Production process of high nickel ternary positive electrode material

The positive electrode material of lithium-ion batteries is a part of the constituent materials of lithium-ion batteries. 

The main constituent materials of lithium-ion batteries include electrolytes, isolation materials, positive and negative electrode materials, etc. 

Positive electrode materials account for a large proportion because their performance directly affects the performance of lithium-ion batteries, 

and their cost directly determines the cost of the battery.

The main process flow of high nickel ternary positive electrode materials includes the following:

 1. lithiation mixing, 2. potting, 3. calcination, 4. crushing, 5. grading, 6. impurity removal, packaging, etc.

1. Lithiation and mixing: The main raw materials for ternary cathode materials include precursors and lithium sources. 

Mixing methods are generally divided into wet mixing and dry mixing. Dry mixing is commonly used in industry. 

The lithium source used for the high nickel ternary cathode material is battery grade lithium hydroxide monohydrate. 

During the mixing process, high nickel ternary materials require more uniform mixing and stricter control over humidity.

2. Bowl loading: The lithium source required for high nickel ternary cathode materials is well dispersed in the precursor. 

In order to prevent spontaneous agglomeration of the material during sintering, each bowl should not be loaded too much.

3. Calcination: Calcination process is the most core process in high nickel ternary materials, usually requiring pre firing and multiple sintering. 

Generally speaking, the higher the nickel content, the lower the sintering temperature. 

The actual sintering temperature of high nickel ternary materials is between 750~800 ℃, and pure oxygen assistance is required during the sintering process. 

The sintering process is repeated multiple times under oxygen rich conditions, and the calcination time is generally long, usually 20~25h. 

Therefore, its cost is much higher than that of ordinary ternary materials.

4. Crushing and Grading: High nickel ternary materials require particle crushing to the micrometer level after calcination, usually requiring three-stage crushing.

 At present, the commonly used crushing system in industry is the E-type crushing roller crushing air flow crushing, which obtains particle sizes of 1-20 μ m.

 After grading and screening, the industry generally selects D50=10 μ m particles as semi-finished particles.

5. Impurity removal and packaging: 

The semi-finished product of high nickel ternary material particles after classification needs to undergo impurity removal to remove metal impurities introduced in the process, 

mainly iron, which is usually removed by magnetic separation in industry. 

After impurity removal, the particles are vacuum packed to form the finished product of positive electrode material particles.