Patent ID: 11626618

Abstract:
An electrolyte solution for a lithium ion secondary battery, containing a compound (1) represented by the following formula (1): wherein R1 and R2 are each independently a C1-C4 alkyl group optionally containing an ether bond, and wherein chloride ion is present at a concentration of 1.0×10−6 to 1.0×103 ppm. Also disclosed is an electrolyte solution for a lithium ion secondary battery, containing an imidazolium cation (1-1) represented by the following formula (1-1), a bis(oxalato)borate anion, and a hexafluorophosphate anion, the formula (1-1) being:  wherein R1 and R2 are each independently a C1-C4 alkyl group optionally containing an ether bond, and wherein chloride ion is present at a concentration of 1.0×10−6 to 1.0×103 ppm.