JP2018203556A - Complex compound of lithium salt, and additive for lithium secondary battery - Google Patents

Abstract

To provide a novel complex compound of lithium salts, in which thermal stability and water stability are improved.SOLUTION: This invention relates to a complex compound of lithium salts, comprising: a lithium salt of phosphoric acid, boric acid, sulfonic acid, sulfuric acid, or sulfonylimide acid; a lithium salt of phosphoric acid having a fluorine atom bonded to P atom, boric acid having a fluorine atom bonded to B atom, or sulfonic acid having F atom bonded to S atom; and a compound selected from the following formulae (I) to (V).SELECTED DRAWING: None

Description

  The present disclosure relates to a lithium salt complex compound and an additive for a lithium secondary battery.

  Conventionally, lithium salt compounds have been usefully used in applications such as reaction reagents, synthesis reaction catalysts, electrolytes for various electrochemical devices, doping agents, and additives for lubricating oils. Since many of these lithium salt compounds have poor thermal stability and water stability, complex compounds having improved stability by treating the lithium salt compound with a complexable compound have been developed. Yes.

  Specific examples of lithium salt complex compounds include lithium hexafluoroarsenate, a complex compound of lithium hexafluorophosphate and acetonitrile (see Patent Document 1), lithium halide, lithium tetrafluoroborate, and the like. Complex compounds of lithium salts such as lithium hexafluorophosphate and compounds such as N, N, N ′, N ″, N ″ -pentamethyldiethylenetriamine (see Patent Document 2), lithium hexafluorophosphate and crown ether Complex compound (see Patent Document 3), lithium hexafluoroarsenate, complex compound of lithium hexafluorophosphate and 2-methyltetrahydrofuran (see Patent Document 4), complex compound of lithium hexafluorophosphate and pyridine (Patent Document) 5), lithium hexafluorophosphate and diethyl carbonate Complex compound of ethylene carbonate (see Patent Document 6), complex compounds and lithium hexafluorophosphate 1,4-dioxane (see Patent Document 7) it has been disclosed.

Japanese Patent Publication No.48-33733 Japanese Patent Publication No.53-31859 JP 59-151777 JP 6-16421 Special table 2002-514153 Japanese Patent No. 3555720 Japanese Patent No. 5862015

  An object of the present disclosure is to provide a novel lithium salt complex compound.

Means for solving the above problems include the following aspects.
<1> A halogen atom, an alkyl group that may be substituted with a halogen atom, an alkoxy group that may be substituted with a halogen atom, an alkenyl group that may be substituted with a halogen atom, or a substituent with a halogen atom When the substituent L is at least one substituent selected from the group consisting of a good alkynyl group, a cyclic ester group optionally substituted with at least one of a halogen atom and an alkyl group, an oxalato group, and an aryl group In addition,
Lithium phosphate salt A1 having the substituent L directly bonded to a phosphorus atom, lithium borate salt B1 having the substituent L directly bonded to a boron atom, sulfonic acid having the substituent L directly bonded to a sulfur atom One selected from the group consisting of a lithium salt C1, a lithium sulfate salt D1 having the substituent L directly bonded to a sulfur atom, and a sulfonylimidic acid lithium salt E1 having the substituent L directly bonded to a sulfur atom A first lithium salt;
Lithium phosphate A2 having a fluorine atom directly bonded to a phosphorus atom, lithium borate B2 having a fluorine atom directly bonded to a boron atom, and lithium sulfonate C2 having a fluorine atom directly bonded to a sulfur atom A second lithium salt which is one selected from the group;
Compound X, which is one selected from compounds represented by any one of the following formulas (I) to (V):
A lithium salt complex compound (except when the first lithium salt and the second lithium salt are the same compound).

[In the formula (I), R ¹ is a hydrogen atom, an alkyl group optionally substituted with a halogen atom, an alkenyl group optionally substituted with a halogen atom, an alkynyl group optionally substituted with a halogen atom, Or an aryl group,
R ² is selected from the group consisting of a halogen atom, an alkyl group optionally substituted with a halogen atom, an alkenyl group optionally substituted with a halogen atom, and an alkynyl group optionally substituted with a halogen atom. It represents an alkylene group having 2 to 9 carbon atoms which may be substituted with at least one substituent.
In formula (II), R ³ and R ⁴ are each independently a hydrogen atom, an alkyl group optionally substituted with a halogen atom, an alkenyl group optionally substituted with a halogen atom, or a halogen atom. An alkynyl group or an aryl group,
R ⁵ is selected from the group consisting of a halogen atom, an alkyl group optionally substituted with a halogen atom, an alkenyl group optionally substituted with a halogen atom, and an alkynyl group optionally substituted with a halogen atom. It represents an alkylene group having 2 to 9 carbon atoms which may be substituted with at least one substituent.
In the formula (III), R ⁶ is a halogen atom, an alkyl group which may be substituted with a halogen atom, an alkenyl group which may be substituted with a halogen atom, or an alkynyl group which may be substituted with a halogen atom. Represents an alkylene group having 2 to 9 carbon atoms which may be substituted with at least one substituent selected from the group consisting of
In the formula (IV), R ⁷ is a halogen atom, an alkyl group that may be substituted with a halogen atom, an alkenyl group that may be substituted with a halogen atom, or an alkynyl group that may be substituted with a halogen atom. Represents an alkylene group having 2 to 9 carbon atoms which may be substituted with at least one substituent selected from the group consisting of
In the formula (V), R ⁸ is a halogen atom, an alkyl group that may be substituted with a halogen atom, an alkenyl group that may be substituted with a halogen atom, or an alkynyl group that may be substituted with a halogen atom. Represents an alkylene group having 2 to 9 carbon atoms which may be substituted with at least one substituent selected from the group consisting of ]

<2> The first lithium salt is lithium difluorophosphate, lithium hexafluorophosphate, lithium tetrafluoroborate, lithium bis (oxalato) borate, lithium trifluoromethanesulfonate, lithium methylsulfate, lithium benzenesulfonate, It is one selected from the group consisting of lithium fluorosulfonate, lithium bis (trifluoromethanesulfonyl) imide, lithium bis (fluorosulfonyl) imide, and lithium bis (perfluoroethylsulfonyl) imide,
The second lithium salt is one selected from the group consisting of lithium difluorophosphate, lithium hexafluorophosphate, lithium tetrafluoroborate, and lithium fluorosulfonate,
Compound X is N-methylpyrrolidone, N-vinylpyrrolidone, 1,3-dimethyl-2-imidazolidinone, 1,3-dioxolan-2-one, 4-methyl-1,3-dioxolan-2-one From the group consisting of 4-fluoro-1,3-dioxolan-2-one, 1,3-dioxolane, 1,3-dioxane, and 2-fluoro-1,3,2-dioxaphosphorinane-2-oxide The lithium salt complex compound according to <1>, which is one selected.

<3> The first lithium salt is lithium difluorophosphate, lithium hexafluorophosphate, lithium tetrafluoroborate, lithium bis (oxalato) borate, lithium trifluoromethanesulfonate, lithium fluorosulfonate, and lithium methylsulfate One selected from the group consisting of
The second lithium salt is one selected from the group consisting of lithium difluorophosphate, lithium hexafluorophosphate, lithium tetrafluoroborate, and lithium fluorosulfonate,
Compound X is one selected from the group consisting of N-methylpyrrolidone, 1,3-dioxolan-2-one, 4-fluoro-1,3-dioxolan-2-one, and 1,3-dioxolane The lithium salt complex compound according to <1> or <2>.

<4> a complex compound comprising lithium hexafluorophosphate, lithium difluorophosphate and N-methylpyrrolidone;
A complex compound comprising lithium hexafluorophosphate, lithium difluorophosphate and 1,3-dioxolan-2-one,
A complex compound comprising lithium hexafluorophosphate, lithium difluorophosphate and 4-fluoro-1,3-dioxolan-2-one,
A complex compound comprising lithium bis (oxalato) borate, lithium difluorophosphate and 1,3-dioxolan-2-one,
A complex compound comprising lithium bis (oxalato) borate, lithium difluorophosphate and 4-fluoro-1,3-dioxolan-2-one,
A complex compound comprising lithium methyl sulfate, lithium hexafluorophosphate and 1,3-dioxolan-2-one,
A complex compound comprising lithium methyl sulfate, lithium hexafluorophosphate and 4-fluoro-1,3-dioxolan-2-one,
A complex compound comprising lithium methyl sulfate, lithium hexafluorophosphate and 1,3-dioxolane,
A complex compound comprising lithium methyl sulfate, lithium difluorophosphate and 1,3-dioxolan-2-one,
A complex compound comprising lithium methyl sulfate, lithium difluorophosphate and 4-fluoro-1,3-dioxolan-2-one,
A complex compound comprising lithium methyl sulfate, lithium difluorophosphate and 1,3-dioxolane;
A complex compound comprising lithium trifluoromethanesulfonate, lithium hexafluorophosphate and 1,3-dioxolan-2-one,
A complex compound comprising lithium trifluoromethanesulfonate, lithium hexafluorophosphate and 4-fluoro-1,3-dioxolan-2-one;
A complex compound comprising lithium trifluoromethanesulfonate, lithium difluorophosphate and 1,3-dioxolan-2-one,
A complex compound comprising lithium trifluoromethanesulfonate, lithium difluorophosphate and 4-fluoro-1,3-dioxolan-2-one,
A complex compound comprising lithium fluorosulfonate, lithium hexafluorophosphate and 1,3-dioxolan-2-one,
A complex compound comprising lithium fluorosulfonate, lithium hexafluorophosphate and 4-fluoro-1,3-dioxolan-2-one,
A complex compound comprising lithium fluorosulfonate, lithium hexafluorophosphate and 1,3-dioxolane,
A complex compound comprising lithium fluorosulfonate, lithium difluorophosphate and 1,3-dioxolan-2-one,
A complex compound comprising lithium fluorosulfonate, lithium difluorophosphate and 4-fluoro-1,3-dioxolan-2-one,
A complex compound comprising lithium fluorosulfonate, lithium difluorophosphate and 1,3-dioxolane,
A complex compound comprising lithium fluorosulfonate, lithium tetrafluoroborate and 1,3-dioxolan-2-one,
A complex compound consisting of lithium fluorosulfonate, lithium tetrafluoroborate and 4-fluoro-1,3-dioxolan-2-one, or
The lithium salt complex compound according to any one of <1> to <3>, which is a complex compound composed of lithium fluorosulfonate, lithium tetrafluoroborate, and 1,3-dioxolane.

<5> An additive for a lithium secondary battery, comprising the lithium salt complex compound according to any one of <1> to <4>.

  According to the present disclosure, a novel lithium salt complex compound is provided.

In this specification, a numerical range expressed using “to” means a range including numerical values described before and after “to” as a lower limit value and an upper limit value.
In this specification, the amount of each component in the composition is the total amount of the plurality of substances present in the composition unless there is a specific indication when there are a plurality of substances corresponding to each component in the composition. Means.

[Lithium salt complex compound]
The lithium salt complex compound of the present disclosure is:
A halogen atom, an alkyl group optionally substituted with a halogen atom, an alkoxy group optionally substituted with a halogen atom, an alkenyl group optionally substituted with a halogen atom, an alkynyl group optionally substituted with a halogen atom In the case where at least one substituent selected from the group consisting of a cyclic ester group, an oxalato group, and an aryl group, which may be substituted with at least one of a halogen atom and an alkyl group, is the substituent L,
Lithium phosphate A1 having a substituent L directly bonded to a phosphorus atom, Lithium borate B1 having a substituent L directly bonded to a boron atom, Lithium sulfonate C1 having a substituent L directly bonded to a sulfur atom 1st lithium salt which is 1 type selected from the group which consists of lithium sulfate salt D1 which has the substituent L couple | bonded directly with a sulfur atom, and sulfonyl imido acid lithium salt E1 which has the substituent L couple | bonded directly with a sulfur atom When,
Lithium phosphate A2 having a fluorine atom directly bonded to a phosphorus atom, lithium borate B2 having a fluorine atom directly bonded to a boron atom, and lithium sulfonate C2 having a fluorine atom directly bonded to a sulfur atom A second lithium salt which is one selected from the group;
Compound X, which is one selected from compounds represented by any one of the following formulas (I) to (V):
A new lithium salt complex compound (except when the first lithium salt and the second lithium salt are the same compound).
The meanings of symbols in formulas (I) to (V) will be described later.

In the lithium salt complex compound of the present disclosure, the second lithium salt is included in the range of the first lithium salt. More specifically, the lithium phosphate salt A2 is included in the range of the lithium phosphate salt A1, the lithium borate salt B2 is included in the range of the lithium borate salt B1, and the lithium sulfonate salt C2 is the lithium sulfonate salt C1. Included in the range.
However, as described above, a lithium salt complex compound in which the first lithium salt and the second lithium salt are the same compound (for example, lithium difluorophosphate as the first lithium salt and difluorophosphoric acid as the second lithium salt) Lithium salt complex compounds, etc., which are combinations of lithium and compound X, etc. are excluded from the scope of the lithium salt complex compounds of the present disclosure.

The lithium salt complex compound of the present disclosure has an endotherm at a temperature at which each of the raw material compounds for forming the lithium salt complex compound (that is, the first lithium salt, the second lithium salt, and the compound X) is not recognized alone. Thermal dissociation behavior is observed. In this respect, the lithium salt complex compound of the present disclosure is distinguished from a simple mixture of the first lithium salt, the second lithium salt, and the compound X.
Moreover, the lithium salt complex compound of this indication is a compound excellent in thermal stability by said point.

  Next, the first lithium salt, the second lithium salt, and the compound X in the lithium salt complex compound of the present disclosure will be described.

<First lithium salt>
The first lithium salt includes a lithium phosphate salt A1 having a substituent L directly bonded to a phosphorus atom, a lithium borate salt B1 having a substituent L directly bonded to a boron atom, and a substituent L directly bonded to a sulfur atom. One selected from the group consisting of lithium sulfonic acid salt C1 having lithium, lithium sulfate salt D1 having substituent L directly bonded to a sulfur atom, and lithium sulfonylimide acid E1 having substituent L directly bonded to a sulfur atom It is.

The substituent L is a halogen atom, an alkyl group that may be substituted with a halogen atom, an alkoxy group that may be substituted with a halogen atom, an alkenyl group that may be substituted with a halogen atom, or a halogen atom. It is at least one selected from the group consisting of an optionally substituted alkynyl group, a halogen atom and an alkyl group, an optionally substituted cyclic ester group, an oxalate group, and an aryl group.
The substituent L may be one type or two or more types. When two or more substituents L are present, they may be the same or different.

Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
As the halogen atom, a fluorine atom is preferable.

The alkyl group which may be substituted with a halogen atom means an unsubstituted alkyl group or a halogenated alkyl group.
The halogenated alkyl group means an alkyl group substituted with at least one halogen atom.
The unsubstituted alkyl group and the halogenated alkyl group may be linear, branched or cyclic, respectively.
Examples of the unsubstituted alkyl group include an unsubstituted alkyl group having 1 to 12 carbon atoms, specifically, methyl group, ethyl group, n-propyl group, isopropyl group, 1-ethylpropyl group, n -Butyl group, isobutyl group, sec-butyl group, tert-butyl group, 2-methylbutyl group, 3,3-dimethylbutyl group, n-pentyl group, isopentyl group, neopentyl group, 1-methylpentyl group, n-hexyl Group, isohexyl group, sec-hexyl group, tert-hexyl group, n-heptyl group, isoheptyl group, sec-heptyl group, tert-heptyl group, n-octyl group, isooctyl group, sec-octyl group, tert-octyl group , Nonyl group, decyl group, undecyl group, dodecyl group and the like.
The unsubstituted alkyl group is preferably a methyl group, an ethyl group, an n-propyl group, or an isopropyl group, and more preferably a methyl group or an ethyl group.
Examples of the halogenated alkyl group include, for example, a halogenated alkyl group having 1 to 6 carbon atoms, specifically, a fluoromethyl group, a difluoromethyl group, a trifluoromethyl group, and a 2,2,2-trifluoroethyl group. Perfluoroethyl group, perfluoropropyl group, perfluorobutyl group, perfluoropentyl group, perfluorohexyl group, perfluoroisopropyl group, perfluoroisobutyl group, chloromethyl group, chloroethyl group, chloropropyl group, bromomethyl group, Examples thereof include a bromoethyl group, a bromopropyl group, a methyl iodide group, an ethyl iodide group, and a propyl iodide group.
As the halogenated alkyl group, a fluoroalkyl group having 1 to 6 carbon atoms is preferable, and a fluoromethyl group, a difluoromethyl group, a trifluoromethyl group, a 2,2,2-trifluoroethyl group, a perfluoroethyl group, a perfluoro group. A propyl group, a perfluorobutyl group, or a perfluorohexyl group is more preferable.

The alkoxy group which may be substituted with a halogen atom means an unsubstituted alkoxy group or a halogenated alkoxy group.
The halogenated alkoxy group means an alkoxy group substituted with at least one halogen atom.
The unsubstituted alkoxy group and the halogenated alkoxy group may be linear, branched or cyclic, respectively.
Examples of the unsubstituted alkoxy group include an unsubstituted alkoxy group having 1 to 6 carbon atoms, specifically, a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, an isobutoxy group, sec- Examples include butoxy, tert-butoxy, pentyloxy, 2-methylbutoxy, 1-methylpentyloxy, neopentyloxy, 1-ethylpropoxy, hexyloxy, 3,3-dimethylbutoxy It is done.
As an unsubstituted alkoxy group, an ethoxy group or a methoxy group is preferable, and a methoxy group is more preferable.
Examples of the halogenated alkoxy group include groups having a structure in which the above-mentioned unsubstituted C1-C6 alkoxy group is substituted with at least one halogen atom.

The alkenyl group which may be substituted with a halogen atom means an unsubstituted alkenyl group or a halogenated alkenyl group.
A halogenated alkenyl group means an alkenyl group substituted with at least one halogen atom.
The unsubstituted alkenyl group and halogenated alkenyl group may each be linear, branched or cyclic.
Examples of the unsubstituted alkenyl group include an unsubstituted alkenyl group having 2 to 6 carbon atoms, specifically, vinyl group, 1-propenyl group, allyl group (2-propenyl group), isopropenyl group, 1-butenyl group, 2-butenyl group, 3-butenyl group, pentenyl group, hexenyl group, 2-methyl-2-propenyl group, 1-methyl-2-propenyl group, 2-methyl-1-propenyl group, hexenyl group Etc.
As an unsubstituted alkenyl group, a vinyl group or an allyl group is preferable, and a vinyl group is more preferable.
Examples of the halogenated alkenyl group include groups having a structure in which an unsubstituted alkenyl group having 2 to 6 carbon atoms is substituted with at least one halogen atom.

The alkynyl group which may be substituted with a halogen atom means an unsubstituted alkynyl group or a halogenated alkynyl group.
A halogenated alkynyl group means an alkynyl group substituted by at least one halogen atom.
The unsubstituted alkynyl group and halogenated alkynyl group may each be linear, branched or cyclic.
Examples of the unsubstituted alkynyl group include an unsubstituted alkynyl group having 2 to 6 carbon atoms, specifically, an ethynyl group, a 1-propynyl group, a 2-propynyl group (synonymous with a propargyl group), 1- Butynyl, 2-butynyl, 3-butynyl, 1-pentynyl, 2-pentynyl, 3-pentynyl, 4-pentynyl, 5-hexynyl, 1-methyl-2-propynyl, 2-methyl -3-butynyl group, 2-methyl-3-pentynyl group, 1-methyl-2-butynyl group, 1,1-dimethyl-2-propynyl, 1,1-dimethyl-2-butynyl group, 1-hexynyl group, etc. Is mentioned.
Examples of the halogenated alkynyl group include groups having a structure in which the aforementioned unsubstituted C2-C6 alkynyl group is substituted with at least one halogen atom.

The cyclic ester group which may be substituted with at least one of a halogen atom and an alkyl group is selected from the group consisting of an unsubstituted cyclic ester group or an unsubstituted cyclic ester group consisting of a halogen atom and an alkyl group. It means a group having a structure substituted by at least one substituent.
Examples of the unsubstituted cyclic ester group include a group in which one hydrogen atom is dissociated from a lactone. Examples of the lactone include α-acetolactone, β-propiolactone, γ-butyrolactone, and δ-valerolactone.
The halogen atom as a substituent for the cyclic ester group has the same meaning as the halogen atom as the substituent L described above.
Examples of the alkyl group as a substituent for the cyclic ester group include the same as the unsubstituted alkyl group having 1 to 6 carbon atoms as the substituent L described above.

  The oxalato group is a group represented by the following formula (a). * Represents a bonding position.

The concept of the aryl group in the substituent L includes both an unsubstituted aryl group and a substituted aryl group.
Examples of the aryl group in the substituent L include an unsubstituted aryl group having 6 to 20 carbon atoms and a substituted aryl group having 7 to 20 carbon atoms. Specifically, a phenyl group; a hydrogen atom from an alkylbenzene Is a group in which one hydrogen atom is removed (eg, benzyl group, tolyl group, xylyl group, methicyl group, etc.); naphthyl group;
The substituent in the substituted aryl group is not particularly limited. For example, the above-described halogen atom, halogenated alkyl group, unsubstituted alkoxy group, halogenated alkoxy group, unsubstituted alkenyl group, halogenated alkenyl group, Examples thereof include a substituted alkynyl group and a halogenated alkynyl group.
As the aryl group, a phenyl group is preferable.

(Lithium phosphate A1)
The lithium phosphate salt A1 has a substituent L that is directly bonded to a phosphorus atom.
In the lithium phosphate salt A1, the substituent L directly bonded to the phosphorus atom includes fluorine atom, methoxy group, ethoxy group, isopropoxy group, 2,2,2-trifluoroethoxy group, pentafluoroethoxy group, phenoxy group Or an oxalato group is preferred.

Examples of the lithium phosphate salt A1 include lithium hexafluorophosphate, lithium difluorophosphate, dimethyl lithium phosphate, diethyl lithium phosphate, diisopropyl lithium phosphate, and bis (2,2,2-trifluoroethyl phosphate). Examples thereof include lithium, bis (pentafluoroethyl) lithium phosphate, diphenyl lithium phosphate, lithium tetrafluorooxalatophosphate, lithium difluorobis (oxalato) phosphate, and lithium tris (oxalato) phosphate.
As the lithium phosphate salt A1, lithium difluorophosphate or lithium hexafluorophosphate is preferable.

(Lithium borate B1)
The lithium borate salt B1 has a substituent L directly bonded to a boron atom.
In the lithium borate salt B1, the substituent L directly bonded to the boron atom is preferably a fluorine atom or an oxalato group.

Examples of the lithium borate salt B1 include lithium tetrafluoroborate, lithium difluorooxalatoborate, lithium bis (oxalato) borate, and the like.
As the lithium borate salt B1, lithium tetrafluoroborate or lithium bis (oxalato) borate is preferable, and lithium bis (oxalato) borate is more preferable.

(Sulphonic acid lithium salt C1)
The sulfonic acid lithium salt C1 has a substituent L directly bonded to a sulfur atom.
In the sulfonic acid lithium salt C1, the substituent L directly bonded to the sulfur atom is preferably a fluorine atom, a methyl group, a trifluoromethyl group, a vinyl group, an allyl group, or a phenyl group.

Examples of the lithium sulfonate C1 include lithium fluorosulfonate, lithium methanesulfonate, lithium trifluoromethanesulfonate, lithium vinylsulfonate, lithium allylsulfonate, and lithium benzenesulfonate.
As the lithium sulfonate C1, lithium fluorosulfonate, lithium trifluoromethanesulfonate, or lithium benzenesulfonate is preferable.

(Lithium sulfate D1)
The lithium sulfate salt D1 has a substituent L that is directly bonded to a sulfur atom.
In the lithium sulfate salt D1, the substituent L directly bonded to the sulfur atom is preferably an alkyl group having 1 to 20 carbon atoms, more preferably an alkyl group having 1 to 12 carbon atoms, and still more preferably a methyl group or a dodecyl group.

Examples of the lithium sulfate salt D1 include methyl lithium sulfate and lithium dodecyl sulfate.
As the lithium sulfate salt D1, lithium methyl sulfate is preferable.

(Lithium sulfonylimide acid salt E1)
The sulfonylimido lithium salt E1 has a substituent L that is directly bonded to a sulfur atom.
In the sulfonylimido lithium salt E1, the substituent L directly bonded to the sulfur atom is preferably a fluorine atom, a trifluoromethyl group, or a pentafluoroethyl group.

  Examples of the sulfonylimido lithium salt E1 include lithium bis (trifluoromethanesulfonyl) imide, lithium bis (fluorosulfonyl) imide, lithium bis (perfluoroethylsulfonyl) imide, and the like.

<Second lithium salt>
The second lithium salt includes lithium phosphate A2 having a fluorine atom directly bonded to a phosphorus atom, lithium borate B2 having a fluorine atom directly bonded to a boron atom, and a sulfone having a fluorine atom directly bonded to a sulfur atom. It is one selected from the group consisting of lithium acid salt C2.
As described above, the lithium phosphate salt A2 is included in the range of the lithium phosphate salt A1, the lithium borate salt B2 is included in the range of the lithium borate salt B1, and the lithium sulfonate C2 is the lithium sulfonate salt C1. Included in the range.
However, as described above, a combination in which the first lithium salt and the second lithium salt are the same compound is excluded from the scope of the lithium salt complex compound of the present disclosure.

(Lithium phosphate A2)
The lithium phosphate salt A2 in the second lithium salt is a lithium phosphate salt having a fluorine atom directly bonded to a phosphorus atom in the lithium phosphate salt A1 in the first lithium salt.
Examples of the lithium phosphate salt A2 include lithium hexafluorophosphate, lithium difluorophosphate, lithium tetrafluorooxalatrate, and lithium difluorobis (oxalato) phosphate.
As the lithium phosphate salt A2, lithium difluorophosphate or lithium hexafluorophosphate is preferable.

(Lithium borate B2)
The lithium borate salt B2 in the second lithium salt is a lithium borate salt having a fluorine atom directly bonded to a boron atom in the lithium borate salt B1 in the first lithium salt.
Examples of the lithium borate salt B2 include lithium tetrafluoroborate and lithium difluorooxalatoborate.
As the fluorine-containing lithium borate salt B2, lithium tetrafluoroborate is preferable.

(Sulfuric acid lithium salt C2)
The sulfonic acid lithium salt C2 in the second lithium salt is a sulfonic acid lithium salt having a fluorine atom directly bonded to a sulfur atom in the sulfonic acid lithium salt C1 in the first lithium salt.
Examples of the lithium sulfonate C2 include lithium fluorosulfonate.

<Compound X>
Compound X is one selected from compounds represented by any of the following formulas (I) to (V).

(Compound represented by formula (I))

In formula (I), R ¹ represents a hydrogen atom, an alkyl group which may be substituted with a halogen atom, an alkenyl group which may be substituted with a halogen atom, an alkynyl group which may be substituted with a halogen atom, or Represents an aryl group,
R ² is selected from the group consisting of a halogen atom, an alkyl group optionally substituted with a halogen atom, an alkenyl group optionally substituted with a halogen atom, and an alkynyl group optionally substituted with a halogen atom. It represents an alkylene group having 2 to 9 carbon atoms which may be substituted with at least one substituent.

The alkyl group that may be substituted with a halogen atom in R ¹ has the same meaning as the alkyl group that may be substituted with the halogen atom exemplified in the section of the substituent L.
The alkyl group which may be substituted with a halogen atom in R ¹ is preferably an unsubstituted alkyl group having 1 to 12 carbon atoms or a halogenated alkyl group having 1 to 6 carbon atoms, more preferably a methyl group or an ethyl group. Preferably, a methyl group is more preferable.

The alkenyl group optionally substituted with a halogen atom in R ¹ has the same meaning as the alkenyl group optionally substituted with the halogen atom exemplified in the section of the substituent L.
The alkenyl group optionally substituted with a halogen atom in R ¹ is preferably an unsubstituted alkenyl group having 2 to 6 carbon atoms or a halogenated alkenyl group having 2 to 6 carbon atoms, and an unsubstituted alkenyl group having 2 to 2 carbon atoms. 6 alkenyl groups are more preferred, vinyl groups, 1-propenyl groups, allyl groups, or isopropenyl groups are more preferred, and vinyl groups are even more preferred.

The alkynyl group optionally substituted with a halogen atom in R ¹ has the same meaning as the alkynyl group optionally substituted with the halogen atom exemplified in the section of the substituent L.
The alkynyl group which may be substituted with a halogen atom in R ¹ is preferably an unsubstituted alkynyl group having 2 to 6 carbon atoms or a halogenated alkynyl group having 2 to 6 carbon atoms.

The aryl group in R ¹ has the same meaning as the aryl group in the substituent L.
The aryl group for R ¹ is preferably an unsubstituted aryl group having 6 to 10 carbon atoms, and more preferably a phenyl group.

In formula (I), R ² is a halogen atom, an alkyl group which may be substituted with a halogen atom, an alkenyl group which may be substituted with a halogen atom, or an alkynyl group which may be substituted with a halogen atom. Represents an alkylene group having 2 to 9 carbon atoms which may be substituted with at least one substituent selected from the group consisting of
Here, the alkylene group having 2 to 9 carbon atoms which may be substituted by the above substituent is an unsubstituted alkylene group having 2 to 9 carbon atoms or an unsubstituted alkylene group having 2 to 9 carbon atoms. It means a group having a structure substituted by the above substituent.

The alkylene group represented by R ² may be linear, branched or cyclic.
Examples of the alkylene group represented by R ² include an ethylene group, a propylene group, a butylene group, a pentylene group, a hexylene group, a heptylene group, and an octylene group.
The alkylene group represented by R ² is preferably an alkylene group having 2 to 6 carbon atoms, and more preferably an alkylene group having 2 to 4 carbon atoms.
As the alkylene group represented by R ² , a propylene group is particularly preferable.

Examples of the substituent that can be substituted with respect to the alkylene group in R ² include a halogen atom, an unsubstituted alkyl group, a halogenated alkyl group, an unsubstituted alkenyl group, and a halogenated alkenyl group in the description of the substituent L. , Unsubstituted alkynyl groups, and those exemplified as halogenated alkynyl groups.

Examples of the compound represented by the formula (I) include N-methylpyrrolidone and N-vinylpyrrolidone.
As the compound represented by the formula (I), N-methylpyrrolidone or N-vinylpyrrolidone is preferable, and N-methylpyrrolidone is more preferable.

(Compound represented by formula (II))

In formula (II), R ³ and R ⁴ are each independently a hydrogen atom, an alkyl group optionally substituted with a halogen atom, an alkenyl group optionally substituted with a halogen atom, or a halogen atom. An alkynyl group or an aryl group,
R ⁵ is selected from the group consisting of a halogen atom, an alkyl group optionally substituted with a halogen atom, an alkenyl group optionally substituted with a halogen atom, and an alkynyl group optionally substituted with a halogen atom. It represents an alkylene group having 2 to 9 carbon atoms which may be substituted with at least one substituent.

R ³ and R ⁴ in the formula (II) each have the same meaning as R ¹ in the formula (I), and the preferred embodiments are also the same.
R ⁵ in formula (II) has the same meaning as R ² in formula (I), and the preferred embodiments are also the same.
However, as R ⁵ in formula (II), an ethylene group is particularly preferable.

Examples of the compound represented by the formula (II) include 1-methyl-2-imidazolidinone, 1,3-dimethyl-2-imidazolidinone, and the like.
As the compound represented by the formula (II), 1,3-dimethyl-2-imidazolidinone is preferable.

(Compound represented by formula (III))

In the formula (III), R ⁶ is a halogen atom, an alkyl group which may be substituted with a halogen atom, an alkenyl group which may be substituted with a halogen atom, or an alkynyl group which may be substituted with a halogen atom. Represents an alkylene group having 2 to 9 carbon atoms which may be substituted with at least one substituent selected from the group consisting of

R ⁶ in formula (III) has the same meaning as R ² in formula (I), and the preferred embodiments are also the same.
However, as R ⁶ in formula (III), an ethylene group is particularly preferable.

Examples of the compound represented by the formula (III) include 1,3-dioxolan-2-one, 4-methyl-1,3-dioxolan-2-one, 4-ethyl-1,3-dioxolane-2- ON, 4,4-dimethyl-1,3-dioxolan-2-one, 4,5-dimethyl-1,3-dioxolan-2-one, 4-vinyl-1,3-dioxolan-2-one, 4- Examples include ethynyl-1,3-dioxolan-2-one, 4-fluoro-1,3-dioxolan-2-one, 4,5-difluoro-1,3-dioxolan-2-one, and the like.
Examples of the compound represented by the formula (III) include 1,3-dioxolan-2-one, 4-methyl-1,3-dioxolan-2-one, and 4-fluoro-1,3-dioxolan-2-one Are preferred, and 1,3-dioxolan-2-one is more preferred.

(Compound represented by formula (IV))

In the formula (IV), R ⁷ is a halogen atom, an alkyl group that may be substituted with a halogen atom, an alkenyl group that may be substituted with a halogen atom, or an alkynyl group that may be substituted with a halogen atom. Represents an alkylene group having 2 to 9 carbon atoms which may be substituted with at least one substituent selected from the group consisting of

R ⁷ in formula (IV) has the same meaning as R ² in formula (I), and the preferred embodiments are also the same.
However, R ⁷ in formula (IV) is particularly preferably an ethylene group.

Examples of the compound represented by the formula (IV) include 1,3-dioxolane, 4-methyl-1,3-dioxolane, 1,3-dioxane, 4-methyl-1,3-dioxane, 4-phenyl- Examples include 1,3-dioxane and 1,3-dioxepane.
As the compound represented by the formula (IV), 1,3-dioxolane or 1,3-dioxane is preferable, and 1,3-dioxolane is more preferable.

(Compound represented by Formula (V))

In the formula (V), R ⁸ is a halogen atom, an alkyl group that may be substituted with a halogen atom, an alkenyl group that may be substituted with a halogen atom, or an alkynyl group that may be substituted with a halogen atom. Represents an alkylene group having 2 to 9 carbon atoms which may be substituted with at least one substituent selected from the group consisting of

R ⁸ in formula (V) has the same meaning as R ² in formula (I), and the preferred embodiments are also the same.

Examples of the compound represented by the formula (V) include 2-fluoro-1,3,2-dioxaphosphorane-2-oxide, 2-fluoro-1,3,2-dioxaphosphorinane-2- And oxides.
As the compound represented by the formula (V), 2-fluoro-1,3,2-dioxaphosphorinane-2-oxide is preferable.

[Preferred embodiment of lithium salt complex compound]
A preferred embodiment of the lithium salt complex compound of the present disclosure is:
The first lithium salt is lithium difluorophosphate, lithium hexafluorophosphate, lithium tetrafluoroborate, lithium bis (oxalato) borate, lithium trifluoromethanesulfonate, lithium methylsulfate, lithium benzenesulfonate, lithium fluorosulfonate , Lithium bis (trifluoromethanesulfonyl) imide, lithium bis (fluorosulfonyl) imide, and lithium bis (perfluoroethylsulfonyl) imide,
The second lithium salt is one selected from the group consisting of lithium difluorophosphate, lithium hexafluorophosphate, lithium tetrafluoroborate, and lithium fluorosulfonate;
Compound X is N-methylpyrrolidone, N-vinylpyrrolidone, 1,3-dimethyl-2-imidazolidinone, 1,3-dioxolan-2-one, 4-methyl-1,3-dioxolan-2-one, Selected from the group consisting of 4-fluoro-1,3-dioxolan-2-one, 1,3-dioxolane, 1,3-dioxane, and 2-fluoro-1,3,2-dioxaphosphorinane-2-oxide It is the aspect which is 1 type.

A more preferred embodiment of the lithium salt complex compound of the present disclosure is:
The first lithium salt is selected from the group consisting of lithium difluorophosphate, lithium hexafluorophosphate, lithium tetrafluoroborate, lithium bis (oxalato) borate, lithium trifluoromethanesulfonate, lithium fluorosulfonate, and lithium methylsulfate. One kind to be selected,
The second lithium salt is one selected from the group consisting of lithium difluorophosphate, lithium hexafluorophosphate, lithium tetrafluoroborate, and lithium fluorosulfonate;
Compound X is one selected from the group consisting of N-methylpyrrolidone, 1,3-dioxolan-2-one, 4-fluoro-1,3-dioxolan-2-one, and 1,3-dioxolane It is an aspect.

  Hereinafter, although the exemplary compound (complex compound 1-complex compound 36) of the lithium salt complex compound of this indication is shown, the lithium salt complex compound of this indication is not limited to the following example compounds.

・ Complex compound 1
A complex compound comprising lithium hexafluorophosphate, lithium difluorophosphate and N-methylpyrrolidone.
・ Complex compound 2
A complex compound comprising lithium hexafluorophosphate, lithium difluorophosphate and 1,3-dioxolan-2-one.
・ Complex compound 3
A complex compound comprising lithium hexafluorophosphate, lithium difluorophosphate, and 4-fluoro-1,3-dioxolan-2-one.
・ Complex compound 4
A complex compound comprising lithium hexafluorophosphate, lithium difluorophosphate, and 1,3-dioxolane.
・ Complex compound 5
A complex compound comprising lithium bis (oxalato) borate, lithium difluorophosphate, and N-methylpyrrolidone.
・ Complex compound 6
A complex compound comprising lithium bis (oxalato) borate, lithium difluorophosphate, and 1,3-dioxolan-2-one.
・ Complex compound 7
A complex compound comprising lithium bis (oxalato) borate, lithium difluorophosphate and 4-fluoro-1,3-dioxolan-2-one.
・ Complex compound 8
A complex compound comprising lithium bis (oxalato) borate, lithium difluorophosphate, and 1,3-dioxolane.
・ Complex compound 9
A complex compound comprising lithium methyl sulfate, lithium hexafluorophosphate and N-methylpyrrolidone.
・ Complex compound 10
A complex compound comprising lithium methyl sulfate, lithium hexafluorophosphate and 1,3-dioxolan-2-one.
・ Complex compound 11
A complex compound comprising lithium methyl sulfate, lithium hexafluorophosphate and 4-fluoro-1,3-dioxolan-2-one.
・ Complex compound 12
A complex compound comprising lithium methyl sulfate, lithium hexafluorophosphate and 1,3-dioxolane.
・ Complex compound 13
A complex compound comprising lithium methyl sulfate, lithium difluorophosphate and N-methylpyrrolidone.
・ Complex compound 14
A complex compound comprising lithium methyl sulfate, lithium difluorophosphate, and 1,3-dioxolan-2-one.
・ Complex compound 15
A complex compound comprising lithium methyl sulfate, lithium difluorophosphate and 4-fluoro-1,3-dioxolan-2-one.
・ Complex compound 16
A complex compound comprising lithium methyl sulfate, lithium difluorophosphate and 1,3-dioxolane.
Complex compound 17
A complex compound comprising lithium fluorosulfonate, lithium hexafluorophosphate and N-methylpyrrolidone.
Complex compound 18
A complex compound comprising lithium fluorosulfonate, lithium hexafluorophosphate and 1,3-dioxolan-2-one.
Complex compound 19
A complex compound comprising lithium fluorosulfonate, lithium hexafluorophosphate and 4-fluoro-1,3-dioxolan-2-one.
・ Complex compound 20
A complex compound comprising lithium fluorosulfonate, lithium hexafluorophosphate and 1,3-dioxolane.
・ Complex compound 21
A complex compound comprising lithium fluorosulfonate, lithium difluorophosphate and N-methylpyrrolidone.
Complex compound 22
A complex compound comprising lithium fluorosulfonate, lithium difluorophosphate and 1,3-dioxolan-2-one.
Complex compound 23
A complex compound comprising lithium fluorosulfonate, lithium difluorophosphate and 4-fluoro-1,3-dioxolan-2-one.
・ Complex compound 24
A complex compound comprising lithium fluorosulfonate, lithium difluorophosphate and 1,3-dioxolane.
・ Complex compound 25
A complex compound comprising lithium fluorosulfonate, lithium tetrafluoroborate and N-methylpyrrolidone.
・ Complex compound 26
A complex compound comprising lithium fluorosulfonate, lithium tetrafluoroborate and 1,3-dioxolan-2-one.
Complex compound 27
A complex compound comprising lithium fluorosulfonate, lithium tetrafluoroborate and 4-fluoro-1,3-dioxolan-2-one.
Complex compound 28
A complex compound comprising lithium fluorosulfonate, lithium tetrafluoroborate and 1,3-dioxolane.
Complex compound 29
A complex compound comprising lithium trifluoromethanesulfonate, lithium hexafluorophosphate and N-methylpyrrolidone.
・ Complex compound 30
A complex compound comprising lithium trifluoromethanesulfonate, lithium hexafluorophosphate, and 1,3-dioxolan-2-one.
・ Complex compound 31
A complex compound comprising lithium trifluoromethanesulfonate, lithium hexafluorophosphate and 4-fluoro-1,3-dioxolan-2-one.
Complex compound 32
A complex compound comprising lithium trifluoromethanesulfonate, lithium hexafluorophosphate, and 1,3-dioxolane.
Complex compound 33
A complex compound comprising lithium trifluoromethanesulfonate, lithium difluorophosphate, and N-methylpyrrolidone.
・ Complex compound 34
A complex compound comprising lithium trifluoromethanesulfonate, lithium difluorophosphate, and 1,3-dioxolan-2-one.
・ Complex compound 35
A complex compound comprising lithium trifluoromethanesulfonate, lithium difluorophosphate, and 4-fluoro-1,3-dioxolan-2-one.
・ Complex compound 36
A complex compound comprising lithium trifluoromethanesulfonate, lithium difluorophosphate, and 1,3-dioxolane.

  Hereinafter, the structures of complex compounds 1-36 are shown. The following structures (1) to (36) are structures of complex compounds 1 to 36, respectively.

  Among the specific examples, complex compounds 1 to 3, 6, 7, 10 to 12, 14 to 16, 18 to 20, 22 to 24, 26 to 28, 30, 31, 34, and 35 are preferable.

[Example of production method of lithium salt complex compound (Production method A)]
Hereinafter, an example of a method for producing the lithium salt complex compound of the present disclosure (hereinafter also referred to as “Production Method A”) will be shown.

Production method A includes a step of obtaining the lithium salt complex compound of the present disclosure by mixing the first lithium salt, the second lithium salt, and the compound X (hereinafter, also referred to as “mixing step”).
In the mixing step, finally, the three components of the first lithium salt, the second lithium salt and the compound X (hereinafter also simply referred to as “three components”) may be mixed. There are no particular restrictions.
As a mixing method, for example,
A method of mixing the three components at once,
And a method of mixing the three components several times (for example, including a method of first mixing the two components and adding the remaining one component to the obtained mixture and mixing).

In the mixing step, the mixing molar ratio of the second lithium salt to the first lithium salt (second lithium salt / first lithium salt) is 0.2 to 6 from the viewpoint of stably forming the lithium salt complex compound. It is preferable that it is 0.3-4.
When the mixing molar ratio is 0.2 or more, it is easy to avoid a state in which the first lithium salt is excessive. When the mixing molar ratio is 6 or less, it is easy to avoid a state in which the second lithium salt is excessive.

In the mixing step, the mixing molar ratio of compound X to the first lithium salt (compound X / first lithium salt) is preferably 1 to 20 from the viewpoint of stably forming the lithium salt complex compound. 10 is more preferable.
When the mixing molar ratio is 1 or more, it is easy to avoid a state in which the first lithium salt or the second lithium salt is excessive.
When the mixing molar ratio is 20 or less, it is easy to avoid a state in which the compound X becomes excessive.

The mixing of the three components of the first lithium salt, the second lithium salt and the compound X is preferably performed in the presence of a solvent.
As the solvent, it is preferable to use a solvent that can dissolve at least one of the three components from the viewpoint of obtaining a more homogeneous product (lithium salt complex compound).

As the solvent, any solvent can be used as long as it is a non-aqueous solvent and does not inhibit the formation of the target lithium salt complex compound.
Examples of the solvent include acetone, ethyl acetate, dimethoxyethane, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, acetonitrile, dimethyl carbonate, ethyl methyl carbonate, diethyl carbonate, hexane, heptane, octane, nonane, decane, toluene, xylene (ortho , Meta, para), ethylbenzene, butylbenzene, pentylbenzene, hexylbenzene, heptylbenzene, propylbenzene, isopropylbenzene (cumene), cyclohexylbenzene, tetralin, mesitylenemethylcyclopentane, cyclohexane, methylcyclohexane, cycloheptane, cyclooctane, And cyclononane.

The mixing of the three components can be performed under normal pressure or reduced pressure.
The mixing of the three components is preferably performed in an inert atmosphere such as nitrogen or argon from the viewpoint of suppressing the mixing of components (for example, moisture) that inhibit the formation of the lithium salt complex compound.

The temperature when mixing the three components is preferably 20 ° C to 200 ° C, more preferably 20 ° C to 150 ° C, and further preferably 20 ° C to 100 ° C.
When the temperature is 20 ° C. or higher, the formation of the lithium salt complex compound is easily promoted.
When the temperature is 200 ° C. or lower, dissociation of the produced lithium salt complex compound is suppressed, and the production rate is easily improved.

  The mixing time of the three components is preferably 30 minutes to 12 hours, and more preferably 1 hour to 8 hours, from the viewpoint of allowing the reaction to proceed efficiently.

Production method A may include a step of taking out the lithium salt complex compound of the present disclosure obtained in the mixing step (hereinafter also referred to as “takeout step”).
There is no restriction | limiting in particular in operation in a taking-out process.
For example, when the lithium salt complex compound is obtained as a solid in the mixing step, the solid lithium salt complex compound can be taken out without any special treatment.
In the mixing step, when a slurry in which the lithium salt complex compound is dispersed in a solvent is obtained, the lithium salt complex compound can be taken out by removing the solvent from the slurry by separation and / or drying. it can.
In addition, when a solution in which the lithium salt complex compound is dissolved in the solvent is obtained in the mixing step, the lithium salt complex compound is dissolved in the solution by distilling off the solvent from the solution by heat concentration. The lithium salt complex compound can be taken out by adding a non-performing solvent to precipitate the lithium salt complex compound and then removing the solvent by separation and / or drying.

As a drying method in the take-out step, a conventionally known method can be arbitrarily selected and carried out.
For example, a stationary drying method using a shelf dryer; a fluid drying method using a conical dryer; a method using a hot plate, an oven, or the like; a hot or hot air is supplied using a dryer such as a dryer; Method; and the like.

  The pressure for drying the extracted lithium salt complex compound may be either normal pressure or reduced pressure.

The drying temperature is preferably 20 ° C to 200 ° C, more preferably 20 ° C to 150 ° C, and further preferably 20 ° C to 100 ° C.
If the temperature is 20 ° C. or higher, the drying efficiency is good.
When the temperature is 200 ° C. or lower, dissociation of the generated lithium salt complex compound is suppressed, and the lithium salt complex compound can be easily taken out stably.

The lithium salt complex compound taken out in the taking-out step may be used as it is, or for example, dispersed or dissolved in a solvent.
Further, the extracted lithium salt complex compound may be used by mixing with other solid substances.

  The lithium salt complex compound of the present disclosure includes an additive for a lithium battery (preferably an additive for a lithium secondary battery, more preferably an additive for a non-aqueous electrolyte solution of a lithium secondary battery), a reaction reagent, and a synthetic reaction catalyst. It can be usefully used in applications such as electrolytes for various electrochemical devices, doping agents, additives for lubricating oils, and the like.

[Additives for lithium secondary batteries]
The additive for lithium secondary batteries of the present disclosure includes the above-described lithium salt complex compound.
The lithium secondary battery additive of the present disclosure is particularly suitable as an additive for a non-aqueous electrolyte solution of a lithium secondary battery.

Examples of the present disclosure will be described below, but the present disclosure is not limited to the following examples.
In the following, room temperature means 25 ° C.

[Example 1] Complex compound 1 comprising lithium hexafluorophosphate, lithium difluorophosphate and N-methylpyrrolidone
After purging a 100 mL flask equipped with a stirrer, thermometer, gas introduction line, and exhaust line with dry nitrogen gas, 4.56 g (0.03 mol) of lithium hexafluorophosphate and lithium difluorophosphate 3 .24 g (0.03 mol) and 50 g of ethyl acetate were added and stirred at room temperature to dissolve lithium hexafluorophosphate and lithium difluorophosphate. 17.84 g (0.18 mol) of N-methylpyrrolidone was added to the resulting solution and stirred for 1 hour to obtain a reaction solution. Next, while stirring the reaction solution, the pressure in the flask was reduced to 10 kPa or less and the mixture was heated to 60 ° C. to distill off ethyl acetate from the reaction solution. The obtained solid was further dried at 60 ° C. under reduced pressure of 10 kPa or less to obtain 25.64 g of a solid product.

The obtained solid product was dissolved in deuterated dimethyl sulfoxide solvent, and each of ¹ H-NMR analysis and ¹⁹ F-NMR analysis was performed.

Chemical shifts [ppm] and integral values (ratio) of the spectra obtained by ¹ H-NMR analysis and ¹⁹ F-NMR analysis were as follows.

¹ H-NMR: 2.0 ppm (2H), 2.4 ppm (2H), 2.9 ppm (3H), 3.4 ppm (2H).
¹⁹ F-NMR: -72 ppm (3F), -74 ppm (3F). -82 ppm (1F), -85 ppm (1F).

^{From 1} H-NMR, the spectrum pattern of N-methylpyrrolidone was confirmed, and from ¹⁹ F-NMR, a pattern combining the individual spectrum patterns of lithium difluorophosphate and lithium hexafluorophosphate was confirmed.

Further, differential scanning calorimetry (DSC) measurement from room temperature to 600 ° C. was performed on the obtained solid product. In the obtained solid product, an endothermic thermal dissociation behavior having a peak at 198 ° C., which was not observed when each raw material compound was measured alone, was observed.
The endothermic thermal dissociation behavior was observed using a differential scanning calorimeter (DSC220C type) manufactured by Seiko Instruments Inc. The same applies to the second and subsequent embodiments.

  From the above results, it was confirmed that the solid product was complex compound 1 composed of lithium hexafluorophosphate, lithium difluorophosphate, and N-methylpyrrolidone.

[Example 2] Complex compound 2 comprising lithium hexafluorophosphate, lithium difluorophosphate and 1,3-dioxolan-2-one
In the same manner as in Example 1, 17.84 g of N-methylpyrrolidone was changed to 15.85 g (0.18 mol) of 1,3-dioxolan-2-one, and the solid product 23. 64 g was obtained.
The obtained solid product was analyzed and measured in the same manner as in Example 1.
The results are shown below.

¹ H-NMR: 4.5 ppm.
¹⁹ F-NMR: -72 ppm (3F), -74 ppm (3F), -82 ppm (1F), -85 ppm (1F).

^{From 1} H-NMR, the spectrum pattern of 1,3-dioxolan-2-one was confirmed, and from ¹⁹ F-NMR, a pattern combining each of the individual spectrum patterns of lithium difluorophosphate and lithium hexafluorophosphate was obtained. confirmed.
Moreover, as a result of differential scanning calorimetry (DSC) measurement from room temperature to 600 ° C., the obtained solid product has an endothermic thermal dissociation behavior with a peak of 180 ° C. that is not recognized when each raw material compound is measured alone. Observed.

  From the above results, it was confirmed that the solid product was complex compound 2 composed of lithium hexafluorophosphate, lithium difluorophosphate, and 1,3-dioxolan-2-one.

[Example 3] Complex compound 3 comprising lithium hexafluorophosphate, lithium difluorophosphate and 4-fluoro-1,3-dioxolan-2-one
In the same manner as in Example 1, 17.84 g of N-methylpyrrolidone was changed to 19.09 g (0.18 mol) of 4-fluoro-1,3-dioxolan-2-one, and a solid was treated. 26.88 g of product was obtained.
The obtained solid product was analyzed and measured in the same manner as in Example 1.
The results are shown below.

¹ H-NMR: 4.6 ppm (1H), 4.7 ppm (1H), 6.5 ppm (0.5H), 6.6 ppm (0.5H).
¹⁹ F-NMR: -72 ppm (3F), -74 ppm (3F). -82 ppm (1F), -85 ppm (1F), -124 ppm (6F).

¹ H-NMR confirms the spectral pattern of 4-fluoro-1,3-dioxolan-2-one, and ¹⁹ F-NMR confirms lithium difluorophosphate, lithium hexafluorophosphate and 4-fluoro-1,3. A pattern combining the single spectral pattern of each of -dioxolan-2-one was confirmed.
In addition, as a result of differential scanning calorimetry (DSC) measurement from room temperature to 600 ° C., the obtained solid product has an endothermic thermal dissociation behavior with a 118 ° C. peak that is not recognized when each raw material compound is measured alone. Observed.

  From the above results, it was confirmed that the solid product was a complex compound 3 composed of lithium hexafluorophosphate, lithium difluorophosphate, and 4-fluoro-1,3-dioxolan-2-one.

[Example 4] Complex compound 6 comprising lithium bis (oxalato) borate, lithium difluorophosphate and 1,3-dioxolan-2-one
In the same manner as in Example 1, 4.56 g of lithium hexafluorophosphate was changed to 5.81 g (0.03 mol) of lithium bis (oxalato) borate, and 17.84 g of N-methylpyrrolidone was 1 , 3-Dioxolan-2-one was changed to 15.85 g (0.18 mol) to obtain 24.88 g of a solid product.
The obtained solid product was analyzed and measured in the same manner as in Example 1.
The results are shown below.

¹ H-NMR: 4.5 ppm.
¹⁹ F-NMR: -82 ppm, -85 ppm.

In this example, ¹¹ B-NMR analysis was also performed. The chemical shift [ppm] of the spectrum obtained by ¹¹ B-NMR analysis was as follows.
¹¹ B-NMR: 6.5 ppm.

The spectrum pattern of 1,3-dioxolan-2-one was confirmed from ¹ H-NMR, the spectrum pattern of lithium difluorophosphate was confirmed from ¹⁹ F-NMR, and bis (oxalato) borane was confirmed from ¹¹ B-NMR. A spectral pattern of lithium acid was confirmed.
In addition, as a result of differential scanning calorimetry (DSC) measurement from room temperature to 600 ° C., the obtained solid product has no endothermic thermal dissociation behavior at 216 ° C. peak, which is not observed when each raw material compound is measured alone. Was observed.

  From the above results, it was confirmed that the solid product was a complex compound 6 composed of lithium bis (oxalato) borate, lithium difluorophosphate, and 1,3-dioxolan-2-one.

[Example 5] Complex compound 7 comprising lithium bis (oxalato) borate, lithium difluorophosphate and 4-fluoro-1,3-dioxolan-2-one
In the same manner as in Example 1, 4.56 g of lithium hexafluorophosphate was changed to 5.81 g (0.03 mol) of lithium bis (oxalato) borate, and 17.84 g of N-methylpyrrolidone was changed to 4 -Fluoro-1,3-dioxolan-2-one was changed to 19.09 g (0.18 mol) and treated to obtain 28.14 g of a solid product.
The obtained solid product was analyzed and measured in the same manner as in Example 4.
The results are shown below.

¹ H-NMR: 4.6 ppm (1H), 4.7 ppm (1H), 6.5 ppm (0.5H), 6.6 ppm (0.5H).
¹⁹ F-NMR: -82 ppm (1F), -85 ppm (1F), -124 ppm (6F).
¹¹ B-NMR: 6.5 ppm.

¹ H-NMR confirms the spectral pattern of 4-fluoro-1,3-dioxolan-2-one, and ¹⁹ F-NMR confirms lithium difluorophosphate and 4-fluoro-1,3-dioxolan-2-one. As a result, a spectrum pattern of lithium bis (oxalato) borate was confirmed from ¹¹ B-NMR.
In addition, as a result of differential scanning calorimetry (DSC) measurement from room temperature to 600 ° C., the obtained solid product has an endothermic thermal dissociation behavior of a 168 ° C. peak that is not recognized when each raw material compound is measured alone. Observed.

  From the above results, it was confirmed that the solid product was complex compound 7 composed of lithium bis (oxalato) borate, lithium difluorophosphate, and 4-fluoro-1,3-dioxolan-2-one.

[Example 6] Complex compound 10 comprising lithium methyl sulfate, lithium hexafluorophosphate and 1,3-dioxolan-2-one
In the same manner as in Example 1, 3.24 g of lithium difluorophosphate was changed to 3.54 g (0.03 mol) of lithium methyl sulfate, and 17.84 g of N-methylpyrrolidone was changed to 1,3-dioxolane. The treatment was performed by changing the amount to 15.85 g (0.18 mol) of 2-one to obtain 23.94 g of a solid product.
The obtained solid product was analyzed and measured in the same manner as in Example 1.
The results are shown below.

¹ H-NMR: 3.5 ppm (3H), 4.5 ppm (24H).
¹⁹ F-NMR: -72 ppm, -74 ppm.

¹ H-NMR confirmed the combined pattern of each of lithium methyl sulfate and 1,3-dioxolan-2-one, and ¹⁹ F-NMR confirmed the spectral pattern of lithium hexafluorophosphate. It was done.
In addition, as a result of differential scanning calorimetry (DSC) measurement from room temperature to 600 ° C., the obtained solid product has an endothermic thermal dissociation behavior of a 246 ° C. peak that is not recognized when each raw material compound is measured alone. Observed.

  From the above results, it was confirmed that the solid product was a complex compound 10 composed of lithium methyl sulfate, lithium hexafluorophosphate, and 1,3-dioxolan-2-one.

[Example 7] Complex compound 11 consisting of lithium methyl sulfate, lithium hexafluorophosphate and 4-fluoro-1,3-dioxolan-2-one
In the same manner as in Example 1, 3.24 g of lithium difluorophosphate was changed to 3.54 g (0.03 mol) of lithium methyl sulfate, and 17.84 g of N-methylpyrrolidone was changed to 4-fluoro-1, The treatment was changed to 19.09 g (0.18 mol) of 3-dioxolan-2-one to obtain 27.18 g of a solid product.
The obtained solid product was analyzed and measured in the same manner as in Example 1.
The results are shown below.

¹ H-NMR: 3.5 ppm (3H), 4.6 ppm (6H), 4.7 ppm (6H), 6.5 ppm (3H), 6.6 ppm (3H).
¹⁹ F-NMR: -72 ppm (3F), -74 ppm (3F), -124 ppm (6F).

¹ H-NMR confirmed the combined pattern of each of lithium methyl sulfate and 4-fluoro-1,3-dioxolan-2-one, and ¹⁹ F-NMR confirmed that lithium hexafluorophosphate and A pattern combining the single spectral patterns of each of 4-fluoro-1,3-dioxolan-2-one was confirmed.
In addition, as a result of differential scanning calorimetry (DSC) measurement from room temperature to 600 ° C., the obtained solid product has an endothermic thermal dissociation behavior of a 188 ° C. peak that is not recognized when each raw material compound is measured alone. Observed.

  From the above results, it was confirmed that the solid product was a complex compound 11 composed of lithium methyl sulfate, lithium hexafluorophosphate, and 4-fluoro-1,3-dioxolan-2-one.

[Example 8] Complex compound 12 comprising lithium methyl sulfate, lithium hexafluorophosphate and 1,3-dioxolane
In the same manner as in Example 1, 3.24 g of lithium difluorophosphate was changed to 3.54 g (0.03 mol) of lithium methyl sulfate, and 17.84 g of N-methylpyrrolidone was replaced with 1,3-dioxolane 13 The treatment was changed to .33 g (0.18 mol) to obtain 21.42 g of a solid product.
The obtained solid product was analyzed and measured in the same manner as in Example 1.
The results are shown below.

¹ H-NMR: 3.5 ppm (3H), 4.2 ppm (24H), 5.6 ppm (12H).
¹⁹ F-NMR: -72 ppm, -74 ppm.

^{From 1} H-NMR, a pattern combining the single spectral patterns of each of lithium methyl sulfate and 1,3-dioxolane was confirmed, and from ¹⁹ F-NMR, the spectral pattern of lithium hexafluorophosphate was confirmed.
In addition, as a result of differential scanning calorimetry (DSC) measurement from room temperature to 600 ° C., the obtained solid product has an endothermic thermal dissociation behavior of a 248 ° C. peak that is not observed when each raw material compound is measured alone. Observed.

  From the above results, it was confirmed that the solid product was the complex compound 12 composed of lithium methyl sulfate, lithium hexafluorophosphate, and 1,3-dioxolane.

[Example 9] Complex compound 14 consisting of lithium methyl sulfate, lithium difluorophosphate and 1,3-dioxolan-2-one
In the same manner as in Example 1, 4.56 g of lithium hexafluorophosphate was changed to 3.54 g (0.03 mol) of lithium methyl sulfate, and 17.84 g of N-methylpyrrolidone was replaced with 1,3-dioxolane. The treatment was carried out by changing the amount to 15.85 g (0.18 mol) of 2-one to obtain 22.63 g of a solid product.
The obtained solid product was analyzed and measured in the same manner as in Example 1.
The results are shown below.

¹ H-NMR: 3.5 ppm (3H), 4.5 ppm (24H).
¹⁹ F-NMR: -82 ppm, -85 ppm.

¹ H-NMR confirmed the combined pattern of lithium methyl sulfate and 1,3-dioxolan-2-one, and ¹⁹ F-NMR confirmed the spectral pattern of lithium difluorophosphate. It was.
Moreover, as a result of differential scanning calorimetry (DSC) measurement from room temperature to 600 ° C., the obtained solid product has an endothermic thermal dissociation behavior of a 279 ° C. peak that is not recognized when each raw material compound is measured alone. Observed.

  From the above results, it was confirmed that the solid product was a complex compound 14 composed of lithium methyl sulfate, lithium difluorophosphate, and 1,3-dioxolan-2-one.

[Example 10] Complex 15 consisting of lithium methyl sulfate, lithium difluorophosphate and 4-fluoro-1,3-dioxolan-2-one
In the same manner as in Example 1, 4.56 g of lithium hexafluorophosphate was changed to 3.54 g (0.03 mol) of lithium methyl sulfate, and 17.84 g of N-methylpyrrolidone was changed to 4-fluoro-1 , 3-Dioxolan-2-one 19.09 g (0.18 mol) was changed to obtain 25.86 g of a solid product.
The obtained solid product was analyzed and measured in the same manner as in Example 1.
The results are shown below.

¹ H-NMR: 3.5 ppm (3H), 4.6 ppm (6H), 4.7 ppm (6H), 6.5 ppm (3H), 6.6 ppm (3H).
¹⁹ F-NMR: -82 ppm (1F), -85 ppm (1F), -124 ppm (6F).

¹ H-NMR confirmed the combined pattern of each of lithium methyl sulfate and 4-fluoro-1,3-dioxolan-2-one, and ¹⁹ F-NMR confirmed that lithium difluorophosphate and 4 A pattern combining the spectrum pattern of -fluoro-1,3-dioxolan-2-one alone was confirmed.
Further, as a result of differential scanning calorimetry (DSC) measurement from room temperature to 600 ° C., the obtained solid product has an endothermic thermal dissociation behavior with a peak of 234 ° C. that is not observed when each raw material compound is measured alone. Observed.

  From the above results, it was confirmed that the solid product was a complex compound 15 composed of lithium methyl sulfate, lithium difluorophosphate, and 4-fluoro-1,3-dioxolan-2-one.

[Example 11] Complex compound 16 consisting of lithium methyl sulfate, lithium difluorophosphate and 1,3-dioxolane
In the same manner as in Example 1, 4.56 g of lithium hexafluorophosphate was changed to 3.54 g (0.03 mol) of lithium methyl sulfate, and 17.84 g of N-methylpyrrolidone was replaced with 1,3-dioxolane. The treatment was changed to 13.33 g (0.18 mol) to obtain 20.09 g of a solid product.
The obtained solid product was analyzed and measured in the same manner as in Example 1.
The results are shown below.

¹ H-NMR: 3.5 ppm (3H), 4.2 ppm (24H), 5.6 ppm (12H).
¹⁹ F-NMR: -82 ppm, -85 ppm.

¹ H-NMR confirmed the combined pattern of each of lithium methyl sulfate and 1,3-dioxolane, and ¹⁹ F-NMR confirmed the spectral pattern of lithium difluorophosphate.
In addition, as a result of differential scanning calorimetry (DSC) measurement from room temperature to 600 ° C., the obtained solid product has an endothermic thermal dissociation behavior of a 292 ° C. peak that is not observed when each raw material compound is measured alone. Observed.

  From the above results, it was confirmed that the solid product was a complex compound 16 composed of lithium methyl sulfate, lithium difluorophosphate, and 1,3-dioxolane.

[Example 12] Complex compound 18 comprising lithium fluorosulfonate, lithium hexafluorophosphate and 1,3-dioxolan-2-one
In the same manner as in Example 1, 3.24 g of lithium difluorophosphate was changed to 3.18 g (0.03 mol) of lithium fluorosulfonate, and 17.84 g of N-methylpyrrolidone was changed to 1,3-dioxolane. The treatment was performed by changing the amount to 15.85 g (0.18 mol) of 2-one to obtain 23.58 g of a solid product.
The obtained solid product was analyzed and measured in the same manner as in Example 1.
The results are shown below.

¹ H-NMR: 4.5 ppm.
¹⁹ F-NMR: 40 ppm (1F), -72 ppm (3F), -74 ppm (3F).

^{From 1} H-NMR, the spectrum pattern of 1,3-dioxolan-2-one was confirmed, and from ¹⁹ F-NMR, a pattern combining each of the individual spectrum patterns of lithium fluorosulfonate and lithium hexafluorophosphate was obtained. confirmed.
Further, as a result of differential scanning calorimetry (DSC) measurement from room temperature to 600 ° C., the obtained solid product has an endothermic thermal dissociation behavior with a 172 ° C. peak that is not observed when each raw material compound is measured alone. Observed.

  From the above results, it was confirmed that the solid product was a complex compound 18 composed of lithium fluorosulfonate, lithium hexafluorophosphate, and 1,3-dioxolan-2-one.

[Example 13] Complex compound 19 comprising lithium fluorosulfonate, lithium hexafluorophosphate and 4-fluoro-1,3-dioxolan-2-one
In the same manner as in Example 1, 3.24 g of lithium difluorophosphate was changed to 3.18 g (0.03 mol) of lithium fluorosulfonate, and 17.84 g of N-methylpyrrolidone was changed to 4-fluoro-1 , 3-Dioxolan-2-one 19.09 g (0.18 mol) was changed to give 26.82 g of a solid product.
The obtained solid product was analyzed and measured in the same manner as in Example 1.
The results are shown below.

¹ H-NMR: 4.6 ppm (1H), 4.7 ppm (1H), 6.5 ppm (0.5H), 6.6 ppm (0.5H).
¹⁹ F-NMR: 40 ppm (1F), -72 ppm (3F), -74 ppm (3F), -124 ppm (6F).

¹ H-NMR confirmed the spectral pattern of 4-fluoro-1,3-dioxolan-2-one, and ¹⁹ F-NMR confirmed lithium fluorosulfonate, lithium hexafluorophosphate and 4-fluoro-1,3. A pattern combining the single spectral pattern of each of -dioxolan-2-one was confirmed.
Further, as a result of differential scanning calorimetry (DSC) measurement from room temperature to 600 ° C., the obtained solid product has an endothermic thermal dissociation behavior with a 120 ° C. peak that is not observed when each raw material compound is measured alone. Observed.

  From the above results, it was confirmed that the solid product was a complex compound 19 composed of lithium fluorosulfonate, lithium hexafluorophosphate, and 4-fluoro-1,3-dioxolan-2-one.

[Example 14] Complex compound 20 comprising lithium fluorosulfonate, lithium hexafluorophosphate and 1,3-dioxolane
In the same manner as in Example 1, 3.24 g of lithium difluorophosphate was changed to 3.18 g (0.03 mol) of lithium fluorosulfonate, and 17.84 g of N-methylpyrrolidone was changed to 1,3-dioxolane. The treatment was changed to 6.67 g (0.09 mol) to obtain 14.40 g of a solid product.
The obtained solid product was analyzed and measured in the same manner as in Example 1.
The results are shown below.

¹ H-NMR: 4.2 ppm (4H), 5.6 ppm (2H).
¹⁹ F-NMR: 40 ppm (1F), -72 ppm (3F), -74 ppm (3F).

^{From 1} H-NMR, a spectrum pattern of 1,3-dioxolane was confirmed, and from ¹⁹ F-NMR, a pattern combining each spectrum pattern of lithium fluorosulfonate and lithium hexafluorophosphate was confirmed.
In addition, as a result of differential scanning calorimetry (DSC) measurement from room temperature to 600 ° C., the obtained solid product has an endothermic thermal dissociation behavior of a 188 ° C. peak that is not recognized when each raw material compound is measured alone. Observed.

  From the above results, it was confirmed that the solid product was a complex compound 20 composed of lithium fluorosulfonate, lithium hexafluorophosphate, and 1,3-dioxolane.

[Example 15] Complex compound 22 consisting of lithium fluorosulfonate, lithium difluorophosphate and 1,3-dioxolan-2-one
In the same manner as in Example 1, 4.56 g of lithium hexafluorophosphate was changed to 3.18 g (0.03 mol) of lithium fluorosulfonate, and 17.84 g of N-methylpyrrolidone was changed to 1,3- The treatment was changed to 15.85 g (0.18 mol) of dioxolan-2-one to obtain 22.25 g of a solid product.
The obtained solid product was analyzed and measured in the same manner as in Example 1.
The results are shown below.

¹ H-NMR: 4.5 ppm.
¹⁹ F-NMR: 40 ppm (1F), -82 ppm (1F), -85 ppm (1F).

¹ H-NMR confirmed the spectrum pattern of 1,3-dioxolan-2-one, and ¹⁹ F-NMR confirmed the combined pattern of each of lithium fluorosulfonate and lithium difluorophosphate. It was done.
In addition, as a result of differential scanning calorimetry (DSC) measurement from room temperature to 600 ° C., the obtained solid product has an endothermic thermal dissociation behavior with a peak of 223 ° C. that is not recognized when each raw material compound is measured alone. Observed.

  From the above results, it was confirmed that the solid product was a complex compound 22 composed of lithium fluorosulfonate, lithium difluorophosphate, and 1,3-dioxolan-2-one.

[Example 16] Complex compound 23 consisting of lithium fluorosulfonate, lithium difluorophosphate and 4-fluoro-1,3-dioxolan-2-one
In the same manner as in Example 1, 4.56 g of lithium hexafluorophosphate was changed to 3.18 g (0.03 mol) of lithium fluorosulfonate, and 17.84 g of N-methylpyrrolidone was changed to 4-fluoro- The treatment was changed to 19.09 g (0.18 mol) of 1,3-dioxolan-2-one, and 25.50 g of a solid product was obtained.
The obtained solid product was analyzed and measured in the same manner as in Example 1.
The results are shown below.

¹ H-NMR: 4.6 ppm (1H), 4.7 ppm (1H), 6.5 ppm (0.5H), 6.6 ppm (0.5H).
¹⁹ F-NMR: 40 ppm (1F), -82 ppm (1F), -85 ppm (1F), -124 ppm (6F).

¹ H-NMR confirmed the spectral pattern of 4-fluoro-1,3-dioxolan-2-one, and ¹⁹ F-NMR confirmed that lithium fluorosulfonate, lithium difluorophosphate and 4-fluoro-1,3- A pattern combining each single spectral pattern of dioxolan-2-one was confirmed.
Moreover, as a result of differential scanning calorimetry (DSC) measurement from room temperature to 600 ° C., the obtained solid product has an endothermic thermal dissociation behavior with a peak of 160 ° C. that is not recognized when each raw material compound is measured alone. Observed.

  From the above results, it was confirmed that the solid product was a complex compound 23 composed of lithium fluorosulfonate, lithium difluorophosphate, and 4-fluoro-1,3-dioxolan-2-one.

[Example 17] Complex compound 24 comprising lithium fluorosulfonate, lithium difluorophosphate and 1,3-dioxolane
In the same manner as in Example 1, 4.56 g of lithium hexafluorophosphate was changed to 3.18 g (0.03 mol) of lithium fluorosulfonate, and 17.84 g of N-methylpyrrolidone was changed to 1,3- The treatment was changed to 6.67 g (0.09 mol) of dioxolane to obtain 13.07 g of a solid product.
The obtained solid product was analyzed and measured in the same manner as in Example 1.
The results are shown below.

¹ H-NMR: 4.2 ppm (4H), 5.6 ppm (2H).
¹⁹ F-NMR: 40 ppm (1F), -82 ppm (1F), -85 ppm (1F).

^{From 1} H-NMR, the spectrum pattern of 1,3-dioxolane was confirmed, and from ¹⁹ F-NMR, a pattern combining each of the individual spectrum patterns of lithium fluorosulfonate and lithium difluorophosphate was confirmed.
Further, as a result of differential scanning calorimetry (DSC) measurement from room temperature to 600 ° C., the obtained solid product has an endothermic thermal dissociation behavior with a peak of 198 ° C. that is not observed when each raw material compound is measured alone. Observed.

  From the above results, it was confirmed that the solid product was a complex compound 24 composed of lithium fluorosulfonate, lithium difluorophosphate, and 1,3-dioxolane.

[Example 18] Complex compound 26 consisting of lithium fluorosulfonate, lithium tetrafluoroborate and 1,3-dioxolan-2-one
In the same manner as in Example 1, 4.56 g of lithium hexafluorophosphate was added to 3.18 g (0.03 mol) of lithium fluorosulfonate, and 3.24 g of lithium difluorophosphate was added to lithium tetrafluoroborate. It was changed to 81 g (0.03 mol), and 17.84 g of N-methylpyrrolidone was changed to 15.85 g (0.18 mol) of 1,3-dioxolan-2-one to carry out the treatment. Got.
The obtained solid product was analyzed and measured in the same manner as in Example 4.
The results are shown below.

¹ H-NMR: 4.5 ppm.
¹⁹ F-NMR: 40 ppm (1F), −153 ppm (4F).
¹¹ B-NMR: -2.4 ppm.

^{From 1} H-NMR, the spectrum pattern of 1,3-dioxolan-2-one was confirmed, and from ¹⁹ F-NMR, a pattern combining each of the individual spectrum patterns of lithium fluorosulfonate and lithium tetrafluoroborate was obtained. The spectrum pattern of lithium tetrafluoroborate was confirmed from ¹¹ B-NMR.
In addition, as a result of differential scanning calorimetry (DSC) measurement from room temperature to 600 ° C., the obtained solid product has an endothermic thermal dissociation behavior of 212 ° C. peak that is not recognized when each raw material compound is measured alone. Observed.

  From the above results, it was confirmed that the solid product was a complex compound 26 composed of lithium fluorosulfonate, lithium tetrafluoroborate, and 1,3-dioxolan-2-one.

[Example 19] Complex compound 27 composed of lithium fluorosulfonate, lithium tetrafluoroborate and 4-fluoro-1,3-dioxolan-2-one
In the same manner as in Example 1, 4.56 g of lithium hexafluorophosphate was added to 3.18 g (0.03 mol) of lithium fluorosulfonate, and 3.24 g of lithium difluorophosphate was added to lithium tetrafluoroborate. The amount was changed to 81 g (0.03 mol), and 17.84 g of N-methylpyrrolidone was changed to 19.09 g (0.18 mol) of 4-fluoro-1,3-dioxolan-2-one, and a solid was produced. 25.06 g of product was obtained.
The obtained solid product was analyzed and measured in the same manner as in Example 4.
The results are shown below.

¹ H-NMR: 4.6 ppm (1H), 4.7 ppm (1H), 6.5 ppm (0.5H), 6.6 ppm (0.5H).
¹⁹ F-NMR: 40 ppm (1F), -124 ppm (6F), -153 ppm (4F).
¹¹ B-NMR: -2.4 ppm.

¹ H-NMR confirmed the spectral pattern of 4-fluoro-1,3-dioxolan-2-one, and ¹⁹ F-NMR confirmed lithium fluorosulfonate, lithium tetrafluoroborate and 4-fluoro-1,3. -The pattern which combined each single spectrum pattern of -dioxolan-2-one was confirmed, and the spectrum pattern of the lithium tetrafluoroborate was confirmed from ¹¹ B-NMR.
In addition, as a result of differential scanning calorimetry (DSC) measurement from room temperature to 600 ° C., the obtained solid product has an endothermic thermal dissociation behavior with a peak of 157 ° C. which is not recognized when each raw material compound is measured alone. Observed.

  From the above results, it was confirmed that the solid product was a complex compound 27 composed of lithium fluorosulfonate, lithium tetrafluoroborate, and 4-fluoro-1,3-dioxolan-2-one.

[Example 20] Complex compound 28 composed of lithium fluorosulfonate, lithium tetrafluoroborate and 1,3-dioxolane
In the same manner as in Example 1, 4.56 g of lithium hexafluorophosphate was added to 3.18 g (0.03 mol) of lithium fluorosulfonate, and 3.24 g of lithium difluorophosphate was added to lithium tetrafluoroborate. The amount was changed to 81 g (0.03 mol), and 17.84 g of N-methylpyrrolidone was changed to 6.67 g (0.09 mol) of 1,3-dioxolane to obtain 12.66 g of a solid product.
The obtained solid product was analyzed and measured in the same manner as in Example 4.
The results are shown below.

¹ H-NMR: 4.2 ppm (4H), 5.6 ppm (2H).
¹⁹ F-NMR: 40 ppm (1F), −153 ppm (4F).
¹¹ B-NMR: -2.4 ppm.

¹ H-NMR confirmed the spectrum pattern of 1,3-dioxolane, and ¹⁹ F-NMR confirmed the combined pattern of each of lithium fluorosulfonate and lithium tetrafluoroborate. ¹¹ From B-NMR, the spectrum pattern of lithium tetrafluoroborate was confirmed.
Further, as a result of differential scanning calorimetry (DSC) measurement from room temperature to 600 ° C., the obtained solid product has an endothermic thermal dissociation behavior with a peak at 214 ° C. that is not recognized when each raw material compound is measured alone. Observed.

  From the above results, it was confirmed that the solid product was a complex compound 28 composed of lithium fluorosulfonate, lithium tetrafluoroborate, and 1,3-dioxolane.

[Example 21] Complex compound 30 comprising lithium trifluoromethanesulfonate, lithium hexafluorophosphate and 1,3-dioxolan-2-one
In the same manner as in Example 1, 3.24 g of lithium difluorophosphate was changed to 4.68 g (0.03 mol) of lithium trifluoromethanesulfonate, and 17.84 g of N-methylpyrrolidone was 1,3- The treatment was changed to 15.85 g (0.18 mol) of dioxolan-2-one, and 25.09 g of a solid product was obtained.
The obtained solid product was analyzed and measured in the same manner as in Example 1.
The results are shown below.

¹ H-NMR: 4.5 ppm.
¹⁹ F-NMR: -72 ppm (3F), -74 ppm (3F), -78 ppm (3F).

^{From 1} H-NMR, a spectrum pattern of 1,3-dioxolan-2-one was confirmed, and from ¹⁹ F-NMR, a combined pattern of each single spectrum pattern of lithium trifluoromethanesulfonate and lithium hexafluorophosphate Was confirmed.
Further, as a result of differential scanning calorimetry (DSC) measurement from room temperature to 600 ° C., the obtained solid product has an endothermic thermal dissociation behavior with a 205 ° C. peak that is not recognized when each raw material compound is measured alone. Observed.

  From the above results, it was confirmed that the solid product was a complex compound 30 composed of lithium trifluoromethanesulfonate, lithium hexafluorophosphate, and 1,3-dioxolan-2-one.

[Example 22] Complex compound 31 composed of lithium trifluoromethanesulfonate, lithium hexafluorophosphate and 4-fluoro-1,3-dioxolan-2-one
In the same manner as in Example 1, 3.24 g of lithium difluorophosphate was changed to 4.68 g (0.03 mol) of lithium trifluoromethanesulfonate, and 17.84 g of N-methylpyrrolidone was changed to 4-fluoro- The treatment was changed to 19.09 g (0.18 mol) of 1,3-dioxolan-2-one, and 28.31 g of a solid product was obtained.
The obtained solid product was analyzed and measured in the same manner as in Example 1.
The results are shown below.

¹ H-NMR: 4.6 ppm (1H), 4.7 ppm (1H), 6.5 ppm (0.5H), 6.6 ppm (0.5H).
¹⁹ F-NMR: -72 ppm (3F), -74 ppm (3F), -78 ppm (3F), -124 ppm (6F).

^{From 1} H-NMR, the spectrum pattern of 4-fluoro-1,3-dioxolan-2-one was confirmed. From ¹⁹ F-NMR, lithium trifluoromethanesulfonate, lithium hexafluorophosphate and 4-fluoro-1, A pattern combining each single spectral pattern of 3-dioxolan-2-one was confirmed.
Further, as a result of differential scanning calorimetry (DSC) measurement from room temperature to 600 ° C., the obtained solid product has an endothermic thermal dissociation behavior with a 205 ° C. peak that is not recognized when each raw material compound is measured alone. Observed.

  From the above results, it was confirmed that the solid product was a complex compound 31 composed of lithium trifluoromethanesulfonate, lithium hexafluorophosphate, and 4-fluoro-1,3-dioxolan-2-one.

[Example 23] Complex compound 34 composed of lithium trifluoromethanesulfonate, lithium difluorophosphate and 1,3-dioxolan-2-one
In the same manner as in Example 1, 4.56 g of lithium hexafluorophosphate was changed to 4.68 g (0.03 mol) of lithium trifluoromethanesulfonate, and 17.84 g of N-methylpyrrolidone was changed to 1,3. -Dioxolan-2-one was changed to 15.85 g (0.18 mol) and treated to obtain 23.77 g of a solid product.
The obtained solid product was analyzed and measured in the same manner as in Example 1.
The results are shown below.

¹ H-NMR: 4.5 ppm.
¹⁹ F-NMR: -78 ppm (3F), -82 ppm (1F), -85 ppm (1F).

^{From 1} H-NMR, a spectrum pattern of 1,3-dioxolan-2-one was confirmed, and from ¹⁹ F-NMR, a pattern combining each of the individual spectrum patterns of lithium trifluoromethanesulfonate and lithium difluorophosphate was obtained. confirmed.
In addition, as a result of differential scanning calorimetry (DSC) measurement from room temperature to 600 ° C., the obtained solid product has an endothermic thermal dissociation behavior of a 265 ° C. peak that is not recognized when each raw material compound is measured alone. Observed.

  From the above results, it was confirmed that the solid product was a complex compound 34 composed of lithium trifluoromethanesulfonate, lithium difluorophosphate, and 1,3-dioxolan-2-one.

[Example 24] Complex compound 35 consisting of lithium trifluoromethanesulfonate, lithium difluorophosphate and 4-fluoro-1,3-dioxolan-2-one
In the same manner as in Example 1, 4.56 g of lithium hexafluorophosphate was changed to 4.68 g (0.03 mol) of lithium trifluoromethanesulfonate, and 17.84 g of N-methylpyrrolidone was changed to 4-fluoro The change was made to 19.09 g (0.18 mol) of -1,3-dioxolan-2-one, and 27.00 g of a solid product was obtained.
The obtained solid product was analyzed and measured in the same manner as in Example 1.
The results are shown below.

¹ H-NMR: 4.6 ppm (1H), 4.7 ppm (1H), 6.5 ppm (0.5H), 6.6 ppm (0.5H).
¹⁹ F-NMR: -78 ppm (3F), -82 ppm (1F), -85 ppm (1F), -124 ppm (6F).

¹ H-NMR confirms the spectral pattern of 4-fluoro-1,3-dioxolan-2-one, and ¹⁹ F-NMR confirms lithium trifluoromethanesulfonate, lithium difluorophosphate and 4-fluoro-1,3. A pattern combining the single spectral pattern of each of -dioxolan-2-one was confirmed.
Further, as a result of differential scanning calorimetry (DSC) measurement from room temperature to 600 ° C., the obtained solid product has an endothermic thermal dissociation behavior with a peak of 198 ° C. that is not observed when each raw material compound is measured alone. Observed.

  From the above results, it was confirmed that the solid product was a complex compound 35 composed of lithium trifluoromethanesulfonate, lithium difluorophosphate, and 4-fluoro-1,3-dioxolan-2-one.

As shown above, in each Example, a novel lithium salt complex compound was obtained.
In addition, the lithium salt complex compound obtained in each example shows an endothermic thermal dissociation behavior at a temperature at which each of the raw material compounds (first lithium salt, second lithium salt, and compound X) is not recognized alone. It was. That is, it was confirmed that the lithium salt complex compound obtained in each Example was not a simple mixture of raw material compounds but a complex compound and a compound having excellent thermal stability.

Claims (5)

A halogen atom, an alkyl group optionally substituted with a halogen atom, an alkoxy group optionally substituted with a halogen atom, an alkenyl group optionally substituted with a halogen atom, an alkynyl group optionally substituted with a halogen atom In the case where at least one substituent selected from the group consisting of a cyclic ester group, an oxalato group, and an aryl group, which may be substituted with at least one of a halogen atom and an alkyl group, is the substituent L,
Lithium phosphate salt A1 having the substituent L directly bonded to a phosphorus atom, lithium borate salt B1 having the substituent L directly bonded to a boron atom, sulfonic acid having the substituent L directly bonded to a sulfur atom One selected from the group consisting of a lithium salt C1, a lithium sulfate salt D1 having the substituent L directly bonded to a sulfur atom, and a sulfonylimidic acid lithium salt E1 having the substituent L directly bonded to a sulfur atom A first lithium salt;
Lithium phosphate A2 having a fluorine atom directly bonded to a phosphorus atom, lithium borate B2 having a fluorine atom directly bonded to a boron atom, and lithium sulfonate C2 having a fluorine atom directly bonded to a sulfur atom A second lithium salt which is one selected from the group;
Compound X, which is one selected from compounds represented by any one of the following formulas (I) to (V):
A lithium salt complex compound (except when the first lithium salt and the second lithium salt are the same compound).

[In the formula (I), R ¹ is a hydrogen atom, an alkyl group optionally substituted with a halogen atom, an alkenyl group optionally substituted with a halogen atom, an alkynyl group optionally substituted with a halogen atom, Or an aryl group,
R ² is selected from the group consisting of a halogen atom, an alkyl group optionally substituted with a halogen atom, an alkenyl group optionally substituted with a halogen atom, and an alkynyl group optionally substituted with a halogen atom. It represents an alkylene group having 2 to 9 carbon atoms which may be substituted with at least one substituent.
In formula (II), R ³ and R ⁴ are each independently a hydrogen atom, an alkyl group optionally substituted with a halogen atom, an alkenyl group optionally substituted with a halogen atom, or a halogen atom. An alkynyl group or an aryl group,
R ⁵ is selected from the group consisting of a halogen atom, an alkyl group optionally substituted with a halogen atom, an alkenyl group optionally substituted with a halogen atom, and an alkynyl group optionally substituted with a halogen atom. It represents an alkylene group having 2 to 9 carbon atoms which may be substituted with at least one substituent.
In the formula (III), R ⁶ is a halogen atom, an alkyl group which may be substituted with a halogen atom, an alkenyl group which may be substituted with a halogen atom, or an alkynyl group which may be substituted with a halogen atom. Represents an alkylene group having 2 to 9 carbon atoms which may be substituted with at least one substituent selected from the group consisting of
In the formula (IV), R ⁷ is a halogen atom, an alkyl group that may be substituted with a halogen atom, an alkenyl group that may be substituted with a halogen atom, or an alkynyl group that may be substituted with a halogen atom. Represents an alkylene group having 2 to 9 carbon atoms which may be substituted with at least one substituent selected from the group consisting of
In the formula (V), R ⁸ is a halogen atom, an alkyl group that may be substituted with a halogen atom, an alkenyl group that may be substituted with a halogen atom, or an alkynyl group that may be substituted with a halogen atom. Represents an alkylene group having 2 to 9 carbon atoms which may be substituted with at least one substituent selected from the group consisting of ] The first lithium salt is lithium difluorophosphate, lithium hexafluorophosphate, lithium tetrafluoroborate, lithium bis (oxalato) borate, lithium trifluoromethanesulfonate, lithium methylsulfate, lithium benzenesulfonate, fluorosulfonic acid Is one selected from the group consisting of lithium, lithium bis (trifluoromethanesulfonyl) imide, lithium bis (fluorosulfonyl) imide, and lithium bis (perfluoroethylsulfonyl) imide,
The second lithium salt is one selected from the group consisting of lithium difluorophosphate, lithium hexafluorophosphate, lithium tetrafluoroborate, and lithium fluorosulfonate,
Compound X is N-methylpyrrolidone, N-vinylpyrrolidone, 1,3-dimethyl-2-imidazolidinone, 1,3-dioxolan-2-one, 4-methyl-1,3-dioxolan-2-one From the group consisting of 4-fluoro-1,3-dioxolan-2-one, 1,3-dioxolane, 1,3-dioxane, and 2-fluoro-1,3,2-dioxaphosphorinane-2-oxide The lithium salt complex compound according to claim 1, which is one selected. The first lithium salt is a group consisting of lithium difluorophosphate, lithium hexafluorophosphate, lithium tetrafluoroborate, lithium bis (oxalato) borate, lithium trifluoromethanesulfonate, lithium fluorosulfonate, and lithium methylsulfate. 1 type selected from
The second lithium salt is one selected from the group consisting of lithium difluorophosphate, lithium hexafluorophosphate, lithium tetrafluoroborate, and lithium fluorosulfonate,
Compound X is one selected from the group consisting of N-methylpyrrolidone, 1,3-dioxolan-2-one, 4-fluoro-1,3-dioxolan-2-one, and 1,3-dioxolane The lithium salt complex compound according to claim 1 or 2. A complex compound comprising lithium hexafluorophosphate, lithium difluorophosphate and N-methylpyrrolidone,
A complex compound comprising lithium hexafluorophosphate, lithium difluorophosphate and 1,3-dioxolan-2-one,
A complex compound comprising lithium hexafluorophosphate, lithium difluorophosphate and 4-fluoro-1,3-dioxolan-2-one,
A complex compound comprising lithium bis (oxalato) borate, lithium difluorophosphate and 1,3-dioxolan-2-one,
A complex compound comprising lithium bis (oxalato) borate, lithium difluorophosphate and 4-fluoro-1,3-dioxolan-2-one,
A complex compound comprising lithium methyl sulfate, lithium hexafluorophosphate and 1,3-dioxolan-2-one,
A complex compound comprising lithium methyl sulfate, lithium hexafluorophosphate and 4-fluoro-1,3-dioxolan-2-one,
A complex compound comprising lithium methyl sulfate, lithium hexafluorophosphate and 1,3-dioxolane,
A complex compound comprising lithium methyl sulfate, lithium difluorophosphate and 1,3-dioxolan-2-one,
A complex compound comprising lithium methyl sulfate, lithium difluorophosphate and 4-fluoro-1,3-dioxolan-2-one,
A complex compound comprising lithium methyl sulfate, lithium difluorophosphate and 1,3-dioxolane;
A complex compound comprising lithium trifluoromethanesulfonate, lithium hexafluorophosphate and 1,3-dioxolan-2-one,
A complex compound comprising lithium trifluoromethanesulfonate, lithium hexafluorophosphate and 4-fluoro-1,3-dioxolan-2-one;
A complex compound comprising lithium trifluoromethanesulfonate, lithium difluorophosphate and 1,3-dioxolan-2-one,
A complex compound comprising lithium trifluoromethanesulfonate, lithium difluorophosphate and 4-fluoro-1,3-dioxolan-2-one,
A complex compound comprising lithium fluorosulfonate, lithium hexafluorophosphate and 1,3-dioxolan-2-one,
A complex compound comprising lithium fluorosulfonate, lithium hexafluorophosphate and 4-fluoro-1,3-dioxolan-2-one,
A complex compound comprising lithium fluorosulfonate, lithium hexafluorophosphate and 1,3-dioxolane,
A complex compound comprising lithium fluorosulfonate, lithium difluorophosphate and 1,3-dioxolan-2-one,
A complex compound comprising lithium fluorosulfonate, lithium difluorophosphate and 4-fluoro-1,3-dioxolan-2-one,
A complex compound comprising lithium fluorosulfonate, lithium difluorophosphate and 1,3-dioxolane,
A complex compound comprising lithium fluorosulfonate, lithium tetrafluoroborate and 1,3-dioxolan-2-one,
A complex compound consisting of lithium fluorosulfonate, lithium tetrafluoroborate and 4-fluoro-1,3-dioxolan-2-one, or
The lithium salt complex compound according to any one of claims 1 to 3, which is a complex compound comprising lithium fluorosulfonate, lithium tetrafluoroborate, and 1,3-dioxolane.   The additive for lithium secondary batteries containing the lithium salt complex compound of any one of Claims 1-4.