| 摘要 |
PROBLEM TO BE SOLVED: To provide a light-weight and safe secondary battery fit for use at high temperatures, by causing an electrolyte to contain a lithium imide salt and a fluorine-containing salt other than the lithium imide salt. SOLUTION: In a nonaqueous electrolyte secondary battery, a long cylindrical battery power generating element made up by winding a tape-like electrode plate 7 in a spiral manner is housed in an aluminum case, then the battery power generating element is impregnated with an electrolyte, and thereafter the case is airtightly sealed up. By adding a lithium imide salt, for example, LiN(SO2 CF2 CF3 )2 , to the electrolyte by a small amount of the order of 5 wt.% of the total weight of salts included in the electrolyte, a battery is obtained exhibiting excellent characteristics even after high temperature storage. This is because decomposing reaction of flourine-containing salts other than, and coexisting with, the lithium imide salt in the electrolyte is suppressed by the existence of the lithium imide salt in the electrolyte, and generation of hydrogen fluoride (HF) within the battery is suppressed. |
