Porous hard carbon negative electrode material based on asphalt as well as preparation method and application of porous hard carbon negative electrode material

The invention belongs to the field of electrochemistry, and particularly relates to an asphalt-based porous hard carbon negative electrode material as well as a preparation method and application thereof. Firstly, asphalt powder is modified with a cross-linking agent or a modifying agent, the disordering degree in the carbonization process is improved, then uniform distribution of nano asphalt particles and the modifying agent is achieved through spray drying and secondary granulation, and the disordered state of asphalt in the sintering process is improved; meanwhile, the uniform pore-forming agent in the balling process forms a multi-stage pore channel structure in the acidizing and washing process; and finally, carbonizing after high-temperature pre-oxidation is matched with a strong acid oxidation microcrystal interface to enhance the repulsive force between microcrystals, so that the aim of increasing the interlayer spacing of the hard carbon microcrystals is fulfilled. The porous hard carbon negative el