Non-aqueous electrolyte and non-aqueous electrolyte battery containing the non-aqueous electrolyte

Abstract

To provide a non-aqueous electrolyte that can provide a non-aqueous electrolyte battery with excellent discharge power capacity and high reliability. [Solution] A non-aqueous electrolyte is provided containing an electrolyte, a non-aqueous solvent, a compound represented by general formula (1), and a compound represented by general formula (α). TIFF2026143597000020.tif25159 TIFF2026143597000021.tif35162

Description

[Technical Field]

[0001] The present invention relates to a non-aqueous electrolyte and a non-aqueous electrolyte battery containing the non-aqueous electrolyte. [Background technology]

[0002] Non-aqueous electrolyte batteries, such as lithium-ion secondary batteries, are being put into practical use in a wide range of applications, from so-called consumer power supplies for mobile phones and laptops to on-board power supplies for automobiles. However, in recent years, the demand for higher performance in non-aqueous electrolyte batteries has been increasing, and improvements in various battery characteristics, particularly high capacity, low-temperature operation characteristics, high-temperature storage characteristics, and cycle characteristics, are being sought.

[0003] To date, numerous technologies have been investigated regarding various battery components, including the active materials of the positive and negative electrodes, and the non-aqueous electrolyte, as means of improving various battery characteristics such as the capacity of non-aqueous electrolyte batteries.

[0004] For example, Patent Document 1 discloses a lithium secondary battery comprising a specific positive electrode, a negative electrode, and an electrolyte disposed between the positive and negative electrodes, wherein the electrolyte contains a specific amount of a lithium salt, a non-aqueous solvent, and a specific disilane compound. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] U.S. Patent Application Publication No. 2018 / 212281 [Overview of the initiative] [Problems that the invention aims to solve]

[0006] Non-aqueous electrolyte batteries typically have a battery current cutoff mechanism to prevent overcharging, from a safety standpoint. Some battery current cutoff mechanisms activate when they detect gas generation during overcharging.

[0007] The inventors focused on the amount of gas generated in non-aqueous electrolyte batteries and conducted thorough research. They found that the difference between the amount of gas generated due to causes other than overcharging, such as high temperature, and the amount of gas generated during overcharging is relatively large. This allows for the proper detection of gas generation during overcharging while suppressing false detection of gas generation due to causes other than overcharging, thereby enabling the battery current cutoff mechanism to operate appropriately and improving the reliability of the battery.

[0008] Based on these findings, we examined the technology described in Patent Document 1 and found that there is room to increase the difference between the amount of gas generated due to causes other than overcharging and the amount of gas generated during overcharging, and therefore there is room to improve the reliability of the battery.

[0009] The present invention aims to provide a non-aqueous electrolyte that can provide a non-aqueous electrolyte battery with excellent discharge power capacity and high reliability. [Means for solving the problem]

[0010] In view of the above circumstances, the inventors conducted diligent studies and found that the above objective can be achieved by using a compound represented by general formula (1), described later, and a compound represented by general formula (α), described later, in combination, and thus completed the present invention. A non-aqueous electrolyte battery manufactured using the non-aqueous electrolyte of the present invention can suppress malfunctions of the battery's current interruption valve and improve its discharge power capacity. While its operation and principle are not entirely clear, they are presumed to be as follows. However, the present invention is not limited to the operation and principle described below. If the compound represented by general formula (1) has a highly electrophilic substructure (e.g., Si-H or Si-Ph), it undergoes a nucleophilic substitution reaction on the silicon atom with nucleophilic components (e.g., Li2CO3, LiF, etc.) contained in the positive electrode active material. As a result, a protective film is formed on the positive electrode surface, preventing other electrolyte components from coming into contact with the positive electrode surface and suppressing the oxidative decomposition reaction of the electrolyte. On the other hand, when the battery becomes overcharged and the positive electrode potential becomes higher than the normal operating potential, this protective film component undergoes oxidative decomposition, causing gas generation. Here, it is conceivable that by appropriately setting the pressure of the current cutoff valve, malfunctions of the current cutoff valve during normal use can be suppressed while still activating the current cutoff valve in the event of abnormalities such as overcharging. However, the compound represented by the general formula (1) is highly reactive at the negative electrode and is therefore more easily decomposed at the negative electrode than it is at the positive electrode. For this reason, even if only the compound represented by the general formula (1) is added to the electrolyte, it will hardly act appropriately on the positive electrode and will not effectively suppress malfunctions of the battery's current cutoff valve. On the other hand, compounds represented by general formula (α) are susceptible to reductive decomposition on the negative electrode surface due to their amide structure. The negative electrode protective film formed by reductive decomposition is in a very stable form, which can suppress the continuous decomposition of the electrolyte. Therefore, by using the compound represented by general formula (1) and the compound represented by general formula (α) in combination, the decomposition and consumption of the compound represented by general formula (1) at the negative electrode is suppressed, and it can act effectively on the positive electrode. As a result, gas generation can be caused when the battery is overcharged, while gas generation during normal use can be suppressed. Furthermore, since the compound represented by general formula (1) has the effect of suppressing the interfacial resistance of the positive electrode, and the compound represented by general formula (α) has the effect of suppressing the interfacial resistance of the negative electrode, it is presumed that the discharge power capacity can be improved by using each of them in combination.

[0011] In other words, the gist of this invention is as follows:

[0012] [1] A non-aqueous electrolyte solution containing an electrolyte, a non-aqueous solvent, a compound represented by the following general formula (1), and a compound represented by the following general formula (α).

Chemical Formula

Chemical Formula

[10] A non-aqueous electrolyte according to any one of [1] to [9], wherein the content of the compound represented by general formula (1) is 0.001 to 10% by mass relative to the total amount of the non-aqueous electrolyte.

[11] A non-aqueous electrolyte according to any one of [1] to

[10] , wherein the content of the compound represented by general formula (α) is 0.001 to 10% by mass relative to the total amount of the non-aqueous electrolyte.

[12] A non-aqueous electrolyte according to any one of [1] to

[11] , wherein the electrolyte contains lithium hexafluorophosphate, and the ratio of the content of hexafluorophosphate anions to the total content of the compound represented by general formula (α) and the compound represented by general formula (1) in the non-aqueous electrolyte is 50 to 30,000 by mass.

[13] A non-aqueous electrolyte battery comprising a positive electrode, a negative electrode, and a non-aqueous electrolyte, A non-aqueous electrolyte battery, wherein the non-aqueous electrolyte is a non-aqueous electrolyte described in any of [1] to

[12] . [Effects of the Invention]

[0013] According to the present invention, it is possible to provide a non-aqueous electrolyte that can give a non-aqueous electrolyte battery with excellent discharge power capacity and high reliability. [Modes for carrying out the invention]

[0014] In this specification, "α~β" or "α-β" means a numerical range of α or greater and β or less. n " means that the number of carbon atoms is n. A "hydrocarbon group" means a group consisting of carbon and hydrogen that is linear or branched. A "heteroatom" refers to an atom other than carbon and hydrogen atoms, such as an oxygen atom, sulfur atom, silicon atom, or halogen atom. A "hydrocarbon group which may be substituted with heteroatoms" means an unsubstituted hydrocarbon group, a hydrocarbon group in which any hydrogen atom is substituted with a halogen atom, or a hydrocarbon group in which any atom is substituted with a functional group containing a heteroatom other than a halogen atom. A "hydrocarbon group which may be substituted with halogen atoms" means an unsubstituted hydrocarbon group or a hydrocarbon group in which any hydrogen atom is substituted with a halogen atom. An "aliphatic unsaturated hydrocarbon group" means an aliphatic hydrocarbon group having at least one carbon-carbon unsaturated bond. An "organic group" means a group having at least one carbon atom. An "alkenyl group" means an aliphatic hydrocarbon group having at least one carbon-carbon double bond. An "alkynyl group" means an aliphatic hydrocarbon group having at least one carbon-carbon triple bond.

[0015] [1. Non-aqueous electrolyte] A non-aqueous electrolyte according to one embodiment of the present invention contains an electrolyte, a non-aqueous solvent, a compound represented by the following general formula (1), and a compound represented by the following general formula (α). The components are described below.

[0016] [1-1. Compounds represented by general formula (1)] A non-aqueous electrolyte according to one embodiment of the present invention contains a compound represented by the following general formula (1).

[0017] [ka] (In general formula (1), R a R represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, which may have substituents; x , R y and R z Each of these independently comprises a hydrogen atom, a hydrocarbon group having 1 to 12 carbon atoms which may have substituents, or -SiR 1 R 2 R 3 The silyl group represented by R is shown; 1 ~R 3 Each of these independently represents a hydrocarbon group having 1 to 12 carbon atoms, which may be substituted with a hydrogen atom or a halogen atom.

[0018] One compound represented by general formula (1) may be used, or two or more compounds may be used. Hereinafter, R a , R x , R y and R z This will explain the following.

[0019] (R a ) In general formula (1), R a This represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, which may have substituents.

[0020] R a Specific examples of hydrocarbon groups involved include alkyl groups, alkenyl groups, alkynyl groups, and aryl groups. Specific examples of alkyl groups include methyl group, ethyl group, n-propyl group, iso-propyl group, n-butyl group, tert-butyl group, n-pentyl group, hexyl group, heptyl group, octyl group, nonyl group, and decyl group. Among these, methyl group, ethyl group, n-propyl group, n-butyl group, tert-butyl group, n-pentyl group, and hexyl group are preferred, and more preferably methyl group, ethyl group, n-propyl group, n-butyl group, tert-butyl group, and n-pentyl group are preferred, and particularly preferably methyl group, ethyl group, n-butyl group, and tert-butyl group. Specific examples of alkenyl groups include vinyl, allyl, methallyl, 2-butenyl, 3-methyl-2-butenyl, 3-butenyl, and 4-pentenyl groups. Preferably, vinyl, allyl, methallyl, and 2-butenyl groups are used; more preferably, vinyl, allyl, and methallyl groups are used; and most preferably, vinyl and allyl groups are used. Specific examples of alkynyl groups include ethynyl group, 2-propynyl group, 2-butynyl group, 3-butynyl group, 4-pentynyl group, and 5-hexynyl group. Among these, ethynyl group, 2-propynyl group, 2-butynyl group, and 3-butynyl group are preferred, more preferably 2-propynyl group and 3-butynyl group, and most preferably 2-propynyl group. Specific examples of aryl groups include phenyl, tolyl, benzyl, and phenethyl groups. Among these, the phenyl group is preferred.

[0021] R a This may be a hydrocarbon group having 1 to 12 carbon atoms with substituents, or it may be a hydrocarbon group having 1 to 12 carbon atoms without substituents. Here, R a The substituents involved include cyano groups, isocyanato groups, and acyl groups (-(C=O)-R s ), acyloxy group (-O(C=O)-R s ), alkoxycarbonyl group (-(C=O)OR s ), sulfonyl group (-SO2-R s ), sulfonyloxy group (-O(SO2)-R s), an alkoxysulfonyl group (-(SO2)-O-R s ), an alkoxysulfonyloxy group (-O-(SO2)-O-R s ), an alkoxycarbonyloxy group (-O-(C=O)-O-R s ), an ether group (-O-R s ), an acrylic group, a methacrylic group, halogen atoms such as a fluorine atom, a chlorine atom and a bromine atom (preferably a fluorine atom), a trifluoromethyl group, and the like. In addition, R s represents an alkyl group having 1 to 10 carbon atoms, an alkylene group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, or an alkynyl group having 2 to 10 carbon atoms. R s when being an alkylene group, may bind to a part of a substituted hydrocarbon group to form a ring. Among these substituents, preferred are a cyano group, an isocyanato group, an acyloxy group (-O(C=O)-R s ), a halogen atom (preferably a fluorine atom), and a trifluoromethyl group; more preferred are an isocyanato group, an acyloxy group (-O(C=O)-R s ), a halogen atom (preferably a fluorine atom), and a trifluoromethyl group; particularly preferred are an acyloxy group (-O(C=O)-R s ), a halogen atom (preferably a fluorine atom), and a trifluoromethyl group; and most preferred is a halogen atom (preferably a fluorine atom).

[0022] From the viewpoint of further enhancing the action and effect of the compound represented by general formula (1), R a is preferably a hydrocarbon group having 1 to 12 carbon atoms which may be substituted with a hydrogen atom or a halogen atom, more preferably a hydrogen atom or an (unsubstituted) hydrocarbon group having 1 to 12 carbon atoms, still more preferably a hydrogen atom, an unsubstituted alkyl group having 1 to 12 carbon atoms, or an unsubstituted aryl group having 6 to 12 carbon atoms, and particularly preferably a hydrogen atom, a methyl group, or a phenyl group.

[0023] In addition, R aThe number of carbon atoms in the hydrocarbon group is not particularly limited, but can be 1 to 12. However, from the viewpoint of further enhancing the effects of the compound represented by general formula (1), it is preferably 1 to 6, more preferably 1 to 4, even more preferably 1 to 3, particularly preferably 1 to 2, and most preferably 1. Here, if the hydrocarbon group has substituents, the number of carbon atoms in the substituents is not included in this carbon number.

[0024] (R x , R y , R z ) In general formula (1), R x , R y and R z Each of these independently comprises a hydrogen atom, a hydrocarbon group having 1 to 12 carbon atoms which may have substituents, or -SiR 1 R 2 R 3 This represents a silyl group represented by R. x , R y and R z They may be the same or different.

[0025] R x , R y and R z The hydrocarbon group involved is R a Examples of hydrocarbon groups related to this can be those similar to those described above, with alkyl groups and aryl groups being preferred. R x , R y and R z Preferably, alkyl groups include methyl, ethyl, n-propyl, n-butyl, tert-butyl, n-pentyl, and hexyl groups; more preferably, methyl, ethyl, n-propyl, n-butyl, tert-butyl, and n-pentyl groups; and most preferably, methyl, ethyl, n-butyl, and tert-butyl groups. R x , R y and R z Preferably, the aryl group involved is a phenyl group.

[0026] Rx , R y and R z Each of these may independently be a hydrocarbon group having 1 to 12 carbon atoms with substituents, or an unsubstituted hydrocarbon group having 1 to 12 carbon atoms. x , R y and R z The substituents relating to this include R a The substituents related to this can be the same as those mentioned above, and the preferred substituents are also the same.

[0027] R x , R y and R z Each of these is independently -SiR 1 R 2 R 3 It may also be a silyl group represented by . Here, R 1 ~R 3 Each of these independently represents a hydrocarbon group having 1 to 12 carbon atoms, which may be substituted with a hydrogen atom or a halogen atom. 1 R 2 R 3 In the silyl group represented by R 1 ~R 3 These may be the same or different, but from the viewpoint of facilitating the synthesis of the compound, it is preferable that at least two are the same.

[0028] R 1 ~R 3 The hydrocarbon group involved is R x , R y and R z Examples of hydrocarbon groups related to this can be the same as those mentioned above, and the same applies to preferred groups.

[0029] R 1 ~R 3 Each of these may independently be a hydrocarbon group having 1 to 12 carbon atoms substituted with a halogen atom, or an unsubstituted hydrocarbon group having 1 to 12 carbon atoms. Here, examples of halogen atoms include fluorine atoms, chlorine atoms, bromine atoms, etc., with fluorine atoms being preferred.

[0030] From the viewpoint of further enhancing the effects of compounds represented by general formula (1), R 1 ~R 3 Each of them operates independently. It is preferably a hydrocarbon group having 1 to 12 carbon atoms, which may be substituted with halogen atoms. It is more preferably a C1-C12 alkyl group which may be substituted with a halogen atom, or a C1-C12 aryl group which may be substituted with a halogen atom. It is more preferably a C1-C6 alkyl group which may be substituted with a halogen atom, or a phenyl group which may be substituted with a halogen atom. It is particularly preferable that the alkyl group having 1 to 4 carbon atoms may be substituted with a halogen atom, or that the phenyl group may be substituted with a halogen atom. Most preferably, it is a C1-C2 alkyl group which may be substituted with a halogen atom, or a phenyl group which may be substituted with a halogen atom.

[0031] From the viewpoint of further enhancing the effects of compounds represented by general formula (1), -SiR 1 R 2 R 3 In the silyl group represented by R 1 ~R 3 It is preferable that one or more (preferably two or more) of these are C1-C12 alkyl groups that may be substituted with halogen atoms. In addition, in a certain manner, R 1 ~R 3 However, it is also preferable that each of them be an alkyl group having 1 to 12 carbon atoms, which may be substituted with a halogen atom.

[0032] Note, R 1 ~R 3 The number of carbon atoms in each hydrocarbon group is not particularly limited, but from the viewpoint of further enhancing the effects of the compound represented by general formula (1), it is preferably 1 to 10, more preferably 1 to 8, and even more preferably 1 to 6. 1 ~R 3If the hydrocarbon group is an alkyl group, the number of carbon atoms in each alkyl group may be 1 to 12 independently and is not particularly limited, but is preferably 1 to 10, more preferably 1 to 8, even more preferably 1 to 6, especially preferably 1 to 4, particularly preferably 1 to 2, and most preferably 1.

[0033] R x , R y and R z Each is independently a hydrocarbon group having 1 to 12 carbon atoms, which may have substituents, or -SiR 1 R 2 R 3 It is preferable that the silyl group is represented by the following: A hydrocarbon group having 1 to 12 carbon atoms or -SiR which may be substituted with a halogen atom. 1 R 2 R 3 It is more preferable that the silyl group is represented by A C1-C12 alkyl group which may be substituted with a halogen atom, a C1-C12 aryl group which may be substituted with a halogen atom, or -SiR 1 R 2 R 3 It is more preferably a silyl group represented by, A C1-C6 alkyl group which may be substituted with a halogen atom, a phenyl group which may be substituted with a halogen atom, or -SiR 1 R 2 R 3 It is especially preferable that the silyl group is represented by, A C1-C4 alkyl group which may be substituted with a halogen atom, a phenyl group which may be substituted with a halogen atom, or -SiR 1 R 2 R 3 It is particularly preferable that the silyl group is represented by the following: A C1-C2 alkyl group which may be substituted with a halogen atom, a phenyl group which may be substituted with a halogen atom, or -SiR 1 R 2 R 3 It is most preferable that the silyl group is represented by .

[0034] From the viewpoint of further enhancing the effects of compounds represented by general formula (1), R in general formula (1) x , R y and R z One or more of these (preferably two or more) -SiR 1 R 2 R 3 It is preferable that the silyl group is represented by the following: -SiR 1a R 2a R 3a (R 1a ~R 3a Each of these independently represents a hydrocarbon group having 1 to 12 carbon atoms, which may be substituted with a halogen atom. More preferably, it is a silyl group represented by ). -SiR 1b R 2b R 3b (R 1b ~R 3b Each independently represents a C1-C12 alkyl group that may be substituted with a halogen atom, or a C1-C12 aryl group that may be substituted with a halogen atom. More preferably, it is a silyl group represented by ). -SiR 1c R 2c R 3c (R 1c ~R 3c Each of these independently represents an alkyl group having 1 to 12 carbon atoms, which may be substituted with a halogen atom. A silyl group represented by ( is particularly preferred.)

[0035] Note, R x , R y and R z The number of carbon atoms in each hydrocarbon group is not particularly limited, but from the viewpoint of further enhancing the effects of the compound represented by general formula (1), it is preferably 1 to 10, more preferably 1 to 8, and even more preferably 1 to 6. x , R y and R zIf the hydrocarbon group is an alkyl group, the number of carbon atoms in each alkyl group may be 1 to 12 independently, and is not particularly limited, but is preferably 1 to 10, more preferably 1 to 8, even more preferably 1 to 6, especially preferably 1 to 4, particularly preferably 1 to 2, and most preferably 1. Here, if the hydrocarbon group has substituents, the number of carbon atoms in the substituents is not included in this carbon number.

[0036] (Molecular weight of compounds represented by general formula (1)) The molecular weight of the compound represented by general formula (1) is not particularly limited, but from the viewpoint of further enhancing the effects of the compound represented by general formula (1), it is preferably 80 to 1000, more preferably 120 to 600, even more preferably 160 to 400, and particularly preferably 200 to 300.

[0037] (Content of the compound represented by general formula (1)) The content of the compound represented by general formula (1) is not particularly limited, but from the viewpoint of further enhancing the effects of the compound represented by general formula (1), it is preferably 0.001 to 10% by mass, more preferably 0.001 to 8% by mass, even more preferably 0.001 to 6% by mass, particularly preferably 0.001 to 4% by mass, and most preferably 0.01 to 4% by mass, relative to the total amount of the non-aqueous electrolyte.

[0038] The identification and measurement of the content of compounds represented by general formula (1) in non-aqueous electrolytes are performed by nuclear magnetic resonance (NMR) spectroscopy.

[0039] [1-2. Compounds represented by general formula (α)] A non-aqueous electrolyte according to one embodiment of the present invention contains, in addition to the compound represented by the above general formula (1), a compound represented by the following general formula (α).

[0040] [ka]

[0041] (In general formula (α), R 89is a hydrogen atom or -SiR 8 R 9 R 10 The silyl group represented by R is shown; 8 ~R 10 Each of these independently represents a hydrogen atom, a halogen atom, a C1-C12 hydrocarbon group which may have substituents, or a C1-C12 alkoxy group which may have substituents; R 11 This is a hydrogen atom, a hydrocarbon group having 1 to 12 carbon atoms which may have substituents, or -SiR d R e R f The silyl group represented by R is shown; d , R e and R f Each independently represents a hydrogen atom, a halogen atom, an optionally substituted C1-C12 hydrocarbon group, or an optionally substituted C1-C12 alkoxy group; Y represents a hydrogen atom, a halogen atom, an optionally substituted C1-C12 hydrocarbon group, an optionally substituted C1-C12 alkoxy group, -NR g -SiR h R i R j A base represented by -NR g -H is a group denoted by R g R represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, which may have substituents; h , R i and R j Each of these independently represents a hydrogen atom, a halogen atom, a C1-C12 hydrocarbon group which may have substituents, or a C1-C12 alkoxy group which may have substituents. 11 and R g They may be bonded to each other, forming a ring.

[0042] One compound represented by general formula (α) may be used, or two or more compounds may be used. Hereinafter, R 89 , R 8 ~R 11 , R g We will explain , and Y, etc.

[0043] (R89 ) R related to general formula (α) 89 is a hydrogen atom or -SiR 8 R 9 R 10 The silyl group represented by R 8 ~R 10 Each of these independently represents a hydrogen atom, a halogen atom, a C1-C12 hydrocarbon group which may have substituents, or a C1-C12 alkoxy group which may have substituents.

[0044] R 89 Examples of halogen atoms involved include fluorine atoms, chlorine atoms, and bromine atoms, and fluorine atoms are preferred from the viewpoint of minimizing electrochemical side reactions.

[0045] R 89 Specific examples of hydrocarbon groups involved include alkyl groups, alkenyl groups, alkynyl groups, aralkyl groups, and aryl groups. Specific examples of alkyl groups include methyl group, ethyl group, n-propyl group, iso-propyl group, n-butyl group, tert-butyl group, n-pentyl group, hexyl group, heptyl group, octyl group, nonyl group, and decyl group. Preferably, methyl group, ethyl group, n-propyl group, n-butyl group, tert-butyl group, n-pentyl group, and hexyl group; more preferably, methyl group, ethyl group, n-propyl group, n-butyl group, tert-butyl group, and n-pentyl group; and especially preferably, methyl group, ethyl group, n-butyl group, and tert-butyl group. The above alkyl groups are preferred because the compound represented by general formula (α) tends to localize near the surface of the positive electrode active material and / or negative electrode active material. Specific examples of alkenyl groups include vinyl groups, allyl groups, methallyl groups, 2-butenyl groups, 3-methyl-2-butenyl groups, 3-butenyl groups, and 4-pentenyl groups. Among these, vinyl groups, allyl groups, methallyl groups, and 2-butenyl groups are preferred, more preferably vinyl groups, allyl groups, and methallyl groups, and particularly preferably vinyl groups or allyl groups. The above-mentioned alkenyl groups are preferred because they tend to localize the compound represented by general formula (α) near the surface of the positive electrode active material and / or negative electrode active material. Specific examples of alkynyl groups include ethynyl group, 2-propynyl group, 2-butynyl group, 3-butynyl group, 4-pentynyl group, and 5-hexynyl group. Among these, ethynyl group, 2-propynyl group, 2-butynyl group, and 3-butynyl group are preferred, more preferably 2-propynyl group and 3-butynyl group, and particularly preferably 2-propynyl group. The above-mentioned alkynyl groups are preferred because they tend to localize the compound represented by general formula (α) near the surface of the positive electrode active material and / or negative electrode active material. Specific examples of aryl groups include phenyl groups and tolyl groups. Among these, the phenyl group is preferred from the viewpoint that the compound represented by general formula (α) tends to localize near the surface of the positive electrode active material and / or negative electrode active material. Specific examples of aralkyl groups include the benzyl group and the phenethyl group.

[0046] Specific examples of alkoxy groups having 1 to 12 carbon atoms include methoxy, ethoxy, propoxy, butoxy, and isopropoxy groups. Among these, alkoxy groups having 1 to 6 carbon atoms are preferred, alkoxy groups having 1 to 4 carbon atoms are more preferred, and methoxy and ethoxy groups are even more preferred, from the viewpoint of minimizing steric hindrance of the compound and allowing it to be suitably concentrated on the active material surface.

[0047] R 8 ~R 10 The hydrocarbon group and alkoxy group relating to this may each independently have substituents or may not have substituents. Here, R 8 ~R10 The substituents involved include cyano groups, isocyanato groups, and acyl groups (-(C=O)-R s ), acyloxy group (-O(C=O)-R s ), alkoxycarbonyl group (-(C=O)OR s ), sulfonyl group (-SO2-R s ), sulfonyloxy group (-O(SO2)-R s ), alkoxysulfonyl group (-(SO2)-OR s ), alkoxysulfonyl oxy group (-O-(SO2)-OR s ), alkoxycarbonyloxy group (-O-(C=O)-OR s ), ether group (-OR s Examples include acrylic groups, methacrylic groups, halogen atoms such as fluorine atoms, chlorine atoms, and bromine atoms (preferably fluorine atoms), and trifluoromethyl groups. s R represents an alkyl group having 1 to 10 carbon atoms, an alkylene group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, or an alkynyl group having 2 to 10 carbon atoms. s If it is an alkylene group, it may bond with some of the substituted hydrocarbon groups to form a ring. Among these substituents, cyano groups, isocyanate groups, and acyloxy groups (-O(C=O)-R s ), halogen atom (preferably a fluorine atom), trifluoromethyl group, and more preferably isocyanate group, acyloxy group (-O(C=O)-R s ), halogen atom (preferably a fluorine atom), trifluoromethyl group, and particularly preferably an acyloxy group (-O(C=O)-R s ), halogen atom (preferably a fluorine atom), and trifluoromethyl group.

[0048] R 8 ~R 10Preferably, each of these is independently a C1-C12 hydrocarbon group that may have substituents and a C1-C12 alkoxy group that may have substituents, more preferably a C1-C12 hydrocarbon group that may have substituents, and even more preferably an alkyl group that may have substituents. Furthermore, from the viewpoint that compounds related to general formula (α) tend to be suitably localized on the electrode surface, R 8 ~R 10 Preferably, at least one of them is an alkyl group having 1 to 12 carbon atoms, and more preferably, at least two of them are alkyl groups having 1 to 12 carbon atoms. 8 ~R 10 It is even more preferable that all of them are alkyl groups having 1 to 12 carbon atoms.

[0049] Note, R 8 ~R 10 The number of carbon atoms in each hydrocarbon group is not particularly limited, but is preferably 1 to 6, more preferably 1 to 4, even more preferably 1 to 2, and most preferably 1. Here, if the hydrocarbon group has substituents, the number of carbon atoms in the substituents is not included in this carbon number.

[0050] -SiR 8 R 9 R 10 In the silyl group represented by R 8 ~R 10 These may be the same or different, but it is preferable that at least two are the same in terms of facilitating the synthesis of the compound, and it is even more preferable from the above-mentioned viewpoint that all three are the same.

[0051] (R 11 ) R related to general formula (α) 11 This is a hydrogen atom, a hydrocarbon group having 1 to 12 carbon atoms which may have substituents, or -SiR d R e R f This represents a silyl group.

[0052] R11 As for the hydrocarbon group having 1 to 12 carbon atoms that may have substituents, R 8 ~R 10 The same items mentioned above can be cited, and the same applies to preferred options.

[0053] -SiR d R e R f R in the silyl group represented by d ~R f Each of these independently represents a hydrogen atom, a halogen atom, a C1-C12 hydrocarbon group which may have substituents, or a C1-C12 alkoxy group which may have substituents. Here, R is an example of a halogen atom, a C1-C12 hydrocarbon group which may have substituents, and a C1-C12 alkoxy group which may have substituents. 8 ~R 10 The same items mentioned above can be cited, and the same applies to preferred options.

[0054] Note, R d ~R f The number of carbon atoms in each hydrocarbon group is not particularly limited, but is preferably 1 to 6, more preferably 1 to 4, even more preferably 1 to 2, and most preferably 1. Here, if the hydrocarbon group has substituents, the number of carbon atoms in the substituents is not included in this carbon number.

[0055] R 11 Preferably, the hydrocarbon group is a hydrogen atom and a C1-C12 hydrocarbon group which may have substituents; more preferably, a hydrogen atom and an (unsubstituted) C1-C12 hydrocarbon group; even more preferably, a hydrogen atom and a C1-C6 hydrocarbon group; particularly preferably, a hydrogen atom and a C1-C4 hydrocarbon group; and most preferably, a hydrogen atom and an alkyl group which has C1-C4.

[0056] Note, R 11The number of carbon atoms in each hydrocarbon group is not particularly limited, but is preferably 1 to 6, more preferably 1 to 4, even more preferably 1 to 2, and most preferably 1. Here, if the hydrocarbon group has substituents, the number of carbon atoms in the substituents is not included in this carbon number.

[0057] (Y) Y in general formula (α) is a hydrogen atom, a halogen atom, a C1-C12 hydrocarbon group which may have substituents, a C1-C12 alkoxy group which may have substituents, -NR g -SiR h R i R j A base represented by -NR g -H represents the group, R g R represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, which may have substituents. h , R i and R j Each of these independently represents a hydrogen atom, a halogen atom, a C1-C12 hydrocarbon group which may have substituents, or a C1-C12 alkoxy group which may have substituents.

[0058] Here, the halogen atom related to Y, the C1-C12 hydrocarbon group which may have substituents, and the C1-C12 alkoxy group which may have substituents are R 8 ~R 10 The same items mentioned above can be cited, and the same applies to preferred options.

[0059] -NR g -SiR h R i R j In a base represented by R g R is a hydrocarbon group having 1 to 12 carbon atoms, which may have a hydrogen atom or a substituent. Here, the hydrocarbon group having 1 to 12 carbon atoms, which may have a substituent, is R 11 It is synonymous with what is defined by, and the same applies to preferred terms. Also, -SiR h R i R jThe group represented by -SiR d R e R f This is synonymous with the base represented by , and the same applies to preferred bases.

[0060] -NR g In a group represented by -H, R g R is a hydrocarbon group having 1 to 12 carbon atoms, which may have a hydrogen atom or a substituent. Here, the hydrocarbon group having 1 to 12 carbon atoms, which may have a substituent, is R 11 This is equivalent to what is defined in -NR. g In a group represented by -H, R g Preferably, the hydrocarbon group consists of a hydrogen atom and an (unsubstituted) hydrocarbon group having 1 to 12 carbon atoms; more preferably, a hydrogen atom and a hydrocarbon group having 1 to 6 carbon atoms; and even more preferably, a hydrogen atom and a hydrocarbon group having 1 to 4 carbon atoms. Y is -NR g -SiR h R i R j The base represented by -NR g It is preferable that the group is represented by -H, or a hydrocarbon group having 1 to 12 carbon atoms, which may have substituents.

[0061] The compound represented by general formula (α) is preferably the compound represented by general formula (α1) or the compound represented by general formula (α2). (Compounds represented by the general formula (α1))

[0062] [ka]

[0063] (In general formula (α1), R 8 ~R 10 Each of these independently represents a hydrogen atom, a halogen atom, a C1-C12 hydrocarbon group which may have substituents, or a C1-C12 alkoxy group which may have substituents. 11 This is a hydrogen atom, a hydrocarbon group having 1 to 12 carbon atoms which may have substituents, or -SiR d R e Rf This represents a silyl group represented by R. d , R e and R f Each independently represents a hydrogen atom, a halogen atom, an optionally substituted C1-C12 hydrocarbon group, or an optionally substituted C1-C12 alkoxy group. Y' represents a hydrogen atom, a halogen atom, an optionally substituted C1-C12 hydrocarbon group, an optionally substituted C1-C12 alkoxy group, or -NR g -SiR h R i R j This indicates the group represented by R. g R represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, which may have substituents. h , R i and R j Each of these independently represents a hydrogen atom, a halogen atom, a C1-C12 hydrocarbon group which may have substituents, or a C1-C12 alkoxy group which may have substituents. 11 and R g They may be bonded to each other, forming a ring.

[0064] In the general formula (α1), R 8 ~R 11 , R d , R e , R f , R g , R h , R i and R j R in general formula (α) 8 ~R 11 , R d , R e , R f , R g , R h , R i and R j Corresponding to each, Y' in general formula (α1) is a hydrogen atom, a halogen atom, a C1-C12 hydrocarbon group which may have substituents, a C1-C12 alkoxy group which may have substituents, or -NR g -SiR h R i Rj This corresponds to the base represented by .

[0065] Specific examples of compounds having a Si-N structure represented by the general formula (α1) include compounds with the following structures.

[0066] [ka]

[0067] Preferably, the following compounds are mentioned.

[0068] [ka]

[0069] More preferably, the following compounds are mentioned.

[0070] [ka]

[0071] Particularly preferred are the following compounds.

[0072] [ka]

[0073] (Compounds represented by the general formula (α2))

[0074] [ka]

[0075] (In general formula (α2), R 111 '' represents a hydrogen atom or a C1-C12 hydrocarbon group which may have substituents. Y'' represents a hydrogen atom, a halogen atom, a C1-C12 hydrocarbon group which may have substituents, a C1-C12 alkoxy group which may have substituents, or -NRg R indicates a group represented by -H. g (This represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, which may have substituents.)

[0076] R in the general formula (α2) 111 R in general formula (α) 11 Of these, R in general formula (α2) corresponds to a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms which may have substituents. g R in general formula (α) g Correspondingly, Y'' in general formula (α2) is a hydrogen atom, a halogen atom, a C1-C12 hydrocarbon group which may have substituents, a C1-C12 alkoxy group which may have substituents, or -NR g Corresponds to the group represented by -H. R related to general formula (α2) 111 Preferably, the hydrocarbon group is a hydrogen atom and a C1-C12 hydrocarbon group which may have substituents; more preferably, a hydrogen atom and an (unsubstituted) C1-C12 hydrocarbon group; even more preferably, a hydrogen atom and a C1-C6 hydrocarbon group; particularly preferably, a hydrogen atom and a C1-C4 hydrocarbon group; and most preferably, a hydrogen atom and an alkyl group which has C1-C4.

[0077] Specific examples of compounds represented by the general formula (α2) include compounds with the following structures.

[0078] [ka]

[0079] The following compounds are preferred as examples of compounds represented by the general formula (α2).

[0080] [ka]

[0081] More preferably, the following compounds are included as compounds represented by the general formula (α2).

[0082]

Chem.

[0083] As the compound represented by general formula (α2), the following compounds are particularly preferably mentioned.

[0084]

Chem.

[0085] (Content of the compound represented by general formula (α)) The content of the compound represented by general formula (α) is not particularly limited, but from the viewpoint of further enhancing the action and effect of the compound represented by general formula (α), it is preferably 0.001 to 10% by mass, more preferably 0.001 to 8% by mass, still more preferably 0.001 to 6% by mass, particularly preferably 0.001 to 4% by mass, and most preferably 0.01 to 4% by mass, relative to the total amount of the non-aqueous electrolyte solution. When the total content of the compound represented by general formula (α) relative to the total amount of the non-aqueous electrolyte solution falls within the above range, concentration of the compound represented by general formula (α) in the active material proceeds suitably, making it possible to produce a battery with less gas generation during initial conditioning.

[0086] (Ratio of the content of the compound represented by general formula (1) to the content of the compound represented by general formula (α)) The ratio of the content of the compound represented by general formula (1) to the content of the compound represented by general formula (α) in the non-aqueous electrolyte solution is not particularly limited. On a mass basis, it is preferably 0.1 or more, more preferably 0.2 or more, still more preferably 0.4 or more, particularly preferably 0.8 or more; on the other hand, it is preferably 1000 or less, more preferably 500 or less, still more preferably 300 or less, and particularly preferably 100 or less.

[0087] Identification of the compound represented by general formula (α) and measurement of its content in the non-aqueous electrolyte solution are performed by nuclear magnetic resonance (NMR) spectroscopy. Furthermore, there are no particular limitations on the method of incorporating the compound represented by general formula (α) and the compound represented by general formula (1) into the electrolyte. In addition to the method of directly adding the above compounds to the electrolyte, there are also methods of generating the above compounds inside the battery or in the electrolyte.

[0088] In this specification, the compound content refers to the content at the time of manufacturing the non-aqueous electrolyte, at the time the non-aqueous electrolyte is injected into the battery, or at any of the following points in time when the battery is shipped.

[0089] [1-3. Electrolytes] The electrolyte contained in the non-aqueous electrolyte is usually an alkali metal salt and is not particularly limited, but a lithium salt is preferred. Since the electrolyte is in a dissociated state in the electrolyte, it is sufficient if an anion is detected. The electrolyte is preferably free from phosphate anions having an FP=O bond, alkyl sulfate anions, fluorosulfonic acid anions, and oxalate complex anions. Examples of lithium salts as electrolytes include lithium fluoroborate salts such as LiBF4; lithium fluorophosphate salts such as LiPF6; lithium sulfonate salts such as CH3SO3Li and CF3SO3Li; lithium imide salts such as LiN(CF3SO2)2, LiN(C2F5SO2)2, lithium cyclic 1,2-perfluoroethanedisulfonylimide, and lithium cyclic 1,3-perfluoropropanedisulfonylimide; lithium methide salts such as LiC(C2F5SO2)3; lithium tungstate salts; lithium carboxylate salts; fluorine-containing organic lithium salts; and the like.

[0090] Among these, the electrolyte is LiPF6, LiBF4, and LiN(C) M F 2M+1 SO2)(C N F 2N+1 At least one electrolyte selected from the group consisting of SO2)(0≦M≦4, 0≦N≦4) is preferred, and LiPF6 is more preferred.

[0091] The combination of two or more electrolytes is not particularly limited, but combinations of LiPF6 and LiN(FSO2)2; LiPF6 and LiN(CF3SO2)2; LiPF6 and LiBF4; LiBF4 and LiN(FSO2)2; and LiBF4, LiPF6, and LiN(FSO2)2 are preferred. Among these, combinations of LiPF6 and LiN(FSO2)2; LiPF6 and LiBF4; and LiBF4, LiPF6, and LiN(FSO2)2 are more preferred.

[0092] (Electrolyte content) The electrolyte content is typically 0.001 to 18% by mass relative to the total volume of the non-aqueous electrolyte, preferably 0.01 to 18% by mass, more preferably 0.1 to 18% by mass, more preferably 1 to 18% by mass, more preferably 3 to 18% by mass, more preferably 5 to 18% by mass, more preferably 8 to 18% by mass, more preferably 8.5 to 18% by mass, and more preferably 9 to 18% by mass. Within this range, the effects can be further enhanced.

[0093] (Ratio of hexafluorophosphate anion content to content of compound represented by general formula (1)) The non-aqueous electrolyte preferably contains hexafluorophosphate anions. In this case, the ratio of the content of hexafluorophosphate anions [g] to the content of the compound represented by general formula (1) [g] (content of hexafluorophosphate anions / content of the compound represented by general formula (1)) is not particularly limited, but is preferably 100 to 60000, more preferably 200 to 20000, and even more preferably 400 to 6000.

[0094] (Ratio of hexafluorophosphate anion content to content of compound represented by general formula (α)) When the non-aqueous electrolyte contains hexafluorophosphate anions, the ratio of the content of hexafluorophosphate anions [g] to the content of the compound represented by general formula (α) [g] (content of hexafluorophosphate anions / content of the compound represented by general formula (α)) is not particularly limited, but is preferably 100 to 60000, more preferably 200 to 20000, and even more preferably 400 to 6000.

[0095] (Ratio of hexafluorophosphate anion content to the total content of compounds represented by general formula (α) and general formula (1)) When the non-aqueous electrolyte contains hexafluorophosphate anions, the ratio of the content of hexafluorophosphate anions [g] to the total content [g] of the compound represented by general formula (α) and the compound represented by general formula (1) (content of hexafluorophosphate anions / total content of the compound represented by general formula (α) and the compound represented by general formula (1)) is not particularly limited, but is preferably 50 to 30,000, more preferably 100 to 10,000, and even more preferably 200 to 3,000.

[0096] [1-4. Non-aqueous solvents] The non-aqueous solvent of the non-aqueous electrolyte is not particularly limited as long as it dissolves the electrolyte, and any known non-aqueous solvent can be used. The non-aqueous solvent may be, for example, saturated cyclic carbonates such as ethylene carbonate, propylene carbonate, and butylene carbonate; linear carbonates such as dimethyl carbonate, diethyl carbonate, di-n-propyl carbonate, diisopropyl carbonate, and ethyl methyl carbonate; linear carboxylic acid esters such as methyl acetate, ethyl acetate, propyl acetate, butyl acetate, and methyl propionate; cyclic carboxylic acid esters such as γ-butyrolactone and γ-valerolactone; ether compounds such as dimethoxymethane, diethoxymethane, tetrahydrofuran, 2-methyltetrahydrofuran, 1,4-dioxane, and 4-methyl-1,3-dioxane; sulfone compounds such as 2-methylsulfolane and dimethylsulfone; and so on.

[0097] Among these, at least one non-aqueous solvent selected from the group consisting of saturated cyclic carbonates, linear carbonates, and linear carboxylic acid esters is preferred, and saturated cyclic carbonates or linear carbonates are more preferred.

[0098] Examples of combinations of two or more non-aqueous solvents include combinations of saturated cyclic carbonates and linear carbonates, combinations of saturated cyclic carbonates and linear carboxylic acid esters, combinations of cyclic carboxylic acid esters and linear carbonates, and combinations of saturated cyclic carbonates, linear carbonates and linear carboxylic acid esters.

[0099] Among these, combinations of saturated cyclic carbonates and linear carbonates, as well as combinations of saturated cyclic carbonates, linear carbonates, and linear carboxylic acid esters, are preferred.

[0100] [1-5. Auxiliary Agents] A non-aqueous electrolyte according to one embodiment of the present invention may contain known auxiliary agents to the extent that it does not significantly impair the effects of the present invention.

[0101] The auxiliary agent is preferably at least one compound selected from the group consisting of cyclic carbonates having carbon-carbon unsaturated bonds, fluorine-containing cyclic carbonates, compounds having isocyanate groups, organic compounds having an isocyanuric acid skeleton, sulfur-containing organic compounds, phosphorus-containing organic compounds, organic compounds having cyano groups, silicon-containing compounds (excluding compounds represented by general formula (1) and compounds represented by general formula (α)), aromatic compounds, cyclic compounds having ether bonds, fluorine-free carboxylic acid esters, carboxylic acid anhydrides, triple bond-containing compounds, phosphazene compounds, cyclic acetal compounds, borate anions, phosphate anions having FP=O bonds, and anions having S=O bonds. For example, compounds described in International Publication No. 2015 / 111676 are preferred. As the auxiliary agent, at least one compound selected from the group consisting of a phosphate anion having an F-P=O bond and an anion having an S=O bond (hereinafter also referred to as "specific anion") is more preferred, and it is more preferred to select at least one from phosphate anions having an F-P=O bond and at least one from anions having an S=O bond. Further, from the viewpoint of improving the suppression rate of malfunction of the battery current interrupt valve, it is preferable that the composition includes a cyclic carbonate having a carbon-carbon unsaturated bond and / or a fluorine-containing cyclic carbonate (hereinafter also referred to as "specific carbonate compound").

[0102] The content of the auxiliary agent is not particularly limited, and is arbitrary as long as the effects of the present invention are not significantly impaired. Based on the total amount of the non-aqueous electrolyte solution, the content is usually 0.001 to 10% by mass, preferably 0.001 to 8% by mass, more preferably 0.001 to 6% by mass, still more preferably 0.001 to 4% by mass, and particularly preferably 0.001 to 3% by mass. Within this range, the effect of the auxiliary agent can be further enhanced.

[0103] (Specific Anion) Among the auxiliary agents, at least one anion selected from a phosphate anion having an F-P=O bond, an alkyl sulfate anion, a fluorosulfonic acid anion, and an oxalate complex anion (hereinafter also referred to as "specific anion") is preferred from the viewpoint of easily forming a stable coating on an electrode.

[0104] Among the specific anions, difluorophosphate anions, fluorosulfonate anions, and bis(oxalato)borate anions are more preferred, and difluorophosphate anions and fluorosulfonate anions are even more preferred.

[0105] The specific anions are derived from acids or salts, and also include anions generated in the system. The specific anions are preferably contained in the non-aqueous electrolyte solution in the form of a salt. As counter cations, alkali metal cations such as lithium, sodium and potassium are preferred, and lithium cations are more preferred. The specific anions are described below.

[0106] (Content of specific anions) The content of specific anions (total amount if there are two or more) is usually 0.001 to 10% by mass, preferably 0.001 to 8% by mass, more preferably 0.001 to 6% by mass, even more preferably 0.001 to 4% by mass, and especially preferably 0.001 to 3% by mass, relative to the total amount of the non-aqueous electrolyte. Within this range, the effects can be further enhanced.

[0107] The identification and measurement of the content of specific anions are performed using nuclear magnetic resonance (NMR) spectroscopy.

[0108] [1-5-1. Phosphate anions with FP=O bonds] Phosphate anions having an FP=O bond include, for example, PO3F - Monofluorophosphate anions such as PO2F2 - Difluorophosphate anions such as; etc. The phosphate anion having the FP=O bond is preferably a monofluorophosphate anion and / or a difluorophosphate anion, and more preferably a difluorophosphate anion.

[0109] [1-5-2. Anions containing an S=O bond] Anions having an S=O bond are not particularly limited as long as they have at least one S=O bond in the molecule. For example, fluorosulfonic acid anion (FSO3 - ), alkyl sulfate anion (C l H 2l+1 OSO3 - ,1≦l≦10), alkyl halogenated sulfate anions, sulfonylmethide anions ((R 5 SO2)3C - ), or sulfonyliimide anion ((R 6 SO2)2N - )(R 5 or R 6 (These are hydrocarbon groups having 1 to 10 carbon atoms, and may be the same or different.) The anion having the S=O bond is preferably at least one selected from fluorosulfonic acid anions, alkyl sulfate anions, sulfonylmethide anions, and sulfonylimide anions. It is more preferable that the anion is at least one selected from fluorosulfonic acid anions and alkyl sulfate anions, and at least one selected from sulfonylimid anions. Fluorosulfonic acid anions and sulfonylimide anions are more preferable.

[0110] [1-5-2-1. Alkyl sulfate anion] Alkyl sulfate anions are not particularly limited as long as they are sulfate anions having an alkyl group with 1 to 10 carbon atoms. l H 2l+1 OSO3 - Anions represented by (1≦l≦10) are preferred, C l H 2l+1 OSO3 - Anions represented by (1 ≤ l ≤ 5) are more preferred, and methyl sulfate anions or ethyl sulfate anions are even more preferred.

[0111] [1-5-2-2. Sulfonylimide anion] Sulfonylimide anions are not particularly limited as long as they have a sulfonyl structure and an imide structure. Sulfonylimide anions are (R 6 SO2)2N - (R 6 (FSO2)2N is a preferred anion, which is a hydrocarbon group that may have a fluorine atom or a halogen atom, and may be the same or different. - An anion represented by is more preferable.

[0112] (Specific carbonates) From the viewpoint of improving the malfunction suppression rate of the battery current cutoff valve, it is preferable to include a cyclic carbonate having a carbon-carbon unsaturated bond and / or a fluorine-containing cyclic carbonate (hereinafter also referred to as "specific carbonate compound"), and it is preferable to include a cyclic carbonate having a carbon-carbon unsaturated bond and a fluorine-containing cyclic carbonate.

[0113] (Content of specific carbonates) The content of specific carbonates (total amount if there are two or more types) is usually 0.001 to 10% by mass, preferably 0.001 to 8% by mass, more preferably 0.001 to 6% by mass, even more preferably 0.001 to 4% by mass, and especially preferably 0.01 to 4% by mass, relative to the total amount of the non-aqueous electrolyte. Within this range, the effects can be further enhanced.

[0114] [1-5-3. Cyclic carbonates containing carbon-carbon unsaturated bonds] A cyclic carbonate having a carbon-carbon unsaturated bond (hereinafter also referred to as "unsaturated cyclic carbonate") is not particularly limited as long as it has a carbon-carbon double bond or a carbon-carbon triple bond. In this specification, cyclic carbonates having an aromatic ring are also included in the category of unsaturated cyclic carbonates. Examples of unsaturated cyclic carbonates include vinylene carbonates such as vinylene carbonate and vinylvinylene carbonate; and ethylene carbonates substituted with substituents having aromatic rings or carbon-carbon double or carbon-carbon triple bonds, such as vinylethylene carbonate, ethynylethylene carbonate, and phenylethylene carbonate. In particular, from the viewpoint of forming a stable interfacial protective film, vinylene carbonates are preferred, vinylethylene carbonate and ethynylethylene carbonate are more preferred, vinylene carbonate and vinylethylene carbonate are even more preferred, and vinylene carbonate is particularly preferred.

[0115] [1-5-4. Fluorine-containing cyclic carbonates] Fluorine-containing cyclic carbonates are not particularly limited as long as they have a cyclic carbonate structure and contain fluorine atoms. Examples of fluorine-containing cyclic carbonates include fluorinated cyclic carbonates having alkylene groups with 2 to 6 carbon atoms, and their derivatives. Examples include fluorinated ethylene carbonates (hereinafter sometimes referred to as "fluorinated ethylene carbonate") and their derivatives. Examples of derivatives of fluorinated ethylene carbonates include fluorinated ethylene carbonates substituted with alkyl groups (for example, alkyl groups with 1 to 4 carbon atoms). Among these, fluorinated ethylene carbonates with 1 to 8 fluorine atoms and their derivatives are preferred. Examples of fluorinated ethylene carbonates and their derivatives having 1 to 8 fluorines include monofluoroethylene carbonate, 4,4-difluoroethylene carbonate, 4,5-difluoroethylene carbonate, 4-fluoro-4-methylethylene carbonate, 4,5-difluoro-4-methylethylene carbonate, 4-fluoro-5-methylethylene carbonate, 4,4-difluoro-5-methylethylene carbonate, and 4-(fluoromethyl)-ethylene carbonate. In particular, from the viewpoint of providing high ionic conductivity to the electrolyte and forming a stable interfacial protective film, fluorinated ethylene carbonate with 1 to 8 fluorines is preferred, monofluoroethylene carbonate, 4,4-difluoroethylene carbonate, and 4,5-difluoroethylene carbonate are more preferred, and monofluoroethylene carbonate is even more preferred.

[0116] [2.Nonaqueous electrolyte battery] One embodiment of the present invention is a non-aqueous electrolyte battery comprising a positive electrode, a negative electrode, and a non-aqueous electrolyte. The non-aqueous electrolyte battery is preferably a non-aqueous electrolyte secondary battery. The non-aqueous electrolyte battery is usually constructed by housing the positive electrode, negative electrode, separator, and non-aqueous electrolyte, etc., in an outer casing.

[0117] The following describes each material and battery design.

[0118] [2-1. Non-aqueous electrolyte] The non-aqueous electrolyte includes the non-aqueous electrolyte described in [1. Non-aqueous electrolyte]. Furthermore, other non-aqueous electrolytes may be further included, to the extent that they do not significantly impair the effects of the present invention.

[0119] [2-2. Positive electrode] The positive electrode includes a positive electrode active material capable of intercalating and releasing metal ions, and the positive electrode active material may be in contact with at least a portion of the surface of the current collector.

[0120] [2-2-1. Positive electrode active material] The positive electrode active material is typically a lithium transition metal compound. Lithium transition metal compounds can include, for example, sulfides and phosphate compounds; silicates; borates; and lithium transition metal composite oxides. Among these, phosphate compounds and lithium transition metal composite oxides are preferred, and lithium transition metal composite oxides are more preferred. The lithium transition metal composite oxide may have, for example, a spinel structure that allows for three-dimensional diffusion; or a layered structure that enables two-dimensional diffusion of lithium ions.

[0121] The lithium transition metal composite oxide having the spinel structure is represented by the following compositional formula (1). Li x’ M'2O4···(1) (In equation (1), x' is 1 ≤ x' ≤ 1.5, and M' represents at least one transition metal element.) Examples of lithium transition metal composite oxides represented by the above compositional formula (1) include LiMn2O4, LiCoMnO4, and LiNi 0.5 Mn 1.5 It could be O4, LiCoVO4, etc.

[0122] The lithium transition metal composite oxide having the layered structure is represented by the following compositional formula (2). Li 1+x M y O2···(2) (In equation (2), x is -0.1 ≤ x ≤ 0.5, y is 0.5 ≤ y ≤ 1.48, and M represents at least one transition metal element.)

[0123] In equation (2), x is -0.1 ≤ x ≤ 0.5 and is not particularly limited, but it is preferably -0.1 ≤ x ≤ 0.1 and more preferably -0.05 ≤ x ≤ 0.05. In equation (2), y is 0.5 ≤ y ≤ 1.48 and is not particularly limited, but is preferably 0.9 ≤ y ≤ 1.1, more preferably 0.98 ≤ y ≤ 1.02, and even more preferably y = 1. In formula (2), M is not particularly limited as long as it is a transition metal element, but is preferably at least one element selected from the group consisting of Ni, Co, Mn, Al, Mg, Zr, Fe, Ti, and Er, more preferably at least one element selected from the group consisting of Ni, Co, Mn, and Al, and even more preferably at least one element selected from the group consisting of Ni, Co, and Mn.

[0124] The lithium transition metal composite oxide represented by the above compositional formula (2) is, for example, LiCoO2, LiNiO2, LiNi 0.85 Co 0.10 Al 0.05 O2, Lithium 0.80 Co 0.15 Al 0.05 O2, Lithium 0.33 Co 0.33 Mn 0.33 O2, Li 1.05 Ni 0.33 Co 0.33 Mn 0.33 O2, Li 1.00 Ni 0.61 Mn 0.19 Co 0.20 O2, Lithium 0.5 Co 0.2 Mn 0.3 O2, Li 1.05 Ni 0.5 Co 0.2 Mn 0.3 O2, Lithium 0.6 Co 0.2 Mn 0.2O2, Lithium 0.8 Co 0.1 Mn 0.1 It could be O2, etc. Among these, LiCoO2 is preferred as the positive electrode active material.

[0125] Furthermore, the lithium transition metal composite oxide is preferably a lithium transition metal composite oxide represented by the above compositional formula (2), and more preferably a transition metal composite oxide represented by the following compositional formula (3). Li a1 Ni b1 M c1 O2···(3) (In equation (3), a1, b1, and c1 are numerical values ​​satisfying 0.90 ≤ a1 ≤ 1.10, 0.30 ≤ b1 ≤ 0.98, and 0.01 ≤ c1 ≤ 0.5, respectively, and satisfying 0.50 ≤ b1 + c1 ≤ 1.48. M represents at least one element selected from the group consisting of Co, Mn, Al, Mg, Zr, Fe, Ti, and Er.)

[0126] In the above composition formula (3), a1 is 0.90 ≤ a1 ≤ 1.10 and is not particularly limited, but it is preferably 0.95 ≤ a1 ≤ 1.05. In the above compositional formula (3), b1 is 0.30 ≤ b1 ≤ 0.98 and is not particularly limited, but is preferably 0.50 ≤ b1 ≤ 0.98, and more preferably 0.60 ≤ b1 ≤ 0.98. In the above compositional formula (3), c1 is 0.01 ≤ c1 ≤ 0.5 and is not particularly limited, but is preferably 0.02 ≤ c1 ≤ 0.5, and more preferably 0.02 ≤ c1 ≤ 0.4. In formula (3), M is not particularly limited as long as it is at least one element selected from the group consisting of Co, Mn, Al, Mg, Zr, Fe, Ti, and Er, but it is more preferably at least one element selected from the group consisting of Co, Mn, and Al, and even more preferably at least one element selected from the group consisting of Co and Mn.

[0127] Furthermore, the transition metal composite oxide represented by the composition formula (3) is preferably the transition metal composite oxide represented by the composition formula (4) below. Li a2 Ni b2 Co c2 M d2 O2···(4) (In equation (4), a2, b2, c2, and d2 are numerical values ​​satisfying 0.90 ≤ a2 ≤ 1.10, 0.30 ≤ b2 ≤ 0.98, 0.01 ≤ c2 < 0.50, and 0.01 ≤ d2 < 0.50, respectively, and satisfying b2 + c2 + d2 = 1. M represents at least one element selected from the group consisting of Mn, Al, Mg, Zr, Fe, Ti, and Er.)

[0128] The lithium transition metal composite oxide represented by the above compositional formula (4) is, for example, LiNi 0.85 Co 0.10 Al 0.05 O2, Lithium 0.80 Co 0.15 Al 0.05 O2, Lithium 0.33 Co 0.33 Mn 0.33 O2, Lithium 0.5 Co 0.2 Mn 0.3 O2, Li 1.00 Ni 0.61 Mn 0.19 Co 0.20 O2, Li 1.05 Ni 0.50 Co 0.20 Mn 0.30 O2, Lithium 0.6 Co 0.2 Mn 0.2 O2, Lithium 0.8 Co 0.1 Mn 0.1 It could be O2, etc.

[0129] In the composition formula (4), a2 is 0.90 ≤ a2 ≤ 1.10 and is not particularly limited, but is preferably 0.95 ≤ a2 ≤ 1.05. In the composition formula (4), b2 is 0.30 ≤ b2 ≤ 0.98 and is not particularly limited, but is preferably 0.50 ≤ b2 ≤ 0.98 and more preferably 0.60 ≤ b2 ≤ 0.98. In the composition formula (4), c2 is 0.01 ≤ c2 < 0.50 and is not particularly limited, but is preferably 0.05 ≤ c2 ≤ 0.30. In the composition formula (4), d2 is 0.01 ≤ d2 < 0.50 and is not particularly limited, but is preferably 0.05 ≤ d2 ≤ 0.30. In the composition formula (4), M preferably contains Mn or Al, and more preferably contains Mn.

[0130] The lithium transition metal composite oxide may contain elements other than those included in the composition formula, but it is preferable that no other elements are introduced.

[0131] Furthermore, a positive electrode active material may be used in which a substance with a different composition from the positive electrode active material (hereinafter referred to as "surface-adhered substance") is attached to its surface. In this disclosure, the positive electrode active material with the surface-adhered substance attached is also referred to as the "positive electrode active material." The surface-adhered substance may be, for example, an oxide such as aluminum oxide; a sulfate such as lithium sulfate; a carbonate such as lithium carbonate; and so on. These can be attached to the surface of the positive electrode active material by, for example, dissolving or suspending the surface-adhering substance in a solvent and impregnating the positive electrode active material with it. The amount of surface-adhering material is typically 1 μmol / g to 1 mmol / g, and preferably 10 μmol / g to 1 mmol / g, relative to the total amount of positive electrode active material.

[0132] These positive electrode active materials may be used individually, or two or more may be used in any combination and ratio.

[0133] [2-2-2. Cathode Configuration and Manufacturing Method] The positive electrode can be manufactured by known methods such as, for example, a method of dry-mixing a positive electrode active material, a binder, and optionally a conductive material and a thickener, etc., forming a sheet, and pressing it onto a positive electrode current collector; or a method of dissolving or dispersing these materials in a solvent and applying a slurry to the current collector.

[0134] The positive electrode active material layer obtained by applying and drying the slurry is preferably compacted by hand pressing, roller pressing, or the like to increase the packing density. The density of the positive electrode active material layer on the current collector is typically 1.5 to 4.5 g / cm³. 3 The thickness of the positive electrode active material layer is typically 10 to 500 μm.

[0135] The following describes the materials used in the manufacture of the positive electrode.

[0136] The content of the positive electrode active material is typically 80-99.5% by mass of the total amount of the positive electrode.

[0137] The conductive material can be any known material, such as metallic materials like copper and nickel; or carbon-based materials like graphite, carbon black, carbon nanotubes, graphene, amorphous carbon, etc. The content of the conductive material is typically 0.01 to 50% by mass relative to the total amount of the positive electrode.

[0138] The binder can be a known material, such as fluororesins like polyvinyl fluoride, polyvinylidene fluoride, and polytetrafluoroethylene; or CN group-containing polymers like polyacrylonitrile and polyvinylidene cyanide. The content of the aforementioned binder is typically 0.1 to 80% by mass relative to the total amount of the positive electrode.

[0139] The current collector can be made of known materials, such as aluminum, stainless steel, nickel-plated metals, titanium, tantalum, etc. The shape of the current collector may be, for example, metal foil, metal cylinder, metal coil, metal plate, metal thin film, expanded metal, punched metal, foamed metal, etc. The thickness of the current collector is typically between 1 μm and 1 mm.

[0140] [2-3. Negative electrode] The negative electrode includes a negative electrode active material capable of intercalating and releasing metal ions, and the negative electrode active material may be in contact with at least a portion of the surface of the current collector.

[0141] [2-3-1. Negative electrode active material] The negative electrode active material is typically a carbon-based material, a material containing a metallic element and / or a metalloid element that can alloy with Li (hereinafter sometimes referred to as "a material containing a metallic element and / or a metalloid element that can alloy with Li"), a lithium-containing metal composite oxide, or a mixture thereof. Among these, it is preferable that the negative electrode active material be at least one selected from carbon-based materials, materials containing a metallic element and / or a metalloid element that can alloy with Li, and mixtures thereof.

[0142] Carbon-based materials typically include natural graphite, artificial graphite, amorphous carbon, carbon-coated graphite, graphite-coated graphite, and resin-coated graphite. The carbon-based material may be in particulate form, for example, after being treated with processes such as spheroidization or densification. In the case of particulate form, the average particle size (d50) is usually between 1 μm and 100 μm.

[0143] The carbon-based material preferably satisfies at least one of the following physical properties or shapes, etc., as shown in (1) to (4), and more preferably satisfies multiple properties simultaneously. Furthermore, the negative electrode active material preferably uses multiple types of carbon-based materials that satisfy the following characteristics or shapes, and more preferably contains two or more carbon-based materials that satisfy at least one physical property or shape selected from the group consisting of (i) different X-ray diffraction parameters, (ii) the distribution of volume-based average particle size is not symmetrical when centered on the median diameter, and (iii) different Raman R values.

[0144] (1) X-ray diffraction parameters The d-value (interlayer distance) of the lattice plane (002 plane) of the carbon-based material obtained by X-ray diffraction according to the Gakushin method is usually 0.335 nm to 0.360 nm. In addition, the crystallite size (Lc) of the carbonaceous material obtained by X-ray diffraction according to the Gakushin method is usually 1.0 nm or more.

[0145] (2) Volume-based average particle size The volume-based average particle size of the carbon-based material is a volume-based average particle size (median diameter) measured by laser diffraction or scattering method, and is usually 1 to 100 μm.

[0146] (3) Raman R value, Raman half-width at half-maximum The Raman R value of the carbon-based material is a value measured by argon ion laser Raman spectroscopy, and is usually 0.01 to 1.5. Furthermore, the 1580 cm -1 Raman half-width at half-maximum in the vicinity is usually 10 to 100 cm -1 -1

[0147] (4) BET specific surface area The BET specific surface area of the carbon-based material is a value measured by the BET method, and is usually 0.1 to 100 m 2 / g -1 .

[0148] For the material containing a metal element and / or metalloid element capable of alloying with Li, known materials can be used. From the viewpoint of capacity and cycle life, simple substances of metal elements and / or metalloid elements selected from the group consisting of Sb, Si, Sn, Al, As, and Zn; Li y ySi (0 < y ≦ 4.4), Li2SiO 2+z z (0 < z ≦ 2), and other alloys of Li with said metal elements and / or metalloid elements; oxides, nitrides or carbides of said metal elements and / or metalloid elements are preferred, metallic silicon (hereinafter referred to as Si) or Si-containing inorganic compounds are more preferred, and Si or SiO x x (0 < x ≦ 2) and other Si oxides are even more preferred.

[0149] When a material containing metallic and / or metalloid elements that can alloy with Li is in the form of particles, its average particle size (d50) is typically 0.01 to 10 μm in terms of cycle life.

[0150] A mixture of a carbon-based material and a material containing a metallic element and / or a metalloid element that can be alloyed with Li includes a mixture of the materials that are independent of each other, or a composite in which the materials are present on or inside each other. The content of particles of the material containing metal elements and / or metalloid elements that can alloy with Li, relative to the total amount of the mixture of the carbon-based material and the material containing metal elements and / or metalloid elements that can alloy with Li, is usually 1 to 99% by mass, preferably 1 to 50% by mass, and more preferably 1 to 25% by mass.

[0151] Lithium-containing metal composite oxides are more preferably lithium and titanium composite oxides (hereinafter referred to as "lithium-titanium composite oxides"), and lithium-titanium composite oxides having a spinel structure are more preferably. The lithium-titanium composite oxide is, for example, Li 4 / 3 Ti 5 / 3 O4, Li1Ti2O4, Li 4 / 5 Ti 11 / 5 It could be O4, etc.

[0152] Furthermore, the lithium and / or titanium in the lithium titanium composite oxide may be substituted with other metallic elements, for example, at least one element selected from the group consisting of Al, Ga, Cu, and Zn. The lithium titanium composite oxide in which part of the lithium and / or titanium is substituted with other elements is, for example, Li 4 / 3 Ti 4 / 3 Al 1 / 3 It could be O4.

[0153] Furthermore, at least one negative electrode active material selected from carbon-based materials, materials containing metal elements and / or metalloid elements that can be alloyed with Li, lithium-containing metal composite oxides, and mixtures thereof may have a substance of a different composition attached to its surface (surface-adhered substance). The surface-adhered substance may be, for example, an oxide such as aluminum oxide; a sulfate such as lithium sulfate; a carbonate such as lithium carbonate; and so on.

[0154] [2-3-2. Negative electrode configuration and manufacturing method] The negative electrode can be manufactured, for example, by known methods such as applying a slurry to a current collector, which is obtained by dissolving or dispersing a negative electrode active material, a binder, and optionally a thickener, binder, etc., in a solvent. The negative electrode active material layer obtained by applying and drying the slurry is preferably compacted by hand pressing, roller pressing, or the like to increase the packing density. The density of the negative electrode active material layer on the current collector is typically 1.0 to 2.2 g·cm³. -3 The thickness of the negative electrode active material layer is typically 15 to 300 μm.

[0155] The following describes the materials used in the manufacture of the negative electrode.

[0156] The content of the negative electrode active material in the negative electrode active material layer is typically 80-99.5% by mass.

[0157] The thickening agent can be any known material, such as carboxymethylcellulose, methylcellulose, hydroxymethylcellulose, ethylcellulose, or polyvinyl alcohol. The amount of the thickening agent is typically 0.1 to 5% by mass relative to the total amount of the negative electrode.

[0158] The binder can be made from known materials, such as rubbery polymers like SBR (styrene-butadiene rubber), isoprene rubber, butadiene rubber, fluororubber, NBR (acrylonitrile-butadiene rubber), and ethylene-propylene rubber; and fluorine-based polymers such as polyvinylidene fluoride, polytetrafluoroethylene, and tetrafluoroethylene-ethylene copolymer. The content of the binder, which mainly consists of rubbery polymers, is typically 0.1 to 5% by mass relative to the total amount of the negative electrode. The content of the binder, which mainly consists of rubbery polymers, is typically 1 to 15% by mass relative to the total amount of the negative electrode.

[0159] The current collector can be made of known materials, such as copper, aluminum, stainless steel, nickel-plated metals, titanium, tantalum, and other metallic materials. Furthermore, the shape of the current collector can be, for example, metal foil, metal cylinder, metal coil, metal plate, metal thin film, expanded metal, punched metal, foamed metal, etc. The thickness of the current collector is usually between 1 μm and 1 mm.

[0160] [2-4. Separator] A separator is usually placed between the positive and negative electrodes to prevent short circuits. In this case, the non-aqueous electrolyte is typically used by impregnating this separator. There are no particular restrictions on the material or shape of the separator; known materials can be used as long as they do not significantly impair the effects of the present invention.

[0161] [2-5.Battery design] Any electrode group can be used, such as an electrode group in which the positive electrode, the separator, and the negative electrode are stacked in that order, or an electrode group in which the stacked electrode group is wound in a spiral shape. The volume of the electrode group relative to the internal volume of the battery is usually 40-90% or less.

[0162] In the aforementioned laminated electrode group, a structure formed by bundling the metal core portions of each electrode layer and welding them to a terminal is preferably used. A structure that reduces resistance by providing multiple terminals within the electrode is also preferably used. In the aforementioned wound electrode group, the internal resistance can be reduced by providing multiple lead structures at the positive and negative electrodes and bundling them to a terminal.

[0163] Furthermore, protective elements such as PTC (Positive Temperature Coefficient) elements, which increase in resistance with heat generation due to excessive current, thermal fuses, thermistors, and valves (current interruption valves) that interrupt the current flowing through the circuit due to a rapid rise in internal pressure or temperature of the battery during abnormal heat generation can be used.

[0164] The outer casing can be made of known materials and is not particularly limited as long as it does not significantly impair the effects of the present invention. From the viewpoint of weight reduction, it is preferable to use aluminum or an aluminum alloy metal, or a laminate film for the outer casing. Furthermore, the shape of the outer casing can be cylindrical, rectangular, laminated, coin-shaped, large, etc. [Examples]

[0165] The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to these examples. The compounds used in the examples and comparative examples are as follows.

[0166] [ka]

[0167] A3 Triethylsilane (Et3SiH)

[0168] [ka]

[0169] <Example 1> [Preparation of non-aqueous electrolytes] Under a dry argon atmosphere, thoroughly dried LiPF6 was dissolved at a concentration of 1.0 mol / L in a mixed solvent consisting of ethylene carbonate and ethyl methyl carbonate (mixing volume ratio 30:70) as an electrolyte. Furthermore, monofluoroethylene carbonate, vinylene carbonate, lithium difluorophosphate, lithium fluorosulfonate, and lithium bisfluorosulfonylimide were added as auxiliary agents at 0.5% by mass each relative to the total volume of the electrolyte (the amount of each component being 0.5% by mass when the total volume of the non-aqueous electrolyte obtained in Example 1 is considered as 100% by mass), and this was used as the standard electrolyte. Furthermore, compound A1 was added at 1.0% by mass and compound B1 at 0.2% by mass (the amount such that the final amount of compound A1 is 1.0% by mass and the amount of compound B1 is 0.2% by mass when the total amount of the non-aqueous electrolyte according to Example 1 is considered to be 100% by mass), simultaneously with the auxiliary agent, to prepare the non-aqueous electrolyte according to Example 1.

[0170] [Fabrication of the positive electrode] 97 parts by mass of transition metal oxide (LiCoO2) as the positive electrode active material, 1.5 parts by mass of acetylene black as the conductive material, and 1.5 parts by mass of polyvinylidene fluoride as the binder were mixed in an N-methylpyrrolidone solvent using a disperser to form a slurry. This slurry was uniformly coated onto both sides of a 21 μm thick aluminum foil, dried, and then pressed to form the positive electrode.

[0171] [Fabrication of the negative electrode] Natural graphite powder was used as the negative electrode active material, an aqueous dispersion of sodium carboxymethylcellulose (1% by mass) as a thickener, and an aqueous dispersion of styrene-butadiene rubber (50% by mass) as a binder. These were mixed in a disperser to form a slurry. This slurry was uniformly applied to one side of a 12 μm thick copper foil, dried, and then pressed to form the negative electrode. The negative electrode was prepared with a mass ratio of natural graphite:sodium carboxymethylcellulose:styrene-butadiene rubber = 98:1:1 after drying.

[0172] [Manufacturing of non-aqueous electrolyte batteries (pouch type)] The positive electrode, negative electrode, and polypropylene separator described above were stacked in the order of negative electrode, separator, and positive electrode to create a battery element. The battery elements were inserted into a bag made of laminate film, which consists of aluminum (40 μm thick) coated on both sides with a resin layer, so that the positive and negative electrode terminals protruded from the bag. Then, the non-aqueous electrolyte obtained above was injected into the bag, and it was vacuum-sealed to produce a pouch-type battery, which was then made into a non-aqueous electrolyte battery.

[0173] <Examples 2-7, Comparative Examples 1-6> In Example 1, a non-aqueous electrolyte battery was prepared using the same reference electrolyte as in Example 1, except for the conditions shown in Table 1.

[0174] <Evaluation of non-aqueous electrolyte batteries> [Pre-test charge / discharge and discharge power capacity] Each non-aqueous electrolyte battery obtained in the examples and comparative examples was charged at 25°C for 4 hours with a constant current equivalent to 0.05C while sandwiched between glass plates to improve contact between electrodes, and then discharged to 3.0V with a constant current of 0.2C. Here, 1C represents the current value that discharges the battery's standard capacity in 1 hour, 0.5C represents half that current value, and 0.2C represents one-fifth that current value. Next, it was charged to 4.1V with a constant current equivalent to 0.1C, discharged to 3.0V with a constant current of 0.2C, then charged again with a constant current-constant voltage of 0.2C to 4.1V (0.05C cut), and then discharged to 3.0V with a constant current of 0.2C. After that, it was charged with a constant current-constant voltage of 0.2C to 4.2V (0.05C cut), and then discharged to 3.0V with a constant current of 0.2C. After that, it was charged with a constant current-constant voltage of 0.2C to 4.2V (0.05C cut), and then discharged to 3.0V with a constant current of 1.0C. The power capacity at 1.0C discharge was defined as the discharge power capacity. The results are shown in Table 1. Table 1 shows relative values ​​normalized to 100 for the discharge power capacity of Comparative Example 1. After that, it was charged at 0.2C with constant current and constant voltage up to 4.2V (0.05C cut-off).

[0175] [Failure suppression rate of battery current cutoff valve] The amount of gas generated during overcharging and during high-temperature continuous charging was measured using the method described below, and the difference between the two (the amount of gas generated during overcharging minus the amount of gas generated during high-temperature continuous charging) was defined as the malfunction suppression rate of the battery current cutoff valve. The higher the malfunction suppression rate of the battery current cutoff valve, the fewer false detections of gas generation due to causes other than overcharging, allowing for proper detection of gas generation during overcharging and proper operation of the battery current cutoff mechanism. Therefore, the battery can be judged to have superior reliability. The results are shown in Table 1. Note that Table 1 shows relative values ​​normalized to a 100 for the malfunction suppression rate of the battery current cutoff valve in Comparative Example 1.

[0176] (Measurement of gas amount generated during overcharging) Before the test, the volume of each non-aqueous electrolyte battery after charging and discharging was measured using Archimedes' principle. Then, with the batteries again sandwiched between glass plates, they were charged to 5.0V at 45°C with a constant current equivalent to 0.5C. After removing the glass plates, the volume of each non-aqueous electrolyte battery was measured again using Archimedes' principle. The change in volume before and after the test was defined as the amount of gas generated during overcharging.

[0177] (Measurement of gas generation during continuous high-temperature charging) Before the test, the volume of each non-aqueous electrolyte battery after charge and discharge was measured using Archimedes' principle. Then, with the batteries again sandwiched between glass plates, they were charged at 45°C at 0.2C to 4.25V with constant current and constant voltage (72-hour cut-off). After removing the glass plates, the volume of each non-aqueous electrolyte battery was measured again using Archimedes' principle. The volume change before and after the test was defined as the amount of gas generated during high-temperature continuous charging.

[0178] [Table 1]

[0179] Table 1 shows that the batteries of Examples 1 to 7, which contain electrolytes containing compounds A and B, have superior performance as batteries compared to the battery of Comparative Example 1, which contains electrolytes that do not contain compounds A and B, and the batteries of Comparative Examples 2, 3, and 4, which have electrolytes that do not contain either compound A or compound B. This is because they improve the discharge power capacity and the rate of suppression of malfunctions of the battery current cutoff valve.

Claims

1. A non-aqueous electrolyte containing an electrolyte, a non-aqueous solvent, a compound represented by the following general formula (1), and a compound represented by the following general formula (α), A non-aqueous electrolyte in which the ratio of the content of the compound represented by general formula (1) to the content of the compound represented by general formula (α) in the non-aqueous electrolyte is 0.1 or more and 1000 or less by mass. 【Chemistry 17】 In general formula (1), R ａ represents a hydrogen atom or an optionally substituted hydrocarbon group having 1 to 12 carbon atoms; R ｘ , R ｙ and R ｚ each independently represent a hydrogen atom, an optionally substituted hydrocarbon group having 1 to 12 carbon atoms, or a silyl group represented by -SiR １ R ２ R ３ ; R １ to R ３ each independently represent a hydrogen atom or an optionally halogen-substituted hydrocarbon group having 1 to 12 carbon atoms.) [Chemistry 18] (In general formula (α), R ８９ is a hydrogen atom or -SiR ８ R ９ R １０ This represents a silyl group represented by R ８ ~R １０ Each of these independently represents a hydrogen atom, a halogen atom, a C1-C12 hydrocarbon group which may have substituents, or a C1-C12 alkoxy group which may have substituents; R １１ is a hydrogen atom, a hydrocarbon group having 1 to 12 carbon atoms which may have substituents, or -SiR ｄ R ｅ R ｆ This represents a silyl group represented by R ｄ , R ｅ and R ｆ Each independently represents a hydrogen atom, a halogen atom, a C1-C12 hydrocarbon group which may have substituents, or a C1-C12 alkoxy group which may have substituents; Y represents a hydrogen atom, a halogen atom, a C1-C12 hydrocarbon group which may have substituents, a C1-C12 alkoxy group which may have substituents, -NR ｇ -SiR ｈ R ｉ R ｊ A group represented by -NR ｇ - Indicates a group represented by H; R ｇ R represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, which may have substituents; ｈ , R ｉ and R ｊ Each of these independently represents a hydrogen atom, a halogen atom, a C1-C12 hydrocarbon group which may have substituents, or a C1-C12 alkoxy group which may have substituents. １１ and R ｇ (They may be bonded to each other, forming a ring.)

2. The non-aqueous electrolyte according to claim 1, wherein the ratio of the content of the compound represented by general formula (1) to the content of the compound represented by general formula (α) in the non-aqueous electrolyte is 0.4 or more and 300 or less by mass.

3. The non-aqueous electrolyte according to claim 1 or 2, wherein the ratio of the content of the compound represented by general formula (1) to the content of the compound represented by general formula (α) in the non-aqueous electrolyte is 0.8 or more and 100 or less by mass.

4. The content of the compound represented by general formula (1) is 0.001 to 4% by mass relative to the total amount of the non-aqueous electrolyte. The non-aqueous electrolyte according to any one of claims 1 to 3, wherein the content of the compound represented by general formula (α) is 0.001 to 4% by mass relative to the total amount of the non-aqueous electrolyte.

5. R ｘ , R ｙ and R ｚ One or more of these are -SiR １ R ２ R ３ (R １ ~R ３ Each of these independently represents a silyl group represented by a hydrogen atom or a halogen atom, wherein each represents a hydrocarbon group having 1 to 12 carbon atoms. The non-aqueous electrolyte according to any one of claims 1 to 4.

6. R in general formula (1) ｘ , R ｙ and R ｚ One or more of these are -SiR １ｂ R ２ｂ R ３ｂ (R １ｂ ~R ３ｂ Each of these independently represents a C1-C12 alkyl group that may be substituted with a halogen atom, or a C1-C12 aryl group that may be substituted with a halogen atom.) A silyl group represented by any one of claims 1 to 5, a non-aqueous electrolyte according to any one of claims 1 to 5.

7. R in general formula (1) ｘ , R ｙ and R ｚ One or more of these are -SiR １ｃ R ２ｃ R ３ｃ (R １ｃ ~R ３ｃ Each of these independently represents a C1-C12 alkyl group which may be substituted with a halogen atom.) A non-aqueous electrolyte according to any one of claims 1 to 6, wherein the silyl group is represented by ().

8. R in equation (1) ａ A non-aqueous electrolyte according to any one of claims 1 to 7, wherein is a hydrogen atom.

9. R in equation (1) ａ The non-aqueous electrolyte according to any one of claims 1 to 7, wherein the hydrocarbon group having 1 to 12 carbon atoms may have substituents.

10. R in equation (1) ａ The non-aqueous electrolyte according to claim 9, wherein the aryl group having 1 to 12 carbon atoms may be substituted with a halogen atom.

11. In equation (α), Y is -NR ｇ -SiR ｈ R ｉ R ｊ A group represented by -NR ｇ A non-aqueous electrolyte according to any one of claims 1 to 10, wherein the group is represented by -H.

12. The non-aqueous electrolyte according to any one of claims 1 to 10, wherein Y in formula (α) is a hydrocarbon group having 1 to 12 carbon atoms, which may have substituents.

13. The non-aqueous electrolyte according to any one of claims 1 to 12, wherein the electrolyte contains lithium hexafluorophosphate, and the ratio of the content of hexafluorophosphate anion to the total content of the compound represented by general formula (α) and the compound represented by general formula (1) in the non-aqueous electrolyte is 50 to 30,000 by mass.

14. A non-aqueous electrolyte battery comprising a positive electrode, a negative electrode, and a non-aqueous electrolyte, A non-aqueous electrolyte battery, wherein the non-aqueous electrolyte is the non-aqueous electrolyte described in any one of claims 1 to 13.

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