General description
Lithium-ion batteries are widely used for portable devices and electric vehicles because of their high energy density and long cycle life. One of the key components of lithium-ion batteries is the cathode material, which determines the capacity and voltage of the battery. Cathode materials are usually oxides of lithium and one or more transition metals, such as cobalt, nickel, manganese, iron, or aluminum. Different cathode materials have different advantages and disadvantages in terms of cost, performance, safety, and environmental impact.
Cathode materials - LFP
Lithium iron phosphate (LiFePO4) is an inorganic compound that is insoluble in water and has a gray, red-grey, brown or black color. It is a natural mineral of the olivine family and has a low cost, high safety, low toxicity, long cycle life and excellent thermal stability. It is suitable for applications that require high power and safety, such as electric vehicles and grid storage. However, lithium iron phosphate materials also have some drawbacks, such as low electrical conductivity and low energy density compared to other lithium-ion battery types. Therefore, various methods have been developed to improve the performance of lithium iron phosphate materials, such as reducing the particle size, coating them with conductive materials or doping them with other elements. It has a moderate specific capacity (about 170 mAh/g) and a low operating voltage (about 3.2 V).
Cathode materials - NMC
Lithium nickel cobalt manganese oxide (NMC): This is a widely used cathode material for various applications, such as electric vehicles, power tools, and grid storage. It has a high specific capacity (about 200 mAh/g) and a high operating voltage (about 3.7 V). It also has a good balance between cost, performance, safety, and environmental impact. However, it still faces challenges such as cobalt scarcity, nickel toxicity, and thermal instability. To overcome these challenges, various strategies have been developed to optimize the composition, morphology, and surface modification of NMC.
Notes
Data from Delta Analysis and BAN.
To download the data, click the cloud in the right corner at the bottom of the figure.