Bismuth-carbon negative electrode material for wide-temperature-range sodium battery as well as preparation method and application of bismuth-carbon negative electrode material

The invention relates to the technical field of sodium-ion batteries, in particular to a bismuth-carbon negative electrode material for a wide-temperature-range sodium-ion battery as well as a preparation method and application of the bismuth-carbon negative electrode material. The preparation method comprises the following steps: uniformly mixing and stirring a reducing agent, a shape adjusting agent and water, adding bismuth salt for hydrothermal reaction, cooling, adding a carbon source into the solution, uniformly stirring, carrying out spray drying on the obtained solution, carbonizing the obtained powder material in an inert atmosphere, and screening the cooled material after carbonization to obtain the bismuth carbon negative electrode material. The bismuth carbon negative electrode material prepared by the invention forms a passive film, the high-temperature cycle performance of the obtained sodium ion battery is better, and the battery efficiency can still reach 80% or above after 100 cycles at the h