What is the material dispersion problem of lithium iron phosphate batteries? How to solve?

Due to the low diffusion coefficient and poor conductivity of lithium ions, the current practice of lithium iron phosphate batteries is to make their particles small, or even make them into nano series, and improve their charging and discharging speed by shortening the migration path of LI+ and electrons (theoretically, the migration time is inversely proportional to the square of the migration path). But this brings a series of difficulties to the lithium battery processing.

For example, the most common problem is the dispersion of materials.

Pulping is one of the most critical processes in the battery production process. Its core task is to evenly mix the active material, conductive agent, binder and other materials, so that the material performance can be better played. To mix well, first you need to be able to disperse. When the particles decrease, the corresponding specific surface energy and surface energy increase, and the tendency of interparticle polymerization increase. The greater the energy required to overcome surface energy dispersion. Mechanical stirring is commonly used now. The energy distribution of mechanical stirring is uneven. Only in a certain area, the shear strength is large enough and the energy is high enough to separate the aggregated particles. To improve the dispersing ability, one is to optimize the structure of the stirring equipment and increase the space proportion of the effective dispersing area without changing the maximum shear speed. One is to increase the mixing power (increase the mixing speed), increase the shear speed, the corresponding effective dispersion space will also increase. The former is equipment on the problem, how much room for improvement, coating online do not comment. In the latter case, the lifting space is limited, because the shear speed is up to a certain limit, which will cause damage to the material and damage to the particles.

A more effective method is to use ultrasonic dispersing technology. Only ultrasound equipment price is higher, earlier contact, its price and the import of Japanese mechanical stirrer. Ultrasonic dispersion process time is short, the overall energy consumption is reduced, pulp dispersion effect is good, effectively delay the material particles aggregation and stability is greatly improved.

In addition, you can through the use of dispersants to improve the dispersion effect.

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