JP2013171679A - Nonaqueous battery separator and nonaqueous battery including the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a separator which exhibits stable charge/discharge behavior even when a support with a large hole diameter, such as non woven fabric, capable of achieving higher battery capacity is used, and with which a battery excellent in rate characteristics and overcharge safety can be formed.SOLUTION: A nonaqueous battery separator includes a support containing a particle and a low molecular gelatinizer. A ratio of the number of holes having a minor diameter of 1.0 μm or less among the total hole number included in the support is 20% or less, and a ratio of the number of through holes continuous from one surface to other surface and having a major diameter of 150 μm or more among the total hole number included in the support is 10% or less.

Description

  The present invention relates to a non-aqueous battery separator and a non-aqueous battery using the same.

With the recent development of electronic technology and increasing interest in environmental technology, various electrochemical devices have been developed. In particular, there are many requests for energy conservation, the realization of a distributed energy society, and securing safe and stable energy, and expectations for what can contribute to them are increasing. For example, the power generation device includes a power generation device using natural energy (for example, a solar cell), a fuel cell, and the like, and the power storage device includes a secondary battery, a capacitor, and a capacitor.
Lithium ion secondary batteries, which are typical examples of power storage devices, have been used mainly as rechargeable batteries for small portable devices (notebook computers, mobile phones, etc.) (Patent Document 1). Expansion to is also predicted. In particular, recently, it has been used as a battery for hybrid vehicles and electric vehicles, and is also expected to be used in smart houses. In order for these electrochemical devices to develop, progress and improvement of each member used for them are essential.

Lithium ion secondary batteries generally have a configuration in which a positive electrode and a negative electrode mainly composed of an active material capable of occluding and releasing lithium are arranged via a separator. In the lithium ion secondary battery, the positive electrode is LiCoO ₂ , LiNiO ₂ , LiMn ₂ O ₄ or the like as a positive electrode active material, carbon black or graphite as a conductive agent, polyvinylidene fluoride, latex, rubber, or the like as a binder. Is mixed with a positive electrode current collector made of aluminum or the like. The negative electrode is formed by coating a negative electrode mixture made of copper or the like with a negative electrode mixture in which coke or graphite as a negative electrode active material and polyvinylidene fluoride, latex, rubber, or the like as a binder are mixed. The The separator is made of porous polyolefin or the like, and its thickness is usually very thin, from several μm to several hundred μm. The positive electrode, the negative electrode, and the separator are impregnated with an electrolyte solution in the battery. Examples of the electrolyte solution include lithium salts such as LiPF ₆ and LiBF ₄ , aprotic solvents such as propylene carbonate and ethylene carbonate, An electrolytic solution dissolved in a polymer such as polyethylene oxide is used.

In order to expand the applications of lithium ion secondary batteries, it is necessary to reduce the size and performance of the battery, and one approach is to improve the separator. At present, a microporous membrane made of synthetic resin is mainly used as a separator of a lithium ion secondary battery. A synthetic resin microporous membrane is a highly reliable membrane, but for use as a separator for in-vehicle or large-scale applications, for example, improvements are required in terms of capacity, current density, heat resistance, cost, etc. Yes. As an attempt to improve these performances, there are examples using a separator such as a nonwoven fabric or paper (Patent Documents 2 and 3). Nonwoven fabrics and paper are promising because they can produce a porous film (a film that can increase the capacity of a battery) at a low process cost and can be formed from a material having high heat resistance. In addition, there are examples in which a synthetic resin separator is made porous or low density, and examples in which a process aimed at reducing the manufacturing cost of a synthetic resin separator is studied (Patent Document 4).
Furthermore, there are reports on examples in which a gel electrolyte obtained by gelling an electrolytic solution and a nonwoven fabric separator are combined (Patent Document 5), and examples in which an inorganic thin film composed of an inorganic filler and a binder resin is sputtered onto the nonwoven fabric surface. (Patent Document 6).

JP 2009-087648 A JP 2005-159283 A JP 2005-293891 A JP 2010-244875 A JP 2009-070605 A JP 2001-038442 A

However, when a separator capable of increasing the capacity as described in Patent Documents 2 and 3 is used, various unstable charge / discharge behaviors such as a short circuit and dendrite growth are observed. There is a problem in reliability and safety as separator performance.
Moreover, in the gel electrolyte using a polymer as a gelling agent as described in Patent Document 5, short-circuiting and dendrite growth can be reduced, but battery performance is reduced as compared with a liquid electrolyte solution. It is difficult to make full use of the advantages.
Furthermore, a separator formed with an inorganic thin film on the positive electrode surface of a nonwoven fabric as described in Patent Document 6 has improved oxidation resistance and is expected to improve safety as a battery, but the inorganic thin film forming process is complicated. Yes, from the viewpoint of productivity.

  In view of the above circumstances, the present invention is a battery that exhibits stable charge / discharge behavior even when using a support having a large pore diameter such as a nonwoven fabric capable of increasing the capacity of the battery, and has excellent rate characteristics and overcharge safety. It aims at providing the separator which can form.

  As a result of intensive studies to achieve the above-mentioned object, the present inventors have used a material having a specific pore structure as a support, and a non-aqueous battery obtained by supporting a low-molecular gelling agent and particles on the support. It has been found that the separator for a battery exhibits stable charge / discharge behavior in a non-aqueous battery using the separator, and is excellent in rate characteristics and overcharge safety, and has completed the present invention.

That is, the present invention is as follows.
[1]
A separator for a non-aqueous battery comprising a support containing particles and a low-molecular gelling agent,
The ratio of the number of holes having a minor axis of 1.0 μm or less out of the total number of holes of the support is 20% or less, and the total number of holes of the support is changed from one surface to the other surface. A separator for a nonaqueous battery in which the ratio of the number of continuous through-holes having a major axis of 150 μm or more is 10% or less.
[2]
The separator for nonaqueous batteries according to the above [1], wherein the particles include inorganic particles.
[3]
The separator for a nonaqueous battery according to the above [1] or [2], wherein the particles contain a metal oxide.
[4]
The non-aqueous battery according to any one of [1] to [3], wherein the particles include at least one selected from the group consisting of aluminum oxide, boehmite, calcined kaolin, titanium oxide, zinc oxide, and magnesium oxide. Separator.
[5]
The separator for a nonaqueous battery according to any one of the above [1] to [4], wherein the average primary particle diameter of the particles is 10 nm or more and 10 μm or less.
[6]
The separator for nonaqueous batteries according to any one of the above [1] to [5], wherein the particles have a fractal structure.
[7]
The separator for nonaqueous batteries according to any one of [1] to [6], wherein the support has an air permeability of 50 s / 100 cc or less.
[8]
The separator for nonaqueous batteries according to any one of the above [1] to [7], wherein the ratio of the number of holes having a minor axis of 200 μm or more out of the total number of holes of the support is 5% or less.
[9]
For non-aqueous batteries according to any one of [1] to [8] above, wherein the ratio of the number of holes having a minor axis of 1.0 μm or less among the holes present on the outermost surface of the support is 5% or less. Separator.
[10]
The separator for nonaqueous batteries according to any one of [1] to [9], wherein the support has a thickness of 20 μm or more and 60 μm or less.
[11]
The separator for nonaqueous batteries according to any one of the above [1] to [10], wherein the support is a nonwoven fabric.
[12]
The separator for nonaqueous batteries according to any one of the above [1] to [11], which is obtained by impregnating the support with a nonaqueous solvent containing the low molecular gelling agent and the particles.
[13]
The non-aqueous battery separator according to any one of the above [1] to [12], wherein the low-molecular gelling agent comprises one or more compounds selected from the group consisting of the following general formulas (1) and (2): .
^{Rf 1 -R 1 -X 1 -L 1} -R 2 (1)
Rf ¹ -R ¹ -X ¹ -L ¹ -R ³ -L ² -X ² -R ⁴ -Rf ² (2)
(In the formulas (1) and (2),
Rf ¹ and Rf ² each independently represents a perfluoroalkyl group having 2 to 20 carbon atoms, and R ¹ and R ⁴ each independently represents a single bond or a divalent saturated hydrocarbon group having 1 to 6 carbon atoms. X ¹ and X ² each independently represent a divalent functional group selected from the group consisting of the following formulas (1a) to (1g), and L ¹ and L ² each independently represent a single bond or an alkyl group. Alternatively, an oxyalkylene group optionally substituted with a halogen atom, an alkyl group, an oxycycloalkylene group optionally substituted with a halogen atom, or a divalent oxyaromatic optionally substituted with an alkyl group or a halogen atom shows a family group, R ² is an alkyl group or a halogen atom (excluding a fluorine atom.) in the optionally substituted alkyl group having 1 to 20 carbon atoms, an alkyl group or A fluoroalkyl group, an aryl group or a fluoroaryl group which may be substituted with a rogen atom (excluding a fluorine atom), or one or more of these groups and a divalent group corresponding to these groups 1 represents a monovalent group bonded to one or more of the groups, R ³ may have one or more oxygen and / or sulfur atoms in the main chain, and is substituted with an alkyl group; And a C1-C18 divalent saturated hydrocarbon group. )

[14]
Wherein X ¹ and X ² are each independently the above-described formula (1a) or said a divalent functional group represented by formula (1d), the [13] The non-aqueous battery separator according.
[15]
Wherein X ¹ and X ² is a divalent functional group represented by the formula (1d), the [13] or [14] Non-aqueous battery separator according.
[16]
The separator for a non-aqueous battery according to any one of [1] to [15], wherein the low-molecular gelling agent and a part of the particles are present in the pores of the support.
[17]
The separator for nonaqueous batteries according to any one of the above [1] to [16] and at least one material selected from the group consisting of materials capable of occluding and releasing lithium ions as a positive electrode active material. A positive electrode, a negative electrode containing at least one material selected from the group consisting of lithium and a material capable of inserting and extracting lithium ions as a negative electrode active material, and a metal lithium; a non-aqueous solvent; and a lithium salt Non-aqueous battery.
[18]
The nonaqueous battery according to [17], wherein the positive electrode includes a lithium-containing compound as the positive electrode active material.
[19]
The negative electrode contains, as the negative electrode active material, at least one material selected from the group consisting of metallic lithium, a carbon material, a material containing an element capable of forming an alloy with lithium, and a lithium-containing compound. 17] or the nonaqueous battery according to [18].

  According to the present invention, a non-aqueous battery that exhibits stable charge / discharge behavior even when using a support having a large pore size, such as a nonwoven fabric, capable of increasing the capacity of the battery, and that has excellent rate characteristics and overcharge stability. Separator and a non-aqueous battery using the same can be provided.

It is sectional drawing which shows roughly an example of the nonaqueous battery in this embodiment.

  Hereinafter, a mode for carrying out the present invention (hereinafter simply referred to as “the present embodiment”) will be described in detail. The non-aqueous battery separator in the present embodiment is a non-aqueous battery separator including a support containing particles and a low-molecular gelling agent, and the short diameter of the total number of holes of the support is 1. The ratio of the number of holes of 0 μm or less is adjusted to 20% or less, and among the total number of holes that the support has, the long diameter of the through holes continuous from one surface to the other surface is 150 μm or more Is adjusted to 10% or less.

<Support>
The nonaqueous battery in this embodiment includes a separator including a support between the positive electrode and the negative electrode from the viewpoint of providing safety such as prevention of short circuit between the positive and negative electrodes and shutdown. As the support, an insulating thin film having high ion permeability and excellent mechanical strength is preferable.

  Examples of the material of the support in the present embodiment include ceramic, glass, resin, and cellulose. The resin may be a synthetic resin or a natural resin (natural polymer), and may be an organic resin or an inorganic resin, but tends to have excellent performance as a support. Therefore, an organic resin is preferable. Examples of the organic resin include polyolefin, polyester, polyamide, and heat resistant resins such as liquid crystal polyester and aramid. The material of the support is preferably ceramic and glass from the viewpoint of high heat resistance, and polyester, polyamide, liquid crystal polyester, aramid, and cellulose are preferable from the viewpoint of handling and heat resistance. Further, the material of the support is preferably polyolefin from the viewpoints of cost and processability. Among these materials, when a resin is employed, a homopolymer resin or a copolymer resin may be used, or a mixture of a plurality of types of resins and an alloy may be used.

  Further, the support may be a laminate in which films of a plurality of materials are laminated. When the support is a laminate, the material of each layer may be the same or different. When producing a support for a laminate, it may be produced in order by repeating the formation of one layer on another layer, that is, it may be produced by successively multilayering, and a plurality of membranes produced separately are bonded together. Thus, a laminate may be produced.

  The form of the support in the present embodiment includes, for example, a synthetic resin microporous membrane produced by forming a synthetic resin film, a fiber spun from a synthetic resin or a natural polymer, a woven fabric processed from glass fiber or ceramic fiber , Nonwoven fabrics, knitted fabrics, papermaking, and films prepared by arranging fine particles of synthetic resin, ceramic particles and glass. Among these, woven fabric, non-woven fabric, and paper making are preferable, non-woven fabric and paper making are more preferable, and non-woven fabric is particularly preferable, from the viewpoint of ease of forming a pore structure peculiar to the present embodiment and cost. Moreover, these supports can be produced by a general production method, and the production method is not particularly limited. In the case of a nonwoven fabric, the support in this embodiment can be produced by, for example, a spunbond method, a melt blown method, or the like.

  The support may be obtained by stacking a plurality of films produced by a plurality of production methods, or may be obtained by sequentially multilayering by a plurality of production methods.

  The support in this embodiment has a specific pore structure. Specifically, among the total number of holes of the support, the ratio of the number of holes having a minor axis of 1.0 μm or less is 20% or less, and one of the total number of holes of the support is one surface. To the other surface, the ratio of the number of holes having a long diameter of 150 μm or more continuous through holes is 10% or less.

  In the support of the present embodiment, the ratio of the number of holes having a minor axis of 1.0 μm or less is preferably 10% or less, and more preferably 0.5% or more. Further, the ratio of the number of holes having a minor axis of 200 μm or more is more preferably 5% or less, and the ratio of the number of holes having a minor axis of 150 μm or more is more preferably 5% or less. As a result of the ratio of the number of pores having a minor axis of 1.0 μm or less out of the total number of holes of the support being 20% or less, the low molecular gelling agent and the particles are satisfactorily filled into the support, The stability of the charge / discharge behavior of the nonaqueous battery and the overcharge safety can be improved.

  Furthermore, out of the total number of holes of the support in the present embodiment, the ratio of the number of holes having a long diameter of 150 μm or more continuous from one surface to the other surface is 10% or less, preferably through holes The ratio of the number of holes having a major axis of 150 μm or more is 5% or less. When the ratio of holes having a long diameter of 150 μm or more is 10% or less, unstable charge / discharge behavior such as occurrence of a short circuit tends to be further suppressed.

  Moreover, it is preferable that the ratio of the number of holes having a minor axis of 1.0 μm or less among the holes present on the outermost surface of the support in the present embodiment is 5% or less. When the ratio of the number of holes having a minor axis of 1.0 μm or less among the holes present on the outermost surface of the support is 5% or less, the load characteristics tend to be excellent.

  The pore structure and pore diameter of the support can be controlled by a known production method in the field of the support. For example, when the support is made of synthetic resin, it can be controlled by changing the conditions for film formation and stretching. When the support is a woven fabric or a knitted fabric, it can be controlled by selecting a fiber and setting a loom or knitting machine. In the case of a nonwoven fabric, it can be controlled by the fiber diameter and film forming conditions.

  The air permeability of the support in the present embodiment is preferably 50 s / 100 cc or less, more preferably 20 s / 100 cc or less. When the air permeability of the support is 50 s / 100 cc or less, the load characteristics tend to be excellent.

  The film thickness of the support in the present embodiment is preferably 20 μm or more and 60 μm or less, more preferably 20 μm or more and 50 μm or less. The film thickness of the support is preferably 20 μm or more from the viewpoint of mechanical strength and from the viewpoint of isolating the positive and negative electrodes and suppressing short circuits. Moreover, it is preferable that it is 60 micrometers or less from a viewpoint of raising the output density as a battery and suppressing the fall of an energy density.

  The minor axis and the major axis of the support can be determined by the method described in Examples described later. The ratio of the number of holes having a short diameter of 1.0 μm or less, the ratio of the number of holes having a short diameter of 200 μm or more, and the ratio of the number of holes having a short diameter of 150 μm or more of the total number of holes of the support is All can be obtained by the method described in the examples described later. Further, among the holes existing on the outermost surface of the support, the ratio of the number of holes having a minor axis of 1.0 μm or less, and the total number of holes of the support, the through-holes continuous from one surface to the other surface The ratio of the number of holes having a major axis of 150 μm or more can also be determined by the method described in Examples described later.

  The air permeability of the support is the time required for 100 cc of air to permeate. An air permeability tester is used for measuring the air permeability of the support. In the present embodiment, the air permeability of the support is a value measured with a Gurley air permeability meter in accordance with JIS P-8117.

  In this embodiment, the film thickness of a support body can be calculated | required by the method as described in the Example mentioned later.

<Particle>
The separator for a non-aqueous battery in this embodiment includes particles in the support from the viewpoints of preventing internal short circuit, ensuring the strength of the separator, and retaining the electrolyte solution. The particles contained in the support in the present embodiment are preferably present inside and / or on the surface of the support. By using the support having the specific pore structure as described above in combination with the particles, a part of the particles are filled into the large pore diameter unique to the support. As a result, in the non-aqueous battery using the separator of the present embodiment, charging / discharging instability due to local concentration of current density locally on a part of the electrode can be suppressed, and the non-aqueous battery is made of lithium ion. In the case of a battery and a lithium battery, lithium dendrite growth can be inhibited, internal short circuit can be suppressed, and excess charge electric capacity due to minute short circuit can be improved, and overcharge safety can be enhanced. When insulating (non-conductive) particles are present inside and / or on the surface of the support, it is possible to obtain a separator for a non-aqueous battery that is excellent in liquid retention, conductivity, and strength of the electrolytic solution. Moreover, it is also preferable in that the specific functions of the particles themselves such as heat resistance and flame retardancy can be imparted to the separator.

  The particles contained in the support are not particularly limited as long as they are non-conductive and chemically and electrochemically stable with respect to the battery constituent material. Inorganic particles, organic particles, polymer particles, organic Any of inorganic composite particles may be used. From the viewpoint of cost and electrochemical stability, the particles preferably include inorganic particles, more preferably include metal oxides, and aluminum oxide, boehmite, calcined kaolin, titanium oxide, zinc oxide, and magnesium oxide are further included. Aluminum oxide is preferable, and aluminum oxide is particularly preferable.

  From the viewpoint of imparting a shutdown function to the separator, organic particles can also be included as particles. Examples of the organic particles include polymer particles. Examples of the polymer particles include polyolefins such as polyethylene and polypropylene, and copolymers and derivatives containing the same, acid esters such as cross-linked polyacrylic acid esters and cross-linked polymethacrylic acid esters, and copolymers containing the same, and cross-linking. Examples thereof include particles made of polystyrene.

  The average primary particle diameter of the particles is preferably 10 nm or more and 10 μm or less, more preferably 10 nm or more and 1 μm or less. When the average primary particle diameter is 10 nm or more, the aggregate tends to be easily crushed, and a particle production method has been established, which is preferable. When the average primary particle size is 10 μm or less, the support is easily filled with particles, and therefore, more excellent short-circuit prevention and overcharge safety effects tend to be obtained.

  The average primary particle diameter of the particles can be obtained from the number average value of the primary particle diameters of particles randomly extracted from a sample by observation using a transmission electron microscope. The particle shape of the particles may be spherical or non-spherical. The primary particle diameter in the case of non-spherical is the average value of the major axis diameter and minor axis diameter measured with a scale. Although it does not specifically limit, It is preferable that the particle | grains which have a fractal structure are contained. The particle having a fractal structure indicates a fractal dimension that is an index of self-similarity or a particle having an inherent network structure, and the fractal dimension is more preferably in a range of 1.5 to 2.1. Since such particles have a low bulk density and form a particle network with a small addition amount, when the support having a large pore diameter in this embodiment is applied as a separator for a nonaqueous battery, the effect of filling the through holes is obtained. Therefore, it is preferable.

  The fractal dimension of the particle should be analyzed from the slope of the scattering intensity-scattering vector curve obtained from the light scattering measurement as described in, for example, “J. Rheol. Vol. 37, 1225 to 1235, published in 1993”. Can do.

<Low molecular gelling agent>
The separator in the present embodiment includes a low molecular gelling agent in the support in addition to the above particles from the viewpoints of membrane reinforcement, charge / discharge assist, and heat resistance improvement. The low molecular weight gelling agent refers to a non-polymer type gelling agent capable of sol-gel transition by reversible physical interaction. Various low molecular gelling agents are known, and any of them may be used. For example, the compounds described in “Chem. Rev. 97, p3133-p3159, published in 1997” and “Acc. Chem. Res. 39, p489-497, published in 2006” are described. Compounds, compounds described in JP-A-10-175901, compounds described in International Publication No. 2006/82768, compounds described in JP-A-2007-506833, JP-A-2009-15592 And the like.

The low molecular gelling agent in the present embodiment is selected from the group consisting of compounds represented by the following general formulas (1) and (2) from the viewpoint of electrochemical stability and gelling ability with respect to the electrolyte solution. It is preferable that 1 or more types are included.
^{Rf 1 -R 1 -X 1 -L 1} -R 2 (1)
Rf ¹ -R ¹ -X ¹ -L ¹ -R ³ -L ² -X ² -R ⁴ -Rf ² (2)

In the general formulas (1) and (2), Rf ¹ and Rf ² each independently represents a C 2-20 perfluoroalkyl group. The compound having 2 to 20 carbon atoms can be easily obtained and synthesized. From the viewpoints of the mixing of the compounds represented by the above general formulas (1) and (2) (hereinafter also referred to as “perfluoro compounds”) into the electrolyte, the electrochemical characteristics of the electrolyte, and the gelling ability, Rf ¹ and Rf ² preferably have 2 to 12 carbon atoms. Examples of the perfluoroalkyl group include perfluoroethyl group, perfluoro n-propyl group, perfluoroisopropyl group, perfluoro n-butyl group, perfluoro t-butyl group, perfluoro n-hexyl group, perfluoro n. -An octyl group, a perfluoro n-decyl group, and a perfluoro n-dodecyl group are mentioned.

In the general formulas (1) and (2), R ¹ and R ⁴ each independently represent a single bond or a divalent saturated hydrocarbon group having 1 to 6 carbon atoms, and the carbon number is 2 to 5. It is preferable. When the divalent saturated hydrocarbon group has 3 or more carbon atoms, it may or may not be branched. Examples of such a divalent saturated hydrocarbon group include a methylidene group, an ethylene group, an n-propylene group, an isopropylene group, and an n-butene group.

In the general formulas (1) and (2), X ¹ and X ² each independently represent a divalent functional group selected from the group consisting of the following formulas (1a) to (1g). Among these, from an electrochemical viewpoint, a divalent functional group selected from the group consisting of the following formulas (1a), (1b) and (1d) is preferable, and is represented by the following formula (1a) or (1d). The divalent functional group is more preferably a divalent functional group represented by the following formula (1d).

In the above general formulas (1) and (2), L ¹ and L ² are each independently substituted with a single bond, an alkyl group or an oxyalkylene group optionally substituted with a halogen atom, an alkyl group or a halogen atom. An oxycycloalkylene group which may be substituted, or a divalent oxyaromatic group which may be substituted with an alkyl group or a halogen atom (-OAr-; Ar is a divalent aromatic group); Examples of the oxyalkylene group include an oxyalkylene group having 2 to 10 carbon atoms, more specifically, an oxyethylene group (—C ₂ H ₄ O—) and an oxypropylene group (—C ₃ H ₆ O—). Can be mentioned. Examples of the oxycycloalkylene group include an oxycycloalkylene group having 5 to 12 carbon atoms, and more specifically, an oxycyclopentylene group, an oxycyclohexylene group, and an oxydicyclohexylene group.

  Among these, a divalent oxyaromatic group which may be substituted with an alkyl group or a halogen atom is preferable from the viewpoint of gelling ability and safety improvement of the electrolytic solution. The divalent aromatic group in the divalent oxyaromatic group which may be substituted with an alkyl group or a halogen atom is a cyclic divalent group exhibiting so-called “aromaticity”. The divalent aromatic group may be a carbocyclic group or a heterocyclic group. The carbocyclic group has 6 to 30 nuclear atoms and may be substituted with an alkyl group or a halogen atom as described above. Specific examples of the divalent aromatic group include, for example, a nucleus represented by a phenylene group, a biphenylene group, a terphenylene group, a naphthylene group, an anthranylene group, a phenanthrylene group, a pyrenylene group, a chrysenylene group, and a fluoranthenylene group. A divalent group is mentioned.

  The heterocyclic group has 5 to 30 nuclear atoms, and has 2 nuclei such as a pyrrolene group, a furylene group, a thiophenylene group, a triazolen group, an oxadiazolene group, a pyridylene group, and a pyrimidylene group. Valent groups. Among these, as the divalent aromatic group, a phenylene group, a biphenylene group, or a naphthylene group is preferable.

  Examples of the alkyl group as a substituent include a methyl group and an ethyl group, and examples of the halogen atom include a fluorine atom, a chlorine atom, and a bromine atom. Furthermore, the oxycycloalkylene group and the oxyaromatic group include those in which a plurality of rings are connected, and examples of such a group include an oxybiphenylene group, an oxyterphenylene group, and an oxycycloalkylphenylene group. .

R ² in the general formula (1) is an alkyl group having 1 to 20 carbon atoms, an alkyl group, or a halogen atom (provided that it may be substituted with an alkyl group or a halogen atom (excluding a fluorine atom)). A fluoroalkyl group, an aryl group, or a fluoroaryl group optionally substituted with a fluorine atom), or one or more of these groups and one of divalent groups corresponding to these groups A monovalent group bonded to a species or more is shown. More specifically, R ² is methyl group, ethyl group, n-propyl group, n-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, n-decyl. C1-C12 alkyl groups, such as group, are mentioned. These alkyl groups may be further substituted with an alkyl group or a halogen atom (excluding a fluorine atom).

  As a fluoroalkyl group, a C1-C12 fluoroalkyl group is preferable. Specific examples of the fluoroalkyl group having 1 to 12 carbon atoms include a trifluoromethyl group, 1,1,1,2,2-pentafluoroethyl group, 1,1,2,2-tetrafluoroethyl group, 1,1,1,2,2,3,3-heptafluoro n-butyl group, 1,1,2,2,3,3,4,4,5,5,6,6-dodecafluoro n-hexyl Groups and 1,1,1,2,2,3,3,4,4,5,5,6,6-tridecafluoro n-decyl groups. The fluoroalkyl group may be further substituted with an alkyl group or a halogen atom (excluding a fluorine atom).

  Examples of the aryl group include aryl groups having 6 to 12 nuclear atoms such as a phenyl group, a biphenyl group, and a naphthyl group. Examples of the fluoroaryl group include a monofluorophenyl group, a difluorophenyl group, and a tetrafluoro group. Examples thereof include a fluoroaryl group having 6 to 12 nucleus atoms such as a phenyl group.

R ² represents one or more of the aforementioned alkyl group, fluoroalkyl group, aryl group and fluoroaryl group, and a divalent group corresponding to these groups, that is, an alkylene group, a fluoroalkylene group, an arylene group. A monovalent group in which one or more of a group and a fluoroarylene group are bonded may be used. Examples of such a group include a group in which an alkylene group and a perfluoroalkyl group are bonded (however, this group is also a kind of fluoroalkyl group), a group in which an alkylene group and an aryl group are bonded, fluoro Examples include a group in which an alkyl group and a fluoroarylene group are bonded.

R ² is preferably an alkyl group or a fluoroalkyl group from the viewpoint of more effectively and reliably achieving the effects of the present invention, and is an alkyl group having 1 to 12 carbon atoms or a fluoroalkyl group having 1 to 12 carbon atoms (provided that Or a perfluoroalkyl group having 1 to 12 carbon atoms, more preferably an alkyl group having 1 to 8 carbon atoms or a fluoroalkyl group having 2 to 10 carbon atoms (provided that perfluoro More preferably, the alkyl group is excluded.

R ³ in the general formula (2) may have one or more oxygen and / or sulfur atoms in the main chain, and may be substituted with an alkyl group. Represents a saturated saturated hydrocarbon group. The carbon number is preferably 1 to 16, and more preferably 2 to 14. The gelling ability can also be controlled by the number of carbon atoms in R ³ . Moreover, it is preferable that it is the carbon number of the said range from a viewpoint of synthetic | combination and the ease of raw material acquisition.

Examples of the gelling agent having a perfluoro group include Rf ¹ -R ¹ —O—R ² , Rf ¹ —R ¹ —S—R ² , Rf ¹ —R ¹ —SO ₂ —R ² , Rf ¹ —. R ¹ —OCO—R ² , Rf ¹ —R ¹ —O—Ar—O—R ² (wherein Ar represents a divalent aromatic group; the same shall apply hereinafter), Rf ¹ —R ¹ —SO ₂ —Ar—O—R ² , Rf ¹ —R ¹ —SO ₂ —Ar—O—Rf ⁴ , Rf ¹ —R ¹ —SO ₂ —Ar—O—Rf ³ —Rf ⁴ (where Rf ³ represents fluoro An alkylene group, Rf ⁴ represents a fluoroalkyl group.), Rf ¹ -R ¹ -SO-Ar-O-R ² , Rf ¹ -R ¹ -S-Ar-O-R ² , Rf ¹ -R ^1- O—R ⁵ —O—R ² (where R ⁵ represents an alkylene group), Rf ¹ —R ¹ —CONH—R ² , Rf ¹ —R ¹ —SO ₂ —Ar ¹ —O—R ³ -O-Ar ² -SO _2- R ⁴ -Rf ² (wherein Ar ¹ and Ar ² each independently represents a divalent aromatic group; the same shall apply hereinafter), Rf ¹ -R ¹ -O-Ar ¹ -O-R ³ —O—Ar ² —O—R ⁴ —Rf ² , Rf ¹ —R ¹ —SO ₂ —Ar ¹ —O—R ⁶ —O—R ⁷ —O—Ar ² —O—R ⁴ —Rf ² (here And R ⁶ and R ⁷ each independently represents an alkylene group, the same shall apply hereinafter). More specifically, Rf ¹ and Rf ² are each independently a perfluoroalkyl group having 2 to 10 carbon atoms, R ¹ is an alkylene group having 2 to 4 carbon atoms, Ar is (or Ar ¹ and Ar ² are each Independently, a p-phenylene group or a p-biphenylene group, a compound represented by each of the above general formulas wherein R ² is an alkyl group having 4 to 8 carbon atoms, and a dimer structure thereof, for example, Rf ¹ -R ^1- O—Ar—O—R ² , Rf ¹ —R ¹ —SO ₂ —Ar—O—R ² , Rf ¹ —R ¹ —O—Ar ¹ —O—R ³ —O—Ar ² —O— R ⁴ —Rf ² , Rf ¹ —R ¹ —SO ₂ —Ar ¹ —O—R ⁶ —O—R ⁷ —O—Ar ² —O—R ⁴ —Rf ² are exemplified. It is done. The low molecular gelling agent mentioned above is used individually by 1 type or in combination of 2 or more types.

  Among the gelling agents in the present embodiment, those having a perfluoro group include, for example, International Publication No. 2007/083843, JP2007-191626A, JP2007-191627A and JP2007. It can manufacture with reference to the method of 191661.

Moreover, the gelling agent which has a perfluoro group in this embodiment is compoundable with the following scheme, for example.
That is, first, a compound represented by the following formula (II) is synthesized as follows from a compound represented by the following formula (I) available as a commercial product. The compound 4-hydroxy-4′-mercaptophenyl represented by the formula (I) may be replaced with 4-hydroxy-4′-mercaptobiphenyl. In the following description, 4-hydroxy-4′-mercaptophenyl is used. An example using is shown.

  Next, the compound represented by the formula (II) is dimerized as follows to obtain the compound represented by the formula (III).

In this case, as the compound represented by the formula (II), compounds having different carbon numbers of the perfluoroalkyl group may be used (for example, one n is replaced with a different numerical value m), and R ¹ May be changed to R ³ which is a different divalent hydrocarbon group. However, since they do not necessarily react at a molar ratio of 1: 1, it is preferable to use the same compound as the compound represented by formula (II) from the viewpoint of stably obtaining a desired compound. .

  Here, the compound represented by the formula (III) has a gelling ability. However, as shown in the following reaction formula, the compound represented by the following formula (IV) can be obtained by oxidizing the thioether moiety to sulfonylation or sulfoxide formation. A gelling agent having the perfluoro group represented is obtained.

In the production scheme of the gelling agent having a perfluoro group represented by the general formula (IV), n represents an integer of 2 to 18, and R ¹ and R ³ are each independently a single bond or a main chain. Represents a substituted or unsubstituted divalent hydrocarbon group having 1 to 6 carbon atoms, and R ² is a substituted or unsubstituted carbon group having 3 to 18 carbon atoms which may have an ether group or a thioether group. Represents a substituted divalent hydrocarbon group, and each X independently represents an SO group or an SO ₂ group.

Furthermore, the gelling agent having a perfluoro group in the present embodiment can be synthesized by the following scheme, for example. First, a thiol compound represented by the following general formula (11a) is sulfided with a compound represented by the following general formula (11b) in the presence of a base such as triethylamine in a solvent such as dry THF. The compound represented by (11c) is obtained.
HS-Ar-OH (11a)
C _m F _{2m + 1} C _p H _2p X ¹ (11b)
_{C m F 2m + 1 C p} H 2p -S-Ar-OH (11c)

Next, the compound represented by the general formula (11c) is etherified with a compound represented by the following general formula (11d) in the presence of an alkali metal compound such as K ₂ CO _{3 in} a solvent such as 3-pentanone. To obtain a compound represented by the following general formula (11e).
R ¹ X ² (11d)
_{C m F 2m + 1 C p} H 2p -S-Ar-O-R 1 (11e)

Then, by oxidizing the compound represented by the general formula (11e) with an oxidizing agent such as hydrogen peroxide in the presence of a catalyst such as acetic acid, a perfluoro compound represented by the following general formula (11j) is obtained. can get.
_{C m F 2m + 1 C p} H 2p -SO 2 -Ar-O-R 1 (11j)
Here, in the production scheme of the perfluoro compound represented by the general formula (11j), Ar represents a substituted or unsubstituted divalent aromatic group having 8 to 30 nuclear atoms, and R ¹ is saturated or unsaturated. A saturated monovalent hydrocarbon group having 1 to 20 carbon atoms, m represents a natural number of 2 to 16, and p represents an integer of 0 to 6. X ¹ represents a halogen atom such as an iodine atom, and X ² represents a halogen atom such as a bromine atom.

  As the above synthesis method, for example, the synthesis method described in International Publication No. 2009/78268 can be referred to.

When Ar is a group in which a plurality of aromatic rings such as a biphenylene group or a triphenylene group are bonded by a single bond, the perfluoro compound represented by the general formula (11j) can be obtained by, for example, the following synthesis method. it can. First, a thiol compound represented by the following general formula (11f) is sulfided with a compound represented by the above general formula (11b) in the presence of a base such as triethylamine in a solvent such as dry THF. A compound represented by (11 g) is obtained. Here, in the formulas (11f) and (11g), m and p are as defined in the formula (11j), X ³ represents a halogen atom such as a bromine atom, and Ar ² represents the above formula (11j). ) Represents a part of the divalent aromatic hydrocarbon group constituting Ar.
^{HS-Ar 2 -X 3 (11f} )
_{C m F 2m + 1 C p} H 2p -S-Ar 2 -X 3 (11g)

Next, the following compound (11h) is obtained by oxidizing the compound represented by the general formula (11g) with an oxidizing agent such as hydrogen peroxide in the presence of a catalyst such as acetic acid. Here, in the formula (11h), Ar ² , X ³ , m and p are as defined in the formula (11g).
_{C m F 2m + 1 C p} H 2p -SO 2 -Ar 2 -X 3 (11h)

Then, from the compound represented by the above general formula (11h) and the compound represented by the following general formula (11i), in the presence of a palladium catalyst in a basic aqueous solution such as K ₂ CO ₃ , Suzuki-Miyaura coupling To obtain the perfluoro compound represented by the general formula (11j). Here, in the formula (11i), R ¹ has the same meaning as in the formula (11j), Ar ³ is Ar ² a divalent aromatic hydrocarbon group constituting Ar in the formula (11j) A part different from is shown, and Ar ² and Ar ³ bonded by a single bond is Ar.
R ¹ —O—Ar ³ —B (OH) ₂ (11i)

Moreover, the gelling agent which has a perfluoro group in this embodiment is compoundable with the following scheme, for example. That is, from the compound represented by the following general formula (Ia) and the compound represented by the following general formula (IIa), dehydration condensation such as Mitsunobu reaction is a kind of gelling agent having a perfluoro group. A compound represented by the formula (IIIa) can be synthesized. Here, in the formula, Y ¹ and Y ² each independently represent an S atom or an O atom.
^{Rf 1 -R 1 -Y 1 -Z-} Y 2 H (Ia)
Rf ² R ² OH (IIa)
^{Rf 1 -R 1 -Y 1 -Z-} Y 2 -R 2 -Rf 2 (IIIa)

Further, in the compound represented by the above general formula (IIIa), when Y ¹ and / or Y ² is an S atom, the S atom is further sulfonylated or sulfoxided to form a gel having a perfluoro group A compound represented by the following general formula (IVa), which is another kind of agent, can be synthesized. Here, at least one of Y ³ and Y ⁴ is an SO group or SO ₂ group, and when one of Y ³ and Y ⁴ is an SO group or SO ₂ group, the other is an S atom or an O atom.
^{Rf 1 -R 1 -Y 3 -Z-} Y 4 -R 2 -Rf 2 (IVa)

The compound represented by the general formula (Ia) is, for example, a perfluoroalkane halide (thiol group or a hydrogen atom of a hydroxyl group) of a compound represented by the following formula (Va) under alkaline conditions ( For example, it can be synthesized by substitution with a perfluoroalkyl group of iodide.
HY ¹ -ZY ² H (Va)
The compound represented by the above formula (IIa) can be synthesized by further reducing the halide of alkanol obtained by the addition reaction of perfluoroalkane halide (for example, iodide) to alkenol.

Here, in the scheme for producing the perfluoro compound represented by the general formula (IIIa) or (IVa), Rf ¹ and Rf ² are each independently substituted or unsubstituted having 2 to 18 carbon atoms in the main chain. Represents a perfluoroalkyl group, R ¹ and R ² each independently represents a single bond or a substituted or unsubstituted divalent hydrocarbon group having 1 to 8 carbon atoms in the main chain, and Z represents a substituted or unsubstituted group. Represents a divalent aromatic hydrocarbon group or alicyclic hydrocarbon group having 5 to 30 nuclear atoms.

  However, the synthesis method of the gelling agent having a perfluoro group in the present embodiment is not limited to the above method.

  The low molecular gelling agent in the present embodiment is contained in the support, and it is preferable that a part of the low molecular gelling agent adheres to the surface of the support, is impregnated in the electrode, or exists in the pores of the support. . For example, when the support is a non-woven fabric, the entire pores of the non-woven fabric or a part of the non-woven fabric is filled with the low-molecular gelling agent, thereby causing problems such as destabilization of charge and discharge of the battery due to the size of the pore diameter peculiar to the non-woven fabric. In addition, the nonuniformity of the pore size distribution can be improved. In particular, when the non-aqueous battery is a lithium ion battery or a lithium battery, internal short circuit between the electrodes due to expansion and contraction of the positive electrode and the negative electrode due to charging / discharging, or internal due to lithium dendrite generated due to current density non-uniformity. Short circuit can be prevented and stable charge / discharge characteristics tend to be exhibited.

  The separator in this embodiment can be obtained, for example, by impregnating the support with a non-aqueous solvent containing a low molecular gelling agent and particles. Specifically, a slurry in which particles and a low-molecular gelling agent are dispersed in a non-aqueous solvent, or a slurry in which a low-molecular gelling agent is dissolved and dispersed in a non-aqueous solvent is impregnated with a support. The slurry can be applied to a support. As the non-aqueous solvent, it is preferable to use an electrolytic solution solvent or an electrolytic solution because a separator can be prepared and a battery can be produced at the same time.

  As described above, the non-aqueous battery separator in the present embodiment is excellent in charge / discharge stability and can be used as a separator for various non-aqueous batteries. Among them, lithium ion is particularly preferably used as a separator that contributes to charging / discharging, for example, a lithium ion battery, a lithium battery, a lithium ion capacitor, or the like. The separator in the present embodiment may contain other components such as a polymer such as polyacrylonitrile, polymethyl methacrylate, and polyvinylidene fluoride in addition to the support, particles, and low molecular gelling agent.

  The nonaqueous battery in the present embodiment includes the separator, an electrolytic solution, a positive electrode, and a negative electrode.

<Electrolyte>
The electrolytic solution in this embodiment contains (I) a nonaqueous solvent and (II) an electrolyte.
(I) As a nonaqueous solvent, various things can be used, For example, an aprotic solvent is mentioned. When used as an electrolyte of a lithium ion secondary battery, it is preferable to use an aprotic polar solvent in order to increase the degree of ionization of a lithium salt that is an electrolyte that contributes to the charge and discharge. Specific examples of the non-aqueous solvent include ethylene carbonate, propylene carbonate, 1,2-butylene carbonate, trans-2,3-butylene carbonate, cis-2,3-butylene carbonate, 1,2-pentylene carbonate, trans- Cyclic carbonates such as 2,3-pentylene carbonate, cis-2,3-pentylene carbonate, trifluoromethylethylene carbonate, fluoroethylene carbonate and 4,5-difluoroethylene carbonate; such as γ-butyrolactone and γ-valerolactone Lactone; Cyclic sulfone such as sulfolane; Cyclic ether such as tetrahydrofuran and dioxane; Methyl ethyl carbonate, dimethyl carbonate, diethyl carbonate, methyl propyl carbonate, methyl isopropyl Chain carbonates such as carbonate, dipropyl carbonate, methylbutyl carbonate, dibutyl carbonate, ethylpropyl carbonate and methyltrifluoroethyl carbonate; nitriles such as acetonitrile; chain ethers such as dimethyl ether; chain carboxylic acids such as methyl propionate Examples of esters include chain ether carbonate compounds such as dimethoxyethane. These are used singly or in combination of two or more.

  (I) The non-aqueous solvent preferably contains one or more cyclic aprotic polar solvents in order to increase the ionization degree of the electrolyte. From the same viewpoint, (I) the nonaqueous solvent more preferably contains one or more cyclic carbonates such as ethylene carbonate and propylene carbonate. The cyclic compound has a high dielectric constant and tends to help ionize the electrolyte and increase the gelation ability.

(II) Although it does not specifically limit as electrolyte, When a nonaqueous battery is a lithium ion battery, a lithium battery, or a lithium capacitor, lithium salt is used. Specific examples of the lithium salt used as the electrolyte include, for example, LiPF ₆ , LiBF ₄ , LiClO ₄ , LiAsF ₆ , Li ₂ SiF ₆ , LiOSO ₂ C _k F _{2k + 1} (k is an integer of 1 to 8), LiN (SO ₂ C _k F _{2k + 1} ) ₂ [k is an integer of 1 to 8], LiPF _n (C _k F _{2k + 1} ) _6-n [n is an integer of 1 to 5, k is 1 to 8 Integer], LiBF _n ((C _k F _{2k + 1} ) _4-n [n is an integer of 1 to 3, k is an integer of 1 to 8], lithium bisoxalyl represented by LiB (C ₂ O ₂ ) ₂ Examples thereof include borate, lithium difluorooxalylborate represented by LiBF ₂ (C ₂ O ₂ ), and lithium trifluorooxalyl phosphate represented by LiPF ₃ (C ₂ O ₂ ).

Moreover, the lithium salt represented by the following general formula (a), (b), or (c) can also be used as an electrolyte.
LiC (SO ₂ R ¹¹ ) (SO ₂ R ¹² ) (SO ₂ R ¹³ ) (a)
LiN (SO ₂ OR ¹⁴ ) (SO ₂ OR ¹⁵ ) (b)
LiN (SO ₂ R ¹⁶ ) (SO ₂ OR ¹⁷ ) (c)
Here, in the formula, R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ , R ¹⁶ and R ¹⁷ may be the same or different from each other, and are a C 1-8 perfluoroalkyl group. Indicates.

These electrolytes are used singly or in combination of two or more. Among these electrolytes, LiPF ₆ , LiBF ₄ and LiN (SO ₂ C _k F _{2k + 1} ) ₂ [k is an integer of 1 to 8] are used from the viewpoint of enhancing gelation ability in addition to battery characteristics and stability. preferable.

  The concentration of the electrolyte is arbitrary and is not particularly limited, but the electrolyte is preferably contained in the electrolytic solution at a concentration of 0.1 to 3 mol / liter, more preferably 0.5 to 2 mol / liter.

  The electrolyte solution in the present embodiment can further contain an additive as necessary. Examples of the additive include a heat stabilizer, a flame retardant, a thermal runaway inhibitor, an overcharge suppression additive, a thickener, an emulsifier, a reinforcing agent, and an additive for forming an electrode protective film. These additives may be solid (bulk), powder, or liquid. Moreover, even if it melt | dissolves in electrolyte solution, it may not melt | dissolve.

  The addition amount of the additive is selected in a range that does not hinder the achievement of the object of the present invention and can achieve the purpose of use of the additive, and aims to achieve both battery characteristics and the effect of the additive. Therefore, the content of the additive is preferably 0.5 parts by mass to 20 parts by mass and more preferably 1 part by mass to 10 parts by mass with respect to 100 parts by mass of the total amount of the solvent and the electrolyte. preferable. Similarly, before removing at least a part of the solvent, the additive is preferably added in an amount of 0.025 parts by mass to 18 parts by mass with respect to 100 parts by mass of the total amount of the solvent and the electrolyte.

  It is preferable that the electrolyte solution in this embodiment contains the particle | grains and / or low molecular gelling agent which are contained in a separator. If the electrolyte contains particles and / or a low molecular gelling agent, the support can be impregnated with the particles and the low molecular gelling agent simply by pouring the electrolyte into a pre-assembled battery. Therefore, there is an advantage that battery manufacture is simplified. The particles and low-molecular gelling agent contained in the electrolyte solution may be the same as or different from the particles and low-molecular gelling agent contained in the separator. .

  When particles are included in the electrolytic solution, the content of the particles is arbitrary, but the content ratio with respect to the nonaqueous solvent is 0.5: 99.5 to 10:90 on a mass basis. It is preferable that the ratio is 1:99 to 5:95. Moreover, it exists in the tendency for both gelling ability and handling property to become favorable because the content ratio of the said component exists in the said range. In addition, as the content of the particles in the electrolytic solution is larger, the electrolytic solution becomes a stronger gel, and as the content of the particles is smaller, the viscosity of the electrolytic solution is lower and the handling becomes easier.

  When the low molecular gelling agent is contained in the electrolytic solution, the content of the low molecular gelling agent is arbitrary, but the content ratio with respect to the nonaqueous solvent is 0 on the mass basis. : 1: 99.9 to 10:90 is preferable, and 0.3: 99.7 to 5:95 is more preferable. When the content ratio of these components is within the above range, the lithium ion secondary battery using the electrolytic solution tends to exhibit particularly high battery characteristics. Moreover, it exists in the tendency for both gelling ability and handling property to become favorable because the content ratio of the said component exists in the said range. In addition, as the content of the gelling agent in the electrolytic solution increases, the electrolytic solution becomes a solid gel with a high phase transition point, and as the content of the gelling agent decreases, the viscosity of the electrolytic solution decreases and becomes easier to handle. .

  When the electrolytic solution of the present embodiment contains a low molecular gelling agent, it is preferably an electrolytic solution or a gelled electrolytic solution in which the low molecular gelling agent is dissolved, and is a phase that becomes a gel at a low temperature and a sol at a high temperature. More preferably, it is a transition type gel electrolyte solution. In the nonaqueous battery according to the present embodiment, when the electrolytic solution is a gel electrolyte solution, the handling property such as injection is excellent, and the safety such as the reduction of leakage tends to be secured at a high level. Among them, the phase transition temperature between the gel and the sol is more preferably in the range of 50 to 150 ° C.

  The mixing ratio of the non-aqueous solvent, the electrolyte, the particles, and the low-molecular gelling agent can be selected according to the purpose, but the electrolyte concentration, the particle content, and the low-molecular gelling agent content are all within the preferred ranges described above. Furthermore, it is desirable that it is in a more preferable range. By producing an electrolytic solution with such a composition, battery characteristics and handleability can be further improved.

<Positive electrode>
In the lithium ion secondary battery in the present embodiment, as the positive electrode, a material containing at least one material selected from the group consisting of materials capable of inserting and extracting lithium ions is used as the positive electrode active material. Examples of materials capable of inserting and extracting lithium ions include composite oxides represented by the following general formulas (6a) and (6b), metal chalcogenides and metal oxides having a tunnel structure and a layered structure, and olivine Type phosphoric acid compounds.
Li _x MO ₂ (6a)
Li _y M ₂ O ₄ (6b)
Here, in the formula, M represents one or more metals selected from transition metals, x represents a number from 0 to 1, and y represents a number from 0 to 2.

More specifically, for example, lithium cobalt oxide such as LiCoO ₂ ; lithium manganese oxide such as LiMnO ₂ , LiMn ₂ O ₄ and Li ₂ Mn ₂ O ₄ ; lithium nickel oxide such as LiNiO ₂ ; Li _z MO ₂ (M represents two or more elements selected from the group consisting of Ni, Mn, Co, Al, and Mg, and z represents a number greater than 0.9 and less than 1.2.) Metal oxide; iron phosphate olivine represented by LiFePO ₄ may be mentioned. Further, as the positive electrode active material, for example, oxides of metals other than lithium such as S, MnO ₂ , FeO ₂ , FeS ₂ , V ₂ O ₅ , V ₆ O ₁₃ , TiO ₂ , TiS ₂ , MoS _2, and NbSe ₂ are used. Are also illustrated. Furthermore, conductive polymers such as polyaniline, polythiophene, polyacetylene, and polypyrrole are also exemplified as the positive electrode active material.

In the lithium ion secondary battery in the present embodiment, the positive electrode preferably includes a lithium-containing compound as a positive electrode active material. When a lithium-containing compound is used as the positive electrode active material, high voltage and high energy density tend to be obtained. As such a lithium-containing compound, any compound containing lithium may be used. For example, a composite oxide containing lithium and a transition metal element, a phosphate compound containing lithium and a transition metal element, and a lithium and transition metal element (For example, Li _{t Mu} SiO ₄ , where M is as defined in the above formula (6a), t is a number from 0 to 1, and u is a number from 0 to 2). . From the viewpoint of obtaining a higher voltage, lithium, cobalt (Co), nickel (Ni), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), chromium (Cr), vanadium ( V) and composite oxides containing at least one transition metal element selected from the group consisting of titanium (Ti) and phosphate compounds are preferred.

More specifically, the lithium-containing compound is preferably a lithium-containing metal oxide, a lithium-containing metal chalcogenide, or a lithium-containing phosphate metal compound. For example, in the following general formulas (7a) and (7b), And the compounds represented.
^{_{Li v M I O 2 (7a}} )
Li _w M ^II PO ₄ (7b)
Here, in the formula, M ^I and M ^II each represent one or more transition metal elements, and the values of v and w vary depending on the charge / discharge state of the battery, but usually v is 0.05 to 1.10, w Indicates a number from 0.05 to 1.10.

  The compound represented by the general formula (7a) generally has a layered structure, and the compound represented by the general formula (7b) generally has an olivine structure. In these compounds, for the purpose of stabilizing the structure, a part of the transition metal element is substituted with Al, Mg, other transition metal elements or included in the crystal grain boundary, a part of the oxygen atom And those substituted with a fluorine atom or the like. Furthermore, what coat | covered the other positive electrode active material to at least one part of the positive electrode active material surface is mentioned.

  A positive electrode active material is used individually by 1 type or in combination of 2 or more types.

  The number average particle diameter (primary particle diameter) of the positive electrode active material is preferably 0.05 μm to 100 μm, more preferably 1 μm to 10 μm. The number average particle size of the positive electrode active material can be measured by a wet particle size measuring device (for example, a laser diffraction / scattering particle size distribution meter, a dynamic light scattering particle size distribution meter). Alternatively, 100 particles observed with a transmission electron microscope are randomly extracted and analyzed with image analysis software (for example, image analysis software manufactured by Asahi Kasei Engineering Co., Ltd., trade name “A Image-kun”). It can also be obtained by calculating an average. In this case, when the number average particle diameter differs between measurement methods for the same sample, a calibration curve created for the standard sample may be used.

  A positive electrode is obtained as follows, for example. That is, first, a positive electrode mixture-containing paste is prepared by dispersing, in a solvent, a positive electrode mixture obtained by adding a conductive additive, a binder, or the like to the positive electrode active material as necessary. Next, this positive electrode mixture-containing paste is applied to a positive electrode current collector and dried to form a positive electrode mixture layer, which is pressurized as necessary to adjust the thickness, thereby producing a positive electrode. Here, the solid content concentration in the positive electrode mixture-containing paste is preferably 30 to 80% by mass, and more preferably 40 to 70% by mass. The positive electrode current collector is made of, for example, a metal foil such as an aluminum foil or a stainless steel foil.

<Negative electrode>
In the lithium ion secondary battery in the present embodiment, the negative electrode uses one or more materials selected from the group consisting of a material capable of occluding and releasing lithium ions as a negative electrode active material and metallic lithium. The negative electrode preferably contains, as a negative electrode active material, one or more materials selected from the group consisting of metallic lithium, a carbon material, a material containing an element capable of forming an alloy with lithium, and a lithium-containing compound. Examples of such materials include lithium metal, hard carbon, soft carbon, artificial graphite, natural graphite, graphite, pyrolytic carbon, coke, glassy carbon, organic polymer compound fired body, mesocarbon microbeads. Carbon materials such as carbon fiber, activated carbon, graphite, carbon colloid, and carbon black. Among these, examples of the coke include pitch coke, needle coke, and petroleum coke. Further, the fired body of the organic polymer compound is obtained by firing and polymerizing a polymer material such as a phenol resin or a furan resin at an appropriate temperature. In the present embodiment, a battery employing metallic lithium as the negative electrode active material is also included in the lithium ion secondary battery.

  Further, examples of the material capable of inserting and extracting lithium ions include a material containing an element capable of forming an alloy with lithium. This material may be a single metal or semi-metal, an alloy or a compound, and may have at least a part of one or more of these phases. .

  In the present specification, the “alloy” includes an alloy having one or more metal elements and one or more metalloid elements in addition to an alloy composed of two or more metal elements. In addition, the alloy may have a nonmetallic element as long as the alloy has metallic properties as a whole. In the alloy structure, a solid solution, a eutectic (eutectic mixture), an intermetallic compound, or two or more of these coexist.

  Examples of such metal elements and metalloid elements include titanium (Ti), tin (Sn), lead (Pb), aluminum, indium (In), silicon (Si), zinc (Zn), and antimony (Sb). Bismuth (Bi), gallium (Ga), germanium (Ge), arsenic (As), silver (Ag), hafnium (Hf), zirconium (Zr) and yttrium (Y).

  Among these, metal elements and metalloid elements of Group 4 or 14 in the long-period periodic table are preferable, and titanium, silicon, and tin are particularly preferable.

  As an alloy of tin, for example, as a second constituent element other than tin, silicon, magnesium (Mg), nickel, copper, iron, cobalt, manganese, zinc, indium, silver, titanium (Ti), germanium, bismuth, Examples thereof include those having one or more elements selected from the group consisting of antimony and chromium (Cr).

  Examples of the silicon alloy include, as the second constituent element other than silicon, tin, magnesium, nickel, copper, iron, cobalt, manganese, zinc, indium, silver, titanium, germanium, bismuth, antimony, and chromium. Those having one or more elements selected from the above are listed.

  Examples of the titanium compound, the tin compound, and the silicon compound include those having oxygen (O) or carbon (C), and in addition to titanium, tin, or silicon, the second constituent element described above is included. It may be.

  Moreover, a lithium containing compound is also mentioned as a material which can occlude and release lithium ions. As the lithium-containing compound, the same compounds as those exemplified as the positive electrode material can be used.

  A negative electrode active material is used individually by 1 type or in combination of 2 or more types.

  The number average particle diameter (primary particle diameter) of the negative electrode active material is preferably 0.1 μm to 100 μm, more preferably 1 μm to 10 μm. The number average particle size of the negative electrode active material is measured by the same method as the number average particle size of the positive electrode active material.

  A negative electrode is obtained as follows, for example. That is, first, a negative electrode mixture-containing paste is prepared by dispersing, in a solvent, a negative electrode mixture prepared by adding a conductive additive or a binder to the negative electrode active material, if necessary. Next, the negative electrode mixture-containing paste is applied to a negative electrode current collector and dried to form a negative electrode mixture layer, which is pressurized as necessary to adjust the thickness, thereby producing a negative electrode. Here, the solid content concentration in the negative electrode mixture-containing paste is preferably 30 to 80% by mass, and more preferably 40 to 70% by mass. The negative electrode current collector is made of, for example, a metal foil such as a copper foil, a nickel foil, or a stainless steel foil.

  Examples of the conductive aid used as necessary in the production of the positive electrode and the negative electrode include carbon black such as graphite, acetylene black and ketjen black, and carbon fiber. The number average particle size (primary particle size) of the conductive assistant is preferably 0.1 μm to 100 μm, more preferably 1 μm to 10 μm, and is measured by the same method as the number average particle size of the positive electrode active material. Examples of the binder include polyvinylidene fluoride (PVDF), a copolymer containing polyvinylidene fluoride, polytetrafluoroethylene (PTFE), polyacrylic acid, styrene butadiene rubber, and fluorine rubber.

  The nonaqueous battery in the present embodiment is not particularly limited, and is, for example, a lithium ion secondary battery. FIG. 1 is a schematic cross-sectional view of an example of a lithium ion secondary battery. A lithium ion secondary battery 100 shown in FIG. 1 includes a support 110 containing particles and a low-molecular gelling agent, a positive electrode 120 and a negative electrode 130 that sandwich the support 110 from both sides, and a positive electrode that sandwiches the laminate. A current collector 140 (arranged outside the positive electrode), a negative electrode current collector 150 (arranged outside the negative electrode), and a battery exterior 160 that accommodates them are provided. A laminate in which the positive electrode 120, the support 110, and the negative electrode 130 are laminated is impregnated with an electrolytic solution. As each of these members, if the support including the electrolyte solution, the particles, and the low molecular gelling agent is combined as described above, the other members should be those provided in the conventional lithium ion secondary battery. For example, it may be as described above.

<Production method of battery>
The nonaqueous battery in the present embodiment is manufactured by a known method using the above-described specific separator, an electrolytic solution, a positive electrode, and a negative electrode. For example, a separator is interposed between a plurality of positive electrodes and negative electrodes that are alternately stacked by forming a positive electrode and a negative electrode into a laminate with a support interposed between them, or bending or laminating them. Or molded into a laminate. Next, the laminated body is accommodated in a battery case (exterior), the electrolytic solution used in the present embodiment is injected into the case, and the laminated body is immersed in the electrolytic solution and sealed. A non-aqueous battery can be produced. The shape of the non-aqueous battery is not particularly limited, and for example, a cylindrical shape, an elliptical shape, a rectangular tube shape, a button shape, a coin shape, a flat shape, and a laminate shape are suitably employed.

  As mentioned above, although the form for implementing this invention was demonstrated, this invention is not limited to the said embodiment. The present invention can be variously modified without departing from the gist thereof.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to these Examples. Various characteristics of the lithium ion secondary battery were measured and evaluated as follows.

(I) Measurement of hole diameter of support The hole diameter of the support used for evaluation was measured with a digital microscope. Keyence VHX-500F (trade name) is used for the digital microscope, and the entire range of separators used for battery evaluation is observed with a field of view of 300 times. Among 1000 holes, the short diameter is 1.0 μm. The number of the following holes was measured. From the number of the holes, the ratio of the number of holes having a minor axis of 1.0 μm or less out of 1000 holes was obtained. The said ratio was made into the ratio of the number of the holes whose minor axis is 1.0 micrometer or less among the total number of holes which a support body has.
Similarly, the ratio of the number of holes having a minor axis of 200 μm or more was similarly determined by measuring the number of holes having a minor axis of 200 μm or more among arbitrary 1000 holes.
In addition, among the holes existing on the outermost surface of the support, the ratio of the number of holes having a minor axis of 1.0 μm or less, and the total number of holes of the support, the continuous penetration from one surface to the other surface Similarly, the ratio of the holes whose major axis is 150 μm or more is the same, and the number of holes whose minor axis is 1.0 μm or less and the number of holes whose major axis is 150 μm or more among arbitrary 1000 holes. It was calculated | required by measuring.

  Moreover, the short diameter and long diameter of the hole of the nonwoven fabric which is a support body were defined as follows. When the holes of the nonwoven fabric are triangular, the major axis is the length of the longest line segment connecting the midpoints of the two sides, and the minor axis is the shortest segment of the line segments connecting the midpoints of the two sides. Defined as length. When the hole of the nonwoven fabric was a quadrangle, the longest line segment among the line segments connecting the midpoints of the opposite sides was defined as the major axis, and the shortest segment was defined as the minor axis. When the holes of the nonwoven fabric were polygonal, the major axis was defined as the longest vertex distance, and the minor axis was defined as the shortest vertex distance.

(Ii) Measurement of air permeability of support The air permeability of the support was measured with a Gurley type air permeability meter in accordance with JIS P-8117.

(Iii) Film thickness of support The film thickness of the support was measured using a film thickness meter. As a film thickness meter, a Digimatic indicator manufactured by Mitutoyo was used to measure the film thickness at three arbitrary points in the support, and the average value was taken as the film thickness of the support.

(Iv) Charging and Discharging Capacity Measurement of Lithium Ion Secondary Battery The charging and discharging characteristics of the lithium ion secondary battery were evaluated by measuring the charging capacity and discharging capacity at specific charging current and discharging current as follows.
As a lithium ion secondary battery for measurement, a small battery with 1C = 3 mA was prepared and used. The charge and discharge capacity of the lithium ion secondary battery was measured using a charge / discharge device ACD-01 (trade name) manufactured by Asuka Electronics Co., Ltd. and a thermostat PLM-63S (trade name) manufactured by Futaba Kagaku Co., Ltd.
(Measurement 1) After charging at a constant current of 1 mA and reaching 4.2 V, charging was performed at a constant voltage of 4.2 V for a total of 8 hours. Thereafter, after a pause of 10 minutes, the discharge capacity when discharged to 3.0 V at 1 mA was measured.
(Measurement 2) Subsequently, after charging at a constant current of 3 mA and reaching 4.2 V, charging was performed at a constant voltage of 4.2 V for a total of 3 hours. Then, after 10 minutes of rest, the discharge capacity was measured when discharged to 3.0 V at 3 mA. The battery ambient temperature at this time was set to 25 ° C.

(Iv-A) Charging / discharging efficiency measurement The charging / discharging measurement 1 as described in said (iv) charge and discharge capacity measurement of a lithium ion secondary battery was performed once, and charging / discharging of the measurement 2 was performed 4 times after that. The charge / discharge efficiency for the fourth time was calculated by the following formula. In addition, it can be said that it is excellent in battery characteristics, so that the value of this charging / discharging efficiency is large (it is excellent in charging / discharging behavior).
Charge / discharge efficiency (%) = (capacity during discharge / capacity during charge) × 100

(Iv-i) Voltage change during rest The voltage change during rest for 10 minutes from the fourth charge to the fourth discharge was monitored. A smaller voltage change indicates a more stable battery.

(V) Load characteristics of lithium ion secondary battery The load characteristics of the lithium ion secondary battery were measured and evaluated as follows.
After measuring the above (iv-a) charge / discharge efficiency, the battery was charged at a constant current of 3 mA, reached 4.2 V, and then charged at a constant voltage of 4.2 V for a total of 3 hours. After 10 minutes of rest, the discharge capacity when discharged to 3.0 V at a constant current was measured. The discharge capacity was measured at discharge currents of 3.0 mA, 6.0 mA, 9.0 mA, 15 mA, and 30 mA. The battery ambient temperature at this time was set to 25 ° C. The load characteristics of each battery were evaluated using a discharge capacity retention ratio represented by a ratio obtained by dividing the discharge capacity when discharged at each current value by the discharge capacity when discharged at 3.0 mA. In addition, it can be said that it is a battery excellent in load characteristics, so that the value of this discharge capacity maintenance factor is large.
Discharge capacity retention rate (%) = (discharge capacity at each current value / discharge capacity at 3.0 mA) × 100

(Vi) Evaluation of Charging Behavior (Initial Charging Characteristics) of Laminate Type Single Layer Lithium Ion Secondary Battery The charging behavior of the laminate type single layer lithium ion secondary battery was evaluated as follows. As a lithium ion secondary battery for measurement, a single-layer laminated battery with 1C = 48.0 mA was prepared and used. The measurement was performed using a charge / discharge device ACD-01 (trade name) manufactured by Asuka Electronics Co., Ltd. After charging at a constant current of 15.0 mA and reaching 4.2 V, charging was performed for a total of 8 hours while changing the current value so as to be a constant voltage of 4.2 V, and evaluation was performed as follows. The battery ambient temperature at this time was set to 25 ° C.
×: A voltage drop occurred while charging at a constant current, and the battery did not reach 4.2V ○: A battery that reached a voltage of 4.2V and could be charged at a constant voltage ◎: A voltage of 4 Battery that has reached 2V and has rapidly converged under constant voltage charging

(Vii) Evaluation of Charging Behavior (Initial Charging Characteristics) of Laminated Laminated Lithium Ion Secondary Battery The charging / discharging behavior of the laminated laminated lithium ion secondary battery was evaluated as follows. As a lithium ion secondary battery for measurement, a laminate type laminated lithium ion secondary battery with 1C = 720 mA was prepared and used. The measurement was performed using a charge / discharge device ACD-01 (trade name) manufactured by Asuka Electronics Co., Ltd.
(Measurement 1) After charging with a constant current of 380 mA and reaching 4.2 V, charging was performed at a constant voltage of 4.2 V for a total of 5 hours. Then, after 10 minutes of rest, the battery was discharged at 380 mA to 3.0 V. The charge / discharge test of measurement 1 was conducted a total of 3 times, and the following evaluations were made.
X: A voltage drop occurred during charging at a constant current and did not reach 4.2 V. ○: A voltage drop occurred during the first constant current charge, but the constant voltage was applied in the second and subsequent charging / discharging. ◎: A voltage drop occurred during the first constant current charge, but it was possible to charge at a constant voltage in the second and subsequent charge and discharge, and the current converged quickly. Batteries

(Viii) Laminate type laminated lithium ion secondary battery overcharge test (existence of rupture and ignition)
In the overcharge test, a laminated laminated lithium ion secondary battery with 1C = 720 mA was prepared and used. The measurement was performed using a charge / discharge device ACD-01 (trade name) manufactured by Asuka Electronics Co., Ltd. The battery charged to a charging rate of 100% was further charged at a constant current of 720 mA. The battery voltage during charging was monitored, and the charging rate at which a voltage drop was observed was determined. The fact that a voltage drop is observed means that a short circuit has occurred. Further, after the test was completed, the appearance of the lithium ion secondary battery was observed to confirm the presence or absence of rupture and ignition.

(Synthesis Example 1)
As a gelling agent, a compound represented by the following structural formula (I) (hereinafter also referred to as “compound (I)”. The same shall apply hereinafter) was synthesized as follows.

First, compound (a) was obtained according to the following scheme. Specifically, in a 200 mL eggplant flask, a solution of 29.89 g (63 mmol) of 2- (perfluorohexyl) ethyl iodide and 11.34 g ((60 mmol) of p-bromothiophenol (100 mmol) in a 100 mL solution of dry tetrahydrofuran (dryTHF). Then, 9.09 g (90 mmol) of triethylamine was added, and the mixture was refluxed for 10 hours in an oil bath at 84 ° C. After returning to room temperature, a solid was confirmed in the solution, and thus the solid was removed by suction filtration.
After the filtrate was transferred to a 300 mL separatory funnel, cyclopentyl methyl ether was added, the organic layer was washed twice with water, and anhydrous magnesium sulfate was added to the organic layer and dried. Anhydrous magnesium sulfate was removed by fold filtration. The obtained filtrate was concentrated under reduced pressure, and the residue was recrystallized from ethanol. As a result, 31.87 g of compound (a) was obtained (yield 99.3%).

  Next, the compound (b) was obtained according to the following scheme. Specifically, in a 300 mL eggplant flask, 13 mL (151 mmol) of 35% aqueous hydrogen peroxide was added to 100 mL of a glacial acetic acid solution of 32.82 g (61.3 mmol) of the above compound (a), and the oil bath at 70 ° C. Stirring was performed for 2 hours. After returning to room temperature, 5 mL of 20% aqueous sodium hydrogen sulfite solution was added to reduce unreacted hydrogen peroxide. At this time, a solid had already precipitated in the solution, but when 90 mL of water was added, a solid further precipitated. After performing suction filtration, the solid was washed with water. As a result, 26.34 g of compound (b) was obtained (yield 75%).

Furthermore, the compound (I) was obtained according to the following scheme. Specifically, in a 100 mL eggplant flask, 1.39 g (6.58 mmol) of 4-hexoxyphenylboronic acid, 3.7 g (6.58 mmol) of compound (b), 30 mL of 2M aqueous sodium carbonate solution, dioxane 60 mL (amount added until solid dissolved) was added. To this was added 0.295 g (1.31 mmol) of palladium acetate and 1.18 g (4.5 mmol) of triphenylphosphine, and then a Dimroth tube was attached to the eggplant flask, and vigorously at 95 ° C. for 2.5 hours under N ₂ atmosphere. Stir. After cooling to room temperature, 50 mL of water was added and stirred at room temperature for 2.5 hours. After transferring to a 300 mL separatory funnel, 80 mL of ethyl acetate was added as an organic solvent, and the aqueous layer was removed. This aqueous layer was extracted twice with 50 mL of ethyl acetate. These organic layers were combined and washed once with 120 mL of saturated aqueous sodium hydrogen carbonate solution and twice with saturated brine. After the organic layer was transferred to a 200 mL Erlenmeyer flask, 0.2 g of activated carbon was added and stirred at room temperature for 30 minutes. Further, sodium sulfate was added and stirred at room temperature for 1 hour.
Celite was spread to a depth of 1 cm in Nutsche, and the solid was removed by suction filtration using the celite. The filtrate was transferred to a 200 mL eggplant flask and then concentrated under reduced pressure to obtain a solid (c). Petroleum ether (20 mL) and methanol (30 mL) were added to the solid (c), but they were not completely dissolved. The filtrate was concentrated under reduced pressure to give a solid (e). As a result of measuring ¹ H-NMR spectra of the solids (d) and (e), it was found that the main component of the solid (d) was the target product. When the solid (d) was dissolved in chloroform, black microcrystals were confirmed in the solution, and the microcrystals were removed by passing through a cylinder filter (pore diameter 0.45 μm, diameter 13 mm). The solution passed through the filter was concentrated under reduced pressure and recrystallized with chloroform. In order to increase the yield, the filtrate after recrystallization was concentrated under reduced pressure and recrystallized twice with chloroform and ethanol. As a result of recrystallization three times in total, 2.38 g of compound (I) was obtained (yield 54%).
The structure of the obtained compound (a) was confirmed by ¹ H-NMR (CDCl ₃ ). The results were as follows.
¹ H-NMR (CDCl ₃ ) 0.92 (3H, m), 1.48 (6H, m), 1.81 (2H, m), 2.65 (2H, m), 3.33 (2H, m), 4.02 (2H, m), 7.01 (2H, d, J = 8.0 Hz), 7.56 (2H, d, J = 8.0 Hz), 7.76 (2H, d, J = 8.0 Hz), 7.95 (2H, d, J = 8.0 Hz) ppm

(Synthesis Example 2)
As a gelling agent, the following compound (b) was synthesized by the same procedure as in Synthesis Example 1.
The structure of the obtained compound (b) was confirmed by ¹ H-NMR (CDCl ₃ ). The results were as follows.
¹ H-NMR (CDCl ₃ ) 0.88 (3H, m), 1.48 (10H, m), 1.80 (2H, m), 2.65 (2H, m), 3.35 (2H, m), 4.01 (2H, m), 7.01 (2H, d, J = 8.0 Hz), 7.56 (2H, d, J = 8.0 Hz), 7.76 (2H, d, J = 8.0 Hz), 7.94 (2H, d, J = 8.0 Hz) ppm

(Production Example 1)
<Preparation of electrolyte>
Ethylene carbonate and methyl ethyl carbonate were mixed at a volume ratio of 1: 2 to obtain a mixed solution. LiPF ₆ was added to this mixed solution at 1 mol / L to prepare a mother electrolyte (A) (hereinafter, the electrolyte before adding particles and a gelling agent is referred to as “mother electrolyte”).
Aluminum oxide particles having an average primary particle size of 13 nm (trade name: AEROXIDE Alu C805, manufactured by Evonik Co., Ltd.) are added to the mother electrolyte (A), and the rotational speed is determined using a defoaming kneader manufactured by Nippon Seiki Seisakusho. The particles were mixed for 10 minutes at 1500 rpm. Thereafter, the compound (b) is added as a gelling agent, heated to 90 ° C. and uniformly mixed, and then cooled to 25 ° C. to obtain an electrolytic solution (a) containing 1% by mass of aluminum oxide and the gelling agent. Obtained.

(Production Example 2 to Production Example 7)
Hereinafter, the amount of aluminum oxide particles and the kind and amount of the low-molecular gelling agent are added to the mother electrolyte (A) so as to have the contents shown in Table 1 (based on the total amount of the electrolyte). Electrolytes (b), (c), (d), (e), (f) and (g) were prepared by the same procedure as in Production Example 1, respectively.

Example 1
<Preparation of positive electrode>
Lithium nickel, manganese and cobalt mixed oxide having a number average particle diameter of 11 μm as a positive electrode active material, graphite carbon powder having a number average particle diameter of 6.5 μm and acetylene black powder having a number average particle diameter of 48 nm as a conductive auxiliary agent, and a binder Polyvinylidene fluoride (PVDF) as a mixed oxide: graphite carbon powder: acetylene black powder: PVDF = 100: 4.2: 1.8: 4.6. N-methyl-2-pyrrolidone was added to the obtained mixture so as to have a solid content of 68% by mass and further mixed to prepare a slurry solution. This slurry-like solution was applied to one side of an aluminum foil having a thickness of 20 μm, and the solvent was dried and removed, followed by rolling with a roll press. The rolled product was punched into a disk shape having a diameter of 16 mm to obtain a positive electrode (α).

<Production of negative electrode>
Graphite carbon powder I having a number average particle diameter of 12.7 μm and graphite carbon powder II having a number average particle diameter of 6.5 μm as a negative electrode active material, a carboxymethylcellulose solution (solid content concentration 1.83% by mass) as a binder, and a diene system Rubber (glass transition temperature: −5 ° C., number average particle size upon drying: 120 nm, dispersion medium: water, solid content concentration 40% by mass), graphite carbon powder I: graphite carbon powder II: carboxymethyl cellulose solution: diene A rubber-like rubber was mixed at a solid content mass ratio of 90: 10: 1.44: 1.76 so that the total solid content concentration was 45% by mass to prepare a slurry solution. The slurry solution was applied to one side of a 10 μm thick copper foil, and the solvent was removed by drying, followed by rolling with a roll press. The rolled product was punched into a disk shape with a diameter of 16 mm to obtain a negative electrode (β).

<Preparation of support>
A nonwoven fabric made of polyethylene terephthalate (film thickness: 32 μm, basis weight: 19 g / m ² ) was selected as a support and punched into a disk shape having a diameter of 24 mm to obtain a support (γ). The pore diameter and air permeability of the obtained support were measured as described above.

<Battery assembly>
A laminate in which the positive electrode (α) and the negative electrode (β) produced as described above were superimposed on both sides of the support (γ) was inserted into a SUS disk type battery case. Next, 0.5 mL of the electrolytic solution (a) heated to 90 ° C. was injected into the battery case, and the laminate was immersed in the electrolytic solution (a). Thereafter, the battery case was sealed to produce a lithium ion secondary battery (small battery). The lithium ion secondary battery was held at 80 ° C. for 1 hour, and then cooled to 25 ° C. to obtain a lithium ion secondary battery (1).
By using such a manufacturing method, preparation of a separator and production of a battery can be performed simultaneously.
In addition, as a result of disassembling the produced lithium ion secondary battery (1) and observing with a digital microscope, it has confirmed that the separator which contains particle | grains and a gelatinizer in a support body was able to be prepared. The support was observed with a 500 × field of view using a KEYENCE digital microscope, VHX-500F (trade name).

(Examples 2 and 3)
Lithium ion secondary batteries (2) and (3) were obtained in the same manner as in Example 1 except that the support and the electrolytic solution were changed as shown in Table 2. As a result of disassembling the obtained battery and observing with a digital microscope, it was confirmed that a separator containing particles and a gelling agent on the support was prepared.

(Comparative Example 1) to (Comparative Example 16)
Lithium ion secondary batteries (4) to (19) were obtained in the same manner as in Example 1 except that the support and the electrolytic solution were changed as shown in Tables 2 and 3. As a result of disassembling and visually observing the obtained battery, it was confirmed that no particles were supported on the support in the lithium ion secondary battery (8). In the lithium ion secondary batteries (11) and (12), it was confirmed that particles and / or gelling agent were supported on the support. There were spots in the way. In the lithium ion secondary batteries (14) and (15), it was confirmed that particles and / or a gelling agent were supported on the support. In the lithium ion secondary batteries (17) to (19), since no support is used, disassembly observation is not performed.

  For the lithium ion secondary batteries (1) to (19) prepared in Examples 1 to 3 and Comparative Examples 1 to 16, the evaluation described in “(iv) Measurement of charge and discharge capacity of lithium ion secondary battery” was performed. . The results are shown in Tables 2 and 3.

  As can be seen from the results in Tables 2 and 3, a separator using the material having the specific pore structure of the present embodiment for the support and containing an electrolytic solution containing specific particles and / or a low molecular gelling agent. It was found that lithium ion secondary batteries (1) to (4) and (9) using lithium exhibited stable charging behavior. Further, the lithium ion secondary batteries (11) to (13) and (17) to (19) were short-circuited and could hardly be charged / discharged. Moreover, since the lithium ion secondary batteries (14) to (16) using the support body η that does not have the specific hole structure of the present embodiment have a small hole diameter of the support body, they may exhibit stable charge / discharge behavior. I understood.

(Examples 4 to 6)
The lithium ion secondary batteries (1) to (3) produced in Examples 1 to 3 were evaluated as described in “(v) Load characteristics of lithium ion secondary batteries”. Table 4 shows the value of the discharge capacity when the discharge current is 3 mA and the discharge capacity retention ratio at each discharge current value.

(Comparative Examples 17-21)
Regarding the lithium ion secondary batteries (4), (6), (9), (14), and (15) manufactured in Comparative Examples 1, 3, 6, 11, and 12, “(v) Load of the lithium ion secondary battery” Evaluation described in “Characteristics” was performed. Table 4 shows the value of the discharge capacity when the discharge current is 3 mA and the discharge capacity retention ratio at each discharge current value.

  As can be seen from the results in Table 4, a lithium ion secondary battery (1) using a material having a specific pore structure of the present embodiment for a support and a separator containing a specific low molecular gelling agent and particles is used. ) To (3) were found to be excellent in load characteristics. Moreover, it turned out that the lithium ion secondary batteries (14) and (15) using the support body (eta) which does not have the specific hole structure of this embodiment are inferior to a load characteristic, since the hole diameter of a support body is small.

(Example 7)
<Preparation of positive electrode>
Lithium nickel, manganese and cobalt mixed oxide having a number average particle diameter of 11 μm as a positive electrode active material, graphite carbon powder having a number average particle diameter of 6.5 μm and acetylene black powder having a number average particle diameter of 48 nm as a conductive auxiliary agent, and a binder And polyvinylidene fluoride (PVdF) were mixed at a mass ratio of 100: 4.2: 1.8: 4.6. N-methyl-2-pyrrolidone was added to the obtained mixture so as to have a solid content of 68% by mass and further mixed to prepare a slurry solution. This slurry-like solution was applied to one side of an aluminum foil having a thickness of 20 μm, and the solvent was dried and removed, followed by rolling with a roll press. The rolled product was punched into a rectangular shape with a length of 50 mm and a width of 30 mm to obtain a positive electrode (η).

<Production of negative electrode>
Graphite carbon powder having a number average particle diameter of 12.7 μm and graphite carbon powder having a number average particle diameter of 6.5 μm as a negative electrode active material, a carboxymethylcellulose solution (solid content concentration 1.83% by mass) as a binder, and a diene rubber ( Glass transition temperature: −5 ° C., number average particle size upon drying: 120 nm, dispersion medium: water, solid content concentration of 40% by mass) at a solid content mass ratio of 90: 10: 1.44: 1.76 A slurry-like solution was prepared by mixing so that the total solid concentration was 45% by mass. This slurry-like solution was applied to one side of a copper foil having a thickness of 18 μm, and the solvent was removed by drying, followed by rolling with a roll press. The rolled product was punched into a rectangular shape with a length of 52 mm and a width of 32 mm to obtain a negative electrode (θ).

<Battery assembly>
Two cup-shaped packaging materials with a laminated aluminum layer and resin layer (rectangular outer end dimension: 68 mm x 48 mm) are stacked so that the opening faces each other, and the three sides of the periphery are sealed to form a laminated cell exterior. Produced. Subsequently, a support (γ) is prepared, and a laminate obtained by alternately stacking the positive electrode (η) and the negative electrode (θ) produced as described above via the support (γ) is laminated. Arranged in the cell exterior. Next, gel electrolyte solution (e) obtained by adding aluminum oxide as particles and compound (a) synthesized as described above as gelling agent to mother electrolyte solution (A) in the cell exterior. (Particle content: 1 mass%, gelling agent content: 3 mass%) was added, and then the remaining side of the laminate cell exterior was sealed under reduced pressure to obtain a lithium ion secondary battery. The obtained lithium ion secondary battery was held at 95 ° C. under reduced pressure for 4 hours, and then cooled to 25 ° C. Then, this seal | sticker was performed under pressure reduction, and the single layer lamination type lithium ion secondary battery (20) which has a capacity | capacitance of 48 mAh was obtained.

(Comparative Example 22)
A laminated single-layer lithium ion secondary battery (21) was obtained in the same manner as in Example 7 except that the electrolytic solution (f) was used instead of the electrolytic solution (e).

(Comparative Example 23)
A laminated single-layer lithium ion secondary battery (22) was obtained in the same manner as in Example 7 except that the mother electrolyte (A) was used as it was instead of the electrolyte (e). In addition, injection | pouring of mother electrolyte (A) was performed, repeating atmospheric pressure and pressure reduction of 100 mmHg until a bubble generation | occurrence | production disappeared.

  The laminate type single layer lithium ion secondary batteries (20) to (22) obtained as described above are evaluated as described in "(vi) Evaluation of charging behavior of laminate type single layer lithium ion secondary battery". It was. The results are shown in Table 5.

  As can be seen from the results in Table 5, a lithium ion secondary battery using a separator having specific particles and / or a low-molecular gelling agent using the material having the specific pore structure of the present embodiment as a support (see FIG. 20) and (21) were found to be excellent in charge / discharge stability as compared with the lithium ion secondary battery (22) containing no particles or gelling agent. In addition, since some of the particles are filled in the large pore diameter peculiar to the support, it is understood that the lithium ion secondary battery (20) improves the nonuniformity of the charging current density and is more excellent in charging stability. It was.

(Example 8)
In the same manner as in Example 7, a laminate type laminated lithium ion secondary battery (23) having a capacity of 720 mAh was produced.

(Comparative Example 24)
A laminated laminated lithium ion secondary battery (24) was obtained in the same manner as in Example 8, except that the electrolytic solution (f) was used as it was instead of the electrolytic solution (e).

(Comparative Example 25)
A laminated laminated lithium ion secondary battery (25) was obtained in the same manner as in Example 8, except that the mother electrolyte (A) was used as the electrolyte instead of the electrolyte (e). In addition, injection | pouring of mother electrolyte (A) was performed, repeating atmospheric pressure and pressure reduction of 100 mmHg until a bubble generation | occurrence | production disappeared.
The laminate-type laminated lithium ion secondary batteries (23) to (25) prepared as described above were evaluated as described in "(vii) Evaluation of charging behavior of laminate-type laminated lithium ion secondary battery". The results are shown in Table 6.

  As can be seen from the results in Table 6, a lithium ion secondary battery using the support having the specific pore structure of the present embodiment and using an electrolytic solution containing specific particles and / or a low-molecular gelling agent. It was found that (23) and (24) were excellent in charge / discharge stability as compared with the lithium ion secondary battery (25) containing no particles and low molecular gelling agent. Further, it was found that the lithium ion secondary battery containing particles (23) improved the nonuniformity of the charging current density and was more excellent in charge / discharge stability.

Example 9
Using the lithium ion secondary battery (23) created in Example 8, the evaluation described in the above “(viii) Laminate type laminated lithium ion secondary battery overcharge test” was performed. The results are shown in Table 7.

(Comparative Examples 26-27)
Using the lithium ion secondary batteries (24) and (25) prepared in Comparative Examples 15 and 16, the evaluation described in the above “(viii) Laminate-type laminated lithium ion secondary battery” was performed. The results are shown in Table 7.

  As can be seen from the results in Table 7, a lithium ion secondary battery (23 using a support having a specific pore structure of this embodiment and using a separator containing specific particles and a low-molecular gelling agent (23) ) Did not cause a voltage drop even when the charging rate reached 230%. That is, it was found that the internal short-circuit suppressing effect by dendrite was seen and the battery became safer.

  The separator for non-aqueous batteries of the present invention can be used industrially as a separator for rechargeable batteries for automobiles such as hybrid cars, plug-in hybrid cars, and electric cars in addition to portable devices such as mobile phones, portable audios, and personal computers. Have sex.

  DESCRIPTION OF SYMBOLS 100 ... Lithium ion secondary battery, 110 ... Separator, 120 ... Positive electrode, 130 ... Negative electrode, 140 ... Positive electrode collector, 150 ... Negative electrode collector, 160 ... Battery exterior.

Claims (19)

A separator for a non-aqueous battery comprising a support containing particles and a low-molecular gelling agent,
The ratio of the number of holes having a minor axis of 1.0 μm or less out of the total number of holes of the support is 20% or less, and the total number of holes of the support is changed from one surface to the other surface. A separator for a nonaqueous battery in which the ratio of the number of continuous through-holes having a major axis of 150 μm or more is 10% or less.   The separator for nonaqueous batteries according to claim 1, wherein the particles include inorganic particles.   The separator for nonaqueous batteries according to claim 1 or 2, wherein the particles include a metal oxide.   The separator for nonaqueous batteries according to any one of claims 1 to 3, wherein the particles include at least one selected from the group consisting of aluminum oxide, boehmite, calcined kaolin, titanium oxide, zinc oxide, and magnesium oxide. .   The separator for nonaqueous batteries according to any one of claims 1 to 4, wherein an average primary particle diameter of the particles is 10 nm or more and 10 µm or less.   The separator for nonaqueous batteries according to claim 1, wherein the particles have a fractal structure.   The separator for nonaqueous batteries according to claim 1, wherein the support has an air permeability of 50 s / 100 cc or less.   The separator for nonaqueous batteries according to any one of claims 1 to 7, wherein a ratio of the number of holes having a minor axis of 200 µm or more in the total number of holes of the support is 5% or less.   The separator for nonaqueous batteries according to any one of claims 1 to 8, wherein a ratio of the number of holes having a minor axis of 1.0 µm or less among the holes present on the outermost surface of the support is 5% or less. .   The separator for nonaqueous batteries according to claim 1, wherein the support has a thickness of 20 μm or more and 60 μm or less.   The separator for nonaqueous batteries according to claim 1, wherein the support is a nonwoven fabric.   The separator for nonaqueous batteries according to any one of claims 1 to 11, which is obtained by impregnating the support with a nonaqueous solvent containing the low-molecular gelling agent and the particles. The separator for nonaqueous batteries according to any one of claims 1 to 12, wherein the low-molecular gelling agent contains one or more compounds selected from the group consisting of the following general formulas (1) and (2).
^{Rf 1 -R 1 -X 1 -L 1} -R 2 (1)
Rf ¹ -R ¹ -X ¹ -L ¹ -R ³ -L ² -X ² -R ⁴ -Rf ² (2)
(In the formulas (1) and (2),
Rf ¹ and Rf ² each independently represents a perfluoroalkyl group having 2 to 20 carbon atoms, and R ¹ and R ⁴ each independently represents a single bond or a divalent saturated hydrocarbon group having 1 to 6 carbon atoms. X ¹ and X ² each independently represent a divalent functional group selected from the group consisting of the following formulas (1a) to (1g), and L ¹ and L ² each independently represent a single bond or an alkyl group. Alternatively, an oxyalkylene group optionally substituted with a halogen atom, an alkyl group, an oxycycloalkylene group optionally substituted with a halogen atom, or a divalent oxyaromatic optionally substituted with an alkyl group or a halogen atom shows a family group, R ² is an alkyl group or a halogen atom (excluding a fluorine atom.) in the optionally substituted alkyl group having 1 to 20 carbon atoms, an alkyl group or A fluoroalkyl group, an aryl group or a fluoroaryl group which may be substituted with a rogen atom (excluding a fluorine atom), or one or more of these groups and a divalent group corresponding to these groups 1 represents a monovalent group bonded to one or more of the groups, R ³ may have one or more oxygen and / or sulfur atoms in the main chain, and is substituted with an alkyl group; And a C1-C18 divalent saturated hydrocarbon group. )
The separator for a non-aqueous battery according to claim 13, wherein X ¹ and X ² are each independently a divalent functional group represented by the formula (1a) or the formula (1d). The non-aqueous battery separator according to claim 13 or 14, wherein X ¹ and X ² are divalent functional groups represented by the formula (1d).   The separator for nonaqueous batteries according to any one of claims 1 to 15, wherein the low-molecular gelling agent and a part of the particles are present in pores of the support.   A positive electrode containing at least one material selected from the group consisting of a separator for a non-aqueous battery according to any one of claims 1 to 16 and a material capable of inserting and extracting lithium ions as a positive electrode active material. A negative electrode containing at least one material selected from the group consisting of a material capable of inserting and extracting lithium ions as a negative electrode active material and metallic lithium, a nonaqueous solvent, and a lithium salt. Water battery.   The nonaqueous battery according to claim 17, wherein the positive electrode includes a lithium-containing compound as the positive electrode active material.   The negative electrode contains, as the negative electrode active material, at least one material selected from the group consisting of metallic lithium, a carbon material, a material containing an element capable of forming an alloy with lithium, and a lithium-containing compound. The nonaqueous battery according to 17 or 18.