Compound and composition, use of those in batteries, method for using those in batteries, electrolyte solution, method for producing electrolyte solution, battery, method for producing battery, and vehicle

Abstract

The present invention relates to an anion-containing compound which has an S=O bond and an S-F bond and has a fluorosulfonic acid anion as a constituent component, the anion-containing compound being used in a battery that has a negative electrode which contains elemental niobium.

Description

Compounds and compositions, their use in batteries and methods for using them in batteries, electrolytes, methods for producing electrolytes, batteries, methods for producing batteries, and vehicles

[0001] The present invention relates to anion-containing compounds or compounds, compositions thereof, their use in batteries and methods for using them in batteries, electrolytes, methods for using electrolytes, batteries, methods for manufacturing batteries, and vehicles.

[0002] Lithium-ion rechargeable batteries, among others, are widely used in applications such as power supplies for small devices like mobile phones and laptops, and power supplies for vehicles like electric cars. Therefore, numerous studies have been conducted on various battery components, including the positive electrode, negative electrode, and electrolyte, as means of improving battery characteristics.

[0003] For example, Patent Document 1 discloses a lithium-ion secondary battery using a titanium-containing metal oxide as the negative electrode active material, in which a non-aqueous electrolyte containing 10 ppm or more of a specific compound is used to reduce output resistance and enable efficient energy utilization. Furthermore, Patent Document 2 discloses a working electrode having a niobium-containing metal oxide surface layer as a novel electrode material for lithium-ion batteries capable of operating at high rates and high temperatures.

[0004] Japanese Patent Publication No. 2007-214120 Japanese Special Publication No. 2022-552717

[0005] In recent years, there has been a demand for shorter charge-discharge times for secondary batteries, particularly in automotive applications, and the rate characteristics during rapid charge-discharge have become a challenge. Conventional lithium-ion secondary batteries using graphite as the negative electrode active material have a low negative electrode potential of 0.2V during charging, which causes lithium electrodeposition during rapid charge-discharge, making safe charging and discharging impossible. On the other hand, lithium-ion secondary batteries using lithium titanium composite oxide as the negative electrode active material have a negative electrode potential of 1V or more during charging, allowing for safe charging and discharging without lithium electrodeposition even during rapid charge-discharge. However, their capacity is significantly lower, posing a challenge in terms of capacity during rapid charge-discharge. In fact, the lithium-ion secondary battery disclosed in Patent Document 1 uses lithium titanium composite oxide as the negative electrode active material, so there is room for improvement in capacity during rapid charge. Furthermore, while lithium-ion secondary batteries using niobium as the negative electrode are expected to improve charging safety and capacity during rapid charge-discharge, the formation of a suitable film for rapid charge-discharge is insufficient, resulting in insufficient capacity during rapid charge. In fact, the lithium-ion secondary battery disclosed in Patent Document 2 has insufficient coating formation suitable for rapid charging, so improvement in capacity during rapid charging and discharging is desired.

[0006] This invention has been made in view of the above problems, and aims to provide a compound that can exhibit good effects when used in a battery having a negative electrode containing niobium, or a composition containing the above compound. One aspect of the above effect is the capacity during rapid charge and discharge. That is, one object of this invention is to provide a compound that exhibits excellent capacity during rapid charge and discharge when used in a battery having a negative electrode containing niobium, or a composition containing the above compound. Another object of this invention is to provide the use of the above compound or composition, which exhibits excellent capacity during rapid charge and discharge, in a battery having a negative electrode containing niobium, or a method for using the above compound or composition in a battery having a negative electrode containing niobium. Another object of this invention is to provide an electrolyte for a battery having a negative electrode containing niobium that exhibits excellent capacity during rapid charge and discharge. Another object of this invention is to provide a method for producing an electrolyte that exhibits excellent capacity during rapid charge and discharge when used in a battery having a negative electrode containing niobium. Another object of this invention is to provide a battery having a negative electrode containing niobium that exhibits excellent capacity during rapid charge and discharge. Furthermore, one of the objectives of the present invention is to provide a method for manufacturing a battery having a negative electrode containing niobium, which exhibits excellent capacity during rapid charging and discharging. Moreover, another objective of the present invention is to provide a vehicle comprising a battery having a negative electrode containing niobium, which exhibits excellent capacity during rapid charging and discharging.

[0007] As a result of diligent research to solve the above problems, the present inventors have found that, in a first aspect, applying a specific anion-containing compound having S=O bonds and S-F bonds, or a composition containing the above anion-containing compound, to a battery having a negative electrode containing niobium, produces effects such as superior capacity during rapid charging of the battery, thus completing the present invention. Furthermore, in a second aspect, they have found that applying a compound having Si-F bonds, or a composition containing the above compound, to a battery having a negative electrode containing niobium, produces effects such as superior capacity during rapid charging and discharging of the battery, thus completing the present invention. Moreover, in a third aspect, they have found that applying a compound having a specific structure, or a composition containing the above compound, to a battery having a negative electrode containing niobium, produces effects such as superior capacity during rapid charging of the battery, thus completing the present invention.

[0008] In other words, the gist of the present invention is as follows: [1] An anion-containing compound having an S=O bond and an S-F bond and comprising a fluorosulfonic acid anion as a component, for use in a battery having a negative electrode containing niobium. [2] A composition comprising the anion-containing compound described in [1]. [3] Use of the anion-containing compound described in [1] or the composition described in [2] in a battery having a negative electrode containing niobium. [4] A method for using the anion-containing compound described in [1] or the composition described in [2] in a battery having a negative electrode containing niobium. [5] An electrolyte comprising the anion-containing compound described in [1] or the composition described in [2], an electrolyte, and a non-aqueous solvent, for use in a battery having a negative electrode containing niobium. [6] The electrolyte according to [5], wherein the ratio (x / n) (mass% / unit) of the content x mass% of the anion-containing compound having S=O bonds and S-F bonds and comprising a fluorosulfonic acid anion as a component in the electrolyte to the number of S=O bonds n in one molecule of the anion-containing compound having S=O bonds and S-F bonds and comprising a fluorosulfonic acid anion as a component in the electrolyte is 3.0 or less. [7] A method for producing an electrolyte used in a battery having a negative electrode containing an element of niobium, comprising the step of dissolving the anion-containing compound according to [1] or the composition according to [2] and the electrolyte in a non-aqueous solvent. [8] A battery comprising a positive electrode, a negative electrode containing an element of niobium, and the electrolyte according to [5] or [6]. [9] A method for producing a battery comprising the step of housing the positive electrode and the negative electrode containing an element of niobium in an outer casing, and the step of injecting the electrolyte according to [5] or [6] into the outer casing.

[10] A vehicle comprising the battery according to [8].

[0009]

[11] A compound having an Si-F bond, which is used in a battery having a negative electrode containing an element niobium.

[12] The compound according to

[11] , wherein the compound having an Si-F bond is a compound represented by the following general formula (1).

[0010]

[0011] (In general formula (1), R １ ~R ３Each of these independently represents a fluorine atom, a hydrocarbon group which may be substituted with a halogen atom, or a hydrocarbon group which has a polar group.

[0012]

[13] A composition comprising the compound described in

[11] or

[12] above.

[14] Use of the compound described in

[11] or

[12] above, or the composition described in

[13] above, in a battery having a negative electrode containing niobium.

[15] A method for using the compound described in

[11] or

[12] above, or the composition described in

[13] above, in a battery having a negative electrode containing niobium.

[0013]

[16] A compound represented by the following general formula (3), which is used in a battery having a negative electrode containing an element of niobium.

[0014]

[0015] (In general formula (3), R represents a hydrocarbon group which may be substituted with a halogen atom, or a hydrocarbon group which has a polar group.)

[0016]

[17] A composition comprising the compound described in

[16] .

[18] Use of the compound described in

[16] or the composition described in

[17] in a battery having a negative electrode containing niobium.

[19] A method for using the compound described in

[16] or the composition described in

[17] in a battery having a negative electrode containing niobium.

[0017] The compounds and compositions containing the compounds according to this embodiment can exhibit good effects when used in batteries having a negative electrode containing niobium. Furthermore, the compounds and compositions containing the compounds according to this embodiment exhibit excellent capacity during rapid charge and discharge when used in batteries having a negative electrode containing niobium. Moreover, by using the compounds and compositions according to this embodiment in batteries having a negative electrode containing niobium, or by adopting the method used for such batteries, excellent capacity during rapid charge and discharge can be obtained. Furthermore, the manufacturing method for batteries according to this embodiment yields batteries with excellent capacity during rapid charge and discharge. In addition, the vehicles according to this embodiment contain batteries with excellent capacity during rapid charge and discharge.

[0018] The following describes in detail embodiments for carrying out the present invention, but the following description is merely one example of an embodiment of the present invention, and the present invention is not limited to these. Furthermore, the present invention can be modified and implemented as desired without departing from its essence. In this specification, "~" is used to mean that the numerical values ​​described before and after it are included as the lower limit and upper limit. In this specification, mass% and weight%, and parts by mass and parts by weight are synonymous.

[0019] [1A. Anion-containing compounds and compositions] The anion-containing compound according to the first embodiment of this embodiment is an anion-containing compound having an S=O bond and an S-F bond, and having a fluorosulfonate anion as a constituent component. The above anion-containing compound is used in a battery having a negative electrode containing niobium. The composition according to the first embodiment of this embodiment also contains an anion-containing compound having an S=O bond and an S-F bond, and the above anion-containing compound has a fluorosulfonate anion as a constituent component. The above composition is also used in a battery having a negative electrode containing niobium.

[0020] As a result, for example, the above-mentioned negative electrode or battery exhibits superior capacity during rapid charging. The reason for this is not clear, but it is thought to be as follows: In a negative electrode containing niobium, high-valence niobium elements are present on the surface of the negative electrode active material in the discharge state. It is thought that the S=O bond sites of anion-containing compounds having S=O and S-F bonds interact with the high-valence niobium elements, allowing them to be effectively concentrated on the surface of the negative electrode active material containing niobium. As a result, with each repeated charge and discharge, the negative electrode surface containing niobium reacts with the anion-containing compounds having S=O and S-F bonds, forming a film on the electrode active material derived from the anion-containing compounds having S=O and S-F bonds. This film has excellent Li conductivity, which is thought to contribute to superior capacity during rapid charging, and this effect is more pronounced when the anion-containing compound contains fluorosulfonic acid anions as a component.

[0021] [1A-1. Anionic Compound Containing S=O Bond and S-F Bond] The anionic compound containing S=O bond and S-F bond in the first aspect of the present embodiment is a compound containing an anion having an S=O bond and having an S-F bond, and is not particularly limited as long as it contains fluorosulfonic acid anion as a constituent component. Hereinafter, the anionic compound containing S=O bond and S-F bond and containing fluorosulfonic acid anion as a constituent component may be simply referred to as "anionic compound containing S=O bond and S-F bond". When a mixture of two or more of the above anionic compounds containing S=O bond and S-F bond is used, it corresponds to the composition according to the first aspect of the present embodiment. That is, the composition according to the first aspect of the present embodiment contains an anionic compound having S=O bond and S-F bond and containing fluorosulfonic acid anion as a constituent component, but may contain one anionic compound having S=O bond and S-F bond and other components, or may contain two or more anionic compounds having S=O bond and S-F bond. When the composition according to the first aspect of the present embodiment contains two or more anionic compounds having S=O bond and S-F bond, it may further contain other components.

[0022] The anionic compound containing S=O bond and S-F bond in the first aspect of the present embodiment contains fluorosulfonic acid anion as a constituent component from one or more viewpoints of low-temperature output characteristics, high-rate charge-discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics.

[0023] The anionic compound containing S=O bond and S-F bond in the first aspect of the present embodiment is preferably an alkali metal salt, more preferably a lithium salt, a sodium salt, or a potassium salt, from the viewpoint of enhancing solubility, and further preferably a lithium salt from the viewpoint of improving cycle characteristics.

[0024] When the anion-containing compound or composition according to the first aspect of this embodiment is used in a lithium-ion battery, the counter cation of the anion-containing compound having S═O bonds and S—F bonds is preferably a lithium cation. When the anion-containing compound or composition according to the first aspect of this embodiment is used in a sodium-ion battery, the counter cation of the anion-containing compound having S═O bonds and S—F bonds is preferably a sodium cation. When the anion-containing compound or composition according to the first aspect of this embodiment is used in a potassium-ion battery, the counter cation of the anion-containing compound having S═O bonds and S—F bonds is preferably a potassium cation.

[0025] When the anion-containing compound having S═O bonds and S—F bonds according to the first aspect of this embodiment is a lithium salt, for example, as a lithium sulfonate salt, FSO ３ Li, CF ３ SO ３ Li and the like can be mentioned. Among these, from the viewpoint of improving low-temperature output characteristics, high-rate charge-discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics, FSO ３ Li is particularly preferable.

[0026] When the anion-containing compound having S═O bonds and S—F bonds is a sodium salt, for example, as a sodium sulfonate salt, FSO ３ Na, CF ３ SO ３ Na and the like can be mentioned. Among these, from the viewpoint of improving low-temperature output characteristics, high-rate charge-discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics, FSO ３ Na is particularly preferable.

[0027] When the anion-containing compound having S═O bonds and S—F bonds is a potassium salt, for example, as a potassium sulfonate salt, FSO ３ K, CF ３ SO ３ K and the like can be mentioned. Among these, from the viewpoint of improving low-temperature output characteristics, high-rate charge-discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics, FSO ３ K is particularly preferable.

[0028] In this specification, the identification of anion-containing compounds having S=O and S-F bonds, and the content of such anion-containing compounds, are measured by nuclear magnetic resonance (NMR) analysis. If the identification of anion-containing compounds having S=O and S-F bonds, or the measurement of their content, is difficult with nuclear magnetic resonance (NMR) analysis alone, other analyses such as infrared spectroscopy (IR) analysis and gas chromatography-mass spectrometry may be used in combination.

[0029] Anion-containing compounds having S=O bonds and S-F bonds can be produced by known methods.

[0030] [1B. Compounds and Compositions] The compound according to the second embodiment of this embodiment is a compound having an Si-F bond and is used in a battery having a negative electrode containing niobium. The composition according to the second embodiment of this embodiment contains a compound having an Si-F bond and is used in a battery having a negative electrode containing niobium. As a result, for example, the negative electrode or battery has excellent capacity during rapid charging and discharging.

[0031] The reason for this is not clear, but it is thought to be as follows: The negative electrode containing niobium generates anionic active sites in the active material as it charges. In compounds with Si-F bonds, the silicon atom is cationic due to the difference in electronegativity between the fluorine atom and the silicon atom. The reaction between the anionic sites after charging and the cationic sites of the Si-F bonded compound forms a film on the electrode active material derived from the Si-F bonded compound.

[0032] [1B-1. Compounds Having Si-F Bonds] The compounds having Si-F bonds in the second aspect of this embodiment are not particularly limited as long as they have Si-F bonds in their molecules. Furthermore, when a mixture is made using two or more of the above-mentioned compounds having Si-F bonds, it falls under the composition according to the second aspect of this embodiment. That is, the composition according to the second aspect of this embodiment contains a compound having Si-F bonds, and may contain one compound having Si-F bonds and other components, or may contain two or more compounds having Si-F bonds. If the composition according to the second aspect of this embodiment contains two or more compounds having Si-F bonds, it may further contain other components. An example of a compound having Si-F bonds according to the second aspect of this embodiment is a compound represented by the following general formula (1).

[0033]

[0034] (In general formula (1), R １ ~R ３ Each of these independently represents a fluorine atom, a hydrocarbon group which may be substituted with a halogen atom, or a hydrocarbon group which has a polar group.

[0035] [R １ ] In general formula (1), R １ This represents a hydrocarbon group which may be substituted with a fluorine atom, a halogen atom, or a hydrocarbon group which has a polar group. Among these, hydrocarbon groups which may be substituted with a fluorine atom or a halogen atom are preferred, and hydrocarbon groups which may be substituted with a halogen atom are more preferred.

[0036] The above R １ If R is a hydrocarbon group which may be substituted with a halogen atom, １The hydrocarbon group which may be substituted with halogen atoms preferably has 1 to 10 carbon atoms. Specific examples of hydrocarbon groups which may be substituted with halogen atoms having 1 to 10 carbon atoms include alkyl groups, alkenyl groups, alkynyl groups, aryl groups, and halogenated hydrocarbon groups in which some or all of the hydrogen atoms of the hydrocarbon group are substituted with halogen atoms. Specific examples of halogen atoms that substitute for hydrogen atoms include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms, with fluorine atoms and chlorine atoms being preferred, and fluorine atoms being particularly preferred. The above-mentioned halogen atoms are preferred because they tend to suppress side reactions on the electrode active material surface of the compound represented by general formula (1).

[0037] The above R １ The hydrocarbon group having 1 to 10 carbon atoms may be substituted with a halogen atom. Specific examples of alkyl groups when the hydrocarbon group is an alkyl group include linear alkyl groups such as methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, and n-decyl groups; branched alkyl groups such as i-propyl, methylpropyl, t-butyl, methylbutyl, methylpentyl, methylhexyl, methylheptyl, methyloctyl, and methylnonyl groups; and cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, cyclohexylmethyl, cyclohexylethyl, methylcyclohexyl, dimethylcyclohexyl, ethylcyclohexyl, and methylcyclohexylmethyl groups. Among the alkyl groups mentioned above, linear alkyl groups or branched alkyl groups are preferred, and linear alkyl groups are more preferred. Furthermore, when the alkyl group is a hydrocarbon group having 1 to 10 carbon atoms, which may be substituted with a halogen atom, the number of carbon atoms in the alkyl group is more preferably 1 to 6, even more preferably 1 to 4, and the alkyl group is more preferably a methyl group or an ethyl group, with the methyl group being the most preferred. The alkyl groups mentioned above are preferred because they tend to have less steric hindrance to the compound represented by general formula (1) and can react favorably with the electrode active material surface.

[0038] The above R １ The hydrocarbon group is a C1-C10 hydrocarbon group which may be substituted with a halogen atom. When the hydrocarbon group is an alkenyl group, specific examples of alkenyl groups include C2-C10 alkenyl groups such as vinyl group, allyl group, isopropenyl group, methallyl group, 2-butenyl group, 3-methyl-2-butenyl group, 3-butenyl group, or 4-pentenyl group. Linear alkenyl groups are preferred as the alkenyl group. More preferably, C2-C6 alkenyl groups such as vinyl group, allyl group, methallyl group, or 2-butenyl group are preferred, even more preferably C2-C4 alkenyl groups such as vinyl group, allyl group, or methallyl group are preferred, particularly preferably vinyl group or allyl group, and most preferably vinyl group. The above-mentioned alkenyl groups are preferred because the compound represented by general formula (1) tends to concentrate on the surface of the electrode active material.

[0039] The above R １ The hydrocarbon group is a C1-C10 hydrocarbon group which may be substituted with a halogen atom, and if the hydrocarbon group is an alkynyl group, the alkynyl group is substantially a C2-C10 alkynyl group. Specific examples include C2-C10 alkynyl groups such as ethynyl, 2-propynyl, 2-butynyl, 3-butynyl, 4-pentynyl, or 5-hexynyl groups. Linear alkynyl groups are preferred as the alkynyl group. More preferably, C2-C6 alkynyl groups such as ethynyl, 2-propynyl, 2-butynyl, or 3-butynyl groups are preferred, even more preferably C2-C4 alkynyl groups such as 2-propynyl or 3-butynyl groups are preferred, and particularly preferably, C2-propynyl groups are preferred. The above-mentioned alkynyl groups are preferred because the compound represented by general formula (1) tends to concentrate on the electrode active material surface.

[0040] The above R １The hydrocarbon group is a C1-C10 hydrocarbon group which may be substituted with a halogen atom, and if the hydrocarbon group is an aryl group, the aryl group is substantially a C6-C10 aryl group. Specific examples include C6-C12 aryl groups such as a phenyl group, a tolyl group, or a mesityl group. Among these, a C6-C7 aryl group such as a phenyl group or a tolyl group is preferred, and a phenyl group is particularly preferred. The above-mentioned aryl group is preferred because the compound represented by general formula (1) tends to concentrate on the electrode active material surface.

[0041] The above R １ When the hydrocarbon group is a C1-C10 hydrocarbon group substituted with a halogen atom, a halogenated hydrocarbon group means a hydrocarbon group in which the hydrogen atoms are substituted with halogen atoms. Specific examples include hydrocarbon groups having C1-C10, such as alkyl groups, alkenyl groups, alkynyl groups, and aryl groups, in which some or all of the hydrogen atoms are substituted with halogen atoms. More specifically, examples include trifluoromethyl group, 2,2,2-trifluoroethyl group, 3-fluoropropyl group, 4-fluorobutyl group, 5-fluoropentyl group, 6-fluorohexyl group, 2-fluorophenyl group, and pentafluorophenyl group. Among these, C1-C4 halogenated alkyl groups such as trifluoromethyl group, 2,2,2-trifluoroethyl group, 3-fluoropropyl group, and 4-fluorobutyl group are preferred, and C1-C4 fluorinated alkyl groups are more preferred. Furthermore, C1 or C2 halogenated alkyl groups such as trifluoromethyl group and 2,2,2-trifluoroethyl group are more preferred, and C1 or C2 fluorinated alkyl groups are even more preferred. Among these, the trifluoromethyl group is even more preferred. This is because, as described above, the halogenated hydrocarbon group tends to suppress side reactions on the electrode active material surface of the compound represented by general formula (1), making it preferable.

[0042] The above R １Specific examples of hydrocarbon groups having polar groups include carbonate group (-OC(=O)O-), carboxylic acid ester group (-OC(=O)-), ether group (-O-), thioether group (-S-), sulfonyl oxide group (-S(=O)-), sulfonyl group (-S(=O)-) ２ -), sulfonic acid ester group (-O (S=O) ２ -), sulfite ester group (-O (S=O) ２ O-), sulfate ester group (-O (S=O) ２ Examples of hydrocarbon groups include those having an O-), a phosphine group (-P-), a phosphine oxide group (-P(=O)-), a phosphonic acid ester group (-P(=O)(OR')O-), a phosphate ester group (-OP(=O)(OR')O-), an amino group (-NR'-), an amide group (-N(R')C(=O)-), a urea group (-N(R')C(=O)N(R')-), a nitrile group (-CN), an isocyanate group (-NCO), a thioisocyanate group (-NCS), etc. However, R' in the above functional groups represents a hydrocarbon group which may be substituted with a hydrogen atom or a halogen atom having 1 to 10 carbon atoms. Specific examples and preferred examples of hydrocarbon groups having 1 to 10 carbon atoms which may be substituted with a halogen atom are given above. １ These are similar to the specific examples and preferred examples of C1-C10 hydrocarbon groups that may be substituted with halogen atoms.

[0043] The above R １ When is a hydrocarbon group having a polar group, from the viewpoint of suitably concentrating the compound having an Si-F bond on the electrode active material surface and suppressing side reactions of the compound having an Si-F bond on the electrode active material surface, the hydrocarbon group having a polar group is preferably a group represented by the following general formula (2).

[0044]

[0045] (In general formula (2), R ４ and R ５ Each of these independently represents a hydrocarbon group having 1 to 10 carbon atoms, which may be substituted with halogen atoms. X represents a divalent alkylene group having 1 to 10 carbon atoms, and Y １ ~Y ３Each of the following independently represents a single bond or an oxygen atom; Z represents a carbon atom, a sulfur atom, or a phosphorus atom; n represents an integer of 1 or 2; and m represents an integer of 0 or 1. However, when Z is a carbon atom, n is 1 and m is 0; when Z is a sulfur atom, n is 1 or 2 and m is 0; and when Z is a phosphorus atom, n is 1 and m is 1.

[0046] In the above general formula (2), R ４ and R ５ Each of these independently represents a hydrocarbon group having 1 to 10 carbon atoms, which may be substituted with a halogen atom. Specific and preferred examples are shown in the above R. １ These are similar to the specific examples and preferred examples of C1-C10 hydrocarbon groups that may be substituted with halogen atoms.

[0047] In the above general formula (2), specific examples of the divalent alkylene group having 1 to 10 carbon atoms, which is X, include methylene group, ethylene group, trimethylene group, tetramethylene group, pentamethylene group, hexamethylene group, heptamethylene group, octamethylene group, and the like. Among the above, linear alkylene groups or branched alkylene groups are preferred, and linear alkylene groups are more preferred. Furthermore, the number of carbon atoms in the alkylene group is preferably 1 to 6, more preferably 1 to 4, and particularly preferably 1 to 3. The above alkylene groups are preferred because the compound represented by general formula (1) tends to concentrate on the surface of the electrode active material.

[0048] In the general formula (2) above, Z represents a carbon atom, a sulfur atom, or a phosphorus atom. Among these, a carbon atom or a sulfur atom is preferred, and a carbon atom is particularly preferred. This is because the aforementioned atoms tend to suppress side reactions on the electrode active material surface of the compound represented by general formula (1), making them preferable.

[0049] When Z is a carbon atom, n is 1, m is 0, and Y １ and Y ３ Each of these independently represents a single bond or an oxygen atom. Among them, Y １ is a single bond or oxygen atom, Y ３ A preferred embodiment is one in which Y is an oxygen atom. １ This is an oxygen atom, Y３ A more preferable embodiment is one in which the atom is an oxygen atom. This is preferable because, in the above embodiment, side reactions on the electrode active material surface of the compound represented by general formula (1) tend to be suppressed.

[0050] When Z is a sulfur atom, n is 1 or 2, m is 0, and Y １ and Y ３ Each of these independently represents a single bond or an oxygen atom. n is preferably 2. １ is a single bond or oxygen atom, Y ３ A preferred embodiment is one in which Y is an oxygen atom. １ It is a single bond, Y ３ A more preferable embodiment is one in which the atom is an oxygen atom. This is preferable because, in the above embodiment, side reactions on the electrode active material surface of the compound represented by general formula (1) tend to be suppressed.

[0051] When Z is a phosphorus atom, n is 1 and m is 1. １ ~Y ３ Each of these independently represents a single bond or an oxygen atom. １ This is an oxygen atom, Y ２ This is an oxygen atom, Y ３ A form in which is a single bond or an oxygen atom is preferred, Y １ This is an oxygen atom, Y ２ This is an oxygen atom, Y ３ A configuration in which the bond is a single bond is more preferable. This configuration is preferable because it tends to suppress side reactions on the electrode active material surface of the compound represented by general formula (1).

[0052] The above R １ Among them, R is preferred because it exhibits low steric hindrance and tends to react favorably with the electrode active material surface. １A hydrocarbon group having 1 to 10 carbon atoms may be substituted with a fluorine atom or a halogen atom; a hydrocarbon group having 1 to 10 carbon atoms may be substituted with a halogen atom; a hydrocarbon group having 1 to 10 carbon atoms that is not substituted with a halogen atom is even more preferred; an alkyl group having 1 to 10 carbon atoms is even more preferred; an alkyl group having 1 to 3 carbon atoms is particularly preferred; a methyl group or an ethyl group is particularly preferred; and a methyl group is most preferred.

[0053] [R ２ ] In general formula (1), R ２ The symbol represents a hydrocarbon group which may be substituted with a fluorine atom, a halogen atom, or a hydrocarbon group which has a polar group. Among these, hydrocarbon groups which may be substituted with a halogen atom or a hydrocarbon group which has a polar group are preferred.

[0054] The above R ２ If R is a hydrocarbon group which may be substituted with a halogen atom, ２ Specific examples of hydrocarbon groups that may be substituted with halogen atoms include the above R １ The specific examples of C1-C10 hydrocarbon groups that may be substituted with halogen atoms are similar to those shown. Among these, halogen-unsubstituted C1-C10 hydrocarbon groups are preferred, C1-C10 alkyl groups are more preferred, and C4-C10 alkyl groups are particularly preferred. The above-mentioned groups are preferred because the volatility of the compound represented by general formula (1) is moderate, making electrolyte production, storage, and handling easier.

[0055] The above R ２ For specific and preferred examples of hydrocarbon groups having polar groups, see above R １ These are the same as the specific examples and preferred examples of hydrocarbon groups having polar groups shown.

[0056] The above R ２Among them, a hydrocarbon group optionally substituted with a halogen atom or a hydrocarbon group having a polar group is preferable, a hydrocarbon group having an alkyl group having 1 to 10 carbon atoms or a polar group represented by the general formula (2) is more preferable, and an alkyl group having 4 to 10 carbon atoms or a hydrocarbon group having a polar group represented by the general formula (2) in which Z is a carbon atom is particularly preferable. When it is the above group, the volatility of the compound represented by the general formula (1) is appropriate, and it is preferable because the production, storage, and handling of the electrolytic solution become easy.

[0057] [R ３ In the general formula (1), R ３ represents a fluorine atom, a hydrocarbon group optionally substituted with a halogen atom, or a hydrocarbon group having a polar group. Among them, a fluorine atom or a hydrocarbon group having 1 to 10 carbon atoms optionally substituted with a halogen atom is preferable.

[0058] When the above R ３ is a hydrocarbon group optionally substituted with a halogen atom, specific examples of the hydrocarbon group optionally substituted with a halogen atom of R ３ are the same as those shown as specific examples of the hydrocarbon group having 1 to 10 carbon atoms optionally substituted with a halogen atom of the above R １ . Among them, a halogen-free hydrocarbon group having 1 to 10 carbon atoms is preferable, an alkyl group or an alkenyl group having 1 to 10 carbon atoms is more preferable, an alkyl group having 1 to 10 carbon atoms is further preferable, an alkyl group having 1 to 3 carbon atoms is even more preferable, a methyl group or an ethyl group is particularly preferable, and a methyl group is most preferable. When it is the above group, the steric hindrance of the compound represented by the general formula (1) is small, and it tends to be able to react preferably with the surface of the electrode active material, so it is preferable.

[0059] Regarding specific examples and preferred examples of the hydrocarbon group having a polar group of the above R ３ , they are the same as those shown as specific examples and preferred examples of the hydrocarbon group having a polar group of the above R １ respectively.

[0060] Regarding the above R ３Among them, a hydrocarbon group having 1 to 10 carbon atoms which may be substituted with a fluorine atom or a halogen atom is preferable, a hydrocarbon group having 1 to 10 carbon atoms which is unsubstituted with a fluorine atom or a halogen atom is more preferable, a fluorine atom, an alkyl group having 1 to 10 carbon atoms, or an alkenyl group having 1 to 10 carbon atoms is further preferable, an alkyl group having 1 to 10 carbon atoms is even more preferable, an alkyl group having 1 to 3 carbon atoms is still more preferable, a methyl group or an ethyl group is particularly preferable, and a methyl group is most preferable. When it is the above-mentioned group, the steric hindrance of the compound represented by the general formula (1) is small, and it tends to be able to react suitably with the surface of the electrode active material, and thus it is preferable.

[0061] [R １ , R ２ , and R ３ [preferred combination] In the compound represented by the general formula (1) in the second aspect of the present embodiment, R １ is a hydrocarbon group which may be substituted with a halogen atom, R ３ is preferably a hydrocarbon group which may be substituted with a halogen atom or a fluorine atom, and R １ and R ３ are more preferably methyl groups. Further, R ２ being a hydrocarbon group having 4 or more carbon atoms which may be substituted with a halogen atom, or a hydrocarbon group having a polar group is also preferable. In the compound represented by the general formula (1) in the second aspect of the present embodiment, R １ is a hydrocarbon group which may be substituted with a halogen atom, R ２ is a hydrocarbon group having 4 or more carbon atoms which may be substituted with a halogen atom, or a hydrocarbon group having a polar group, R ３ is preferably a hydrocarbon group which may be substituted with a halogen atom or a fluorine atom, R １ and R ３ are methyl groups, and R ２ being a hydrocarbon group having 4 or more carbon atoms which may be substituted with a halogen atom, or a hydrocarbon group having a polar group is even more preferable.

[0062] Further, in the compound represented by the general formula (1) in the second aspect of the present embodiment, R １ is an alkyl group having 1 to 10 carbon atoms or a fluorine atom, R２ is a hydrocarbon group having an alkyl group or a polar group with 1 to 10 carbon atoms, and R ３ is preferably a fluorine atom, an alkyl group or an alkenyl group with 1 to 10 carbon atoms, and R １ is an alkyl group with 1 to 10 carbon atoms, and R ２ is a hydrocarbon group having an alkyl group or a polar group represented by the general formula (2) with 1 to 10 carbon atoms, and R ３ is more preferably a fluorine atom, an alkyl group or an alkenyl group with 1 to 10 carbon atoms, and R １ is an alkyl group with 1 to 10 carbon atoms, and R ２ is a hydrocarbon group having an alkyl group or a polar group represented by the general formula (2) with 1 to 10 carbon atoms, and R ３ is still more preferably an alkyl group with 1 to 10 carbon atoms, and R １ is an alkyl group with 1 to 3 carbon atoms, and R ２ is a group in which Z is a carbon atom among the hydrocarbon groups having an alkyl group with 4 to 10 carbon atoms or a polar group represented by the general formula (2), and R ３ is even more preferably an alkyl group with 1 to 3 carbon atoms, and R １ is a methyl group, and R ２ is a group in which Z is a carbon atom among the hydrocarbon groups having an alkyl group with 4 to 10 carbon atoms or a polar group represented by the general formula (2), and R ３ is particularly preferably a methyl group.

[0063] Specific examples of the compound represented by the general formula (1) are shown below. Note that the compound represented by the general formula (1) is not limited to the following examples.

[0064]

[0065]

[0066]

[0067]

[0068]

[0069]

[0070]

[0071]

[0072]

[0073]

[0074] Among those mentioned above, the compound represented by general formula (1) is R １ R is an alkyl group having 1 to 10 carbon atoms or a fluorine atom, ２ R is an alkyl group having 1 to 10 carbon atoms or a hydrocarbon group having a polar group, ３ Compounds in which are a fluorine atom, an alkyl group having 1 to 10 carbon atoms, or an alkenyl group are preferred, and specific examples of such compounds are those shown as (A-1) to (A-23), (B-1) to (B-18), (C-1) to (C-32), and (D-1) to (D-18). Also, R １ is an alkyl group having 1 to 10 carbon atoms, and R ２ R is an alkyl group having 1 to 10 carbon atoms or a hydrocarbon group having a polar group represented by general formula (2), ３ Compounds in which are a fluorine atom, an alkyl group having 1 to 10 carbon atoms, or an alkenyl group are more preferred, and as specific examples, the compounds shown in (A-1) to (A-23), (B-1) to (B-18), and (C-1) to (C-32) are more preferred. Also, R １ is an alkyl group having 1 to 10 carbon atoms, and R ２ R is an alkyl group having 1 to 10 carbon atoms or a hydrocarbon group having a polar group represented by general formula (2), ３ Compounds in which are alkyl groups having 1 to 10 carbon atoms are even more preferred, and as specific examples, the compounds shown in (A-1) to (A-23) and (B-1) to (B-18) are even more preferred. Also, R １ is an alkyl group having 1 to 3 carbon atoms, R ２ A is an alkyl group having 4 to 10 carbon atoms or a hydrocarbon group having a polar group represented by general formula (2), where Z is a carbon atom, and R ３ Compounds in which the group is an alkyl group having 1 to 3 carbon atoms are even more preferred, and as specific examples, (A-1) to (A-23) are even more preferred.

[0075] In this specification, the identification of compounds containing Si-F bonds and the content of compounds containing Si-F bonds are measured by nuclear magnetic resonance (NMR) analysis. If it is difficult to identify compounds containing Si-F bonds or measure the content of compounds containing Si-F bonds using nuclear magnetic resonance (NMR) analysis alone, other analyses such as infrared spectroscopy (IR) analysis and gas chromatography-mass spectrometry may be used in combination.

[0076] Compounds having an Si-F bond can be produced by known methods. Examples include fluorinating chlorosilane with hydrogen fluoride, hydrofluoric acid, metal fluoride, etc., and fluorinating alkoxysilane with hydrogen fluoride, hydrofluoric acid, metal fluoride, boron trifluoride, boron trifluoride complex, etc.

[0077] [1C. Compounds and Compositions] The compound according to the third aspect of this embodiment is a compound represented by the following general formula (3), and is used in a battery having a negative electrode containing niobium. The composition according to the third aspect of this embodiment contains a compound represented by the following general formula (3), and is used in a battery having a negative electrode containing niobium. As a result, for example, the negative electrode or battery has excellent capacity during rapid charging.

[0078]

[0079] (In general formula (3), R represents a hydrocarbon group which may be substituted with a halogen atom, or a hydrocarbon group which has a polar group.)

[0080] The reason for this is not clear, but it is thought to be as follows: In a negative electrode containing niobium, high-valence niobium elements are present on the surface of the negative electrode active material during the discharge state. It is thought that the S=O bond site of the compound represented by general formula (3) interacts with the high-valence niobium elements, allowing them to be effectively concentrated on the surface of the negative electrode active material containing niobium. As a result, with each charge and discharge cycle, the negative electrode surface containing niobium reacts with the compound represented by general formula (3), and a film derived from the compound represented by general formula (3) is formed on the electrode active material. Since this film has excellent Li conductivity, it is thought to have excellent capacity during rapid charging.

[0081] [1C-1. Compound represented by general formula (3)] The compound represented by general formula (3) in the third aspect of this embodiment is not particularly limited as long as it is a hydrocarbon group in which R in general formula (3) may be substituted with a halogen atom, or a hydrocarbon group having a polar group. Furthermore, when a mixture is used in combination of two or more compounds represented by general formula (3), it corresponds to the composition according to the third aspect of this embodiment. That is, the composition according to the third aspect of this embodiment contains a compound represented by general formula (3), and may contain one compound represented by general formula (3) and other components, or may contain two or more compounds represented by general formula (3). If the composition according to the third aspect of this embodiment contains two or more compounds represented by general formula (3), it may further contain other components.

[0082] The compound represented by general formula (3) according to the third aspect of this embodiment is a hydrocarbon group in which R in general formula (3) may be substituted with a halogen atom, or a hydrocarbon group having a polar group. From the viewpoint of having suitable reactivity on the negative electrode, a hydrocarbon group in which R may be substituted with a halogen atom is preferred.

[0083] If R is a hydrocarbon group which may be substituted with a halogen atom, the number of carbon atoms in the hydrocarbon group is preferably 1 to 10.

[0084] Specific examples of hydrocarbon groups that may be substituted with halogen atoms having 1 to 10 carbon atoms include alkyl groups, alkenyl groups, alkynyl groups, aryl groups, and halogenated hydrocarbon groups in which some or all of the hydrogen atoms of the hydrocarbon group are substituted with halogen atoms.

[0085] Specific examples of halogen atoms that can be substituted for hydrogen atoms include fluorine, chlorine, bromine, and iodine atoms, with fluorine and chlorine atoms being preferred, and fluorine atoms being particularly preferred. The above-mentioned halogen atoms are preferred because they tend to suppress side reactions on the electrode active material surface of the compound represented by general formula (3).

[0086] The above R is a C1 to C10 hydrocarbon group which may be substituted with a halogen atom. Specific examples of alkyl groups when the hydrocarbon group is an alkyl group include linear alkyl groups such as methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, and n-decyl groups; branched alkyl groups such as i-propyl, methylpropyl, t-butyl, methylbutyl, methylpentyl, methylhexyl, methylheptyl, methyloctyl, and methylnonyl groups; and cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, cyclohexylmethyl, cyclohexylethyl, methylcyclohexyl, dimethylcyclohexyl, ethylcyclohexyl, and methylcyclohexylmethyl groups. Among the alkyl groups mentioned above, linear alkyl groups or branched alkyl groups are preferred, and linear alkyl groups are more preferred. Furthermore, when the alkyl group is a hydrocarbon group having 1 to 10 carbon atoms, which may be substituted with a halogen atom, the number of carbon atoms in the alkyl group is more preferably 1 to 6, even more preferably 1 to 4, and the alkyl group is more preferably a methyl group or an ethyl group, with the methyl group being the most preferred. The alkyl groups mentioned above are preferred because they tend to have less steric hindrance to the compound represented by general formula (3) and can react favorably with the electrode active material surface.

[0087] The above R is a C1-C10 hydrocarbon group which may be substituted with a halogen atom, and when the hydrocarbon group is an alkenyl group, specific examples of alkenyl groups include C2-C10 alkenyl groups such as vinyl group, allyl group, isopropenyl group, methallyl group, 2-butenyl group, 3-methyl-2-butenyl group, 3-butenyl group, or 4-pentenyl group. Linear alkenyl groups are preferred as the above alkenyl group. More preferably, C2-C6 alkenyl groups such as vinyl group, allyl group, methallyl group, or 2-butenyl group are preferred, even more preferably C2-C4 alkenyl groups such as vinyl group, allyl group, or methallyl group are preferred, particularly preferably vinyl group or allyl group, and most preferably vinyl group. The above alkenyl groups are preferred because the compound represented by general formula (3) tends to concentrate on the surface of the electrode active material.

[0088] The above R is a C1-C10 hydrocarbon group which may be substituted with a halogen atom, and when the hydrocarbon group is an alkynyl group, the alkynyl group is substantially a C2-C10 alkynyl group. Specific examples include C2-C10 alkynyl groups such as ethynyl, 2-propynyl, 2-butynyl, 3-butynyl, 4-pentynyl, or 5-hexynyl groups. Linear alkynyl groups are preferred as the above alkynyl groups. More preferably, C2-C6 alkynyl groups such as ethynyl, 2-propynyl, 2-butynyl, or 3-butynyl groups are preferred, even more preferably C2-C4 alkynyl groups such as 2-propynyl or 3-butynyl groups are preferred, and particularly preferably C2-propynyl groups are preferred. The above alkynyl groups are preferred because the compound represented by general formula (3) tends to concentrate on the electrode active material surface.

[0089] The above R is a C1-C10 hydrocarbon group which may be substituted with a halogen atom, and when the hydrocarbon group is an aryl group, the aryl group is substantially a C6-C10 aryl group. Specific examples include C6-C12 aryl groups such as a phenyl group, a tolyl group, or a mesityl group. Among these, a C6-C7 aryl group such as a phenyl group or a tolyl group is preferred, and a phenyl group is particularly preferred. The above-mentioned aryl group is preferred because the compound represented by general formula (3) tends to concentrate on the electrode active material surface.

[0090] When R is a C1-C10 hydrocarbon group substituted with a halogen atom, a halogenated hydrocarbon group means a hydrocarbon group in which the hydrogen atoms are substituted with halogen atoms. Specific examples include C1-C10 hydrocarbon groups, such as alkyl groups, alkenyl groups, alkynyl groups, and aryl groups, in which some or all of the hydrogen atoms are substituted with halogen atoms. More specifically, examples include trifluoromethyl group, 2,2,2-trifluoroethyl group, 3-fluoropropyl group, 4-fluorobutyl group, 5-fluoropentyl group, 6-fluorohexyl group, 2-fluorophenyl group, and pentafluorophenyl group. Among these, C1-C4 halogenated alkyl groups such as trifluoromethyl group, 2,2,2-trifluoroethyl group, 3-fluoropropyl group, and 4-fluorobutyl group are preferred, and C1-C4 fluorinated alkyl groups are more preferred. Furthermore, C1 or C2 halogenated alkyl groups such as trifluoromethyl and 2,2,2-trifluoroethyl are more preferred, and C1 or C2 fluorinated alkyl groups are even more preferred. Among these, the trifluoromethyl group is even more preferred. The above-mentioned halogenated hydrocarbon groups are preferred because they tend to suppress side reactions on the electrode active material surface of the compound represented by general formula (3).

[0091] Specific examples of cases where R is a hydrocarbon group having a polar group include carbonate group (-OC(=O)O-), carboxylic acid ester group (-OC(=O)-), ether group (-O-), thioether group (-S-), sulfonyl oxide group (-S(=O)-), sulfonyl group (-S(=O)-)２ -), sulfonic acid ester group (-O (S=O) ２ -), sulfite ester group (-O (S=O) ２ O-), sulfate ester group (-O (S=O) ２ Examples of hydrocarbon groups include those having an O-), a phosphine group (-P-), a phosphine oxide group (-P(=O)-), a phosphonic acid ester group (-P(=O)(OR')O-), a phosphate ester group (-OP(=O)(OR')O-), an amino group (-NR'-), an amide group (-N(R')C(=O)-), a urea group (-N(R')C(=O)N(R')-), a nitrile group (-CN), an isocyanate group (-NCO), a thioisocyanate group (-NCS), etc. However, in the above functional groups, R' represents a hydrocarbon group which may be substituted with a hydrogen atom or a halogen atom having 1 to 10 carbon atoms. Specific examples and preferred examples of hydrocarbon groups having 1 to 10 carbon atoms which may be substituted with a halogen atom are the same as those shown above as specific examples and preferred examples of hydrocarbon groups having 1 to 10 carbon atoms which may be substituted with a halogen atom for R.

[0092] When R is a hydrocarbon group having a polar group, the compound represented by general formula (3) is preferably concentrated on the electrode active material surface, and side reactions of the compound represented by general formula (3) on the electrode active material surface are suppressed. From this viewpoint, the hydrocarbon group having a polar group is preferably the group represented by general formula (2) below.

[0093]

[0094] (In general formula (2), R ４ and R ５ Each of these independently represents a hydrocarbon group having 1 to 10 carbon atoms, which may be substituted with halogen atoms. X represents a divalent alkylene group having 1 to 10 carbon atoms, and Y １ ~Y ３ Each of the following independently represents a single bond or an oxygen atom; Z represents a carbon atom, a sulfur atom, or a phosphorus atom; n represents an integer of 1 or 2; and m represents an integer of 0 or 1. However, when Z is a carbon atom, n is 1 and m is 0; when Z is a sulfur atom, n is 1 or 2 and m is 0; and when Z is a phosphorus atom, n is 1 and m is 1.

[0095] In the above general formula (2), R ４ and R ５ Each of these independently represents a hydrocarbon group having 1 to 10 carbon atoms that may be substituted with a halogen atom. Specific examples and preferred examples are the same as those shown above for the specific examples and preferred examples of the hydrocarbon group having 1 to 10 carbon atoms that may be substituted with a halogen atom of R.

[0096] In the above general formula (2), specific examples of the divalent alkylene group having 1 to 10 carbon atoms, which is X, include methylene, ethylene, trimethylene, tetramethylene, pentamethylene, hexamethylene, heptamethylene, and octamethylene groups. Among the above, linear alkylene groups or branched alkylene groups are preferred, and linear alkylene groups are more preferred. Furthermore, the number of carbon atoms in the alkylene group is preferably 1 to 6, more preferably 1 to 4, and particularly preferably 1 to 3. The above alkylene groups are preferred because the compound represented by general formula (3) tends to concentrate on the surface of the electrode active material.

[0097] In the general formula (2) above, Z represents a carbon atom, a sulfur atom, or a phosphorus atom. Among these, a carbon atom or a sulfur atom is preferred, and a carbon atom is particularly preferred. This is because the aforementioned atoms tend to suppress side reactions on the electrode active material surface of the compound represented by general formula (3), making them preferable.

[0098] When Z is a carbon atom, n is 1, m is 0, and Y １ and Y ３ Each of these independently represents a single bond or an oxygen atom. Among them, Y １ is a single bond or oxygen atom, Y ３ A preferred embodiment is one in which Y is an oxygen atom. １ This is an oxygen atom, Y ３ A more preferable embodiment is one in which the atom is an oxygen atom. This is preferable because, in the above embodiment, side reactions on the electrode active material surface of the compound represented by general formula (3) tend to be suppressed.

[0099] When Z is a sulfur atom, n is 1 or 2, m is 0, and Y １ and Y ３Each of these independently represents a single bond or an oxygen atom. n is preferably 2. １ is a single bond or oxygen atom, Y ３ A preferred embodiment is one in which Y is an oxygen atom. １ It is a single bond, Y ３ A more preferable embodiment is one in which the atom is an oxygen atom. This is preferable because, in the above embodiment, side reactions on the electrode active material surface of the compound represented by general formula (3) tend to be suppressed.

[0100] When Z is a phosphorus atom, n is 1 and m is 1. １ ~Y ３ Each of these independently represents a single bond or an oxygen atom. １ This is an oxygen atom, Y ２ This is an oxygen atom, Y ３ A form in which is a single bond or an oxygen atom is preferred, Y １ This is an oxygen atom, Y ２ This is an oxygen atom, Y ３ A configuration in which the bond is a single bond is more preferable. This configuration is preferable because it tends to suppress side reactions on the electrode active material surface of the compound represented by general formula (3).

[0101] Among the R groups mentioned above, from the viewpoint of having low steric hindrance and a tendency to react favorably with the electrode active material surface, R is preferably a C1-C10 hydrocarbon group which may be substituted with a fluorine atom or a halogen atom, more preferably a C1-C10 hydrocarbon group which may be substituted with a halogen atom, even more preferably an unsubstituted C1-C10 hydrocarbon group which may be substituted with a halogen atom, even more preferably an alkyl group which may be C1-C10, especially preferably an alkyl group which may be C1-C3, particularly preferably a methyl group or an ethyl group which is most preferred, and most preferably a methyl group which is most preferred.

[0102] Preferred specific examples of compounds represented by general formula (3) include the following:

[0103]

[0104] In this specification, the identification of the compound represented by general formula (3) and the content of the compound represented by general formula (3) are measured by nuclear magnetic resonance (NMR) analysis. If it is difficult to identify the compound represented by general formula (3) or measure the content of the compound represented by general formula (3) using nuclear magnetic resonance (NMR) analysis alone, other analyses such as infrared spectroscopy (IR) analysis and gas chromatography-mass spectrometry may be used in combination.

[0105] Compounds represented by general formula (3) can be produced by known methods.

[0106] [1-2. Negative electrode containing niobium element] The negative electrode in this embodiment contains the element niobium (Nb). The negative electrode has a negative electrode active material on at least a part of the current collector surface that is capable of electrochemically intercalating and releasing metal ions, and it is preferable to include the element niobium as the negative electrode active material from the viewpoint of increasing the charge and discharge capacity during rapid charge and discharge. The negative electrode active material may further contain other metals or metal compounds.

[0107] In this embodiment, when the negative electrode active material contains niobium, examples include metal oxides containing niobium metal. Specifically, for example, examples include metal oxides represented by the following compositional formula (I'-1).

[0108]

[0109] (In the composition formula (I'-1), M represents at least one element selected from Ti, W, Fe, Al, Cr, Ga, P, V, and Mo, where 0 ≤ a ≤ 2.00, 0 < b ≤ 1.00, 0 ≤ c < 1.00, 1.50 ≤ d ≤ 3.50, and b + c = 1.)

[0110] Details about the negative electrode containing niobium will be described later.

[0111] [1-3. Use of Compounds and Compositions] The method of using the anion-containing compound / composition according to the first embodiment, the compound / composition according to the second embodiment, and the compound / composition according to the third embodiment of this embodiment involves using each of the above compounds / compositions in a battery having a negative electrode containing niobium.

[0112] The specific method of use is not particularly limited, but examples include using the above compound or a composition containing the above compound as a component of the electrolyte and applying it to a battery, or using the above compound or a composition containing the above compound as a component of the negative electrode and applying it to a battery. In particular, it is preferable to use the above compound or composition as a component of the electrolyte.

[0113] [2. Electrolyte] The electrolyte according to this embodiment includes each of the compounds or compositions described in [1A. Anion-containing compounds / compositions], [1B. Compounds / compositions], or [1C. Compounds / compositions] above, an electrolyte, and a non-aqueous solvent. That is, the electrolyte according to the first aspect of this embodiment includes an anion-containing compound having S=O bonds and S-F bonds and comprising a fluorosulfonic acid anion as a component, or a composition containing the above-mentioned S=O bonds and S-F bonds and comprising a fluorosulfonic acid anion as a component, an electrolyte, and a non-aqueous solvent. The above-mentioned electrolyte is used in a battery having a negative electrode containing niobium. The electrolyte according to the second aspect of this embodiment includes a compound having Si-F bonds, or a composition containing the above-mentioned compound having Si-F bonds, an electrolyte, and a non-aqueous solvent. The above-mentioned electrolyte is used in a battery having a negative electrode containing niobium. The electrolyte according to the third aspect of this embodiment comprises a compound represented by general formula (3), or a composition containing a compound represented by general formula (3), an electrolyte, and a non-aqueous solvent. The electrolyte is used in a battery having a negative electrode containing niobium.

[0114] The electrolyte according to this embodiment may be used as is as the electrolyte for a battery having a negative electrode containing niobium, or it may be used as an electrolyte after adjusting its concentration.

[0115] [2A-1. Anion-containing compounds having S=O and S-F bonds] The anion-containing compounds having S=O and S-F bonds contained in the electrolyte according to the first embodiment of this embodiment are described in the same way as the anion-containing compounds having S=O and S-F bonds described in [1A-1. Anion-containing compounds having S=O and S-F bonds] above, and the preferred embodiments are also the same. Furthermore, the anion-containing compounds having S=O and S-F bonds in the composition contained in the electrolyte according to the first embodiment of this embodiment are described in the same way as the anion-containing compounds having S=O and S-F bonds described in [1A-1. Anion-containing compounds having S=O and S-F bonds] above, and the preferred embodiments are also the same.

[0116] In the first embodiment of this model, the content of the anion-containing compound having S=O and S-F bonds in the electrolyte is preferably 0.00001% by mass or more and 20% by mass or less. Here, from the viewpoint of improving low-temperature characteristics, the above content is preferably 0.00001% by mass or more, more preferably 0.0001% by mass or more, even more preferably 0.001% by mass or more, even more preferably 0.01% by mass or more, especially preferably 0.05% by mass or more, particularly preferably 0.1% by mass or more, and most preferably 0.5% by mass or more. Furthermore, from the viewpoint of suppressing the increase in viscosity of the electrolyte, the above content is preferably 20% by mass or less, more preferably 15% by mass or less, even more preferably 10% by mass or less, even more preferably 5% by mass or less, especially preferably 3% by mass or less, and particularly preferably 2% by mass or less.

[0117] In the first embodiment of this invention, the ratio (x / n) (mass% / unit) of the content (x mass%) of an anion-containing compound having S=O bonds and S-F bonds in the electrolyte to the number of S=O bonds (n units) in one molecule of the anion-containing compound having S=O bonds and S-F bonds is preferably 5.0 or less, more preferably 3.25 or less, even more preferably 3.0 or less, and still more preferably 0.00001 to 3.0. Here, the above ratio (x / n) is preferably 5.0 or less, more preferably 3.25 or less, even more preferably 3.0 or less, still more preferably 2.5 or less, especially preferably 2.0 or less, still still preferably 1.5 or less, particularly preferably 1.0 or less, and most preferably 0.75 or less. Furthermore, the ratio of x / n is greater than 0, preferably 0.00001 or more, more preferably 0.0001 or more, even more preferably 0.001 or more, even more preferably 0.01 or more, particularly preferably 0.05 or more, and most preferably 0.1 or more. When x / n is within the above range, the S=O bond sites in the anion-containing compound having S=O and S-F bonds interact more favorably with the niobium-high-valence niobium element, and can be more effectively concentrated on the surface of the negative electrode active material containing the niobium element, which is therefore preferable.

[0118] When the electrolyte contains two or more anion-containing compounds having S=O bonds and S-F bonds, it is preferable that x / n is within the above range for at least one of the anion-containing compounds having S=O bonds and S-F bonds.

[0119] Methods for incorporating anion-containing compounds having S=O and S-F bonds into an electrolyte include adding the anion-containing compounds having S=O and S-F bonds to the electrolyte, as well as adding raw materials for anion-containing compounds having S=O and S-F bonds to the electrolyte to generate the anion-containing compounds having S=O and S-F bonds in the electrolyte.

[0120] [2B-1. Compounds Having Si-F Bonds] The same description as for the compounds having Si-F bonds described in [1B-1. Compounds Having Si-F Bonds] applies to the electrolyte solution contained in the second embodiment of this embodiment, and the preferred embodiment is also the same. Furthermore, the same description as for the compounds having Si-F bonds described in [1B-1. Compounds Having Si-F Bonds] applies to the compounds having Si-F bonds in the composition contained in the electrolyte solution according to the second embodiment of this embodiment, and the preferred embodiment is also the same.

[0121] In the second embodiment of this invention, the content of the compound having an Si-F bond in the electrolyte is preferably 0.0001% by mass or more and 20% by mass or less. Here, from the viewpoint of improving low-temperature characteristics, the above content is preferably 0.0001% by mass or more, more preferably 0.001% by mass or more, even more preferably 0.01% by mass or more, even more preferably 0.05% by mass or more, especially preferably 0.1% by mass or more, and particularly preferably 0.5% by mass or more. Furthermore, from the viewpoint of suppressing the increase in viscosity of the electrolyte, the above content is preferably 20% by mass or less, more preferably 15% by mass or less, even more preferably 10% by mass or less, even more preferably 5% by mass or less, and particularly preferably 3% by mass or less.

[0122] Methods for incorporating a compound having an Si-F bond into an electrolyte include adding the compound having an Si-F bond to the electrolyte, as well as adding a raw material for a compound having an Si-F bond to the electrolyte to generate the compound having an Si-F bond in the electrolyte.

[0123] [2C-1. Compound represented by general formula (3)] The compound represented by general formula (3) contained in the electrolyte according to the third aspect of this embodiment is described in the same way as the compound represented by general formula (3) described in [1C-1. Compound represented by general formula (3)] above, and the preferred embodiment is also the same. Furthermore, the compound represented by general formula (3) in the composition contained in the electrolyte according to the third aspect of this embodiment is described in the same way as the compound represented by general formula (3) described in [1C-1. Compound represented by general formula (3)] above, and the preferred embodiment is also the same.

[0124] In the third aspect of this embodiment, the content of the compound represented by general formula (3) in the electrolyte is preferably 0.0001% by mass or more and 20% by mass or less. Here, from the viewpoint of improving low-temperature characteristics, the above content is preferably 0.0001% by mass or more, more preferably 0.001% by mass or more, even more preferably 0.01% by mass or more, even more preferably 0.02% by mass or more, especially preferably 0.05% by mass or more, and particularly preferably 0.1% by mass or more. Furthermore, from the viewpoint of suppressing the increase in viscosity of the electrolyte, the above content is preferably 20% by mass or less, more preferably 15% by mass or less, even more preferably 10% by mass or less, even more preferably 5% by mass or less, and particularly preferably 3% by mass or less.

[0125] Methods for incorporating the compound represented by general formula (3) into the electrolyte include adding the compound represented by general formula (3) to the electrolyte, as well as adding the raw materials for the compound represented by general formula (3) to the electrolyte to generate the compound represented by general formula (3) in the electrolyte.

[0126] [2-2. Electrolyte] The electrolyte in this embodiment is not particularly limited as long as it can dissociate into cations and anions, even slightly, when dissolved in a non-aqueous solvent. However, anion-containing compounds having S=O bonds and S-F bonds according to the first embodiment of this embodiment are not included as electrolytes. From the viewpoint of increasing solubility, alkali metal salts are preferred for the electrolyte, lithium salts, sodium salts, and potassium salts are more preferred, and from the viewpoint of improving cycle characteristics, lithium salts are even more preferred. When the electrolyte according to this embodiment is used in a lithium-ion battery, the counter cation of the electrolyte is preferably a lithium cation. When the electrolyte according to this embodiment is used in a sodium-ion battery, the counter cation of the electrolyte is preferably a sodium cation. When the electrolyte according to this embodiment is used in a potassium-ion battery, the counter cation of the electrolyte is preferably a potassium cation.

[0127] Examples of lithium salts include lithium fluoroborate, lithium fluorophosphate, lithium sulfate, lithium tungstate, lithium carboxylate, lithium oxalate, and fluorine-containing organic lithium salts. A single lithium salt may be used, or two or more may be used in any ratio and combination.

[0128] Lithium salts are used as lithium fluoroborate salts (LiBF) from the viewpoint of improving low-temperature power characteristics, high-rate charge / discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics. ４ LiPF as lithium fluorophosphate salt ６ Li ２ PO ３ F, LiPO ２ F ２ ; as lithium sulfate, CH ３ SO ４ Li, CF ３ SO ４ Li, C ２ H ５ SO ４ Li, C ２ F ５ SO ４ Li, C ３ H ５ SO ４ Li, C ３ H ３ SO ４ Li; Lithium difluorooxalate borate, lithium bis(oxalate) borate, lithium tetrafluorooxalate phosphate, lithium difluorobis(oxalate) phosphate, and lithium tris(oxalate) phosphate are preferred as lithium oxalate salts. Among these, LiBF is preferred from the viewpoint of improving lower temperature power characteristics, high-rate charge / discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics. ４ LiPF ６ LiPO ２ F ２ Lithium bis(oxalate) borate is more preferred, and furthermore, LiPF is preferred from the viewpoint of improving low-temperature power characteristics, high-rate charge / discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics. ６ That is even more preferable.

[0129] Examples of combinations of two or more lithium salts include LiPF ６ and LiBF ４ Combinations such as the above are examples. Combinations of two or more lithium salts improve low-temperature power characteristics, high-rate charge / discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics, and LiPF ６ and LiBF ４ A combination is preferable.

[0130] Examples of sodium salts include sodium fluoroborate salts, sodium fluorophosphate salts, sodium sulfate salts, sodium tungstate salts, sodium carboxylate salts, sodium oxalate salts, and fluorine-containing organic sodium salts. Sodium salts may be used individually or in any ratio and combination of two or more types.

[0131] Sodium salts are used as sodium fluoroborate salts (NaBF) from the viewpoint of improving low-temperature power characteristics, high-rate charge / discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics. ４ ;NaPF as sodium fluorophosphate ６ Na ２ PO ３ F, NaPO ２ F ２ ; as sodium sulfate salt CH ３ SO ４ Na, CF ３ SO ４ Na, C ２ H ５ SO ４ Na, C ２ F ５ SO ４ Na, C ３ H ５ SO ４ Na, C ３ H ３ SO ４Na; Sodium difluorooxalate borate, sodium bis(oxalate) borate, sodium tetrafluorooxalate phosphate, sodium difluorobis(oxalate) phosphate, and sodium tris(oxalate) phosphate are preferred as sodium oxalate salts. Among these, NaBF is preferred from the viewpoint of improving lower temperature power characteristics, high-rate charge / discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics. ４ NaPF ６ NaPO ２ F ２ Sodium bis(oxalate) borate is more preferred, and furthermore, from the viewpoint of improving low-temperature power characteristics, high-rate charge / discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics, NaPF ６ That is even more preferable.

[0132] Examples of combinations of two or more sodium salts include NaPF ６ and NaBF ４ Combinations such as the following can be mentioned. Combinations of two or more sodium salts are considered to improve low-temperature power characteristics, high-rate charge / discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics, and NaPF ６ and NaBF ４ A combination is preferable.

[0133] Examples of potassium salts include potassium fluoroborate, potassium fluorophosphate, potassium sulfate, potassium tungstate, potassium carboxylate, potassium oxalate, and fluorine-containing organic potassium salts. Potassium salts may be used individually or in any ratio and combination of two or more types.

[0134] Potassium salts are used as potassium fluoroborate (KBF) from the viewpoint of improving low-temperature power characteristics, high-rate charge / discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics. ４ ; as potassium fluorophosphate KPF ６ _K ２ PO ３ F, KPO ２ F ２ ; as potassium sulfate salt CH３ SO ４ K, CF ３ SO ４ K, C ２ H ５ SO ４ K, C ２ F ５ SO ４ K, C ３ H ５ SO ４ K, C ３ H ３ SO ４ K; Potassium difluorooxalate borate, potassium bis(oxalate) borate, potassium tetrafluorooxalate phosphate, potassium difluorobis(oxalate) phosphate, and potassium tris(oxalate) phosphate are preferred as potassium oxalate salts. Among these, KBF is preferred from the viewpoint of improving lower temperature power characteristics, high-rate charge / discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics. ４ KPF ６ , KPO ２ F ２ Potassium bis(oxalate) borate is more preferred, and from the viewpoint of further improving low-temperature power characteristics, high-rate charge / discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics, KPF ６ That is even more preferable.

[0135] Examples of combinations of two or more potassium salts include KPF ６ and KBF ４ Combinations such as the following can be mentioned. Combinations of two or more potassium salts are considered to improve low-temperature power characteristics, high-rate charge / discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics, and KPF ６ and KBF ４ A combination is preferable.

[0136] The electrolyte content in the electrolyte solution according to this embodiment is preferably 5 to 20% by mass. Here, from the viewpoint of improving low-temperature power characteristics, high-rate charge-discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics, the above content is preferably 5% by mass or more, more preferably 7% by mass or more, and even more preferably 9% by mass or more. Furthermore, from the viewpoint of improving low-temperature power characteristics, high-rate charge-discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics, the above content is preferably 20% by mass or less, more preferably 18% by mass or less, and even more preferably 16% by mass or less. Here, if two or more types of electrolytes are included, the above content refers to the total content of those electrolytes. In this specification, the identification of electrolytes and the electrolyte content are measured by nuclear magnetic resonance (NMR) analysis. If it is difficult to identify electrolytes or measure the electrolyte content by nuclear magnetic resonance (NMR) analysis alone, other analyses such as infrared spectroscopy (IR) analysis and gas chromatography-mass spectrometry may be used in combination.

[0137] When using two or more electrolytes, it is preferable to combine a first electrolyte and a second electrolyte from the viewpoint of improving low-temperature power characteristics, high-rate charge / discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics.

[0138] The first electrolyte is preferably an electrolyte with a high degree of ion dissociation and primarily responsible for carrier transport between electrodes, such as LiBF. ４ LiPF ６ More preferably, LiPF ６ The second electrolyte is preferably one with a low degree of ion dissociation and which is mainly responsible for roles other than carrier transport between electrodes, such as film formation on the electrode active material, such as LiPO ２ F ２ Lithium bis(oxalate) borate, CH ３ SO ４ Li, C ２ H ５ SO ４ Li is more preferable, LiPO ２ F ２、 CH ３ SO ４ Li, C ２ H ５ SO ４ Li is particularly preferable.

[0139] The combination of the first and second electrolytes can be appropriately selected based on the degree of ionization and effects of the electrolytes, for example, LiPF ６ and LiPO ２ F ２ LiPF ６ and lithium bis(oxalate) borate, LiPF ６ and CH ３ SO ４ Li, LiPF ６ and C ２ H ５ SO ４ Li is one example. The combination of the first and second electrolytes is LiPFF, from the viewpoint of improving low-temperature power characteristics, high-rate charge / discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics. ６ and LiPO ２ F ２ LiPF ６ and CH ３ SO ４ Li, LiPF ６ and C ２ H ５ SO ４ Li is preferred.

[0140] The content of the first electrolyte in the electrolyte solution according to this embodiment is preferably 4 to 19% by mass. Here, from the viewpoint of improving low-temperature power characteristics, high-rate charge-discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics, the above content is preferably 4% by mass or more, more preferably 6% by mass or more, and even more preferably 8% by mass or more. Furthermore, from the viewpoint of improving low-temperature power characteristics, high-rate charge-discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics, the above content is preferably 19% by mass or less, more preferably 17% by mass or less, and even more preferably 15% by mass or less. Here, if two or more types of first electrolytes are included, the above content refers to the total content of those electrolytes.

[0141] The content of the second electrolyte in the electrolyte according to this embodiment is preferably 0.001 to 5% by mass. Here, from the viewpoint of improving the DC resistance maintenance rate after high-temperature storage and the gas generation suppression effect after high-temperature storage, the above content is preferably 0.001% by mass or more, more preferably 0.01% by mass or more, and even more preferably 0.1% by mass or more. Furthermore, from the viewpoint of improving the DC resistance maintenance rate after high-temperature storage and the gas generation suppression effect after high-temperature storage, the above content is preferably 5% by mass or less, more preferably 4% by mass or less, and even more preferably 3% by mass or less. Here, if two or more types of second electrolytes are included, the above content refers to the total content of those electrolytes.

[0142] The mass ratio of the first electrolyte to the second electrolyte (content of the second electrolyte (mass%) / content of the first electrolyte (mass%)) is preferably 0.0001 to 0.5. Here, from the viewpoint of improving the DC resistance maintenance rate after high-temperature storage and the effect of suppressing gas generation after high-temperature storage, the above mass ratio is preferably 0.0001 or higher, more preferably 0.001 or higher, and even more preferably 0.01 or higher. Furthermore, from the viewpoint of improving the DC resistance maintenance rate after high-temperature storage and the effect of suppressing gas generation after high-temperature storage, the above mass ratio is preferably 0.5 or lower, more preferably 0.4 or lower, and even more preferably 0.3 or lower. Note that the above ratio can be appropriately determined depending on the type of battery to which the electrolyte according to this embodiment is applied and the usage environment. Here, if the first electrolyte or the second electrolyte contains two or more compounds, the above content rates refer to the total content of those compounds.

[0143] Furthermore, it is also preferable to use an anion-containing compound having an S=O bond and an S-F bond and comprising a fluorosulfonylimide anion as a component, or an anion-containing compound having an S=O bond and an S-F bond and comprising a fluorosulfonylmethide anion as a component, as the electrolyte in this embodiment.

[0144] Anion-containing compounds having S=O bonds and S-F bonds, and comprising a fluorosulfonylimide anion or fluorosulfonylmethide anion as a component, are preferably alkali metal salts from the viewpoint of increasing solubility, more preferably lithium salts, sodium salts, or potassium salts, and even more preferably lithium salts from the viewpoint of improving cycle characteristics.

[0145] When the electrolyte according to this embodiment is used in a lithium-ion battery, the countercation of the anion-containing compound having an S=O bond and an S-F bond and comprising a fluorosulfonylimide anion or a fluorosulfonylmethide anion as a component is preferably a lithium cation. When the electrolyte according to this embodiment is used in a sodium-ion battery, the countercation of the anion-containing compound having an S=O bond and an S-F bond and comprising a fluorosulfonylimide anion or a fluorosulfonylmethide anion as a component is preferably a sodium cation. When the electrolyte according to this embodiment is used in a potassium-ion battery, the countercation of the anion-containing compound having an S=O bond and an S-F bond and comprising a fluorosulfonylimide anion or a fluorosulfonylmethide anion as a component is preferably a potassium cation.

[0146] Lithium salts of anion-containing compounds having the above-mentioned S=O bond and S-F bond and comprising a fluorosulfonylimide anion as a component include LiN(FSO ２ ) ２ , LiN (FSO ２ ) (F ２ PO), LiN(FSO ２ ) (CF ３ SO ２ ), LiN (CF ３ SO ２ ) ２ ,LiN(C ２ F ５ SO ２ ) ２ Examples include lithium cyclic 1,2-perfluoroethanedisulfonylimide and lithium cyclic 1,3-perfluoropropanedisulfonylimide. Lithium salts of anion-containing compounds having S=O bonds and S-F bonds and having fluorosulfonylmethide anions as constituent components include LiC(FSO ２ ) ３ LiC (CF ３ SO ２ ) ３ LiC(C ２ F ５ SO ２ ) ３These are some examples. In particular, from the viewpoint of improving low-temperature power characteristics, high-rate charge / discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics, LiN (FSO) ２ ) ２ , LiN (FSO ２ ) (F ２ PO) is preferred.

[0147] The sodium salt of the anion-containing compound having the above-mentioned S=O bond and S-F bond and comprising a fluorosulfonylimide anion as a component is NaN(FSO). ２ ) ２ NaN(FSO) ２ ) (F ２ PO), NaN(FSO ２ ) (CF ３ SO ２ ), NaN(CF ３ SO ２ ) ２ NaN(C) ２ F ５ SO ２ ) ２ Examples include sodium cyclic 1,2-perfluoroethanedisulfonylimide and sodium cyclic 1,3-perfluoropropanedisulfonylimide. Examples of sodium salts of anion-containing compounds having S=O bonds and S-F bonds and having fluorosulfonylmethide anions as constituent components include NaC(FSO). ２ ) ３ NaC(CF ３ SO ２ ) ３ NaC(C ２ F ５ SO ２ ) ３ These are some examples. In particular, from the viewpoint of improving low-temperature power characteristics, high-rate charge / discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics, NaN (FSO) ２ ) ２ NaN(FSO) ２ ) (F ２ PO) is preferred.

[0148] As for potassium salts of anion-containing compounds having the above-mentioned S=O bond and S-F bond and comprising a fluorosulfonylimide anion as a component, KN(FSO)２ ) ２ , KN (FSO ２ ) (F ２ PO), KN (FSO ２ ) (CF ３ SO ２ ), KN (CF ３ SO ２ ) ２ , KN (C ２ F ５ SO ２ ) ２ Examples include potassium cyclic 1,2-perfluoroethanedisulfonylimide and potassium cyclic 1,3-perfluoropropanedisulfonylimide. Potassium salts of anion-containing compounds having S=O and S-F bonds and having fluorosulfonylmethide anions as constituent components include KC(FSO). ２ ) ３ , KC (CF ３ SO ２ ) ３ , KC (C ２ F ５ SO ２ ) ３ These are some examples. In particular, from the viewpoint of improving low-temperature power characteristics, high-rate charge / discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics, KN ​​(FSO) ２ ) ２ , KN (FSO ２ ) (F ２ PO) is preferred.

[0149] In this specification, the identification and content of anion-containing compounds having S=O bonds and S-F bonds and comprising fluorosulfonylimide anions or fluorosulfonylmethide anions as constituent components shall be measured by nuclear magnetic resonance (NMR) analysis. If the above identification and content measurement are difficult with nuclear magnetic resonance (NMR) analysis alone, other analyses such as infrared spectroscopy (IR) analysis and gas chromatography-mass spectrometry may be used in combination.

[0150] Anion-containing compounds having an S=O bond and an S-F bond, and comprising a fluorosulfonylimide anion or a fluorosulfonylmethide anion as a component, can be produced by known methods.

[0151] [2-3. Non-aqueous solvents] The non-aqueous solvent in this embodiment is not particularly limited as long as it is a non-aqueous solvent that dissolves the electrolyte, as well as the anion-containing compound having an S=O bond and an S-F bond in the first embodiment or a composition containing the same, the compound having an Si-F bond in the second embodiment or a composition containing the same, or the compound represented by general formula (3) in the third embodiment or a composition containing the same. From the viewpoint of suppressing oxidation-reduction decomposition in the battery, organic solvents are preferred as the non-aqueous solvent.

[0152] Examples of organic solvents include saturated cyclic carbonates, linear carbonates, linear carboxylic acid esters, cyclic carboxylic acid esters, ether compounds, and sulfone compounds. One organic solvent may be used alone, or two or more may be used in any ratio and combination. From the viewpoint of suppressing oxidation-reduction decomposition in the battery, saturated cyclic carbonates, linear carbonates, linear carboxylic acid esters, cyclic carboxylic acid esters, ether compounds, and sulfone compounds are preferred organic solvents, and saturated cyclic carbonates, linear carbonates, and linear carboxylic acid esters are more preferred.

[0153] Examples of combinations of two or more organic solvents include a combination of saturated cyclic carbonate and linear carbonate, a combination of saturated cyclic carbonate and linear carboxylic acid ester, a combination of saturated cyclic carbonate and cyclic carboxylic acid ester, a combination of linear carbonate and linear carboxylic acid ester, and a combination of saturated cyclic carbonate, linear carbonate, and linear carboxylic acid ester. From the viewpoint of improving low-temperature power characteristics, high-rate charge / discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics, it is preferable that the combination of two or more organic solvents be a combination of saturated cyclic carbonate and linear carbonate, or a combination of saturated cyclic carbonate, linear carbonate, and linear carboxylic acid ester.

[0154] The content of the non-aqueous solvent in the electrolyte according to this embodiment is preferably 84 to 95% by mass. Here, from the viewpoint of improving low-temperature power characteristics, high-rate charge-discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics, the above content is preferably 84% by mass or more, more preferably 86% by mass or more, and even more preferably 88% by mass or more. Furthermore, from the viewpoint of improving low-temperature power characteristics, high-rate charge-discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics, the above content is preferably 95% by mass or less, more preferably 93% by mass or less, and even more preferably 91% by mass or less. Here, if two or more non-aqueous solvents are included, the above content refers to the total content of those solvents. In this specification, the identification of non-aqueous solvents and the content of non-aqueous solvents are measured by nuclear magnetic resonance (NMR) analysis. If it is difficult to identify non-aqueous solvents or measure the content of non-aqueous solvents by nuclear magnetic resonance (NMR) analysis alone, other analyses such as infrared spectroscopy (IR) analysis and gas chromatography-mass spectrometry may be used in combination.

[0155] [2-3-1. Saturated Cyclic Carbonates] Examples of saturated cyclic carbonates that serve as non-aqueous solvents in this embodiment include ethylene carbonate, propylene carbonate, butylene carbonate, and erythritol bis(carbonate). One type of saturated cyclic carbonate may be used alone, or two or more types may be used in any ratio and combination. From the viewpoint of improving the degree of alkali metal ion dissociation, ethylene carbonate and propylene carbonate are preferred, and ethylene carbonate is more preferred.

[0156] When saturated cyclic carbonate is used as the non-aqueous solvent, the content of saturated cyclic carbonate relative to the total non-aqueous solvent is preferably 3 to 90 volume percent. Here, from the viewpoint of suppressing the decrease in electrical conductivity due to the decrease in dielectric constant of the electrolyte and improving high-current discharge characteristics, stability to the negative electrode, cycle characteristics, oxidation-reduction resistance of the electrolyte, and high-temperature storage characteristics, the above content is preferably 3 volume percent or more, more preferably 5 volume percent or more, and even more preferably 10 volume percent or more. Furthermore, from the viewpoint of suppressing the decrease in electrical conductivity due to the decrease in dielectric constant of the electrolyte and improving high-current discharge characteristics, stability to the negative electrode, cycle characteristics, oxidation-reduction resistance of the electrolyte, and high-temperature storage characteristics, the above content is preferably 90 volume percent or less, more preferably 85 volume percent or less, and even more preferably 80 volume percent or less. Here, if two or more saturated cyclic carbonates are included, the above content refers to the total content of those two or more. In this specification, volume percent refers to the ratio of volume at 25°C and 1 atm.

[0157] [2-3-2. Chain-like carbonates] Examples of chain-like carbonates that serve as non-aqueous solvents in this embodiment include dimethyl carbonate, diethyl carbonate, di-n-propyl carbonate, diisopropyl carbonate, n-propylisopropyl carbonate, ethyl methyl carbonate, methyl-n-propyl carbonate, methylphenyl carbonate, and methyl-2,2,2-trifluoroethyl carbonate. One type of chain-like carbonate may be used alone, or two or more types may be used in any ratio and combination. From the viewpoint of suppressing an increase in the viscosity of the electrolyte, chain-like carbonates having 3 to 5 carbon atoms are preferred, and dimethyl carbonate, diethyl carbonate, and ethyl methyl carbonate are more preferred.

[0158] When a linear carbonate is used as the non-aqueous solvent, the content of the linear carbonate relative to the total non-aqueous solvent is preferably 15 to 90 volume percent. Here, from the viewpoint of ensuring that the viscosity of the electrolyte is within an appropriate range, that the decrease in ionic conductivity is suppressed, and that the output characteristics of the battery are within a good range, the above content is preferably 15 volume percent or more, more preferably 20 volume percent or more, and even more preferably 25 volume percent or more. Furthermore, from the viewpoint of ensuring that the viscosity of the electrolyte is within an appropriate range, that the decrease in ionic conductivity is suppressed, and that the output characteristics of the battery are within a good range, the above content is preferably 90 volume percent or less, more preferably 85 volume percent or less, and even more preferably 80 volume percent or less. Here, if two or more types of linear carbonates are included, the above content refers to the total content of those types.

[0159] In this embodiment, the non-aqueous solvent is preferably a combination of ethylene carbonate and a chain carbonate, and more preferably a combination of ethylene carbonate, dimethyl carbonate, and ethyl methyl carbonate, from the viewpoint of suppressing the increase in viscosity of the electrolyte and improving electrical conductivity.

[0160] When ethylene carbonate, dimethyl carbonate, and ethyl methyl carbonate are used as non-aqueous solvents, the content of ethylene carbonate relative to the total non-aqueous solvent is preferably 15 to 45 volume percent. Here, from the viewpoint of improving the rate characteristics due to improved ion dissociation, the above content is preferably 15 volume percent or more, more preferably 20 volume percent or more, and even more preferably 30 volume percent or more. Furthermore, from the viewpoint of improving the rate characteristics due to improved ion dissociation, the above content is preferably 45 volume percent or less, and more preferably 40 volume percent or less.

[0161] When ethylene carbonate, dimethyl carbonate, and ethyl methyl carbonate are used as non-aqueous solvents, the content of dimethyl carbonate relative to the total non-aqueous solvent is preferably 20 to 50% by volume. From the viewpoint of suppressing an increase in the viscosity of the electrolyte, the above content is preferably 20% by volume or more, and more preferably 30% by volume or more. From the viewpoint of improving the low-temperature characteristics of the battery, the above content is preferably 50% by volume or less, and even more preferably 45% by volume or less.

[0162] When ethylene carbonate, dimethyl carbonate, and ethyl methyl carbonate are used as non-aqueous solvents, the content of ethyl methyl carbonate relative to the total non-aqueous solvent is preferably 20 to 50 volume percent. Here, from the viewpoint of ensuring that the viscosity of the electrolyte is within an appropriate range, that the decrease in ionic conductivity is suppressed, and that the output characteristics of the battery are within a good range, the above content is preferably 20 volume percent or more, and more preferably 30 volume percent or more. Furthermore, from the viewpoint of ensuring that the viscosity of the electrolyte is within an appropriate range, that the decrease in ionic conductivity is suppressed, and that the output characteristics of the battery are within a good range, the above content is preferably 50 volume percent or less, and even more preferably 45 volume percent or less.

[0163] [2-3-3. Chain-like Carboxylic Acid Esters] Examples of chain-like carboxylic acid esters that serve as non-aqueous solvents in this embodiment include methyl acetate, ethyl acetate, propyl acetate, butyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, methyl valerate, methyl isobutyrate, ethyl isobutyrate, and methyl pivalate. One type of chain-like carboxylic acid ester may be used alone, or two or more types may be used in any ratio and combination. From the viewpoint of ensuring that the viscosity of the electrolyte is within an appropriate range, that the decrease in ionic conductivity is suppressed, and that the output characteristics of the battery are within a good range, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, and propyl propionate are preferred, and methyl acetate, ethyl acetate, and methyl propionate are more preferred.

[0164] The above-mentioned linear carboxylic acid ester may be a linear carboxylic acid ester in which some of the hydrogen atoms are replaced with fluorine atoms. Examples of fluorine-substituted linear carboxylic acid esters include methyl trifluoroacetate, ethyl trifluoroacetate, 2,2-difluoroethyl acetate, and 2,2,2-trifluoroethyl acetate. One type of fluorine-substituted linear carboxylic acid ester may be used alone, or two or more types may be used in any ratio and combination. From the viewpoint of suppressing the increase in viscosity of the electrolyte, methyl trifluoroacetate and ethyl trifluoroacetate are preferred as the fluorine-substituted linear carboxylic acid ester, and methyl trifluoroacetate is more preferred.

[0165] When a linear carboxylic acid ester is used as the non-aqueous solvent, the content of the linear carboxylic acid ester relative to the total non-aqueous solvent is preferably 1 to 70% by volume. Here, from the viewpoint of improving the electrical conductivity of the electrolyte and enhancing the high-current discharge characteristics of the battery, the above content is preferably 1% by volume or more, more preferably 5% by volume or more, and even more preferably 15% by volume or more. Furthermore, from the viewpoint of ensuring that the viscosity of the electrolyte is within an appropriate range, suppressing the decrease in electrical conductivity, suppressing the increase in negative electrode resistance, and ensuring that the high-current discharge characteristics of the battery are within a good range, the above content is preferably 70% by volume or less, more preferably 50% by volume or less, and even more preferably 40% by volume or less. Here, if two or more linear carboxylic acid esters are included, the above content refers to the total content of those esters.

[0166] [2-3-4. Cyclic Carboxylic Acid Esters] Examples of cyclic carboxylic acid esters that serve as non-aqueous solvents in this embodiment include γ-butyrolactone and γ-valerolactone. One type of cyclic carboxylic acid ester may be used alone, or two or more types may be used in any ratio and combination. From the viewpoint of improving electrical conductivity, γ-butyrolactone is preferred as the cyclic carboxylic acid ester.

[0167] The above-mentioned cyclic carboxylic acid ester may be a cyclic carboxylic acid ester in which some of the hydrogen atoms are replaced with fluorine atoms. Examples of fluorine-substituted cyclic carboxylic acid esters include 3-fluorotetrahydrofuran-2-one and 4-fluorotetrahydrofuran-2-one. A single fluorine-substituted cyclic carboxylic acid ester may be used, or two or more may be used in any ratio and combination. From the viewpoint of improving oxidation resistance, 3-fluorotetrahydrofuran-2-one is preferred as the fluorine-substituted cyclic carboxylic acid ester.

[0168] When a cyclic carboxylic acid ester is used as a non-aqueous solvent, the content of the cyclic carboxylic acid ester relative to the total non-aqueous solvent is preferably 1 to 70% by volume. Here, from the viewpoint of improving the electrical conductivity of the electrolyte and enhancing the high-current discharge characteristics of the battery, the above content is preferably 1% by volume or more, more preferably 5% by volume or more, and even more preferably 15% by volume or more. Furthermore, from the viewpoint of ensuring that the viscosity of the electrolyte is within an appropriate range, suppressing the decrease in electrical conductivity, suppressing the increase in negative electrode resistance, and ensuring that the high-current discharge characteristics of the battery are within a good range, the above content is preferably 70% by volume or less, more preferably 50% by volume or less, and even more preferably 40% by volume or less. Here, if two or more cyclic carboxylic acid esters are included, the above content refers to the total content of those esters.

[0169] [2-3-5. Ether Compounds] Examples of ether compounds that serve as non-aqueous solvents in this embodiment include chain ethers having 3 to 10 carbon atoms such as dimethoxymethane, diethoxymethane, ethoxymethoxymethane, ethylene glycol di-n-propyl ether, ethylene glycol di-n-butyl ether, and diethylene glycol dimethyl ether; and cyclic ethers having 3 to 6 carbon atoms such as tetrahydrofuran, 2-methyltetrahydrofuran, 3-methyltetrahydrofuran, 1,3-dioxane, 2-methyl-1,3-dioxane, 4-methyl-1,3-dioxane, and 1,4-dioxane. The ether compound may be an ether compound in which some of the hydrogen atoms are substituted with fluorine atoms. The ether compound may be used alone, or two or more may be used in any ratio and combination.

[0170] From the viewpoint of suppressing the increase in viscosity of the electrolyte, the above ether compounds are preferably chain ethers having 3 to 10 carbon atoms and cyclic ethers having 3 to 6 carbon atoms. Of the chain ethers having 3 to 10 carbon atoms, dimethoxymethane, diethoxymethane, and ethoxymethoxymethane are preferred from the viewpoint of having high solvation ability to lithium ions, improving ion dissociation, suppressing the increase in viscosity of the electrolyte, and improving ionic conductivity. Of the cyclic ethers having 3 to 6 carbon atoms, tetrahydrofuran, 1,3-dioxane, and 1,4-dioxane are preferred from the viewpoint of improving ionic conductivity.

[0171] When an ether compound is used as a non-aqueous solvent, the content of the ether compound relative to the total non-aqueous solvent is preferably 1 to 30 volume percent. Here, from the viewpoint of ensuring that the viscosity of the electrolyte is within an appropriate range, that the decrease in ionic conductivity is suppressed, and that the output characteristics of the battery are within a good range, the above content is preferably 1 volume percent or more, more preferably 2 volume percent or more, and even more preferably 3 volume percent or more. Furthermore, from the viewpoint of ensuring that the viscosity of the electrolyte is within an appropriate range, that the decrease in ionic conductivity is suppressed, and that the output characteristics of the battery are within a good range, the above content is preferably 30 volume percent or less, more preferably 25 volume percent or less, and even more preferably 20 volume percent or less. Here, if two or more ether compounds are included, the above content refers to the total content of those compounds.

[0172] [2-3-6. Sulfone Compounds] The sulfone compound that serves as the non-aqueous solvent in this embodiment may be a cyclic sulfone or a chain sulfone. One sulfone compound may be used alone, or two or more may be used in any ratio and combination. From the viewpoint of improving ionic conductivity, the number of sulfonyl groups in the sulfone compound is preferably 1 to 2, and more preferably 1.

[0173] Examples of the above-mentioned cyclic sulfones include monosulfone compounds such as trimethylene sulfones, tetramethylene sulfones (sulfolanes), and hexamethylene sulfones; and disulfone compounds such as trimethylene disulfones, tetramethylene disulfones, and hexamethylene disulfones. A single cyclic sulfone may be used, or two or more may be used in any ratio and combination. From the viewpoint of suppressing the increase in viscosity of the electrolyte, cyclic sulfones having 3 to 6 carbon atoms are preferred, chain-like sulfones having 3 to 5 carbon atoms are more preferred, and sulfolanes are even more preferred.

[0174] Examples of sulfolanes include sulfolane; sulfolane derivatives such as 2-methylsulfolane, 3-methylsulfolane, 2-fluorosulfolane, 3-fluorosulfolane, 2,3-difluorosulfolane, 2-trifluoromethylsulfolane, and 3-trifluoromethylsulfolane. Sulfolanes may be used individually or in any ratio and combination of two or more. From the viewpoint of improving ionic conductivity, sulfolane and sulfolane derivatives are preferred, and sulfolane, 2-methylsulfolane, 3-methylsulfolane, 2-fluorosulfolane, 3-fluorosulfolane, 2,3-difluorosulfolane, 2-trifluoromethylsulfolane, and 3-trifluoromethylsulfolane are more preferred.

[0175] From the viewpoint of improving oxidation resistance, sulfolane derivatives are preferably sulfolane derivatives in which one or more hydrogen atoms bonded to carbon atoms constituting the sulfolane ring are substituted with fluorine atoms, sulfolane derivatives in which one or more hydrogen atoms bonded to carbon atoms constituting the sulfolane ring are substituted with alkyl groups, and sulfolane derivatives in which one or more hydrogen atoms bonded to carbon atoms constituting the sulfolane ring are substituted with fluorine-substituted alkyl groups. More preferably are 2-methylsulfolane, 3-methylsulfolane, 2-fluorosulfolane, 3-fluorosulfolane, 2,3-difluorosulfolane, 2-trifluoromethylsulfolane, and 3-trifluoromethylsulfolane.

[0176] Examples of the above-mentioned chain-like sulfones include dimethyl sulfone, ethyl methyl sulfone, diethyl sulfone, monofluoromethyl methyl sulfone, difluoromethyl methyl sulfone, trifluoromethyl methyl sulfone, and pentafluoroethyl methyl sulfone. One type of chain-like sulfone may be used alone, or two or more types may be used in any ratio and combination. From the viewpoint of improving the high-temperature storage stability of the electrolyte, chain-like sulfones having 2 to 6 carbon atoms are preferred, chain-like sulfones having 2 to 5 carbon atoms are more preferred, and dimethyl sulfone, ethyl methyl sulfone, and monofluoromethyl methyl sulfone are even more preferred.

[0177] When a sulfone compound is used as a non-aqueous solvent, the content of the sulfone compound relative to the total non-aqueous solvent is preferably 0.3 to 40 volume percent. Here, from the viewpoint of ensuring that the viscosity of the electrolyte is within an appropriate range, that the decrease in ionic conductivity is suppressed, and that the output characteristics of the battery are within a good range, the above content is preferably 0.3 volume percent or more, more preferably 0.5 volume percent or more, and even more preferably 1 volume percent. Furthermore, from the viewpoint of ensuring that the viscosity of the electrolyte is within an appropriate range, that the decrease in ionic conductivity is suppressed, and that the output characteristics of the battery are within a good range, the above content is preferably 40 volume percent or less, more preferably 35 volume percent or less, and even more preferably 30 volume percent or less. Here, if two or more sulfone compounds are included, the above content refers to the total content of those compounds.

[0178] [2-4. Other Compounds] The electrolyte according to the first aspect of this embodiment may contain other compounds besides the anion-containing compound having an S=O bond and an S-F bond, or a composition containing the anion-containing compound having an S=O bond and an S-F bond, the electrolyte, and the non-aqueous solvent, to the extent that it does not significantly impair the effects of the present invention. The electrolyte according to the second aspect of this embodiment may contain other compounds besides the compound having an Si-F bond, or a composition containing the compound having an Si-F bond, the electrolyte, and the non-aqueous solvent, to the extent that it does not significantly impair the effects of the present invention. The electrolyte according to the third aspect of this embodiment may contain other compounds besides the compound represented by general formula (3), or a composition containing the compound represented by general formula (3), the electrolyte, and the non-aqueous solvent, to the extent that it does not significantly impair the effects of the present invention.

[0179] Other compounds include, for example, unsaturated cyclic carbonates, fluorine-containing cyclic carbonates, isocyanate group-containing organic compounds, isocyanuric acid skeleton-containing organic compounds, sulfur-containing organic compounds, phosphorus-containing organic compounds, silicon-containing compounds, aromatic compounds, cyano group-containing organic compounds, acid anhydride compounds, triple bond-containing compounds, and the like. Furthermore, the electrolyte according to the first aspect of this embodiment may contain, as other compounds, compounds having Si-F bonds in the second aspect or compounds represented by general formula (3) in the third aspect. The electrolyte according to the second aspect of this embodiment may contain, as other compounds, anion-containing compounds having S=O bonds and S-F bonds in the first aspect or compounds represented by general formula (3) in the third aspect. The electrolyte according to the third aspect of this embodiment may contain, as other compounds, anion-containing compounds having S=O bonds and S-F bonds in the first aspect or compounds having Si-F bonds in the second aspect. The other compounds may be used individually or two or more in any ratio and combination.

[0180] Other compounds that improve low-temperature power characteristics, high-rate charge / discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics are preferably unsaturated cyclic carbonates, fluorine-containing cyclic carbonates, isocyanate group-containing organic compounds, isocyanuric acid skeleton-containing organic compounds, sulfur-containing organic compounds, phosphorus-containing organic compounds, silicon-containing compounds, aromatic compounds, cyano group-containing organic compounds, acid anhydride compounds, and triple bond-containing compounds. Unsaturated cyclic carbonates, fluorine-containing cyclic carbonates, isocyanate group-containing organic compounds, and isocyanuric acid skeleton-containing organic compounds are more preferred, and unsaturated cyclic carbonates and fluorine-containing cyclic carbonates are even more preferred.

[0181] The total content of other compounds in the electrolyte according to this embodiment is preferably 0.1 to 20% by mass. Here, from the viewpoint of improving low-temperature power characteristics, high-rate charge-discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics, the total content is preferably 0.1% by mass or more, more preferably 0.2% by mass or more, and even more preferably 0.5% by mass or more. Furthermore, from the viewpoint of improving low-temperature power characteristics, high-rate charge-discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics, the content is preferably 20% by mass or less, more preferably 15% by mass or less, and even more preferably 10% by mass or less. In this specification, the identification of other compounds and the content of other compounds are measured by nuclear magnetic resonance (NMR) analysis. If it is difficult to identify other compounds or measure the content of other compounds by nuclear magnetic resonance (NMR) analysis alone, other analyses such as infrared spectroscopy (IR) analysis and gas chromatography-mass spectrometry may be used in combination.

[0182] [2-4-1. Unsaturated Cyclic Carbonates] Examples of unsaturated cyclic carbonates that can be used as other compounds in this embodiment include vinylene carbonates; ethylene carbonates substituted with substituents having aromatic rings, carbon-carbon double bonds, or carbon-carbon triple bonds; phenyl carbonates; vinyl carbonates; allyl carbonates; catechol carbonates, etc. Unsaturated cyclic carbonates may be used individually or two or more in any ratio and combination. From the viewpoint of improving low-temperature power characteristics, high-rate charge-discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics, vinylene carbonates and ethylene carbonates substituted with substituents having aromatic rings, carbon-carbon double bonds, or carbon-carbon triple bonds are preferred, and vinylene carbonates are more preferred.

[0183] Examples of vinylene carbonates include vinylene carbonate, methyl vinylene carbonate, 4,5-dimethyl vinylene carbonate, phenyl vinylene carbonate, 4,5-diphenyl vinylene carbonate, vinyl vinylene carbonate, 4,5-vinyl vinylene carbonate, allyl vinylene carbonate, and 4,5-diallyl vinylene carbonate. Vinylene carbonates may be used individually or in any ratio and combination of two or more types.

[0184] Examples of ethylene carbonates substituted with substituents having aromatic rings, carbon-carbon double bonds, or carbon-carbon triple bonds include vinylethylene carbonate, 4,5-divinylethylene carbonate, 4-methyl-5-vinylethylene carbonate, 4-allyl-5-vinylethylene carbonate, ethynylethylene carbonate, 4,5-diethynylethylene carbonate, 4-methyl-5-ethynylethylene carbonate, 4-vinyl-5-ethynylethylene carbonate, 4-allyl-5-ethynylethylene carbonate, phenylethylene carbonate, 4,5-diphenylethylene carbonate, 4-phenyl-5-vinylethylene carbonate, 4-allyl-5-phenylethylene carbonate, allylethylene carbonate, 4,5-diallylethylene carbonate, and 4-methyl-5-allylethylene carbonate. Ethylene carbonates substituted with substituents having aromatic rings, carbon-carbon double bonds, or carbon-carbon triple bonds may be used individually or in any ratio and combination of two or more types.

[0185] From the viewpoint of improving low-temperature power characteristics, high-rate charge / discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics, vinylene carbonate, vinylethylene carbonate, and ethynylethylene carbonate are preferred as unsaturated cyclic carbonates, vinylene carbonate and vinylethylene carbonate are more preferred, and vinylene carbonate is even more preferred.

[0186] [2-4-2. Fluorine-containing cyclic carbonates] Other fluorine-containing cyclic carbonates that can be used as compounds in this embodiment include, for example, fluorinated cyclic carbonates having alkylene groups with 2 to 6 carbon atoms, such as fluorinated ethylene carbonate; and derivatives of fluorinated cyclic carbonates having alkylene groups with 2 to 6 carbon atoms, such as fluorinated ethylene carbonate substituted with alkyl groups with 1 to 4 carbon atoms. One type of fluorine-containing cyclic carbonate may be used alone, or two or more types may be used in any ratio and combination. From the viewpoint of improving low-temperature power characteristics, high-rate charge-discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics, fluoroethylene carbonates having 1 to 4 fluorine atoms, derivatives of fluoroethylene carbonates having 1 to 8 fluorine atoms, and ethylene carbonates having fluorine-containing groups are preferred as fluorine-containing cyclic carbonates.

[0187] Examples of fluoroethylene carbonates having 1 to 4 fluorine atoms, derivatives of fluoroethylene carbonates having 1 to 8 fluorine atoms, and ethylene carbonates having a fluorine-containing group include monofluoroethylene carbonate, 4,4-difluoroethylene carbonate, 4,5-difluoroethylene carbonate, 4-fluoro-4-methylethylene carbonate, 4,5-difluoro-4-methylethylene carbonate, 4-fluoro-5-methylethylene carbonate, and 4,4-difluoro-5-methylethylene Examples include ethylene carbonate, 4-(fluoromethyl)-ethylene carbonate, 4-(difluoromethyl)-ethylene carbonate, 4-(trifluoromethyl)-ethylene carbonate, 4-(fluoromethyl)-4-fluoroethylene carbonate, 4-(fluoromethyl)-5-fluoroethylene carbonate, 4-fluoro-4,5-dimethylethylene carbonate, 4,5-difluoro-4,5-dimethylethylene carbonate, 4,4-difluoro-5,5-dimethylethylene carbonate, etc. Fluoroethylene carbonates with 1 to 4 fluorine atoms, derivatives of fluoroethylene carbonates with 1 to 8 fluorine atoms, and ethylene carbonates having a fluorine-containing group may be used individually or in any ratio and combination of two or more types. Of the fluoroethylene carbonates having 1 to 4 fluorine atoms, derivatives of fluoroethylene carbonates having 1 to 8 fluorine atoms, and ethylene carbonates having a fluorine-containing group, monofluoroethylene carbonate, 4,4-difluoroethylene carbonate, and 4,5-difluoroethylene carbonate are preferred from the viewpoint of improving low-temperature power characteristics, high-rate charge-discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics.

[0188] [2-4-3. Organic Compounds Containing Isocyanate Groups] In this embodiment, the number of isocyanate groups in the other compounds containing isocyanate groups is preferably 1 to 4, more preferably 2 to 3, and even more preferably 2, from the viewpoint of improving low-temperature power characteristics, high-rate charge / discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics.

[0189] Examples of isocyanate group-containing organic compounds include monoisocyanate compounds such as methyl isocyanate, ethyl isocyanate, butyl isocyanate, vinyl isocyanate, propargyl isocyanate, cyclohexyl isocyanate, phenyl isocyanate, 2-isocyanatoethyl acrylate, and 2-isocyanatoethyl methacrylate; and diisocyanate compounds such as monomethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, octamethylene diisocyanate, 1,4-phenylenediisocyanate, 1,3-diisocyanatopropane, 1,3-bis(isocyanatomethyl)cyclohexane, carbonyl diisocyanate, and 1,4-diisocyanato-2-fluorobutane. The isocyanate group-containing organic compounds may be used individually or in any ratio and combination of two or more. From the viewpoint of improving low-temperature power characteristics, high-rate charge-discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics, diisocyanate compounds are preferred among isocyanate group-containing organic compounds, hexamethylene diisocyanate and 1,3-bis(isocyanatomethyl)cyclohexane are more preferred, and 1,3-bis(isocyanatomethyl)cyclohexane is even more preferred.

[0190] [2-4-4. Organic Compounds Containing an Isocyanuric Acid Skeleton] Examples of organic compounds containing an isocyanuric acid skeleton that can be used as other compounds in this embodiment include the following compounds.

[0191]

[0192] The isocyanuric acid skeleton-containing organic compound may be used alone or two or more in any ratio and combination. From the viewpoint of improving low-temperature power characteristics, high-rate charge / discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics, isocyanurate compounds having saturated or unsaturated aliphatic hydrocarbon groups which may have halogen atoms are preferred, isocyanurate compounds having unsaturated aliphatic hydrocarbon groups with a carbon-carbon unsaturated bond at the terminal are more preferred, and triallyl isocyanurate is even more preferred.

[0193] [2-4-5. Sulfur-containing organic compounds] In this embodiment, the sulfur-containing organic compounds that are other compounds are preferably organic compounds having at least one S=O bond, from the viewpoint of improving low-temperature power characteristics, high-rate charge / discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics, and more preferably linear sulfonic acid esters, cyclic sulfonic acid esters, linear sulfate esters, cyclic sulfate esters, linear sulfite esters, and cyclic sulfite esters. However, in the first embodiment, the above sulfur-containing organic compounds do not include anion-containing compounds having S=O bonds and S-F bonds. Furthermore, in the third embodiment, the above sulfur-containing organic compounds do not include compounds represented by general formula (3).

[0194] Examples of sulfur-containing organic compounds include methyl fluorosulfonate, methyl methanesulfonate, ethyl methanesulfonate, propargyl methanesulfonate, busulfan, methyl methanesulfonyloxyacetate, methyl vinylsulfonate, allyl vinylsulfonate, propargyl allylsulfonate, methoxycarbonylmethyl methanedisulfonate, ethoxycarbonylmethyl methanedisulfonate, methoxycarbonylmethyl 1,3-butanedisulfonate, ethoxycarbonylmethyl 1,3-butanedisulfonate, and 1,3-butanedisulfonate. Chain-like sulfonic acid esters such as alkyl disulfonic acid esters like 1-methoxycarbonylethyl phosphate, 1-ethoxycarbonylethyl 1,3-butanedisulfonic acid, and hexafluorophenyl methanesulfonic acid; 1,3-propanesultone, 1-fluoro-1,3-propanesultone, 1-methyl-1,3-propanesultone, 1-propene-1,3-sultone, 2-propene-1,3-sultone, 1-fluoro-1-propene-1,3-sultone, 1-methyl-1-propene-1,3-sultone, 1,3-butanesultone, 2, Cyclic sulfonic acid esters such as 4-butanesultone, 1,4-butanesultone, 1,5-pentanesultone, methylenemethanedisulfate, ethylenemethanedisulfate, and 2,2-dioxide-1,2-oxathiolan-4-ylacetate; linear sulfuric acid esters such as dimethyl sulfate, ethylmethyl sulfate, and diethyl sulfate; 1,2-ethylene sulfate, 1,2-propylene sulfate, 1,3-propylene sulfate, 1,2-butylene sulfate, and 2,4,8,10-tetraoxa-3,9-dithia Cyclic sulfuric acid esters such as spiro[5,5]undecane-3,3,9,9-tetraoxide; linear sulfite esters such as dimethyl sulfite, ethyl methyl sulfite, and diethyl sulfite; cyclic sulfite esters such as 1,2-ethylene sulfite, 1,2-propylene sulfite, 1,3-propylene sulfite, and 1,2-butylene sulfite; cyclic sulfones such as 1,1-dioxidetetrahydrothiophene-3-ylmethanesulfonate and 1,1-dioxide-2,3-dihydrothiophene-3-ylmethanesulfonate;Examples include sulfonic acid esters such as butane-2,3-diylmethanesulfonate, butane-1,4-diylmethanesulfonate, and methylenemethanedisulfonate; and vinyl sulfones such as divinylsulfone, 2-bis(vinylsulfonyl)ethane, and bis(2-vinylsulfonylethyl) ether. The sulfur-containing organic compound may be used individually or in any ratio and combination of two or more. From the viewpoint of improving low-temperature power characteristics, high-rate charge / discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics, linear sulfonic acid esters, cyclic sulfonic acid esters, and cyclic sulfite esters are preferred, cyclic sulfonic acid esters and cyclic sulfite esters are more preferred, and 1,3-propanesultone, methylenemethanedisulfonate, and 1,2-ethylenesulfate are even more preferred.

[0195] [2-4-6. Phosphorus-containing organic compounds] Examples of phosphorus-containing organic compounds that can be used as other compounds in this embodiment include trimethyl phosphate, tributyl phosphate, trioctyl phosphate, trippropargyl phosphate, tris(2,2,2-trifluoroethyl) phosphate, ethyl-2-(diethoxyphosphoryl) acetate, 2-propynyl-2-(diethoxyphosphoryl) acetate, methoxypentafluorocyclotriphosphazene, ethoxypentafluorocyclotriphosphazene, phenoxypentafluorocyclotriphosphazene, ethoxyheptafluorocyclotetraphosphazene, and the like. A single phosphorus-containing organic compound may be used alone, or two or more may be used in any ratio and combination. From the viewpoint of improving low-temperature power characteristics, high-rate charge / discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics, trimethyl phosphate, tributyl phosphate, and trioctyl phosphate are preferred as phosphorus-containing organic compounds, with trimethyl phosphate being more preferred.

[0196] [2-4-7. Silicon-containing compounds] In the first aspect of this embodiment, silicon-containing compounds that become other compounds do not include anion-containing compounds having S=O bonds and S-F bonds. In the second aspect of this embodiment, silicon-containing compounds that become other compounds do not include compounds having Si-F bonds. Examples of the silicon-containing compounds that become other compounds include borate compounds such as tris(trimethylsilyl) borate, tris(trimethoxysilyl) borate, tris(triethylsilyl) borate, and tris(dimethylvinylsilyl) borate; phosphoric acid compounds such as tris(trimethylsilyl) phosphate, tris(triethylsilyl) phosphate, tris(triphenylsilyl) phosphate, tris(trimethoxysilyl) phosphate, and tris(dimethylvinylsilyl) phosphate; tris(trimethylsilyl) phosphate, tris(triethylsilyl) phosphate, tris(triphenylsilyl) phosphate, tris(trimethoxysilyl) phosphate, and tris(dimethylvinylsilyl) phosphate; tris(trimethylsilyl) phosphate, tris(triethylsilyl) phosphate, tris(triphenylsilyl) phosphate, tris(trimethoxysilyl) phosphate, and tris(dimethylvinylsilyl) phosphate. Examples include phosphorous acid compounds such as thiocyanthylvinylsilyl; sulfonic acid compounds such as trimethylsilyl methanesulfonate and trimethylsilyl tetrafluoromethanesulfonate; silane compounds such as tetramethylsilane, trimethylvinylsilane, dimethyldivinylsilane, methyltrivinylsilane, and tetravinylsilane; disilane compounds such as hexamethyldisilane, hexaethyldisilane, 1,1,2,2-tetramethyldisilane, and 1,2-diphenyltetramethyldisilane; and disiloxane compounds such as hexamethyldisiloxane, 1,3-divinyltetramethyldisiloxane, and 1,1,3,3-tetramethyl-1,3-diphenyldisiloxane. The silicon-containing compounds may be used individually or in any ratio and combination of two or more. From the viewpoint of improving low-temperature power characteristics, high-rate charge / discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics, disilane compounds and disiloxane compounds are preferred as silicon-containing compounds, disiloxane compounds are more preferred, hexamethyldisiloxane and 1,3-divinyltetramethyldisiloxane are even more preferred, and 1,3-divinyltetramethyldisiloxane is particularly preferred.

[0197] [2-4-8. Aromatic Compounds] Examples of aromatic compounds that can be used as other compounds in this embodiment include cyclohexylbenzene, tert-butylbenzene, tert-amylbenzene, 1-fluoro-4-tert-butylbenzene, biphenyl, o-terphenyl, m-terphenyl, p-terphenyl, fluorobenzene, methylphenyl carbonate, ethylphenyl carbonate, diphenyl carbonate, and the like. One aromatic compound may be used alone, or two or more may be used in any ratio and combination. From the viewpoint of improving low-temperature power characteristics, high-rate charge / discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics, biphenyl, o-terphenyl, m-terphenyl, p-terphenyl, fluorobenzene, cyclohexylbenzene, tert-butylbenzene, and tert-amylbenzene are preferred as aromatic compounds, and biphenyl, o-terphenyl, fluorobenzene, cyclohexylbenzene, and tert-amylbenzene are more preferred.

[0198] [2-4-9. [Cyano Group-Containing Organic Compounds] Other cyano group-containing organic compounds in this embodiment include, for example, monocyano compounds such as acetonitrile, propionitrile, butyronitrile, pentanenitrile, hexanenitrile, decanenitrile, undecanenitrile, dodecanenitrile, cyclohexanecarbonitride, acrylonitrile, methacrylonitrile, and crotononitrile; dicyano compounds such as succinonitrile, glutalonitrile, adiponitrile, pimeronitrile, suberonitrile, sebaconitrile, methylmalononitrile, ethylmalononitrile, bicyclohexyl-1,1-dicarbonitride, 1,4-dicyanopentane, and 1,2-didianobenzene; and tricyano compounds such as 1,2,3-propanetricarbonitride, 1,2,3-tris(2-cyanoethoxy)propane, 1,3,6-hexanetricarbonitride, 1,3,5-cyclohexanetricarbonitride, and 1,3,5-benzenetricarbonitride. The cyano group-containing organic compound may be used alone or two or more in any ratio and combination. From the viewpoint of improving low-temperature power characteristics, high-rate charge / discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics, dicyano compounds are preferred, succinonitrile and adiponitrile are more preferred, and adiponitrile is even more preferred.

[0199] [2-4-10. Acid anhydride compounds] Examples of other acid anhydride compounds in this embodiment include chain-like carboxylic acid anhydrides such as acetic anhydride, acrylic anhydride, methacrylic anhydride, cyclohexanecarboxylic acid anhydride, propic acid anhydride, benzoic acid anhydride, fluoroacetic acid anhydride, 4-fluorobenzoic acid anhydride, and propionic acetate anhydride, as well as succinic anhydride, maleic anhydride, citraconic acid anhydride, glutaric acid anhydride, itaconic acid anhydride, fluorosuccal anhydride, allyl succinic acid anhydride, 1,2-oxathiolan-5-one = 2,2-dioxide, and 1,2,6-oxadithiane = 2,2,6,6-tetraoxide. One acid anhydride compound may be used alone, or two or more may be used in any ratio and combination. From the viewpoint of improving low-temperature power characteristics, high-rate charge / discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics, methacrylic anhydride, succinic anhydride, maleic anhydride, and allyl succinic anhydride are preferred as acid anhydride compounds, with succinic anhydride and allyl succinic anhydride being more preferred.

[0200] [2-4-11. Triple Bond-Containing Compounds] Examples of triple bond-containing compounds that can be used as other compounds in this embodiment include 2-propynylmethyl carbonate, 2-propynyl acetate, 2-propynyl formate, 2-propynyl methacrylate, 2-propynyl methanesulfonic acid, 2-propynyl vinylsulfonic acid, 2-propynyl 2-(methanesulfonyloxy)propionic acid, di(2-propynyl)oxalate, 2-butyne-1,4-diylmethanesulfonate, 2-butyne-1,4-diyldiformate, 1H-imidazole-1-carboxylic acid propargyl, and the like. A single triple bond-containing compound may be used alone, or two or more may be used in any ratio and combination. From the viewpoint of improving low-temperature power characteristics, high-rate charge-discharge characteristics, impedance characteristics, high-temperature storage characteristics, and cycle characteristics, the triple bond-containing compounds are preferably 2-propynylmethyl carbonate, 2-propynyl methacrylate, 2-propynyl methanesulfonic acid, 2-propynyl vinylsulfonic acid, di(2-propynyl)oxalate, and 2-butyne-1,4-diylmethanesulfonate, and more preferably 2-propynyl methanesulfonic acid, 2-propynyl vinylsulfonic acid, di(2-propynyl)oxalate, and 2-butyne-1,4-diylmethanesulfonate.

[0201] [2-5. Method for Producing Electrolyte] The method for producing an electrolyte according to the first aspect of this embodiment includes the step of dissolving an anion-containing compound having an S=O bond and an S-F bond, or a composition containing an anion-containing compound having an S=O bond and an S-F bond, and an electrolyte in a non-aqueous solvent. The obtained electrolyte is used in a battery having a negative electrode containing niobium. The anion-containing compound is preferably an anion-containing compound having an S=O bond and an S-F bond, and having a fluorosulfonic acid anion as a constituent component. The method for producing an electrolyte according to the second aspect of this embodiment includes the step of dissolving a compound having an Si-F bond, or a composition containing a compound having an Si-F bond, and an electrolyte in a non-aqueous solvent. The obtained electrolyte is used in a battery having a negative electrode containing niobium. The method for producing an electrolyte according to the third aspect of this embodiment includes the step of dissolving a compound represented by general formula (3), or a composition containing a compound represented by general formula (3), and an electrolyte in a non-aqueous solvent. The obtained electrolyte is used in a battery having a negative electrode containing niobium.

[0202] In the first embodiment, the dissolving step includes a step of dissolving an anion-containing compound having S=O and S-F bonds or a composition containing an anion-containing compound having S=O and S-F bonds in a non-aqueous solvent, or alternatively, a step of dissolving the raw materials of each component constituting the composition containing an anion-containing compound having S=O and S-F bonds or an anion-containing compound having S=O and S-F bonds in a non-aqueous solvent to generate a composition containing an anion-containing compound having S=O and S-F bonds or an anion-containing compound having S=O and S-F bonds in an electrolyte. Furthermore, the method for producing the electrolyte according to this embodiment also includes a step of dissolving the electrolyte in a non-aqueous solvent, but alternatively, a step of dissolving the raw materials of the electrolyte in a non-aqueous solvent to generate the electrolyte in an electrolyte.

[0203] In a second embodiment, the dissolving step may include a step of dissolving a compound having an Si-F bond or a composition containing a compound having an Si-F bond in a non-aqueous solvent, or alternatively, a step of dissolving the raw materials of each component constituting the compound having an Si-F bond or a composition containing a compound having an Si-F bond in a non-aqueous solvent to generate a compound having an Si-F bond or a composition containing a compound having an Si-F bond in an electrolyte. Furthermore, the method for producing the electrolyte according to this embodiment also includes a step of dissolving the electrolyte in a non-aqueous solvent, but alternatively, a step of dissolving the raw materials of the electrolyte in a non-aqueous solvent to generate the electrolyte in an electrolyte.

[0204] In a third embodiment, the dissolving step may include a step of dissolving the compound represented by general formula (3) or a composition containing the compound represented by general formula (3) in a non-aqueous solvent, or alternatively, a step of dissolving the raw materials of each component constituting the compound represented by general formula (3) or a composition containing the compound represented by general formula (3) in a non-aqueous solvent to generate the compound represented by general formula (3) or a composition containing the compound represented by general formula (3) in an electrolyte. Furthermore, the method for producing the electrolyte according to this embodiment also includes a step of dissolving the electrolyte in a non-aqueous solvent, but alternatively, a step of dissolving the raw materials of the electrolyte in a non-aqueous solvent to generate the electrolyte in an electrolyte.

[0205] In the method for producing an electrolyte according to the first aspect of this embodiment, the anion-containing compound having an S=O bond and an S-F bond, or in a composition containing the anion-containing compound having an S=O bond and an S-F bond, is described in the same way as the anion-containing compound having an S=O bond and an S-F bond described in [1A-1. Anion-containing compound having an S=O bond and an S-F bond] above, and the preferred aspects are also the same.

[0206] The compound having an Si-F bond in the method for producing an electrolyte according to the second aspect of this embodiment, or in a composition containing a compound having an Si-F bond, is described in the same way as the compound having an Si-F bond in [1B-1. Compound having an Si-F bond] above, and the preferred embodiment is also the same.

[0207] The compound represented by general formula (3) in the method for producing an electrolyte according to the third aspect of this embodiment, or the compound represented by general formula (3) in a composition containing the compound represented by general formula (3), is described in the same way as the compound represented by general formula (3) in [1C-1. Compound represented by general formula (3)] above, and the preferred embodiment is also the same.

[0208] The electrolyte in the method for producing the electrolyte according to this embodiment is described in the same way as the electrolyte in [2-2. Electrolytes] above, and the preferred embodiment is also the same.

[0209] The non-aqueous solvent in the method for producing the electrolyte according to this embodiment is described in the same way as the non-aqueous solvent in [2-3. Non-aqueous solvent] above, and the preferred embodiments are also the same.

[0210] In the first embodiment, the method for dissolving the composition and electrolyte containing an anion-containing compound having S=O and S-F bonds or an anion-containing compound having S=O and S-F bonds in a non-aqueous solvent is not particularly limited. The composition and electrolyte may be produced by sequentially dissolving each in a non-aqueous solvent, or by dissolving them simultaneously in a non-aqueous solvent. Alternatively, the electrolyte dissolved at a high concentration in a non-aqueous solvent and the composition containing an anion-containing compound having S=O and S-F bonds or an anion-containing compound having S=O and S-F bonds dissolved at a high concentration in a non-aqueous solvent may be produced by sequentially mixing each in a non-aqueous solvent.

[0211] In the second embodiment, the method for dissolving the compound having an Si-F bond or a composition containing a compound having an Si-F bond, or the electrolyte, in a non-aqueous solvent is not particularly limited. The compound having an Si-F bond or a composition containing a compound having an Si-F bond, and the electrolyte may be produced by sequentially dissolving them in a non-aqueous solvent, or by dissolving them in a non-aqueous solvent simultaneously. Alternatively, the electrolyte dissolved in a non-aqueous solvent at a high concentration, and the compound having an Si-F bond or a composition containing a compound having an Si-F bond dissolved in a non-aqueous solvent at a high concentration, may be produced by sequentially mixing them in a non-aqueous solvent.

[0212] In a third embodiment, the method for dissolving the compound represented by general formula (3) or a composition containing the compound represented by general formula (3), or an electrolyte in a non-aqueous solvent is not particularly limited. The compound represented by general formula (3) or a composition containing the compound represented by general formula (3), and the electrolyte may be produced by sequentially dissolving them in a non-aqueous solvent, or by dissolving them in a non-aqueous solvent simultaneously. Alternatively, the electrolyte dissolved at a high concentration in a non-aqueous solvent, and the compound represented by general formula (3) or a composition containing the compound represented by general formula (3), dissolved at a high concentration in a non-aqueous solvent, may be produced by sequentially mixing them in a non-aqueous solvent.

[0213] [2-6. Use of Electrolyte] A method of using the electrolyte according to the first aspect of this embodiment involves using an electrolyte comprising an anion-containing compound having S=O and S-F bonds, or a composition containing an anion-containing compound having S=O and S-F bonds, an electrolyte, and a non-aqueous solvent in a battery having a negative electrode containing niobium. The anion-containing compound is preferably an anion-containing compound having S=O and S-F bonds and having fluorosulfonic acid anion as a constituent component. The specific method of use is not particularly limited, but for example, one method is to apply an electrolyte comprising an anion-containing compound having S=O and S-F bonds, or a composition containing an anion-containing compound having S=O and S-F bonds, to a battery.

[0214] A method of using the electrolyte according to the second aspect of this embodiment involves using an electrolyte comprising a compound having an Si-F bond or a composition containing a compound having an Si-F bond, an electrolyte, and a non-aqueous solvent in a battery having a negative electrode containing an element of niobium. The specific method of use is not particularly limited, but for example, one method is to apply an electrolyte containing a compound having an Si-F bond or a composition containing a compound having an Si-F bond to the battery.

[0215] A method of using the electrolyte according to the second aspect of this embodiment involves using an electrolyte comprising a compound having an Si-F bond or a composition containing a compound having an Si-F bond, an electrolyte, and a non-aqueous solvent in a battery having a negative electrode containing an element of niobium. The specific method of use is not particularly limited, but for example, one method is to apply an electrolyte containing a compound having an Si-F bond or a composition containing a compound having an Si-F bond to the battery.

[0216] A third aspect of this embodiment involves using an electrolyte comprising a compound represented by general formula (3) or a composition containing the compound represented by general formula (3), an electrolyte, and a non-aqueous solvent in a battery having a negative electrode containing niobium. The specific method of use is not particularly limited, but for example, one method is to apply an electrolyte comprising a compound represented by general formula (3) or a composition containing the compound represented by general formula (3) to the battery.

[0217] [3. Battery] The battery according to this embodiment includes a positive electrode, a negative electrode containing niobium, and an electrolyte.

[0218] [3-1. Electrolyte] The electrolyte in this embodiment is described in the same way as the electrolyte described in [2. Electrolyte] above, and the preferred embodiment is also the same. Other electrolytes may be used in combination, as long as they do not significantly impair the effects of the present invention.

[0219] [3-2. Positive Electrode] In this embodiment, the positive electrode includes positive electrode active material in at least a portion of the surface of the current collector.

[0220] [3-2-1. Positive Electrode Active Material] The positive electrode active material in this embodiment is not particularly limited as long as it is capable of electrochemically intercalating and releasing metal ions. Examples of positive electrode active materials include lithium transition metal compounds, sodium transition metal compounds, potassium transition metal compounds, etc. The positive electrode active material may be used alone, or two or more may be used in any ratio and combination. From the viewpoint of increasing the energy density of the battery, lithium transition metal compounds, sodium transition metal compounds, and potassium transition metal compounds are preferred as positive electrode active materials, and lithium transition metal compounds are more preferred.

[0221] [3-2-1-1. Lithium Transition Metal Compounds] The lithium transition metal compound that serves as the positive electrode active material in this embodiment is not particularly limited as long as it is a compound having a structure that allows for insertion, removal, and insertion of lithium ions. Examples of lithium transition metal compounds include lithium transition metal sulfides, lithium transition metal phosphate compounds, lithium transition metal silicate compounds, lithium transition metal borate compounds, and lithium transition metal composite oxides. One lithium transition metal compound may be used alone, or two or more may be used in any ratio and combination. From the viewpoint of increasing the energy density of the battery, lithium transition metal phosphate compounds and lithium transition metal composite oxides are preferred, and lithium transition metal composite oxides are more preferred.

[0222] Examples of lithium transition metal composite oxide structures include spinel structures, olivine structures, and layered structures. From the viewpoint of battery capacity and durability, spinel structures, olivine structures, and layered structures are preferred for lithium transition metal composite oxides, and from the viewpoint of increasing battery capacity, layered structures are more preferred.

[0223] Lithium transition metal composite oxides having a spinel structure allow for three-dimensional diffusion of lithium ions and are generally represented by the following compositional formula (I).

[0224]

[0225] (0.8≦a in compositional formula (I) １ ≤ 1.5, 1.9 ≤ b １ ≤ 2.1, M １ (It contains at least one transition metal element, excluding Li.)

[0226] M １ Examples include Ni, Co, Mn, V, Al, etc. １ One type may be used alone, or two or more types may be used in any ratio and combination. １ From the viewpoint of improving the battery's cycle performance, Ni, Co, and Mn are preferred, and Ni and Mn are more preferred.

[0227] Examples of lithium transition metal composite oxides having a spinel structure include LiMn ２ O ４ LiCoMnO ４ LiNi ０．５ Mn １．５ O ４ LiCoVO ４ Examples include LiMn. A lithium transition metal composite oxide having a spinel structure may be used alone, or two or more may be used in any ratio and combination. From the viewpoint of improving the battery cycle performance, LiMn ２ O ４ LiNi ０．５ Mn １．５ O ４ LiNi ０．５ Mn １．５ O ４ This is preferable.

[0228] Lithium transition metal composite oxides having an olivine structure allow for three-dimensional diffusion of lithium ions and are generally represented by the following compositional formula (II).

[0229]

[0230] (0.8≦a in compositional formula (II) ２ ≤ 1.5, 0.9 ≤ b ２ ≤ 1.1, M ２ (It contains at least one transition metal element, excluding Li.)

[0231] M ２ Examples include Fe, Ni, Co, Mn, Al, etc. ２ One type may be used alone, or two or more types may be used in any ratio and combination. ２ From the viewpoint of improving the battery's cycle performance, Fe, Ni, Co, and Mn are preferred, with Fe and Mn being more preferred.

[0232] Examples of lithium transition metal composite oxides having an olivine structure include LiFePO ４Examples include the following. A lithium transition metal composite oxide having an olivine structure may be used alone, or two or more may be used in any ratio and combination. From the viewpoint of improving the battery cycle performance, the lithium transition metal composite oxide having an olivine structure is LiFePO ４ It is preferable.

[0233] Lithium transition metal composite oxides having a layered structure allow for three-dimensional diffusion of lithium ions and are generally represented by the following compositional formula (III).

[0234]

[0235] (0.8≦a in compositional formula (III) ３ ≤ 1.5, 0.5 ≤ b ３ ≤ 1.1, M ３ (It contains at least one transition metal element, excluding Li.)

[0236] M ３ Examples include Ni, Co, Mn, Al, Mg, Zr, Fe, Ti, Er, etc. ３ One type may be used alone, or two or more types may be used in any ratio and combination. ３ From the viewpoint of improving the battery's cycle performance, Ni, Co, Mn, Al, Mg, and Zr are preferred, and Ni, Co, Mn, and Al are more preferred.

[0237] Examples of lithium transition metal composite oxides having a layered structure include LiCoO ２ LiNiO ２ LiNi ０．９ Co ０．０５ Mn ０．０５ O ２ LiNi ０．８５ Co ０．１ Al ０．０５ O ２ LiNi ０．８ Co ０．１５ Al ０．０５ O ２ LiNi ０．３３ Co ０．３３ Mn ０．３３ O ２ Li １．０５ Ni ０．３３Co ０．３３ Mn ０．３３ O ２ LiNi ０．５ Co ０．３ Mn ０．２ O ２、 LiNi ０．５ Co ０．２ Mn ０．３ O ２ Li １．０５ Ni ０．５ Co ０．２ Mn ０．３ O ２ LiNi ０．６ Co ０．２ Mn ０．２ O ２ LiNi ０．８ Co ０．１ Mn ０．１ O ２ , Li[Li １／３ Mn ２／３ ]O ２ Examples include solid solutions thereof. A lithium transition metal composite oxide having a layered structure may be used alone, or two or more may be used in any ratio and combination.

[0238] From the viewpoint of increasing battery capacity, lithium transition metal composite oxides having a layered structure are preferred if they are represented by the following compositional formula (IV), and more preferably if they are represented by the following compositional formula (V).

[0239]

[0240] (0.8≦a in compositional formula (IV) ４ ≤ 1.1, 0.3 ≤ b ４ ≤0.98, 0.0 ≤c ４ ≤ 0.7, 0.9 ≤ b ４ +c ４ ≤ 1.1, M ４ (This is at least one metallic element selected from the group consisting of Co, Mn, Al, Mg, Zr, Fe, Ti, and Er.)

[0241]

[0242] (0.8≦a in compositional formula (V) ５ ≤ 1.1, 0.3 ≤ b ５≤0.98, 0.01 ≤c ５ ≤0.7, 0.01 ≤d ５ ≤ 0.6, 0.9 ≤ b ５ +c ５ +d ５ ≤ 1.1, M ５ (This is at least one metallic element selected from the group consisting of Mn, Al, Mg, Zr, Fe, Ti, and Er.)

[0243] M in the composition formula (IV) ４ This element is at least one metal element selected from the group consisting of Co, Mn, Al, Mg, Zr, Fe, Ti, and Er. From the viewpoint of improving the structural stability of lithium transition metal oxides and suppressing structural degradation during repeated charging and discharging, Co, Mn, and Al are preferred, and Co and Mn are more preferred.

[0244] b in the empirical formula (IV) ４ It is 0.3 or higher, and from the viewpoint of improving the battery's cycle performance, it is preferably 0.4 or higher, and more preferably 0.5 or higher. Also, b ４ The value is 0.98 or less, and from the viewpoint of battery safety, 0.97 or less is preferred, and 0.96 or less is more preferred.

[0245] Examples of lithium transition metal composite oxides represented by compositional formula (IV) include LiNi ０．９ Co ０．０５ Mn ０．０５ O ２ LiNi ０．８５ Co ０．１ Al ０．０５ O ２ LiNi ０．８ Co ０．１５ Al ０．０５ O ２ LiNi ０．３ Co ０．３ Mn ０．３ O ２ LiNi ０．５ Co ０．２ Mn ０．３ O ２ Li １．０５ Ni ０．５ Co ０．２ Mn ０．３ O ２ LiNi ０．６ Co０．２ Mn ０．２ O ２ LiNi ０．８ Co ０．１ Mn ０．１ O ２ LiNi ０．９１ Co ０．０６ Mn ０．０３ O ２ LiNi ０．９１ Co ０．０６ Al ０．０３ O ２ LiNi ０．９ Co ０．０３ Al ０．０７ O ２ LiNi ０．６１ Co ０．２ Mn ０．１９ O ２ Examples include the following. The lithium transition metal composite oxide represented by compositional formula (IV) may be used alone, or two or more may be used in any ratio and combination.

[0246] M in the composition formula (V) ５ This element is at least one metal element selected from the group consisting of Mn, Al, Mg, Zr, Fe, Ti, and Er. From the viewpoint of improving the structural stability of lithium transition metal oxides and suppressing structural degradation during repeated charging and discharging, Mn and Al are preferred, and Mn is more preferred.

[0247] b in the empirical formula (V) ５ b is 0.3 or higher, preferably 0.4 or higher, and more preferably 0.5 or higher, from the viewpoint of increasing the energy density of the battery. ５ The value is 0.98 or less, and from the viewpoint of battery safety, 0.97 or less is preferred, and 0.96 or less is more preferred.

[0248] d in the empirical formula (V) ５ It is 0.01 or greater, and from the viewpoint of battery safety, 0.1 or greater is preferred. Also, d ５ The value is 0.6 or less, and from the viewpoint of increasing the energy density of the battery, 0.5 or less is preferable.

[0249] Examples of lithium transition metal composite oxides represented by compositional formula (V) include LiNi ０．９ Co０．０５ Mn ０．０５ O ２ LiNi ０．８５ Co ０．１ Al ０．０５ O ２ LiNi ０．８ Co ０．１５ Al ０．０５ O ２ LiNi ０．３ Co ０．３ Mn ０．３ O ２ LiNi ０．５ Co ０．２ Mn ０．３ O ２ Li １．０５ Ni ０．５ Co ０．２ Mn ０．３ O ２ LiNi ０．６ Co ０．２ Mn ０．２ O ２ LiNi ０．８ Co ０．１ Mn ０．１ O ２ LiNi ０．９１ Co ０．０６ Mn ０．０３ O ２ LiNi ０．９１ Co ０．０６ Al ０．０３ O ２ LiNi ０．９ Co ０．０３ Al ０．０７ O ２ LiNi ０．６１ Co ０．２ Mn ０．１９ O ２ Examples include the following. The lithium transition metal composite oxide represented by compositional formula (V) may be used alone, or two or more may be used in any ratio and combination.

[0250] The lithium transition metal composite oxide may further contain elements other than those included in the aforementioned compositional formulas (I) to (V) (other elements).

[0251] [3-2-1-2. Surface Coating] In this embodiment, the positive electrode active material may be one in which a substance with a different composition from the positive electrode active material (surface-adhered substance) is attached to the surface of the positive electrode active material. Examples of surface-adhered substances include oxides such as aluminum oxide; sulfates such as lithium sulfate; and carbonates such as lithium carbonate. One type of surface-adhered substance may be used alone, or two or more types may be used in any ratio and combination. From the viewpoint of battery safety, lithium carbonate is preferred as the surface-adhered substance. The surface-adhered substance can be attached to the surface of the positive electrode active material by dissolving it in a solvent or dispersing it in a dispersion medium and impregnating the positive electrode active material with it.

[0252] The content of surface-adhered material relative to the total positive electrode active material is preferably 1 μmol / g or more and 1 mmol / g or less. Here, from the viewpoint of battery safety, the above content is preferably 1 μmol / g or more, and more preferably 10 μmol / g or more. Furthermore, from the viewpoint of increasing the energy density of the battery, the above content is preferably 1 mmol / g or less, and more preferably 0.5 mmol / g or less. In this specification, surface-adhered material attached to the surface of the positive electrode active material is also included in the positive electrode active material.

[0253] [3-2-2. Method for Manufacturing the Positive Electrode] Examples of methods for manufacturing the positive electrode in this embodiment include a method of obtaining a positive electrode by forming a positive electrode active material layer on a current collector by pressure bonding, and a method of obtaining a positive electrode by forming a positive electrode active material layer on a current collector by coating. From the viewpoint of a simple manufacturing process and excellent productivity, the method of obtaining a positive electrode by forming a positive electrode active material layer on a current collector by coating is preferred.

[0254] The positive electrode active material layer further includes a positive electrode active material and a binder, as well as, if necessary, a conductive material and a thickening agent.

[0255] In the method of obtaining a positive electrode by forming a positive electrode active material layer on a current collector by pressure bonding, a preferred method is one in which, from the viewpoint of a simple manufacturing process and excellent productivity, a positive electrode active material and binder, as well as conductive material and thickener as needed, are dry-mixed to form a sheet, and then pressure-bonded onto a positive electrode current collector to obtain the positive electrode.

[0256] In the method of obtaining a positive electrode by forming a positive electrode active material layer on a current collector by coating, a method is preferred from the viewpoint of simplicity of the manufacturing process and excellent productivity, in which, in addition to the positive electrode active material and binder, a conductive material and a thickener are further dissolved in a solvent or dispersed in a dispersion medium as needed, and the mixture is coated onto the positive electrode current collector and dried to obtain the positive electrode.

[0257] [3-2-2-1. Positive Electrode Active Material Layer] The content of positive electrode active material in the positive electrode active material layer is preferably 80 to 99.5% by mass. Here, from the viewpoint of increasing the energy density of the battery, the above content is preferably 80% by mass or more, and more preferably 90% by mass or more. Also, from the viewpoint of improving the handling of the positive electrode, the above content is preferably 99.5% by mass or less, and more preferably 99% by mass or less. Here, if two or more types of positive electrode active materials are included, the above content refers to the total content of those materials. In this specification, the identification of positive electrode active material and the content of positive electrode active material are measured by high-frequency inductively coupled plasma (ICP) emission spectroscopy after wet decomposition of the sample. If it is difficult to identify positive electrode active material or determine the content of positive electrode active material by high-frequency inductively coupled plasma (ICP) emission spectroscopy alone, other analyses such as X-ray photoelectron spectroscopy (XPS), X-ray fluorescence (XRF) analysis, and energy-dispersive X-ray spectroscopy (EDS) analysis may be used in combination.

[0258] Examples of binders include fluororesins such as polyvinyl fluoride, polyvinylidene fluoride, and polytetrafluoroethylene; cyano group-containing resins such as polyacrylonitrile and polyvinylidene cyanide; and modified versions thereof, derivatives, random copolymers, alternating copolymers, graft copolymers, and block copolymers. One binder may be used alone, or two or more may be used in any ratio and combination. From the viewpoint of weather resistance, chemical resistance, heat resistance, and flame retardancy, fluororesins and cyano group-containing resins are preferred as binders.

[0259] When a resin is used as a binder, the weight-average molecular weight of the resin is preferably 10,000 to 3,000,000. Here, from the viewpoint of improving the strength of the positive electrode, the weight-average molecular weight is preferably 10,000 or more, more preferably 50,000 or more, and even more preferably 100,000 or more. Furthermore, from the viewpoint of ease of forming the positive electrode, the weight-average molecular weight is preferably 3,000,000 or less, more preferably 950,000 or less, and even more preferably 900,000 or less.

[0260] The binder content in the positive electrode active material layer is preferably 0.1 to 20% by mass. Here, from the viewpoint of battery durability, the above content is preferably 0.1% by mass or more, and more preferably 0.5% by mass or more. Furthermore, from the viewpoint of increasing the energy density of the battery, the above content is preferably 20% by mass or less, and more preferably 10% by mass or less.

[0261] Examples of conductive materials include metallic materials such as copper and nickel; graphite such as natural graphite and artificial graphite; carbon black such as acetylene black; and carbon-based materials such as amorphous carbon such as needle coke. One type of conductive material may be used alone, or two or more types may be used in any ratio and combination. From the viewpoint of enhancing conductivity, carbon black is preferred as the conductive material.

[0262] When the positive electrode active material layer contains a conductive material, the content of the conductive material in the positive electrode active material layer is preferably 0.01 to 15% by mass. Here, from the viewpoint of increasing conductivity, the above content is preferably 0.01% by mass or more, and more preferably 0.1% by mass or more. Furthermore, from the viewpoint of increasing the energy density of the battery, the above content is preferably 15% by mass or less, and more preferably 10% by mass or less.

[0263] From the viewpoint of increasing the packing density of the positive electrode active material, it is preferable to compact the positive electrode active material layer using a hand press, roller press, or the like. The density of the positive electrode active material layer is 1.5 to 4.5 g / cm³. ３ This is preferable. Here, from the viewpoint of increasing the energy density of the battery, the above density is 1.5 g / cm³. ３ The above is preferable, specifically 2.0 g / cm³. ３ The above is more preferable. Furthermore, from the viewpoint of impregnating with electrolyte, the density is 4.5 g / cm³.３ The following is preferable: 4.0 g / cm³ ３ The following are preferable.

[0264] The thickness of the positive electrode active material layer is preferably 10 to 500 μm. Here, from the viewpoint of increasing the energy density of the battery, the thickness is preferably 10 μm or more, and more preferably 15 μm or more. Also, from the viewpoint of improving the rate characteristics of the battery, the thickness is preferably 500 μm or less, and more preferably 300 μm or less. The positive electrode active material layer may be formed on one surface of the current collector, or on both surfaces of the current collector.

[0265] [3-2-2-2. Current Collector] Examples of materials for the current collector include metal materials such as aluminum, stainless steel, nickel plating, titanium, and tantalum. From the viewpoint of increasing the energy density of the battery, aluminum is preferred as the material for the current collector.

[0266] Examples of current collector shapes include metal foil, metal cylinder, metal coil, metal plate, metal thin film, expanded metal, punched metal, and foamed metal. From the viewpoint of improving the handling of the positive electrode, metal foil and metal thin film are preferred as current collector shapes. The metal thin film may be formed in a mesh shape.

[0267] When the shape of the current collector is plate-shaped or film-shaped, the thickness of the current collector is preferably 1 μm or more and 1 mm or less. Here, from the viewpoint of improving the handling of the positive electrode, the above thickness is preferably 1 μm or more, and more preferably 2 μm or more. Furthermore, from the viewpoint of increasing the energy density of the battery, the above thickness is preferably 1 mm or less, and more preferably 0.5 mm or less.

[0268] [3-2-3. Surface Coating of the Positive Electrode] The positive electrode may be one in which a substance with a different composition from the positive electrode active material (surface-adhered substance) is attached to the surface of the positive electrode. The same explanation as for the surface-adhered substance in [3-2-1-2. Surface Coating] applies to the surface-adhered substance on the surface of the positive electrode, and the preferred embodiments are also the same. In this specification, the surface-adhered substance attached to the surface of the positive electrode is also included in the positive electrode.

[0269] [3-3. Negative Electrode] The negative electrode in this embodiment may contain niobium. The negative electrode has a negative electrode active material on at least a part of the current collector surface that is capable of electrochemically intercalating and releasing metal ions, but from the viewpoint of increasing the charge / discharge capacity during rapid charge / discharge, it is preferable that the negative electrode active material contains niobium.

[0270] [3-3-1. Negative Electrode Active Material] [3-3-1-1. Metal Oxide Containing Niobium Metal] In this embodiment, the negative electrode active material preferably contains the element niobium. Specific examples of negative electrode active materials containing the element niobium include metal oxides containing niobium metal. Metal oxides containing niobium metal are generally represented by the following compositional formula (I').

[0271]

[0272] (In the empirical formula (I'), M represents at least one element selected from Ti, W, Fe, Al, Cr, Ga, P, V, and Mo, where 0 ≤ a ≤ 2.00, 0 < b ≤ 1.00, 0 ≤ c < 1.00, 1.50 ≤ d ≤ 3.50, and b + c = 1.)

[0273] Among metal oxides containing niobium metal, from the viewpoint of increasing the gravimetric energy density, it is preferable that a to d in the above composition formula (I') are 0 ≤ a ≤ 2.00, 0.30 < b ≤ 1.00, 0 ≤ c < 0.45, 1.50 ≤ d ≤ 3.50 and b + c = 1; more preferably 0 ≤ a ≤ 2.00, 0.50 < b ≤ 1.00, 0 ≤ c < 0.45, 1.50 ≤ d ≤ 3.50 and b + c = 1; and even more preferably 0 ≤ a ≤ 2.00, 0.55 < b ≤ 1.00, 0 ≤ c < 0.45, 1.50 ≤ d ≤ 3.50 and b + c = 1.

[0274] Furthermore, metal oxides containing niobium metal represented by the composition formula (I') include niobium metal oxide when c is 0, niobium titanium composite oxide containing Ti as M, niobium tungsten composite oxide containing W as M, and niobium metal composite oxide containing a metal other than Ti and W as M.

[0275] A specific example of a niobium metal oxide is Li ａ Nb １．００ O ２．５０(Nb ２ O ５ ), Li ａ Nb １．００ O ２．４２ (Nb １２ O ２９ ), Li ａ Nb １．００ O ２．００ (NbO ２ ), Li ａ Nb １．００ O １．５０ (Nb ２ O ３ ) are some examples. Among the above, Li ａ Nb １．００ O ２．５０ (Nb ２ O ５ ), Li ａ Nb １．００ O ２．４２ (Nb １２ O ２９ ) is preferred, Li ａ Nb １．００ O ２．５０ (Nb ２ O ５ ) is more preferable. A specific example of a niobium-titanium composite oxide is Li ａ Nb ０．６７ Ti ０．３３ O ２．３３ (TiNb ２ O ７ ), Li ａ Nb ０．８３ Ti ０．１７ O ２．４２ (Ti ２ Nb １０ O ２９ ), Li ａ Nb ０．９６ Ti ０．０４ O ２．５８ (TiNb ２４ O ６２ ) are some examples. Among the above, Li ａ Nb ０．６７ Ti ０．３３ O ２．３３ (TiNb ２ O ７ ), Li ａ Nb ０．８３ Ti ０．１７ O ２．４２ (Ti ２ Nb１０ O ２９ ) is preferred, Li ａ Nb ０．６７ Ti ０．３３ O ２．３３ (TiNb ２ O ７ ) is more preferable. A specific example of a niobium tungsten composite oxide is Li ａ Nb ０．９２ W ０．０８ O ２．５４ (Nb １２ WO ３３ ), Li ａ Nb ０．８２ W ０．１８ O ２．５９ (Nb １４ W ３ O ４４ ), Li ａ Nb ０．７６ W ０．２４ O ２．６２ (Nb １６ W ５ O ５５ ), Li ａ Nb ０．６９ W ０．３１ O ２．６５ (Nb １８ W ８ O ６９ ) are some examples. Among the above, Li ａ Nb ０．７６ W ０．２４ O ２．６２ (Nb １６ W ５ O ５５ ), Li ａ Nb ０．６９ W ０．３１ O ２．６５ (Nb １８ W ８ O ６９ ) is preferred. Specific examples of niobium metal composite oxides containing a metal other than Ti and W as M include Li ａ Nb ０．９２ Fe ０．０８ O ２．４２ (FeNb １１ O ２９ ), Li ａ Nb ０．９２ Al ０．０８ O ２．４２ (AlNb １１ O２９ ), Li ａ Nb ０．９２ Cr ０．０８ O ２．４２ (CrNb １１ O ２９ ), Li ａ Nb ０．９２ Ga ０．０８ O ２．４２ (GaNb １１ O ２９ ), Li ａ Nb ０．９０ P ０．１０ O ２．５０ (PNb ９ O ２５ ), Li ａ Nb ０．９０ V ０．１０ O ２．５０ (VNb ９ O ２５ Examples include:

[0276] Among the above, niobium metal oxide, niobium titanium composite oxide, and niobium tungsten composite oxide are preferred, Li ａ Nb １．００ O ２．５０ (Nb ２ O ５ ), Li ａ Nb １．００ O ２．４２ (Nb １２ O ２９ ), Li ａ Nb ０．６７ Ti ０．３３ O ２．３３ (TiNb ２ O ７ ), Li ａ Nb ０．８３ Ti ０．１７ O ２．４２ (Ti ２ Nb １０ O ２９ ), Li ａ Nb ０．７６ W ０．２４ O ２．６２ (Nb １６ W ５ O ５５ ), Li ａ Nb ０．６９ W ０．３１ O ２．６５ (Nb １８ W８ O ６９ ) is particularly preferable.

[0277] [3-3-1-2. Other Negative Electrode Active Materials] In this embodiment, the negative electrode active material may include other negative electrode active materials in addition to the negative electrode active material containing niobium, as long as the effects of the present invention are not impaired. Other negative electrode active materials are not particularly limited as long as they are capable of electrochemically intercalating and releasing metal ions, but examples include carbon-based materials and metal materials. Conventionally known carbon-based materials and metal materials can be used. Here, the metal elements constituting the metal material are metal elements and / or metalloid elements. One type of other negative electrode active material may be used alone, or two or more types may be used in any ratio and combination. From the viewpoint of cycle characteristics, continuous charging characteristics and safety, carbon-based materials, metal materials, and mixtures of carbon-based materials and metal materials are preferred as other negative electrode active materials.

[0278] The identification and content measurement of the negative electrode active material are performed by ICP emission spectroscopy after alkali fusion of the sample.

[0279] [3-3-2. Method for Manufacturing the Negative Electrode] The method for manufacturing the negative electrode in this embodiment is not particularly limited, but examples include a method of obtaining a negative electrode by forming a negative electrode active material layer on a current collector by pressure bonding, and a method of obtaining a negative electrode by forming a negative electrode active material layer on a current collector by coating. From the viewpoint of a simple manufacturing process and excellent productivity, the method of obtaining a negative electrode by forming a negative electrode active material layer on a current collector by coating is preferred.

[0280] The negative electrode active material layer further includes, as necessary, a conductive material, a thickener, and a filler, in addition to the negative electrode active material and a binder.

[0281] In the method of obtaining a negative electrode by forming a negative electrode active material layer on a current collector by pressure, a preferred method is one in which, from the viewpoint of a simple manufacturing process and excellent productivity, a negative electrode active material and binder, as well as conductive material, thickener, and filler as needed, are dry-mixed to form a sheet, and then pressure-bonded onto a negative electrode current collector to obtain the negative electrode.

[0282] In the method of obtaining a negative electrode by forming a negative electrode active material layer on a current collector by coating, a preferred method is one in which, from the viewpoint of a simple manufacturing process and excellent productivity, a slurry is obtained by coating the negative electrode current collector with a slurry in which a negative electrode active material and binder are dispersed in a dispersion medium, as needed, a conductive material, a thickener and a filler, and then drying it.

[0283] [3-3-2-1. Negative Electrode Active Material Layer] The content of negative electrode active material in the negative electrode active material layer is preferably 80 to 99.5% by mass. Here, from the viewpoint of increasing the energy density of the battery, the above content is preferably 80% by mass or more, and more preferably 90% by mass or more. Also, from the viewpoint of improving the handling of the negative electrode, the above content is preferably 99.5% by mass or less, and more preferably 99% by mass or less. Here, if two or more types of negative electrode active materials are included, the above content refers to the total content of those materials. In this specification, the identification of negative electrode active materials and the content of negative electrode active materials are measured by high-frequency inductively coupled plasma (ICP) emission spectroscopy after alkali fusion of the sample.

[0284] Examples of binders include rubbery polymers such as styrene-butadiene rubber (SBR), isoprene rubber, butadiene rubber, fluororubber, acrylonitrile-butadiene rubber (NBR), and ethylene-propylene rubber; and fluorine-based polymers such as polyvinylidene fluoride, polytetrafluoroethylene, fluorinated polyvinylidene fluoride, and tetrafluoroethylene-ethylene copolymer. A single binder may be used, or two or more binders may be used in any ratio and combination. From the viewpoint of battery durability, styrene-butadiene rubber is preferred as the binder.

[0285] The binder content in the negative electrode active material layer is preferably 0.1 to 20% by mass. Here, from the viewpoint of battery durability, the above content is preferably 0.1% by mass or more, and more preferably 0.5% by mass or more. Furthermore, from the viewpoint of increasing the energy density of the battery, the above content is preferably 20% by mass or less, and more preferably 10% by mass or less.

[0286] When a rubbery polymer is used as the main component of the binder, the binder content in the negative electrode active material layer is preferably 0.1 to 5% by mass. Here, from the viewpoint of battery durability, the above content is preferably 0.1% by mass or more, and more preferably 0.5% by mass or more. Furthermore, from the viewpoint of increasing the energy density of the battery, the above content is preferably 5% by mass or less, and more preferably 2% by mass or less.

[0287] When a fluorine-based polymer is used as the main component of the binder, the binder content in the negative electrode active material layer is preferably 1 to 15% by mass. Here, from the viewpoint of battery durability, the above content is preferably 1% by mass or more, and more preferably 2% by mass or more. Furthermore, from the viewpoint of increasing the energy density of the battery, the above content is preferably 15% by mass or less, and more preferably 10% by mass or less.

[0288] Examples of conductive materials include vapor-grown carbon fiber (VGCF), carbon black such as acetylene black, carbonaceous materials such as graphite, carbon nanotubes and carbon nanofibers, and carbon-based materials such as amorphous carbon like needle coke. One conductive material may be used alone, or two or more may be used in any ratio and combination. Alternatively, instead of using a conductive agent, a carbon coating or an electronically conductive inorganic material coating may be applied to the surface of the negative electrode active material particles. From the viewpoint of enhancing conductivity, carbon black is preferred as the conductive material.

[0289] When the negative electrode active material layer contains a conductive material, the content of the conductive material in the negative electrode active material layer is preferably 0.01 to 20% by mass. Here, from the viewpoint of increasing conductivity, the above content is preferably 0.01% by mass or more, and more preferably 0.1% by mass or more. Furthermore, from the viewpoint of increasing the energy density of the battery, the above content is preferably 20% by mass or less, and more preferably 15% by mass or less.

[0290] Examples of thickening agents include carboxymethylcellulose, methylcellulose, hydroxymethylcellulose, ethylcellulose, polyvinyl alcohol, and their salts. A single thickening agent may be used, or two or more may be used in any ratio and combination. From the viewpoint of battery durability, carboxymethylcellulose is preferred as the thickening agent.

[0291] When the negative electrode active material layer contains a thickening agent, the content of the thickening agent in the negative electrode active material layer is preferably 0.1 to 5% by mass. Here, from the viewpoint of battery durability, the above content is preferably 0.1% by mass or more, and more preferably 0.5% by mass or more. Furthermore, from the viewpoint of increasing the energy density of the battery, the above content is preferably 5% by mass or less, and more preferably 2% by mass or less.

[0292] From the viewpoint of increasing the packing density of the negative electrode active material, it is preferable to compact the negative electrode active material layer using a hand press, roller press, or the like. The density of the negative electrode active material layer is 1.0 to 4.0 g / cm³. ３ This is preferable. Here, from the viewpoint of increasing the energy density of the battery, the above density is 1.0 g / cm³. ３ The above is preferable, 1.5 g / cm³ ３ The above is more preferable. Furthermore, from the viewpoint of impregnating with electrolyte, the density is 4.0 g / cm³. ３ The following are preferable.

[0293] The thickness of the negative electrode active material layer is preferably 10 to 500 μm. Here, from the viewpoint of increasing the energy density of the battery, the thickness is preferably 10 μm or more, and more preferably 15 μm or more. Also, from the viewpoint of improving the rate characteristics of the battery, the thickness is preferably 500 μm or less, and more preferably 300 μm or less. The negative electrode active material layer may be formed on one surface of the current collector, or on both surfaces of the current collector.

[0294] [3-3-2-2. Current Collector] Examples of materials for the current collector include metal materials such as aluminum, copper, nickel, stainless steel, and nickel-plated steel. Copper is preferred as the material for the current collector because it does not alloy with alkali metals and is inexpensive. Copper or aluminum is also preferred from the viewpoint of ease of processing and cost.

[0295] Examples of current collector shapes include metal foil, metal cylinder, metal coil, metal plate, metal thin film, expanded metal, punched metal, and foamed metal. From the viewpoint of improving the handling of the negative electrode, metal foil and metal thin film are preferred as current collector shapes. The metal thin film may be formed in a mesh shape.

[0296] When the shape of the current collector is plate-shaped or film-shaped, the thickness of the current collector is preferably 1 μm or more and 1 mm or less. Here, from the viewpoint of improving the handling of the negative electrode, the above thickness is preferably 1 μm or more, and more preferably 2 μm or more. Furthermore, from the viewpoint of increasing the energy density of the battery, the above thickness is preferably 1 mm or less, and more preferably 0.5 mm or less.

[0297] [3-3-3. Surface Coating of the Negative Electrode] The negative electrode may be one in which a substance with a different composition from the negative electrode active material (surface-adhered substance) is attached to the surface of the negative electrode. The surface-adhered substance on the surface of the negative electrode is described in the same way as the surface-adhered substance on the surface of the positive electrode in [3-2-3. Surface Coating of the Positive Electrode], and the preferred embodiments are also the same. In this specification, the surface-adhered substance attached to the surface of the negative electrode is also included in the negative electrode.

[0298] [3-4. Separator] In the battery according to this embodiment, it is preferable to interpose a separator between the positive electrode and the negative electrode to prevent short circuits. It is preferable to use a separator that is impregnated with an electrolyte.

[0299] The separator material can be any known material, as long as it does not significantly impair the effects of the present invention. The separator shape can be any known shape, as long as it does not significantly impair the effects of the present invention.

[0300] [3-5. Battery Design] [3-5-1. Electrode Group] The electrode group in this embodiment may be a stacked structure in which the positive electrode and the negative electrode are stacked with a separator in between, or a wound structure in which the positive electrode and the negative electrode are wound in a spiral shape with a separator in between.

[0301] The electrode group occupancy rate, that is, the volume ratio of the electrode group to the total internal volume of the battery, is preferably 40 to 90%. Here, from the viewpoint of increasing the energy density of the battery, the electrode group occupancy rate is preferably 40% or more, and more preferably 50% or more. Furthermore, from the viewpoint of impregnation with electrolyte, the electrode group occupancy rate is preferably 90% or less, and more preferably 80% or less.

[0302] [3-5-2. Current Collection Structure] In this embodiment, when the electrode group has a laminated structure, a structure formed by bundling the metal core portions of each electrode layer and welding them to a terminal, or a structure that reduces resistance by providing multiple terminals within the electrode, is preferably used. Furthermore, when the electrode group has a wound structure, a structure that reduces resistance by providing multiple lead structures on each electrode and bundling them to a terminal is preferably used.

[0303] [3-5-3. Protective Elements] Examples of protective elements include PTC (Positive Temperature Coefficient) elements whose resistance increases with heat generation due to excessive current, thermal fuses, thermistors, and current interruption valves that interrupt the current flowing through the circuit due to a rapid rise in internal pressure or temperature of the battery during abnormal heat generation. One type of protective element may be used alone, or two or more types may be used in any ratio and combination. From the viewpoint of battery safety, protective elements that do not operate under normal high-current use are preferred, but it is even more preferable to design the battery so that abnormal heat generation or thermal runaway does not occur even without protective elements.

[0304] [3-5-4. Outer casing] The battery according to this embodiment is typically constructed by housing the positive electrode, negative electrode, separator, and electrolyte inside an outer casing.

[0305] Examples of materials for the exterior include metals such as iron, aluminum, and aluminum alloys; and laminated films. From the viewpoint of weight reduction and cost, metals and laminated films are preferred for the exterior material, and from the viewpoint of pressure resistance for operating the current interruption valve, iron is more preferred.

[0306] When metal is used as the material for the exterior, the structure of the exterior may be a sealed structure formed by welding metals together using laser welding, resistance welding, or ultrasonic welding, or it may be a crimped structure using metal via a resin gasket.

[0307] Examples of exterior shapes include cylindrical, rectangular, laminated, coin-shaped, and large. From the viewpoint of increasing the energy density of the battery, cylindrical, rectangular, and laminated exteriors are preferred.

[0308] [3-6. Method for Manufacturing a Battery] The method for manufacturing a battery according to the first aspect of this embodiment includes the steps of housing a positive electrode and a negative electrode containing niobium in an outer casing, and injecting an electrolyte material / composition containing an anion-containing compound having S=O bonds and S-F bonds, or a composition containing an anion-containing compound having S=O bonds and S-F bonds, into the outer casing. The anion-containing compound is preferably an anion-containing compound having S=O bonds and S-F bonds and having fluorosulfonic acid anion as a constituent component.

[0309] A method for manufacturing a battery according to a second aspect of this embodiment includes the steps of housing a positive electrode and a negative electrode containing an element of niobium in an outer casing, and injecting an electrolyte containing a compound having an Si-F bond or a composition containing a compound having an Si-F bond into the outer casing.

[0310] A method for manufacturing a battery according to a third aspect of this embodiment includes the steps of housing a positive electrode and a negative electrode containing niobium in an outer casing, and injecting an electrolyte containing a compound represented by general formula (3) or a composition containing a compound represented by general formula (3) into the outer casing.

[0311] The same description as for the electrolyte described above in [2. Electrolyte] applies to the electrolyte, and the preferred embodiments are also the same. Other electrolytes may be used in combination, as long as they do not significantly impair the effects of the present invention.

[0312] The positive electrode in the battery manufacturing method is described in the same way as the positive electrode of the battery described above in [3-2. Positive Electrode], and the preferred embodiment is also the same.

[0313] The negative electrode in the battery manufacturing method is described in the same way as the negative electrode of the battery described above in [3-3. Negative Electrode], and the preferred embodiment is also the same.

[0314] The same description as for the battery casing in the method of manufacturing the battery applies to the casing of the battery described above in [3-5-4. Casing], and the preferred embodiments are also the same.

[0315] The steps of housing the positive and negative electrodes in the outer casing and injecting the electrolyte into the outer casing can be performed in any order, but from the viewpoint of impregnating the electrodes with the electrolyte, it is preferable to perform the step of injecting the electrolyte into the outer casing after the step of housing the positive and negative electrodes in the outer casing.

[0316] In the process of housing the positive electrode and negative electrode in an outer casing, it is preferable to house the separator together with the positive electrode and negative electrode in the outer casing from the viewpoint of simplifying the manufacturing process and improving productivity.

[0317] [3-7. Applications] From the viewpoint of being able to be used repeatedly for a variety of applications, the battery according to this embodiment is preferably a non-aqueous electrolyte secondary battery, more preferably an alkaline ion secondary battery, and even more preferably a lithium ion secondary battery.

[0318] The battery according to this embodiment can be used for various known applications. Specific examples of applications include, for example, laptop computers, pen-input computers, mobile computers, e-book players, mobile phones, portable fax machines, portable copiers, portable printers, portable audio players, mini video cameras, headphone stereos, video camcorders, LCD televisions, handheld vacuum cleaners, portable CDs, MiniDiscs, transceivers, electronic organizers, calculators, memory cards, portable tape recorders, radios, backup power supplies, motors, automobiles, motorcycles, mopeds, bicycles, airplanes, helicopters, airships, gliders and other aircraft, drones, amphibious vehicles, lighting fixtures, toys, game consoles, clocks, power tools, strobes, cameras, household backup power supplies, business backup power supplies, load leveling power supplies, and renewable energy storage power supplies.

[0319] In particular, the battery according to this embodiment has excellent capacity during rapid charging, making it suitable for use in vehicles such as automobiles, motorcycles, mopeds, and bicycles, and especially suitable for use in automobiles. That is, the present invention also relates to vehicles including the above-mentioned battery.

[0320] One aspect of this embodiment is as follows: [1]' An anion-containing compound having an S=O bond and an S-F bond, used in a battery having a negative electrode containing a niobium element. [2]' The anion-containing compound according to [1]', wherein the anion-containing compound having an S=O bond and an S-F bond comprises a fluorosulfonic acid anion as a component. [3]' The anion-containing compound according to [1]' or [2]', wherein the anion-containing compound having an S=O bond and an S-F bond comprises a fluorosulfonylimide anion. [4]' A composition comprising the anion-containing compound according to any one of [1]' to [3]'. [5]' A method for using the anion-containing compound according to any one of [1]' to [3]' or the composition according to [4]' in a battery having a negative electrode containing a niobium element. [6]' An electrolyte comprising the anion-containing compound described in any one of [1]' to [3]' or the composition described in [4]', an electrolyte, and a non-aqueous solvent, for use in a battery having a negative electrode containing niobium. [7]' The electrolyte according to [6]', wherein the ratio (x / n) (mass% / unit) of the content x mass% of the anion-containing compound having S=O bonds and S-F bonds in the electrolyte to the number n of S=O bonds in one molecule of the anion-containing compound having S=O bonds and S-F bonds is 3.0 or less. [8]' A method for using an electrolyte comprising the anion-containing compound described in any one of [1]' to [3]' or the composition described in [4]', an electrolyte, and a non-aqueous solvent in a battery having a negative electrode containing niobium. [9]' A method for producing an electrolyte used in a battery having a negative electrode containing niobium, comprising the steps of dissolving an anion-containing compound according to any one of [1]' to [3]' or the composition according to [4]' and an electrolyte in a non-aqueous solvent.

[10] ' A battery comprising a positive electrode, a negative electrode containing niobium, and the electrolyte according to [6]' or [7]'.

[11] ' A method for producing a battery, comprising the steps of housing the positive electrode and the negative electrode containing niobium in an outer casing, and injecting the electrolyte according to [6]' or [7]' into the outer casing.

[12] ' A vehicle comprising the battery according to

[10] '.

[0321] Another aspect of this embodiment is as follows: [1]'' A compound having an Si-F bond, used in a battery having a negative electrode containing an element of niobium. [2]'' The compound according to [1]'', wherein the compound having an Si-F bond is a compound represented by the following general formula (1).

[0322]

[0323] (In general formula (1), R １ ~R ３ Each of these independently represents a fluorine atom, a hydrocarbon group which may be substituted with a halogen atom, or a hydrocarbon group which has a polar group.

[0324] [3]'' R in the general formula (1) １ R is a hydrocarbon group which may be substituted with a halogen atom, ３ The compound according to [2]'' wherein R is a hydrocarbon group or a fluorine atom which may be substituted with a halogen atom. [4]'' In the general formula (1) R １ and R ３ The compound according to [2]'' or [3]'' wherein R is a methyl group. [5]'' In the general formula (1) above, R ２ The compound according to any one of [2]'' to [4]'', wherein the hydrocarbon group having four or more carbon atoms may be substituted with a halogen atom, or the hydrocarbon group having a polar group. [6]'' A composition comprising the compound according to any one of [1]'' to [5]''.

[0325] [7]'' A method for using the compound described in any one of [1]'' to [5]'' or the composition described in [6]'' in a battery having a negative electrode containing an element of niobium.

[0326] [8]'' An electrolyte comprising the compound described in any one of [1]'' to [5]'' or the composition described in [6]'', an electrolyte, and a non-aqueous solvent, for use in a battery having a negative electrode containing niobium. [9]'' A method for using an electrolyte comprising the compound described in any one of [1]'' to [5]'' or the composition described in [6]'', an electrolyte, and a non-aqueous solvent in a battery having a negative electrode containing niobium.

[10] '' A method for producing an electrolyte for use in a battery having a negative electrode containing niobium, comprising the step of dissolving the compound described in any one of [1]'' to [5]'' or the composition described in [6]'' and the electrolyte in a non-aqueous solvent.

[11] '' A battery comprising a positive electrode, a negative electrode containing niobium, and the electrolyte described in [8]''.

[12] '' A method for producing a battery, comprising the step of housing the positive electrode and the negative electrode containing niobium in an outer casing, and the step of injecting the electrolyte described in [8]'' into the outer casing.

[13] '' A vehicle comprising the battery described in

[11] ''.

[0327] The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to these examples.

[0328] In the first test example A, the compounds used in this example and comparative example are as follows: [Electrolyte] - Anion-containing compound having S=O bond and S-F bond Compound 1A: Lithium fluorosulfonate (FSO ３ Li has 2 S=O bonds in one molecule. • Electrolyte LiPF ６ Non-aqueous solvents: ethylene carbonate (EC), ethyl methyl carbonate (EMC), dimethyl carbonate (DMC)

[0329] In the second test example B, the compounds used in this example and the comparative example are as follows: [Electrolyte] Compound 1B having a Si-F bond: 3-(fluorodimethylsilyl)propylmethyl carbonate

[0330]

[0331] Compound 2B: 3-(difluoromethylsilyl)propylmethyl carbonate

[0332]

[0333] Compound 3B: 3-(trifluorosilyl)propylmethyl carbonate

[0334]

[0335] Compound 4B: Fluorodimethyloctylsilane

[0336]

[0337] Compound 5B: Cyclohexyldifluoromethylsilane

[0338]

[0339] ・Electrolyte LiPF ６ Non-aqueous solvents: ethylene carbonate (EC), ethyl methyl carbonate (EMC), dimethyl carbonate (DMC)

[0340] [Synthesis of Compounds Containing Si-F Bonds] Compounds 1B to 5B were synthesized according to the following synthesis examples. In each synthesis example, a 2 wt% xylene solution of Sigma-Aldrich platinum(0)-1,3-divinyltetramethyldisiloxane complex was used as the Karstedt catalyst. The various analytical methods used in the following synthesis examples are as follows.

[0341] [Nuclear magnetic resonance (NMR) analysis] １ H, １３ C, １９ F-NMR measurements were performed using a Bruker 400 UltraShield at 400, 101, and 376 MHz, respectively. The samples were treated with deuterated chloroform (CDCl). ３ It was dissolved in () and measured.

[0342] [Gas Chromatography (GC) Analysis] 100 μL of the sample was dissolved in 1 mL of hexane. The resulting solution was analyzed using a GC analyzer (Shimadzu GC-2010). The conditions were as follows: Column: DB-1 (length 30 m, inner diameter 0.32 mm, film thickness 0.25 μm, Agilent Technologies) Detector: FID Temperature: 40°C → 280°C, increased at 10°C / min. Purity was determined from the peak area %.

[0343] <Synthesis Example 1B: Synthesis of Compound 1B (3-(fluorodimethylsilyl)propylmethyl carbonate)> Allyl methyl carbonate (2.00 g, 17.2 mmol) was dissolved in toluene (20 mL), and 20 μL of Karstedt's catalyst was added. Chlorodimethylsilane (2.25 mL, 20.7 mmol) was added dropwise while stirring under ice cooling. A toluene solution of 3-(chlorodimethylsilyl)propylmethyl carbonate was obtained by heating and stirring at 70°C for 15 minutes. In another reactor, potassium fluoride (2.00 g, 34.5 mmol), 18-crown-6-ether (0.911 g, 3.44 mmol) and acetonitrile (40 mL) were charged, and the toluene solution of 3-(chlorodimethylsilyl)propylmethyl carbonate was added dropwise while stirring under ice cooling, and the mixture was heated under reflux for 3 hours. The reaction mixture was filtered, concentrated with solvent, and then 3-(fluorodimethylsilyl)propylmethyl carbonate (0.185 g, 0.952 mmol) was obtained by silica gel column chromatography. The purity estimated by GC analysis was 99%. １ H-NMR, １３ C-NMR, １９ The F-NMR analysis results were as follows: １ H-NMR (400MHz, CDCl ３ ): δ = 4.12 (t, J = 6.8Hz, 2H), 3.78 (s, 3H), 1.80-1.73 (m, 2H), 0.75-0.69 (m, 2H), 0.24 (s, 6H) １３ C-NMR (101MHz, CDCl ３ ): δ=155.8, 70.0, 54.7, 22.0, 12.4, -1.6 １９ F-NMR (376MHz, CDCl ３ ): δ = -162.2

[0344] <Synthesis Example 2B: Synthesis of Compound 2B (3-(difluoromethylsilyl)propylmethyl carbonate)> Allyl methyl carbonate (6.50 g, 56.0 mmol) was dissolved in toluene (65 mL), and 70 μL of Karstedt's catalyst was added. Dichloromethylsilane (6.90 mL, 67.2 mmol) was added dropwise while stirring under ice cooling. A toluene solution of 3-(dichloromethylsilyl)propylmethyl carbonate was obtained by heating and stirring at 80°C for 15 minutes. In another reactor, potassium fluoride (13.0 g, 224 mmol), 18-crown-6-ether (2.96 g, 11.2 mmol) and acetonitrile (130 mL) were charged, and the toluene solution of 3-(dichloromethylsilyl)propylmethyl carbonate was added dropwise while stirring under ice cooling. After heating under reflux for 3 hours, it was allowed to cool to room temperature. The reaction mixture was filtered, the solvent was removed by distillation, and then 3-(difluoromethylsilyl)propylmethyl carbonate (80.0 mg, 0.404 mmol) was obtained by distillation. The purity estimated by GC analysis was 99%. １ H-NMR, １９ The F-NMR analysis results were as follows: １ H-NMR (400MHz, CDCl ３ ): δ = 4.13 (t, J = 6.5Hz, 2H), 3.79 (s, 3H), 1.87-1.79 (m, 2H), 0.89-0.82 (m, 2H), 0.38-0.35 (m, 3H) １９ F-NMR (376MHz, CDCl ３ ): δ = -135.5

[0345] <Synthesis Example 3B: Synthesis of Compound 3B (3-(trifluorosilyl)propylmethyl carbonate)> Allyl methyl carbonate (7.50 g, 64.6 mmol) was dissolved in toluene (110 mL), and 75 μL of Karstedt's catalyst was added. Trimethoxysilane (9.87 mL, 77.5 mmol) was added dropwise while stirring under ice cooling. The mixture was heated and stirred at 50°C for 15 minutes. By distillation of the solvent, 3-(trimethoxysilyl)propylmethyl carbonate (12.3 g, 51.5 mmol) was obtained. 3-(trimethoxysilyl)propylmethyl carbonate (12.3 g, 51.5 mmol) was dissolved in diethyl ether (180 mL), and boron trifluoride diethyl ether complex (6.46 mL, 51.5 mmol) was added dropwise under ice cooling. After heating under reflux for 6 hours, the low-boiling by-products and solvent were removed by distillation. Purification using a Kugellohr distillation apparatus yielded 3-(trifluorosilyl)propylmethyl carbonate (1.26 g, 6.23 mmol). The purity estimated by GC analysis was 97%. １ H-NMR, １３ C-NMR, １９ The F-NMR analysis results were as follows: １ H-NMR (400MHz, CDCl ３ ): δ = 4.17 (t, J = 6.3Hz, 2H), 3.80 (s, 3H), 1.96-1.89 (m, 2H), 1.12-1.07 (m, 2H) １３ C-NMR (101MHz, CDCl ３ ): δ=155.8, 68.6, 55.0, 20.6, 3.4 １９ F-NMR (376MHz, CDCl ３ ): δ = -137.1

[0346] <Synthesis Example 4B: Synthesis of Compound 4B (Fluorodimethyloctylsilane)> Methoxydimethyloctylsilane (5.00 g, 24.7 mmol) was added to a reactor, and boron trifluoride ether complex (1.05 mL, 8.40 mmol) was added under ice cooling. The mixture was stirred at 55°C for 1 hour. After removing the low-boiling components by distillation, fluorodimethyloctylsilane (4.06 g, 21.3 mmol) was obtained by distillation. The purity estimated by GC analysis was 99%.１ H-NMR, １３ C-NMR, １９ The F-NMR analysis results were as follows: １ H-NMR (400MHz, CDCl ３ ): 1.38-1.27 (m, 12H), 0.88 (t, J = 6.9Hz, 3H), 0.70-0.64 (m, 2H), 0.20 (d, J Ｈ－Ｆ =7.5Hz, 6H) １３ C-NMR (101MHz, CDCl ３ ): 33.1, 31.9, 29.3, 29.2, 22.7, 22.6, 16.5, 14.1, -1.4 １９ F-NMR (376MHz, CDCl ３ ): -162.2

[0347] <Synthesis Example 5B: Synthesis of Compound 5B (Cyclohexyldifluoromethylsilane)> Cyclohexyldimethoxymethylsilane (5.00 g, 26.5 mmol) was added to a reactor, and boron trifluoride ether complex (2.33 mL, 17.8 mmol) was added under ice cooling. The mixture was stirred at room temperature for 2 hours and then at 45°C for 5 hours. After removing the low-boiling components by distillation, cyclohexyldifluoromethylsilane (2.35 g, 14.3 mmol) was obtained by distillation. The purity estimated by GC analysis was 99%. １ H-NMR, １３ C-NMR, and １９ The F-NMR analysis results were as follows: １ H-NMR (400MHz, CDCl ３ ): 1.80-1.71 (m, 5H), 1.35-1.24 (m, 5H), 0.96-0.90 (m, 1H), 0.29 (t, J Ｈ－Ｆ =6.5Hz, 3H) １３ C-NMR (101MHz, CDCl ３ ): 27.1, 26.4, 25.2, 24.2, -6.2 １９ F-NMR (376MHz, CDCl ３ ): -141.7

[0348] In the third test example C, the compounds used in this example and the comparative example are as follows: [Electrolyte] Compound 1C: Compound represented by general formula (3) Compound represented by the following formula

[0349]

[0350] Compound 2C: The compound represented by the following formula

[0351]

[0352] ・Electrolyte LiPF ６ Non-aqueous solvents: ethylene carbonate (EC), ethyl methyl carbonate (EMC), dimethyl carbonate (DMC)

[0353] [Manufacturing of the positive electrode] Lithium transition metal composite oxide (LiNi) is used as the positive electrode active material. ０．５ Co ０．２ Mn ０．３ O ２ 90 parts by mass of ), 3 parts by mass of polyvinylidene fluoride as a binder, and 7 parts by mass of acetylene black as a conductive material were mixed in N-methylpyrrolidone using a disperser to obtain a slurry. The obtained slurry was applied to both sides of a current collector (aluminum foil with a thickness of 15 μm), dried, and the density was 3.0 g / cm³. ３ The material was pressed in this manner to obtain a positive electrode with a positive electrode active material layer formed on top.

[0354] [Manufacturing of negative electrode 1: Nb ２ O ５ [Negative electrode] Nb as negative electrode active material ２ O ５ A slurry was obtained by mixing 91 parts by mass of powder, 7 parts by mass of acetylene black as a conductive material, 1 part by mass (based on solid content) of aqueous styrene-butadiene rubber dispersion (styrene-butadiene rubber concentration 50% by mass) as a binder, and 1 part by mass (based on solid content) of aqueous carboxymethylcellulose sodium dispersion (carboxymethylcellulose sodium concentration 1% by mass) as a thickener using a disperser. The obtained slurry was applied to one side of a current collector (20 μm thick copper foil) and dried (density 1.0 g / cm³). ３ ), a negative electrode with a negative electrode active material layer formed was obtained.

[0355] [Manufacturing of negative electrode 2: LTO negative electrode] Li as the negative electrode active material ４ Ti ５ O １２ 95 parts by mass of (LTO) powder, 2 parts by mass of carbon black as a conductive material, and 3 parts by mass of polyvinylidene fluoride as a binder were mixed in N-methylpyrrolidone using a disperser to obtain a slurry. The obtained slurry was applied to one side of a current collector (aluminum foil with a thickness of 20 μm), dried, and a density of 1.9 g / cm³ was obtained. ３ The material was pressed in such a manner to obtain a negative electrode with a negative electrode active material layer formed on top.

[0356] [Manufacturing of Negative Electrode 3: TNO Negative Electrode] TiNb as the negative electrode active material ２ O ７ 91 parts by mass of (TNO) powder, 7 parts by mass of carbon black as a conductive material, 1 part by mass (based on solid content) of aqueous styrene-butadiene rubber dispersion (styrene-butadiene rubber concentration 50% by mass) as a binder, and 1 part by mass (based on solid content) of aqueous carboxymethylcellulose sodium dispersion (carboxymethylcellulose sodium concentration 1% by mass) as a thickener were mixed in N-methylpyrrolidone using a disperser to obtain a slurry. The obtained slurry was applied to one side of a current collector (20 μm thick copper foil), dried, and a density of 2.0 g / cm³ was obtained. ３ The material was pressed in such a manner to obtain a negative electrode with a negative electrode active material layer formed on top.

[0357] [Electrolyte Preparation A] - Examples 1A to 6A, Comparative Example 3A Under a dry argon atmosphere, a mixture of ethylene carbonate (EC), ethyl methyl carbonate (EMC), and dimethyl carbonate (DMC) (volume ratio EC:EMC:DMC = 3:4:3) was mixed with thoroughly dried LiPF as the electrolyte. ６ The base electrolyte was prepared by dissolving the compound to a concentration of 1 mol / L. Compound 1A was added to the base electrolyte so that its content (x mass%) in 100% by mass of the final electrolyte was as shown in Tables 1 and 2.

[0358] Examples 7A-8A LiPO4 was added to the base electrolyte prepared in the same manner as in Example 1A.２ F ２ The electrolyte was prepared by adding the ingredients in the proportions shown in Table 2.

[0359] [Electrolyte Preparation A] Comparative Examples 1A, 2A, and 4A: Compound 1A was not added to the base electrolyte prepared in the same manner as in Example 1A, and the base electrolyte was used as is.

[0360] Comparative Example 5A: Ethylene sulfite (ES) was added to the base electrolyte prepared in the same manner as in Example 1A, in the proportions shown in Table 2, to prepare the electrolyte.

[0361] [Battery Manufacturing A] - Example 1A, Example 2A, Comparative Example 1A The obtained positive electrode and the obtained negative electrode 1 (Nb ２ O ５ An electrode group was obtained by laminating the positive and negative electrodes (and the negative electrode) with a polypropylene separator in between. The obtained electrode group was inserted into a laminate film bag made of aluminum (40 μm thick) with both sides coated with a resin layer, so that the terminals of the positive and negative electrodes protruded from the bag. The obtained electrolyte was then injected into the bag, vacuum sealed, and a pouch-type battery was manufactured.

[0362] [Battery Manufacturing A] Comparative Example 2A, Comparative Example 3A Negative electrode 1 (Nb ２ O ５ A pouch-type battery was manufactured in the same manner as in Example 1A, except that a negative electrode 2 (LTO negative electrode) was used instead of the negative electrode.

[0363] [Battery Manufacturing A] - Examples 3A to 8A, Comparative Examples 4A to 5A Negative electrode 1 (Nb ２ O ５ A pouch-type battery was manufactured in the same manner as in Example 1A, except that negative electrode 3 (TNO negative electrode) was used instead of the negative electrode.

[0364] [Pre-test charge / discharge A] - Examples 1A, 2A, Comparative Examples 1A-3A In a constant temperature bath at 25°C, the batteries prepared above were charged to 3.1V using constant current-constant voltage (CC-CV charging) with a current equivalent to 0.1C (1C refers to the current value that takes 1 hour to charge or discharge; the same applies hereinafter), and then discharged to 1.6V using CC at 0.1C. This was repeated twice to perform initial conditioning.

[0365] [Pre-test charge / discharge A] Examples 3A to 8A, Comparative Examples 4A to 5A In a constant temperature bath at 25°C, the batteries prepared above were charged to 3.0V using constant current-constant voltage (CC-CV charging) with a current equivalent to 0.2C (1C refers to the current value that takes 1 hour to charge or discharge; the same applies hereinafter), and then discharged to 1.5V using CC at 0.2C. This was repeated twice to perform initial conditioning.

[0366] [Rapid Charging Test A] ・Examples 1A, 2A, and Comparative Examples 1A-3A: Batteries were initially conditioned in a constant temperature bath at 25°C and then CC-CV charged to 2.4V at 0.2C. After discharging to 1.6V at 0.2C, they were CC-charged to 3.1V at 3.0C. The charging capacity per gram of negative electrode active material (mAh / g) at this time was defined as the 3C charging capacity. The 3C charging capacities of Examples 1A-2A and Comparative Examples 1A-3A were determined using the 3C charging capacity of Comparative Example 1A as a baseline of 100.0.

[0367] [Rapid Charging Test A] ・Examples 3A to 8A, Comparative Examples 4A to 5A Batteries were initially conditioned in a constant temperature bath at 25°C and then CC-CV charged to 2.2V at 0.2C. After discharging to 1.5V at 0.2C, they were CC-charged to 3.0V at 3.0C. The charging capacity per gram of negative electrode active material (mAh / g) at this time was defined as the 3C charging capacity. The 3C charging capacities of Examples 3A to 8A and Comparative Examples 4A to 5A were determined using the 3C charging capacity of Comparative Example 4A as a baseline of 100.0.

[0368] Tables 1 and 2 show the ratio (x / n) of the content (x mass%) of the anion-containing compound having S=O and S-F bonds in 100 mass% of the electrolyte, to the number of S=O bonds (n) in one molecule of the anion-containing compound having S=O and S-F bonds, and the evaluation results of the normalized 3C charging capacity for each example.

[0369]

[0370]

[0371] As can be seen from Tables 1 and 2, Examples 1A to 8A, which used anion-containing compounds having S=O and S-F bonds and fluorosulfonic acid anions as a component in batteries with a niobium-containing negative electrode, all exhibited superior 3C charging capacity compared to Comparative Examples 1A, 2A, and 4A, which did not contain anion-containing compounds having S=O and S-F bonds, and Comparative Example 5A, which had ES added. Furthermore, although Examples 1A to 8A used an electrolyte with the same compound 1A added, they showed superior 3C charging capacity compared to Comparative Example 3A, which used an LTO negative electrode instead of a niobium-containing negative electrode. Moreover, when compounds 1A and 2A were used as anion-containing compounds having S=O and S-F bonds and fluorosulfonic acid anions as a component, using an LTO negative electrode did not only fail to improve 3C charging capacity, but actually resulted in a decrease in capacity. In contrast, it was found that applying the compounds according to this embodiment to batteries with a niobium-containing negative electrode produced a remarkable effect.

[0372] The results from Examples 1A, 4A, 5A, and 6A, which used compound 1A, showed that setting the x / n ratio to 3.0 or less resulted in a significant improvement in the 3C charging capacity during rapid charging.

[0373] [Electrolyte Preparation B] - Example 1B, Comparative Example 2B Under a dry argon atmosphere, a mixture of ethylene carbonate (EC), ethyl methyl carbonate (EMC), and dimethyl carbonate (DMC) (volume ratio EC:EMC:DMC = 3:4:3) was mixed with thoroughly dried LiPF as the electrolyte. ６ The base electrolyte was prepared by dissolving the compound to a concentration of 1 mol / L. Compound 1B was added to the base electrolyte so that its content (x mass%) in the final 100% by mass of the electrolyte was as shown in Table 3, and the electrolyte was prepared.

[0374] [Electrolyte Preparation B] - Example 2B, Comparative Example 3B Compound 2B was added to a base electrolyte prepared in the same manner as in Example 1B, such that the content (x mass%) in the final 100% by mass of the electrolyte was as shown in Table 3, and the electrolyte was prepared.

[0375] [Electrolyte Preparation B] Example 3B Compound 3B was added to a base electrolyte prepared in the same manner as in Example 1B, such that the content (x mass%) in the final 100% by mass of the electrolyte was as shown in Table 3, and the electrolyte was prepared.

[0376] [Electrolyte Preparation B] - Example 4B, Comparative Example 4B Compound 4B was added to a base electrolyte prepared in the same manner as in Example 1B, such that the content (x mass%) in the final 100% by mass of the electrolyte was as shown in Table 3, and the electrolyte was prepared.

[0377] [Electrolyte Preparation B] - Example 5B, Comparative Example 5B Compound 5B was added to a base electrolyte prepared in the same manner as in Example 1B, such that the content (x mass%) in the final 100% by mass of the electrolyte was as shown in Table 3, and the electrolyte was prepared.

[0378] [Electrolyte Preparation B] Comparative Example 1B, Comparative Example 6B None of Compounds 1B to 5B were added to the base electrolyte prepared in the same manner as in Example 1B, and the base electrolyte was used as is.

[0379] [Battery Manufacturing B] - Examples 1B to 5B, Comparative Example 1B Obtained positive electrode and obtained negative electrode 1 (Nb ２ O ５ An electrode group was obtained by laminating the positive and negative electrodes (and the negative electrode) with a polypropylene separator in between. The obtained electrode group was inserted into a laminate film bag made of aluminum (40 μm thick) with both sides coated with a resin layer, so that the terminals of the positive and negative electrodes protruded from the bag. The obtained electrolyte was then injected into the bag, vacuum sealed, and a pouch-type battery was manufactured.

[0380] [Battery Manufacturing B] Comparative Examples 2B to 6B Negative electrode 1 (Nb ２ O ５ A pouch-type battery was manufactured in the same manner as in Example 1B, except that a negative electrode 2 (LTO negative electrode) was used instead of the negative electrode.

[0381] [Pre-test charge / discharge B] The battery prepared above was charged to 3.1V using constant current-constant voltage (CC-CV) charging with a current equivalent to 0.1C (1C refers to the current value that takes 1 hour to charge or discharge; the same applies hereinafter) in a constant temperature bath at 25°C, and then discharged to 1.6V using CC at 0.1C. This was repeated twice to perform initial conditioning.

[0382] [Discharge Rate Test B] After initial conditioning in a constant temperature bath at 25°C, the battery was CC-CV charged to 2.4V at 0.2C. Then, it was CC-CV charged to 3.1V at 0.2C, and then discharged to 1.6V at 3.0C. The discharge capacity per gram of negative electrode active material (mAh / g) at this time was defined as the 3C discharge capacity. The 3C discharge capacity of each example and comparative example was determined using the 3C discharge capacity of Comparative Example 1B as a reference of 100.0. The results are shown in Table 3.

[0383] [Charging Rate Test B] After initial conditioning in a constant temperature bath at 25°C, the battery was CC-CV charged to 2.4V at 0.2C. After discharging to 1.6V at 0.2C, it was CC-charged to 3.1V at 3.0C. The charging capacity per gram of negative electrode active material (mAh / g) at this time was defined as the 3C charging capacity. The 3C charging capacity of each example and comparative example was determined using the 3C charging capacity of Comparative Example 1B as a reference (100.0). The results are shown in Table 3.

[0384]

[0385] As can be seen from Table 3, Examples 1B to 5B, which used compounds having Si-F bonds in batteries with a niobium-containing negative electrode, all showed superior 3C charging capacity and 3C discharging capacity compared to Comparative Examples 1B and 6B, which did not contain compounds having Si-F bonds. Furthermore, Example 1B, although using the same electrolyte with compound 1B added, showed significantly superior 3C charging capacity and 3C discharging capacity compared to Comparative Example 2B, which used an LTO negative electrode instead of a niobium-containing negative electrode. Similarly, Example 2B, using compound 2, showed superior 3C charging capacity and 3C discharging capacity compared to Comparative Example 3B, Example 4B, using compound 4B, showed superior 3C charging capacity and 3C discharging capacity compared to Comparative Example 3B, and Example 5B, using compound 5B, showed superior 3C charging capacity and 3C discharging capacity compared to Comparative Example 5B. Moreover, when compounds 1B and 4B were used as the compounds having Si-F bonds, using an LTO negative electrode did not only fail to improve 3C charging capacity and 3C discharging capacity, but actually tended to decrease the capacity. In contrast, it was found that applying the compound according to this embodiment to a battery having a negative electrode containing niobium element produced a remarkable effect.

[0386] Among Examples 1B to 5B, the compound having an Si-F bond is R in general formula (1). １ R is a hydrocarbon group which may be substituted with a halogen atom, ３ Examples 1B, 2B, 4B, and 5B, which use compounds 1B, 2B, 4B, and 5B respectively, in which R is a hydrocarbon group or fluorine atom that may be substituted with a halogen atom, exhibited particularly excellent 3C discharge capacity and 3C charge capacity. Among Examples 1B, 2B, 4B, and 5B, R in general formula (1) ２ Examples 4B and 5B, which use compounds 4B and 5B respectively, which are alkyl groups having 1 to 10 carbon atoms that may be substituted with halogen atoms, exhibit excellent 3C discharge capacity and R ２ Examples 1B and 2B, which use compounds 1B and 2B respectively, in which the hydrocarbon group has a polar group, exhibited excellent 3C discharge capacity.

[0387] [Electrolyte Preparation C] - Example 1C, Example 2C Under a dry argon atmosphere, a mixture of ethylene carbonate (EC), ethyl methyl carbonate (EMC), and dimethyl carbonate (DMC) (volume ratio EC:EMC:DMC = 3:4:3) was mixed with thoroughly dried LiPF as the electrolyte. ６ The compound was dissolved to a concentration of 1 mol / L to prepare the base electrolyte. Compound 1C was added to the base electrolyte so that its content (x mass%) in 100% by mass of the final electrolyte was as shown in Table 4 to prepare the electrolyte. [Electrolyte preparation C] Comparative example 1C The base electrolyte prepared in the same manner as in Example 1C was used as the electrolyte without adding either compound 1C or compound 2C.

[0388] [Battery Manufacturing C] - Example 1C, Example 2C, Comparative Example 1C The obtained positive electrode and the obtained negative electrode 3 (TNO negative electrode) were laminated with a polypropylene separator in between to obtain an electrode group. The obtained electrode group was inserted into a laminate film bag made of aluminum (thickness 40 μm) with both sides covered with a resin layer, so that the terminals of the positive and negative electrodes protruded from it. Then the obtained electrolyte was injected into the bag, vacuum sealed, and a pouch-type battery was manufactured.

[0389] [Pre-test charge / discharge C] The battery prepared above was charged to 3.0V using constant current-constant voltage (CC-CV) charging at a current equivalent to 0.2C (1C refers to the current value that takes 1 hour to charge or discharge; the same applies hereinafter) in a constant temperature bath at 25°C, and then discharged to 1.5V using CC at 0.2C. This was repeated twice to perform initial conditioning.

[0390] [Rapid Charging Test C] After initial conditioning in a constant temperature bath at 25°C, a battery was CC-CV charged to 2.2V at 0.2C. It was then discharged to 1.5V at 0.2C, and finally CC-charged to 3.0V at 3.0C. The charging capacity per gram of negative electrode active material (mAh / g) was defined as the 3C charging capacity. The 3C charging capacities of Example 1C, Example 2C, and Comparative Example 1C were determined, using the 3C charging capacity of Comparative Example 1A as a baseline of 100.0. The results are shown in Table 4.

[0391]

[0392] As can be seen from Table 4, both Example 1C and Example 2C, which used the compound represented by general formula (3) in a battery having a negative electrode containing niobium, showed superior 3C charging capacity compared to Comparative Example 1C, which did not contain the compound represented by general formula (3).

[0393] Although the present invention has been described in detail and with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention. This application is based on Japanese Patent Application No. 2024-166577 and Japanese Patent Application No. 2024-166578, both filed on September 25, 2024, which are incorporated herein by reference.

[0394] The battery according to this embodiment can be used in various known applications. Specific examples of applications include, for example, laptop computers, pen-input computers, mobile computers, e-book players, mobile phones, portable fax machines, portable copiers, portable printers, portable audio players, small video cameras, headphone stereos, video camcorders, LCD televisions, handheld vacuum cleaners, portable CDs, MiniDiscs, transceivers, electronic organizers, calculators, memory cards, portable tape recorders, radios, backup power supplies, motors, automobiles, motorcycles, mopeds, bicycles, airplanes, helicopters, airships, gliders and other aircraft, drones, amphibious vehicles, lighting fixtures, toys, game consoles, clocks, power tools, strobes, cameras, household backup power supplies, business backup power supplies, load leveling power supplies, and renewable energy storage power supplies. The above battery is particularly excellent in improving capacity during rapid charging, and can therefore be suitably used in vehicles such as automobiles, motorcycles, mopeds, and bicycles, and is especially suitable for use in automobiles.

Claims

1. An anion-containing compound having an S=O bond and an S-F bond, and comprising a fluorosulfonate anion as a component, for use in a battery having a negative electrode containing niobium.

2. A composition comprising the anion-containing compound described in claim 1.

3. Use of the anion-containing compound according to claim 1 or the composition according to claim 2 in a battery having a negative electrode containing a niobium element.

4. A method for using the anion-containing compound described in claim 1 or the composition described in claim 2 in a battery having a negative electrode containing a niobium element.

5. An electrolyte comprising the anion-containing compound described in claim 1 or the composition described in claim 2, an electrolyte, and a non-aqueous solvent, used in a battery having a negative electrode containing an element of niobium.

6. The electrolyte according to claim 5, wherein the ratio (x / n) (mass% / unit) of the content x mass% of the anion-containing compound having S=O bonds and S-F bonds and comprising fluorosulfonic acid anions as components in the electrolyte to the number n of S=O bonds in one molecule of the anion-containing compound having S=O bonds and S-F bonds and comprising fluorosulfonic acid anions as components in the electrolyte is 3.0 or less.

7. A method for producing an electrolyte for use in a battery having a negative electrode containing a niobium element, comprising the steps of dissolving the anion-containing compound according to claim 1 or the composition according to claim 2, and the electrolyte in a non-aqueous solvent.

8. A battery comprising a positive electrode, a negative electrode containing niobium, and the electrolyte according to claim 5.

9. A method for manufacturing a battery, comprising the steps of housing a positive electrode and a negative electrode containing niobium in an outer casing, and injecting the electrolyte described in claim 5 into the outer casing.

10. A vehicle comprising the battery described in claim 8.

11. A compound having an Si-F bond, which is used in a battery having a negative electrode containing niobium.

12. The compound according to claim 11, wherein the compound having the Si-F bond is a compound represented by the following general formula (1). (In general formula (1), R １ ~R ３ Each of these independently represents a fluorine atom, a hydrocarbon group which may be substituted with a halogen atom, or a hydrocarbon group which has a polar group.

13. A composition comprising the compound described in claim 11.

14. Use of the compound according to claim 11 or 12, or the composition according to claim 13, in a battery having a negative electrode containing a niobium element.

15. A method for using the compound according to claim 11 or 12, or the composition according to claim 13, in a battery having a negative electrode containing an element of niobium.

16. A compound represented by the following general formula (3), which is used in a battery having a negative electrode containing niobium. (In general formula (3), R represents a hydrocarbon group which may be substituted with a halogen atom, or a hydrocarbon group which has a polar group.) 17. A composition comprising the compound described in claim 16.

18. Use of the compound according to claim 16 or the composition according to claim 17 in a battery having a negative electrode containing an element of niobium.

19. A method for using the compound described in claim 16 or the composition described in claim 17 in a battery having a negative electrode containing an element of niobium.

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