▎ 摘　　要

NOVELTY - The cathode pole element has an interface layer that is compounded on the negative electrode current collector surface and the active material layer that is compounded in the interface layer. The interface layer comprises a polymer substrate comprising polymer A and polymer B and a conductive agent A embedded in the polymer substrate. The polymer A comprises at least one of polyvinylidene fluoride, polytetrafluoroethylene, sodium carboxymethyl cellulose and polyvinyl alcohol. The conductive agent A comprises at least one of Ketjen black, graphene, acetylene black, carbon fiber, carbon nanotube, and conductive graphite. The polymer B comprises non-polar high molecular polymer styrene-butadiene latex. The active material layer includes a sodium-ion battery active material, a conductive agent B and a binder. USE - Cathode pole element of sodium ion battery (claimed) used in mobile phone, notebook computer, flat computer and other electronic device, electric automobile and hybrid vehicle. ADVANTAGE - The cathode has a small resistance and a higher specific capacity, as the cathode of the sodium ion battery, it can exhibit better electrochemical performance. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) a preparation method of the sodium ion battery cathode pole element; and (2) a sodium ion battery.