▎ 摘　　要

NOVELTY - Cathode sheet comprises a cathode current collector and a cathode active material layer coated on one side or both sides of the cathode current collector, and the cathode active material layer comprises a cathode active material, a conductive agent, binder and auxiliary, where the cathode active material includes a silicon-based material; the cathode active substance further comprises a carbon-based material, the carbon-based material is consisting of synthetic graphite, natural graphite, hard carbon, soft carbon, mesophase microsphere, fullerene, and/or graphene, where the auxiliary agent is polyphenylene based compound. USE - The cathode sheet is useful in a lithium ion battery (claimed) for notebook computer, mobile phone, camera and other consumer electronic products. ADVANTAGE - The cathode sheet can effectively improve the transport of lithium ions and electrons, form a solid interface film with a stable structure, suppress the volume change of the cathode sheet, and improve the cycle performance of the silicon cathode, specifically at room temperature cycle performance of the silicon cathode. The lithium ion battery has long service life, little self-discharge rate, is green and environmentally friendly. DETAILED DESCRIPTION - Cathode sheet comprises a cathode current collector and a cathode active material layer coated on one side or both sides of the cathode current collector, and the cathode active material layer comprises a cathode active material, a conductive agent, binder and auxiliary, where the cathode active material includes a silicon-based material; the cathode active substance further comprises a carbon-based material, the carbon-based material is consisting of synthetic graphite, natural graphite, hard carbon, soft carbon, mesophase microsphere, fullerene, and/or graphene, where the auxiliary agent is polyphenylene based compound of formula (R1-R-M-R'-R'1) (I). M=polyphenylene ether segment, polyethylene glycol segment, polyethylene dithiol segment, polycarbonate segment, polypropylene glycol segment or polysiloxane ether segment; R1 and R'1=end capping groups with C-C bond or C=C bond as an end group; and R and R'=linking groups.