Planetary Centrifugal Mixer Applications

The Benefits of Using a Planetary Centrifugal Mixer
in Blending a Battery Slurry

Over the past several years, many studies about battery slurries been released that demonstrate the importance of achieving a uniform and precise blend of slurry materials for the longevity and performance of the resulting batteries. A slurry is a semiliquid mixture, which typically consists of fine particles suspended in water. In terms of battery manufacturing, the respective energy storage abilities of different types of battery slurry formulations have been assessed over time. Lithium battery slurry uses a mixture of solid active materials, conductive additions and liquid electrolyte as the electrode. Polymer and solvent binder material help keep the slurry together. A study published in the IOP Conference Series: Materials Science and Engineering journal proved that the proportion of conductive matter to other active materials has significant influence on the conductivity and electrochemical performance of the lithium slurry electrode. This is also true for different types of battery slurries.

For instance, a solid-state battery uses a slurry that contains solid electrodes and a solid electrolyte, instead of liquid electrolytes found in lithium-ion batteries. Solid-state batteries have a strong record of safety under stressful conditions, which makes them an ideal candidate for use in electric vehicles. Sheet-type solid state batteries are of particular interest to many industries; these batteries are essentially stackable compact sheets with high cell-based energy density. A study published in the Journal of Power Sources attempted to refine the sheet-battery manufacturing process in order to accomplish better mass fabrication. Due to the level of precision required, battery slurry preparation can be a tricky process without the right tools for the job. The researchers in the study dispersed a mixture of LiNi1/3Co1/3Mn1/3O2 (NCM) in n-decane, toluene, or 1,2-dichloroethane as solvents, using a Mazerustar KK-250S model planetary mixer. They discovered that high fabrication pressure lead to the pulverization and cracking of NCM and LPS in the positive composite electrode, resulting in a decrease of the discharge capacity. A slight change in just one variable can dramatically affect the grade of a battery slurry.

Because slurries have a very specific consistency, the mixing process that they undergo is crucial to their overall performance. Studies that have assessed battery slurries tend to use planetary centrifugal mixers to blend materials due to the specific mixing and homogenizing power of these machines, which allow precise results to be attained each time. Due to their full automation, planetary centrifugal mixers consistently mix, disperse and degas materials efficiently. Torrey Hills Technologies offers two distinct lines of planetary centrifugal mixers with contactless operation: their own innovative SI-PM series, as well as paste mixers by Mazerustar. Both lines feature vacuum and non-vacuum models. While a non-vacuum model does a great job eliminating air bubbles, a vacuum model can remove air bubbles at a submicron-level from battery slurries.

Sources

  • https://www.sciencedirect.com/science/article/abs/pii/S0378775318310486
  • https://iopscience.iop.org/article/10.1088/1757-899X/207/1/012076
  • https://www.jstage.jst.go.jp/article/jcersj2/125/5/125_16321/_article/-char/ja/