An electrical storage device of the present invention is characterized in that a positive
electrode, a negative
electrode, a
lithium electrode, and an
electrolyte capable of transferring
lithium ion is included, the
lithium electrode is arranged to be out of direct contact with the negative electrode, and lithium
ion can be supplied to the negative electrode by flowing a current between the
lithium electrode and the negative electrode through an
external circuit. With the above characteristic, problems such as non-uniform carrying of lithium
ion to the negative electrode, shape-change of a
cell, and temperature increase of an electrolytic solution under incomplete sealing of a
cell and the like can be easily solved. A using method of the electrical storage device is characterized in that, by using the
lithium electrode as a
reference electrode, the positive
electrode potential and negative
electrode potential can be measured, and the potential of the positive or negative electrode can be controlled when the electrical storage device is charged or discharged. Therefore, the potentials of the positive electrode and negative electrode can be monitored, thereby it can be easily determined whether deterioration of the electrical storage device is caused by the positive electrode or the negative electrode. Also, it is possible to control the device with the
potential difference between the negative electrode and
reference electrode, that is, the
negative potential. In addition, when characteristics deteriorate such as the
internal resistance increase, an appropriate amount of lithium ion can be supplied to the negative electrode and / or positive electrode by the
lithium electrode.