What are the categories of cathode materials for lithium-ion batteries?
The power battery (lithium-ion battery) is the heart of a new energy vehicle, generally accounting for about 40% of its cost. The cathode material is the core of the power battery, also accounting for about 40% of its cost.
The choice of cathode material directly determines the performance of the battery. Because cathode materials have a significant impact on battery performance, many researchers are dedicated to developing cathode materials with higher performance, such as lithium nickel oxide, lithium cobalt oxide, and lithium titanate.
1. Lithium Nickel Oxide. The main representative of lithium nickel oxide is lithium nickel oxide. Its product characteristics are similar to those of nickel cobalt oxide, but its price is lower. Due to its high energy density, which can reach 274 mAh/g, it is a relatively ideal high-energy-density lithium-ion battery cathode material. However, its safety performance is too poor and its cycle life is relatively low. Therefore, there are not many manufacturers currently using lithium nickel oxide as a cathode material for lithium-ion batteries.
2. Lithium cobalt oxide. The main representative of lithium cobalt oxide is lithium cobalt oxide, which has five high characteristics: high energy density, high price, high power, high commercialization, and high cycle life. However, its shortcomings are also obvious. my country is severely lacking in cobalt salts and needs to import them.
3. Lithium Titanium Oxide. A typical example of lithium titanium oxide is lithium titanate, in which Zhuhai Yinlong dominates the market. The advantage of lithium titanate is fast charging, while its disadvantage is low energy density, requiring charging after a period of use. Another advantage is safety, and a third advantage is its ability to withstand up to 20,000 cycles.
4. Nickel-cobalt multi-component oxides. These are the multi-component oxides we commonly refer to. The most common ones are lithium nickel cobalt manganese oxide and lithium nickel cobalt aluminum oxide. Lithium nickel cobalt manganese oxide is further divided into lithium nickel cobalt manganese oxide 111, lithium nickel cobalt manganese oxide 523, lithium nickel cobalt manganese oxide 622, and lithium nickel cobalt manganese oxide 811. However, lithium nickel cobalt aluminum oxide is not as widespread. This technology is mostly supplied by Panasonic to Tesla, with the ratio of lithium nickel cobalt aluminum oxide being 0.8:0.15:0.05.
5. Lithium manganese oxides. The main representatives of lithium manganese oxides are lithium manganese oxide and lithium permanganate. Resources are relatively abundant in my country, and the products are currently a research hotspot. Among them, LiMn2O4 has a high energy density, but its stability is greatly reduced, especially under high temperature conditions. LiMn2O4 is unstable, but its main advantages are obvious: the product is pollution-free and has good safety performance.
6. Lithium iron phosphate oxide. The main representative of lithium iron phosphate oxide is lithium iron phosphate. Its products have balanced performance in all aspects, are non-toxic and pollution-free, and have a cycle life of no less than 2,000 times. When used as a power source for passenger vehicles, its safety performance is at a high level.
In addition, lithium-ion battery cathode candidates can be mainly divided into three categories according to their structure: (1) layered LiMO2 (M=Co, Ni, Mn) cathode material; (2) spinel structure LiMn2O4 cathode material; (3) olivine structure LiFePO4 cathode material.
