Cathodes for high voltage lithium-ion secondary battery and dry method for manufacture of same

• Main Authors: LI, WEI-KANG, KOUNTZ, DENNIS J, WATERS, CRYSTAL K, MENG, YING SHIRLEY, GOULD, BENJAMIN, SICHLER, ALLISON, YAO, WEI-LIANG, ZHANG, MING-HAO
• Format: Patent
• Language: Chinese; English
• Published: 16.05.2023
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRICITY; PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSIONOF CHEMICAL INTO ELECTRICAL ENERGY

A cathode for a high voltage lithium-ion secondary battery is described, including: an electrode layer having an electrode composition containing cathode active particles, fluoropolymer binder and conductive carbon. The cathode active particles are high voltage lithium transition metal oxides, the fluoropolymer binder is a fibrillated tetrafluoroethylene polymer having high melt creep viscosity, and the conductive carbon is carbon fibers having a specific surface area of about 50 m2/g or less. The carbon fibers and the fluoropolymer binder form a conducting structural web electronically connecting the cathode active particles, enabling electronic conductivity through the electrode layer. The electrode layer is adhered to a current collector comprising aluminum having surface roughness and substantially no carbon surface coating other than the conductive carbon of the electrode layer. Further described is a dry binder process to fabricate such cathodes, and the utility of such cathodes in high voltage lithium-