▎ 摘　　要

NOVELTY - A composite conductive agent comprises single-walled or small-walled carbon nanotubes and graphene nanosheets. The single-wall or small-walled carbon nanotubes have specific surface area of 200-1500 m2/g, pipe diameter of 1-10 nm, and tube length of more than 5 mu m. The graphene nanosheets have diameter of is 0.2-2 mu m, specific surface area of less than 1800 m2/g and thickness of less than 2 nm. USE - Composite conductive agent is used for preparing positive and negative plate for lithium ion battery (all claimed). ADVANTAGE - The composite conductive agent has low temperature discharge, and high-temperature storage property, and cycle performance. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) preparation of composite conductive agent, which involves adding single-walled or small-walled carbon nanotubes, graphene nanosheets and dispersants to the diluent, and completely dispersing using dispersant chosen from polyvinylpyrrolidone, polyvinylidene fluoride and sodium carboxymethyl cellulose. The diluent is N-methylpyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide or water. The composite conductive agent component comprises 0.05-5 pts. wt. single-wall or small-wall carbon nanotubes, 0.05-5 pts. wt. graphene nanoplatelets, 0.1-1 pt. wt. dispersant and 100 pts. wt. diluent; (2) lithium-ion battery positive plate, which has a positive electrode current collector and an active coating layer coated on the surface of the positive electrode current collector. The active coating component comprises 90-110 pts. wt. positive electrode active material, 0.1-2 pts. wt. composite conductive agent, 0.1-2 pts. wt. binder (A) and 30-50 pts. wt. solvent; (3) preparation of lithium-ion battery positive plate; (4) lithium-ion battery negative plate, which comprises negative current collector and active coating formed on the surface of the negative current collector. The active coating components comprise 90-110 pts. wt. negative electrode active material, 0.1-2 pts. wt. composite conductive agent, 0.1-2 pts. wt. thickener, 0.2-4 pts. wt. binder (B) and 80-120 pts. wt. water; (5) preparation of lithium-ion battery negative plate; and (6) lithium ion battery, which has negative plate, positive plate and electrolyte.