What are the requirements of lithium-ion batteries for cathode materials?

The performance of the lithium-ion battery cathode material directly affects the performance of the lithium-ion battery, and its cost also directly determines the cost of the battery. At present, the positive electrode materials that have been successfully developed and applied mainly include lithium cobaltate, lithium iron phosphate, lithium manganate, ternary materials nickel-cobalt lithium manganate (NCM) and nickel-cobalt lithium aluminate (NCA).
The basic requirements of lithium-ion batteries for cathode materials:
First, the potential of the material itself is high, so that it can form a large potential difference with the negative electrode material, resulting in a cell design with high energy density; at the same time, the insertion and extraction of charged ions have little effect on the electrode potential, so there will be no excessive voltage fluctuations during the charging and discharging process, and will not adversely affect other electrical components in the system.
Second, the material contains high lithium content and the intercalation and deintercalation of lithium-ion batteries are reversible. This is the premise of high capacity. Some cathode materials have a high theoretical capacity, but half of the lithium ions lose their activity after the first intercalation. Such materials cannot be put into commercial use.
Third, the diffusion coefficient of lithium ions is large, the movement of lithium ions in the material is faster, and the ability of intercalation and deintercalation is strong. It is a factor that affects the internal resistance of the battery cell and is also a factor that affects the power characteristics.
Fourth, the material has a large specific surface area and a large number of lithium intercalation sites. The surface area is large, and the intercalation channel of lithium ions is relatively short, so intercalation and deintercalation are easier. While the channel is shallow, the lithium insertion position should be sufficient.
Fifth, the compatibility and thermal stability with the electrolyte are good, which is for safety considerations.
Sixth, the material is easy to obtain and has good processing performance. The cost is low, the material is easy to process into electrodes, and the electrode structure is stable, which are favorable conditions for the popularization and application of cathode materials for lithium-ion batteries.