Preparation method of nickel selenide supercapacitor based on space charge mechanism energy storage

The embodiment of the invention discloses a preparation method of a nickel selenide supercapacitor based on a space charge mechanism. The graphene coated hollow nanosphere morphology nickel selenide is prepared by using a hydrothermal method. The material is coated on a copper foil to prepare an electrode, metal lithium, sodium or a lithium and sodium metal compound is used as a counter electrode, the electrode material is stabilized after several cycles of charging and discharging, and then the electrode material is discharged to 0V, so that the interior of the electrode material is fully filled with a space charge region. And then the pole piece is detached from the vacuum glove, activated carbon is used as a counter electrode, a proper voltage interval is scanned to avoid oxidation potential, and the supercapacitor is manufactured. The supercapacitor can well avoid the defect of poor cycle stability caused by huge volume deformation caused by oxidation reduction of nickel selenide, and an energy storage de