JP5305446B2 - Nonaqueous electrolyte and nonaqueous electrolyte secondary battery using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a nonaqueous electrolyte for improving the cycle service life of the nonaqueous electrolyte secondary battery, suppressing the rise in resistance and improving the maintenance ratio for capacity; and to provide a nonaqueous electrolyte secondary battery. <P>SOLUTION: The nonaqueous electrolyte and the nonaqueous electrolyte secondary battery using the same are characterized by containing aprotic solvent and sulfonate indicated by general formulas (1): X<SB>1</SB>-R<SB>1</SB>-X<SB>2</SB>or (2): X<SB>3</SB>-R<SB>2</SB>-X<SB>4</SB>-R<SB>3</SB>-X<SB>5</SB>. X<SB>1</SB>to X<SB>5</SB>are each independently an disulfonic acid compound indicated by a general formula (3) in the general formulas (1), (2). A<SB>1</SB>and A<SB>2</SB>are each independently a 1-5C alkylene group substituted or not-substituted in the general formula (3). Connecting portions between R<SB>1</SB>to R<SB>3</SB>are A<SB>1</SB>or A<SB>2</SB>. Q<SB>1</SB>are each independently oxygen atom, methylene group or single bonds. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a non-aqueous electrolyte for a secondary battery and a non-aqueous electrolyte secondary battery using the same.

  Non-aqueous electrolyte lithium ion or lithium secondary batteries using carbon materials, oxides, lithium alloys or lithium metals for the negative electrode are attracting attention as power sources for mobile phones, laptop computers, etc. because they can achieve high energy density . In this secondary battery, it is known that a film called a surface film, a protective film, SEI (Solid Electrolyte Interface) or a film (hereinafter also referred to as “surface film”) is formed on the surface of the negative electrode. It has been. Since this surface film has a great influence on charge / discharge efficiency, cycle life and safety, it is known that control of the surface film is indispensable for improving the performance of the negative electrode. For carbon materials and oxide materials, it is necessary to reduce the irreversible capacity, and for lithium metal and alloy negative electrodes, it is necessary to solve the problem of safety due to the decrease in charge / discharge efficiency and the generation of dendrites (dendrites).

  Various techniques have been proposed as a technique for solving these problems. For example, it has been proposed to suppress the formation of dendrite by providing a film layer made of lithium fluoride or the like using a chemical reaction on the surface of lithium metal or lithium alloy.

Patent Document 1 discloses a technique in which a lithium negative electrode is exposed to an electrolytic solution containing hydrofluoric acid, and the negative electrode is reacted with hydrofluoric acid to cover the surface with a lithium fluoride film. Hydrofluoric acid is produced by the reaction of LiPF ₆ and a small amount of water. On the other hand, a surface film of lithium hydroxide or lithium oxide is formed on the surface of the lithium negative electrode by natural oxidation in air. When these react, a surface film of lithium fluoride is generated on the negative electrode surface. However, this lithium fluoride film is formed by utilizing the reaction between the electrode interface and the liquid, and side reaction components are easily mixed into the surface film, making it difficult to obtain a uniform film. In some cases, the surface film of lithium hydroxide or lithium oxide is not formed uniformly, or there is a part where lithium is exposed. In these cases, a uniform thin film cannot be formed, or a problem arises due to the reaction of water, hydrogen fluoride, or the like with lithium. In addition, when the reaction is insufficient, unnecessary compound components other than fluoride remain and may cause a decrease in ion conductivity. Furthermore, in the method of forming a fluoride layer using such a chemical reaction at the interface, the selection range of the available fluoride and electrolyte is limited, and it is difficult to form a stable surface film with a high yield. there were.

  In Patent Document 2, a mixed gas of argon and hydrogen fluoride and an aluminum-lithium alloy are reacted to obtain a lithium fluoride surface film on the negative electrode surface. However, when a surface film is present on the lithium metal surface in advance, particularly when a plurality of types of compounds are present, the reaction tends to be non-uniform, and it is difficult to form a lithium fluoride film uniformly. For this reason, it becomes difficult to obtain a lithium secondary battery having sufficient cycle characteristics.

  Patent Document 3 discloses a technique for forming a surface film structure mainly composed of a substance having a rock salt type crystal structure on the surface of a lithium sheet having a uniform crystal structure, that is, a (100) crystal plane preferentially oriented. It is disclosed. By carrying out like this, it is said that uniform precipitation dissolution reaction, ie, charge / discharge of a battery, can be performed, dendrite precipitation of lithium metal can be suppressed, and the cycle life of the battery can be improved. It is stated that the substance used for the surface film preferably has a halide of lithium, and it is preferable to use a solid solution of LiF with at least one selected from LiCl, LiBr, and LiI. Specifically, in order to form a solid solution film of at least one of LiCl, LiBr, and LiI and LiF, a lithium sheet with a (100) crystal plane preferentially oriented formed by pressing (rolling) is used. A negative electrode for a non-aqueous electrolyte battery is produced by immersing in an electrolyte containing at least one of chlorine molecules or chlorine ions, bromine molecules or bromine ions, iodine molecules or iodine ions and fluorine molecules or fluorine ions. . However, in Patent Document 3, a rolled lithium metal sheet is used, and since the lithium sheet is easily exposed to the atmosphere, a film derived from moisture or the like is easily formed on the surface, and the presence of active sites becomes nonuniform. Therefore, it was difficult to produce a stable surface film, and the effect of suppressing dendrite was not always sufficiently obtained.

Non-Patent Document 1 and Non-Patent Document 2 report the effect of a complex of a lanthanoid transition metal such as europium and an imide anion on a lithium metal negative electrode. Here, Eu (CF ₃ SO ₃ ) ₃ is further added to an electrolyte obtained by dissolving LiN (C ₂ F ₅ SO ₂ ) ₂ as a lithium salt in a mixed solvent of propylene carbonate or ethylene carbonate and 1,2-dimethoxyethane. A surface film made of Eu [(C ₂ F ₅ SO ₂ ) ₂ ] ₃ complex is formed on Li metal that is added as an additive and immersed in the electrolytic solution. This method is effective to some extent in improving the cycle life, but it is not sufficient. In addition, it is essential to use a relatively expensive lithium imide salt such as LiN (C ₂ F ₅ SO ₂ ) ₂ as the electrolyte. Other lithium salts (for example, generally LiPF ₆ ) or transition metals and CF Even if a complex composed of ₃ SO ³ -ion is added, a complex composed of a transition metal and an imide anion is not formed, so that the cycle characteristics are not improved. Furthermore, when lithium imide salt is used as an electrolyte, the resistance of the electrolyte solution is higher than when LiPF ₆ or the like is used, so that the internal resistance of the battery is increased.

  In addition, when a carbon material such as graphite or amorphous carbon capable of occluding and releasing lithium ions is used as the negative electrode, a technique for improving capacity and charge / discharge efficiency has been reported.

  In patent document 4, the negative electrode which coat | covered the carbon material with aluminum is proposed. Thereby, reductive decomposition on the carbon surface of solvent molecules solvated with lithium ions is suppressed, and deterioration of cycle life is suppressed. However, since aluminum reacts with a small amount of water, the capacity may decrease rapidly when the cycle is repeated.

  Patent Document 5 proposes a negative electrode in which the surface of a carbon material is covered with a thin film of a lithium ion conductive solid electrolyte. Thereby, it is said that the decomposition | disassembly of the solvent which arises when using a carbon material can be suppressed, and can provide the lithium ion secondary battery which can use especially a propylene carbonate. However, cracks generated in the solid electrolyte due to changes in stress during insertion and desorption of lithium ions lead to deterioration of characteristics. Further, due to non-uniformity such as crystal defects of the solid electrolyte, a uniform reaction cannot be obtained on the negative electrode surface, leading to deterioration of cycle life.

  In Patent Document 6, in a non-aqueous electrolyte secondary battery comprising a non-aqueous electrolyte containing a carbonic acid ester having a carbon material having a d-value of 3.37 mm or less on the lattice plane (002) plane as a negative electrode, vinylene carbonate is used. A secondary battery including a derivative is disclosed. Thereby, the decomposition of the non-aqueous electrolyte on the carbon negative electrode is suppressed, and the cycle characteristics of the non-aqueous secondary battery can be improved. However, there is still room for improvement in the performance of secondary batteries using vinylene carbonate and vinylene carbonate derivatives, and further improvements in high temperature characteristics and cycle characteristics are required.

  In Patent Document 7, the negative electrode is made of a material containing graphite, the cyclic electrolyte and the chain carbonate are the main components as the electrolytic solution, and 0.1 mass (hereinafter also referred to as wt)% or more and 4 wt% or less in the electrolytic solution. Secondary batteries containing 1,3-propane sultone and / or 1,4-butane sultone are disclosed. Here, 1,3-propane sultone or 1,4-butane sultone contributes to the formation of a passive film on the surface of the carbon material, and the active and highly crystallized carbon material such as natural graphite or artificial graphite is a passive film. It is considered that the coating has an effect of suppressing the decomposition of the electrolyte without impairing the normal reaction of the battery. However, this method has a problem that a sufficient film effect cannot be obtained, and charge due to decomposition of solvent molecules or anions appears as an irreversible capacity component, leading to a decrease in initial charge / discharge efficiency. In addition, the resistance of the generated film component is high, and there is a problem that the rate of increase in resistance with time is large especially at high temperatures. Patent Documents 8 and 9 disclose a method for producing a cyclic sulfonic acid ester having two sulfonyl groups. Moreover, the description as a compound which has a sulfonyl group is patent document 10 (sulfolane), patent documents 11-13 (1,3-propane sultone and 1,4-butane sultone), patent document 14 (alkanesulfonic acid anhydride), patent Document 15 (γ-sultone compound) and Patent Document 16 (sulfolene derivative). Moreover, it describes in patent documents 17-25 about vinylene carbonate or its derivative (s). Further, Patent Documents 26 to 27 describe cyclic compounds having a carbonyl group and a sulfonyl group.

JP-A-7-302617 JP-A-8-250108 Japanese Patent Laid-Open No. 11-288706 Japanese Patent Laid-Open No. 5-234583 JP-A-5-275077 JP-A-7-122296 JP 2000-3724 A Japanese Patent Publication No. 5-44946 U.S. Pat. No. 4,950,768 JP 60-154478 A JP-A-62-100948 JP 63-102173 A JP 11-339850 A JP-A-10-189041 JP 2000-235866 A JP 2000-294278 A JP-A-4-16975 JP-A-8-45545 JP-A-5-82138 Japanese Patent Laid-Open No. 5-74486 JP-A-6-52887 JP-A-11-260401 JP 2000-208169 A JP 2001-35530 A JP 2000-138071 A JP 2008-147117 A JP 2008-147118 A

2000 Electrochemical Fall Conference Abstracts 2A24 (2000) Abstracts of the 41st Battery Symposium 1E03 (2000)

  As described above, the conventional technology has not obtained a sufficient film effect for improving battery characteristics, and has the following problems.

  The surface film formed on the surface of the negative electrode is deeply related to charge / discharge efficiency, cycle life, and safety depending on its properties, but there is still no method for controlling the film for a long time. For example, when a surface film made of lithium halide or glassy oxide is formed on a layer made of lithium or an alloy thereof, a dendrite suppressing effect is obtained to a certain degree at the initial use, but when repeatedly used, The surface film is deteriorated and the function as a protective film is lowered. This is because a layer made of lithium or an alloy thereof changes in volume by occlusion / release of lithium, whereas a film made of lithium halide or the like located on the upper side hardly changes in volume. This is thought to be due to the generation of internal stress at the interface. By generating such internal stress, it is considered that a part of the surface film made of lithium halide or the like is particularly damaged, and the dendrite suppressing function is lowered.

  In addition, with respect to carbon materials such as graphite, a sufficient film effect cannot be obtained, and charge due to decomposition of solvent molecules or anions appears as an irreversible capacity component, leading to a decrease in initial charge / discharge efficiency. Further, the composition, crystal state, stability, etc. of the film produced at this time have a great influence on the subsequent efficiency and cycle life. Furthermore, the decomposition of the solvent of the electrolytic solution was promoted by a small amount of moisture present in the graphite or amorphous carbon negative electrode. When using graphite or an amorphous carbon negative electrode, it is also necessary to remove water molecules.

  As described above, the film formed on the surface of the negative electrode is deeply related to charge / discharge efficiency, cycle life, safety, etc. depending on its properties, but there is still no method for controlling the film for a long period of time. It has been desired to develop an electrolytic solution that forms a film that leads to stable and sufficient charge / discharge efficiency.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to suppress the decomposition of the solvent, improve the cycle life of the secondary battery, suppress the increase in resistance of the secondary battery, and An object of the present invention is to provide a non-aqueous electrolyte that improves the capacity retention rate of the battery and a non-aqueous electrolyte secondary battery using the same.

  The present inventors have found that the above problems can be solved by adding a multimerized cyclic disulfonic acid ester compound in an electrolytic solution using an aprotic solvent as a solvent, and have reached the present invention.

According to the present invention, there can be obtained a nonaqueous electrolytic solution comprising an aprotic solvent, a supporting salt, and any of the disulfonic acid ester compounds represented by the following general formula (1) or (2). .
X ₁ -R ₁ -X ₂ (1)
_{X 3 -R 2 -X 4 -R 3} -X 5 (2)
However, in the general formulas (1) and (2), X _{1 to} X ₅ are each independently a disulfonic acid ester compound represented by the following general formula (3), and R _{1 to} R ₃ are each independently A bond or a substituted or unsubstituted alkylene group having 1 to 5 carbon atoms.

However, in the general formula (3), A ₁ and A ₂ are each independently a substituted or unsubstituted alkylene group having 1 to 5 carbon atoms. The binding site for R _{1 to} R ₃ is A ₁ or A ₂ . Q ₁ is independently an oxygen atom, a methylene group or a single bond.

  In addition to the compound represented by the general formula (1), the present invention preferably includes one or more compounds having a sulfonyl group. The one or more compounds having a sulfonyl group are represented by the following general formula (4). It is preferable to contain the compound.

However, the general formula (4), Q ₂ represents an oxygen atom, a methylene group or a single bond, A ₃ is a substituted or unsubstituted alkylene group having 1 to 5 carbon atoms, a carbonyl group, a sulfinyl group, 1 carbon atoms 5 polyfluoroalkylene group, a substituted or unsubstituted fluoroalkylene group having 1 to 5 carbon atoms, or a substituted or unsubstituted alkylene group having 1 to 5 carbon atoms at least one position of C—C bond is C—O—C. A group having a bond, a group in which at least one C—C bond in the C 1-5 polyfluoroalkylene group is a C—O—C bond, and a substituted or unsubstituted C 1-5 fluoro A group selected from a group in which at least one C—C bond in the alkylene group is a C—O—C bond. A ₄ represents a group selected from a substituted or unsubstituted alkylene group having 1 to 5 carbon atoms, a polyfluoroalkylene group having 1 to 6 carbon atoms, and a substituted or unsubstituted fluoroalkylene group having 1 to 5 carbon atoms. .

  Furthermore, the present invention preferably includes a sultone compound represented by the following general formula (5) as one or more compounds having the sulfonyl group.

However, in the said General formula (5), n is an integer of 0-2. R _{4 to} R ₉ represent a group selected from a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, and an aryl group having 6 to 12 carbon atoms.

Furthermore, in the present invention, the compound represented by the general formula (1) or (2) is preferably contained in an amount of 0.005% by mass or more and 10% by mass or less of the entire electrolytic solution, and includes vinylene carbonate or a derivative thereof. Preferably, the aprotic solvent is a group consisting of cyclic carbonates, chain carbonates, aliphatic carboxylic acid esters, γ-lactones, cyclic ethers, chain ethers, and fluorine derivatives thereof. preferably includes one or more solvents selected from, as the supporting _{salt, LiPF 6, LiBF 4, LiAsF} 6, LiSbF 6, LiClO 4, LiAlCl 4, and _{LiN (C p F 2p + 1} SO 2 ) (C _q F _{2q + 1} SO ₂ ) (p and q are natural numbers), preferably one or more substances selected from the group consisting of.

  In addition, according to the present invention, a non-aqueous electrolyte secondary battery comprising the non-aqueous electrolyte, at least a positive electrode, and a negative electrode is obtained. A lithium-containing composite oxide is used as a positive electrode active material of the positive electrode. Preferably, the negative electrode active material of the negative electrode is selected from the group consisting of a material that can occlude and release lithium, a lithium metal, a metal material that can form an alloy with lithium, and an oxide material. Two or more substances are preferably included, and the negative electrode active material preferably includes a carbon material such as graphite or amorphous carbon.

  The electrolytic solution for a secondary battery according to the present invention contains a disulfonic acid ester represented by the general formula (1) or (2), and the compound represented by the general formula (1) or (2) is present at the electrode interface of the battery. It contributes to the formation of passive film and consequently suppresses the decomposition of solvent molecules. Further, when the positive electrode is an oxide containing manganese, elution of manganese is suppressed, and the eluted manganese is prevented from adhering to the negative electrode. Therefore, by using the secondary battery electrolyte solution according to the present invention for a non-aqueous electrolyte secondary battery, a non-aqueous electrolyte solution can be formed from the effects such as forming a film on the negative electrode and reducing the influence on elution of manganese and the like. The cycle characteristics of the secondary battery can be improved, and an increase in resistance can be suppressed.

  According to the present invention, by using an electrolytic solution containing an aprotic organic solvent, a supporting salt, and a compound represented by the above general formula (1) or (2), electrolysis of a non-aqueous electrolyte secondary battery is performed. The decomposition of the solvent of the liquid can be suppressed. Further, according to the present invention, the charge / discharge efficiency and cycle life of the nonaqueous electrolyte secondary battery can be improved. In addition, according to the present invention, it is possible to suppress an increase in resistance of the nonaqueous electrolyte secondary battery. In addition, according to the present invention, the capacity retention rate of the nonaqueous electrolyte secondary battery can be improved. In addition, the electrolyte solution for secondary batteries according to the present invention is simple and stable by a step of dissolving the compound represented by the general formula (1) or (2) and a step of dissolving a lithium salt in a solvent. Manufactured.

The schematic block diagram of the nonaqueous electrolyte secondary battery of this invention.

Hereinafter, the configuration of the non-aqueous electrolyte of the present invention will be described. The nonaqueous electrolytic solution contains an aprotic solvent, a supporting salt, and a disulfonic acid ester represented by the following general formula (1) or (2).
X ₁ -R ₁ -X ₂ (1)
_{X 3 -R 2 -X 4 -R 3} -X 5 (2)
However, in the general formulas (1) and (2), X _{1 to} X ₅ are each independently a disulfonic acid ester compound represented by the following general formula (3), and R _{1 to} R ₃ are each independently A bond or a substituted or unsubstituted alkylene group having 1 to 5 carbon atoms.

However, in the general formula (3), A ₁ and A ₂ are each independently a substituted or unsubstituted alkylene group having 1 to 5 carbon atoms. The binding site for R _{1 to} R ₃ is A ₁ or A ₂ . Q ₁ is independently an oxygen atom, a methylene group or a single bond.

  In the general formula (1) or (2), the substituted or unsubstituted alkylene group having 1 to 5 carbon atoms may be a methylene group, an ethylene group, an n-propylene group, or an n-butylene group. , 2-methylpropylene group, 1-chloroethylene group, 1-fluoro-3-chlorobutylene group and the like are typical examples, and a methylene group or an ethylene group is more preferable. Thereby, the raise of the viscosity of a non-aqueous electrolyte and the accompanying increase in resistance can be suppressed.

  In the present invention, the effect of increasing the amount of the disulfonic acid ester compound is not clear, but a more stable film is formed on the electrode surface by causing a polymerization reaction due to an electrochemical reaction at the time of charge and discharge of the battery. It is conceivable to suppress degradation of battery characteristics in cycle characteristics and storage characteristics by suppressing the decomposition reaction of the liquid and the supporting salt.

  Hereinafter, typical examples of the compounds represented by the general formulas (1) and (2) are specifically exemplified in Table 1, but the present invention is not limited thereto.

The compound represented by the general formula (1) or (2) can be obtained, for example, using the production method described in Patent Document 8 or Patent Document 9. For example, Compound No. 2 in Table 1 (hereinafter referred to as Compound No. 2) is obtained by reacting (SO ₂ Cl) ₂ CHCH ₂ CH (SO ₂ Cl) ₂ with silver carbonate and then reacting with X-CH ₂ -X (X Can be synthesized by reacting with = Cl or I).

  The proportion of the compound represented by the general formula (1) or (2) in the nonaqueous electrolytic solution is not particularly limited, but is included in 0.005 to 10 mass (hereinafter referred to as wt)% of the entire nonaqueous electrolytic solution. Is preferred. By setting the concentration of the compound represented by the general formula (1) or (2) to 0.005 wt% or more, a sufficient film effect can be obtained. More preferably, 0.01 wt% or more is added. By doing so, the battery characteristics can be further improved. Moreover, by setting it as 10 wt% or less, the raise of the viscosity of a nonaqueous electrolyte and the accompanying increase in resistance can be suppressed. More preferably, 5 wt% or less is added, and by doing so, the battery characteristics can be further improved.

  In addition to the compound represented by the general formula (1) or (2), the nonaqueous electrolytic solution may further include one or more compounds having a sulfonyl group. For example, you may include the compound shown by following General formula (4).

However, the above general formula (4), Q ₂ represents an oxygen atom, a methylene group or a single bond, A ₃ is a substituted or unsubstituted alkylene group having 1 to 5 carbon atoms, a carbonyl group, a sulfinyl group, 1 carbon atoms 5 polyfluoroalkylene group, a substituted or unsubstituted fluoroalkylene group having 1 to 5 carbon atoms, or a substituted or unsubstituted alkylene group having 1 to 5 carbon atoms at least one position of C—C bond is C—O—C. A group having a bond, a group in which at least one C—C bond in the C 1-5 polyfluoroalkylene group is a C—O—C bond, and a substituted or unsubstituted C 1-5 fluoro A group selected from a group in which at least one C—C bond in the alkylene group is a C—O—C bond. A ₄ represents a group selected from a substituted or unsubstituted alkylene group having 1 to 5 carbon atoms, a polyfluoroalkylene group having 1 to 6 carbon atoms, and a substituted or unsubstituted fluoroalkylene group having 1 to 5 carbon atoms. .

  The nonaqueous electrolytic solution contains a compound represented by the general formula (4). The compound represented by the general formula (4) further suppresses the decomposition of the solvent molecules. Moreover, when the positive electrode is an oxide containing manganese, the influence on elution of manganese and the like can be more reliably mitigated. For this reason, the cycle characteristics of the nonaqueous electrolyte secondary battery can be further improved. In addition, an increase in resistance of the nonaqueous electrolyte secondary battery can be suppressed.

In the general formula (4), the number of carbon atoms of A ₃ indicates the number of carbon atoms constituting the ring, and does not include the number of carbon atoms contained in the side chain. When A ₃ is a substituted or unsubstituted fluoroalkylene group having 2 to 5 carbon atoms, A ₃ may have a methylene unit and a fluoromethylene unit, or may have only a fluoromethylene unit. Good. Moreover, when the alkylene unit or the fluoroalkylene unit is bonded via an ether bond, the alkylene units may be bonded, the fluoroalkylene units may be bonded, or the alkylene unit and A fluoroalkylene unit may be bonded.

  Examples of the compound represented by the general formula (4) include compounds shown in JP-A No. 2004-281368 such as ethylene methane disulfonate and methylene methane disulfonate.

  Moreover, as a compound which has a sulfonyl group, the sultone compound shown, for example by following General formula (5) can be included.

However, in the said General formula (5), n is an integer of 0-2. R _{4 to} R ₉ represent a group selected from a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, and an aryl group having 6 to 12 carbon atoms. )

  In addition to the compound represented by the general formula (1) or (2), the viscosity of the nonaqueous electrolytic solution can be easily adjusted by adding the compound having a sulfonyl group represented by the general formula (4) or (5). Moreover, the stability of the film is improved by a synergistic effect by using a compound having a sulfonyl group in combination. Moreover, the decomposition suppression of the solvent molecule can be suppressed. Further, the effect of removing moisture in the non-aqueous electrolyte is increased.

  Specific examples of the compound having a sulfonyl group include sulfolane (see Patent Document 10), 1,3-propane sultone and 1,4-butane sultone (see Patent Documents 7, 11, 12, and 13), and alkanesulfonic anhydride. Products (see Patent Document 14), γ-sultone compounds (see Patent Document 15), sulfolene derivatives (see Patent Document 16), and the like, but are not limited thereto.

  In addition to the general formula (1) or (2), when a sulfonyl compound is further added to the non-aqueous electrolyte, the amount of the sulfonyl compound added is, for example, 0.005 wt% or more and 10 wt% or less in the non-aqueous electrolyte. Can be added. By setting the content to 0.005 wt% or more, a film can be effectively formed on the negative electrode surface. More preferably, it can be 0.01 wt% or more. Moreover, the solubility of a sulfonyl compound is maintained by setting it as 10 wt% or less, and the viscosity rise of a non-aqueous electrolyte can be suppressed. More preferably, it can be 5 wt% or less.

  A non-aqueous electrolyte solution is obtained by dissolving or dispersing a compound represented by the general formula (1) or (2) in an aprotic solvent, and a compound having a sulfonyl group, a lithium salt, or other additives as necessary. can get. By mixing additives having different properties, a film having different properties is formed on the negative electrode surface, which is effective in improving battery characteristics.

  Further, by adding vinylene carbonate (VC) or a derivative thereof to the non-aqueous electrolyte, it is possible to improve the cycle characteristics and the resistance increase suppressing effect of the non-aqueous electrolyte secondary battery. As vinylene carbonate or a derivative thereof, for example, compounds shown in Patent Document 6 and Patent Documents 17 to 25 can be used as appropriate.

  The addition amount of VC or a derivative thereof is preferably 0.01 wt% or more and 10 wt% or less of the whole non-aqueous electrolyte. By setting it to 0.01 wt% or more, the cycle characteristics can be suitably exhibited, and further, it is possible to suppress an increase in resistance during storage at a high temperature. By setting it to 10 wt% or less, the resistance value of the non-aqueous electrolyte can be lowered.

The nonaqueous electrolytic solution may further include a lithium salt as an electrolyte. In this way, since lithium ions can be used as a mobile substance, battery characteristics can be improved. Examples of lithium salts include lithium imide salts, LiPF ₆ , LiBF ₄ , LiAsF ₆ , LiSbF ₆ , LiClO ₄ , LiAlCl ₄ , LiN (C _p F _{2p + 1} SO ₂ ) (C _q F _{qm + 1} SO ₂ ) (p, q may include one or more substances selected from natural numbers). In particular, LiPF ₆ or LiBF ₄ is preferably used. By using these, the electrical conductivity of the lithium salt can be increased, and the cycle characteristics of the nonaqueous electrolyte secondary battery can be further improved.

  The non-aqueous electrolyte includes, as an aprotic solvent, cyclic carbonates, chain carbonates, aliphatic carboxylic acid esters, γ-lactones, cyclic ethers, chain ethers, and fluorine derivatives of any of these, One or more solvents selected from the group consisting of can be included.

  Specifically, for example, cyclic carbonates such as propylene carbonate (PC), ethylene carbonate (EC), butylene carbonate (BC), vinylene carbonate (VC), dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), chain carbonates such as dipropyl carbonate (DPC), aliphatic carboxylic acid esters such as methyl formate, methyl acetate and ethyl propionate, γ-lactones such as γ-butyrolactone, 1,2-ethoxy Chain ethers such as ethane (DEE) and ethoxymethoxyethane (EME), cyclic ethers such as tetrahydrofuran and 2-methyltetrahydrofuran, dimethyl sulfoxide, 1,3-dioxolane, formamide, acetamide, dimethylphenol Rumamide, acetonitrile, propylnitrile, nitromethane, ethyl monoglyme, phosphoric acid triester, trimethoxymethane, dioxolane derivative, sulfolane, methylsulfolane, 1,3-dimethyl-2-imidazolidinone, 3-methyl-2-oxazolidinone, Propylene carbonate derivative, tetrahydrofuran derivative, ethyl ether, N-methylpyrrolidone, fluorinated carboxylic acid ester, methyl-2,2,2-trifluoroethyl carbonate, methyl-2,2,3,3,3-pentafluoropropyl carbonate , Trifluoromethyl ethylene carbonate, monofluoromethyl ethylene carbonate, difluoromethyl ethylene carbonate, 4,5-difluoro-1,3-dioxolan-2-one, monofluoroe Of such alkylene carbonate, it can be used by mixing one or two or more.

  Hereinafter, the configuration of the nonaqueous electrolyte secondary battery of the present invention will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram of a non-aqueous electrolyte secondary battery of the present invention.

  The nonaqueous electrolyte secondary battery according to the present invention has a structure as shown in FIG. The positive electrode is formed by forming a layer 12 containing a positive electrode active material on the positive electrode current collector 11. The negative electrode is formed by forming a layer 13 containing a negative electrode active material on a negative electrode current collector 14. The positive electrode and the negative electrode are disposed to face each other with a non-aqueous electrolyte and a porous separator 16 in the non-aqueous electrolyte. The porous separator 16 is disposed substantially parallel to the layer 13 containing the negative electrode active material.

  In the non-aqueous electrolyte secondary battery of FIG. 1, the negative electrode active material used for the layer 13 containing the negative electrode active material is selected from the group consisting of, for example, lithium metal, lithium alloy, and a material capable of inserting and extracting lithium. One or more substances can be used. As a material that absorbs and releases lithium ions, a carbon material or an oxide can be used.

  As the carbon material, graphite that occludes lithium, amorphous carbon, diamond-like carbon, carbon nanotube, or a composite oxide thereof can be used. Among these, graphite material or amorphous carbon is particularly preferable. In particular, the graphite material has high electron conductivity, excellent adhesion to a current collector made of a metal such as copper, and voltage flatness, and is formed at a high processing temperature, so it contains few impurities and has negative electrode performance. It is advantageous for improvement and is preferable.

  Further, as the oxide, any of silicon oxide, tin oxide, indium oxide, zinc oxide, lithium oxide, phosphoric acid, boric acid, or a composite thereof may be used, and it is particularly preferable to include silicon oxide. . The structure is preferably in an amorphous state. This is because silicon oxide is stable and does not cause a reaction with other compounds, and the amorphous structure does not lead to deterioration due to non-uniformity such as crystal grain boundaries and defects. As a film forming method, a vapor deposition method, a CVD method, a sputtering method, or the like can be used.

  The lithium alloy is composed of lithium and a metal capable of forming an alloy with lithium. For example, it is composed of a binary or ternary alloy of metal such as Al, Si, Pb, Sn, In, Bi, Ag, Ba, Ca, Hg, Pd, Pt, Te, Zn, La and lithium. The As the lithium metal or lithium alloy, an amorphous one is particularly preferable. This is because the amorphous structure hardly causes deterioration due to non-uniformity such as crystal grain boundaries and defects.

  Lithium metal or lithium alloy is formed by an appropriate method such as a melt cooling method, a liquid quenching method, an atomizing method, a vacuum deposition method, a sputtering method, a plasma CVD method, a photo CVD method, a thermal CVD method, a sol-gel method, etc. Can do.

  In the negative electrode of the non-aqueous electrolyte secondary battery in FIG. 1, when a complex composed of a transition metal cation and an imide anion is present at the interface with the non-aqueous electrolyte, the negative electrode is flexible with respect to the volume change of the metal and alloy phases. This is preferable because it is excellent in uniformity of ion distribution and physical / chemical stability. As a result, dendrite formation and lithium atomization can be effectively prevented, and cycle efficiency and life are improved.

  In addition, when a carbon material or an oxide material is used as the negative electrode, dangling bonds present on the surface have high chemical activity and easily decompose the solvent. By adsorbing a complex composed of a transition metal cation and an imide anion on this surface, the decomposition of the solvent is suppressed and the irreversible capacity is greatly reduced, so that the charge / discharge efficiency can be kept high.

  Furthermore, when the film is mechanically broken, lithium fluoride, which is a reactive product of lithium on the negative electrode surface and the imide anion adsorbed on the negative electrode surface, has a function of repairing the film. Even after the film is destroyed, it has the effect of leading to the formation of a stable surface compound.

In the non-aqueous electrolyte secondary battery of FIG. 1, examples of the positive electrode active material used for the layer 12 containing the positive electrode active material include lithium-containing composite oxides such as LiCoO ₂ , LiNiO ₂ , and LiMn ₂ O _4. . Further, the transition metal portion of these lithium-containing composite oxides may be replaced with other elements.

Alternatively, a lithium-containing composite oxide having a plateau at 4.5 V or more at the metal lithium counter electrode potential can be used. Examples of the lithium-containing composite oxide include spinel-type lithium manganese composite oxide, olivine-type lithium-containing composite oxide, and reverse spinel-type lithium-containing composite oxide. The lithium-containing composite oxide can be, for example, a compound represented by the following general formula (6).
Li _a (M _x Mn _2-x ) O ₄ (6)
However, in the above general formula (6), 0 <x <2 and 0 <a <1.2. M is at least one selected from the group consisting of Ni, Co, Fe, Cr and Cu.

  The positive electrode is obtained by dispersing and kneading these active materials in a solvent such as N-methyl-2-pyrrolidone (NMP) together with a conductive material such as carbon black and a binder such as polyvinylidene fluoride (PVDF). Can be obtained by coating on a substrate such as an aluminum foil.

  The non-aqueous electrolyte secondary battery of FIG. 1 has a negative electrode and a positive electrode laminated via a porous separator 16 in a dry air or inert gas atmosphere. It accommodates in exterior bodies, such as a flexible film which consists of a laminated body of resin and metal foil, and is impregnated with the nonaqueous electrolyte solution containing the compound shown by the said General formula (1) or (2). And a film | membrane can be formed on a negative electrode by charging a nonaqueous electrolyte secondary battery after sealing or sealing an exterior body. In addition, as the porous separator 16, porous films, such as polyolefin, such as a polypropylene and polyethylene, a fluororesin, are used.

  The shape of the nonaqueous electrolyte secondary battery according to the present embodiment is not particularly limited, and examples thereof include a cylindrical shape, a square shape, a laminate outer shape, and a coin shape.

Example 1
(Production of battery)
The production of the battery of this example will be described. An aluminum foil having a thickness of 20 μm was used as the positive electrode current collector, and LiMn ₂ O ₄ was used as the positive electrode active material. Further, a copper foil having a thickness of 10 μm was used as the negative electrode current collector, and a negative electrode active material obtained by vapor deposition of 20 μm thick lithium metal as the negative electrode active material was used as the negative electrode. Further, a mixed solvent of EC and DEC (volume ratio: 30/70) is used as the solvent of the electrolytic solution, and LiN (C ₂ F ₅ SO ₂ ) ₂ (hereinafter abbreviated as LiBETI) is used as 1 mol L ⁻ as the supporting electrolyte. ^{1 was} further dissolved, and further, Compound No. 1 (hereinafter referred to as “No.”) 1 described in Table 1 was added so that 1% by mass was contained in the electrolytic solution. And the negative electrode and the positive electrode were laminated | stacked through the separator which consists of polyethylene, and the nonaqueous electrolyte secondary battery of a present Example was produced.

(Charge / discharge cycle test)
At a temperature of 20 ° C., the charge rate was 0.05 C, the discharge rate was 0.1 C, the charge end voltage was 4.2 V, the discharge end voltage was 3.0 V, and the utilization factor (discharge depth) of the lithium metal negative electrode was 33%. The impedance at the initial stage and after 400 cycles was measured using a frequency response analyzer and a potentio / galvanostat to calculate the charge transfer resistance. The resistance increase rate is a value obtained by dividing the charge transfer resistance after 400 cycles by the initial charge transfer resistance. The obtained results are shown in Table 2. The capacity retention rate (%) is a value obtained by dividing the discharge capacity (mAh) after 400 cycles by the discharge capacity (mAh) at the 10th cycle. Table 3 shows the results obtained in the cycle test.

(Examples 2-3)
In Example 1, compound no. A nonaqueous electrolyte secondary battery was produced in the same manner as in Example 1 except that the concentration of 1 was changed to the concentration shown in Table 2. Then, the resistance increase rate was calculated in the same manner as in Example 1. The obtained results are shown in Table 2.

(Reference Examples 1-2)
In Example 1, compound no. A nonaqueous electrolyte secondary battery was produced in the same manner as in Example 1 except that the concentration of 1 was changed to the concentration shown in Table 2. The charge transfer resistance was calculated in the same manner as in Example 1. The results are shown in Table 2.

  From Table 2, it was confirmed that the batteries shown in Examples 1 to 3 have a reduced resistance increase rate as compared with Reference Examples 1 and 2.

(Examples 4 to 6)
In Example 1, compound no. A nonaqueous electrolyte secondary battery was produced in the same manner as in Example 1 except that the compounds shown in Table 2 were used instead of 1. Then, the capacity retention rate (%) was examined in the same manner as in Example 1. The results are shown in Table 3.

(Comparative Example 1)
In Example 1, compound no. A nonaqueous electrolyte secondary battery was produced in the same manner as in Example 1 except that 1 was not added. Then, the capacity retention rate (%) was examined in the same manner as in Example 1. The results are shown in Table 3.

(Comparative Example 2)
In Example 1, compound no. A nonaqueous electrolyte secondary battery was fabricated in the same manner as in Example 1 except that 1,3-propane sultone (hereinafter also referred to as 1,3-PS) was used instead of 1. Then, the capacity retention rate (%) was examined in the same manner as in Example 1. The results are shown in Table 3.

  From Table 3, the batteries shown in Examples 1 and 4 to 6 have an improved capacity retention rate after the cycle test, that is, improved cycle characteristics, as compared with Comparative Examples 1 and 2. Was confirmed.

(Example 7)
In Example 1, LiPF ₆ was used instead of LiBETI as the supporting electrolyte, and the negative electrode was mixed with polyvinylidene fluoride dissolved in N-methyl-2-pyrrolidone as a binder and a conductive material as a negative electrode, and paste-like. A non-aqueous electrolyte secondary battery was produced in the same manner as in Example 1 except that the dried product was applied to a copper foil and dried.

  In the charge / discharge cycle test, at a temperature of 20 ° C., both the charge rate and the discharge rate were 1 C, the charge end voltage was 4.2 V, and the discharge end voltage was 3.0 V. The capacity retention rate (%) is a value obtained by dividing the discharge capacity (mAh) after 400 cycles by the discharge capacity (mAh) at the 10th cycle. Table 4 shows the results obtained in the cycle test.

(Examples 8 to 9)
In Example 7, compound no. A nonaqueous electrolyte secondary battery was produced in the same manner as in Example 7 except that the compounds shown in Table 4 were used instead of 1. And the characteristic of the battery was investigated similarly to Example 7. The results are shown in Table 4.

(Comparative Example 3)
In Example 7, compound no. A nonaqueous electrolyte secondary battery was produced in the same manner as in Example 7 except that 1 was not added. And the characteristic of the battery was investigated similarly to Example 7. The results are shown in Table 4.

  From Table 4, it was confirmed that the batteries shown in Examples 7 to 9 had an improved capacity retention rate after the cycle test, that is, improved cycle characteristics, as compared with Comparative Example 3. .

(Example 10)
In Example 7, non-crystalline carbon was used instead of graphite, and the main solvent of the electrolytic solution was PC / EC / DEC (volume ratio: 20/20/60). A water electrolyte secondary battery was produced. And the characteristic of the battery was investigated similarly to Example 7. The results are shown in Table 5.

(Examples 11 to 12)
In Example 10, compound no. A nonaqueous electrolyte secondary battery was produced in the same manner as in Example 10 except that the compounds shown in Table 5 were used instead of 1. And the characteristic of the battery was investigated similarly to Example 10. The results are shown in Table 5.

(Comparative Example 4)
In Example 10, compound no. A nonaqueous electrolyte secondary battery was produced in the same manner as in Example 10 except that 1 was not added. And the characteristic of the battery was investigated similarly to Example 10. The results are shown in Table 5.

  From Table 5, it was confirmed that the batteries shown in Examples 10 to 12 had an improved capacity retention rate after the cycle test, that is, improved cycle characteristics, as compared with Comparative Example 4. .

(Example 13)
In Example 4, a nonaqueous electrolyte secondary battery was produced in the same manner as in Example 4 except that the electrolyte solution further contained 1 wt% of ethylenemethane disulfonate. And the characteristic of the battery was investigated similarly to Example 4. The results are shown in Table 6.

(Example 14)
In Example 13, compound no. A nonaqueous electrolyte secondary battery was produced in the same manner as in Example 13 except that the compounds shown in Table 6 were used instead of 2. The battery characteristics were examined in the same manner as in Example 13. The results are shown in Table 6.

(Example 15)
In Example 13, a non-aqueous electrolyte secondary battery was produced in the same manner as in Example 13 except that methylene methane disulfonate was used instead of ethylene methane disulfonate. The battery characteristics were examined in the same manner as in Example 13. The results are shown in Table 6.

(Example 16)
In Example 15, compound no. A nonaqueous electrolyte secondary battery was produced in the same manner as in Example 15 except that the compounds shown in Table 6 were used instead of 2. And the characteristic of the battery was investigated similarly to Example 15. The results are shown in Table 6.

  From Table 6, the batteries shown in Examples 13 to 16 have an improved capacity retention rate after the cycle test, that is, improved cycle characteristics as compared with Examples 4 to 5 and Comparative Example 1. It was confirmed that This is due to the combined effect of the compound represented by the general formula (1) used as an additive and ethylene methane disulfonate or methylene methane disulfonate.

(Example 17)
In Example 8, a nonaqueous electrolyte secondary battery was produced in the same manner as in Example 8, except that the electrolyte solution further contained 1 wt% of ethylenemethane disulfonate. And the characteristic of the battery was investigated similarly to Example 8. The results are shown in Table 7.

(Example 18)
In Example 17, compound no. A nonaqueous electrolyte secondary battery was produced in the same manner as in Example 17 except that the compounds shown in Table 7 were used instead of 2. The battery characteristics were examined in the same manner as in Example 17. The results are shown in Table 7.

(Example 19)
In Example 17, a non-aqueous electrolyte secondary battery was produced in the same manner as in Example 17 except that methylenemethane disulfonate was used instead of ethylenemethane disulfonate. The battery characteristics were examined in the same manner as in Example 17. The results are shown in Table 7.

(Example 20)
In Example 19, compound no. A nonaqueous electrolyte secondary battery was produced in the same manner as in Example 19 except that the compounds shown in Table 7 were used instead of 2. The battery characteristics were examined in the same manner as in Example 19. The results are shown in Table 7.

  From Table 7, the batteries shown in Examples 17 to 20 have an improved capacity retention rate after the cycle test, that is, improved cycle characteristics as compared with Examples 8 to 9 and Comparative Example 3. It was confirmed that This is due to the combined effect of the compound represented by the general formula (1) used as an additive and ethylene methane disulfonate or methylene methane disulfonate.

(Example 21)
In Example 11, a nonaqueous electrolyte secondary battery was produced in the same manner as in Example 11 except that the electrolyte solution further contained 1 wt% of ethylenemethane disulfonate. And the characteristic of the battery was investigated similarly to Example 11. The results are shown in Table 8.

(Example 22)
In Example 21, compound no. A nonaqueous electrolyte secondary battery was produced in the same manner as in Example 21 except that the compounds shown in Table 8 were used instead of 2. And the characteristic of the battery was investigated similarly to Example 21. The results are shown in Table 8.

(Example 22)
In Example 21, a nonaqueous electrolyte secondary battery was produced in the same manner as in Example 21 except that methylenemethane disulfonate was used instead of ethylenemethane disulfonate. And the characteristic of the battery was investigated similarly to Example 21. The results are shown in Table 8.

(Example 23)
In Example 22, compound no. A nonaqueous electrolyte secondary battery was produced in the same manner as in Example 22 except that the compounds shown in Table 8 were used instead of 2. And the characteristic of the battery was investigated similarly to Example 22. The results are shown in Table 8.

  From Table 8, the batteries shown in Examples 21 to 24 have an improved capacity retention rate after the cycle test, that is, improved cycle characteristics as compared with Examples 11 to 12 and Comparative Example 4. It was confirmed that This is due to the combined effect of the compound represented by the general formula (1) used as an additive and ethylene methane disulfonate or methylene methane disulfonate.

(Example 25)
In Example 1, a nonaqueous electrolyte secondary battery was produced in the same manner as in Example 1 except that the electrolyte solution further contained 1 wt% of 1,3-propane sultone. Then, the capacity retention rate (%) was examined in the same manner as in Example 1. The results are shown in Table 9.

(Examples 26 to 27)
In Example 25, Compound No. A nonaqueous electrolyte secondary battery was fabricated in the same manner as in Example 25 except that the compounds shown in Table 9 were used instead of 1. The battery characteristics were examined in the same manner as in Example 25. The results are shown in Table 9.

  From Table 9, the batteries shown in Examples 25 to 27 have an improved capacity retention rate after the cycle test as compared with Examples 1, 4 to 5 and Comparative Examples 1 to 2, that is, cycle characteristics. Has been confirmed to be improved. This is due to the combined effect of the compound represented by the general formula (1) used as an additive and 1,3-propane sultone.

(Example 28)
In Example 7, a nonaqueous electrolyte secondary battery was produced in the same manner as in Example 7 except that the electrolyte solution further contained 1 wt% of 1,3-propane sultone. And the characteristic of the battery was investigated similarly to Example 7. The results are shown in Table 10.

(Examples 29 to 30)
In Example 28, Compound No. A nonaqueous electrolyte secondary battery was fabricated in the same manner as in Example 28 except that the compounds shown in Table 10 were used instead of 1. The battery characteristics were examined in the same manner as in Example 28. The results are shown in Table 10.

  From Table 10, the batteries shown in Examples 28 to 30 have an improved capacity retention rate after the cycle test, that is, improved cycle characteristics compared to Examples 7 to 9 and Comparative Example 3. It was confirmed that This is due to the combined effect of the compound represented by the general formula (1) used as an additive and 1,3-propane sultone.

(Example 31)
In Example 10, a nonaqueous electrolyte secondary battery was fabricated in the same manner as in Example 10 except that the electrolyte solution further contained 1 wt% of 1,3-propane sultone. And the characteristic of the battery was investigated similarly to Example 10. The results are shown in Table 11.

(Examples 32-33)
In Example 31, compound no. A nonaqueous electrolyte secondary battery was produced in the same manner as in Example 31 except that the compounds shown in Table 11 were used instead of 1. And the characteristic of the battery was investigated similarly to Example 31. The results are shown in Table 11.

  From Table 11, the batteries shown in Examples 31 to 33 have an improved capacity retention rate after the cycle test, that is, improved cycle characteristics compared to Examples 10 to 12 and Comparative Example 4. It was confirmed that This is due to the combined effect of the compound represented by the general formula (1) used as an additive and 1,3-propane sultone.

(Example 34)
In Example 10, a nonaqueous electrolyte secondary battery was produced in the same manner as in Example 10 except that 1 wt% of vinylene carbonate (hereinafter also referred to as VC) was further contained in the electrolyte. And the characteristic of the battery was investigated similarly to Example 10. The results are shown in Table 12.

(Examples 35-36)
In Example 34, Compound No. A nonaqueous electrolyte secondary battery was fabricated in the same manner as in Example 34 except that the compounds shown in Table 12 were used instead of 1. The battery characteristics were examined in the same manner as in Example 34. The results are shown in Table 12.

  From Table 12, the batteries shown in Examples 34 to 36 have an improved capacity retention rate after the cycle test, that is, improved cycle characteristics compared to Examples 10 to 12 and Comparative Example 4. It was confirmed that This is due to the combined effect of the compound represented by the general formula (1) used as an additive and vinylene carbonate.

(Example 37)
In Example 10, a nonaqueous electrolyte secondary battery was produced in the same manner as in Example 10 except that the electrolyte solution further contained 1 wt% of vinylene carbonate and 1,3-propane sultone. And the characteristic of the battery was investigated similarly to Example 10. The results are shown in Table 13.

(Examples 38 to 39)
In Example 37, compound no. A nonaqueous electrolyte secondary battery was produced in the same manner as in Example 37 except that the compounds shown in Table 13 were used instead of 1. The battery characteristics were examined in the same manner as in Example 37. The results are shown in Table 13.

  From Table 13, the batteries shown in Examples 37 to 39 have an improved capacity retention rate after the cycle test as compared with Examples 10 to 12, Examples 31 to 36, and Comparative Example 4, that is, It was confirmed that the cycle characteristics were improved. This is due to the combined effect of the compound represented by the general formula (1), vinylene carbonate, and 1,3-propane sultone.

(Example 40)
(Preservation test)
As an additive for the electrolyte, Compound No. Using the compound shown in No. 1, a nonaqueous electrolyte secondary battery similar to that in Example 10 was produced. In this example, the resistance value of the nonaqueous electrolyte secondary battery in storage was measured. First, the produced nonaqueous electrolyte secondary battery was charged and discharged once at 20 ° C. The charging current and discharging current at this time are constant, and the discharging capacity at this time is the initial capacity, and the resistance at that time is the initial resistance. Then, after discharging for 2.5 hours to a predetermined voltage with a constant current and a constant voltage, it was left to stand for 90 days at 45 ° C. or 60 ° C. The discharge operation was performed again at a constant current at room temperature after being left standing, and subsequently, charging and discharging were repeated once again at the same constant current, and the resistance during charging was measured. The initial resistance is 1, and the resistance value after 90 days storage is expressed as a relative value (45 ° C. or 60 ° C. storage) and the capacity retention rate after 60 ° C. storage (discharge capacity after 90 days / initial discharge capacity) The results are shown in Table 14.

(Examples 41 to 42)
Using the compounds shown in Table 14 as additives contained in the electrolytic solution, a non-aqueous electrolyte secondary battery similar to that in Example 40 was produced, and evaluation similar to that in Example 40 was performed. The results are shown in Table 14.

(Comparative Example 5)
A nonaqueous electrolyte secondary battery was produced in the same manner as in Example 40 except that 1,3-propane sultone was used as an additive contained in the electrolyte, and the same evaluation was performed. The results are shown in Table 14.

  As shown in Table 14, the batteries of Examples 40 to 42 were all found to have a suppressed rate of increase in resistance at each temperature as compared with Comparative Example 5 in which 1,3-propane sultone was added. did. In particular, the suppression of resistance increase at 60 ° C. was remarkable. Further, the capacity retention rate is significantly improved as compared with Comparative Example 5.

(Example 43)
In this example, Compound No. 1 was used as an additive for the electrolytic solution. 1 was used to produce the same nonaqueous electrolyte secondary battery as in Example 34, and the same evaluation as in Example 40 was performed. The initial resistance is 1, and the resistance value after 90 days storage is shown as a relative value (45 ° C. or 60 ° C. storage), and the capacity retention rate after 60 ° C. storage (discharge capacity after 90 days / initial discharge capacity) The results are shown in Table 15.

(Examples 44 to 45)
Using the compounds shown in Table 15 as additives, non-aqueous electrolyte secondary batteries were produced in the same manner as in Example 43 and evaluated in the same manner. The results are shown in Table 15.

(Comparative Example 6)
A nonaqueous electrolyte secondary battery was produced in the same manner as in Example 43 except that 1,3-propane sultone was used as an additive contained in the electrolyte, and evaluation was performed in the same manner. The results are shown in Table 15.

  As shown in Table 15, the batteries of Examples 43 to 45 were all found to have a suppressed rate of increase in resistance at each temperature as compared with Comparative Example 6 in which 1,3-propane sultone was added. did. In particular, the suppression of resistance increase at 60 ° C. was remarkable. Further, the capacity retention rate is significantly improved as compared with Comparative Example 6. Compared with Examples 40 to 42, it was confirmed that the resistance increase rate after the storage test was suppressed and that the capacity retention rate was improved, that is, the storage characteristics were improved. This is due to the combined effect of the compound represented by the general formula (1) used as an additive and vinylene carbonate.

11 Positive Electrode Current Collector 12 Layer Containing Positive Electrode Active Material 13 Layer Containing Negative Electrode Active Material 14 Negative Electrode Current Collector 15 Electrolytic Solution 16 Porous Separator

Claims (13)

A nonaqueous electrolytic solution comprising an aprotic solvent, a supporting salt, and any of the disulfonic acid ester compounds represented by the following general formula (1) or (2).
X ₁ -R ₁ -X ₂ (1)
_{X 3 -R 2 -X 4 -R 3} -X 5 (2)
(However, in the above general formulas (1) and (2), X _{1 to} X ₅ are each independently a disulfonate compound represented by the following general formula (3), and R _{1 to} R ₃ are each independently It is a single bond or a substituted or unsubstituted alkylene group having 1 to 5 carbon atoms.)

(However, in the above general formula (3), the binding site of the .R ₁ to R ₃ is a substituted or unsubstituted alkylene group of A ₁ and A ₂ 1 to 5 carbon atoms each independently, A ₁ or A ₂ and Q ₁ each independently represents an oxygen atom, a methylene group or a single bond.)   The nonaqueous electrolytic solution according to claim 1, further comprising one or more compounds having a sulfonyl group in addition to the compound represented by the general formula (1) or (2). The nonaqueous electrolytic solution according to claim 2, comprising a compound represented by the following general formula (4) as the one or more compounds having the sulfonyl group.

(However, the above general formula (4), Q ₂ represents an oxygen atom, a methylene group or a single bond, A ₃ is a substituted or unsubstituted alkylene group having 1 to 5 carbon atoms, a carbonyl group, a sulfinyl group, a carbon number 1 -5 polyfluoroalkylene group, a substituted or unsubstituted fluoroalkylene group having 1 to 5 carbon atoms, or a substituted or unsubstituted alkylene group having 1 to 5 carbon atoms in which at least one CC bond is C-O- A group having a C bond, a group in which at least one C—C bond in the C 1-5 polyfluoroalkylene group is a C—O—C bond, and a substituted or unsubstituted C 1-5 .A ₄ showing a group wherein at least one of the C-C bonds of fluoroalkylene group is selected from the group, which a C-O-C bond, a substituted or unsubstituted alkylene group having 1 to 5 carbon atoms, charcoal Number 1-6 polyfluoroalkylene group, and a substituted or unsubstituted group selected from fluoroalkylene group having 1 to 5 carbon atoms.) The nonaqueous electrolytic solution according to claim 2, wherein the one or more compounds having a sulfonyl group include a sultone compound represented by the following general formula (5).

(However, in the above general formula (5), n is an integer of 0-2. Furthermore, R ₄ to R ₉ is a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, cycloalkyl of 3 to 6 carbon atoms Group, a group selected from aryl groups having 6 to 12 carbon atoms.)   5. The compound represented by the general formula (1) or (2) is contained in an amount of 0.005% by mass to 10% by mass of the entire electrolytic solution. Non-aqueous electrolyte.   The non-aqueous electrolyte according to any one of claims 1 to 5, comprising vinylene carbonate or a derivative thereof.   The aprotic solvent is selected from the group consisting of cyclic carbonates, chain carbonates, aliphatic carboxylic acid esters, γ-lactones, cyclic ethers, chain ethers, and any fluorine derivatives thereof. The nonaqueous electrolytic solution according to any one of claims 1 to 6, further comprising one or two or more solvents. Examples of the supporting salt include LiPF ₆ , LiBF ₄ , LiAsF ₆ , LiSbF ₆ , LiClO ₄ , LiAlCl ₄ , and LiN (C _p F _{2p + 1} SO ₂ ) (C _q F _{2q + 1} SO ₂ ) (p, q are The nonaqueous electrolytic solution according to any one of claims 1 to 7, comprising one or more substances selected from the group consisting of natural numbers).   A nonaqueous electrolyte secondary battery comprising the nonaqueous electrolyte solution according to claim 1, at least a positive electrode, and a negative electrode.   The non-aqueous electrolyte secondary battery according to claim 9, comprising a lithium-containing composite oxide capable of occluding and releasing lithium as a positive electrode active material of the positive electrode.   The non-aqueous electrolyte secondary battery according to claim 10, wherein the lithium-containing composite oxide has a lithium manganese composite oxide having a spinel structure.   As the negative electrode active material of the negative electrode, one or more substances selected from the group consisting of a material capable of inserting and extracting lithium, a lithium metal, a metal material capable of forming an alloy with lithium, and an oxide material are used. The nonaqueous electrolyte secondary battery according to claim 9 or 10, wherein the nonaqueous electrolyte secondary battery is included.   The non-aqueous electrolyte secondary battery according to claim 12, wherein the negative electrode active material includes a carbon material such as graphite or amorphous carbon.

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