CATHODES FOR HIGH VOLTAGE LITHIUM-ION SECONDARY BATTERY AND DRY METHOD FOR MANUFACTURE OF SAME

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-ion secondary batteries.