Nonaqueous electrolyte solution for batteries, lithium secondary battery precursor, method for producing lithium secondary battery, and lithium secondary battery

Abstract

A nonaqueous electrolyte solution for batteries, which contains an additive A that is a compound (I) and a specific additive B, and wherein the content of the additive A is more than 0.01 mass% and less than 0.5 mass% with respect to the total amount of the nonaqueous electrolyte solution for batteries. R11 each independently represents a fluoro group (-F), a hydrocarbon group having 1-8 carbon atoms which may contain a fluoro group (-F) as a substituent, or a fluorocarbon group having 1-8 carbon atoms, and h represents an integer of 0-4. # imgabs0 #

Description

Technical Field

[0001] The present disclosure relates to a non-aqueous electrolyte for a battery, a lithium secondary battery precursor, a method for producing a lithium secondary battery, and a lithium secondary battery. Background Art

[0002] In recent years, various studies have been conducted on nonaqueous electrolyte solutions used in batteries such as lithium secondary batteries.

[0003] For example, Patent Documents 1 to 6 disclose non-aqueous electrolyte solutions containing 1,3-propene sultone as an additive.

[0004] Patent Document 1: Japanese Patent Application Publication No. 2002-329528

[0005] Patent Document 2: Japanese Patent Application Publication No. 2008-198542

[0006] Patent Document 3: Japanese Patent Application Publication No. 2010-92698

[0007] Patent Document 4: Japanese Patent Application Publication No. 2014-27196

[0008] Patent Document 5: Japanese Patent Application Publication No. 2018-129169

[0009] Patent Document 6: International Publication No. 2019 / 146705 Summary of the invention

[0010] Problems to be solved by the invention

[0011] However, for a non-aqueous electrolyte for a battery containing 1,3-propene sultone as an additive, a performance of lowering the initial resistance of the battery is sometimes required.

[0012] An object of one embodiment of the present disclosure is to provide a non-aqueous electrolyte solution for a battery and a lithium secondary battery precursor capable of reducing the initial resistance of the battery, a lithium secondary battery having reduced initial resistance, and a method for producing the lithium secondary battery.

[0013] Means for solving problems

[0014] Means for solving the above-mentioned problems include the following aspects.

[0015] <1> A non-aqueous electrolyte for a battery, comprising:

[0016] Additive A, wherein the additive A is a compound (I) represented by the following formula (I); and

[0017] An additive B, wherein the additive B is at least one selected from the group consisting of a compound (II) represented by the following formula (II), a compound (III) that is at least one of a monofluorophosphate and a difluorophosphate, a compound (IV) represented by the following formula (IV), a compound (V) represented by the following formula (V), a compound (VI) represented by the following formula (VI), a compound (VII) represented by the following formula (VII), and a compound (VIII) represented by the following formula (VIII),

[0018] The content of the additive A is greater than 0.01 mass % and less than 0.5 mass % based on the total amount of the non-aqueous electrolyte solution for the battery.

[0019] [Chemical formula 1]

[0020]

[0021] In formula (I), R 11 Each independently represents a fluoro group (—F), a hydrocarbon group having 1 to 8 carbon atoms which may contain a fluoro group (—F) as a substituent, or a fluorocarbon group having 1 to 8 carbon atoms; and h represents an integer of 0 to 4.

[0022] [Chemical formula 2]

[0023]

[0024] In formula (II),

[0025] R 21 represents a group represented by formula (ii-1), a group represented by formula (ii-2), or a divalent hydrocarbon group having 3 to 6 carbon atoms,

[0026] * indicates the bonding position,

[0027] In formula (ii-1), R 22 represents an oxymethylene group (-OCH2-), an oxyethylene group (-OCH2CH2-), an oxa-group (-O-), or a divalent hydrocarbon group having 1 to 6 carbon atoms,

[0028] In formula (ii-2), R 23 It represents a hydrocarbon group having 1 to 8 carbon atoms.

[0029] In formula (IV),

[0030] M 41+ represents an alkali metal ion,

[0031] X 41 each independently represents a fluoro group (-F), a chloro group (-Cl), a bromo group (-Br), or an iodo group (-I),

[0032] Y41 represents a boron atom or a phosphorus atom,

[0033] R 41 each independently represents a single bond (-) or a divalent hydrocarbon group having 1 to 6 carbon atoms which may contain at least one group selected from the group consisting of a fluoro group (-F), a chloro group (-Cl), a bromo group (-Br), and an iodo group (-I) as a substituent,

[0034] iIn the above Y 41 When it is a boron atom, it represents 1 or 2. 41 When it is a phosphorus atom, it represents an integer of 1 to 3,

[0035] j in the above Y 41 When it is a boron atom, it represents 0 or 2. 41 In the case of a phosphorus atom, 0, 2 or 4 is represented.

[0036] In formula (V),

[0037] M 51+ represents an alkali metal ion,

[0038] R 51 and R 52 Each independently represents a fluoro group (—F), a hydrocarbon group having 1 to 3 carbon atoms which may have a fluoro group as a substituent, or a fluorocarbon group having 1 to 3 carbon atoms.

[0039] In formula (VI),

[0040] R 61 represents a hydrocarbon group having 1 to 8 carbon atoms which may contain at least one group selected from the group consisting of a fluoro group (-F), a chloro group (-Cl), a bromo group (-Br), an iodo group (-I), an oxa-group (-O-), a thiol group (-S-), a secondary amino group (-NH-), a tertiary amino group (-N<), a carbonyl group (>C=O), and a sulfonyl group (>S(=O)2) as a substituent,

[0041] L 61 It represents a single bond (-) or an oxazoline group (-O-).

[0042] In formula (VII),

[0043] M 71+ represents an alkali metal ion,

[0044] R 71 and R 72each independently represents a fluoro group (-F), a chloro group (-Cl), a bromo group (-Br), an iodo group (-I), a hydrocarbon group having 1 to 12 carbon atoms which may contain at least one group selected from the group consisting of a fluoro group (-F), a chloro group (-Cl), a bromo group (-Br), an iodo group (-I), and an oxa group (-O-) as a substituent, or a fluorocarbon group having 1 to 8 carbon atoms,

[0045] L 71 and L 72 represents a single bond (-) or an oxa-group (-O-), and L 71 and L 72 At least one of them is an oxa-group (-O-).

[0046] In formula (VIII),

[0047] R 81 each independently represents a fluoro group (-F), a chloro group (-Cl), a bromo group (-Br), or an iodo group (-I),

[0048] k represents an integer of 1 to 6.

[0049] <2> like <1> In the non-aqueous electrolyte for a battery, the mass ratio of the additive A to the additive B (the mass of the additive A / the mass of the additive B) is 0.05 to 0.5.

[0050] <3> like <1> or <2> The non-aqueous electrolyte for the battery, wherein the content of the additive A is 0.05 mass % to 0.4 mass % relative to the total amount of the non-aqueous electrolyte for the battery.

[0051] <4> like <1> ~ <3> In any one of the above non-aqueous electrolyte solutions for batteries, the content of the additive B is 0.01% by mass to 5.0% by mass based on the total amount of the non-aqueous electrolyte solution for batteries.

[0052] <5> like <1> The non-aqueous electrolyte for battery contains the compound (II) as the additive B. The content of the additive B is 0.01 mass % to 5.0 mass % relative to the total amount of the non-aqueous electrolyte for battery.

[0053] <6> like <1> The non-aqueous electrolyte for a battery comprises the compound (III) as the additive B, and the mass ratio of the additive A to the additive B (the mass of the additive A / the mass of the additive B) is 0.05 to 0.4.

[0054] <7> like <1> The non-aqueous electrolyte for the battery contains the compound (IV) as the additive B. The content of the additive B is 0.01% to 5.0% by mass relative to the total amount of the non-aqueous electrolyte for the battery.

[0055] <8> like <1> The non-aqueous electrolyte for the battery contains the compound (V) as the additive B. The content of the additive B is 0.1 mol / L to 6 mol / L relative to the total amount of the non-aqueous electrolyte for the battery.

[0056] <9> A lithium secondary battery precursor comprising:

[0057] housing, and

[0058] A positive electrode, a negative electrode, a separator, and an electrolyte contained in the housing;

[0059] The positive electrode is a positive electrode that can absorb and release lithium ions.

[0060] The negative electrode is a negative electrode that can absorb and release lithium ions.

[0061] The electrolyte is <1> ~ <8> The non-aqueous electrolyte solution for a battery as described above.

[0062] <10> like <9> In the lithium secondary battery precursor, the positive electrode comprises a lithium-containing composite oxide represented by the following formula (X) as a positive electrode active material.

[0063] LiNi a Co b Mn c O2…Formula (X)

[0064] [In formula (X), a, b and c are each independently greater than 0 and less than 1, and the total of a, b and c is greater than or equal to 0.99 and less than or equal to 1.00.]

[0065] <11> A method for manufacturing a lithium secondary battery, comprising the following steps:

[0066] Prepare <9> or <10> The lithium secondary battery precursor process, and

[0067] The lithium secondary battery precursor is subjected to charging and discharging steps.

[0068] <12> Lithium secondary battery, which is <9> or <10> The lithium secondary battery precursor is obtained by charging and discharging.

[0069] Effects of the Invention

[0070] According to one embodiment of the present disclosure, a non-aqueous electrolyte for a battery and a lithium secondary battery precursor capable of reducing the initial resistance of the battery, a lithium secondary battery having reduced initial resistance, and a method for producing the lithium secondary battery can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0071] [ Figure 1 ] is a schematic cross-sectional view showing a laminated battery as an example of a lithium secondary battery precursor of the present disclosure.

[0072] [ Figure 2 ] is a schematic cross-sectional view showing a button-type battery as another example of a lithium secondary battery precursor of the present disclosure. DETAILED DESCRIPTION

[0073] In the present disclosure, a numerical range expressed using "to" means a range including the numerical values ​​described before and after "to" as the lower limit and the upper limit.

[0074] In the numerical range recorded in stages in this disclosure, the upper limit or lower limit recorded in one numerical range can be replaced by the upper limit or lower limit of the numerical range recorded in other stages. In addition, in the numerical range recorded in this disclosure, the upper limit or lower limit of the numerical range can be replaced by the value shown in the embodiment.

[0075] In the present disclosure, when there are plural kinds of substances belonging to each component in the composition, the amount of each component in the composition refers to the total amount of the plural kinds of substances present in the composition unless otherwise specified.

[0076] In the present disclosure, a combination of preferred embodiments is a more preferred embodiment.

[0077] In the present disclosure, the term "process" includes not only independent processes but also processes that cannot be clearly distinguished from other processes as long as the intended purpose of the process can be achieved.

[0078] [Non-aqueous electrolyte for batteries]

[0079] The non-aqueous electrolyte solution for a battery of the present disclosure (hereinafter, also referred to as “non-aqueous electrolyte solution”) contains:

[0080] Additive A, wherein the additive A is a compound (I) represented by the following formula (I); and

[0081] An additive B, wherein the additive B is at least one selected from the group consisting of a compound (II) represented by the following formula (II), a compound (III) that is at least one of a monofluorophosphate and a difluorophosphate, a compound (IV) represented by the following formula (IV), a compound (V) represented by the following formula (V), a compound (VI) represented by the following formula (VI), a compound (VII) represented by the following formula (VII), and a compound (VIII) represented by the following formula (VIII),

[0082] The content of the additive A is greater than 0.01 mass % and less than 0.5 mass % based on the total amount of the non-aqueous electrolyte solution for the battery.

[0083] [Chemical formula 3]

[0084]

[0085] In formula (I), R 11 Each independently represents a fluoro group (—F), a hydrocarbon group having 1 to 8 carbon atoms which may contain a fluoro group (—F) as a substituent, or a fluorocarbon group having 1 to 8 carbon atoms; and h represents an integer of 0 to 4.

[0086] [Chemical formula 4]

[0087]

[0088] In formula (II),

[0089] R 21 represents a group represented by formula (ii-1), a group represented by formula (ii-2), or a divalent hydrocarbon group having 3 to 6 carbon atoms,

[0090] * indicates the bonding position,

[0091] In formula (ii-1), R 22 represents an oxymethylene group (-OCH2-), an oxyethylene group (-OCH2CH2-), an oxa-group (-O-), or a divalent hydrocarbon group having 1 to 6 carbon atoms,

[0092] In formula (ii-2), R 23 It represents a hydrocarbon group having 1 to 8 carbon atoms.

[0093] In formula (IV),

[0094] M 41+ represents an alkali metal ion,

[0095] X 41 each independently represents a fluoro group (-F), a chloro group (-Cl), a bromo group (-Br), or an iodo group (-I),

[0096] Y 41represents a boron atom or a phosphorus atom,

[0097] R 41 each independently represents a single bond (-) or a divalent hydrocarbon group having 1 to 6 carbon atoms which may contain at least one group selected from the group consisting of a fluoro group (-F), a chloro group (-Cl), a bromo group (-Br), and an iodo group (-I) as a substituent,

[0098] iIn the above Y 41 When it is a boron atom, it represents 1 or 2. 41 When it is a phosphorus atom, it represents an integer of 1 to 3,

[0099] j in the above Y 41 When it is a boron atom, it represents 0 or 2. 41 In the case of a phosphorus atom, 0, 2 or 4 is represented.

[0100] In formula (V),

[0101] M 51+ represents an alkali metal ion,

[0102] R 51 and R 52 Each independently represents a fluoro group (—F), a hydrocarbon group having 1 to 3 carbon atoms which may have a fluoro group as a substituent, or a fluorocarbon group having 1 to 3 carbon atoms.

[0103] In formula (VI),

[0104] R 61 represents a hydrocarbon group having 1 to 8 carbon atoms which may contain at least one group selected from the group consisting of a fluoro group (-F), a chloro group (-Cl), a bromo group (-Br), an iodo group (-I), an oxa-group (-O-), a thiol group (-S-), a secondary amino group (-NH-), a tertiary amino group (-N<), a carbonyl group (>C=O), and a sulfonyl group (>S(=O)2) as a substituent,

[0105] L 61 It represents a single bond (-) or an oxazoline group (-O-).

[0106] In formula (VII),

[0107] M 71+ represents an alkali metal ion,

[0108] R 71 and R 72each independently represents a fluoro group (-F), a chloro group (-Cl), a bromo group (-Br), an iodo group (-I), a hydrocarbon group having 1 to 12 carbon atoms which may contain at least one group selected from the group consisting of a fluoro group (-F), a chloro group (-Cl), a bromo group (-Br), an iodo group (-I), and an oxa group (-O-) as a substituent, or a fluorocarbon group having 1 to 8 carbon atoms,

[0109] L 71 and L 72 represents a single bond (-) or an oxa-group (-O-), and L 71 and L 72 At least one of them is an oxa-group (-O-).

[0110] In formula (VIII),

[0111] R 81 each independently represents a fluoro group (-F), a chloro group (-Cl), a bromo group (-Br), or an iodo group (-I),

[0112] k represents an integer of 1 to 6.

[0113] The inventors of the present application have found through research that there is room for further improvement in the performance of reducing the initial resistance of a battery in a non-aqueous electrolyte solution containing an additive A represented by 1,3-propene sultone.

[0114] Specifically, it was found that when Additive A and Additive B are used together, when the content of Additive A relative to the total amount of the non-aqueous electrolyte for the battery (hereinafter also simply referred to as "the content of Additive A") is 0.5 mass % or more, there is a tendency for the initial resistance of the battery to increase.

[0115] On the other hand, it was found that when the additive A and the additive B were used in combination, when the content of the additive A was 0.01 mass % or less, the initial resistance of the battery tended to increase.

[0116] In view of the above-mentioned problem of initial resistance, in the non-aqueous electrolyte of the present disclosure, the content of the additive A is limited to a range of greater than 0.01 mass % and less than 0.5 mass %.

[0117] This can reduce the initial resistance of the battery.

[0118] <Additive A>

[0119] The non-aqueous electrolyte of the present disclosure contains the additive A which is the compound (I) represented by the above formula (I).

[0120] The additive A (ie, compound (I)) contained in the non-aqueous electrolyte may be only one kind or two or more kinds.

[0121] Compound (I) is an unsaturated sultone compound as shown in the above structure.

[0122] In formula (I), R 11 Each independently represents a "fluoro group (-F)", a "hydrocarbon group having 1 to 8 carbon atoms which may contain a fluoro group (-F) as a substituent", or a "carbon fluoro group having 1 to 8 carbon atoms", and h represents an integer of 0 to 4. It should be noted that in formula (I), (R 11 ) h The structure in which the bonding line of pierces the five-membered ring of the unsaturated sultone means that the four hydrogen atoms contained in the five-membered ring of the unsaturated sultone (…S-CH=CH-CH2-O…) can be substituted independently by a “fluoro group (—F)”, a “hydrocarbon group having 1 to 8 carbon atoms which can contain a fluoro group (—F) as a substituent”, or a “carbon fluoride group having 1 to 8 carbon atoms”. In addition, the so-called “hydrocarbon group” is not limited to an aliphatic hydrocarbon group having a straight-chain structure, and may be a group having at least one structure selected from the group consisting of a branched structure, a cyclic structure, and a carbon-carbon unsaturated bond structure (a carbon-carbon double bond structure and a carbon-carbon triple bond structure), and may also be an aromatic hydrocarbon group. That is, alkyl groups, alkenyl groups, alkynyl groups, aryl groups, etc. are all included in the “hydrocarbon group”. In addition, the so-called "may contain a fluorine group (-F) as a substituent" means that in addition to the hydrocarbon group that does not contain a fluorine group (-F) as a substituent, it also includes a hydrocarbon group obtained by replacing a part of the hydrogen atoms of the hydrocarbon group with a fluorine group (-F), and the number of fluorine groups (-F) is not particularly limited. In addition, the so-called "carbon fluoro group" refers to a group obtained by replacing all the hydrogen atoms of the hydrocarbon group with a fluorine group (-F). In addition, regarding the "number of carbon atoms", in the case of a "hydrocarbon group" or "carbon fluoro group" having a substituent, it refers to the number including the carbon atoms of the substituent. For example, for trifluoromethylphenyl (-C6H5CF3), it is understood as follows: 7, which is obtained by adding the carbon atom number of phenyl (6) and the carbon atom number of trifluoromethyl (1), is the carbon atom number of trifluoromethylphenyl (-C6H5CF3) as a hydrocarbon group containing a fluorine group (-F).

[0123] R 11 In the case of "a hydrocarbon group having 1 to 8 carbon atoms which may contain a fluorine group (-F) as a substituent" or "a fluorocarbon group having 1 to 8 carbon atoms", the number of carbon atoms in the hydrocarbon group and the fluorocarbon group is preferably 6 or less, more preferably 5 or less, further preferably 4 or less, and particularly preferably 3 or less.

[0124] As R 11, preferably a fluoro group (-F), an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alkynyl group having 2 to 8 carbon atoms, an aryl group having 6 to 8 carbon atoms, an alkyl group having 1 to 8 carbon atoms containing a fluoro group (-F), an alkenyl group having 2 to 8 carbon atoms containing a fluoro group (-F), an alkynyl group having 2 to 8 carbon atoms containing a fluoro group (-F), an aryl group having 6 to 8 carbon atoms containing a fluoro group (-F), a perfluoroalkyl group having 1 to 8 carbon atoms, a perfluoroalkenyl group having 2 to 8 carbon atoms, a perfluoroalkynyl group having 2 to 8 carbon atoms, and a perfluoroaryl group having 6 to 8 carbon atoms; particularly preferably a fluoro group (-F), a monofluoromethyl group (-CH2F), a difluoromethyl group (-CHF2), a trifluoromethyl group (-CF3), a methyl group (-CH3), and an ethyl group (-CH2CH3).

[0125] h is an integer of 0 to 4, preferably 0, 1, or 2, more preferably 0 or 1, and particularly preferably 0. It should be noted that h being 0 means that there is no R 11 , refers to becoming 1,3-propene sultone.

[0126] Specific examples of compound (I) include the following compounds (I-1) to (I-21), but compound (I) is not limited to these specific examples.

[0127] Among them, compound (I-1) is particularly preferred.

[0128] The compound (I-1) is 1,3-propene sultone.

[0129] [Chemical formula 5]

[0130]

[0131] The content of the additive A (ie, compound (I)) relative to the total amount of the non-aqueous electrolyte is greater than 0.01% by mass and less than 0.5% by mass.

[0132] Thus, the performance of reducing the initial resistance of the battery is improved compared with the case where the additive A is 0.01 mass % or less and the case where the additive A is 0.5 mass % or more.

[0133] From the viewpoint of more effectively obtaining the effect brought by the nonaqueous electrolyte of the present disclosure, the content of additive A is preferably 0.02% by mass or more, more preferably 0.03% by mass or more, further preferably 0.04% by mass or more, preferably 0.4% by mass or less, more preferably 0.3% by mass or less, further preferably 0.2% by mass or less. In addition, it can also be set to 0.05% by mass or more, 0.1% by mass or more.

[0134] <Additive B>

[0135] The non-aqueous electrolyte of the present disclosure contains an additive B, wherein the additive B is at least one selected from the group consisting of a compound (II) represented by the above formula (II), a compound (III) that is at least one of a monofluorophosphate and a difluorophosphate, a compound (IV) represented by the above formula (IV), a compound (V) represented by the above formula (V), a compound (VI) represented by the above formula (VI), a compound (VII) represented by the above formula (VII), and a compound (VIII) represented by the above formula (VIII).

[0136] The additive B contained in the non-aqueous electrolyte may be only one kind or two or more kinds.

[0137] From the viewpoint of more effectively obtaining the effect brought by the nonaqueous electrolyte of the present disclosure, the content of the additive B relative to the total amount of the nonaqueous electrolyte for battery is usually 0.01% by mass to 5.0% by mass, preferably 0.03% by mass or more, more preferably 0.05% by mass or more, further preferably 0.1% by mass or more, particularly preferably 0.3% by mass or more, preferably 3.0% by mass or less, more preferably 2.0% by mass or less, further preferably 1.0% by mass or less, particularly preferably 0.9% by mass or less. In addition, it can also be set to 0.8% by mass or less, 0.6% by mass or less.

[0138] In the non-aqueous electrolyte of the present disclosure, from the viewpoint of more effectively obtaining the effect brought about by the non-aqueous electrolyte of the present disclosure, the mass ratio of additive A to additive B (i.e., the ratio of the mass of additive A to the mass of additive B, the ratio obtained by dividing the mass of additive A by the mass of additive B; hereinafter also referred to as the mass ratio [additive A / additive B]) is usually 0.05 to 0.5, preferably 0.06 or more, preferably 0.45 or less. In addition, it can also be set to 0.08 or more, 0.09 or more, 0.1 or more, 0.2 or more, and in addition, it can also be set to 0.4 or less, 0.3 or less.

[0139] Additive B is at least one selected from the group consisting of compound (II) represented by the above formula (II), compound (III) which is at least one of monofluorophosphate and difluorophosphate, compound (IV) represented by the above formula (IV), compound (V) represented by the above formula (V), compound (VI) represented by the above formula (VI), compound (VII) represented by the above formula (VII), and compound (VIII) represented by the above formula (VIII). The following describes each compound serving as additive B.

[0140] (Compound (II))

[0141] Compound (II) is a compound represented by the following formula (II).

[0142] [Chemical formula 6]

[0143]

[0144] In formula (II),

[0145] R 21 represents "a group represented by the formula (ii-1)", "a group represented by the formula (ii-2)", or "a divalent hydrocarbon group having 3 to 6 carbon atoms",

[0146] * indicates "bonding position",

[0147] In formula (ii-1), R 22 represents "oxymethylene (-OCH2-)", "oxyethylene (-OCH2CH2-)", "oxa-group (-O-)", or "a divalent hydrocarbon group having 1 to 6 carbon atoms",

[0148] In formula (ii-2), R 23 It means a "hydrocarbon group having 1 to 8 carbon atoms".

[0149] It should be noted that in formula (ii-1) and formula (ii-2), * represents a "bonding position", which means that the * portion is bonded to two oxygen atoms of formula (II) respectively, and R 21 In the case of a "group represented by formula (ii-1)" or a "group represented by formula (ii-2)", a five-membered ring of ethylene sulfate is formed (...S(=O)2-O-CH2-CHR-O...). In addition, a "divalent hydrocarbon group" refers to a hydrocarbon group having two bonding positions. Like the aforementioned "hydrocarbon group", it is not limited to an aliphatic hydrocarbon group having a straight-chain structure, but may also be a group having at least one structure selected from the group consisting of a branched structure, a cyclic structure, and a carbon-carbon unsaturated bond structure (a carbon-carbon double bond structure and a carbon-carbon triple bond structure). In addition, it may also be an aromatic hydrocarbon group. That is, alkylene, alkenylene, alkynylene, arylene, etc. are all included in the "divalent hydrocarbon group". In addition, the so-called R 22 "Oxymethylene (-OCH2-)" means that the oxygen group (-O-) of the oxymethylene group is bonded to the sulfonyl group (>S(=O)2) to form a five-membered ring of sulfate ester (...S(=O)2-O-CH2-CHR-O...), so R 22 "Oxyethylene (-OCH2CH2-)" means a six-membered ring of propylene sulfate (...S(=O)2-O-CH2-CH2-CHR-O...), so R 22 "Oxa (-O-)" means a four-membered ring (...S(=O)2-O-CHR-O...) formed of methylene sulfate.

[0150] R 21 In the case of a "divalent hydrocarbon group having 3 to 6 carbon atoms", the hydrocarbon group preferably has 5 or less carbon atoms, and more preferably has 4 or less carbon atoms.

[0151] R 22 In the case of a "divalent hydrocarbon group having 1 to 6 carbon atoms", the hydrocarbon group preferably has 5 or less carbon atoms, more preferably 4 or less, further preferably 3 or less, and particularly preferably 2 or less carbon atoms.

[0152] R 23 The term "hydrocarbon group having 1 to 8 carbon atoms" refers to a hydrocarbon group having preferably 6 or less carbon atoms, more preferably 5 or less carbon atoms, further preferably 4 or less carbon atoms, and particularly preferably 3 or less carbon atoms.

[0153] As R 21 , preferably a group represented by formula (ii-1), a group represented by formula (ii-2), an alkylene group having 3 to 6 carbon atoms, or an alkenylene group having 3 to 6 carbon atoms, further preferably a group represented by formula (ii-1), a group represented by formula (ii-2), or an n-propylene group (-CH2CH2CH2-), and particularly preferably a group represented by formula (ii-1).

[0154] As R 22 , preferably oxymethylene (-OCH2-), oxyethylene (-OCH2CH2-), oxazo (-O-), alkylene having 1 to 6 carbon atoms, alkenylene having 1 to 6 carbon atoms, further preferably oxymethylene (-OCH2-), oxyethylene (-OCH2CH2-), oxazo (-O-), methylene (-CH2-), ethylene (-CH2CH2-), n-propylene (-CH2CH2CH2-), particularly preferably oxymethylene (-OCH2-).

[0155] As R 23 , preferably an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alkynyl group having 2 to 8 carbon atoms, or an aryl group having 6 to 8 carbon atoms, further preferably a methyl group (-CH3), an ethyl group (-CH2CH3), a vinyl group (-CH=CH2), a n-propyl group (-CH2CH2CH3), a n-butyl group (-CH2CH2CH2CH3), or a phenyl group (-C6H5), particularly preferably a methyl group (-CH3), an ethyl group (-CH2CH3), a vinyl group (-CH=CH2), or a n-propyl group (-CH2CH2CH3).

[0156] Specific examples of compound (II) include the following compounds (II-1) to (II-3).

[0157] [Chemical formula 7]

[0158]

[0159] In the case where the non-aqueous electrolyte of the present disclosure contains compound (II) as additive B, from the viewpoint of more effectively obtaining the effect brought by the non-aqueous electrolyte of the present disclosure, the content of compound (II) relative to the total amount of the non-aqueous electrolyte is usually 0.01% by mass to 5.0% by mass, preferably 0.03% by mass or more, more preferably 0.05% by mass or more, further preferably 0.1% by mass or more, particularly preferably 0.3% by mass or more, preferably 3.0% by mass or less, more preferably 2.0% by mass or less, further preferably 1.0% by mass or less, particularly preferably 0.9% by mass or less. In addition, it can also be set to 0.8% by mass or less, 0.6% by mass or less.

[0160] When the non-aqueous electrolyte of the present disclosure contains compound (II) as additive B, from the viewpoint of more effectively obtaining the effect brought about by the non-aqueous electrolyte of the present disclosure, the mass ratio of additive A to compound (II) (i.e., the ratio of the mass of additive A to the mass of compound (II), the ratio obtained by dividing the mass of additive A by the mass of compound (II); hereinafter also referred to as the mass ratio [additive A / compound (II)]) is usually 0.05 to 0.5, preferably 0.06 or more, and preferably 0.45 or less. In addition, it can also be set to 0.08 or more, 0.09 or more, 0.1 or more, 0.2 or more, and can also be set to 0.4 or less, 0.3 or less.

[0161] (Compound (III))

[0162] Compound (III) is at least one of a monofluorophosphate and a difluorophosphate.

[0163] The cations of monofluorophosphate and difluorophosphate are preferably lithium ions (Li + ), sodium ion (Na + ), potassium ion (K + ), particularly preferably lithium ion (Li + ).

[0164] Specific examples of compound (III) include the following compound (III-1) and the following compound (III-2).

[0165] The following compound (III-1) is lithium difluorophosphate, and the compound (III-2) is lithium monofluorophosphate.

[0166] [Chemical formula 8]

[0167]

[0168] Compound (III) may be only one of the monofluorophosphate and the difluorophosphate, or may be both of the monofluorophosphate and the difluorophosphate.

[0169] In the case where the non-aqueous electrolyte of the present disclosure contains compound (III) as additive B, from the viewpoint of more effectively obtaining the effect brought by the non-aqueous electrolyte of the present disclosure, the content of compound (III) relative to the total amount of the non-aqueous electrolyte is usually 0.01% by mass to 5.0% by mass, preferably 0.03% by mass or more, more preferably 0.05% by mass or more, further preferably 0.1% by mass or more, particularly preferably 0.3% by mass or more, preferably 3.0% by mass or less, more preferably 2.0% by mass or less, further preferably 1.0% by mass or less, particularly preferably 0.9% by mass or less. In addition, it can also be set to 0.8% by mass or less, 0.6% by mass or less.

[0170] When the non-aqueous electrolyte of the present disclosure contains compound (III) as additive B, from the viewpoint of more effectively obtaining the effect brought about by the non-aqueous electrolyte of the present disclosure, the mass ratio of additive A to compound (III) (i.e., the ratio of the mass of additive A to the mass of compound (III), the ratio obtained by dividing the mass of additive A by the mass of compound (III); hereinafter also referred to as the mass ratio [additive A / compound (III)]) is usually 0.05 to 0.5, preferably 0.06 or more, and preferably 0.45 or less. In addition, it can also be set to 0.08 or more, 0.09 or more, 0.1 or more, 0.2 or more, and can also be set to 0.4 or less, 0.3 or less.

[0171] (Compound (IV))

[0172] Compound (IV) is a compound represented by the following formula (IV).

[0173] [Chemical formula 9]

[0174]

[0175] In formula (IV),

[0176] M 41+ stands for "alkali metal ion",

[0177] X 41 Each independently represents a "fluoro group (-F)", a "chloro group (-Cl)", a "bromo group (-Br)", or an "iodo group (-I)",

[0178] Y 41 means "boron atom" or "phosphorus atom",

[0179] R 41 Each independently represents a "single bond (-)" or a "divalent hydrocarbon group having 1 to 6 carbon atoms which may contain at least one group selected from the group consisting of a fluoro group (-F), a chloro group (-Cl), a bromo group (-Br), and an iodo group (-I) as a substituent",

[0180] In the above Y 41 When i is a boron atom, it represents 1 or 2. 41 When it is a phosphorus atom, i represents an integer of 1 to 3,

[0181] In the above Y 41 When j is a boron atom, it represents 0 or 2. 41 When it is a phosphorus atom, j represents 0, 2 or 4.

[0182] It should be noted that R 41 It can be a "single bond (-)", so-called R 41 "Single bond (-)" means 41 Two adjacent carbonyl groups (>C=O) are directly bonded, which refers to the oxalate ion (C2O4 2- ) becomes a multidentate ligand and forms an oxalate complex. In addition, "divalent hydrocarbon group" is the same as the aforementioned divalent hydrocarbon group. In addition, the so-called "may include at least one group selected from the group consisting of fluoro group (-F), chloro group (-Cl), bromo group (-Br), and iodo group (-I) as a substituent", refers to a hydrocarbon group including a part of the hydrogen atoms of the hydrocarbon group being replaced by any group in fluoro group (-F), chloro group (-Cl), bromo group (-Br), iodo group (-I) in addition to the hydrocarbon group not including fluoro group (-F) as a substituent, and the number and combination of fluoro group (-F), chloro group (-Cl), bromo group (-Br), iodo group (-I) are not particularly limited.

[0183] R 41 In the case of "a divalent hydrocarbon group having 1 to 6 carbon atoms which may contain at least one group selected from the group consisting of a fluorine group (-F), a chlorine group (-Cl), a bromine group (-Br), and an iodine group (-I) as a substituent", the number of carbon atoms of the hydrocarbon group is preferably 5 or less, more preferably 4 or less, and further preferably 3 or less.

[0184] M 41+ Preferably, lithium ion (Li + ), sodium ion (Na + ), potassium ion (K + ), particularly preferably lithium ion (Li + ).

[0185] As X 41, preferably a fluorine group (-F) or a chlorine group (-Cl), and particularly preferably a fluorine group (-F).

[0186] Y 41 represents a boron atom or a phosphorus atom, in Y 41 When it is a boron atom, i represents 1 or 2. 41 When Y is a phosphorus atom, i represents an integer of 1 to 3. 41 When it is a boron atom, j represents 0 or 2. 41 When it is a phosphorus atom, j represents 0, 2, or 4, and Y 41 When the boron atom is present, the combinations of i and j are i=1 and j=2, i=2 and j=0, and Y 41 When the atom is a phosphorus atom, the combinations of i and j are a combination of i=1 and j=4, a combination of i=2 and j=2, and a combination of i=3 and j=0.

[0187] As R 41 , preferably a single bond (-), an alkylene group having 1 to 6 carbon atoms, an alkenylene group having 2 to 6 carbon atoms, an alkynylene group having 2 to 6 carbon atoms, an alkylene group having 1 to 6 carbon atoms containing a fluorine group (-F), an alkenylene group having 2 to 6 carbon atoms containing a fluorine group (-F), an alkynylene group having 2 to 6 carbon atoms containing a fluorine group (-F); preferably a single bond (-), a methylene group (-CH2-), an ethylene group (-CH2CH2-), an n-propylene group (-CH2CH2CH2-); particularly preferably a single bond (-).

[0188] Specific examples of compound (IV) include the following compounds (IV-1) to (IV-4).

[0189] Compound (IV-1) is lithium bis(oxalato)borate (LiBOB), compound (IV-2) is lithium difluorooxalatoborate (LiDFOB), compound (IV-3) is lithium tetrafluorooxalatophosphate (LiTFOP), and compound (IV-4) is lithium difluorobis(oxalato)phosphate (LiDF BOP).

[0190] [Chemical formula 10]

[0191]

[0192] In the case where the non-aqueous electrolyte of the present disclosure contains compound (IV) as additive B, from the viewpoint of more effectively obtaining the effect brought by the non-aqueous electrolyte of the present disclosure, the content of compound (IV) relative to the total amount of the non-aqueous electrolyte is usually 0.01% by mass to 5.0% by mass, preferably 0.03% by mass or more, more preferably 0.05% by mass or more, further preferably 0.1% by mass or more, particularly preferably 0.3% by mass or more, preferably 3.0% by mass or less, more preferably 2.0% by mass or less, further preferably 1.0% by mass or less, particularly preferably 0.9% by mass or less. In addition, it can also be set to 0.8% by mass or less, 0.6% by mass or less.

[0193] When the non-aqueous electrolyte of the present disclosure contains compound (IV) as additive B, from the viewpoint of more effectively obtaining the effect brought about by the non-aqueous electrolyte of the present disclosure, the mass ratio of additive A to compound (IV) (i.e., the ratio of the mass of additive A to the mass of compound (IV), the ratio obtained by dividing the mass of additive A by the mass of compound (IV); hereinafter also referred to as the mass ratio [additive A / compound (IV)]) is usually 0.05 to 0.5, preferably 0.06 or more, and preferably 0.45 or less. In addition, it can also be set to 0.08 or more, 0.09 or more, 0.1 or more, 0.2 or more, and can also be set to 0.4 or less, 0.3 or less.

[0194] (Compound (V))

[0195] Compound (V) is a compound represented by the following formula (V).

[0196] [Chemical formula 11]

[0197]

[0198] In formula (V),

[0199] M 51+ stands for "alkali metal ion",

[0200] R 51 and R 52 Each independently represents a "fluoro group (—F)", a "hydrocarbon group having 1 to 3 carbon atoms which may contain a fluoro group as a substituent", or a "fluorocarbon group having 1 to 3 carbon atoms".

[0201] In addition, the "hydrocarbon group" and the "fluorocarbon group" are the same as the above-mentioned "hydrocarbon group" and "fluorocarbon group".

[0202] M 51 Preferably, lithium ion (Li + ), sodium ion (Na+ ), potassium ion (K + ), particularly preferably lithium ion (Li + ).

[0203] As R 51 , R 52 , preferably a fluoro group (-F), an alkyl group having 1 to 3 carbon atoms, an alkyl group having 1 to 3 carbon atoms containing a fluoro group (-F), or a perfluoroalkyl group having 1 to 3 carbon atoms, and particularly preferably a fluoro group (-F), a monofluoromethyl group (-CH2F), a difluoromethyl group (-CHF2), a trifluoromethyl group (-CF3), a pentafluoroethyl group (-CF2CF3), or a heptafluoropropyl group (-CF2CF2CF3).

[0204] Specific examples of the compound (V) include the following compound (V-1) and the following compound (V-2).

[0205] Compound (V-1) is lithium bis(fluorosulfonyl)imide, and compound (V-2) is lithium bis(trifluoromethanesulfonyl)imide. It should be noted that lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, etc. can also be used as electrolytes described later (more specifically, organic acid anion salts of lithium salts containing fluorine described later.), therefore, even in the case of non-aqueous electrolytes intended to be used as electrolytes, as long as other specific invention matters (constituent elements) involved in the present disclosure are met, they are also equivalent to the non-aqueous electrolytes of the present disclosure.

[0206] [Chemical formula 12]

[0207]

[0208] In the case where the non-aqueous electrolyte of the present disclosure contains compound (V) as additive B, from the viewpoint of more effectively obtaining the effect brought by the non-aqueous electrolyte of the present disclosure, the content of compound (V) relative to the total amount of the non-aqueous electrolyte is usually 0.01% by mass to 5.0% by mass, preferably 0.03% by mass or more, more preferably 0.05% by mass or more, further preferably 0.1% by mass or more, particularly preferably 0.3% by mass or more, preferably 3.0% by mass or less, more preferably 2.0% by mass or less, further preferably 1.0% by mass or less, particularly preferably 0.9% by mass or less. In addition, it can also be set to 0.8% by mass or less, 0.6% by mass or less. On the other hand, when compound (V) is used as the electrolyte described later, the content of compound (V) relative to the total amount of the non-aqueous electrolyte is preferably 0.05 mol / L (M (Molar)) or more, more preferably 0.1 mol / L (M), further preferably 0.3 mol / L (M), particularly preferably 0.5 mol / L (M) or more, preferably 6 mol / L (M) or less, more preferably 3 mol / L (M) or less, further preferably 1 mol / L (M) or less, and particularly preferably 0.7 mol / L (M) or less.

[0209] When the non-aqueous electrolyte of the present disclosure contains compound (V) as additive B, from the viewpoint of more effectively obtaining the effect brought about by the non-aqueous electrolyte of the present disclosure, the mass ratio of additive A to compound (V) (i.e., the ratio of the mass of additive A to the mass of compound (V), the ratio obtained by dividing the mass of additive A by the mass of compound (V); hereinafter also referred to as the mass ratio [additive A / compound (V)]) is usually 0.05 to 0.5, preferably 0.06 or more, and preferably 0.45 or less. In addition, it can also be set to 0.08 or more, 0.09 or more, 0.1 or more, 0.2 or more, and can also be set to 0.4 or less, 0.3 or less.

[0210] (Compound (VI))

[0211] Compound (VI) is a compound represented by the following formula (VI).

[0212] [Chemical formula 13]

[0213]

[0214] In formula (VI),

[0215] R 61It means "a hydrocarbon group having 1 to 8 carbon atoms which may contain at least one group selected from the group consisting of a fluoro group (-F), a chloro group (-Cl), a bromo group (-Br), an iodo group (-I), an oxa-group (-O-), a thiol group (-S-), a secondary amino group (-NH-), a tertiary amino group (-N<), a carbonyl group (>C=O), and a sulfonyl group (>S(=O)2) as a substituent",

[0216] L 61 It represents a single bond (-) or an oxazoline group (-O-).

[0217] It should be noted that the "hydrocarbon group" is the same as the aforementioned hydrocarbon group. In addition, the phrase "may contain at least one group selected from the group consisting of a fluoro group (-F), a chloro group (-Cl), a bromo group (-Br), an iodo group (-I), an oxa-group (-O-), a thiol group (-S-), a secondary amino group (-NH-), a tertiary amino group (-N<), a carbonyl group (>C=O), and a sulfonyl group (>S(=O)2) as a substituent" means that in addition to hydrocarbon groups that do not contain a fluoro group (-F) or the like as a substituent, hydrocarbon groups also include hydrocarbon groups in which a part of the hydrogen atoms of the hydrocarbon group is replaced by any of the following groups: a fluoro group (-F), a chloro group (-Cl), a bromo group (-Br), an iodo group (-I), a thiol group (-S-), a secondary amino group (-NH-), a tertiary amino group (-N<), a carbonyl group (>C=O), and a sulfonyl group (>S(=O)2) The number and combination of fluoro (-F), chloro (-Cl), bromo (-Br), iodo (-I), oxa-yl (-O-), thio (-S-), secondary amino (-NH-), tertiary amino (-N<), carbonyl (>C=O), and sulfonyl (>S(=O)2) are not particularly limited.

[0218] R 61 It is "a hydrocarbon group having 1 to 8 carbon atoms which may contain at least one group selected from the group consisting of a fluoro group (-F), a chloro group (-Cl), a bromo group (-Br), an iodo group (-I), an oxa-group (-O-), a thiol group (-S-), a secondary amino group (-NH-), a tertiary amino group (-N<), a carbonyl group (>C=O), and a sulfonyl group (>S(=O)2) as a substituent", and the number of carbon atoms of the hydrocarbon group is preferably 6 or less, more preferably 5 or less, further preferably 4 or less, and particularly preferably 3 or less.

[0219] As R 61, preferably an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alkynyl group having 2 to 8 carbon atoms, or an aryl group having 6 to 8 carbon atoms, preferably a methyl group (-CH3), an ethyl group (-CH2CH3), a vinyl group (-CH=CH2), a n-propyl group (-CH2CH2CH3), or a n-butyl group (-CH2CH2CH2CH3), and particularly preferably a methyl group (-CH3) or an ethyl group (-CH2CH3).

[0220] As L 61 , particularly preferably a single bond (-).

[0221] Specific examples of compound (VI) include the following compound (VI-1) and the following compound (VI-2).

[0222] Compound (VI-1) is trifluoromethyl methyl sulfone, and compound (VI-2) is trifluoromethyl ethyl sulfone.

[0223] [Chemical formula 14]

[0224]

[0225] In the case where the non-aqueous electrolyte of the present disclosure contains compound (VI) as additive B, from the viewpoint of more effectively obtaining the effect brought by the non-aqueous electrolyte of the present disclosure, the content of compound (VI) relative to the total amount of the non-aqueous electrolyte is usually 0.01% by mass to 5.0% by mass, preferably 0.03% by mass or more, more preferably 0.05% by mass or more, further preferably 0.1% by mass or more, particularly preferably 0.3% by mass or more, preferably 3.0% by mass or less, more preferably 2.0% by mass or less, further preferably 1.0% by mass or less, particularly preferably 0.9% by mass or less. In addition, it can also be set to 0.8% by mass or less, 0.6% by mass or less.

[0226] When the non-aqueous electrolyte of the present disclosure contains compound (VI) as additive B, from the viewpoint of more effectively obtaining the effect brought about by the non-aqueous electrolyte of the present disclosure, the mass ratio of additive A to compound (VI) (i.e., the ratio of the mass of additive A to the mass of compound (VI), the ratio obtained by dividing the mass of additive A by the mass of compound (VI); hereinafter also referred to as the mass ratio [additive A / compound (VI)]) is usually 0.05 to 0.5, preferably 0.06 or more, and preferably 0.45 or less. In addition, it can also be set to 0.08 or more, 0.09 or more, 0.1 or more, 0.2 or more, and can also be set to 0.4 or less, 0.3 or less.

[0227] (Compound (VII))

[0228] Compound (VII) is a compound represented by the following formula (VII).

[0229] [Chemical formula 15]

[0230]

[0231] In formula (VII),

[0232] M 71+ stands for "alkali metal ion",

[0233] R 71 and R 72 each independently represents a "fluoro group (-F)", a "chloro group (-Cl)", a "bromo group (-Br)", an "iodo group (-I)", a "hydrocarbon group having 1 to 12 carbon atoms which may contain at least one group selected from the group consisting of a fluoro group (-F), a chloro group (-Cl), a bromo group (-Br), an iodo group (-I), and an oxa group (-O-) as a substituent", or a "fluorocarbon group having 1 to 8 carbon atoms",

[0234] L 71 and L 72 represents a "single bond (-)" or an "oxa-group (-O-)", and L 71 and L 72 At least one of them is an oxa-group (-O-).

[0235] It should be noted that "hydrocarbon group", "carbon fluoride group", "single bond (-)" and "oxa-group (-O-)" are the same as those described above. In addition, the so-called "may contain at least one group selected from the group consisting of fluoro group (-F), chloro group (-Cl), bromo group (-Br), iodo group (-I), and oxa-group (-O-) as a substituent" means that in addition to hydrocarbon groups that do not contain fluoro group (-F) as a substituent, it also includes hydrocarbon groups in which a part of the hydrogen atoms of the hydrocarbon group is replaced by any group of fluoro group (-F), chloro group (-Cl), bromo group (-Br), iodo group (-I), and hydrocarbon groups in which a part of the carbon atoms of the hydrocarbon group is replaced by oxa-group (-O-). The number and combination of fluoro group (-F), chloro group (-Cl), bromo group (-Br), iodo group (-I), and oxa-group (-O-) are not particularly limited. In addition, L 71 and L 72 Indicates "single bond (-)" or "oxa-group (-O-)", so-called L 71 "Single bond (-)" means that 71 Adjacent R 71 and sulfonyl (>S(=O)2) directly bonded, so-called L 71 "O-" refers to the formation of R 71-OS(=O)2- structure. Similarly, the so-called L 72 "Single bond (-)" means that 72 Adjacent R 72 Directly bonded to the carbonyl group (>C=O), so-called L 72 "O-" means an oxa-group (-O-) forming R 72 The structure of -OC(=O)-.

[0236] M 71 Preferably, lithium ion (Li + ), sodium ion (Na + ), potassium ion (K + ), particularly preferably lithium ion (Li + ).

[0237] As R 71 , preferably a fluoro group (-F), an alkyl group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, an alkynyl group having 2 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkyl group having 1 to 12 carbon atoms including a fluoro group (-F), an alkenyl group having 2 to 12 carbon atoms including a fluoro group (-F), an alkynyl group having 2 to 12 carbon atoms including a fluoro group (-F), an aryl group having 6 to 12 carbon atoms including a fluoro group (-F), an alkyl group having 1 to 12 carbon atoms including an oxa-group (-O-), an alkenyl group having 2 to 12 carbon atoms including an oxa-group (-O-), an alkynyl group having 2 to 12 carbon atoms including an oxa-group (-O-), an aryl group having 6 to 12 carbon atoms including an oxa-group (-O-), a fluoro group (-F) and an oxa-group (-O-) The invention also includes an alkyl group having 2 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms including a fluoro group (-F) and an oxa group (-O-), an alkynyl group having 2 to 12 carbon atoms including a fluoro group (-F) and an oxa group (-O-), and an aryl group having 6 to 12 carbon atoms including a fluoro group (-F) and an oxa group (-O-). Preferably, the fluoro group (-F), a methyl group (-CH3), a trifluoromethyl group (-CF3), an ethyl group (-CH2CH3), a 2,2,2-trifluoroethyl group (-CH2CF3), a phenyl group (-C6H5), a p-methylphenyl group (-C6H4CH3), a p-trifluoromethylphenyl group (-C6H4CF3), and a p-trifluoromethoxyphenyl group (-C6H4OCF3). A fluoro group (-F) and a trifluoromethyl group (-CF3) are further preferred, and a fluoro group (-F) is particularly preferred.

[0238] As R 72, preferably an alkyl group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, an alkynyl group having 2 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkyl group having 1 to 12 carbon atoms including a fluoro group (-F), an alkenyl group having 2 to 12 carbon atoms including a fluoro group (-F), an alkynyl group having 2 to 12 carbon atoms including a fluoro group (-F), an aryl group having 6 to 12 carbon atoms including a fluoro group (-F), an alkyl group having 1 to 12 carbon atoms including an oxazoline group (-O-), an oxazoline group ( -O-) containing an alkenyl group having 2 to 12 carbon atoms, an alkynyl group having 2 to 12 carbon atoms including an oxa group (-O-), an aryl group having 6 to 12 carbon atoms including an oxa group (-O-), an alkyl group having 1 to 12 carbon atoms including a fluoro group (-F) and an oxa group (-O-), an alkenyl group having 2 to 12 carbon atoms including a fluoro group (-F) and an oxa group (-O-), an alkynyl group having 2 to 12 carbon atoms including a fluoro group (-F) and an oxa group (-O-), a fluoro group (-F) and an oxa group (-O-) containing an alkyl group having 2 to 12 carbon atoms -O-) is an aromatic group having 6 to 12 carbon atoms, preferably a methyl group (-CH3), a trifluoromethyl group (-CF3), an ethyl group (-CH2CH3), a n-propyl group (-CH2CH2CH3), an isopropyl group (-CH(CH3)CH3), a n-butyl group (-CH2CH2CH2CH3), a tert-butyl group (-C(CH3)3), a 2,2,2-trifluoroethyl group (-CH2CF3), a phenyl group (-C6H5), a methylphenyl group (-CH2C6H5), a p-methyl Phenyl (-C6H4CH3), p-trifluoromethylphenyl (-C6H4CF3), p-methoxyphenyl (-C6H4OCH3), p-trifluoromethoxyphenyl (-C6H4OCF3), p-fluorophenyl (-C6H4F), p-chlorophenyl (-C6H4Cl), particularly preferably methyl (-CH3), trifluoromethyl (-CF3), ethyl (-CH2CH3), n-propyl (-CH2CH2CH3), isopropyl (-CH(CH3)CH3).

[0239] L 71 and L 72 represents a "single bond (-)" or an "oxa-group (-O-)", and L 71 and L 72 At least one of them is an oxa-group (-O-), but L is particularly preferred. 71 is a single bond and L 72 It is a combination of oxa- (-O-).

[0240] Specific examples of compound (VII) include the following compound (VII-1) and the following compound (VII-2).

[0241] [Chemical formula 16]

[0242]

[0243] In the case where the non-aqueous electrolyte of the present disclosure contains compound (VII) as additive B, from the viewpoint of more effectively obtaining the effect brought by the non-aqueous electrolyte of the present disclosure, the content of compound (VII) relative to the total amount of the non-aqueous electrolyte is usually 0.01% by mass to 5.0% by mass, preferably 0.03% by mass or more, more preferably 0.05% by mass or more, further preferably 0.1% by mass or more, particularly preferably 0.3% by mass or more, preferably 3.0% by mass or less, more preferably 2.0% by mass or less, further preferably 1.0% by mass or less, particularly preferably 0.9% by mass or less. In addition, it can also be set to 0.8% by mass or less, 0.6% by mass or less.

[0244] When the non-aqueous electrolyte of the present disclosure contains compound (VII) as additive B, from the viewpoint of more effectively obtaining the effect brought about by the non-aqueous electrolyte of the present disclosure, the mass ratio of additive A to compound (VII) (i.e., the ratio of the mass of additive A to the mass of compound (VII), obtained by dividing the mass of additive A by the mass of compound (VI); hereinafter also referred to as the mass ratio [additive A / compound (VII)]) is usually 0.05 to 0.5, preferably 0.06 or more, and preferably 0.45 or less. In addition, it can also be set to 0.08 or more, 0.09 or more, 0.1 or more, 0.2 or more, and can also be set to 0.4 or less, 0.3 or less.

[0245] (Compound (VIII))

[0246] Compound (VIII) is a compound represented by the following formula (VIII).

[0247] [Chemical formula 17]

[0248]

[0249] In formula (VIII),

[0250] R 81 Each independently represents a "fluoro group (-F)", a "chloro group (-Cl)", a "bromo group (-Br)", or an "iodo group (-I)",

[0251] k represents an integer of 1 to 6.

[0252] As R 81 , particularly preferably a fluorine group (-F).

[0253] k represents an integer of 1 to 6, and k is preferably 1, 2, or 3, more preferably 2 or 3, and particularly preferably 3.

[0254] Specific examples of compound (VIII) include the following compound (VIII-1).

[0255] [Chemical formula 18]

[0256]

[0257] In the case where the non-aqueous electrolyte of the present disclosure contains compound (VIII) as additive B, from the viewpoint of more effectively obtaining the effect brought by the non-aqueous electrolyte of the present disclosure, the content of compound (VIII) relative to the total amount of the non-aqueous electrolyte is usually 0.01% by mass to 5.0% by mass, preferably 0.03% by mass or more, more preferably 0.05% by mass or more, further preferably 0.1% by mass or more, particularly preferably 0.3% by mass or more, preferably 3.0% by mass or less, more preferably 2.0% by mass or less, further preferably 1.0% by mass or less, particularly preferably 0.9% by mass or less. In addition, it can also be set to 0.8% by mass or less, 0.6% by mass or less.

[0258] When the non-aqueous electrolyte of the present disclosure contains compound (VIII) as additive B, from the viewpoint of more effectively obtaining the effect brought about by the non-aqueous electrolyte of the present disclosure, the mass ratio of additive A to compound (VIII) (i.e., the ratio of the mass of additive A to the mass of compound (VIII), the ratio obtained by dividing the mass of additive A by the mass of compound (VI); hereinafter also referred to as the mass ratio [additive A / compound (VIII)]) is usually 0.05 to 0.5, preferably 0.06 or more, and preferably 0.45 or less. In addition, it can also be set to 0.08 or more, 0.09 or more, 0.1 or more, 0.2 or more, and can also be set to 0.4 or less, 0.3 or less.

[0259] <Non-aqueous solvent>

[0260] The non-aqueous electrolyte generally contains a non-aqueous solvent. As the non-aqueous solvent, various known non-aqueous solvents can be appropriately selected. The non-aqueous solvent may be only one kind or may be two or more kinds.

[0261] Examples of the nonaqueous solvent include cyclic carbonates, fluorinated cyclic carbonates, chain carbonates, fluorinated chain carbonates, aliphatic carboxylates, fluorinated aliphatic carboxylates, γ-lactones, fluorinated γ-lactones, cyclic ethers, fluorinated cyclic ethers, chain ethers, fluorinated chain ethers, nitriles, amides, lactams, nitromethane, nitroethane, sulfolane, trimethyl phosphate, dimethyl sulfoxide, and dimethyl sulfoxide phosphoric acid.

[0262] Examples of the cyclic carbonates include ethylene carbonate (EC), propylene carbonate (PC), and butylene carbonate (BC).

[0263] Examples of the fluorine-containing cyclic carbonates include fluoroethylene carbonate (FEC) and the like.

[0264] Examples of the chain carbonates include dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), methyl propyl carbonate (MPC), ethyl propyl carbonate (EPC), and dipropyl carbonate (DPC).

[0265] Examples of the aliphatic carboxylic acid esters include methyl formate, methyl acetate, methyl propionate, methyl butyrate, methyl isobutyrate, methyl trimethylbutyrate, ethyl formate, ethyl acetate, ethyl propionate, ethyl butyrate, ethyl isobutyrate, and ethyl trimethylbutyrate.

[0266] Examples of the γ-lactones include γ-butyrolactone and γ-valerolactone.

[0267] Examples of the cyclic ethers include tetrahydrofuran, 2-methyltetrahydrofuran, tetrahydropyran, 1,3-dioxolane, 4-methyl-1,3-dioxolane, 1,3-dioxane, and 1,4-dioxane.

[0268] Examples of the chain ethers include 1,2-ethoxyethane (DEE), ethoxymethoxyethane (EME), diethyl ether, 1,2-dimethoxyethane, and 1,2-dibutoxyethane.

[0269] Examples of the nitriles include acetonitrile, glutaronitrile, adiponitrile, methoxyacetonitrile, and 3-methoxypropionitrile.

[0270] Examples of the amides include N,N-dimethylformamide and the like.

[0271] Examples of the lactams include N-methylpyrrolidone, N-methyloxazolidinone, and N,N′-dimethylimidazolidinone.

[0272] The nonaqueous solvent preferably contains at least one selected from the group consisting of cyclic carbonates, fluorine-containing cyclic carbonates, chain carbonates, and fluorine-containing chain carbonates.

[0273] In this case, relative to the total amount of the nonaqueous solvent, the total ratio of cyclic carbonates, fluorinated cyclic carbonates, linear carbonates, and fluorinated linear carbonates is preferably 50% by mass or more and 100% by mass or less, more preferably 60% by mass or more and 100% by mass or less, and further preferably 80% by mass or more and 100% by mass or less.

[0274] The nonaqueous solvent preferably contains at least one selected from the group consisting of cyclic carbonates and chain carbonates.

[0275] In this case, relative to the total amount of the nonaqueous solvent, the total ratio shared by cyclic carbonates and linear carbonates in the nonaqueous solvent is preferably more than 50 mass % and less than 100 mass %, more preferably more than 60 mass % and less than 100 mass %, further preferably more than 80 mass % and less than 100 mass %.

[0276] The upper limit of the content of the nonaqueous solvent is preferably 99% by mass, preferably 97% by mass, and more preferably 90% by mass relative to the total amount of the nonaqueous electrolyte. The lower limit of the content of the nonaqueous solvent is preferably 60% by mass or more, and more preferably 70% by mass or more relative to the total amount of the nonaqueous electrolyte.

[0277] From the viewpoint of further improving the dissociation property of the electrolyte and the mobility of the ions, the intrinsic viscosity of the nonaqueous solvent is preferably 10.0 mPa·s or less at 25°C.

[0278] <Electrolytes>

[0279] The non-aqueous electrolyte generally contains an electrolyte.

[0280] The electrolyte preferably contains at least one of a lithium salt containing fluorine (hereinafter, sometimes referred to as a “fluorine-containing lithium salt”) and a lithium salt not containing fluorine.

[0281] Examples of the fluorine-containing lithium salt include inorganic acid anion salts and organic acid anion salts.

[0282] Examples of the inorganic acid anion salt include lithium hexafluorophosphate (LiPF6), lithium tetrafluoroborate (LiBF4), lithium hexafluoroarsenate (LiAsF6), and lithium hexafluorotantalate (LiTaF6).

[0283] Examples of organic acid anion salts include lithium trifluoromethanesulfonate (LiCF 3 SO 3 ) and the like.

[0284] Among them, lithium hexafluorophosphate (LiPF6) is more preferred as the fluorine-containing lithium salt.

[0285] Examples of fluorine-free lithium salts include lithium perchlorate (LiClO4), lithium tetrachloroaluminate (LiAlCl4), lithium decachlorodecaborate (Li2B 10 Cl 10 )wait.

[0286] When the electrolyte contains a fluorine-containing lithium salt, the content ratio of the fluorine-containing lithium salt relative to the total amount of the electrolyte is preferably 50 mass % to 100 mass %, more preferably 60 mass % to 100 mass %, further preferably 80 mass % to 100 mass %.

[0287] When the fluorine-containing lithium salt includes lithium hexafluorophosphate (LiPF6), the content ratio of lithium hexafluorophosphate (LiPF6) relative to the total amount of the electrolyte is preferably 50 mass % to 100 mass %, more preferably 60 mass % to 100 mass %, and further preferably 80 mass % to 100 mass %.

[0288] When the non-aqueous electrolyte contains an electrolyte, the concentration of the electrolyte in the non-aqueous electrolyte is preferably greater than 0.1 mol / L (M (Molar)), more preferably greater than 0.5 mol / L (M), preferably less than 6 mol / L (M), more preferably less than 3 mol / L (M), and further preferably less than 2 mol / L (M).

[0289] When the non-aqueous electrolyte contains lithium hexafluorophosphate (LiPF6), the concentration of lithium hexafluorophosphate (LiPF6) in the non-aqueous electrolyte is preferably above 0.1 mol / L (M (Molar)) and below 3 mol / L (M), and more preferably above 0.5 mol / L (M) and below 2 mol / L (M).

[0290] 〔Lithium secondary battery precursor〕

[0291] The lithium secondary battery precursor of the present disclosure has:

[0292] housing, and

[0293] The positive electrode, negative electrode, separator, and electrolyte are housed in the casing.

[0294] Here,

[0295] The positive electrode is a positive electrode that can absorb and release lithium ions.

[0296] The negative electrode is a negative electrode that can absorb and release lithium ions.

[0297] The electrolyte is a non-aqueous electrolyte of the present disclosure.

[0298] In the present disclosure, the lithium secondary battery precursor refers to a lithium secondary battery before charging and discharging are performed.

[0299] According to the lithium secondary battery precursor of the present disclosure, in a lithium secondary battery obtained by charging and discharging the lithium secondary battery precursor, the room-temperature resistance increase rate during high-temperature storage can be reduced.

[0300] <Housing>

[0301] The shape of the case is not particularly limited and can be appropriately selected according to the application of the lithium secondary battery precursor of the present disclosure.

[0302] Examples of the case include a case made of a laminate film and a case formed of a battery case and a battery case cover.

[0303] <Positive electrode>

[0304] The positive electrode is a positive electrode that can absorb and release lithium ions.

[0305] The positive electrode preferably contains at least one positive electrode active material capable of absorbing and releasing lithium ions.

[0306] The positive electrode preferably includes a positive electrode current collector and a positive electrode mixture material layer provided on at least a portion of the surface of the positive electrode current collector.

[0307] Examples of the material of the positive electrode current collector include metals and alloys.

[0308] In detail, as the material of the positive electrode collector, aluminum, nickel, stainless steel (SUS), copper, etc. can be cited. Among them, from the viewpoint of the balance between the height of conductivity and cost, aluminum is preferred. Here, "aluminum" refers to pure aluminum or aluminum alloy. As the positive electrode collector, aluminum foil is preferred. The material of the aluminum foil is not particularly limited, and A1085 material, A3003 material, etc. can be cited.

[0309] The positive electrode mixture material layer contains a positive electrode active material and a binder.

[0310] The positive electrode active material is not particularly limited as long as it is a material that can absorb and release lithium ions, and can be appropriately adjusted depending on the purpose of the lithium secondary battery precursor and the like.

[0311] As the positive electrode active material, for example, the first oxide, the second oxide, etc. can be cited. The first oxide uses lithium (Li) and nickel (Ni) as constituent metal elements. The second oxide contains Li, Ni, and at least one of the metal elements other than Li and Ni as a constituent metal element. As metal elements other than Li and Ni, for example, transition metal elements, typical metal elements, etc. can be cited. For the second oxide, it is preferred that as metal elements other than Li and Ni, it is preferably included in a proportion that is the same as Ni or less than Ni in terms of atomic number conversion. Metal elements other than Li and Ni can be, for example, at least one selected from the group consisting of Co, Mn, Al, Cr, Fe, V, Mg, Ca, Na, Ti, Zr, Nb, Mo, W, Cu, Zn, Ga, In, Sn, La and Ce. These positive electrode active materials can be used alone or in combination.

[0312] The positive electrode active material preferably includes a lithium-containing composite oxide (hereinafter sometimes referred to as “NCM”) represented by the following formula (P1). The lithium-containing composite oxide (P1) has advantages of high energy density per unit volume and excellent thermal stability.

[0313] LiNi a Co b Mn c O2…Formula (P1)

[0314] In formula (P1), a, b, and c are each independently greater than 0 and less than 1, and the total of a, b, and c is greater than or equal to 0.99 and less than or equal to 1.00.

[0315] As a specific example of NCM, LiNi 0.33 Co 0.33 Mn 0.33 O2、LiNi 0.5 Co 0.3 Mn 0.2 O2、LiNi 0.5 Co 0.2 Mn 0.3 O2、LiNi 0.6 Co 0.2 Mn 0.2 O2、LiNi 0.8 Co 0.1 Mn 0.1 O2, etc.

[0316] The positive electrode active material may include a lithium-containing composite oxide (hereinafter, sometimes referred to as “NCA”) represented by the following formula (P2).

[0317] Li t Ni 1-x-y Co x Al y O2…Formula (P2)

[0318] In formula (P2), t is 0.95 to 1.15, x is 0 to 0.3, y is 0.1 to 0.2, and the sum of x and y is less than 0.5.)

[0319] As a specific example of NCA, LiNi 0.8 Co 0.15 Al 0.05 O2, etc.

[0320] In the case where the positive electrode in the lithium secondary battery precursor of the present disclosure comprises a positive electrode collector and a positive electrode mixture material layer comprising a positive electrode active material and a binder, the content of the positive electrode active material in the positive electrode mixture material layer is preferably not less than 10 mass % and not more than 99.9 mass %, more preferably not less than 30 mass % and not more than 99.9 mass %, further preferably not less than 50 mass % and not more than 99 mass %, and particularly preferably not less than 70 mass % and not more than 99 mass %.

[0321] As a binder, for example, polyvinyl acetate, polymethyl methacrylate, nitrocellulose, fluororesin, rubber particles, etc. can be mentioned. As fluororesin, polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), vinylidene fluoride-hexafluoropropylene copolymer, etc. can be mentioned. As rubber particles, styrene-butadiene rubber particles, acrylonitrile rubber particles, etc. can be mentioned. Among them, from the viewpoint of improving the oxidation resistance of the positive electrode mixture material layer, fluororesin is preferably used. One binder can be used alone, and two or more can be used in combination as needed.

[0322] From the perspective of the simultaneous realization of the physical properties (e.g., electrolyte permeability, peel strength, etc.) of the positive electrode mixture material layer and the battery performance, relative to the total amount of the positive electrode mixture material layer, the content of the binder in the positive electrode mixture material layer is preferably 0.1% by mass or more and 6% by mass or less. If the content of the binder is 0.1% by mass or more, the adhesion between the positive electrode mixture material layer and the positive electrode collector and the adhesion between the positive electrode active material are further improved. If the content of the binder is 6% by mass or less, the amount of the positive electrode active material in the positive electrode mixture material layer can be made more, so the discharge capacity is further improved.

[0323] The positive electrode mixture material layer preferably contains a conductive auxiliary agent.

[0324] As the material of the conductive aid, known conductive aids can be used. As the known conductive aid, preferably a carbon material with conductivity. As the carbon material with conductivity, graphite, carbon black, conductive carbon fiber, fullerene, etc. can be mentioned. They can be used alone, or two or more can be used together. As conductive carbon fiber, carbon nanotubes, carbon nanofibers, carbon fibers, etc. can be mentioned. As graphite, for example, artificial graphite, natural graphite, etc. can be mentioned. As natural graphite, for example, flaky graphite, blocky graphite, earthy graphite, etc. can be mentioned.

[0325] The material of the conductive auxiliary agent can be a commercially available product. As commercially available products of carbon black, for example, TOKA BLACK#4300, #4400, #4500, #5500, etc. (Tokai Carbon Co., Ltd., furnace black), PRINTEX L, etc. (Degussa, furnace black), Raven7000, 5750, 5250, 5000ULTRAIII, 5000ULTRA, etc., Conductex SC ULTRA, Conductex 975ULTRA, etc., PUER BLACK100, 115, 205, etc. (Columbian, furnace black), #2350, #2400B, #2600B, #30050B, #3030B, #3230B, #3350B, #3400B, #5400B, etc. (Mitsubishi Chemical Corporation, furnace black), MONARCH 1400, 1300, 900, Vulcan XC-72R, Black Pearls 2000, LITX-50, LITX-200, etc. (manufactured by Cabot Corporation, furnace black), Ensaco 250G, Ensaco 260G, Ensaco 350G, Super-P (manufactured by TIMCAL), KETJEN BLACK EC-300J, EC-600JD (manufactured by Akzo), DENKA BLACK, DENKA BLACK HS-100, FX-35 (manufactured by Denka Corporation, acetylene black), etc.

[0326] The positive electrode mixture material layer may contain other components, such as thickeners, surfactants, dispersants, wetting agents, defoaming agents, and the like.

[0327] <Negative electrode>

[0328] The negative electrode is a negative electrode that can store and release lithium ions.

[0329] The negative electrode preferably contains at least one negative electrode active material capable of absorbing and releasing lithium ions.

[0330] The negative electrode preferably includes a negative electrode current collector and a negative electrode mixture material layer provided on at least a portion of the surface of the negative electrode current collector.

[0331] The material of the negative electrode current collector is not particularly limited, and any known material can be used, for example, a metal or an alloy. Specifically, the material of the negative electrode current collector includes aluminum, nickel, stainless steel (SUS), nickel-plated steel, copper, etc. Among them, copper is preferably used as the material of the negative electrode current collector from the viewpoint of processability. As the negative electrode current collector, copper foil is preferably used.

[0332] The negative electrode mixture material layer includes a negative electrode active material and a binder.

[0333] The negative electrode active material is not particularly limited as long as it is a material that can absorb and release lithium ions. The negative electrode active material is preferably selected from at least one of the group consisting of, for example, metallic lithium, lithium-containing alloys, metals or alloys that can be alloyed with lithium, oxides that can be doped and dedoped with lithium ions, transition metal nitrides that can be doped and dedoped with lithium ions, and carbon materials that can be doped and dedoped with lithium ions. Among them, the negative electrode active material is preferably a carbon material that can be doped and dedoped with lithium ions (hereinafter, also referred to as "carbon material").

[0334] Examples of the carbon material include carbon black, activated carbon, graphite materials, and amorphous carbon materials. One of these carbon materials may be used, or two or more of these may be mixed and used. The form of the carbon material is not particularly limited, and for example, fibrous, spherical, potato-like, flaky, and the like may be used. The particle size of the carbon material is not particularly limited, and is preferably 5 μm to 50 μm, and more preferably 20 μm to 30 μm.

[0335] Examples of the amorphous carbon material include hard carbon, coke, mesocarbon microbeads (MCMB) obtained by calcining at 1500° C. or lower, and mesophase pitch carbon fibers (MCF).

[0336] As graphite materials, natural graphite and artificial graphite can be cited. As artificial graphite, graphitized MCMB, graphitized MCF, etc. can be cited. The graphite material can contain boron. The graphite material can also be coated with metal or amorphous carbon. As the material of the metal coated with the graphite material, gold, platinum, silver, copper, tin, etc. can be cited. The graphite material can also be a mixture of amorphous carbon and graphite.

[0337] The negative electrode mixture material layer preferably contains a conductive aid. Examples of the conductive aid include the same conductive aids as those exemplified as the conductive aids that can be contained in the positive electrode mixture material layer.

[0338] The negative electrode mixture material layer may contain other components in addition to the above components. Examples of other components include thickeners, surfactants, dispersants, wetting agents, defoaming agents, and the like.

[0339] <Diaphragm>

[0340] As the separator, for example, a porous resin flat plate can be cited. As the material of the porous resin flat plate, resin, nonwoven fabric containing the resin, etc. can be cited. As the resin, polyethylene (PE), polypropylene (PP), polymethylpentene (PMP), polyester, cellulose, polyamide, etc. can be cited.

[0341] The separator is preferably a porous resin sheet of a single-layer or multi-layer structure. The porous resin sheet is mainly made of one or more polyolefin resins. The thickness of the separator is preferably 5 μm to 30 μm. The separator is preferably arranged between the positive electrode and the negative electrode.

[0342] <Specific example of lithium secondary battery precursor>

[0343] Figure 1 This is a schematic cross-sectional view showing a laminated lithium secondary battery precursor as an example of the lithium secondary battery precursor of the present disclosure.

[0344] like Figure 1 As shown, the lithium secondary battery precursor 1 is a stacked type battery precursor.

[0345] Specifically, in the lithium secondary battery precursor 1, the battery element 10 is sealed inside the external package 30. The external package 30 is formed of a laminate film. The positive electrode lead 21 and the negative electrode lead 22 are each attached to the battery element 10. The positive electrode lead 21 and the negative electrode lead 22 are each led out from the inside of the external package 30 toward the outside in opposite directions.

[0346] like Figure 1 As shown, the battery element 10 is formed by stacking a positive electrode 11, a separator 13, and a negative electrode 12. The positive electrode 11 is formed by forming a positive electrode mixture material layer 11B on both main surfaces of a positive electrode collector 11A. The negative electrode 12 is formed by forming a negative electrode mixture material layer 12B on both main surfaces of a negative electrode collector 12A. The positive electrode mixture material layer 11B formed on one main surface of the positive electrode collector 11A of the positive electrode 11 and the negative electrode mixture material layer 12B formed on one main surface of the negative electrode collector 12A of the negative electrode 12 adjacent to the positive electrode 11 are opposite to each other through the separator 13.

[0347] The non-aqueous electrolyte of the present disclosure is injected into the external package 30 of the lithium secondary battery precursor 1. The non-aqueous electrolyte of the present disclosure permeates into the positive electrode mixture material layer 11B, the separator 13, and the negative electrode mixture material layer 12B. In the lithium secondary battery precursor 1, a single battery layer 14 is formed by adjacent positive electrode mixture material layers 11B, separators 13, and negative electrode mixture material layers 12B. It should be noted that the positive electrode and the negative electrode can also be products formed by forming each active material layer on one side of each collector.

[0348] It should be noted that the lithium secondary battery precursor 1 is a laminated lithium secondary battery precursor, but the lithium secondary battery precursor of the present disclosure is not limited thereto, for example, it may also be a wound lithium secondary battery precursor. The wound lithium secondary battery precursor is formed by overlapping the positive electrode, the separator, the negative electrode, and the separator in this order and winding them in layers. The wound lithium secondary battery precursor includes a cylindrical lithium secondary battery precursor and a square lithium secondary battery precursor.

[0349] like Figure 1 As shown, in the lithium secondary battery precursor 1, the direction in which the positive electrode lead and the negative electrode lead protrude from the inside of the external package 30 to the outside is opposite to the external package 30, but the present disclosure is not limited thereto. For example, the direction in which the positive electrode lead and the negative electrode lead protrude from the inside of the external package 30 to the outside can also be the same direction as the external package 30.

[0350] As an example of a lithium secondary battery of the present disclosure described later, there can be mentioned a lithium secondary battery obtained by charging and discharging a lithium secondary battery precursor 1 .

[0351] Figure 2 This is a schematic cross-sectional view showing a button-type lithium secondary battery precursor as another example of the lithium secondary battery precursor of the present disclosure.

[0352] Figure 2 In the button-type lithium secondary battery precursor shown, a disc-shaped negative electrode 42, a separator 45 injected with a non-aqueous electrolyte, a disc-shaped positive electrode 41, and stainless steel or aluminum partition plates 47 and 48 used as needed are stacked in this order and stored between a positive electrode box 43 (hereinafter also referred to as a "battery box") and a sealing plate 44 (hereinafter also referred to as a "battery box cover"). The positive electrode box 43 and the sealing plate 44 are sealed by a gasket 46.

[0353] In this example, as the nonaqueous electrolyte injected into the separator 45 , the nonaqueous electrolyte of the present disclosure is used.

[0354] As an example of the lithium secondary battery of the present disclosure described later, there can be mentioned Figure 2 The button-type lithium secondary battery precursor shown is a lithium secondary battery obtained by charging and discharging.

[0355] [Lithium secondary battery and method for manufacturing the same]

[0356] The method for manufacturing a lithium secondary battery of the present disclosure includes the following steps:

[0357] a step of preparing the lithium secondary battery precursor of the present disclosure (hereinafter also referred to as a "preparation step"), and

[0358] The lithium secondary battery precursor is subjected to charging and discharging steps.

[0359] The lithium secondary battery of the present disclosure is a lithium secondary battery obtained by charging and discharging the lithium secondary battery precursor of the present disclosure described above.

[0360] According to the lithium secondary battery and the method for manufacturing the same of the present disclosure, the room-temperature resistance increase rate of the lithium secondary battery during high-temperature storage can be reduced.

[0361] The preparation step may be a step of simply preparing the lithium secondary battery precursor of the present disclosure manufactured in advance for use in the charge and discharge steps, or may be a step of manufacturing the lithium secondary battery precursor of the present disclosure.

[0362] The lithium secondary battery precursor is as described above.

[0363] In the step of performing charging and discharging, charging and discharging of the lithium secondary battery precursor can be performed according to a known method.

[0364] In this step, the lithium secondary battery precursor may be subjected to repeated cycles of charge and discharge.

[0365] As described above, by this charge and discharge, a SEI (Solid Electrolyte Interface) film is ideally formed on the surface of the positive electrode (especially the positive electrode active material) and / or the negative electrode (especially the negative electrode active material) in the lithium secondary battery precursor.

[0366] Regarding the step of performing charging and discharging, it is preferred that a combination of charging and discharging be performed once or more on the lithium secondary battery precursor in an environment of 25° C. to 70° C.

[0367] Example

[0368] Hereinafter, examples of the present disclosure will be described, but the present disclosure is not limited to the following examples.

[0369] Hereinafter, "%" means "mass %" unless otherwise specified.

[0370] [Example 1-1]

[0371] <Preparation of non-aqueous electrolyte>

[0372] Ethylene carbonate (hereinafter referred to as "EC"), dimethyl carbonate (hereinafter referred to as "DMC"), and ethyl methyl carbonate (hereinafter referred to as "EMC") were mixed at a volume ratio of EC:DMC:EMC=30:35:35 to obtain a mixed solvent as a non-aqueous solvent.

[0373] LiPF6 as an electrolyte is dissolved in the obtained mixed solvent so that the concentration in the finally obtained non-aqueous electrolyte solution becomes 1.2 mol / L, thereby obtaining an electrolyte solution (hereinafter also referred to as a "basic electrolyte solution").

[0374] 1,3-Propene sultone (i.e., compound (I-1)) as additive A and lithium difluorophosphate (i.e., compound (III-1)) as additive B were added to the obtained basic electrolyte in such a manner that the contents (mass %) relative to the total amount of the finally obtained non-aqueous electrolyte were the contents described in Table 1, thereby obtaining a non-aqueous electrolyte.

[0375] Here, compound (I-1) is a specific example of compound (I), and lithium difluorophosphate (ie, compound (III-1)) is a specific example of compound (III).

[0376] <Production of positive electrode>

[0377] LiNi as the positive electrode active material 0.5 Co 0.2 Mn 0.3 O2 (90 mass%), carbon black (2.5 mass%) and graphite (2.5 mass%) as conductive aids, and polyvinylidene fluoride (PVdF) (5 mass%) as a binder are mixed to obtain a mixture. The obtained mixture is dispersed in N-methylpyrrolidone solvent to obtain a positive electrode mixture material slurry.

[0378] As a positive electrode current collector, an aluminum foil having a thickness of 20 μm was prepared.

[0379] The obtained positive electrode mixture material slurry is applied on an aluminum foil, dried, and then rolled using a press to obtain a sheet-shaped positive electrode. The positive electrode is composed of a positive electrode current collector and a positive electrode active material layer.

[0380] <Production of negative electrode>

[0381] Graphite (96% by mass) as a negative electrode active material, carbon black (1% by mass) as a conductive aid, 1% by mass (in terms of solid content) of sodium carboxymethyl cellulose dispersed in pure water as a thickener, and 2% by mass (in terms of solid content) of styrene-butadiene rubber (SBR) dispersed in pure water as a binder are mixed to obtain a negative electrode mixture material slurry.

[0382] As a negative electrode current collector, a copper foil having a thickness of 10 μm was prepared.

[0383] The obtained negative electrode mixture material slurry is applied on a copper foil, dried, and then rolled using a press to obtain a sheet-shaped negative electrode. The negative electrode is composed of a negative electrode current collector and a negative electrode active material layer.

[0384] <Preparation of diaphragm>

[0385] As a separator, a porous polyethylene film was prepared.

[0386] <Preparation of lithium secondary battery precursor>

[0387] The negative electrode was punched out into a disk shape with a diameter of 14 mm, the positive electrode was punched out into a disk shape with a diameter of 13 mm, and the separator was punched out into a disk shape with a diameter of 17 mm. Thus, a button-shaped negative electrode, a button-shaped positive electrode, and a button-shaped separator were obtained.

[0388] The obtained button-shaped negative electrode, button-shaped separator, and button-shaped positive electrode were stacked in this order in a stainless steel battery case (size: 2032 size). Next, 20 μL of nonaqueous electrolyte was injected into the battery case to immerse the separator, positive electrode, and negative electrode in the nonaqueous electrolyte.

[0389] Next, an aluminum plate (thickness 1.2 mm, diameter 16 mm) and a spring were placed on the positive electrode, and the battery case cover was caulked via a polypropylene gasket to seal the battery.

[0390] Through the above method, we can obtain Figure 2 The coin-type lithium secondary battery precursor (i.e., the lithium secondary battery before charging and discharging) of the structure shown is as follows. The dimensions of the lithium secondary battery precursor are 20 mm in diameter and 3.2 mm in height.

[0391] <Manufacturing of lithium secondary batteries>

[0392] The lithium secondary battery precursor was charged to 4.2 V and discharged to 2.5 V three times in a temperature range of 25° C. to 70° C., thereby obtaining a lithium secondary battery.

[0393] <Determination of Initial Discharge Capacity>

[0394] The lithium secondary battery was charged to 4.2 V in a thermostatic chamber at 25° C., and then discharged to 2.5 V, and the discharge capacity [mAh] (hereinafter also referred to as “initial discharge capacity”) was measured.

[0395] <Measurement of Initial Resistance Value>

[0396] After the initial discharge capacity was measured, the lithium secondary battery was charged to 3.7V, and then the voltage drop caused by CC10s discharge at the discharge rate of 0.1C to 1.0C was measured in a constant temperature chamber at 25°C (= voltage before the start of discharge - voltage at 10 seconds after the start of discharge). Here, CC10s discharge refers to discharge for 10 seconds at a constant current. Based on the obtained voltage drop and current values ​​(i.e., current values ​​corresponding to the discharge rate of 0.1C to 1.0C), the DC resistance [Ω] was measured as the initial resistance value.

[0397] <Initial resistance (relative value)>

[0398] The relative value of the initial resistance value of Example 1-1 when the initial resistance value of Comparative Example 1-1 was taken as 100 was determined as the initial resistance (relative value) of Example 1-1 (see the following formula).

[0399] Initial resistance of Example 1-1 (relative value) = (initial resistance value of Example 1-1) / (initial resistance value of Comparative Example 1-1) × 100

[0400] [Examples 1-2 and 1-3, Comparative Examples 1-2 and 1-3]

[0401] Except having changed the content of additive A and / or additive B as shown in Table 1, the same operation as Example 1-1 was performed.

[0402] The results are shown in Table 1.

[0403] [Comparative Example 1-1]

[0404] The same operation as in Example 1-1 was carried out except that the additive A was not used.

[0405] The results are shown in Table 1.

[0406] [Example 2-1]

[0407] The same operation as in Example 1-1 was performed except that the type of additive B was changed as shown in Table 1 and the initial resistance (relative value) was determined with the initial resistance value of Comparative Example 2-1 described later being 100.

[0408] The results are shown in Table 1.

[0409] The structure of the compound (II-1) as the additive B is as described above.

[0410] [Examples 2-2 and 2-3, Comparative Examples 2-2 and 2-3]

[0411] Except having changed the content of additive A and / or additive B as shown in Table 1, the same operation as Example 2-1 was performed.

[0412] The results are shown in Table 1.

[0413] [Comparative Example 2-1]

[0414] The same operation as in Example 2-1 was carried out except that the additive A was not used.

[0415] The results are shown in Table 1.

[0416] [Example 3-1]

[0417] The same operation as in Example 1-1 was performed except that the type of additive B was changed as shown in Table 1 and the initial resistance (relative value) was determined with the initial resistance value of Comparative Example 3-1 described later being 100.

[0418] The results are shown in Table 1.

[0419] The structure of the compound (II-2) as the additive B is as described above.

[0420] [Examples 3-2 and 3-3, Comparative Examples 3-2 and 3-3]

[0421] Except having changed the content of additive A and / or additive B as shown in Table 1, the same operation as Example 3-1 was performed.

[0422] The results are shown in Table 1.

[0423] [Comparative Example 3-1]

[0424] The same operation as in Example 3-1 was carried out except that the additive A was not used.

[0425] The results are shown in Table 1.

[0426] [Example 4-1]

[0427] The same operation as in Example 1-1 was performed except that the type of additive B was changed as shown in Table 1 and the initial resistance (relative value) was determined with the initial resistance value of Comparative Example 4-1 described later being 100.

[0428] The results are shown in Table 1.

[0429] The structure of the compound (IV-1) as the additive B is as described above.

[0430] [Examples 4-2 and 4-3, Comparative Examples 4-2 and 4-3]

[0431] Except having changed the content of additive A and / or additive B as shown in Table 1, the same operation as Example 4-1 was performed.

[0432] The results are shown in Table 1.

[0433] [Comparative Example 4-1]

[0434] The same operation as in Example 4-1 was carried out except that the additive A was not used.

[0435] The results are shown in Table 1.

[0436] [Table 1]

[0437]

[0438] [Chemical formula 19]

[0439]

[0440] [Example 5-1]

[0441] The same operation as in Example 1-1 was performed except that the type of additive B was changed as shown in Table 2 and the initial resistance (relative value) was determined with the initial resistance value of Comparative Example 5-1 described later being 100.

[0442] The results are shown in Table 2.

[0443] The structure of the compound (V-1) as the additive B is as described above.

[0444] [Examples 5-2 and 5-3, Comparative Examples 5-2 and 5-3]

[0445] Except having changed the content of additive A and / or additive B as shown in Table 2, the same operation as Example 5-1 was performed.

[0446] The results are shown in Table 2.

[0447] [Comparative Example 5-1]

[0448] The same operation as in Example 5-1 was carried out except that the additive A was not used.

[0449] The results are shown in Table 2.

[0450] [Example 6-1]

[0451] The same operation as in Example 1-1 was performed except that the type of additive B was changed as shown in Table 2 and the initial resistance (relative value) was determined with the initial resistance value of Comparative Example 6-1 described later being 100.

[0452] The results are shown in Table 2.

[0453] The structure of the compound (V-2) as the additive B is as described above.

[0454] [Examples 6-2 and 6-3, Comparative Examples 6-2 and 6-3]

[0455] Except having changed the content of additive A and / or additive B as shown in Table 2, the same operation as Example 6-1 was performed.

[0456] The results are shown in Table 2.

[0457] [Comparative Example 6-1]

[0458] The same operation as in Example 6-1 was carried out except that the additive A was not used.

[0459] The results are shown in Table 2.

[0460] [Example 7-1]

[0461] The same operation as in Example 1-1 was performed except that the type of additive B was changed as shown in Table 2 and the initial resistance (relative value) was determined with the initial resistance value of Comparative Example 7-1 described later being 100.

[0462] The results are shown in Table 2.

[0463] The structure of the compound (VI-2) as the additive B is as described above.

[0464] [Examples 7-2 and 7-3, Comparative Examples 7-2 and 7-3]

[0465] Except having changed the content of additive A and / or additive B as shown in Table 2, the same operation as Example 7-1 was performed.

[0466] The results are shown in Table 2.

[0467] [Comparative Example 7-1]

[0468] The same operation as in Example 7-1 was carried out except that the additive A was not used.

[0469] The results are shown in Table 2.

[0470] [Example 8-1]

[0471] The same operation as in Example 1-1 was performed except that the type of additive B was changed as shown in Table 2 and the initial resistance (relative value) was determined with the initial resistance value of Comparative Example 8-1 described later being 100.

[0472] The results are shown in Table 2.

[0473] The structure of the compound (VII-1) as the additive B is as described above.

[0474] [Examples 8-2 and 8-3, Comparative Examples 8-2 and 8-3]

[0475] Except having changed the content of additive A and / or additive B as shown in Table 2, the same operation as Example 8-1 was performed.

[0476] The results are shown in Table 2.

[0477] [Comparative Example 8-1]

[0478] The same operation as in Example 8-1 was carried out except that the additive A was not used.

[0479] The results are shown in Table 2.

[0480] [Example 9-1]

[0481] The same operation as in Example 1-1 was performed except that the type of additive B was changed as shown in Table 2 and the initial resistance (relative value) was determined with the initial resistance value of Comparative Example 9-1 described later being 100.

[0482] The results are shown in Table 2.

[0483] The structure of the compound (VIII-1) as the additive B is as described above.

[0484] [Examples 9-2 and 9-3, Comparative Examples 9-2 and 9-3]

[0485] Except having changed the content of additive A and / or additive B as shown in Table 2, the same operation as Example 9-1 was performed.

[0486] The results are shown in Table 2.

[0487] [Comparative Example 9-1]

[0488] The same operation as in Example 9-1 was carried out except that the additive A was not used.

[0489] The results are shown in Table 2.

[0490] [Table 2]

[0491]

[0492] [Chemical formula 20]

[0493]

[0494] [Example 10-1]

[0495] LiPF6 as an electrolyte is dissolved in a manner such that the concentration in the final non-aqueous electrolyte becomes 1.0 mol / L, and the compound (V-1) equivalent to the additive B is further dissolved in a manner such that the concentration in the final non-aqueous electrolyte becomes 0.2 mol / L. To the obtained basic electrolyte, the compound (I-1) as the additive A is added so that the content relative to the total amount of the final non-aqueous electrolyte becomes the content (mass %) recorded in Table 3. As the initial resistance (relative value), the relative value when the initial resistance value of the comparative example 10-1 described later is taken as 100 is calculated. Except for this, the same operation as in Example 1-1 is performed.

[0496] The results are shown in Table 3.

[0497] The structure of the compound (V-1) as the additive B is as described above.

[0498] [Examples 10-2 and 10-3, Comparative Examples 10-2 and 10-3]

[0499] Except having changed the content of additive A and / or additive B as shown in Table 3, the same operation as Example 10-1 was performed.

[0500] The results are shown in Table 3.

[0501] [Comparative Example 10-1]

[0502] The same operation as in Example 10-1 was carried out except that the additive A was not used.

[0503] The results are shown in Table 3.

[0504] [Example 11-1]

[0505] The same operation as in Example 1-1 was performed except that the type of additive B used as the electrolyte was changed as shown in Table 3 and the initial resistance (relative value) was determined with the initial resistance value of Comparative Example 11-1 described later being 100.

[0506] The results are shown in Table 3.

[0507] The structure of the compound (V-2) as the additive B is as described above.

[0508] [Examples 11-2 and 11-3, Comparative Examples 11-2 and 11-3]

[0509] Except having changed the content of additive A and / or additive B as shown in Table 3, the same operation as Example 11-1 was performed.

[0510] The results are shown in Table 3.

[0511] [Comparative Example 11-1]

[0512] The same operation as in Example 11-1 was carried out except that the additive A was not used.

[0513] The results are shown in Table 3.

[0514] [Table 3]

[0515]

[0516] As shown in Tables 1 to 3, in each of the Examples using a non-aqueous electrolyte for a battery containing an additive A as compound (I) and an additive B as an additive other than additive A, wherein the content of additive A is greater than 0.01 mass % and less than 0.5 mass % relative to the total amount of the non-aqueous electrolyte for a battery, the initial resistance of the battery can be reduced as compared with the comparative example in which additive A is not used, the comparative example in which the content of additive A is 0.01 mass %, and the comparative example in which the content of additive A is 0.5 mass %.

[0517] (Explanation of Reference Numerals)

[0518] 1Lithium secondary battery precursor

[0519] 10Battery Components

[0520] 11 Positive electrode

[0521] 11A Positive electrode collector

[0522] 11B Positive electrode mixture material layer

[0523] 12 Negative electrode

[0524] 12A Negative electrode collector

[0525] 12B Negative electrode mixture material layer

[0526] 13 Diaphragm

[0527] 14 single cell layers

[0528] 21 Positive wire

[0529] 22 Negative wire

[0530] 30 External package

[0531] 41 Positive electrode

[0532] 42 Negative electrode

[0533] 43 Positive electrode box

[0534] 44 Sealing plate

[0535] 45 Diaphragm

[0536] 46 Gasket

[0537] 47, 48 partition board

[0538] The entire disclosure of Japanese Patent Application No. 2022-143268 filed on September 8, 2022 is incorporated into this specification by reference.

[0539] All documents, patent applications, and technical standards described in this specification are incorporated into this specification by reference to the same extent as if each document, patent application, and technical standard was specifically and individually described.

Claims

1. A non-aqueous electrolyte for a battery, comprising: Additive A, wherein the additive A is a compound (I) represented by the following formula (I); and An additive B, wherein the additive B is at least one selected from the group consisting of a compound (II) represented by the following formula (II), a compound (III) that is at least one of a monofluorophosphate and a difluorophosphate, a compound (IV) represented by the following formula (IV), a compound (V) represented by the following formula (V), a compound (VI) represented by the following formula (VI), a compound (VII) represented by the following formula (VII), and a compound (VIII) represented by the following formula (VIII), The content of the additive A is greater than 0.01 mass % and less than 0.5 mass % relative to the total amount of the non-aqueous electrolyte for the battery. [Chemical formula 1] In formula (I), R 11 Each independently represents a fluoro group (—F), a hydrocarbon group having 1 to 8 carbon atoms which may contain a fluoro group (—F) as a substituent, or a carbon fluoro group having 1 to 8 carbon atoms, and h represents an integer of 0 to 4; [Chemical formula 2] In formula (II), R 21 represents a group represented by formula (ii-1), a group represented by formula (ii-2), or a divalent hydrocarbon group having 3 to 6 carbon atoms, * indicates the bonding position, In formula (ii-1), R 22 represents an oxymethylene group (-OCH2-), an oxyethylene group (-OCH2CH2-), an oxa-group (-O-), or a divalent hydrocarbon group having 1 to 6 carbon atoms, In formula (ii-2), R 23 represents a hydrocarbon group having 1 to 8 carbon atoms; In formula (IV), M 41+ represents an alkali metal ion, X 41 each independently represents a fluoro group (-F), a chloro group (-Cl), a bromo group (-Br), or an iodo group (-I), Y 41 represents a boron atom or a phosphorus atom, R 41 each independently represents a single bond (-) or a divalent hydrocarbon group having 1 to 6 carbon atoms which may contain at least one group selected from the group consisting of a fluoro group (-F), a chloro group (-Cl), a bromo group (-Br), and an iodo group (-I) as a substituent, i in Y 41 When it is a boron atom, it represents 1 or 2. 41 When it is a phosphorus atom, it represents an integer of 1 to 3, j in the Y 41 When it is a boron atom, it represents 0 or 2. 41 When it is a phosphorus atom, it represents 0, 2, or 4; In formula (V), M 51+ represents an alkali metal ion, R 51 and R 52 Each independently represents a fluoro group (—F), a hydrocarbon group having 1 to 3 carbon atoms which may contain a fluoro group as a substituent, or a fluorocarbon group having 1 to 3 carbon atoms; In formula (VI), R 61 represents a hydrocarbon group having 1 to 8 carbon atoms which may contain at least one group selected from the group consisting of a fluoro group (-F), a chloro group (-Cl), a bromo group (-Br), an iodo group (-I), an oxa-group (-O-), a thiol group (-S-), a secondary amino group (-NH-), a tertiary amino group (-N<), a carbonyl group (>C=O), and a sulfonyl group (>S(=O)2) as a substituent, L 61 Represents a single bond (-) or an oxa-group (-O-); In formula (VII), M 71+ represents an alkali metal ion, R 71 and R 72 each independently represents a fluoro group (-F), a chloro group (-Cl), a bromo group (-Br), an iodo group (-I), a hydrocarbon group having 1 to 12 carbon atoms which may contain at least one group selected from the group consisting of a fluoro group (-F), a chloro group (-Cl), a bromo group (-Br), an iodo group (-I), and an oxa group (-O-) as a substituent, or a fluorocarbon group having 1 to 8 carbon atoms, L 71 and L 72 represents a single bond (-) or an oxa-group (-O-), and L 71 and L 72 At least one of them is an oxa-group (-O-); In formula (VIII), R 81 each independently represents a fluoro group (-F), a chloro group (-Cl), a bromo group (-Br), or an iodo group (-I), k represents an integer of 1 to 6.

2. The non-aqueous electrolyte for a battery according to claim 1, wherein The content mass ratio of the additive A to the additive B (content mass of the additive A / content mass of the additive B) is 0.05 to 0.

5.

3. The non-aqueous electrolyte for a battery according to claim 1, wherein The content of the additive A is 0.05 mass % to 0.4 mass % relative to the total amount of the non-aqueous electrolyte for the battery.

4. The non-aqueous electrolyte for a battery according to claim 1, wherein The content of the additive B is 0.01 mass % to 5.0 mass % relative to the total amount of the non-aqueous electrolyte for the battery.

5. The non-aqueous electrolyte for a battery according to claim 1, comprising the compound (II) as the additive B, The content of the additive B is 0.01 mass % to 5.0 mass % relative to the total amount of the non-aqueous electrolyte for the battery.

6. The non-aqueous electrolyte for a battery according to claim 1, comprising the compound (III) as the additive B, The content mass ratio of the additive A to the additive B (content mass of the additive A / content mass of the additive B) is 0.05 to 0.

4.

7. The non-aqueous electrolyte for a battery according to claim 1, comprising the compound (IV) as the additive B, The content of the additive B is 0.01 mass % to 5.0 mass % relative to the total amount of the non-aqueous electrolyte for the battery.

8. The non-aqueous electrolyte for a battery according to claim 1, comprising the compound (V) as the additive B, The content of the additive B is 0.1 mol / L to 6 mol / L relative to the total amount of the non-aqueous electrolyte for the battery.

9. A lithium secondary battery precursor comprising: housing, and A positive electrode, a negative electrode, a separator, and an electrolyte contained in the housing; The positive electrode is a positive electrode that can absorb and release lithium ions. The negative electrode is a negative electrode that can absorb and release lithium ions. The electrolyte solution is the non-aqueous electrolyte solution for a battery according to any one of claims 1 to 8.

10. The lithium secondary battery precursor according to claim 9, wherein The positive electrode comprises a lithium-containing composite oxide represented by the following formula (P1) as a positive electrode active material, LiNi a Co b Mn c O2…Formula (P1) In formula (P1), a, b, and c are each independently greater than 0 and less than 1, and the total of a, b, and c is greater than or equal to 0.99 and less than or equal to 1.

00.

11. A method for manufacturing a lithium secondary battery, comprising the following steps: A step of preparing the lithium secondary battery precursor according to claim 9, and The lithium secondary battery precursor is subjected to charging and discharging steps.

12. A lithium secondary battery obtained by charging and discharging the lithium secondary battery precursor according to claim 9.

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