Ultrasonic Battery slurry dispersion machine

What is the Ultrasonic Battery slurry dispersion machine?

Battery slurry is a key material used in battery manufacturing, usually composed of active materials, binders, conductive agents and solvents. The following is a detailed introduction to its composition and function:

Active material: It is the main substance in the battery where electrochemical reactions occur, and determines key indicators such as battery capacity, energy density and charge and discharge performance. For example, in lithium-ion batteries, commonly used active materials include lithium cobalt oxide, lithium iron phosphate, ternary materials (such as nickel cobalt manganese oxide), etc. as positive electrode active materials, while negative electrode active materials are usually graphite, etc.

Binder: Its function is to bind particles such as active materials and conductive agents together to form an electrode structure with certain strength and stability, and enable the electrode to be firmly attached to the current collector. Common binders include polyvinylidene fluoride (PVDF), sodium carboxymethyl cellulose (CMC), styrene butadiene rubber (SBR), etc.

Conductive agent: In order to improve the conductivity of the electrode, a conductive agent needs to be added. It can form a conductive network between the active material particles, reduce the resistance of the electrode, and enable electrons to be quickly transmitted in the electrode, thereby improving the battery's charge and discharge efficiency and rate performance. Commonly used conductive agents include carbon black, graphene, carbon nanotubes, etc.

Solvent: Mainly used to dissolve binders and disperse other components to give the slurry good fluidity and coating properties. In the preparation of battery slurry, the solvent can help the components to mix evenly and form a stable suspension. When the slurry is applied to the current collector, the solvent will evaporate, leaving solid electrode materials. Commonly used solvents in lithium-ion battery slurries include N-methylpyrrolidone (NMP), etc.

The performance of battery slurry has a crucial impact on the overall performance and quality of the battery. Parameters such as slurry uniformity, viscosity, solid content, etc. need to be strictly controlled to ensure the consistency and stability of the electrode, thereby improving the performance, life and safety of the battery.

The ultrasonic machine is used to disperse positive and negative electrode materials, nano-electrode materials, and induce crystallization of lithium batteries. It improves the uniformity of slurry, shortens the time of traditional slurry stirring, improves slurry making efficiency, and reduces costs. After making the battery cell, the internal resistance of the product is reduced, the consistency is improved, the cycle life is long, and the capacity retention rate is high. It is more significant in the mixture with nano-level materials, effectively breaking up the agglomerates, and the storage time is long and stable.

Ultrasonic waves can be used to disperse battery slurry for the following reasons:

Cavitation: When ultrasonic waves propagate in liquid, cavitation occurs. When the sound pressure of ultrasonic waves reaches a certain level, tiny bubbles in the liquid will expand rapidly in the negative pressure stage and then collapse sharply in the positive pressure stage. This instantaneous collapse of bubbles will produce local high temperature, high pressure, strong shock waves and microjets, which can effectively break up the agglomerates in the slurry, evenly disperse the particles in the liquid, prevent particle precipitation and agglomeration, and improve the stability of the slurry.

Mechanical vibration: The high-frequency vibration of ultrasonic waves can subject the particles in the battery slurry to periodic mechanical forces. This mechanical force can overcome the interaction forces such as van der Waals force and electrostatic attraction between particles, and disperse the agglomerated particles. At the same time, vibration can also promote the mixing of the components in the slurry, so that additives are evenly distributed in the slurry, which is conducive to improving the consistency and performance of the slurry.
Accelerate the mass transfer process: Ultrasonic waves can enhance the mass transfer process in liquids. In battery slurry, it can accelerate the interaction between solvent molecules and particle surfaces, promote the wetting and penetration of solvent into particles, and make particles more easily surrounded by dispersion medium, thereby improving the dispersion effect. In addition, the acceleration of mass transfer process is also conducive to chemical reactions. For example, in the slurry preparation process, if some additives are involved in dissolution or chemical reactions, ultrasound can make these processes more complete and uniform.