| abstract |
When an electrode material having a weight-average mesopore/macropore specific surface area within a specific range is used in a negative electrode mixture member (31), there arises an expansion of a cell caused by the generation of decomposed gas from a component of electrolyte solution during the pre-doping process of lithium ions. A potential drop upon the pre-doping process is adjusted so as to reduce or suppress the expansion of the cell. Specifically, since the pre-doping speed is increased, the negative electrode (30) can speedily reach the potential by which an SEI component made of lithium alkyl carbonate can be produced on the surface of the negative electrode (30). Consequently, the absolute amount of the gas produced by the decomposition of the electrolyte solution can be reduced, whereby the expansion of electric storage devices (A) and (B) can be reduced. |