Knowledge about Lithium Cobalt Oxide Batteries

The core materials of lithium cobalt oxide batteries are cobalt and lithium. The cycle performance of lithium cobalt oxide lithium metal batteries is closely related to these materials. The following section will delve into the advantages and disadvantages of their electrochemical performance by examining the working principle of lithium cobalt oxide batteries. Lithium cobalt oxide, with the chemical formula LiCoO2, is an inorganic compound commonly used as the positive electrode material in lithium-ion batteries.

1. Advantages of Lithium Cobalt Oxide Batteries:

(1) Superior electrochemical performance: Average capacity decay per cycle <0.05%, initial discharge specific capacity >135mAh/g, 3.6V initial discharge plateau ratio >85%.

(2) Excellent processing performance.

(3) High tap density, which helps improve the battery's volumetric specific capacity.

(4) Stable product performance and good consistency.

(5) Advantages include high operating voltage, stable discharge, high specific energy, and good cycle performance.

(6) Suitable for high-flow discharge and lithium-ion insertion and extraction, making it a pioneer in lithium-ion batteries.

2. Disadvantages of Lithium Cobalt Oxide (LiCoO2):

(1) The actual capacity of LiCoO2 is approximately 140 mA/g, only about 50% of the theoretical capacity (274 mA/g).

(2) During repeated charging and discharging, the repeated insertion and extraction of lithium ions alters the structure of the active material after multiple contractions and expansions, leading to increased internal resistance and decreased capacity in LiCoO2.

Reactions occurring during the charging and discharging process of LiCoO2:

Reaction during charging:

Positive electrode: LiCoO2 = Li1-xCoO2 + xLi+ + xe-

Negative electrode: 6C + xLi+ + xe- = LixC6

Reaction during discharging:

Positive electrode: Li1-xCoO2 + xLi+ + xe- = LiCoO2

Negative electrode: LixC6 = 6C + xLi+ + xe-

Lithium cobalt oxide batteries have a stable structure, high specific capacity, and outstanding overall performance, but they have poor safety and very high cost. They are mainly used in small and medium-sized cells and are widely used in small electronic devices such as laptops, mobile phones, and MP3/4 players. The nominal voltage is 3.7V.