Disclosed is a nonaqueous electrolyte for a lithium-ion secondary battery
that contains an addictive for preventing destruction of a solid
electrolyte interface (SEI) layer and hence decomposition of the
electrolyte that may cause generation of a gas, thereby preventing
swelling of the battery caused by the gas generated from the inside of
the battery at a high temperature. More specifically, the present
invention provides an electrolyte that includes, as an additive,
2-sulfobenzoic acid cyclic anhydride represented by the formula 1: The
electrolyte contains the additive in an amount of 0.1 to 10.0 wt. %.
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