| abstract |
The present invention provides a lithium secondary battery which has improved safety, mainly coming from use of an electrolyte solution which is not inflammable at room temperature (20°C), while not deteriorating output characteristics at low temperatures and room temperature or output maintenance characteristics after storage at high temperature (50°C). The lithium secondary battery of the present invention, encased in a container, is provided with a cathode and an anode, both capable of storing/releasing lithium ions, a separator which separates these electrodes from each other, and an electrolyte solution containing ethylene carbonate (EC), dimethyl carbonate (DMC) and ethyl methyl carbonate (EMC) as solvents, the DMC/EMC ratio by volume being 0.6 to 1.3. |