SDK Starts Volume Production of LIB Anode Binder
Showa Denko K.K. (SDK) has started volume production of “PolysolTM LB Series” water-based anode binder for lithium ion batteries (LIBs) at its Tatsuno Plant in Tatsuno City, Hyogo Prefecture.
The product is a water-based emulsion containing acrylic synthetic resin particles, ensuring lower environmental impact at the time of production compared with solvent-based binders. It provides such advantages as low electrical resistance, good temperature characteristics, and good adhesion to anode collectors, thereby contributing toward extending the life and increasing the capacity of LIBs. Having improved the product properties based on the results of sample evaluation by potential customers, SDK has decided to sell the product on a commercial scale.
Development of LIB technology is being accelerated. This is because small LIBs for high-performance smartphones and tablets need to become thinner and have higher capacity. Also, large LIBs for industrial/home storage batteries, electric vehicles and hybrid cars should have high capacity, long life, and good durability under severe working conditions.
In addition to the four major LIB components (cathode material, anode material, separator, and electrolyte), binders are a target of technological development as they significantly influence the performance of LIBs.
A binder causes cathode/anode active materials (for release and intake of lithium ions) to stick together. It also causes additives to stick together, and active materials to adhere to collectors. While styrene-butadiene rubber (SBR) is mainly used in binders, it has a problem of deterioration at high/low temperatures. Compared with SBR, “PolysolTM LB Series” can improve temperature characteristics by around 10%, in terms of the maintenance of capacity at the time of charge/discharge after preservation at a high temperature (60ºC) and in service capacity at a low temperature (-20 ºC).
Furthermore, it exhibits high binding property with addition of a small amount due to its high dispersibility, and increases adhesion to anode collectors (made of copper) by 1.5 times, enabling reductions in inner electrical resistance. Thus, “PolysolTM LB Series” will contribute toward extending the life and increasing the capacity of LIBs.
The Showa Denko Group will continue to fully utilize its proprietary inorganic, aluminum and organic chemical technologies to improve the performance of its LIB-related products, including anode material, additive in anodes/cathodes, packaging material, and binder. At the same time, the Group will provide total solutions to customers, making proposals on ways of combining various components to better meet their requirements.