Patent attributes
An alkali metal ion capacitor that is capable of operating in a high-temperature environment at 85° C. The alkali metal ion capacitor is provided with: a positive electrode active material capable of adsorbing and desorbing alkali metal ions; a positive electrode binder for binding the positive electrode active material; a negative electrode active material capable of storing and releasing alkali metal ions; a negative electrode binder for binding the negative electrode active material; and an electrolytic solution that contains an organic solvent and an imide-based alkali metal salt. The negative electrode active material is predoped with alkali metal ions. The positive electrode binder has a Hansen solubility parameter-based RED value of more than 1 with respect to the electrolytic solution.
