| 摘要 |
PURPOSE:To improve long-term conservation stability by using a particular mixed liquid as a nonaqueous solvent. CONSTITUTION:A mixed liquid in which toluene of 15-25vol.% is mixed in propylene carbonate and ethylene carbonate whose volumetric ratios are from 75/25 to 35/65, respectively, is used as a nonaqueous solvent. It is thereby possible to prevent deterioration and deterioration of nonaqueous electrolyte and gas generation in a cell even during the use and storage of the cell so that a decrease in discharge capacity, an increase in the internal resistance of the cell and a drop of life performance of a charge and discharge cycle can be suppressed. Moreover, it is possible to stabilize a nonaqueous electrolyte even if the cell is used and stored at a comparatively high temperature and to increase a long term storage stability so that a nonaqueous electrolyte secondary cell of a high energy density can be obtained. |
