LITHIUM ION CAPACITOR

摘要

Disclosed is a high-capacity lithium ion capacitor having high energy density and high power density. Specifically disclosed is a lithium ion capacitor comprising a positive electrode (1), a negative electrode (2) and an aprotic organic solvent solution of a lithium salt as electrolyte solution, wherein the positive electrode active material is a substance capable of reversibly carrying lithium ions and/or anions, the negative electrode active material is a substance capable of reversibly carrying lithium ions and anions, and the potentials of the positive and negative electrodes are not more than 2.0 V after short-circuiting the positive electrode and the negative electrode. An electrode unit (10) is formed by alternately stacking the positive electrodes (1) and the negative electrodes (2) via separators (3), and a cell is composed of two or more electrode units. A lithium metal (4) is arranged between two electrode units, and the negative and/or positive electrode is caused to carry lithium ions in advance through electrochemical contact between the lithium metal and the negative and/or positive electrode.