NONAQUEOUS ELECTROLYTIC SOLUTION AND NONAQUEOUS ELECTROLYTE SECONDARY BATTERY
A nonaqueous electrolytic solution that can provide a high energy density nonaqueous electrolyte secondary battery having a high capacity, excellent storage characteristics, and excellent cycle characteristics and suppressing the decomposition of an electrolytic solution and the deterioration thereof when used in a high-temperature environment includes an electrolyte, a nonaqueous solvent, and a compound represented by general formula (1): wherein R 1 , R 2 , and R 3 each independently represent a hydrogen atom, a cyano group, or an optionally halogen atom-substituted hydrogen group having 1 to 10 carbon atoms, with the priviso that R 1 and R 2 do not simultaneously represent hydrogen atoms.
1 . (canceled)
2 . A nonaqueous electrolyte secondary battery, comprising
a positive electrode having a positive-electrode active material capable of storing and releasing metal ions,
a negative electrode having a negative-electrode active material containing Si and capable of storing and releasing metal ions, and
a nonaqueous electrolytic solution comprising a compound containing 2 to 4 cyano groups and a carbonate containing a halogen atom.
3 . The nonaqueous electrolyte secondary battery according to claim 2 , wherein the compound containing 2 to 4 cyano groups is represented by formula (1):
NC—(X) n —CN (1),
where
each X is independently CH 2 , CFH, CF 2 , CHR, CFR, CR 2 , C═O, O, S, NH, or NR;
each R in CHR, CFR, CR 2 , and NR is independently an optionally substituted hydrocarbon group comprising from 1 to 5 carbon atoms or a cyano group; and
n is an integer of 1 or more.
4 . The nonaqueous electrolytic secondary battery according to claim 3 , wherein each X is independently CH 2 , CFH, CF 2 , CHR, CFR, CR 2 , O, S, or NR.
5 . The nonaqueous electrolytic secondary battery according to claim 3 , wherein the compound represented by the formula (1) is at least one compound selected from the group consisting of succinonitrile, glutaronitrile, adiponitrile, pimelonitrile, suberonitrile, azelanitrile, sebaconitrile, 3,3′-oxydipropionitrile, 3,3′-thiodipropionitrile, 1,2,3-propanetricarbonitrile, 1,3,5-pentanetricarbonitrile, undecanedinitrile, dodecanedinitrile, 1,2,3-tris(2-cyanoethoxy)propane, and tris(2-cyanoethyl)amine.
6 . The nonaqueous electrolytic secondary battery according to claim 3 , wherein n is an integer of 5 or more.
7 . The nonaqueous electrolytic secondary battery according to claim 3 , wherein the compound represented by the formula (1) is at least one compound selected from the group consisting of pimelonitrile, suberonitrile, azelanitrile, sebaconitrile, 3,3′-oxydipropionitrile, 1,3,5-pentanetricarbonitrile, undecanedinitrile, and dodecanedinitrile.
8 . The nonaqueous electrolytic secondary battery according to claim 2 , wherein the halogen atom-containing carbonate is at least one compound selected from the group consisting of fluoroethylene carbonate, 4,5-difluoroethylene carbonate, and a derivative thereof.
9 . The nonaqueous electrolytic secondary battery according to claim 2 , wherein the nonaqueous electrolytic solution contains 0.001 to 10% by weight of the compound containing 2 to 4 cyano groups.
10 . The nonaqueous electrolytic secondary battery according to claim 3 , wherein n is an integer of from 5 to 12.