High-safety composite electrode, sodium ion battery and battery preparation method

The invention discloses a high-safety composite electrode, a sodium ion battery and a battery preparation method, and relates to the technical field of sodium ion batteries. Comprising a polymer layer, metal layers coated on two opposite sides of the polymer layer, two conductive layers coated on the upper and lower surfaces of the metal layers, a negative active material layer and a positive active material layer respectively coated on the outer surfaces of the two conductive layers, and an insulating layer arranged at the edge of the positive active material layer. The polymer layer has excellent electronic insulativity, the density of the polymer layer is smaller than that of a traditional metal current collector, and the weight of the current collector can be reduced, so that the energy density is improved; the metal layer plays a role in collecting micro-current in the working process of the battery, so that the safety performance is improved; one side of the whole electrode plate serves as a negative el