NONAQUEOUS ELECTROLYTE SECONDARY BATTERY

摘要

PROBLEM TO BE SOLVED: To supply an increasing need for improvement of characteristics of a lithium nonaqueous electrolyte secondary battery in recent years, especially to overcome the problem that a large drop in capacity is caused by the reiteration of charge and discharge under a severe environment such as a high-temperature environment.SOLUTION: A nonaqueous electrolyte secondary battery comprises: a positive electrode and a negative electrode which are capable of occluding and releasing metal ions; a separator; and a nonaqueous electrolyte including a nonaqueous solvent and an electrolytic substance dissolved in the nonaqueous solvent. At least one of the positive electrode and the negative electrode is an electrode having an electrode mixture layer including an electrode active material and vinylidene fluoride-based polymer as a binding agent. As to the vinylidene fluoride-based polymer, the ratio (A/A) of an absorbance (A) in the vicinity of 1750 cmto an absorbance (A) in the vicinity of 3025 cmis 0.06-2 in IR spectrum measurement. The nonaqueous electrolyte contains a compound having an isocyanato group.