Electrolyte and secondary battery

摘要

An electrolyte includes a solvent and an electrolyte salt. The solvent contains at least one selected from ester compounds, lithium monofluorophosphate, and lithium difluorophosphate, and at least one selected from anhydrous compounds. The ester compounds are chain compounds having ester moieties, such as (—O—C(═O)—O—R), at both ends. The anhydrous compounds are cyclic compounds having, for example, a disulfonic anhydride group, (—S(O═)2—O—S(O═)2—).

主权项

1. A secondary battery comprising:
a positive electrode; a negative electrode; and an electrolyte including a solvent and an electrolyte salt, wherein the solvent contains A and B,
A is at least one selected from the group consisting of
ester compounds represented by formulae (1),ester compounds represented by formulae (2),ester compounds represented by formulae (3),lithium monofluorophosphate (Li2PFO3), andlithium difluorophosphate (LiPF2O2), andB is at least one selected from the group consisting of
anhydrous compounds represented by formulae (4), andanhydrous compounds represented by formulae (5):R11 and R13 each represent an alkyl group, an alkenyl group, an alkynyl group, an aryl group, a heterocyclic group, an alkyl, alkenyl, or alkynyl group substituted with an aromatic hydrocarbon group or an alicyclic hydrocarbon group, or a halogenated group thereof; R12 represents a linear or branched alkylene group, an arylene group, a divalent group containing an arylene group and an alkylene group, a C2-C12 divalent group containing an ether bond (—O—) and an alkylene group, or a halogenated group thereof;R14 and R16 each represent an alkyl group, an alkenyl group, an alkynyl group, an aryl group, a heterocyclic group, an alkyl, alkenyl, or alkynyl group substituted with an aromatic hydrocarbon group or an alicyclic hydrocarbon group, or a halogenated group thereof; R15 represents a linear or branched alkylene group, an arylene group, a divalent group containing an arylene group and an alkylene group, a C2-C12 divalent group containing an ether bond and an alkylene group, or a halogenated group thereof;R17 and R19 each represent an alkyl group, an alkenyl group, an alkynyl group, an aryl group, a heterocyclic group, an alkyl, alkenyl, or alkynyl group substituted with an aromatic hydrocarbon group or an alicyclic hydrocarbon group, or a halogenated group thereof; R18 represents a linear or branched alkylene group, an arylene group, a divalent group containing an arylene group and an alkylene group, a C2-C12 divalent group containing an ether bond and an alkylene group, or a halogenated group thereof;X21 represents a C2-C4 alkylene group that may be halogenated, a C2-C4 alkenylene group that may be halogenated, an arylene group that may be halogenated, or a derivative thereof; andX22 represents a C2-C4 alkylene group that may be halogenated, a C2-C4 alkenylene group that may be halogenated, an arylene group that may be halogenated, or a derivative thereof.