JP6971105B2 - Gel electrolytes, hard gel electrolytes, and electrochemical devices - Google Patents

Description

The present invention comprises a gel electrolyte containing a crosslinkable reactive group, which can be used as an electrolyte contained in an electrochemical device by subjecting the reactive group to a crosslink reaction and curing, and the gel electrolyte. The present invention relates to a cured hard gel electrolyte and an electrochemical device provided with the hard gel electrolyte.

As an electrochemical device using an electrochemical reaction, for example, various batteries, a part of a solar cell, a capacitor (capacitor) and the like are known. Conventionally, a liquid (electrolyte) has been used as the electrolyte used in these electrochemical devices. However, if the electrolyte is a general electrolyte, it cannot be denied that the electrolyte may leak from the electrochemical device. Therefore, in recent years, for example, a configuration using a gel electrolyte obtained by gelling an electrolytic solution has been proposed, as in the electrochemical cell disclosed in Patent Document 1 and the method for producing the same.

Japanese Patent Publication No. 2011-519116

Here, in the configuration in which the gel electrolyte is used as the electrolyte of the electrochemical device, a step of injecting an electrolytic solution (electrolyte injection liquid injection step) is required. Further, in order to gel the electrolytic solution, a prepolymer is generally used. The prepolymer is previously dissolved in an electrolytic solution, and such an electrolytic solution (prepolymer electrolytic solution) has a higher viscosity than a normal electrolytic solution.

Therefore, in the electrolytic solution injection step, it is necessary to inject a high-viscosity prepolymer electrolytic solution into the electrochemical device, which may prolong the time required for the electrolytic solution injection step. Therefore, the manufacturing process of the electrochemical device may not be sufficiently efficient.

Further, for example, when the electrochemical device is large, the amount of the prepolymer electrolytic solution to be injected becomes large in the electrolytic solution injection step. Therefore, there is a possibility that insufficient injection of the prepolymer electrolytic solution is likely to occur. If the prepolymer electrolyte is insufficiently injected, it may not be possible to achieve sufficient device performance in the electrochemical device.

The present invention has been made to solve such a problem, and it is possible to improve the efficiency of manufacturing an electrochemical device and to realize good device performance in the obtained electrochemical device. It is an object of the present invention to provide a gel electrolyte capable of providing a gel electrolyte.

In order to solve the above-mentioned problems, the gel electrolyte according to the present invention is a gel-like substance composed of at least a matrix material and an electrolytic solution, and contains a crosslinkable reactive group, and the reactive group is subjected to a crosslink reaction. The electrolytic solution is used as an electrolyte contained in an electrochemical device, and the electrolytic solution is composed of at least an ionic substance and an electrolytic solution solvent, and the mass of the reactive group contained in the gel-like body is the electrolytic solution. The composition is such that the range is 0.03% by mass or more and 6.5% by mass or less with respect to the mass of the solvent, and the shear elasticity of the gel-like substance in a state where the reactive group is unreacted is 1 MPa or more.

According to the above configuration, the uncured gel electrolyte contains an appropriate amount of reactive groups. Therefore, even if the gel electrolyte (hard gel electrolyte) in which the cross-linking reaction of the reactive group has sufficiently proceeded, the hard gel electrolyte can retain a sufficient amount of the electrolytic solution. Further, it becomes possible to leak a part of the electrolytic solution from the matrix material as the crosslinking reaction progresses. Therefore, if an electrochemical device is produced using a gel electrolyte in a state in which curing has not sufficiently progressed (uncured state) and then the cross-linking reaction is allowed to proceed, the contact surface of the electrode provided in the electrochemical device is provided. In addition, the leaked electrolyte can be brought into good contact. This makes it possible to realize a good electrochemical reaction in an electrochemical device.

Further, since the shear modulus of the gel electrolyte is 1 MPa or more even in the uncured state, the gel electrolyte has good strength. Therefore, it is possible to realize good handleability in the gel electrolyte, and it is possible to suppress inefficiency in the production of the electrochemical device. Moreover, as described above, since the electrochemical device may be produced using the gel electrolyte in an uncured state and then the crosslinking reaction may proceed, the liquid injection step is not required in the manufacturing process of the electrochemical device. Therefore, it is possible to avoid the risk of insufficient liquid injection or the risk of performance deterioration due to insufficient liquid injection.

As a result, it becomes possible to improve the efficiency of manufacturing the electrochemical device, and it is possible to realize good device performance in the obtained electrochemical device.

In the gel electrolyte having the above structure, the gel-like body may further contain the post-curing agent having the reactive group in addition to the matrix material and the electrolytic solution.

Further, in the gel electrolyte having the above structure, the mass of the electrolytic solution solvent may be in the range of 20% by mass or more and 80% by mass or less with respect to the total mass of the gel-like body.

Further, in the gel electrolyte having the above structure, the mass of the matrix material may be in the range of 1.0% by mass or more and 10% by mass or less with respect to the total mass of the gel-like body.

Further, in the gel electrolyte having the above constitution, the gel-like body contains a diluting solvent which is a component different from the electrolytic solution solvent and is removed before the cross-linking reaction of the reactive group, and is the same as the electrolytic solution solvent. The mass range or the mass range of the matrix material may be a configuration defined for the total mass of the gel-like body excluding the diluting solvent.

Further, in the gel electrolyte having the above-mentioned structure, the gel-like body may have a sheet-like structure.

Further, in the gel electrolyte having the above structure, the thickness of the gel-like body may be 5 μm or more and 100 μm or less.

The hard gel electrolyte according to the present disclosure has a structure in which the reactive groups in the gel electrolyte having the above constitution are crosslinked to increase the hardness thereof.

The hard gel electrolyte having the above-mentioned structure may have a structure that satisfies at least one of an ionic conductivity of 0.8 mS / cm or more and a shear modulus of 6 MPa or more.

Further, the electrochemical device according to the present disclosure may have a structure including the hard gel electrolyte having the above structure.

In the present invention, it is possible to provide a gel electrolyte capable of improving the efficiency of manufacturing an electrochemical device and achieving good device performance in the obtained electrochemical device by the above configuration. It has the effect of being able to do it.

It is a schematic cross-sectional view which shows the example of the structure of the lithium ion battery which is an example of the electrochemical device which concerns on embodiment of this disclosure.

The gel electrolyte according to the present disclosure is a gel-like body composed of at least a matrix material and an electrolytic solution, and contains a crosslinkable reactive group, and the reactive group is subjected to a crosslink reaction to be cured. , Used as an electrolyte in electrochemical devices. The electrolytic solution is composed of at least an ionic substance and an electrolytic solution solvent, but in the gel electrolyte according to the present disclosure, the mass of the reactive group contained in the gel electrolyte (gel-like body) is the mass of the electrolytic solution solvent. On the other hand, the gel electrolyte (gel-like substance) in the range of 0.03% by mass or more and 6.5% by mass or less and in the state where the reactive group is unreacted has a strength with a shear elasticity of 1 MPa or more. There is.

Hereinafter, a typical configuration example of the gel electrolyte according to the present disclosure will be specifically described. Since the gel electrolyte according to the present disclosure contains unreacted reactive groups as described above, the degree of curing of the gel electrolyte increases as the cross-linking reaction of the reactive groups proceeds. In the following description, the gel electrolyte whose degree of curing has increased due to the progress of the crosslinking reaction is referred to as "hard gel electrolyte". Further, when simply referred to as "gel electrolyte", it means a gel electrolyte before the degree of curing increases.

[Composition of gel electrolyte (gel-like body)]
As described above, the gel electrolyte according to the present disclosure is a gel-like body containing a matrix material and an electrolytic solution as main components, and the gel-like body contains unreacted reactive groups. The reactive group may be one possessed by the matrix material or the electrolytic solution, or both the matrix material and the electrolytic solution may have the reactive group, and the matrix material and the electrolysis may be present. A component other than the liquid may have a reactive group. As will be described later, the gel-like body (gel electrolyte) may contain components other than the matrix material and the electrolytic solution. Typical other components include post-curing agents having reactive groups.

The matrix material constituting the gel-like body is not particularly limited as long as it can form the gel-like body in a state containing the electrolytic solution. The matrix material may be a physical gel that forms a three-dimensional structure by a non-covalent bond such as a hydrogen bond, or a chemical gel that forms a three-dimensional structure by a covalent bond. In the present disclosure, since the gel-like body may have a reactive group capable of a cross-linking reaction, the matrix material may have an unreacted reactive group.

That is, in the present disclosure, for example, the matrix material is a compound that forms a physical gel (for convenience, it is referred to as a physical gel compound), and by adding an electrolytic solution to the matrix material, a gel-like body (is a gel-like body due to non-covalent bonding). A gel electrolyte) is formed, and the gel-like body has an unreacted reactive group. Alternatively, in the present disclosure, the matrix material is a compound that forms a chemical gel (referred to as a chemical gel compound for convenience), and a part of the reactive group of the matrix material is first crosslinked to be in a semi-cured state. A gel-like body (gel electrolyte) may be formed, and the semi-cured gel-like body may have a structure in which unreacted reactive groups remain.

At this time, the mass ratio of the reactive group contained in the gel (or remaining) may be in the range of 0.03% by mass or more and 6.5% by mass or less with respect to the mass of the electrolytic solution solvent as described above. (First condition of gel electrolyte described later). As described above, the reactive group may be contained in at least one of the matrix material and the electrolytic solution, or may be contained in the other component. Therefore, the mass ratio of the reactive group can be calculated by using the ratio of the molecular weight of the reactive group to the molecular weight of one molecule of the component having the reactive group (molecular weight ratio), as exemplified in Examples described later.

Here, it can be said that the gel electrolyte having an unreacted reactive group is in a state in which curing has not sufficiently progressed, and this state is referred to as an "uncured state" for convenience. Further, if the cross-linking reaction of the reactive group proceeds in the uncured gel electrolyte and the hardness increases to become a hard gel electrolyte, this state is referred to as a "cured state" for convenience. The above-mentioned "semi-cured state" means a state in which a part of all the reactive groups of the compound has reacted when the matrix material is a chemical gel compound.

Therefore, when most of all the reactive groups of the chemical gel compound are unreacted, the chemical gel compound does not form a gel. Further, the state in which some reactive groups of the chemical gel compound are crosslinked is the "semi-cured state", and the chemical gel compound is gelled. Since the reactive group remains in the range of 0.03 to 6.5% by mass with respect to the mass of the electrolytic solution solvent in this semi-cured chemical gel compound, the gel electrolyte (gel-like body) according to the present disclosure. ). Therefore, it can be said that a semi-cured chemical gel compound (that is, a gel electrolyte) is in an "uncured state". Then, if the cross-linking reaction of the reactive groups remaining in the semi-cured chemical gel compound proceeds and the hardness increases, the chemical gel compound becomes a cured hard gel electrolyte.

The specific configuration of the matrix material is not particularly limited. In general, the matrix material may be a polymer material. A suitable matrix material can be appropriately selected according to the use of the gel electrolyte according to the present disclosure, that is, the type of electrochemical device produced (manufactured) using the gel electrolyte according to the present disclosure. For example, in the examples described later, a lithium ion battery is exemplified as an example of an electrochemical device, but in this case, a polymer-based, inorganic-based, or low-molecular-weight system may be preferably used as the matrix material. can.

Examples of the polymer-based polymer include fluoride-based polymers such as polyvinylidene fluoride (PDVF) and vinylidene fluoride-hexafluoropropylene copolymer (PDVF-HFP); acrylic resins such as polyacrylonitrile (PAN) or methacrylic resins. ; Etc. can be mentioned, but are not particularly limited. Further, examples of the inorganic substance type include, but are not limited to, silica particles, alumina particles, silica / alumina mixed particles, titanium oxide particles, zinc oxide particles, zirconium oxide particles and the like. Examples of the low molecular weight system include, but are not limited to, fatty acid ester derivatives, cyclohexane derivatives, amino acid derivatives, cyclic peptide derivatives, alkyl hydrazide derivatives and the like.

Only one type of these matrix materials may be used, or two or more types may be appropriately selected and used in combination. For example, a plurality of types of polymer-based matrix materials may be used in combination, or one or more types of polymer-based and inorganic matrix materials may be used in combination. Alternatively, one or more polymer-based, inorganic-based, and low-molecular-weight systems may be selected and used in combination.

As described above, the gel-like body may contain a post-curing agent having a reactive group. After this, the curing agent can be regarded as a component different from the matrix material when the reactive group is unreacted, but if the cross-linking reaction by the reactive group proceeds sufficiently, it will form a part of the matrix material. Become. Therefore, the post-curing agent can be handled as a part of the matrix material, although it depends on the composition of the gel-like body and the like.

The specific composition of the post-curing agent is not particularly limited, and a suitable reactive compound can be selected depending on the composition of the gel electrolyte according to the present disclosure, the type of application (electrochemical device), and the like. For example, in the examples described later, a lithium ion battery is exemplified as an example of an electrochemical device, and the above-mentioned polymer-based or inorganic-based material is exemplified as a matrix material. In this case, the post-hardening agent is used. , Acrylate-based or oxetane-based reactive compounds can be mentioned.

Specific examples of the acrylate-based compound include, but are not limited to, tetrafunctional polyether acrylates, bifunctional polyether acrylates, other AO-added acrylates, polyethylene glycol diacrylates, and the like. Further, examples of the oxetane-based compound include, but are not limited to, a methyl methacrylate-oxetanyl methacrylate copolymer and the like. Only one kind of these post-curing agents may be used, or two or more kinds thereof may be used in combination as appropriate.

In addition, for example, when the matrix material is a chemical gel compound having an unreacted reactive group as described above, a gel-like body (gel electrolyte) in a semi-cured state by first cross-linking a part of the reactive groups. ) May be used with the same or different hardeners as the post-hardeners. In this case, the curing agent used first to realize the semi-curing state is referred to as a "pre-curing agent" in comparison with the post-curing agent.

The reactive groups contained in the gel electrolyte are crosslinked to increase the degree of curing of the gel electrolyte. The specific type of the reactive group is not particularly limited, and a suitable reactive group can be selected depending on the composition of the gel electrolyte, the type of application (electrochemical device), and the like. For example, in the examples described later, a lithium ion battery is exemplified as an example of an electrochemical device, and the above-mentioned polymer-based or inorganic-based material is exemplified as a matrix material. In this case, a reactive group as exemplified below can be preferably used.

Specific reaction groups include a (meth) acrylic group (acrylic group and methacrylic group), a double-bonding functional group such as an allyl group; an oxylan-based functional group such as an epoxy group and an oxetane group; a thiol group; an amino group. And a combination of functional groups of the condensation reaction system such as carboxy group (amide bond), hydroxy group and carboxy group (ester bond); isocyanate group such as isocyanate group and hydroxy group (urethane bond), isocyanate group and amino group (urea bond). Combinations of functional groups for system reactions; etc. Only one type of these functional groups (or a combination of functional groups) may be contained in the gel electrolyte (gel-like body), or two or more types may be contained. When the matrix material is a chemical gel compound having an unreacted reactive group, the compound may have at least one of these functional groups (or a combination thereof).

The electrolyte solution constituting the gel electrolyte may be any one capable of exhibiting an electrochemical reaction in an electrochemical device. The more specific composition of the electrolytic solution is not specifically limited as in the matrix material, but the composition of the gel electrolyte or the type of application (electrochemical device), the type of the matrix material constituting the gel electrolyte together with the electrolytic solution, etc. Therefore, an electrolytic solution having a suitable composition can be preferably used.

As described above, the electrolytic solution in the present disclosure may be a composition composed of at least an ionic substance and an electrolytic solution solvent. In the present embodiment, the electrolytic solution solvent means a solvent constituting the electrolytic solution of the electrochemical device. Further, various salts can be used as the ionic substance. For example, in the examples described later, a lithium ion battery is exemplified as an example of an electrochemical device. Therefore, in the present embodiment, a lithium salt can be mentioned as an ionic substance.

Typical examples of the lithium salt include lithium bis (trifluoromethanesulfonyl) imide (LiTFSI), lithium hexafluorophosphate (LiPF ₆ ), lithium bis (fluorosulfonyl) imide (LiFSI), and lithium perchlorate (LiClO _4). ), Lithium tetraborate (LiBF ₄ ) and the like, but are not particularly limited.

When the electrochemical device is a lithium ion battery, examples of the electrolytic solution solvent include carbonate-based solvents, ionic liquids, nitrile-based solvents, ether-based solvents, and the like, but are not particularly limited.

As a typical electrolytic solution solvent, a mixed solvent of a cyclic carbonate and a chain carbonate can be mentioned. Typical examples of the cyclic carbonate include ethylene carbonate (EC) and propylene carbonate (PC), and typical examples of the chain carbonate include dimethyl carbonate (DMC), diethyl carbonate (DEC), and ethylmethyl. Examples thereof include carbonate (EMC), but the present invention is not particularly limited.

Further, as another typical electrolytic solution solvent, an ionic liquid can be mentioned. Specifically, for example, 1,2-ethylmethylimidazolium bis (fluorosulfonyl) imide, 1,2-ethylmethylimidazolium bis (trifluoromethanesulfonyl) imide, 1-ethyl-3-methylimidazolium bis (fluoro). Sulfonyl) imide (abbreviation: EMImFSI), N-methylpropylpyrrolidinium bis (fluorosulfonyl) imide, N-methylpropylpyrrolidinium bis (trifluoromethanesulfonyl) imide, diethylmethylmethoxyethylammonium bis (trifluoromethanesulfonyl) imide , Siethylammonium bis (fluorosulfonyl) imide, diallyldimethylammonium (trifluoromethanesulfonyl) imide, diallyldimethylammonium (fluorosulfonyl) imide and the like, but are not particularly limited.

The gel electrolyte before the degree of curing increases may contain other components (other components) in addition to the matrix material and the electrolytic solution. Examples of other components include the above-mentioned post-curing agents, but other components include various additives. Specific examples of the additive include an initiator used to promote the cross-linking reaction of uncross-linked reactive groups contained in the matrix material. For example, in the examples described below, 2,2'-azobis (2,4-dimethylvaleronitrile) is used as the initiator.

[Structure of gel electrolyte and hard gel electrolyte]
In the gel electrolyte according to the present disclosure, the mass of the reactive group contained in the gel electrolyte (gel-like body) may be in the range of 0.03 to 6.5% by mass with respect to the mass of the electrolytic solution solvent. .. Further, in the gel electrolyte according to the present disclosure, the shear modulus thereof may be 1 MPa or more. That is, in the gel electrolyte according to the present disclosure, the "first condition" that the mass ratio of unreacted reactive groups is limited to a predetermined range and the lower limit of the shear elasticity in the unreacted state of the reactive groups are set to predetermined values. It satisfies both of the "second condition" of limitation.

As described above, the mass ratio of the reactive group to the electrolytic solution solvent, which is the first condition of the gel electrolyte, can be calculated by using the ratio of the molecular weight of the reactive group to the molecular weight of one molecule of the component having the reactive group (molecular weight ratio). good. For example, in the examples described later, in the gel electrolyte, the post-curing agent has a reactive group, but the ratio of the molecular weight of the reactive group to the molecular weight of the post-curing agent is calculated, and the post-curing is based on this molecular weight ratio. The mass of the reactive group is calculated from the compounding amount of the agent. The mass of this reactive group may be in the range of 0.03 to 6.5% by mass with respect to the mass of the electrolytic solution solvent contained in the gel electrolyte.

When the gel electrolyte satisfies the first condition, the uncured gel electrolyte contains an appropriate amount of unreacted reactive groups. Therefore, even if the cross-linking reaction of the reactive group proceeds to become a hard gel electrolyte, the hard gel electrolyte can retain a sufficient amount of the electrolytic solution. Further, it becomes possible to leak a part of the electrolytic solution from the matrix material as the crosslinking reaction progresses. Therefore, if an electrochemical device is prepared using an uncured gel electrolyte and then the cross-linking reaction is allowed to proceed, the leaked electrolyte can be satisfactorily brought into contact with the contact surface of the electrode of the electrochemical device. can. This makes it possible to realize a good electrochemical reaction in an electrochemical device.

The shear modulus of the uncured gel electrolyte, which is the second condition of the gel electrolyte, may be measured or evaluated by a known measuring method or evaluation method. In the examples described later, the uncured gel electrolyte obtained in each example or comparative example was subjected to a tabletop precision universal testing machine (product name: Autograph AGS-X) manufactured by Shimadzu Corporation, and had a diameter of 5 mm. After mounting the indentation jig and applying a 0.05N preload, the indentation test was carried out at a speed of 0.05 mm / min, and the shear modulus was measured from the result of the indentation test by the following formula (1). (Unit: MPa).

Shear modulus (G) = 0.36Fg [(D-h) / h] ^3/2 / R ² ... (1)
However, in the above formula (1), F is the load (test force) of the indentation test, g is the gravitational acceleration, D is the thickness (thickness) of the gel electrolyte (gel-like body), and h is the load. It is a change in thickness (thickness) due to, and R is the spherical radius of the spherical indenter in the indentation test. In addition, in the calculation of the shear modulus by the above equation (1), Reference 1: DJ Taylor and AM Kragh, “Determination of the rigidity modulus of thin soft coatings by indentation measurements” Journal of Physics D: Applied Physics, United Kingdom, IOP Publishing, January 1970, Volume 3, Number 1, 29 was referred to.

Since the gel electrolyte satisfies the second condition and the shear modulus of the gel electrolyte is 1 MPa or more even in the uncured state, the gel electrolyte has good strength. Therefore, it is possible to realize good handleability in the gel electrolyte, and it is possible to suppress inefficiency in the production of the electrochemical device. Further, as described above, since the electrochemical device may be produced using the gel electrolyte in an uncured state and then the crosslinking reaction may proceed, the liquid injection step becomes unnecessary in the manufacturing process of the electrochemical device. Therefore, it is possible to avoid the risk of insufficient liquid injection or the risk of performance deterioration due to insufficient liquid injection.

Here, the lower limit of the mass ratio of the reactive group, which is the first condition of the gel electrolyte, may be 0.03% by mass or more with respect to the mass of the electrolytic solution solvent, but may be 0.04% by mass or more. It is preferably 0.05% by mass or more, and more preferably 0.05% by mass or more. When the mass of the reactive group is less than 0.03% by mass of the mass of the electrolytic solution solvent, the amount of the reactive group contained in the gel electrolyte is smaller than the appropriate amount, and good strength can be realized in the hard gel electrolyte in the cured state. There is a risk that short circuits will occur more easily. In addition, the amount of leakage of the electrolytic solution with the progress of the crosslinking reaction is reduced, and the electrolytic solution cannot be satisfactorily contacted with the contact surface of the electrode of the electrochemical device, so that sufficient performance may not be realized in the electrochemical device.

The upper limit of the mass ratio of the reactive group may be 6.5% by mass or less with respect to the mass of the electrolytic solution solvent, preferably 6.3% by mass or less, and 6.0% by mass or less. It is more preferable to have. When the mass of the reactive group exceeds 6.5% by mass of the mass of the electrolytic solution solvent, the amount of the reactive group contained in the gel electrolyte becomes excessive, the ionic conductivity of the hard gel electrolyte is lowered, and it is sufficient for the electrochemical device. There is a risk that it will not be possible to achieve the desired performance. In addition, the amount of leakage of the electrolytic solution increases with the progress of the crosslinking reaction, and there is a possibility that a sufficient amount of the electrolytic solution cannot be retained in the cured state (hard gel electrolyte).

The lower limit of the shear modulus in the uncured state, which is the second condition of the gel electrolyte, may be 1 MPa or more, preferably 2 MPa or more, and more preferably 5 MPa or more. If the shear modulus is less than 1 MPa, the strength of the uncured gel electrolyte is lowered, so that the handleability is also lowered, and there is a possibility that the fabrication (manufacturing) of the electrochemical device becomes inefficient. The upper limit of the shear modulus is not particularly limited, and it is sufficient that a sufficient electrolytic solution can be retained in the cured hard gel electrolyte.

In the gel electrolyte according to the present disclosure, in addition to the first condition and the second condition described above, as a third condition, the mass of the electrolytic solution solvent is 20 mass with respect to the total mass of the gel electrolyte (gel-like body). The third condition, which is in the range of% or more and 80% by mass or less, and the mass of the matrix material are in the range of 1.0% by mass or more and 10% by mass or less with respect to the total mass of the gel electrolyte (gel-like body). It is preferable to satisfy either one of the fourth conditions, and it is more preferable to satisfy both the third condition and the fourth condition.

When the gel electrolyte satisfies the third condition, a more appropriate amount of the electrolytic solution is retained in both the gel electrolyte and the hard gel electrolyte. Therefore, good ionic conductivity can be realized in the electrochemical device, and the performance of the electrochemical device can be further improved. However, even when the gel electrolyte does not satisfy the third condition, a sufficiently practical electrochemical device can be produced by satisfying both the first condition and the second condition.

Further, when the gel electrolyte satisfies the fourth condition, both the gel electrolyte and the hard gel electrolyte contain a more appropriate amount of the matrix material. Therefore, good strength can be achieved in the hard gel electrolyte and the performance of the electrochemical device can be further improved. However, even when the gel electrolyte does not satisfy the fourth condition, a sufficiently practical electrochemical device can be produced by satisfying both the first condition and the second condition.

The specific shape of the gel electrolyte is not particularly limited, and a suitable shape can be formed according to various conditions such as the type or application of the electrochemical device. In particular, in the present disclosure, since the gel electrolyte is in the form of a gel, it can be easily formed into a desired shape. For example, in the examples described later, a lithium ion battery is exemplified as an example of an electrochemical device, so that a sheet shape can be mentioned as the shape of the gel electrolyte.

When the gel electrolyte has a sheet shape, its thickness (thickness of the gel electrolyte) is not particularly limited, but generally, a range of 5 μm or more and 100 μm or less can be mentioned. If the thickness of the sheet-like gel electrolyte falls outside this range, sufficient battery performance (or other electricity) will be sufficient, depending on conditions such as the type, dimensions, and specific shape of the lithium-ion battery (or other electrochemical device). Performance of chemical devices) may not be exhibited.

The hard gel electrolyte is one in which the cross-linking reaction of the reactive groups of the gel electrolyte is promoted to increase the hardness, but the specific composition of the hard gel electrolyte is not particularly limited. However, in the hard gel electrolyte, it is preferable to satisfy either the first condition that the ionic conductivity is 0.8 mS / cm or more or the second condition that the shear modulus is 6 MPa or more. It is more preferable to satisfy both the first condition and the second condition.

If the ionic conductivity of the hard gel electrolyte is 0.8 mS / cm or more, preferably 1.0 mS or more, a good electrochemical reaction can be realized, so that sufficient performance can be exhibited in an electrochemical device. can. On the other hand, if the ionic conductivity is less than 0.8 mS / cm, good electrochemical reaction may not be realized depending on the type of electrochemical device, so sufficient performance may not be exhibited. There is.

Further, when the shear modulus of the hard gel electrolyte is 6 MPa or more, the electrolyte layer in the electrochemical device can be held well, so that sufficient performance can be exhibited. On the other hand, if the shear modulus of the hard gel electrolyte is less than 6 MPa, it may not be possible to hold the electrolyte layer well, depending on the type of electrochemical device, so sufficient performance may not be exhibited. be.

As described above, if the cross-linking reaction of the reactive group is allowed to proceed in the uncured gel electrolyte to increase the hardness, the cured gel electrolyte becomes a cured hard gel electrolyte. As a guideline for this cured state, the hard gel is obtained. The shear elasticity of the electrolyte is 6 MPa. Of course, the hardness of the gel electrolyte may be measured by a known measuring method, and the cured state may be determined based on the numerical value of the hardness or the rate of increase in hardness, etc., but in the present disclosure, the uncured gel electrolyte and Since the strength of the hard gel electrolyte is evaluated by the shear elastic modulus, it can be determined that the hard gel electrolyte has become a hard gel electrolyte if the shear elastic modulus of the gel electrolyte with increased hardness is 6 MPa or more.

[Manufacturing method of gel electrolyte]
The method for producing the gel electrolyte according to the present disclosure is not particularly limited, but as a typical production method, a first method using two kinds of diluting solvents, a second method using one kind of diluting solvent, and a diluting solvent are used. A third method that does not use the above can be mentioned. This diluting solvent is a component different from the electrolytic solution solvent, and is a component from which the reactive groups contained in the gel-like body (gel electrolyte) are removed before the cross-linking reaction. Therefore, the gel electrolyte according to the present disclosure may contain a diluting solvent as a component other than the matrix material and the electrolytic solution.

The third and fourth conditions of the above-mentioned uncured gel electrolyte, that is, the mass range of the electrolytic solution solvent in the gel electrolyte and the mass range of the matrix material in the gel electrolyte are the total mass of the gel electrolyte excluding the diluting solvent. Is stipulated for. This is because, as described above, the diluting solvent is removed before the cross-linking reaction of the reactive groups, in other words, the cured hard gel electrolyte contains substantially no diluting solvent. Is.

The specific type of the diluting solvent is not particularly limited, and can be appropriately selected depending on various conditions such as the type of electrochemical device, the type of matrix material, and the components of the electrolytic solution. For example, in the examples described later, a lithium ion battery is exemplified as an example of an electrochemical device, so that the solvent exemplified below can be preferably used as the diluting solvent.

Specifically, examples of the diluting solvent that can be contained in the gel electrolyte include ketone solvents such as acetone, methyl ethyl ketone (MEK), and cyclohexanone; ether solvents such as 1,2-dimethoxyethane (DME); acetonitrile (ACN). ) And other nitrile solvents; N-methylpyrrolidone (NMP) and other pyrrolidone solvents; γ-butyrolactone (GBL) and other lactone solvents; ethylene carbonate (EC), propylene carbonate (PC), dimethyl carbonate (DMC), Carbonated solvents such as diethyl carbonate (DEC) and ethylmethyl carbonate (EMC); and the like can be mentioned. As these solvents, one type may be used as the diluting solvent in the present disclosure, or two or more types may be appropriately selected and used. When two or more kinds of these solvents are used, each solvent may be used for different dilution purposes, or may be used as a mixed solvent in which two or more kinds of solvents are mixed.

Among the typical methods for producing a gel electrolyte according to the present disclosure, the first method using two kinds of diluting solvents will be described.

In the first method, first, the matrix material and the first diluting solvent are mixed to form a gel-like body (non-electrolyte gel-like body) containing no electrolytic solution (non-electrolyte gel-like body forming step). The method of mixing the matrix material and the first diluting solvent is not particularly limited, but a typical method is to dissolve the matrix material in the first diluting solvent by heating the matrix material and the first diluting solvent. Be done. After dissolution, a non-electrolyte gel can be obtained by cooling to room temperature, for example. The first diluting solvent can be referred to as a gel diluting solvent used for forming a non-electrolyte gel.

Next, in the first method, an electrolyte component (ionic substance such as a lithium salt), an electrolytic solution solvent and other components (post-curing agent, initiator, etc.) are dissolved in a second diluting solvent, and the electrolytic solution or the like is prepared. Prepare a diluted solution. For convenience of explanation, this diluted solution is referred to as a substitution solution (substitution solution preparation step). The method for preparing the substitution solution is not particularly limited, and a known mixer or the like may be used. Then, this substitution solution is added to the non-electrolyte gel (substitution solution addition step). The method of adding the substitution solution is not particularly limited, and examples thereof include application or accumulation of the substitution solution on a non-electrolyte gel. Since the added substitution solution is absorbed by the non-electrolyte gel, a gel containing a diluting solvent is obtained.

In the first method, the diluting solvent is then removed from the gel containing the diluting solvent (diluting solvent removing step). The method for removing the diluting solvent is not particularly limited, but for example, the diluting solvent may be evaporated and distilled off under reduced pressure conditions or high temperature conditions. In this step, both the gel diluting solvent and the replacement diluting solvent are removed, but focusing on the non-electrolyte gel-like body formed first, the gel-diluting solvent contained in the non-electrolyte gel-like body is electrolytic. It will be replaced with a liquid. The gel electrolyte according to the present disclosure may be a gel-like body containing a diluting solvent, or may be a gel-like body from which the diluting solvent has been removed. That is, the diluting solvent may be removed immediately before the electrochemical device is manufactured (manufactured), or the diluting solvent may be removed in advance.

Next, among the typical methods for producing a gel electrolyte according to the present disclosure, a second method using one kind of diluting solvent will be described.

In the second method, a diluted solution of the matrix material is prepared by mixing the matrix material and the diluting solvent in the same manner as in the first method. For convenience of explanation, the diluted solution of this matrix material is referred to as "Liquid A" (Liquid A preparation step). Next, the electrolyte component (ionic substance such as lithium salt), the electrolyte solution solvent and other components (post-curing agent, initiator, etc.) are dissolved in the same type of diluting solvent as the solution A, and the diluted solution such as the electrolytic solution is dissolved. To prepare. For convenience of explanation, this diluted solution such as an electrolytic solution is referred to as "solution B" (solution B preparation step).

Next, in the second method, the prepared liquids A and B are mixed, and the obtained mixed liquid is molded into a predetermined shape (mixed molding step). The method for molding the mixed solution is not particularly limited, and a molding mold, a support, or the like depending on the shape of the gel electrolyte to be obtained may be used. For example, in the examples described later, a lithium ion battery is exemplified as an example of an electrochemical device. Therefore, the positive electrode of the lithium ion battery is used as a support, and the mixed solution is coated on the surface of the positive electrode. As a result, a gel-like body containing a diluting solvent is formed. Then, as in the first method, the diluting solvent is removed from the gel containing the diluting solvent (diluting solvent removing step).

Next, among the typical methods for producing a gel electrolyte according to the present disclosure, a third method that does not use a diluting solvent will be described. In the third method, an electrolytic solution solvent is used instead of using a diluting solvent that dissolves the matrix material or the electrolyte.

In the third method, a matrix material and an electrolytic solution solvent are mixed to prepare an electrolytic solution solvent solution of the matrix material. For convenience of explanation, the solution of this matrix material is referred to as "Liquid A" as in the second method (Liquid A preparation step). Next, the electrolyte component (ionic substance such as lithium salt) and other components (post-curing agent, initiator, etc.) are dissolved in the same or different type of electrolyte solvent as the solution A, and the electrolyte solvent such as the electrolyte solution is dissolved. Prepare the solution. For convenience of explanation, this solution such as an electrolytic solution is referred to as "solution B" as in the second method (solution B preparation step). Then, the prepared liquids A and B are mixed, and the obtained mixed liquid is molded into a predetermined shape (mixed molding step). As a result, a gel-like body containing an electrolytic solution or the like, that is, a gel electrolyte can be obtained.

Since each of the first method, the second method, and the third method has unique manufacturing advantages, it cannot be concluded that either method is particularly preferable. For example, in the first method, as described above, a replacement solution is prepared using a diluting solvent, and the liquid component of the non-electrolyte gel is replaced with the electrolytic solution using this replacement solution. Therefore, by appropriately changing the composition of the substitution solution, various variations of the obtained gel electrolyte can be easily produced.

Further, in the second method, when manufacturing a lithium ion battery, the positive electrode or the negative electrode can be used as a support, and the mixed solution can be applied to the positive electrode or the negative electrode. Therefore, since it is possible to avoid an increase in the manufacturing process of the lithium ion battery as compared with the first method, it is possible to simplify the manufacturing method of the lithium ion battery. Further, in the third method, the electrolytic solution solvent is used without using the diluting solvent. As a result, the gel electrolyte can be obtained only by molding the mixed solution into a predetermined shape, so that the step of removing the diluting solvent becomes unnecessary as compared with the first method or the second method. Therefore, the manufacturing method of the electrochemical device can be simplified.

[Electrochemical device]
Next, a representative example of the electrochemical device according to the present disclosure manufactured by using the gel electrolyte having the above constitution will be specifically described. The electrochemical device according to the present disclosure is not particularly limited as long as it utilizes an electrochemical reaction (a device capable of converting chemical energy and electrical energy), but a typical configuration is a pair of electrodes. , An electrolyte located between them, and a configuration comprising.

The specific configuration of the pair of electrodes included in the electrochemical device is not particularly limited, but typically, the pair of electrodes is configured as a positive electrode and a negative electrode, respectively. The specific configurations of the positive electrode and the negative electrode are not particularly limited, but in order to increase the contact area with the electrolytic solution contained in the electrolyte, for example, the contact surface (the surface facing the electrolyte) is porous. Is preferable. Such a porous contact surface may be possessed only by the positive electrode, may be possessed only by the negative electrode, or may be possessed by both the positive electrode and the negative electrode. The specific configuration of the pair of electrodes (positive electrode, negative electrode) is not particularly limited, and various materials, shapes, dimensions, etc. may be preferably used according to the type or application of the electrochemical device. can.

The method for forming the porous contact surface is not particularly limited, but a typical method is to form a powder (or particles) of the electrode material (active material) in a layer on the surface of the electrode base material. As a method of forming such a powder material into layers, the powder of the electrode material (active material) is mixed with an organic vehicle (solvent and / or binder resin, etc.) to form a paste, which is applied to the surface of the electrode base material. Then, a method of drying, curing, baking, or the like can be mentioned.

The electrolyte contained in the electrochemical device is interposed between the pair of electrodes, and in the present disclosure, this electrolyte is in a cured state in which the degree of curing of the uncured gel electrolyte is increased, as described above. Any hard gel electrolyte may be used.

Further, the typical configuration of the electrochemical device according to the present disclosure is a configuration including a pair of electrodes and a hard gel electrolyte as described above, but the configuration of the electrochemical device in the present disclosure is not limited to this. , A pair of electrodes and components or members other than the gel electrolyte or hard gel electrolyte. The specific configuration of such other components or other members is not particularly limited, and various components or components depending on the specific type of the electrochemical device can be used.

More specific configurations of the electrochemical device according to the present disclosure include, for example, a lithium ion battery, a dye-sensitized solar cell, an electric double layer capacitor, a gel actuator and the like. A specific configuration of a lithium ion battery, which is a typical example of the electrochemical device in the present disclosure, will be specifically described with reference to FIG.

As shown in FIG. 1, the lithium ion battery 10, which is a kind of electrochemical device, has a positive electrode 12 and a negative electrode 13 as a pair of electrodes, and a hard gel electrolyte 14 is held between the positive electrode 12 and the negative electrode 13. have. The structure in which the positive electrode 12, the hard gel electrolyte 14 and the negative electrode 13 are laminated (the structure in which the hard gel electrolyte 14 is held in the positive electrode 12 and the negative electrode 13) is referred to as a laminated structure 11 for convenience. The lithium ion battery 10 has a structure in which the laminated structure 11 is sealed with a sealing material 15.

As shown in FIG. 1, the positive electrode 12 has a configuration in which the positive electrode active material layer 22 is formed on the surface of the positive electrode base material 21 (the surface facing the negative electrode 13 and in contact with the hard gel electrolyte 14). ing. Similarly, the negative electrode 13 has a structure in which the negative electrode active material layer 32 is formed on the surface of the negative electrode base material 31 (the surface facing the positive electrode 12 and in contact with the hard gel electrolyte 14).

The positive electrode base material 21 and the negative electrode base material 31 function as a current collector that collects electrons generated by the electrochemical reaction of the positive electrode active material layer 22 and the negative electrode active material layer 32. The specific configurations of the positive electrode base material 21 and the negative electrode base material 31 are not particularly limited, and a known metal plate or metal foil may be used. In the examples described later, an aluminum foil is used as the positive electrode base material 21. Further, a copper foil is typically used as the negative electrode base material 31.

The positive electrode active material used for the positive electrode active material layer 22 is typically a lithium salt of a transition metal oxide, but is not particularly limited. In the examples described later, Li-Ni-Co-Mn oxide (NCM), which is a ternary lithium salt, is used as the positive electrode active material. As the negative electrode active material used for the negative electrode active material layer 32, a lithium metal foil or a carbon material is typically used. In the examples described later, a lithium metal foil is used as the negative electrode active material. Further, the positive electrode active material layer 22 may be composed of only the positive electrode active material, the negative electrode active material layer 32 may be composed of only the negative electrode active material, or may be configured as a layer containing other components. ..

For example, when the positive electrode active material layer 22 and the negative electrode active material layer 32 are formed by coating with a coating liquid containing an active material, a known binder resin such as polyvinylidene fluoride (PVDF), carbon black or the like, etc. The known conductive auxiliary agent of the above may be contained. Further, the coating liquid may contain a solvent (dispersion medium) in addition to the active material, the binder resin, and the conductive auxiliary agent. Further, from the viewpoint of improving the contact frequency with the positive electrode active material layer 22 or the negative electrode active material layer 32, the coating liquid has a degree of curing similar to that of the gel electrolyte before increasing the degree of curing or the hard gel electrolyte 14. It may contain a gel electrolyte (hard gel electrolyte component) having an increased amount of water.

The positive electrode active material layer 22 constitutes a facing surface facing the negative electrode 13 in the positive electrode 12, and also constitutes a contact surface with respect to the hard gel electrolyte 14. Similarly, the negative electrode active material layer 32 constitutes a facing surface facing the positive electrode 12 in the negative electrode 13 and a contact surface with respect to the hard gel electrolyte 14. Therefore, as described above, it is preferable that at least one of the positive electrode active material layer 22 and the negative electrode active material layer 32 is formed in a porous form.

The method for forming the active material layers 22 and 32 in a porous form is not particularly limited, and various known methods can be used. Typically, as described above, a method of applying a paste containing an active material and drying it can be mentioned. Further, either one of the active material layers 22 and 32 does not have to be porous. In the examples described later, the positive electrode active material layer 22 is formed in a porous form, but the negative electrode active material layer 32 is formed only of the lithium foil.

Since the lithium foil also serves as a current collector (negative electrode base material 31) together with the negative electrode active material, the negative electrode 13 is composed of only the lithium foil in the examples described later. Therefore, at least the positive electrode 12 and the negative electrode 13 need not be composed of the active material layers 22 and 32 and the base materials 21 and 31 supporting them, as illustrated in FIG.

As described above, the hard gel electrolyte 14 is formed by reacting the reactive groups contained in the uncured gel electrolyte and advancing the crosslinking reaction to increase the degree of curing of the gel electrolyte.

The sealing material 15 is not particularly limited as long as it can seal the laminated structure 11 composed of the positive electrode 12, the negative electrode 13, and the hard gel electrolyte 14. As the sealing material 15, if the electrochemical device is a lithium ion battery 10, a known laminated film, a known metal can, or the like can be typically used. The laminated film is typically a metal foil such as an aluminum foil or a stainless steel foil laminated with a resin film such as polypropylene (PP), but is not particularly limited. If the electrochemical device is a dye-sensitized solar cell, examples of the encapsulant 15 include known sealing agents such as a thermoplastic ionomer resin.

The lithium ion battery 10 shown in FIG. 1 does not have a separator. This is because the hard gel electrolyte 14 held by the positive electrode 12 and the negative electrode 13 can function in the same manner as the separator. Further, the lithium ion battery 10 may be provided with a separate separator, or may be provided with a member other than the positive electrode 12, the negative electrode 13, and the hard gel electrolyte 14.

As described above, according to the present disclosure, the uncured gel electrolyte contains an appropriate amount of reactive groups. Therefore, even if the gel electrolyte (hard gel electrolyte) in which the cross-linking reaction of the reactive group has sufficiently proceeded, the hard gel electrolyte can retain a sufficient amount of the electrolytic solution. Further, it becomes possible to leak a part of the electrolytic solution from the matrix material as the crosslinking reaction progresses. Therefore, if an electrochemical device is produced using a gel electrolyte in a state in which curing has not sufficiently progressed (uncured state) and then the cross-linking reaction is allowed to proceed, the contact surface of the electrode provided in the electrochemical device is provided. In addition, the leaked electrolyte can be brought into good contact. This makes it possible to realize a good electrochemical reaction in an electrochemical device.

Further, since the shear modulus of the gel electrolyte is 1 MPa or more even in the uncured state, the gel electrolyte has good strength. Therefore, it is possible to realize good handleability in the gel electrolyte, and it is possible to suppress inefficiency in the production of the electrochemical device. Moreover, as described above, since the electrochemical device may be produced using the gel electrolyte in an uncured state and then the crosslinking reaction may proceed, the liquid injection step is not required in the manufacturing process of the electrochemical device. Therefore, it is possible to avoid the risk of insufficient liquid injection or the risk of performance deterioration due to insufficient liquid injection.

As a result, according to the present disclosure, it is possible to improve the efficiency of manufacturing the electrochemical device and to realize good device performance in the obtained electrochemical device.

The present disclosure will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto. One of ordinary skill in the art can make various changes, modifications, and modifications without departing from the scope of the present invention. The measurements and evaluations of various synthetic reactions and physical properties in the following examples were carried out as shown below.

(Measurement of shear modulus of gel electrolyte)
For the shear modulus of the gel electrolyte obtained in each example or each comparative example, a desktop precision universal testing machine (product name: Autograph AGS-X) manufactured by Shimadzu Corporation was used, and a 5 mmφ indentation jig was attached. Then, after applying a 0.05 N preload, a indentation test was carried out at a speed of 0.05 mm / min, and based on the results of the indentation test, shear modulus was applied according to the following equation (1) with reference to Reference 1 above. The rate was measured (unit: MPa).

Shear modulus (G) = 0.36Fg [(D-h) / h] ^3/2 / R ² ... (1)
(F: load (test force) of indentation test, g: gravitational acceleration, D: thickness (thickness) of gel electrolyte (gel-like body), h: change in thickness (thickness) due to load, R: indentation test Sphere radius of the spherical indenter)
(Measurement of ionic conductivity of gel electrolyte)
The thickness (film thickness) of the gel electrolyte obtained in each Example or Comparative Example was measured. Further, the gel electrolyte sandwiched between stainless steel foils was allowed to stand in a constant temperature bath at 80 ° C. for 12 hours to allow the cross-linking reaction to proceed and return to room temperature, and the gel electrolyte was used as a hard gel electrolyte. Using this as a sample for ionic conductivity measurement, this sample was electrochemically used under the condition of a frequency of 1 MHz to 0.1 Hz using an impedance analyzer (product name: SP-150) manufactured by Bio-Logic SAS. The bulk resistance value of the gel electrolyte was obtained by measuring the impedance (EIS). The ionic conductivity at 30 ° C. was calculated by dividing the film thickness of the gel electrolyte by the bulk resistance value (unit: mS / cm).

(Battery performance evaluation of electrochemical devices)
The evaluation coin cell (electrochemical device according to the present disclosure) obtained in each Example or each Comparative Example was subjected to a charge / discharge test device (manufactured by Toyo System Co., Ltd., product name: TOSCAT3100) under 25 ° C. conditions. Then, while charging is executed at a 0.1C time rate, discharging is executed under the condition of 0.1C to 1C time rate, and the capacity retention rate (Q1C / Q0.1C) of the 1C discharge capacity with respect to the 0.1C discharge capacity is evaluated.

If the capacity coercivity is 90% or more, it is evaluated as "○" (good), if the capacity coercivity is 70% or more, it is evaluated as "△" (normal), and if the capacity coercivity is less than 70%. It was evaluated as "x" (inappropriate).

(Evaluation of device stability of electrochemical devices)
In each Example or each Comparative Example, a total of 10 evaluation coin cells (electrochemical devices according to the present disclosure) were produced, and these evaluation coin cells were used with a charge / discharge test device (product name: TOSCAT3100) manufactured by Toyo System Co., Ltd. The device stability test was carried out by executing charging at a 1C time rate under the condition of 25 ° C. and discharging 100 times under the condition of 1C time rate. Of the 10 evaluation coin cells produced, if the occurrence of short circuit is 1 or less, it is evaluated as "○" (good), and if the occurrence of short circuit is less than 5, it is evaluated as "△" (normal). If the number of short circuits was 5 or more, it was evaluated as "x" (inappropriate).

(Example 1)
The following work was carried out in a dry air atmosphere with a dew point of −50 ° C. or lower. As shown in Table 1, 1.8 parts by mass of polyvinylidene fluoride (PVDF, manufactured by Kureha Co., Ltd., product name: KF Polymer # 7200), which is a matrix material, is added to acetone (Wako Pure Chemical Industries, Ltd.), which is a diluting solvent for gels. Manufactured) PVDF / acetone gel (non-electrolyte gel) was prepared by heating and dissolving in 33 parts by mass at 80 ° C. and allowing to stand at room temperature.

Further, as shown in Table 1, 10 parts by mass of lithium bis (fluorosulfonyl) imide (LiFSI, manufactured by Kishida Chemical Co., Ltd., lithium battery grade (LBG)), which is a lithium salt, is an ionic liquid-based electrolytic solution solvent. 49 parts by mass of 1-ethyl-3-methylimidazolium bis (fluorosulfonyl) imide (EMImFSI, manufactured by Daiichi Kogyo Seiyaku Co., Ltd., product name: Elexel IL-110), a tetrafunctional polyether acrylate as a post-curing agent ( Made by Daiichi Kogyo Seiyaku Co., Ltd., product name: Elexel TA-210) in 1.3 parts by mass, 2,2'-azobis (2,4-dimethylvaleronitrile) (Wako Junyaku Co., Ltd.), which is an azo-based initiator. A substitution solution was prepared by blending 0.49 parts by mass of company-made product name; V-65) and 3.8 parts by mass of acetonitrile (ACN) which is a diluting solvent for substitution.

This substitution solution is added onto a PVDF / acetone gel, and acetone (diluting solvent for gel) and acetonitrile (diluting solvent for substitution) are distilled off under normal temperature and vacuum conditions to prepare a gel electrolyte according to Example 1. (Manufactured).

Here, in the gel electrolyte according to Example 1, the crosslinkable reactive group is an acrylate group contained in a tetrafunctional polyether acrylate (product name: Elexel TA-210) which is a post-curing agent. Since the weight average molecular weight of the tetrafunctional polyether acrylate used is 11000 and the molecular weight of the four acrylate groups contained in one molecule is 220, the mass of the acrylate group contained in 1 g of the tetrafunctional polyether acrylate is 0. It is 0.02 g.

As described above, in Example 1, the blending amount of the tetrafunctional polyether acrylate as the post-curing agent is 1.3 parts by mass. Therefore, the mass of the reactive group (acrylate group) contained in the gel electrolyte according to Example 1 is 0.025 parts by mass. Further, as described above, in Example 1, the blending amount of EMImFSI, which is an electrolytic solution solvent, is 49 parts by mass. Therefore, as shown in Table 1, in the gel electrolyte according to Example 1, the mass ratio of the reactive group to the mass of the electrolytic solution solvent is 0.050% by mass, which is in the range of 0.03 to 6.5% by mass. It's inside.

Further, as shown in Table 1, in the gel electrolyte according to Example 1, the mass ratio of the electrolytic solution solvent to the total mass is 78% by mass, which is within the range of 20 to 80% by mass, and the total mass. The mass ratio of the matrix material to the mass ratio is 2.9% by mass, which is in the range of 1.0 to 10% by mass.

_{100 g of LiNi 1/3} Mn _1/3 Co _1/3 O ₂ which is a positive electrode active material, 7.8 g of acetylene black (manufactured by Denka Co., Ltd., product name: Denka Black HS-100) as a conductive auxiliary agent, binder resin Weighed 3.3 g of polyvinylidene fluoride (PVDF, manufactured by Kureha Co., Ltd., weight average molecular weight Mw: about 300,000) and 38.4 g of N-methyl-2-pyrrolidone (NMP) as a dispersion medium. The mixture was mixed with a mixer to prepare a coating liquid for a positive electrode active material layer having a solid content of 51%. Cathode The coating liquid was coated on an aluminum foil with a thickness of 15 [mu] m (Seikyokumotozai) in coating apparatus, followed by conducting roll press treatment after drying at 130 ° C., having a positive electrode active material layer of 2.3 mg / cm ² Got

This positive electrode, the gel electrolyte according to Example 1, and the lithium foil as the negative electrode were superposed to form a laminated body. A sealed body was produced by punching this laminated body into a circular shape having a diameter of 14 mm and sealing it in a coin cell jig. By allowing this sealant to stand in a constant temperature bath at 80 ° C. for 12 hours, the cross-linking reaction of the reactive groups contained in the gel electrolyte was sufficiently allowed to proceed (the gel electrolyte was cured to obtain a hard gel electrolyte). , Returned to room temperature. In this way, an evaluation coin cell (lithium ion battery), which is the electrochemical device according to the first embodiment, was manufactured (manufactured).

As described above, the obtained gel electrolyte according to Example 1 is measured or evaluated for shear modulus, film thickness, and ionic conductivity, and the obtained evaluation coin cell has battery performance and element stability (short circuit). Was evaluated. The results are shown in Table 1.

(Examples 2 and 3)
The gel electrolyte according to Example 2 or the gel electrolyte according to Example 3 in the same manner as in Example 1 except that the amount of the electrolyte solvent and the amount of the post-curing agent were changed as shown in Table 1. Was produced, and an evaluation coin cell, which is an electrochemical device according to Example 2 or an electrochemical device according to Example 3, was produced.

As shown in Table 1, in both the gel electrolyte according to Example 2 and the gel electrolyte according to Example 3, the mass ratio of the reactive group to the mass of the electrolytic solution solvent is 0.03 to 6.5 mass. The mass ratio of the electrolytic solution solvent to the total mass is in the range of 20 to 80% by mass, and the mass ratio of the matrix material to the total mass is in the range of 1.0 to 10% by mass. It's inside.

With respect to the obtained gel electrolyte according to Example 2 or 3, the shear modulus, film thickness, and ionic conductivity were measured or evaluated as described above, and the battery performance and element stability of the obtained evaluation coin cell ( (Short circuit) was evaluated. The results are shown in Table 1.

(Example 4)
The following work was carried out in a dry air atmosphere with a dew point of −50 ° C. or lower, as in Examples 1 to 3. As shown in Table 2, a matrix material, a vinylidene fluoride-hexafluoropropylene copolymer (PVDF-HFP, manufactured by Kureha Corporation, product name: KF Polymer # 8500, Table 2 shows “PVDF-HFP [1]” for convenience. 2.9 parts by mass was heated and dissolved at 80 ° C. with 29.5 parts by mass of dimethyl ether (DME, manufactured by Wako Pure Chemical Industries, Ltd.) as a diluting solvent. As a result, solution A, which is a DME diluted solution of PVDF-HFP, was prepared.

Further, as shown in Table 2, 9.3 parts by mass of LiFSI (see Example 1), which is a lithium salt, and 28 parts by mass of EMImFSI (see Example 1), which is an ionic liquid-based electrolyte solvent, are post-cured. 0.90 parts by mass of the tetrafunctional polyether acrylate (see Example 1) as an agent, 0.12 parts by mass of an azo-based initiator (see Example 1) as an initiator, and 29 parts of DME as a diluting solvent. .5 parts by mass was mixed and mixed to prepare a solution B which is a solution for diluting DME such as an electrolytic solution.

The gel according to Example 4 was obtained by mixing the obtained liquids A and B, applying this mixed solution to the surface of the positive electrode described above, and distilling off the DME (diluting solvent) under normal temperature and vacuum conditions. A laminate of electrolyte and positive electrode was prepared (manufactured).

As shown in Table 2, in the gel electrolyte according to Example 4, a tetrafunctional polyether acrylate is blended as the post-curing agent as in Examples 1 to 3, and the same as in Example 1. The mass ratio of the reactive groups is derived. As shown in Table 2, the mass ratio of the reactive group to the mass of the electrolytic solution solvent is in the range of 0.03 to 6.5% by mass (0.063% by mass). Further, as shown in Table 2, in the gel electrolyte according to Example 4, the mass ratio of the electrolytic solution solvent to the total mass is in the range of 20 to 80% by mass (68% by mass) with respect to the total mass. The mass ratio of the matrix material is in the range of 1.0 to 10% by mass (7.0% by mass).

Further, this gel electrolyte / positive electrode laminate is punched into a circular shape having a diameter of 14 mm, and a lithium foil having a diameter of 14 mm, which is a negative electrode, is bonded to the gel electrolyte side of the obtained punched body to form a bipolar cell (tom cell). I set it. In this way, an evaluation coin cell (lithium ion battery), which is the electrochemical device according to Example 4, was manufactured (manufactured).

Regarding the obtained gel electrolyte (gel electrolyte / positive electrode laminate) according to Example 4, the shear elasticity, film thickness, and ionic conductivity were measured or evaluated as described above, and the obtained coin cell for evaluation was used. Battery performance and element stability (short circuit) were evaluated. The results are shown in Table 2.

(Examples 5 to 13)
Whether the compounding amount of the electrolyte solvent and the compounding amount of the post-curing agent are changed as shown in Table 2 (Examples 5 and 6), or the bifunctional polyether acrylate (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., product) as the post-curing agent. Name: MP-150) is used to appropriately change the blending amount of the electrolyte solvent as shown in Table 2 or 3 (Examples 7 to 9), or polyethylene glycol diacrylate (Daichi Kogyo Seiyaku Co., Ltd.) as a post-hardening agent. The compounding amount of the electrolytic solution solvent is changed as shown in Table 3 using a product name: Elexel EG2500 manufactured by the company (Example 10), or a methyl methacrylate-oxetanyl methacrylate copolymer (No. 1) as a post-hardening agent. The same as in Example 4 except that the blending amount of the electrolytic solution solvent is changed as shown in Table 3 using (Product Name: Elexel ACG-127) manufactured by Ichiko Pharmaceutical Co., Ltd. The gel electrolyte according to Examples 5 to 13 was prepared. In addition, using these gel electrolytes, evaluation coin cells, which are the electrochemical devices according to Examples 5 to 13, were produced.

Here, in the gel electrolyte according to Examples 7 to 9, the crosslinkable reactive group is the acrylate group contained in the post-curing agent, the bifunctional polyether acrylate (product name: MP-150). Since the weight average molecular weight of the bifunctional polyether acrylate used is 11000 and the molecular weight of the two acrylate groups contained in one molecule is 110, the mass of the acrylate group contained in 1 g of the bifunctional polyether acrylate is 0. It is 010 g.

For example, in Example 7, as shown in Table 2, the blending amount of the bifunctional polyether acrylate as the post-curing agent is 1.4 parts by mass. Therefore, the mass of the reactive group (acrylate group) contained in the gel electrolyte according to Example 7 is 0.0138 parts by mass. Further, in Example 7, as shown in Table 2, the blending amount of EMImFSI, which is an electrolytic solution solvent, is 28 parts by mass. Therefore, as shown in Table 2, in the gel electrolyte according to Example 7, the mass ratio of the reactive group to the mass of the electrolytic solution solvent is 0.050% by mass, which is in the range of 0.03 to 6.5% by mass. It's inside.

Similarly, as shown in Table 2 or Table 3, the gel electrolyte according to Example 8 or Example 9 also contains the same bifunctional polyether acrylate as in Example 7 as a post-curing agent, and Example 7 Similarly, the mass ratio of the reactive group is derived. As shown in Table 2, in these Examples 8 and 9, the mass ratio of the reactive group to the mass of the electrolyte solvent was 0.44% by mass (Example 8) or 2.5% by mass (Example 9). All of them are in the range of 0.03 to 6.5% by mass.

Further, in the gel electrolyte according to Example 10, the crosslinkable reactive group is an acrylate group contained in polyethylene glycol diacrylate (product name: Elexel EG2500) which is a post-curing agent. Since the polyethylene glycol diacrylate used has a weight average molecular weight of 2500 and the molecular weight of the acrylate group contained in one molecule is 83, the mass of the acrylate group contained in 1 g of the polyethylene glycol diacrylate is 0.033 g.

In Example 10, as shown in Table 3, the blending amount of the polyethylene glycol diacrylate as the post-curing agent is 6.7 parts by mass. Therefore, the mass of the reactive group (acrylate group) contained in the gel electrolyte according to Example 10 is 0.221 parts by mass. Further, in Example 10, as shown in Table 3, the blending amount of EMImFSI, which is an electrolytic solution solvent, is 28 parts by mass. Therefore, in the gel electrolyte according to Example 10, the mass ratio of the reactive group to the mass of the electrolytic solution solvent is 1.0% by mass, which is in the range of 0.03 to 6.5% by mass.

Further, in the gel electrolyte according to Examples 11 to 13, the crosslinkable reactive group is the oxetane moiety contained in the methylmethacrylate-oxetanylmethacrylate copolymer (product name: Elexel ACG-127) which is a post-curing agent. .. Since the methyl methacrylate-oxetanyl methacrylate copolymer used has a weight average molecular weight of 300,000 and the molecular weight of one oxetane portion is 56, the mass of the oxetane portion contained in 1 g of the methyl methacrylate-oxetanyl methacrylate copolymer. Is 0.13 g.

For example, in Example 11, as shown in Table 3, the blending amount of the post-curing agent, methyl methacrylate-oxetanyl methacrylate copolymer, is 0.12 parts by mass. Therefore, the mass of the reactive group (oxetane portion) contained in the gel electrolyte according to Example 11 is 0.015 parts by mass. Further, in Example 11, as shown in Table 3, the blending amount of EMImFSI, which is an electrolytic solution solvent, is 29 parts by mass. Therefore, as shown in Table 2, in the gel electrolyte according to Example 11, the mass ratio of the reactive group to the mass of the electrolytic solution solvent is 0.050% by mass, which is in the range of 0.03 to 6.5% by mass. It's inside.

Similarly, as shown in Table 3, the gel electrolyte according to Example 12 or Example 13 also contains the same methyl methacrylate-oxetanyl methacrylate copolymer as in Example 11 as a post-curing agent, and Example 11 Similarly, the mass ratio of the reactive group is derived. As shown in Table 3, in these Examples 11 and 12, the mass ratio of the reactive group to the mass of the electrolytic solution solvent was 1.2% by mass (Example 12) or 5.6% by mass (Example). 13), and all of them are in the range of 0.03 to 6.5% by mass.

As shown in Table 2, in the gel electrolytes according to Examples 5 and 6, a tetrafunctional polyether acrylate was blended as the post-curing agent in the same manner as in Examples 1 to 4, and the same as in Example 1 Similarly, the mass ratio of the reactive groups is derived. As shown in Table 2, also in Examples 5 and 6, the mass ratio of the reactive group to the mass of the electrolytic solution solvent is in the range of 0.03 to 6.5% by mass (see Example 1). ).

Further, as shown in Table 2 or Table 3, in each of the gel electrolytes according to Examples 5 to 13, the mass ratio of the electrolytic solution solvent to the total mass is in the range of 20 to 80% by mass. The mass ratio of the matrix material to the total mass is in the range of 1.0 to 10% by mass.

As described above, the shear modulus, film thickness, and ionic conductivity of each of the obtained gel electrolytes according to Examples 5 to 13 were measured or evaluated, and the battery performance and element stability of each of the obtained evaluation coin cells were obtained. The sex (short circuit) was evaluated. The results are shown in Table 2 or Table 3.

(Examples 14 to 16)
As shown in Table 4, as the matrix material, PVDF-HFP of a type different from that of Examples 4 to 13 (manufactured by Kureha Co., Ltd., product name: KF Polymer # 9300, Table 4 shows "PVDF-HFP [2]" for convenience. (Example 14), or silica particles (manufactured by Nippon Aerosil Co., Ltd., product name: Aerosil 200, described as "silica" in Table 4), which are inorganic particles, are used as the matrix material (Example 15). ) Or, as a matrix material, silica / alumina mixed particles (manufactured by Nippon Aerosil Co., Ltd., product name: Aerosil COK84, referred to as "silica / alumina" in Table 4) are used for electrolysis (Example 16). The gel electrolytes according to Examples 14 to 16 were prepared in the same manner as in Example 4 except that the blending amounts of the liquid solvent and the post-curing agent were changed. In addition, using these gel electrolytes, evaluation coin cells, which are the electrochemical devices according to Examples 14 to 16, were produced.

As shown in Table 4, in each of the gel electrolytes according to Examples 14 to 16, the mass ratio of the reactive group to the mass of the electrolytic solution solvent was in the range of 0.03 to 6.5% by mass. The mass ratio of the electrolytic solution solvent to the total mass is in the range of 20 to 80% by mass, and the mass ratio of the matrix material to the total mass is in the range of 1.0 to 10% by mass.

As described above, the shear modulus, film thickness, and ionic conductivity of each of the obtained gel electrolytes according to Examples 14 to 16 were measured or evaluated, and the battery performance and element stability of each of the obtained evaluation coin cells were obtained. The sex (short circuit) was evaluated. The results are shown in Table 4.

(Example 17)
The following work was carried out in a dry air atmosphere with a dew point of −50 ° C. or lower, as in Examples 1 to 16. As shown in Table 5, 1.0 part by mass of PVDF-HFP [2] (manufactured by Kureha Co., Ltd., product name: KF Polymer # 9300) as the matrix material as in Example 14 is a carbonate-based electrolyte solvent. To 39.5 parts by mass of a mixture (mixed electrolyte solvent) of 55 parts by mass of dimethyl carbonate (DMC, manufactured by Kishida Chemical Co., Ltd., LBG) and 5.3 parts by mass of ethylene carbonate (EC, manufactured by Kishida Chemical Co., Ltd., LBG). The mixture was heated and dissolved at 80 ° C. As a result, solution A, which is a DMC diluted solution of PVDF-HFP, was prepared.

Further, as shown in Table 5, _{14 parts by mass of lithium hexafluorophosphate (LiPF 6} , manufactured by Kishida Chemical Co., Ltd., LBG), which is a lithium salt, and 39.5 parts of the above-mentioned mixed electrolyte solvent of DMC and EC. Mix by mass, 0.90 parts by mass of tetrafunctional polyether acrylate (see Example 1) as a post-curing agent, and 0.30 parts by mass of an azo-based initiator (see Example 1) as an initiator. Then, solution B was prepared. As shown in Table 5, no diluting solvent was used in this example.

The obtained liquids A and B were mixed, and the mixed solution was applied to the surface of the positive electrode described above to prepare (manufacture) a laminate of the gel electrolyte and the positive electrode according to Example 17.

As shown in Table 5, in the gel electrolyte according to Example 17, the mass ratio of the reactive group to the mass of the electrolytic solution solvent was in the range of 0.03 to 6.5% by mass (0.013). Mass ratio), the mass ratio of the electrolytic solution solvent to the total mass is in the range of 20 to 80 mass% (79 mass%), and the mass ratio of the matrix material to the total mass is in the range of 1.0 to 10 mass%. It is inside (1.0% by mass).

Further, this gel electrolyte / positive electrode laminate is punched into a circular shape having a diameter of 14 mm, and a lithium foil having a diameter of 14 mm, which is a negative electrode, is bonded to the gel electrolyte side of the obtained punched body to form a bipolar cell (tom cell). I set it. In this way, an evaluation coin cell (lithium ion battery), which is the electrochemical device according to Example 17, was manufactured (manufactured).

Regarding the obtained gel electrolyte (gel electrolyte / positive electrode laminate) according to Example 17, the shear elasticity, film thickness, and ionic conductivity were measured or evaluated as described above, and the obtained evaluation coin cell was used. Battery performance and element stability (short circuit) were evaluated. The results are shown in Table 5.

(Examples 18 to 20)
As shown in Table 5, ethylmethyl carbonate (EMC, manufactured by Kishida Chemical Co., Ltd., LBG, Example 18) and diethyl carbonate (DEC, manufactured by Kishida Chemical Co., Ltd.) are used as the carbonate electrolyte solvent for preparing the solution A. When changing to LBG, Example 19) or propylene carbonate (PC, manufactured by Kishida Chemical Co., Ltd., LBG, Example 20) and using PC, the blending amounts of PC and EC were changed (Example 20). ), The gel electrolyte according to Examples 18 to 20 was prepared in the same manner as in Example 17. In addition, using these gel electrolytes, evaluation coin cells, which are the electrochemical devices according to Examples 18 to 20, were produced.

As shown in Table 5, in each of the gel electrolytes according to Examples 18 to 20, the mass ratio of the reactive group to the mass of the electrolytic solution solvent was in the range of 0.03 to 6.5% by mass. The mass ratio of the electrolytic solution solvent to the total mass is in the range of 20 to 80% by mass, and the mass ratio of the matrix material to the total mass is in the range of 1.0 to 10% by mass.

As described above, the shear modulus, film thickness, and ionic conductivity of each of the obtained gel electrolytes according to Examples 18 to 20 were measured or evaluated, and the battery performance and element stability of each of the obtained evaluation coin cells were obtained. The sex (short circuit) was evaluated. The results are shown in Table 5.

(Examples 21 to 26)
As shown in Table 6, although the mass ratio of the reactive group to the electrolytic solution solvent in the gel electrolyte is in the range of 0.03 to 6.5 mass%, the mass ratio of the electrolytic solution solvent to the total mass in the gel electrolyte is 20. The matrix material may be less than mass% (Example 21), more than 80% by mass (Example 22), ionic conductivity less than 0.8 mS / cm (Example 23), or the matrix material with respect to the total mass of the gel electrolyte. The mass ratio may be less than 1.0% by mass (Example 24), may exceed 10% by mass (Example 25), the film thickness of the gel electrolyte may be 100 μm or more, and the blending amount of each component may be changed. Except for the above, the same as in Example 4 (Examples 21 and 23 to 26) or the same as in Example 17 (Example 22, however, only one type of EC is used as the electrolyte solvent), and Examples 21 to 26 are used. The gel electrolyte according to the above was prepared. In addition, using these gel electrolytes, evaluation coin cells, which are the electrochemical devices according to Examples 21 to 26, were produced.

As described above, the shear modulus, film thickness, and ionic conductivity of each of the obtained gel electrolytes according to Examples 21 to 26 were measured or evaluated, and the battery performance and element stability of each of the obtained evaluation coin cells were obtained. The sex (short circuit) was evaluated. The results are shown in Table 6.

(Comparative Examples 1 and 2)
As shown in Table 7, the mass ratio of the reactive group to the electrolyte solvent in the gel electrolyte may be less than 0.03% by mass (Comparative Example 1) or more than 6.5% by mass (Comparative Example 2). The gel electrolyte according to Comparative Example 1 or the gel electrolyte according to Comparative Example 2 is produced in the same manner as in Example 4 described above except that the blending amount of the components is changed, and the electrochemical device or the electrochemical device according to Comparative Example 1 is produced. An evaluation coin cell, which is an electrochemical device according to Comparative Example 2, was produced.

As described above, the shear modulus, film thickness, and ionic conductivity of the obtained gel electrolyte according to Comparative Example 1 or 2 are measured or evaluated, and the battery performance and element stability of the obtained evaluation coin cell ( (Short circuit) was evaluated. The results are shown in Table 7.

(Comparison between Examples and Comparative Examples)
As is clear from the comparison between Examples 1 to 26 and Comparative Examples 1 and 2, in the gel electrolyte according to the present disclosure, an electrochemical device having good performance by satisfying the first condition and the second condition ( (Lithium-ion battery) can be manufactured. On the other hand, it can be seen that the performance of the electrochemical device cannot be sufficiently obtained, especially when the first condition is not satisfied.

Further, as is clear from the comparison between Examples 4 to 13 and Examples 17 to 20 and Examples 21 to 26, in the gel electrolyte according to the present disclosure, in addition to the first condition and the second condition, a third condition is added. By satisfying at least one of the condition and the fourth condition, an electrochemical device (lithium ion battery) having even better performance can be manufactured.

Further, as is clear from the comparison of Examples 1 to 3, Examples 4 to 16, and Examples 17 to 20, in the gel electrolyte according to the present disclosure, the first method, the second method, or the third method. A gel electrolyte produced by any of the above methods can be used to produce an electrochemical device (lithium ion battery) having good performance.

It should be noted that the present invention is not limited to the description of the above-described embodiment, and various modifications can be made within the scope of the claims, and the present invention is disclosed in different embodiments and a plurality of modifications. Embodiments obtained by appropriately combining the above technical means are also included in the technical scope of the present invention.

INDUSTRIAL APPLICABILITY The present invention can be widely and suitably used in the field of electrochemical devices using a gel electrolyte, such as lithium ion batteries, dye-sensitized solar cells, electric double layer capacitors, and gel actuators.

10: Lithium ion battery 11: Laminated structure 12: Positive electrode 13: Negative electrode 14: Hard gel electrolyte 15: Encapsulant 21: Positive electrode base material 22: Positive electrode active material layer 31: Negative electrode base material 32: Negative electrode active material layer

Claims (10)

It is a gel-like body composed of at least a matrix material and an electrolytic solution, and contains a crosslinkable reactive group.
By cross-linking the reactive group and curing it, it is used as an electrolyte in an electrochemical device.
The matrix material is at least one of a fluoride polymer or an inorganic particle, and is
The reactive group is at least one of an acrylic group which is a double-binding functional group, a methacrylic group or an allyl group, or an epoxy group or an oxetane group which is an oxylan-based functional group.
The electrolytic solution is composed of at least an ionic substance (excluding those containing iodine) and an electrolytic solution solvent.
The mass of the reactive group contained in the gel-like body is in the range of 0.03% by mass or more and 6.5% by mass or less with respect to the mass of the electrolytic solution solvent.
The mass of the electrolytic solution solvent is in the range of 20% by mass or more and 80% by mass or less with respect to the total mass of the gel-like body.
The mass of the matrix material is in the range of 1.0% by mass or more and 10% by mass or less with respect to the total mass of the gel-like body.
The gel-like body has a shear modulus of 1 MPa or more when the reactive group is unreacted.
Gel electrolyte. The gel-like body is characterized by further containing the post-curing agent having the reactive group in addition to the matrix material and the electrolytic solution.
The gel electrolyte according to claim 1. The post-curing agent is characterized by being an acrylate-based reactive compound or an oxetane-based reactive compound.
The gel electrolyte according to claim 2. The fluoride- based polymer is polyvinylidene fluoride (PDVF) or vinylidene fluoride-hexafluoropropylene copolymer (PDVF-HFP).
The inorganic particles are characterized by being silica particles, alumina particles, silica / alumina mixed particles, titanium oxide particles, zinc oxide particles, and zirconium oxide particles.
The gel electrolyte according to any one of claims 1 to 3. The gel-like substance contains a diluting solvent which is a component different from the electrolyte solvent and is removed before the cross-linking reaction of the reactive group.
The mass range of the electrolytic solution solvent or the mass range of the matrix material is defined with respect to the total mass of the gel-like body excluding the diluting solvent.
The gel electrolyte according to claim 3 or 4. The gel-like body is characterized by having a sheet shape.
The gel electrolyte according to any one of claims 1 to 5. The gel-like body is characterized in that the thickness is 5 μm or more and 100 μm or less.
The gel electrolyte according to claim 6. It is characterized in that the reactive group in the gel electrolyte according to any one of claims 1 to 7 is crosslinked to increase its hardness.
Hard gel electrolyte. It is characterized by satisfying at least one of an ionic conductivity of 0.8 mS / cm or more and a shear modulus of 6 MPa or more.
The hard gel electrolyte according to claim 8. The hard gel electrolyte according to claim 8 or 9 is provided.
Electrochemical device.

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