Preparation method of expanded graphite inlaid selenide negative electrode material for sodium ion battery

The invention belongs to the technical field of battery materials, and particularly relates to a method for preparing a sodium ion battery negative electrode material with expanded graphite inlaid with selenide by adopting a liquid phase reaction. According to the method for preparing the transition metal selenide through coprecipitation, the transition metal selenide which cannot be obtained through a common solid-phase/gas-phase reaction and has specific morphology and atomic proportion can be prepared, and the expanded graphite inlaid with the selenide and obtained through subsequent preparation is a very ideal sodium-ion battery negative electrode material; moreover, the transition metal salt and the natural crystalline flake graphite which are easy to obtain are used for preparing the product, the technological process is simple, time consumption is low, energy consumption is low, the product performance is good, and the method is particularly suitable for industrial production. 本发明属于电池材料技术领域，具体涉及一种采用液相反