Sodium-ion battery with high specific capacity, porous Yolk-shell structure carbon/tin material thereof and preparation method

The invention discloses a sodium-ion battery with high specific capacity, which comprises a positive plate, a negative plate, a membrane and an electrolyte solution, wherein the negative plate is a metal sodium sheet, and the positive plate is made by mixing a porous Yolk-shell structure carbon/tin material, a conductive agent and a binding agent at a mass ratio of 8:(1-2):(1-2), then adding N-methyl pyrrolidone NMP, performing stirring uniformly, coating an aluminum foil, and performing vacuum drying. The invention further discloses the porous Yolk-shell structure carbon/tin material used for the sodium-ion battery with high specific capacity, and a preparation method. The porous Yolk-shell structure carbon/tin material is prepared by taking resorcin, a polyoxyethylene-polyoxypropylene-polyoxyethylene triblock copolymer, stannic oxide particles and formaldehyde as raw materials, and adopting a coating-carbothermic reduction method. Compared with the prior art, the porous Yolk-shell structure carbon/tin mater