Jet mill has become the first choice for the preparation of cathode materials

Many kinds of equipment can be used to crush the positive electrode material, such as: grinder, pin sand mill, jet mill, etc. Compared with other crushing equipment, the average particle size of the material processed by the jet mill is fine, the particle size distribution is narrower, the particle surface is smooth, the particle shape is regular, the purity is high, the activity is high, and the dispersion is good, which fully meets the preparation requirements of electrode materials. Therefore, jet mills are widely used.

At present, the preparation of cathode materials using jet mills has become the industry’s first choice. Jet mill is a kind of equipment that uses high-speed airflow to achieve ultra-fine grinding of dry materials. It consists of a crushing nozzle, a grading rotor, a screw feeder and so on. The material enters the crushing chamber through the screw feeder, and the compressed air is jetted into the crushing chamber at a high speed through a specially configured supersonic nozzle. The material is accelerated in the supersonic jet and repeatedly impacts and collides at the intersection of the nozzles to achieve crushing. The pulverized material enters the classification chamber with the ascending airflow. Due to the high-speed rotation of the grading rotor, the particles are subjected to the centrifugal force generated by the grading rotor and the centripetal force generated by the viscous action of the airflow. When the centrifugal force is greater than the centripetal force, the coarse particles above the grading diameter return to be crushed. The chamber continues to be impacted and crushed, and the fine particles below the classification diameter enter the cyclone separator and collector with the air flow for collection, and the gas is discharged by the induced draft fan.

There are many advantages of using a jet mill to prepare cathode materials, which can be summarized as follows:

1.  The jet mill has the ability to shape, the finished particles have excellent morphology, and can obtain spherical (potato-like) particles.

2.  Narrow particle size distribution and high tap density of the finished product.

3.  The over-crushing is low, and the finished product rate can reach 75%-95% or more.

4.  The inside of the equipment can be lined with wear-resistant materials, and the finished product has high purity and low equipment wear.

5.  The air flow classifier adopts frequency conversion adjustment, which can be adjusted arbitrarily between 0.5μm and 100μm.

6.  The equipment runs stably, and there is no difference or change when it is turned on continuously for a long time.

7.  Fully enclosed negative pressure operation, automatic control, low noise and no dust pollution.

The jet mill for positive electrode material uses precision ceramics and polyurethane lining, which can 100% prevent metal pollution caused by the crushing process of materials and ensure the purity of crushed products. It is especially suitable for electronic materials that require extremely high iron content, such as lithium cobaltate, lithium manganate, lithium iron phosphate, lithium iron phosphate, ternary materials, cobalt tetroxide, lithium carbonate, lithium nickel cobaltate and other battery cathode materials.