Nonaqueous electrolytic solution and nonaqueous electrolytic solution secondary battery

Patent metadata

Field	Value
Publication number	US-10991983-B2
Application number	US-201716305808-A
Country	US
Kind code	B2
Filing date	May 24, 2017
Priority date	May 30, 2016
Publication date	Apr 27, 2021
Grant date	Apr 27, 2021

Abstract

An object of the present invention is to provide a nonaqueous electrolytic solution and a nonaqueous electrolytic solution secondary battery capable of showing high output characteristics at a low temperature even after the battery is used to some extent, and capable of showing good high-rate properties, and further capable of showing sufficient performance again at low temperature even after stored at a high temperature. The nonaqueous electrolytic solution includes a nonaqueous solvent, an electrolyte dissolved in the nonaqueous solvent, (I) a difluoro ionic complex (1) represented by the general formula (1), and (II) at least one compound selected from the group consisting of a difluorophosphate salt, a monofluorophosphate salt, a specific salt having an imide anion, and a specific silane compound, and 95 mol % or more of the difluoro ionic complex (1) is a difluoro ionic complex (1-Cis) in a cis configuration represented by the general formula (1-Cis).

First claim

The invention claimed is:

1. A nonaqueous electrolytic solution for nonaqueous electrolytic solution secondary batteries, the nonaqueous electrolytic solution comprising:
a nonaqueous solvent,
an electrolyte dissolved in the nonaqueous solvent,
(I) a difluoro ionic complex (1) represented by the general formula (1), and
(II) at least one compound selected from the group consisting of a difluorophosphate salt, a monofluorophosphate salt, a salt having an imide anion represented by each of the general formulas (II-1) to (II-8) below, and a silane compound represented by the general formula (II-9) below,
wherein 95 mol % or more of the difluoro ionic complex (1) is a difluoro ionic complex (1-Cis) in a cis configuration represented by the general formula (1-Cis),

wherein in (1-Cis),

wherein in the general formula (1) and the general formula (1-Cis),
A + is any one selected from the group consisting of a metal ion, a proton, and an onium ion, and M is any one selected from the group consisting of Si, P, As, and Sb;
F is a fluorine atom; 0 is an oxygen atom;
t is 2 when M is Si, and t is 1 when M is P, As, or Sb;
X is an oxygen atom or —N(R 1 )—; N is a nitrogen atom; and R 1 is a hydrocarbon group having 1 to 10 carbon atoms and optionally having a hetero atom and/or a halogen atom (the hydrocarbon group optionally having a branched-chain or ring structure when the number of carbon atoms is 3 or more);
when X is —N(R 1 )—, and p is 0, X and W are bonded directly and optionally form a structure as shown in at least one selected from the general formulas (1-Cis-1) to (1-Cis-3) below; in the case of the general formula (1-Cis-2) below where the direct bond is a double bond, R 1 is not present,
Y is a carbon atom or a sulfur atom; q is 1 when Y is a carbon atom; q is 1 or 2 when Y is a sulfur atom;
W represents a hydrocarbon group having 1 to 10 carbon atoms and optionally having a hetero atom and/or a halogen atom (the hydrocarbon group optionally having a branched-chain or ring structure when the number of carbon atoms is 3 or more), or —N(R 2 )—; wherein,

R 2 represents a hydrogen atom, an alkaline metal, or a hydrocarbon group having 1 to 10 carbon atoms and optionally having a hetero atom and/or a halogen atom; when the number of carbon atoms is 3 or more, R 2 optionally has a branched-chain or ring structure;
p is 0 or 1, q is an integer of 0 to 2, r is an integer of 0 to 2, and further, p+r≥1,

wherein
in the general formulas (II-1) to (II-8), R 3 and R 14 are each independently a fluorine atom or an organic group selected from a straight chain or branched alkoxy group having 1 to 10 carbon atoms, an alkenyloxy group, an alkynyloxy group, a cycloalkoxy group having 3 to 10 carbon atoms, a cycloalkenyloxy group, and an aryloxy group having 6 to 10 carbon atoms, and at least one of a fluorine atom, an oxygen atom, and an unsaturated bond is optionally present in the organic group; Z 1 and Z 5 are each independently a fluorine atom or an organic group selected from a straight chain or branched alkyl group having 1 to 10 carbon atoms, an alkenyl group, an alkynyl group, a cycloalkyl group having 3 to 10 carbon atoms, a cycloalkenyl group, an aryl group having 6 to 10 carbon atoms, a straight chain or branched alkoxy group having 1 to 10 carbon atoms, an alkenyloxy group, an alkynyloxy group, a cycloalkoxy group having 3 to 10 carbon atoms, a cycloalkenyloxy group, and an aryloxy group having 6 to 10 carbon atoms, and at least one of a fluorine atom, an oxygen atom, and an unsaturated bond is optionally present in the organic group; n 1 represents an integer of 1 to 8; and B + , C + , and D + each independently represent any one selected from the group consisting of a metal ion, a proton, and an onium ion, and C + and D + are optionally identical; and
in the general formula (II-9), R 15 each independently represent a group having a carbon-carbon unsaturated bond; R 16 are each independently selected from a fluorine atom and a straight chain or branched alkyl group having 1 to 10 carbon atoms, and the alkyl group optionally has a fluorine atom and/or an oxygen atom; and a is 2 to 4.

2. The nonaqueous electrolytic solution according to claim 1 , wherein a combination of M, X, Y, W, p, q, r, and t in an anion moiety of the difluoro ionic complex (1) and in an anion moiety of the difluoro ionic complex (1-Cis) is at least one combination selected from (Cis-a), (Cis-b), (Cis-c), and (Cis-d):
(Cis-a) M=P; X=O; Y=C; p=q=t=1; and r=0;
(Cis-b) M=P; X=O; W=C(CF 3 ) 2 ; p=q=0; and r=t=1;
(Cis-c) M=Si; X=O; Y=C; p=q=1; t=2; and r=0; and
(Cis-d) M=P; X=N(R 1 ); Y=C; R 1 =CH 3 ; p=q=t=1; and r=0.

3. The nonaqueous electrolytic solution according to claim 1 , wherein the A + in the difluoro ionic complex (1-Cis) comprises at least one selected from the group consisting of a lithium ion, a sodium ion, a potassium ion, and a quaternary alkylammonium ion.

4. The nonaqueous electrolytic solution according to claim 1 , wherein
the content of the difluoro ionic complex (1-Cis) is in the range of 0.001 mass % or more and 20 mass % or less relative to the nonaqueous electrolytic solution,
the content of the compound shown in the (II) above is in the range of 0.01 mass % or more and 25 mass % or less relative to the nonaqueous electrolytic solution,
in the case where the compound shown in the (II) above comprises the difluorophosphate salt, the content of the difluorophosphate salt is in the range of 0.01 mass % or more and 3 mass % or less relative to the nonaqueous electrolytic solution,
in the case where the compound shown in the (II) above comprises the monofluorophosphate salt, the content of the monofluorophosphate salt is in the range of 0.01 mass % or more and 3 mass % or less relative to the nonaqueous electrolytic solution,
in the case where the compound shown in the (II) above comprises the salt having the imide anion represented by each of the general formulas (II-1) to (II-8) above, the content of the salt having the imide anion represented by each of the general formulas (II-1) to (II-8) above is in the range of 0.01 mass % or more and 10 mass % or less relative to the nonaqueous electrolytic solution,
in the case where the compound shown in the (II) above comprises the silane compound represented by the general formula (II-9) above, the content of the silane compound represented by the general formula (II-9) above is in the range of 0.001 mass % or more and 10 mass % or less relative to the nonaqueous electrolytic solution.

5. The nonaqueous electrolytic solution according to claim 1 , wherein a counter cation of the difluorophosphate salt and the monofluorophosphate salt is a lithium cation or a sodium cation.

6. The nonaqueous electrolytic solution according to claim 1 , wherein the difluoro ionic complex (1) further comprises (III) a difluoro ionic complex (1-Trans) in a trans configuration represented by the general formula (1-Trans),

wherein in (1-Trans)

wherein in the general formula (1-Trans),
A + is any one selected from the group consisting of a metal ion, a proton, and an onium ion, an

Assignees

• Central Glass Co Ltd

Inventors

• Itabashi Saori
• Suzuki Katsutoshi
• Takahashi Mikihiro
• Takeda Kazunari

Classifications

• H01M50/417

  Polyolefins · CPC title

• H01M50/429

  Natural polymers · CPC title

• H01M2300/002

  Inorganic electrolyte · CPC title

• H01M10/0563

  Liquid materials, e.g. for Li-SOCl2 cells · CPC title

• H01M50/411

  Organic material · CPC title