High-power battery type capacitor and preparation method thereof

The invention discloses a high-power battery type capacitor and a preparation method thereof.According to the method, a lithium nickel manganese oxide/activated carbon composite material and graphene/carbon nanotubes are compounded again through ultrasonic treatment, a 3D lithium nickel manganese oxide/activated carbon composite positive electrode material of a three-dimensional network conductive structure is prepared, the diffusion rate of lithium ions is increased, and the performance of the capacitor is improved; the resistance and polarization of the capacitor in the charging/discharging process are greatly reduced; the porous nanoflower niobium pentoxide negative electrode material is prepared by combining a solvothermal method and a high-temperature solid-phase method, and the porous nanoflower structure can further promote rapid transmission of lithium ions in the electrode; and the assembled battery type capacitor has relatively high energy density and power density and stable product cycle performan