Lithium cobalt oxide is an inorganic compound commonly used as the positive electrode material in lithium-ion batteries. A lithium-ion battery that uses lithium cobalt oxide as its positive electrode material is called a lithium cobalt oxide battery.
Advantages of lithium cobalt oxide batteries:
Lithium cobalt oxide batteries are lithium-ion batteries with superior electrochemical performance, exhibiting a capacity decay rate of less than 0.05%, an initial discharge specific capacity greater than 135 mAh/g, stable performance, good consistency, ease of synthesis, and good safety. The operating temperature range for lithium cobalt oxide batteries is -20℃ to 55℃.
Disadvantages of lithium cobalt oxide batteries:
1. Cobalt is expensive and only produced in parts of Africa, which poses risks of regional disputes and price fluctuations; 2. Due to the rock salt structure of LiCoO2, only about 50% of the original lithium can be removed. This means that the basic structure will be damaged during overcharging, resulting in the loss of reversible charge-discharge cycles. This makes lithium cobalt oxide batteries a potential safety hazard due to overcharging, requiring additional circuit protection boards; 3. The thermal stability and toxicity indicators are not ideal, and the countermeasures are relatively complex.
The key technology in the fabrication of lithium cobalt oxide batteries lies in the manufacturing of lithium powder:
Lithium cobalt oxide batteries use a liquid-phase synthesis process, in which lithium salt and cobalt salt are dissolved in polyvinyl alcohol and polyethylene glycol solutions, respectively. The mixed solution is heated and concentrated into a gel, and the gel is calcined at high temperature to form powder, which is then ground and sieved to obtain lithium cobalt oxide powder.
Applications of lithium cobalt oxide batteries:
Lithium cobalt oxide batteries have become the mainstream lithium-ion battery due to their ease of synthesis, high voltage platform, moderate specific energy, and especially excellent cycle performance. However, the insufficient reserves of cobalt and the challenges of overcoming its toxicity and overcharging during preparation have increased the cost of lithium cobalt oxide batteries. Therefore, the market for lithium cobalt oxide is generally positioned for portable devices rather than large power equipment.
