▎ 摘　　要

NOVELTY - Cathode sheet comprises a protective layer provided on the surface of a current collector. The protective layer comprises carbon material doped with nitrogen element. The content of the nitrogen element is gradually reduced along the direction away from the current collector in the protective layer. The carbon material comprises carbon nano-fiber, carbon nano-tube, carbon nano-rod and graphene. The carbon nanofiber is carbon nanofiber. The protective layer comprises A surface close to current collector and B surface far away from the current collector. USE - The cathode sheet is useful in lithium battery (claimed), lithium ion battery, and for a lead-acid battery. ADVANTAGE - The sheet: can uniformly deposit lithium ion in the protective layer of the cathode sheet, so as to inhibit the lithium dendritic crystal to continuously grow, and avoid the short circuit of the battery. The lithium battery has excellent coulomb efficiency and excellent cycle life. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for lithium battery.