery types at present. Although it is not outstanding in all aspects, it is very balanced, with strong comprehensive ability, medium energy density and low price. Lithium manganese oxide batteries are safe and environmentally friendly, and are more in line with the needs of Japanese and Korean car manufacturers, so Japanese and Korean manufacturers use them more, and China mainly uses them for some light-duty car manufacturers.
⑤ Nickel batteries
Before the invention of nickel-metal hydride batteries, nickel-cadmium batteries had occupied a large part of the battery market and were recognized by the market. However, after the invention of nickel-metal hydride batteries, they quickly occupied the market share of nickel-cadmium batteries. In the car battery types, nickel-cadmium batteries contain heavy metals, which will pollute the environment after being used and discarded.
Nickel-metal hydride batteries are relatively environmentally friendly and have basically no pollution to the environment. In terms of discharge rate, the discharge rate of nickel metal hydride batteries is higher than that of nickel cadmium batteries. In terms of service life, under the same conditions, nickel metal hydride batteries are longer than nickel cadmium batteries. The nickel-metal hydride power battery has just entered the mature stage, and it is the only battery system used in hybrid electric vehicles that has been actually verified and commercialized and scaled up.
⑥ Lead-acid battery
Lead-acid battery is a relatively mature technology of car battery types, which is relatively low in cost and can be discharged at a high rate. However, compared lead acid vs lithium ion, the specific energy, specific power and energy density of lead-acid batteries are very low, and it is impossible for electric vehicles using this as a power source to have good speed and cruising range.
2. Classification of car battery types by packaging shapes
① Cylindrical battery
Cylindrical lithium battery is the battery variety that has been studied and analyzed more and has the most comprehensive technical discussion. A single cylindrical battery is mainly composed of cathode, anode, separators, cathode and anode collectors, valves, overcurrent protection devices, insulators and casings. In the early days, steel shells were mostly chosen as shell materials, and aluminum shells are the dominant ones at this stage. The design of the cylindrical battery as car battery types is basically exactly the same as the AA battery that is seen in daily life.
Tesla is using this battery shape, the production process is very mature, and the performance is relatively stable. The reason why Tesla chose this battery shape as car battery types is mainly because it will leave some pores between the batteries when it is packaged. These pores can provide a space for the battery to dissipate heat, effectively preventing the battery from overheating. However, this kind of battery is relatively heavy because it uses a metal case, and the energy density of a single battery is not very high.
② Square battery
Square batteries are also common, usually referring to aluminum or steel square batteries. The structure of the square battery is relatively simple, the weight of the overall accessories is light, the relative energy density is relatively high, and the power supply capacity is very strong. The plasticity of the square battery in car battery types will be stronger, and it can be customized according to the specific needs of the carried product, but this also leads to its different sizes, and there is no clear standard for manufacturing.
Whether it is the manufacturing process or application standards, there is no clear standard division like cylindrical batteries. The disadvantage is that it is difficult to unify the standards, and the battery models of each car are not the same, which can easily cause confusion in the market.
③ Pouch battery
The pouch battery is a battery that uses aluminum-plastic film as the packaging material, and needs to be heat-packed. The basic structure of the pouch lithium battery is similar to that of the cylinder and the square, except that the pouch lithium battery is a liquid lithium-ion battery covered with a polymer shell. The structure adopts aluminum-plastic film packaging, which generally consists of three layers.
Among the car battery types, the packaging material and structure of pouch batteries give them a series of advantages. For example, the safety performance is good, and the structure of the pouch battery is packaged with aluminum-plastic film. When a safety problem occurs, the pouch battery will generally explode with gas, instead of exploding like a steel or aluminum case battery. Light weight, can reduce the burden on the car.
The design is flexible, and the shape of the shape can be changed at will. The disadvantages are that the consistency is poor, the cost is high, and liquid leakage is prone to occur. Moreover, the aluminum-plastic film looks very simple, but how to combine the three layers of materials evenly and firmly is not so easy. And now good quality aluminum-plastic film is basically dependent on imports.
To a certain extent, different car battery types are not strictly good or bad. They conform to the car battery voltage, have their own advantages and disadvantages, and can play their own advantages in different use environments. In recent years, the new energy trend of the global automobile industry has been strong, and power batteries, which are constantly iterative in technology, are becoming a booster for industrial transformation. At the same time, it is also a top priority to vigorously improve the charging facilities for new energy vehicles.