The present invention discloses an energy storage device, which comprises a housing accommodating an electrolyte, a silicon-based electrode, a positive electrode plate, and a separation membrane, wherein the silicon-based electrode, the positive electrode plate, and the separation membrane are impregnated in the electrolyte, the separation membrane is arranged between the silicon-based electrode and the positive electrode plate, and the silicon-based electrode comprises an electric conduction base plate, a silicon layer provided with an atom doping layer on the surface and arranged on the electric conduction base plate, and an organic protection film layer plating and covering on the surface of the silicon layer having the atom doping layer. With application of the silicon-based electrode being subjected to the surface reforming treatment and plated with the organic protection film layer as the negative electrode of the energy storage device, the coulomb conversion efficiency can be increased, and the interface resistance can be reduced, such that the service life of the storage system can be increased. In addition, the sequence of the atom doping layer and the organic protection film layer can be replaced or the combination of the atom doping layer and the organic protection film layer can be adopted.