Energy storage device

The invention discloses an energy storage device which is characterized in that the structure of the energy storage device is designed on the basis of a reverse electrodialysis technology, so that transmission ions can be transmitted in a first structure and a second structure to form an internal loop; meanwhile, due to the existence of the oxidizing substance and the reducing substance, when the oxidizing substance is subjected to the reduction reaction and the reducing substance is subjected to the oxidation reaction, an oxidation-reduction potential difference can be formed, and due to the fact that the oxidation reaction and the reduction reaction are continuously carried out, the oxidation-reduction potential difference can be continuously provided; therefore, when the electric signal is output outwards at least based on the oxidation-reduction potential difference, continuous high output of the electric signal can be realized, so that the energy storage device has high output power density and good outp