Nonaqueous electrolyte solution and lithium secondary battery using same

摘要

Disclosed is a nonaqueous electrolyte solution containing a sultone compound represented by the Formula 1 below (wherein R1 to R4 respectively represent a hydrogen, a fluorine, a hydrocarbon group with 1 to 12 carbon atoms that may contain fluorine atom(s), n represents an integer of 0 to 3, and when n is 2 or 3, the two or three R3 groups are independent from each other and the two or three R4 groups are independent from each other), and an ethylene carbonate having a hydrogen atom substituted by a fluorine atom. Also disclosed is a lithium secondary battery employing the nonaqueous electrolyte solution. This nonaqueous electrolyte solution does not cause an increase in the internal resistance of a nonaqueous electrochemical device and improves the lifespan characteristics of the device. The lithium secondary battery containing the nonaqueous electrolyte solution exhibits greatly improved cycle charge/discharge characteristics at high temperature, and has excellent charge/discharge load characteristics.;

主权项

1. A nonaqueous electrolyte solution comprising a nonaqueous solvent, an electrolyte, a sultone compound represented by the Formula 1 below at 0.1% by weight to 3% by weight, an ethylene carbonate having a hydrogen atom substituted by a fluorine atom at 0.1% by weight to 5% by weight, and a cyclic carbonate having a carbon-carbon unsaturated bond at 0.01 to 1 weight %, wherein, in Formula 1: R1 to R4 each independently represent a hydrogen atom, a fluorine atom, or a hydrocarbon group with 1 to 12 carbon atoms that may contain fluorine atom(s); n represents an integer of 0 to 3; and when n is 2 or 3, the two or three R3 groups are independent from each other and two or three R4 groups are independent from each other.