Preparation method of metal-salt-coated carbon nano-material

The invention discloses a preparation method of a metal-salt-coated carbon nano-material, comprising: first, ultrasonically dispersing carbon nano-material, an ionic surfactant and water to obtain stable uniform suspension; second, adding metal salt A solution under high-speed stirring, dropwise adding metal salt B solution slowly which may be subjected to precipitation reaction with the metal salt A solution; third, centrifuging, drying, and performing other steps to obtain core-shell structures under different coating levels. The low conductivity of metal salts and high conductivity of carbon material are combined to synthesize core-shell structured dielectric material for the metal-salt-coated carbon nano-material, the charging-discharging speed is high, discharging power is high, and the material has a promising application prospect in the fields of electric vehicles, power systems, laser weapons and the like, and a novel preparation method having good operational simplicity, good process stability, low cost and good material structure controllability is provided.