Primer Surface Coating For High-Performance Silicon-Based Electrodes

• Main Authors: Yang Li, Dai Fang, Xiao Qiangfeng, Jimenez Niccolo, Cai Mei
• Format: Patent
• Language: English
• Published: 21.09.2017
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRICITY; PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSIONOF CHEMICAL INTO ELECTRICAL ENERGY

A negative electrode for an electrochemical cell (e.g., a lithium ion battery) is provided. The electrode has an active material that undergoes volumetric expansion during lithiation and delithiation, e.g., silicon-containing materials. The electrode has a current collector with an electrically conductive flexible surface primer coating disposed thereon. The primer coating comprises a polymer with a glass transition temperature of ≦85° C. and an electrically conductive particle. When assembled, the flexible surface primer coating serves to reduce strain at the interface between the active material and current collector. The primer coating and the electroactive material remain intact on the surface of the current collector after at least one cycle of lithium ion insertion and deinsertion in the electrode, thus minimizing or preventing charge capacity loss in the electrochemical cell. Methods for making such materials and using such coatings to minimize charge capacity fade in lithium ion electrochemical cells are likewise provided.