Electrolyte and battery including electrolyte

Abstract

An electrolyte comprising a porous insulator having pores, and a metal salt and a medium disposed in the pores, wherein the metal salt is at least one kind selected from the group consisting of alkali metal salts and alkaline earth metal salts, and the molar ratio (medium / metal salt) of the medium to the metal salt is 0.1-2.0.

Description

Electrolyte and battery containing the electrolyte

[0001] The present disclosure relates to electrolytes and batteries comprising the electrolytes.

[0002] Batteries include air batteries, fuel cells, secondary batteries, etc., and are used for a variety of purposes. Batteries include a positive electrode and a negative electrode, and an electrolyte that transports ions between the positive electrode and the negative electrode.

[0003] For example, Patent Document 1 discloses an insulating structure made of a porous coordination polymer having metal salt coordinated unsaturated sites, and a [R-SO ２ -N-SO ２ -R'] － (R and R' represent a fluorine atom or a fluoroalkyl group) and a metal cation (e.g., Li ＋ , Na ＋ , or Mg ２＋ ) and an ion-conductive composite (electrolyte) comprising the same.

[0004] Furthermore, Patent Document 2 discloses an electrolyte regulator that can be used in metal batteries, the electrolyte regulator comprising a liquid electrolyte and a metal-organic framework (MOF) material that is incorporated into the liquid electrolyte to form an MOF slurry electrolyte, where MOFs are a class of crystalline porous solids constructed from metal cluster nodes and organic linkers, and are capable of binding anions, removing ion pairs, and enhancing cation transport upon activation and impregnation with the liquid electrolyte.

[0005] Patent No. 6222635 Special Publication No. 2020-508542

[0006] The present inventors have realized that there are still problems to be overcome with the above electrolytes and have found the need to take measures to solve these problems. Specifically, the present inventors have found that there is room for improvement in the ionic conductivity of the electrolytes.

[0007] The present disclosure has been made in view of the above-mentioned problems. That is, a main object of the present disclosure is to provide an electrolyte having superior ionic conductivity compared to conventional electrolytes.

[0008] The present inventors attempted to solve the above problems by taking a new approach rather than simply extending the conventional technology, and as a result, they have invented an electrolyte that achieves the above-mentioned main object.

[0009] An electrolyte according to one embodiment of the present disclosure comprises a porous insulator having pores, and a medium and a metal salt disposed in the pores, wherein the metal salt is at least one selected from the group consisting of alkali metal salts and alkaline earth metal salts, and the molar ratio of the medium to the metal salt (medium / metal salt) is 0.1 or more and 2.0 or less.

[0010] Moreover, a battery according to an embodiment of the present disclosure includes the above-described electrolyte.

[0011] The present disclosure can provide an electrolyte with superior ionic conductivity.

[0012] 1 is a conceptual diagram showing an example of a battery according to a second embodiment of the present disclosure. －１ 3 shows the Raman spectra of the electrolytes of Examples 1 to 8 and Comparative Examples 1 and 2 in the range of 680 to 780 cm －１ 4 is a graph showing the relationship between the molar ratio (SL / LiFSI) and the ionic conductivity at room temperature. FIG. 5 is a graph showing the relationship between the molar ratio (EC / LiFSI) and the ionic conductivity at room temperature. FIG. 6 is a graph showing the relationship between the molar ratio (EC / LiFSI) and the ionic conductivity at room temperature. －１ 7 shows the Raman spectra in the range of 680 to 800 cm of the electrolytes of Examples 23, 25 to 26 and Comparative Example 1. －１ This is the Raman spectrum at

[0013] The "electrolyte" and the "battery" including the electrolyte of the present disclosure will be described in detail below with reference to the following embodiments. While the description will be made with reference to the drawings as needed, the contents shown in the drawings are merely shown as a schematic example for the purpose of understanding the present disclosure, and the appearance and dimensional ratios may differ from the actual products.

[0014] Numerical ranges mentioned in this specification are intended to include the lower and upper limit values ​​themselves, unless otherwise specified, for example, by using terms such as "less than," "smaller," or "greater than." In other words, a numerical range such as 1 to 10 is interpreted as including the lower limit of 1 and the upper limit of 10.

[0015] In this specification, the expression "a target component is substantially composed of a specific material" or "a target component is made of a specific material" means that the target component contains the specific material at a ratio of 95% by mass or more, 97% by mass or more, 99% by mass or more, or 100% by mass. For example, when mesoporous silica is silica (SiO ２ The term "essentially composed of mesoporous silica" means that the mesoporous silica is composed of silica (SiO ) in a proportion of 95% by mass or more, 97% by mass or more, 99% by mass or more, or 100% by mass. ２ ) is included.

[0016] In the present disclosure, the term "battery" broadly refers to a device equivalent to 1 or 2 that can extract energy using an electrochemical reaction. In a narrower sense, the term "battery" refers to a device that includes a pair of electrodes and an electrolyte, and that is charged and discharged particularly through the movement of ions. By way of example only, examples of batteries include primary batteries and secondary batteries, and more specifically, lithium batteries, magnesium batteries, sodium batteries, and potassium batteries.

[0017] In this disclosure, unless otherwise specified, the term "electrolyte solution" refers to the electrolyte according to the present disclosure excluding the porous insulator, and is composed of a metal salt and a medium.

[0018] First Embodiment: Electrolyte The electrolyte according to the first embodiment of the present disclosure is used in, for example, a battery. That is, the electrolyte described in this specification corresponds to an electrolyte for a device that can extract energy by utilizing an electrochemical reaction.

[0019] The electrolyte according to the first embodiment is, as a premise, an electrolyte used in a battery having an electrode composed of lithium, magnesium, sodium, or potassium. In particular, it is an electrolyte for a battery having a lithium electrode as the negative electrode. Therefore, the electrolyte according to the first embodiment can also be said to be an electrolyte for a lithium electrode-based battery (hereinafter, also simply referred to as a "lithium electrode-based electrolyte").

[0020] Here, the term "lithium electrode" as used herein broadly refers to an electrode having lithium (Li) as the active component (i.e., active material). In a narrower sense, "lithium electrode" refers to an electrode comprising lithium, for example, an electrode comprising lithium metal or a lithium alloy, particularly a negative electrode of such lithium. While such a lithium electrode may contain components other than lithium metal or a lithium alloy, in a preferred embodiment it is an electrode made of a lithium metal body (for example, an electrode made of lithium metal with a purity of 90% or more, preferably 95% or more, and more preferably 98% or more).

[0021] The electrolyte according to the first embodiment has Li ion conductivity in the case of a lithium electrode system. The ionic conductivity of the electrolyte according to the first embodiment is, for example, 10 －４ The ionic conductivity is a value on the order of S / cm or more. The method for measuring the ionic conductivity will be described in detail in the Examples.

[0022] The electrolyte according to the first embodiment includes a porous insulator having pores, and a medium (medium molecules) and a metal salt disposed in the pores, wherein the metal salt is at least one selected from the group consisting of alkali metal salts and alkaline earth metal salts, and the molar ratio of the medium to the metal salt (medium / metal salt) is 0.1 or more and 2.0 or less.

[0023] (Molar ratio (medium / metal salt)) The molar ratio of the medium to the metal salt (medium / metal salt) is 0.1 or more and 2.0 or less. If the molar ratio is less than 0.1 or more than 2.0, the ionic conductivity decreases. From the viewpoint of further improving the ionic conductivity of the electrolyte, the lower limit of the molar ratio is preferably 0.2, more preferably 0.3, and the upper limit of the molar ratio is preferably 1.9, more preferably 1.5, even more preferably 1.2, particularly preferably 1.0, and very preferably 0.8. By arbitrarily selecting and combining from the above multiple suitable numerical ranges, a suitable numerical range of the molar ratio (a numerical range including the upper and lower limits) can be achieved. For example, the molar ratio is preferably 0.2 or more and 2.0 or less.

[0024] In particular, the molar ratio (sulfolane / LiFSi) is preferably 0.1 to 1.5, more preferably 0.2 to 1.2, even more preferably 0.2 to 1.0, and particularly preferably 0.3 to 0.5. The molar ratio (ethylene carbonate / LiFSi) is preferably 0.2 to 2.0, more preferably 0.3 to 1.0.

[0025] -Method for determining the molar ratio (medium / metal salt)- The molar ratio (medium / metal salt) can be determined from the amounts of the medium and metal salt (molar ratio in the raw material state) that constitute the electrolyte according to this embodiment. Alternatively, the molar ratio (medium / metal salt) can be determined from the electrolyte (as a finished product).

[0026] [Mechanism of Action] The electrolyte according to this embodiment has superior ionic conductivity. Without being bound by any particular theory, the reason for this is presumed to be as follows. In the electrolyte according to this embodiment, a bridge structure can be formed by combining a metal salt and a medium at a specific molar ratio (medium / metal salt = 0.1 to 2.0). Specifically, the electrolyte according to this embodiment can have at least one of a bridge structure (hereinafter also referred to as a "first bridge structure") in which the medium and positive ions (more specifically, metal ions) constituting the metal salt are arranged alternately, and a bridge structure (hereinafter also referred to as a "second bridge structure") in which positive ions constituting the metal salt and negative ions constituting the metal salt are arranged alternately.

[0027] When the first bridge structure and the second bridge structure are disposed in the pores of the porous insulator, defects (holes) in which metal ions are missing can be formed, which can serve as paths for efficient transport of metal ions within the electrolyte. Therefore, in the electrolyte according to this embodiment, the formation of the bridge structures in the pores of the porous insulator increases the ionic conductivity of metal ions.

[0028] (Motivation behind the Invention of the Present Disclosure) When a porous insulator is impregnated with an electrolyte solution used in lithium-ion batteries, the ionic conductivity is still low. The present inventors have intensively studied concepts for improving this ionic conductivity. As a result, they have found that by forming bridge structures within the pores and allowing metal ions to propagate through at least one of the first bridge structure and the second bridge structure within the pores, the ionic conductivity is higher than when metal ions propagate within the pores in a solvated state. This led the present inventors to conceive of an electrolyte according to this embodiment, which improves ionic conductivity through a completely new mechanism that is not found in conventional concepts, namely, carrier transport through at least one of the first bridge structure and the second bridge structure.

[0029] (First Bridge Structure) The electrolyte according to this embodiment preferably has a first bridge structure from the viewpoint of further improving ion conductivity. In the first bridge structure, the medium and the positive ions constituting the metal salt are alternately arranged, and some of the positive ions (metal ions) are missing. [Chemical Formula 1]: The first bridge structure will be described in detail with reference to Chemical Formula 1. Chemical Formula 1 shows an example of an electrolyte according to this embodiment, which is a mixture of sulfolane as a medium and metal ions Li in the pores of a porous insulator. ＋ and an electrolyte containing a metal salt (sulfolane-Li ＋ The authors list sulfolane-Li as an electrolyte. ＋ In the electrolyte of this system, the first bridge structure is formed by connecting the sulfonyl group (oxygen atom) of sulfolane to Li ＋ Coordinates with sulfolane and Li ＋ and are arranged alternately in one dimension, and in some parts Li ＋ It has a defect where Li is missing (the dashed circle in [Chemical Formula 1]). ＋When the first bridge structure is viewed from the viewpoint of the first bridge structure, the first bridge structure is ＋ is bridged by sulfolane. ＋ Because of the presence of defects, adjacent Li ＋ can move to the defect. ＋ can move sequentially within the first bridge structure, the first bridge structure contributes to efficient transport of metal ions within the electrolyte, and it is thought that better ion conductivity can be achieved.

[0030] In the first bridge structure, the one-dimensional arrangement means, for example, a combination of sulfolane and Li ＋ However, sulfolane and Li ＋ The arrangement of sulfolane and Li is not limited to this. ＋ The arrangement may be two-dimensional or three-dimensional, and more specifically, the linear arrangement may be curved or branched.

[0031] (Method for Confirming First Bridge Structure) The first bridge structure can be confirmed by structural analysis using Raman spectroscopy. As described above, the first bridge structure can be constructed by the coordination of metal ions of a metal salt to a medium. In other words, the first bridge structure can be constructed by the metal ions forming a coordinate bond with a specific functional group of the medium. Therefore, the presence of the first bridge structure can be confirmed by using microscopic Raman spectroscopy to confirm that "the peak derived from the specific vibration of the functional group forming the coordinate bond is shifted to the higher wavenumber side compared to the peak derived from the specific vibration of the functional group in an uncoordinated state."

[0032] For example, the above sulfolane-Li ＋ The first bridge structure in the electrolyte is the SO of the sulfonyl group of the medium in the Raman spectrum. ２Its presence can be confirmed by confirming using microscopic Raman spectroscopy that "peaks (Raman scattering peaks) derived from deformation vibrations are shifted to higher wavenumbers." The presence can be confirmed by the peaks attributable to the O=S=O deformation vibration of the sulfonyl group in a state coordinated to a metal ion being shifted to higher wavenumbers compared to the peaks (known peaks) attributable to the O=S=O deformation vibration of the sulfonyl group in a state not coordinated to a metal ion.

[0033] Also, ethylene carbonate-Li ＋ The presence of the first bridge structure in the electrolyte of the system can be confirmed by the shift of the peak due to the breathing vibration of the heterocycle of the medium (ethylene carbonate) to the higher wavenumber side. ＋ The presence of the first bridge structure in the electrolyte of the system can be confirmed by a shift of the peak due to the stretching vibration of the heterocycle of the medium (GBL) to the higher wavenumber side. The method for confirming the first bridge structure will be described in detail in the Examples.

[0034] (Second Bridge Structure) From the viewpoint of further improving ion conductivity, the electrolyte according to this embodiment preferably has a second bridge structure. In the second bridge structure, positive ions constituting a metal salt and negative ions constituting the metal salt are alternately arranged. [Chemical Formula 2]: The second bridge structure will be described in detail with reference to Chemical Formula 2. Chemical Formula 2 shows the metal ions Li in the pores of the porous insulator as an example of the electrolyte according to this embodiment. ＋ and an electrolyte containing a metal salt composed of an anionic bis(fluorosulfonyl)imide ion (FSI ion) (Li ＋ -FSI-based electrolytes). ＋ In the -FSI-based electrolyte, the second bridge structure is formed by connecting the sulfonyl group (oxygen atom) of the FSI ion to Li ＋ coordinated to the FSI ion and Li ＋ and are arranged alternately in one dimension, and in some parts Li ＋ It has a defect where Li is missing (the dashed circle in [Chemical formula 2]). ＋ When the second bridge structure is viewed from the viewpoint of the second bridge structure, the second bridge structure is ＋is bridged by FSI ions. And Li ＋ Since there are defects, adjacent Li ＋ can move to the defect. ＋ can move sequentially within the second bridge structure, the second bridge structure contributes to efficient transport of metal ions within the electrolyte, and it is thought that better ion conductivity can be achieved.

[0035] In the second bridge structure, the one-dimensional arrangement means, for example, FSI ions and Li ＋ However, the FSI ion and Li ＋ The arrangement of the FSI ion and the Li ion is not limited to this. ＋ The arrangement may be two-dimensional or three-dimensional, and more specifically, the linear arrangement may be curved or branched.

[0036] (Method for Confirming Second Bridge Structure) The second bridge structure can be confirmed by structural analysis using Raman spectroscopy. As described above, the second bridge structure can be constructed by the coordination of a metal ion of a metal salt with a negative ion. In other words, the second bridge structure can be constructed by the metal ion forming a coordinate bond with a specific functional group of the negative ion. Therefore, the presence of the second bridge structure can be confirmed by using microscopic Raman spectroscopy to confirm that "the peak derived from the specific vibration of the functional group forming the coordinate bond is shifted to the higher wavenumber side compared to the peak derived from the specific vibration of the functional group in an uncoordinated state."

[0037] For example, in the case of the metal salt LiFSI, its presence can be confirmed by using microscopic Raman spectroscopy to confirm that "in the Raman spectrum, the peak derived from the S-N-S stretching vibration of the negative ion constituting the metal salt is shifted to a higher wavenumber." For example, when the negative ion constituting the metal salt is an FSI ion, the presence of the first bridge structure can be confirmed by observing that the peak attributed to the S-N-S stretching vibration of the sulfonyl group in a state coordinated to the metal ion is shifted to a higher wavenumber compared to the peak (known peak) attributed to the S-N-S stretching vibration of the sulfonyl group in a state not coordinated to the metal ion. A method for confirming the first bridge structure will be described in detail in the Examples.

[0038] The electrolyte according to this embodiment may be a solid electrolyte.

[0039] The electrolyte according to this embodiment includes a porous insulator, a medium, and a metal salt. The electrolyte according to this embodiment may further include components other than these components (porous insulator, medium, and metal salt) within the scope of the main effects of the present disclosure. These components constituting the electrolyte are described below.

[0040] (Porous insulator) The porous insulator has a medium and a metal salt disposed within its pores. This makes it easier for the electrolyte according to the first embodiment to form a first bridge structure and a second bridge structure that contribute to superior ionic conductivity. The porous insulator has pores. The porous insulator is, for example, at least one selected from the group consisting of a metal organic framework, a zeolite, and a mesoporous silica.

[0041] From the viewpoint of improving the ionic conductivity of the electrolyte, the porous insulator is preferably zeolite or mesoporous silica. Without being bound by a particular theory, the reason is presumed to be as follows: In the electrolyte according to this embodiment, when the electrolyte contains at least one of zeolite and mesoporous silica as the porous insulator (when at least one is present), silanol groups (Si—OH) present on the inner walls of the pores of the zeolite and mesoporous silica are ionized by carriers (positive ions of metal salts, more specifically, Li ＋It is believed that the protons (H etc.) of the silanol groups function as hopping sites. ＋ It is believed that the silanol groups function as hopping sites for the carriers due to the exchange of the silanol groups with the carriers. Therefore, when the electrolyte contains at least one of zeolite and mesoporous silica as a porous insulator, the ionic conductivity of the electrolyte is further improved.

[0042] In the case of zeolite and mesoporous silica among porous insulators, from the viewpoint of improving the ionic conductivity of the electrolyte, the Si / Al ratio is, for example, 5 or more, preferably 15 or more, more preferably 30 or more, even more preferably 100 or more, particularly preferably 500 or more, and very particularly preferably 770 or more. The Si / Al ratio is, for example, 10,000 or less. These upper and lower limit values ​​can be arbitrarily combined to form a numerical range (for example, 5 or more and 10,000 or less). In this specification, the Si / Al ratio refers to the molar ratio of Si (silicon atoms) to Al (aluminum atoms) constituting the porous insulator.

[0043] When the Si / Al ratio is 5 or more, the zeolite and mesoporous silica can have more silanol groups on the inner walls of their pores, which is thought to result in more carrier hopping sites on the inner walls of the zeolite and mesoporous silica, further improving the ionic conductivity of the electrolyte.

[0044] The Si / Al ratio of zeolite and mesoporous silica is measured as follows: The zeolite or mesoporous silica is pulverized to a size that allows measurement, and placed in a nuclear magnetic resonance spectrometer ("ECA400 FT-NMR spectrometer" manufactured by JEOL Ltd.). The magnetic field strength is 9.2 T and the nuclide is: ２９ The NMR spectrum is obtained by measuring under the Si measurement conditions. The Si / Al ratio is obtained by spectral analysis. The zeolite or mesoporous silica used to measure the Si / Al ratio can be measured not only in the raw material state, but also in a state separated from a finished product (for example, an electrolyte or a battery containing an electrolyte (more specifically, a measurement cell battery described later in the Examples)).

[0045] Commercially available metal organic frameworks include, for example, "UiO-67," "HKUST-1," and "F-free MIL-100 (Fe) (KRICT (trademark) F100)" manufactured by Strem Chemicals, and "ZIF-8 (Basolite (registered trademark) (Z1200)" and "MIL-53 (Basolite (registered trademark) (Z1200)" manufactured by MERCK Corporation. A100). Commercially available zeolites include, for example, "HS-690," "HS-642," and "HS-320" manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., and "HSZ-360HUA," "HSZ-385HUA," "HSZ-390HUA," "HSZ-660HOA," "HSZ-840HOA," "HSZ-890HOA," and "HSZ-980HOA" manufactured by Tosoh Corporation. Commercially available mesoporous silicas include, for example, "MCM-41," "MCM-48," "SBA-15," and "SBA-16" manufactured by Sigma-Aldrich.

[0046] (Medium) The medium is an electrically neutral molecule. The medium disperses, dissolves, or forms a solid solution of a metal salt in the electrolyte. The medium is preferably at least one of a sulfonyl-based medium, a carbonate-based medium, an ether-based medium, and a dioxolane-based medium. Among these, a carbonate-based medium is preferred. The sulfonyl-based medium is a medium having a sulfonyl group, and is selected from the group consisting of, for example, sulfolane, dimethyl sulfone, 3-methyl sulfone, and ethyl methyl sulfone. The carbonate-based medium is a cyclic carbonate ester compound (more specifically, a 5- or 6-membered alkylene carbonate compound having 3 to 6 carbon atoms), and is selected from the group consisting of, for example, ethylene carbonate, propylene carbonate, vinylene carbonate, and fluoroethylene carbonate (fluoroethylene carbonate). The carbonate-based medium may have a halogen group (more specifically, a fluoro group, etc.) and a C-C double bond. The chain ether medium is a compound containing two to four ether bonds, and is selected from the group consisting of, for example, 1,2-diethoxyethane and diglyme. The lactone medium is a cyclic ester compound (more specifically, a five- or six-membered ring ester compound having 4 to 7 carbon atoms), and is selected from the group consisting of, for example, γ-butyrolactone and δ-valerolactone. The cyclic ether medium is a five- or six-membered oxygen-containing heterocyclic compound containing two oxygen atoms as ring members, and is selected from the group consisting of dioxolane (1,3-dioxolane) and dioxane (more specifically, 1,3-dioxane, etc.). When the medium is at least one of these, it is likely to form a first bridge structure with the metal ions that constitute the metal salt in the electrolyte. Therefore, in such a case, the ionic conductivity of the electrolyte according to this embodiment is further increased.

[0047] (Metal Salt) The metal salt is at least one selected from the group consisting of alkali metal salts and alkaline earth metal salts. Examples of the metal salt include alkali metal salts (more specifically, lithium metal salts, etc.). Examples of the lithium metal salt include lithium bis(fluorosulfonyl)imide (LiFSI), lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), and lithium tetrafluoroborate (LiBF ４ ), and lithium perchlorate (LiClO ４ Among these, preferred lithium salts are LiFSI and LiTFSI, and more preferred is LiFSI. Examples of alkali metal ions constituting alkali metal salts include Li ＋ , Na ＋ , and K ＋ Examples of alkaline earth metal ions constituting the alkaline earth metal salt include Mg ２＋ The metal ion (positive ion) constituting the metal salt is preferably Li ＋ , K. ＋ , Na ＋ , or Mg ２＋ From the viewpoint of further increasing the ionic conductivity of the electrolyte according to this embodiment, the negative ions constituting the metal salt preferably coordinate with the positive ions constituting the metal salt to form a second bridge structure with the positive ions (metal ions) constituting the metal salt. Examples of the negative ions constituting such metal salts include at least one selected from the group consisting of bis(fluorosulfonyl)imide ions (FSI ions), bis(trifluoromethanesulfonyl)imide ions (TFSI ions), tetrafluoroborate ions, and perchlorate ions.

[0048] (Method for Producing Electrolyte) An example of a method for producing the electrolyte according to the first embodiment will be described. The method for producing the electrolyte according to the first embodiment includes a step of preparing an electrolyte solution containing a metal salt and a medium (electrolyte solution preparation step), and a step of impregnating a porous insulator having pores with the electrolyte (impregnation step).

[0049] - Electrolyte Solution Preparation Step - In the electrolyte solution preparation step, an electrolyte solution containing a metal salt and a medium is prepared. - Impregnation Step - In the impregnation step, a porous insulator having pores is impregnated with the electrolyte solution. As a result, the pores of the porous insulator are filled with the electrolyte solution. If the prepared electrolyte solution is not a liquid at room temperature (25°C) (for example, a solid or quasi-solid (more specifically, a liquid containing a solid)), the electrolyte solution can be heated to a liquid state and then impregnated into the porous insulator.

[0050] Second Embodiment: Battery The battery according to the second embodiment includes the electrolyte according to the first embodiment. The battery according to the second embodiment can further include a positive electrode and a negative electrode in addition to the electrolyte.

[0051] In the battery according to this embodiment, the positive electrode includes a material constituting the positive electrode (more specifically, a positive electrode active material, etc.). The negative electrode includes an alkali metal (more specifically, Li, Na, K) or an alkaline earth metal (more specifically, Mg) as a material constituting the negative electrode (more specifically, a negative electrode active material). The negative electrode includes, for example, an alkali metal or alkaline earth metal simple substance (more specifically, a plate, foil, or layer) or a compound thereof.

[0052] The battery according to this embodiment can be configured as a secondary battery. A conceptual diagram of this case is shown in FIG. 1. As shown in the figure, during charging, metal ions (M ｎ+ (M represents a metal element, and n represents a positive integer): More specifically, Li ＋ , Na ＋ , K. ＋ and Mg ２＋ The metal ions, etc., move from the positive electrode 10 through the electrolyte 12 to the negative electrode 11, converting electrical energy into chemical energy and storing the electricity. During discharge, the metal ions return from the negative electrode 11 through the electrolyte 12 to the positive electrode 10, generating electrical energy.

[0053] The battery according to the second embodiment can be used as a driving or auxiliary power source for, for example, notebook personal computers, PDAs (personal digital assistants), mobile phones, smartphones, cordless phone base units and handset units, video camcorders, digital still cameras, e-books, electronic dictionaries, portable music players, radios, headphones, game consoles, navigation systems, memory cards, cardiac pacemakers, hearing aids, power tools, electric shavers, refrigerators, air conditioners, television receivers, stereos, hot water heaters, microwave ovens, dishwashers, washing machines, dryers, lighting equipment, toys, medical equipment, robots, road conditioners, traffic lights, railroad cars, golf carts, electric carts, and / or electric vehicles (including hybrid vehicles). The battery can also be installed as a power storage power source for buildings such as homes or power generation facilities, or used to supply power to these. In electric vehicles, the converter that converts supplied power into driving force is typically a motor. A control device (controller) that processes information related to vehicle control includes a control device that displays the remaining battery charge based on information about the remaining battery charge. The battery can also be used in a power storage device in a so-called smart grid. Such a power storage device can not only supply power but also store power by receiving power from other power sources. Examples of other power sources that can be used include thermal power generation, nuclear power generation, hydroelectric power generation, solar power generation, wind power generation, geothermal power generation, and / or fuel cells (including biofuel cells).

[0054] Although the embodiments of the present disclosure have been described above, they are merely typical examples. Therefore, it will be readily understood by those skilled in the art that the present disclosure is not limited thereto and that various modifications are possible within the scope of the present disclosure.

[0055] For example, the electrolyte composition, raw materials used in the production, production method, production conditions, electrolyte properties, and battery configuration or structure are examples, and are not limited to these and can be changed as appropriate. For example, batteries include lithium batteries, magnesium batteries, sodium batteries, and potassium batteries, as well as air batteries and fuel cells.

[0056] The present disclosure will be explained in more detail below using examples, but the present disclosure is not limited to these examples.

[0057] Example 1 1. Preparation of Electrolyte Solution (1-1. Raw Materials) The following raw materials were used: Porous insulator: Metal-organic framework (MOF) UiO-67 manufactured by Strem Chemicals: Zr ６ O ４ (OH) ４ (BPDC) ６ MOF represented by (BPDC: biphenyl dicarboxylate) "HKUST-1" manufactured by Strem Chemicals: MOF composed of Cu and 1,3,5-benzenetricarboxylic acid "ZIF-8 (Basolite (Z1200™))" manufactured by MERCK: Zeolite-imidazolate structure (ZIF): MOF composed of Zn and 2-methylimidazole "F-free MIL-100 (Fe) (KRICT™ F100)" manufactured by Strem Chemicals: Fe ３ (O)(OH)(C ９ H ３ O ６ ) ２ : (MOF composed of Fe and 1,3,5-benzenetricarboxylic acid) MERCK "MIL-53 (Basolite A100)": Al(OH)C ８ H ４ O ４-Porous insulator: Zeolite- Fujifilm Wako Pure Chemical Industries, Ltd. "HS-320" (crystal system: Y-type, Si / Al ratio = 5.5, cation species: H; hereinafter also referred to as "HS-320(H)") Fujifilm Wako Pure Chemical Industries, Ltd. "HS-320" (crystal system: Y-type, Si / Al ratio = 5.5, cation species: Na; hereinafter also referred to as "HS-320(Na)") Fujifilm Wako Pure Chemical Industries, Ltd. "HS-642" (crystal system: mordenite, Si / Al ratio = 18, cation species: Na) Fujifilm Wako Pure Chemical Industries, Ltd. "HS-690" (crystal system: mordenite, Si / Al ratio = 180, cation species: H) Tosoh Corporation "HSZ-360HUA" (crystal system: Y-type, Si / Al ratio = 15, cation species: H) "HSZ-385HUA" manufactured by Tosoh Corporation (crystal system: Y-type, Si / Al ratio = 100, cation species: H) "HSZ-390HUA" manufactured by Tosoh Corporation (crystal system: Y-type, Si / Al ratio = 770, cation species: H) "HSZ-660HOA" manufactured by Tosoh Corporation (crystal system: mordenite, Si / Al ratio = 30, cation species: H) "HSZ-840HOA" manufactured by Tosoh Corporation (crystal system: ZSM-5, Si / Al ratio = 40, cation species: H) "HSZ-980HOA" manufactured by Tosoh Corporation (crystal system: beta, Si / Al ratio = 500, cation species: H) -Porous insulator: mesoporous silica- "MCM-41" manufactured by Sigma-Aldrich "MCM-48" manufactured by Sigma-Aldrich・Sigma-Aldrich "SBA-15" ・Sigma-Aldrich "SBA-16" These four mesoporous silicas do not contain artificial Al, so they are silica (SiO ２ Therefore, the Si / Al ratio of these mesoporous silicas is considered to be at least greater than 10,000.

[0058] -Metal Salts- Lithium bis(fluorosulfonyl)imide (manufactured by Kishida Chemical Co., Ltd. (for LBG); hereinafter also referred to as "LiFSI") Lithium bis(trifluoromethanesulfonyl)imide (manufactured by Kishida Chemical Co., Ltd. (for LBG); hereinafter also referred to as "LiTFSI") Lithium hexafluorophosphate (manufactured by Kishida Chemical Co., Ltd. (for LBG); hereinafter also referred to as "LiPF ６" or "LiPF6") Lithium tetrafluoroborate (manufactured by Kishida Chemical Co., Ltd. (for LBG); hereinafter referred to as "LiBF ４ " or "LiBF4") Lithium perchlorate (manufactured by Kishida Chemical Co., Ltd. (for LBG); hereinafter referred to as "LiClO ４ " or "LiClO4")

[0059] - Medium: Sulfonyl-based medium - Sulfolane (manufactured by Kishida Chemical Co., Ltd. (for LBG); hereinafter also referred to as "SL") - Dimethyl sulfone (manufactured by Tokyo Chemical Industry Co., Ltd.; hereinafter also referred to as "DMSO2") - 3-Methylsulfolane (manufactured by Tokyo Chemical Industry Co., Ltd.; hereinafter also referred to as "MSL") - Ethyl methyl sulfone (manufactured by Tokyo Chemical Industry Co., Ltd.; hereinafter also referred to as "EMS") - Medium: Carbonate-based medium - Propylene carbonate (manufactured by Kishida Chemical Co., Ltd.; hereinafter also referred to as "PC") - Ethylene carbonate (manufactured by Kishida Chemical Co., Ltd.; hereinafter also referred to as "EC") - Vinylene carbonate (manufactured by Kishida Chemical Co., Ltd.; hereinafter also referred to as "VC") - Fluoroethylene carbonate (fluoroethylene carbonate) (manufactured by Kishida Chemical Co., Ltd.; hereinafter also referred to as "FEC") - Medium: Lactone-based medium - γ-Butyrolactone (manufactured by Kishida Chemical Co., Ltd.; hereinafter also referred to as "GBL") - Medium: Chain ether medium - Diglyme (manufactured by Kishida Chemical Co., Ltd.) 1,2-dimethoxyethane (manufactured by Kishida Chemical Co., Ltd.; hereinafter also referred to as "DME")

[0060] (1-2. Preparation of Solid Electrolyte) An electrolyte solution was prepared by mixing LiFSI as a metal salt and sulfolane SL as a medium in a molar ratio (medium / metal salt) of 2.0.

[0061] UiO-67, which served as a porous insulator, was dried under vacuum at 250°C. The dried UiO-67 was impregnated with the prepared electrolyte solution, and the electrolyte solution was inserted and filled into the pores of the UiO-67. This resulted in the preparation of a powdered solid electrolyte. This impregnation process was performed by manually mixing the electrolyte solution and the porous insulator using a mortar and pestle. The amount (volume) of the impregnated electrolyte was adjusted to 100% of the micropore volume of the porous insulator (UiO-67), which had been measured in advance. The solid electrolyte was prepared in a glove box in an argon atmosphere.

[0062] (1-3. Fabrication of Test Cell Battery) The prepared powdered solid electrolyte was pressed at 200 MPa using a uniaxial press (Riken Kiki Co., Ltd., "CDM-20PA"). A PET resin mortar equipped with upper and lower punches was used as the press mold for pressing. Specifically, the PET resin mortar had a cylindrical shape and a cylindrical through-hole along the central axis. The punch had a cylindrical shape and was inserted and removed from the through-hole of the mortar, with the tip faces (surfaces perpendicular to the insertion direction) of the upper and lower punches facing each other. The powdered solid electrolyte was set in the through-hole of the mortar so as to be sandwiched between the tip faces of the upper and lower punches. The upper and lower punches were pressed with the uniaxial press to form a solid electrolyte. Furthermore, the upper and lower punches provided on the PET resin mortar were used as blocking electrodes to form a test cell (a test cell). The process of fabricating the test cell was carried out in a glove box in an argon atmosphere.

[0063] [2. Measurement Method and Evaluation Method] (2-1. Morphology of Electrolyte Solution) The appearance of the electrolyte solution (electrolyte solution consisting of a metal salt and a medium) obtained in the solid electrolyte preparation process was visually observed. Furthermore, the container containing the electrolyte solution was tilted, and the behavior of the liquid surface changing to become parallel to the horizontal plane was visually observed. Based on these observation results, the evaluation was made according to the following criteria. (Evaluation criteria) Liquid: The electrolyte has a liquid appearance, with no solid mixed in, and when a cylindrical container containing the electrolyte is tilted so that the bottom of the container forms an angle of 30° with the horizontal, the liquid level of the electrolyte becomes parallel to the horizontal within less than one second after tilting. Sherbet-like: The electrolyte has a liquid and solid appearance mixed in, and when a cylindrical container containing the electrolyte is tilted so that the bottom of the container forms an angle of 30° with the horizontal, the shape of the liquid level of the electrolyte changes within one to sixty seconds after tilting. Solid: The electrolyte has a solid appearance, and when a cylindrical container containing the electrolyte is tilted so that the bottom of the container forms an angle of 30° with the horizontal, the liquid level of the electrolyte does not change even after 10 minutes or more after tilting.

[0064] (2-2. Measurement of Ion Conductivity) - Preparation of Measurement Sample - The measurement cell battery prepared in (1-3. Preparation of Measurement Cell) was enclosed in a laminate with a tab electrode to prepare an ion conductivity measurement cell as a measurement sample.

[0065] -Measurement of ionic conductivity- The ionic conductivity of the measurement sample was measured using an impedance meter (VMP3 manufactured by Biologic). The ionic conductivity was measured at room temperature (25°C) by an AC impedance method. The solid electrolyte of Example 1 had a molar ratio (SL / LiFSI) of 2.0 and an ionic conductivity of 1.9 × 10 －４ The results are shown in Table 1, along with the results of the appearance observation of the electrolyte solution described above. Table 1 shows the molar ratio (SL / LiFSI), the state of the electrolyte solution at room temperature, and the ionic conductivity at room temperature.

[0066] (2-3. Structural Analysis of Electrolytes by Raman Spectroscopy) The electrolytes of Example 1, and the electrolytes of Examples 2 to 8 and Comparative Examples 1 and 2 described below were subjected to structural analysis using Raman spectroscopy. The solid electrolyte formed in (1-3. Preparation of Measurement Cell) was used as a measurement sample for structural analysis. The obtained measurement sample was placed in a microscopic laser Raman spectrometer ("LabRam HR Evolution" manufactured by Horiba, Ltd.). The surface of the measurement sample was irradiated with infrared laser light (wavelength 1064 nm), and the Raman spectrum was measured using an objective lens with a spot diameter of 7 μm. The Raman spectrum may also be measured by irradiating the infrared laser light onto a cut surface formed by cutting the measurement sample (solid electrolyte) for structural analysis.

[0067] 2 shows the results of the electrolytes of Examples 1 to 8 and Comparative Examples 1 and 2 at 550 to 600 cm －１ In the Raman spectrum shown in FIG. 2, the vertical axis represents the Raman intensity (unit: arbitrary intensity), and the horizontal axis represents the Raman shift (unit: cm －１ The Raman spectrum shown in Figure 2 shows the peak at 580-590 cm －１ This peak corresponds to the SO of the sulfonyl group of sulfolane. ２ 560-570 cm due to scissors vibration (O-S-O bending vibration) －１ The peak located nearby was attributed to the peak shifted to the higher wavenumber side.

[0068] 3 shows the results of the electrolytes of Examples 1 to 8 and Comparative Examples 1 and 2 in the range of 680 to 780 cm －１ In the Raman spectrum shown in FIG. 3, the vertical axis represents the Raman intensity (unit: arbitrary intensity), and the horizontal axis represents the Raman shift (unit: cm －１ The Raman spectrum shown in Figure 3 shows the peak at 740-750 cm －１ Nearby peaks and 680-690 cm －１ and a peak around 740-750 cm －１ The peak around 720 to 740 cm is due to the S-N-S stretching vibration of the FSI anion. －１ The peak located nearby was attributed to a shift to the higher wavenumber side.

[0069] (2-4. Determination of Si / Al ratio by nuclear magnetic resonance) In some of the systems (Examples 41 to 46) in which zeolite or mesoporous silica was used as the porous insulator, the Si / Al ratio of the zeolite or mesoporous silica was determined. Specifically, the zeolite or mesoporous silica was pulverized to a degree that allowed measurement. The pulverized zeolite or mesoporous silica was placed in a nuclear magnetic resonance apparatus ("ECA400 FT-NMR apparatus" manufactured by JEOL Ltd.). The magnetic field strength was 9.2 T and the nuclide: ２９ Measured under Si measurement conditions ２９ A Si NMR spectrum was obtained. ２９ The Si / Al ratio was obtained from the peak area intensity ratio of the Si NMR spectrum.

[0070] Examples 2 to 8 and Comparative Examples 1 and 2: Molar Ratio An electrolyte was prepared and its ionic conductivity was measured in the same manner as in Example 1, except that the molar ratio (SL / LiFSI) was changed from 2.0 to the molar ratio shown in Table 1. The appearance of the electrolyte solution obtained in the electrolyte preparation step was also observed. These results are shown in Table 1. Note that when the concentration of the metal salt in the electrolyte solution consisting of the metal salt and the medium is relatively high (i.e., when the concentration of the medium is relatively low), the electrolyte may become a solid or a liquid with a solid precipitated at room temperature (25°C). In such cases, the prepared electrolyte solution was heated (for example, to 100°C) until the solid in the electrolyte solution was completely dissolved, and the liquid was then impregnated. In Example 6, the electrolyte of Example 6 and a negative electrode containing Li ４ Ti ５ O １２ and LiFePO as the positive electrode. ４ A lithium ion secondary battery comprising the above was fabricated. Charging and discharging were carried out at a current of 0.2 C (coulomb). The charging and discharging potential was about 1.8 V.

[0071] [Results: Examples 1 to 8 and Comparative Examples 1 and 2: Molar Ratio] (Ionic Conductivity) Table 1 shows the molar ratio (SL / LiFSI) and the ionic conductivity at room temperature. Figure 4 was created based on Table 1. Figure 4 shows the relationship between the molar ratio (SL / LiFSI) and the ionic conductivity at room temperature. The horizontal axis in Figure 4 shows the molar ratio, and the vertical axis shows the ionic conductivity (unit: S / cm) at room temperature. Note that, for example, 1.0E-03 in the scale of the vertical axis in Figure 4 corresponds to 1.0 x 10 －３ Shows.

[0072]

[0073] In the SL-LiFSI electrolyte, as shown in FIG. 4, the ionic conductivity at room temperature simply increased as the molar ratio (SL / LiFSI) increased from 0.1 to 0.3, decreased as the molar ratio (SL / LiFSI) increased from 0.3 to 2.6, and remained approximately the same as the molar ratio (SL / LiFSI) increased from 2.6 to 9.6. Furthermore, when the ionic conductivity of the electrolyte solution composed of SL and LiFSI in Example 4 was measured, it was found to be below the lower limit of measurement (or below the measurement limit; more specifically, about 10 －７ This value corresponds to the ionic conductivity of an insulator.

[0074] (First Bridge Structure) In the SL-LiFSI electrolyte, as shown in FIG. 2, the peak (Raman scattering peak) due to the O—S—O bending vibration occurs at 560 to 570 cm when the molar ratio (SL / LiFSI) is 2.6 to 9.6. －１ When the molar ratio (SL / LiFSI) is decreased from 0.5 to 2.0, the peak temperature is 580-590 cm －１ In the electrolytes of Examples 1 to 5, the peak due to the O-S-O deformation vibration was shifted to the higher wavenumber side compared to the electrolytes of Comparative Examples 1 and 2. From these results, it can be seen that in the electrolytes of Examples 1 to 8, the peak due to the O-S-O deformation vibration was shifted to the higher wavenumber side. ＋ It is believed that the SL and the SL serving as a medium form a first bridge structure. The first bridge structure is presumed to be due to a specific molar ratio (SL / LiFSI).

[0075] (Second Bridge Structure) In the SL-LiFSI electrolyte, as shown in FIG. 3, the peak (Raman scattering peak) due to the SNS stretching vibration occurs at 720 to 740 cm when the molar ratio (SL / LiFSI) is 2.6 to 9.6. －１ When the molar ratio (SL / LiFSI) is decreased from 0.5 to 2.0, the peak temperature is 740-760 cm －１ In the electrolytes of Examples 1 to 5, the peaks derived from the S-N-S stretching vibrations gradually shifted to the higher wavenumber side as the molar ratio (SL / LiFSI) decreased compared to the electrolytes of Comparative Examples 1 and 2. From these results, it can be seen that in the electrolytes of Examples 1 to 5, the positive ions Li, which constitute the metal salt, ＋ The negative ions of SL and LiFSI are thought to form a second bridge structure. The second bridge structure is presumed to be due to a specific molar ratio (SL / LiFSI).

[0076] Comparison of Examples 1 to 8 with Comparative Examples 1 and 2 The electrolytes of Examples 1 to 8 included UiO-67 as a porous insulator having pores, SL as a medium having sulfonyl groups disposed in the pores, and LiFSI as a metal salt, where the LiFSI as the metal salt was at least one selected from the group consisting of alkali metal salts and alkaline earth metal salts, and the molar ratio of the medium to the metal salt (medium / metal salt) was 0.1 or more and 2.0 or less. In other words, the electrolytes of Examples 1 to 8 were electrolytes that fell within the scope of the invention according to claim 1.

[0077] The ionic conductivity of the electrolytes in Examples 1 to 8 was 1.9 × 10 at room temperature. －４ ~10.1 x 10 －４ S / cm.

[0078] The electrolytes of Comparative Examples 1 and 2 were not included in the scope of the invention according to claim 1. Specifically, the molar ratio of the medium to the metal salt (medium / metal salt) of the electrolytes of Comparative Examples 1 and 2 exceeded 2.0. The ionic conductivity of the electrolytes of Comparative Examples 1 and 2 was 1.2 × 10 at room temperature. －４ S / cm.

[0079] Examples 1 to 8, which fall within the scope of the invention according to claim 1, had higher ionic conductivities at room temperature compared to Comparative Examples 1 and 2, which fall outside the scope of the invention according to claim 1. This demonstrates that the invention according to claim 1 is excellent in ionic conductivity.

[0080] Examples 9 to 14 and Comparative Examples 3 to 5: Porous Insulators Electrolytes were prepared and batteries were fabricated in the same manner as in Example 1, except that UiO-67 as the porous insulator and the molar ratio (medium / metal salt) were changed to the porous insulators (metal organic insulators) and molar ratios shown in Table 2. Ion conductivity was also measured in the same manner as in Example 1. The results are shown in Table 2.

[0081]

[0082] Comparison of Examples 9 to 14 with Comparative Examples 3 to 5 The electrolytes of Examples 9 to 14 included any one of HKUST-1, ZIF-8, and MIL-100(Fe) as a porous insulator (metal-organic framework) having pores, SL as a medium having sulfonyl groups arranged in the pores, and LiFSI as a metal salt, wherein the LiFSI as the metal salt was at least one selected from the group consisting of alkali metal salts and alkaline earth metal salts, and the molar ratio of the medium to the metal salt (medium / metal salt) was 0.1 or more and 2.0 or less. In other words, the electrolytes of Examples 9 to 14 were electrolytes encompassed within the scope of the invention according to claim 1.

[0083] The ion transmission rate of the electrolytes in Examples 9 to 14 was 2.2 × 10 at room temperature. －４ ~4.3 x 10 －４ S / cm.

[0084] The electrolytes of Comparative Examples 3 to 5 were not included in the scope of the invention according to claim 1. Specifically, the molar ratio of the medium to the metal salt (medium / metal salt) of the electrolytes of Comparative Examples 3 to 5 exceeded 2.0. The ionic conductivity of the electrolytes of Comparative Examples 3 to 5 was 0.77 × 10 at room temperature. －４ ~1.7 × 10 －４ S / cm.

[0085] Examples 9 to 14, which fall within the scope of the invention according to claim 1, had higher ionic conductivity at room temperature than Comparative Examples 3 to 5, which fall outside the scope of the invention according to claim 1. This demonstrates that the invention according to claim 1 is excellent in ionic conductivity.

[0086] Examples 15 to 20: Metal Salt and Medium Electrolytes were prepared and batteries were fabricated in the same manner as in Example 1, except that the metal salt LiFSI, the medium SL, and the molar ratio thereof were changed to the metal salt, medium, and molar ratio (medium / metal salt) shown in Table 3. Ion conductivity was also measured in the same manner as in Example 1. The results are shown in Table 3.

[0087]

[0088] The electrolytes of Examples 15 to 20 consisted of UiO-67 as a porous insulator having pores, any of SL, DMSO, MSL, and EMS as a medium having sulfonyl groups arranged in the pores, and LiTFSI, LiBF as a metal salt. ４ , LiClO ４ and LiFSI, the metal salt being at least one selected from the group consisting of alkali metal salts and alkaline earth metal salts, and the molar ratio of the medium to the metal salt (medium / metal salt) was 0.1 or more and 2.0 or less. In other words, the electrolytes of Examples 15 to 20 were electrolytes that fell within the scope of the invention according to claim 1.

[0089] The ionic conductivity of the electrolytes of Examples 15 to 20 was 2.7 × 10 at room temperature. －４ ~3.5 x 10 －４ S / cm.

[0090] Examples 21 to 28 and Comparative Examples 6 and 7: EC-LiFSI / UiO-67 System (Ionic Conductivity) The electrolyte solutions of Examples 21 to 28 were prepared and their ionic conductivities were measured in the same manner as in Example 1, except that the medium was changed from sulfolane (SL) to ethylene carbonate (EC) (manufactured by Kishida Chemical Co., Ltd.) and the molar ratio (EC / LiFSI) shown in Table 4 was used. The appearances of the electrolyte solutions obtained in the electrolyte solution preparation step were also observed. The results are shown in Table 4.

[0091]

[0092] Table 4 shows the relationship between the molar ratio (EC / LiFSI) and the ionic conductivity at room temperature. Figure 5 was created based on Table 4. Figure 5 shows the relationship between the molar ratio (EC / LiFSI) and the ionic conductivity at room temperature. For the EC-LiFSI electrolyte, as shown in Figure 5, the ionic conductivity at room temperature increased simply as the molar ratio (EC / LiFSI) increased from 0.1 to 0.5, decreased simply as the molar ratio (EC / LiFSI) increased from 0.5 to 4.0, and remained almost constant as the molar ratio (EC / LiFSI) increased from 4.0 to 10.0.

[0093] The electrolytes of Examples 21 to 28 included UiO-67 as a porous insulator having pores, EC as a medium disposed in the pores, and LiFSI as a metal salt, the LiFSI as the metal salt being at least one selected from the group consisting of alkali metal salts and alkaline earth metal salts, and the molar ratio of the medium to the metal salt (medium / metal salt) was 0.1 or more and 2.0 or less. In other words, the electrolytes of Examples 21 to 28 were electrolytes encompassed within the scope of the invention according to claim 1.

[0094] The ionic conductivity of the electrolytes of Examples 21 to 28 was 3.7 × 10 at room temperature. －４ ~10 x 10 －４ S / cm.

[0095] The electrolytes of Comparative Examples 6 and 7 were not included in the scope of the invention according to claim 1. Specifically, the molar ratio of the medium to the metal salt (medium / metal salt) of the electrolytes of Comparative Examples 6 and 7 exceeded 2.0. The ionic conductivity of the electrolytes of Comparative Examples 6 and 7 was 2.7 × 10 at room temperature. －４ ~2.9 x 10 －４ S / cm.

[0096] Examples 21 to 28, which fall within the scope of the invention according to claim 1, had higher ionic conductivity at room temperature than Comparative Examples 6 to 7, which fall outside the scope of the invention according to claim 1. This demonstrates that the invention according to claim 1 is excellent in ionic conductivity.

[0097] Furthermore, the integral value of the graph showing ionic conductivity in Fig. 5 was larger than the integral value of the graph showing ionic conductivity in Fig. 4. This shows that the electrolytes of Examples 21 to 28 exhibit higher ionic conductivity than the electrolytes of Examples 1 to 8 (i.e., the EC-LiSFI electrolyte has higher ionic conductivity than the SL-LiSFI electrolyte).

[0098] (Structural Analysis by Raman Spectroscopy) -First Bridge Structure- Furthermore, for the electrolytes of Examples 23, 25 to 26 and Comparative Example 6, structural analysis of the electrolytes was carried out by Raman spectroscopy in the same manner as in Example 1. －１ In the Raman spectrum shown in FIG. 6, the vertical axis represents the Raman intensity (unit: arbitrary intensity), and the horizontal axis represents the Raman shift (unit: cm －１ The Raman spectrum shown in FIG. －１ This peak was due to the ring breathing vibration of ethylene carbonate (EC) (heterocyclic breathing vibration) at 895 cm －１ The peak located nearby was attributed to the peak shifted to the higher wavenumber side.

[0099] In the EC-LiFSI electrolyte, as shown in FIG. 6, when the molar ratio (EC / LiFSI) is 0.3 to 1.0 (Examples 23, 25 to 26), there is mainly one peak (Raman scattering peak) due to the breathing vibration of the heterocycle of EC, and the peak is located at 900 to 910 cm －１ That is, in the electrolytes of Examples 23, 25 and 26, the peak due to the breathing vibration was observed to be shifted to the higher wavenumber side. In contrast, when the molar ratio (EC / LiFSI) was 10 (Comparative Example 6), two peaks due to the breathing vibration were present, each at 895 cm －１ Around 900-910cm －１ That is, for the electrolyte of Comparative Example 6, the peak derived from the respiratory vibration was mainly observed, and a peak shifted to the higher wavenumber side was slightly observed.

[0100] From the results of FIG. 6, in the electrolytes of Examples 23 and 25 to 26, Li constituting the metal salt ＋ It is believed that the EC serving as a medium forms a first bridge structure, and this bridge structure is presumed to be due to the molar ratio (EC / LiFSI).

[0101] - Second bridge structure - Furthermore, FIG. 7 shows the 680 to 800 cm of the electrolytes of Examples 23, 25 to 26 and Comparative Example 6. －１ In the Raman spectrum shown in FIG. 7, the vertical axis represents the Raman intensity (unit: arbitrary intensity), and the horizontal axis represents the Raman shift (unit: cm －１ The Raman spectrum shown in FIG. －１ This peak was derived from the SN-S stretching vibration of the FSI anion at 710 to 740 cm －１ The peak located nearby was attributed to a peak shifted to the higher wavenumber side.

[0102] In the EC-LiFSI electrolyte, as shown in FIG. 7 , when the molar ratio (EC / LiFSI) was 0.3 to 1.0 (Examples 23, 25, and 26), the peaks (Raman scattering peaks) derived from the SNS stretching vibration of the FSI anion were mainly peaks shifted to higher wavenumbers. That is, in the electrolytes of Examples 23, 25, and 26, the peaks derived from the deflection vibration were mainly peaks shifted to higher wavenumbers. In contrast, when the molar ratio (EC / LiFSI) was 10 (Comparative Example 6), the peaks derived from the stretching vibration were mainly peaks derived from the stretching vibration. That is, in the electrolyte of Comparative Example 6, the peaks derived from the breathing vibration were mainly observed.

[0103] From the results of FIG. 7, in the electrolytes of Examples 23, 25 to 26, Li constituting the metal salt ＋ It is believed that the FSI anions form a second bridge structure, and this second bridge structure is presumed to be due to the molar ratio (EC / LiFSI).

[0104] Examples 29 to 32: EC-LiFSI / MOF System Electrolytes of Examples 29 to 32 were prepared and their ionic conductivities were measured in the same manner as in Example 1, except that sulfolane (SL) as the medium was changed to ethylene carbonate (EC) (manufactured by Kishida Chemical Co., Ltd.), the molar ratio (SL / LiFSI) was changed to the molar ratio (EC / LiFSI) shown in Table 5, and UiO-67 as the porous insulator was changed to a metal-organic framework (MOF) shown in Table 5. The results are shown in Table 5.

[0105]

[0106] The electrolytes of Examples 29 to 32 comprised any one of HKUST-1, ZIF-8, MIL-100(Fe), and MIL-53 as a porous insulator (metal-organic framework) having pores, EC as a medium disposed in the pores, and LiFSI as a metal salt, wherein the LiFSI as the metal salt was at least one selected from the group consisting of alkali metal salts and alkaline earth metal salts, and the molar ratio of the medium to the metal salt (medium / metal salt) was 0.1 or more and 2.0 or less. In other words, the electrolytes of Examples 29 to 32 were electrolytes encompassed within the scope of the invention according to claim 1.

[0107] Examples 33 to 40 and Comparative Examples 8 to 9: EC-LiFSI / Zeolite System Electrolytes of Examples 33 to 40 and Comparative Examples 8 to 9 were prepared and their ionic conductivities were measured in the same manner as in Example 1, except that sulfolane (SL) as the medium was changed to ethylene carbonate (EC) (manufactured by Kishida Chemical Co., Ltd.), the molar ratio (SL / LiFSI) was changed to the molar ratio (EC / LiFSI) shown in Table 6, UiO-67 as the porous insulator was changed to HS-690, a zeolite, and the drying temperature of the porous insulator under vacuum was changed from 250°C to 300°C. The appearance of the electrolyte solution obtained in the electrolyte solution preparation step was also observed. The results are shown in Table 6.

[0108]

[0109] The electrolytes of Examples 33 to 40 comprised HS-690 as a porous insulator (zeolite) having pores, EC as a medium disposed in the pores, and LiFSI as a metal salt, the LiFSI as the metal salt being at least one selected from the group consisting of alkali metal salts and alkaline earth metal salts, and the molar ratio of the medium to the metal salt (medium / metal salt) was 0.1 or more and 2.0 or less. In other words, the electrolytes of Examples 29 to 32 were electrolytes encompassed within the scope of the invention according to claim 1. The ionic conductivity of the electrolytes of Examples 33 to 40 was 9.7 × 10 at room temperature. －４ ~54 x 10 －４ S / cm.

[0110] The electrolytes of Comparative Examples 8 and 9 were not included in the scope of the invention according to claim 1. Specifically, the molar ratio of the medium to the metal salt (medium / metal ratio) of the electrolytes of Comparative Examples 8 and 9 exceeded 2.0. The ionic conductivity of the electrolytes of Comparative Examples 8 and 9 was 2.5 × 10 at room temperature. －４ ~2.8 x 10 －４ S / cm.

[0111] Examples 33 to 40, which fall within the scope of the invention according to claim 1, had higher ionic conductivity at room temperature than Comparative Examples 8 and 9, which do not fall within the scope of the invention according to claim 1.

[0112] In addition, the electrolyte was changed to that of Example 37, and Li was used as the negative electrode. ４ Ti ５ O １２ and LiFePO as the positive electrode. ４ A battery of Example 37 was fabricated in the same manner as the battery of Example 1 (cell for measuring ionic conductivity), except that a battery of Example 37 was used. The resulting battery of Example 37 was charged and discharged at a current of 0.1 C. It was found that the battery of Example 37 was capable of being charged and discharged at about 1.8 V.

[0113] Examples 41 to 44: EC-LiFSI / Zeolite System Electrolytes of Examples 41 to 46 were prepared and their ionic conductivities were measured in the same manner as in Example 1, except that sulfolane (SL) as the medium was changed to ethylene carbonate (EC) (manufactured by Kishida Chemical Co., Ltd.), the molar ratio (SL / LiFSI) was changed to the molar ratio (EC / LiFSI) shown in Table 7, and UiO-67 as the porous insulator was changed to zeolite (any of HS-320(H), HSZ-360HUA, HSZ-660HOA, HSZ-385HUA, HSZ-980HOA, and HSZ-390HUA). The results are shown in Table 7.

[0114]

[0115] The electrolytes of Examples 41 to 46 comprised any one of HS-320(H), HSZ-360HUA, HSZ-660HOA, HSZ-385HUA, HSZ-980HOA, and HSZ-390HUA as a porous insulator (zeolite) having pores, EC as a medium disposed in the pores, and LiFSI as a metal salt, wherein the LiFSI as the metal salt was at least one selected from the group consisting of alkali metal salts and alkaline earth metal salts, and the molar ratio of the medium to the metal salt (medium / metal salt) was 0.1 or more and 2.0 or less. In other words, the electrolytes of Examples 41 to 46 were electrolytes encompassed within the scope of the invention according to claim 1.

[0116] The ionic conductivity of the electrolytes of Examples 41 to 46 was 1.1 × 10 at room temperature. －３ ~8.5 x 10 －３ S / cm, which increased with increasing Si / Al ratio. This trend suggests that the larger the Si / Al ratio, the more silanol groups are present on the inner walls of the pores of the porous insulator, resulting in the carrier (Li ＋ ) hopping sites will increase.

[0117] The ionic conductivity of the electrolytes of Examples 41 to 46 (EC-LiFSi / zeolite system, molar ratio 0.3) was 1.1 × 10 －３ ~8.5 x 10 －３On the other hand, the ionic conductivity of the electrolyte of Example 6 (EC-LiFSi / metal organic framework, molar ratio 0.3) is 1.01 × 10 －３ Therefore, it can be seen that when the porous insulator is a zeolite system, the ionic conductivity can be improved more than when it is a metal organic framework system.

[0118] Examples 48 to 63: Alkali Metal Salt-Medium / Zeolite (HS-690) System The electrolytes of Examples 48 to 63 were prepared and their ionic conductivities were measured in the same manner as in Example 1, except that sulfolane (SL) as the medium was changed to a medium shown in Table 8, LiSFI as the metal salt was changed to an alkali metal salt shown in Table 8, and UiO-67 as the porous insulator was changed to zeolite (HS-690). The results are shown in Table 8.

[0119]

[0120] The electrolytes of Examples 48 to 63 included HS-690 as a porous insulator (zeolite) having pores, any one of PC, VC, FEC, EC, GBL, diglyme, and DME as a medium disposed in the pores, and any one of LiFSI, LiTFSI, LiPF6, LiBF4, and LiClO4 as a metal salt, with a molar ratio of the medium to the metal salt (medium / metal salt) of 0.1 or more and 2.0 or less. In other words, the electrolytes of Examples 48 to 63 were electrolytes encompassed within the scope of the invention according to claim 1.

[0121] Examples 64 to 69: EC-LiFSI / mesoporous silica system Electrolytes of Examples 64 to 69 were prepared and their ionic conductivities were measured in the same manner as in Example 1, except that sulfolane (SL) as the medium was changed to a medium shown in Table 9, and Ui0-67 as the porous insulator was changed to mesoporous silica shown in Table 9. The results are shown in Table 9.

[0122]

[0123] The electrolytes of Examples 64 to 69 contained any one of MCM-48, SBA-15, MCM-41, and SBA-16 as a porous insulator (mesoporous silica) having pores, EC as a medium disposed in the pores, and LiFSI as a metal salt, with the molar ratio of the medium to the metal salt (medium / metal salt) being 0.1 or more and 2.0 or less. In other words, the electrolytes of Examples 64 to 69 were electrolytes encompassed within the scope of the invention according to claim 1.

[0124] The ionic conductivity of the electrolytes of Examples 65 and 67 to 69 (EC-LiFSi / mesoporous silica system, molar ratio 0.5) was 3.1 × 10 －３ ~3.7 × 10 －３ On the other hand, the ionic conductivity of the electrolyte of Example 5 (EC-LiFSi / metal organic framework, molar ratio 0.5) is 0.94 × 10 －３ S / cm. This shows that the ionic conductivity can be improved more in a system in which the porous insulator is mesoporous silica than in a system in which the porous insulator is a metal organic framework.

[0125] Examples 71 to 80 and Comparative Example 10: SL-LiFSI / Zeolite System Electrolytes of Examples 71 to 80 were prepared and their ionic conductivities were measured in the same manner as in Example 1, except that Ui0-67 as the porous insulator was changed to a zeolite shown in Table 10 and the molar ratio (SL-LiFSI) was changed to a molar ratio shown in Table 10. The results are shown in Table 10.

[0126]

[0127] The electrolytes of Examples 71 to 80 comprised any one of HS-690, HS-642, HS-320(Na), HSZ-980HOA, and HSZ-840HOA as a porous insulator (zeolite) having pores, SL as a medium disposed in the pores, and LiFSI as a metal salt, and the molar ratio of the medium to the metal salt (medium / metal salt) was 0.1 or more and 2.0 or less. In other words, the electrolytes of Examples 71 to 80 were electrolytes encompassed within the scope of the invention according to claim 1. The ionic conductivity of the electrolytes of Examples 71 to 80 was 3.3 × 10 at room temperature. －４ ~42 x 10 －４ S / cm.

[0128] The electrolyte of Comparative Example 10 was an electrolyte not included in the scope of the invention according to claim 1. Specifically, the molar ratio of the medium to the metal salt (medium / metal ratio) of the electrolyte of Comparative Example 10 was greater than 2.0. The ionic conductivity of the electrolyte of Comparative Example 10 was 1.1 × 10 at room temperature. －４ S / cm.

[0129] Examples 71 to 80, which fall within the scope of the invention according to claim 1, had higher ionic conductivity at room temperature than Comparative Example 10, which does not fall within the scope of the invention according to claim 1.

[0130] Furthermore, the integral value of the graph (not shown) showing the ionic conductivity of Examples 71 to 75 (SL-LiFSI / zeolite-based, molar ratio 0.1 to 1.0) in Table 10 was greater than the integral value of the graph ( FIG. 4 ) showing the ionic conductivity of Examples 4 to 8 (SL-LiFSI / metal organic framework-based, molar ratio 0.1 to 1.0) in Table 1. This demonstrates that the electrolytes of Examples 71 to 75 exhibit higher ionic conductivity than the electrolytes of Examples 4 to 8 (i.e., zeolite-based electrolytes have higher ionic conductivity than metal organic framework-based electrolytes).

[0131] Examples 81 to 87 and Comparative Example 11: SL-LiFSI / mesoporous silica system Electrolytes of Examples 81 to 87 and Comparative Example 11 were prepared and their ionic conductivities were measured in the same manner as in Example 1, except that Ui0-67 as the porous insulator was replaced with mesoporous silica shown in Table 11 and the molar ratio (SL / LiFSI) was changed to the molar ratio shown in Table 11. The results are shown in Table 11.

[0132]

[0133] The electrolytes of Examples 81 to 87 comprised any one of MCM-48, SBA-15, MCM-41, and SBA-16 as a porous insulator (mesoporous silica) having pores, SL as a medium disposed in the pores, and LiFSI as a metal salt, with the molar ratio of the medium to the metal salt (medium / metal salt) being 0.1 or more and 2.0 or less. In other words, the electrolytes of Examples 81 to 87 were electrolytes encompassed within the scope of the invention according to claim 1. The ionic conductivity of the electrolytes of Examples 81 to 87 was 18×10 at room temperature. －４ ~120 x 10 －４ S / cm.

[0134] The electrolyte of Comparative Example 11 was an electrolyte not included in the scope of the invention according to claim 1. Specifically, the molar ratio of the medium to the metal salt (medium / metal ratio) of the electrolyte of Comparative Example 11 was greater than 2.0. The ionic conductivity of the electrolyte of Comparative Example 11 was 0.82 × 10 at room temperature. －４ S / cm.

[0135] Examples 81 to 87, which fall within the scope of the invention according to claim 1, had higher ionic conductivity at room temperature than Comparative Example 11, which does not fall within the scope of the invention according to claim 1.

[0136] Furthermore, the integral value of the graph (not shown) showing the ionic conductivity of Examples 81 to 84 in Table 11 (SL-LiFSI / mesoporous silica system, molar ratio 0.2 to 1.0) was greater than the integral value of the graph ( FIG. 4 ) showing the ionic conductivity of Examples 4 to 7 in Table 1 (SL-LiFSI / metal organic framework system, molar ratio 0.2 to 1.0). This demonstrates that the electrolytes of Examples 81 to 84 exhibit higher ionic conductivity than the electrolytes of Examples 4 to 7 (i.e., mesoporous silica-based electrolytes have higher ionic conductivity than metal organic framework-based electrolytes).

[0137] The electrolyte and battery according to the present disclosure include the following: <1> An electrolyte comprising a porous insulator having pores, and a medium and a metal salt disposed in the pores, wherein the metal salt is at least one selected from the group consisting of alkali metal salts and alkaline earth metal salts, and the molar ratio of the medium to the metal salt (medium / metal salt) is 0.1 or more and 2.0 or less. <2> The electrolyte according to <1>, wherein the medium is at least one of: a sulfonyl-based medium selected from the group consisting of sulfolane, dimethyl sulfone, 3-methyl sulfone, and ethyl methyl sulfone; a carbonate-based medium selected from the group consisting of ethylene carbonate, propylene carbonate, vinylene carbonate, and fluoroethylene carbonate; a chain ether-based medium selected from the group consisting of 1,2-diethoxyethane and diglyme; a lactone-based medium selected from the group consisting of γ-butyrolactone and δ-valerolactone; and a cyclic ether-based medium selected from the group consisting of 1,3-dioxolane and 1,3-dioxane. <3> The electrolyte according to <1> or <2>, wherein the metal salt is a lithium salt. <4> The electrolyte according to any one of <1> to <3>, wherein the porous insulator is at least one selected from the group consisting of a metal organic framework, a zeolite, and mesoporous silica. <5> The electrolyte according to <1>, wherein the positive ions constituting the metal salt are Li ＋ , K. ＋ , Na ＋ , or Mg ２＋ <6> The electrolyte according to any one of <1> to <4>, wherein the negative ion constituting the metal salt is at least one selected from the group consisting of a bis(fluorosulfonyl)imide ion, a TFSI ion, a tetrafluoroborate ion, and a perchlorate ion. <7> The electrolyte according to any one of <1> to <6>, wherein the electrolyte is a solid electrolyte. <8> The medium is a sulfonyl medium having at least one sulfonyl group selected from the group consisting of sulfolane, dimethyl sulfone, 3-methyl sulfone, and ethyl methyl sulfone, and wherein the Raman spectrum shows that the SO of the sulfonyl group is ２The electrolyte according to any one of <1> to <7>, wherein a peak derived from bending vibrations is shifted to a higher wavenumber side. <9> The electrolyte according to any one of <1> to <8>, wherein an anion constituting the metal salt is a bis(fluorosulfonyl)imide ion or a bis(trifluoromethanesulfonyl)imide ion, and wherein, in a Raman spectrum, a peak derived from S-N-S stretching vibrations of the anion constituting the metal salt is shifted to a higher wavenumber side. <10> The electrolyte according to any one of <1> to <9>, wherein the porous insulator is either a zeolite or a mesoporous silica. <11> The electrolyte according to any one of <1> to <10>, wherein the porous insulator is either a zeolite or a mesoporous silica, and wherein the SiAl ratio of the zeolite and the mesoporous silica is 5.0 or more. <12> The electrolyte according to any one of <1> to <11>, wherein the medium is at least one carbonate-based medium selected from the group consisting of ethylene carbonate, propylene carbonate, vinylene carbonate, and fluoroethylene carbonate. <13> The electrolyte according to any one of <1> to <12>, wherein the medium is at least one carbonate-based medium selected from the group consisting of ethylene carbonate, propylene carbonate, vinylene carbonate, and fluoroethylene carbonate, and wherein, in the Raman spectrum, a peak derived from the breathing vibration of a heterocycle possessed by the carbonate-based medium is shifted to a higher wavenumber side. <14> A battery comprising the electrolyte according to any one of <1> to <13>.

[0138] Batteries including the electrolyte according to the present disclosure can be used in a variety of fields where electricity storage is anticipated. Although merely illustrative, batteries (particularly secondary batteries) including the electrolyte according to the present disclosure can be used in the fields of electricity, information, and communications where electric and electronic devices are used (for example, electric and electronic devices or mobile devices including mobile phones, smartphones, laptops, digital cameras, activity meters, arm computers, electronic paper, wearable devices, RFID tags, card-type electronic money, smart watches, and other small electronic devices), household and small industrial applications (for example, power tools, golf carts, and household, nursing care, and industrial robots), large industrial applications (for example, forklifts, elevators, and port cranes), transportation systems (for example, hybrid cars, electric cars, buses, trains, electrically assisted bicycles, and electric motorcycles), power system applications (for example, various power generation systems, road conditioners, smart grids, and general household installation-type power storage systems), medical applications (medical devices such as earphones and hearing aids), pharmaceutical applications (medical management systems), and the IoT field, space and deep-sea applications (for example, space probes, submersible research vessels, and the like).

Claims

1. A porous insulator having pores, and a medium and a metal salt disposed within the pores; the metal salt is at least one selected from the group consisting of alkali metal salts and alkaline earth metal salts, An electrolyte, wherein the molar ratio of said medium to said metal salt (medium / metal salt) is 0.1 or more and 2.0 or less.

2. The medium is a sulfonyl medium selected from the group consisting of sulfolane, dimethyl sulfone, 3-methyl sulfone, and ethyl methyl sulfone; a carbonate-based medium selected from the group consisting of ethylene carbonate, propylene carbonate, vinylene carbonate, and fluoroethylene carbonate; a chain ether medium selected from the group consisting of 1,2-diethoxyethane and diglyme; A lactone medium selected from the group consisting of gamma-butyrolactone, and delta-valerolactone; and A cyclic ether medium selected from the group consisting of 1,3-dioxolane and 1,3-dioxane. The electrolyte according to claim 1 ,

3. The electrolyte of claim 1 , wherein the metal salt is a lithium salt.

4. The electrolyte according to claim 1 , wherein the porous insulator is at least one selected from the group consisting of a metal-organic framework, a zeolite, and a mesoporous silica.

5. The positive ion constituting the metal salt is Li ＋ , K ＋ , Na ＋ , or Mg ２＋ 2. The electrolyte of claim 1 ,

6. 2. The electrolyte according to claim 1, wherein the negative ion constituting the metal salt is at least one selected from the group consisting of a bis(fluorosulfonyl)imide ion, a bis(trifluoromethanesulfonyl)imide ion, a tetrafluoroborate ion, and a perchlorate ion.

7. 10. The electrolyte of claim 1 which is a solid electrolyte.

8. the medium is a sulfonyl-based medium having at least one sulfonyl group selected from the group consisting of sulfolane, dimethyl sulfone, 3-methyl sulfone, and ethyl methyl sulfone; In the Raman spectrum, the sulfonyl group SO ２ The electrolyte according to claim 1 , wherein a peak derived from bending vibration is shifted to a higher wave number side.

9. the negative ion constituting the metal salt is a bis(fluorosulfonyl)imide ion or a bis(trifluoromethanesulfonyl)imide ion, 2. The electrolyte according to claim 1, wherein in a Raman spectrum, a peak derived from the SNS stretching vibration of the negative ions constituting the metal salt is shifted to a higher wave number side.

10. The electrolyte of claim 1 , wherein the porous insulator is one of a zeolite and a mesoporous silica.

11. the porous insulator is one of zeolite and mesoporous silica, 2. The electrolyte of claim 1, wherein the zeolite and the mesoporous silica have a Si / Al ratio of 5.0 or more.

12. 2. The electrolyte of claim 1, wherein the medium is a carbonate-based medium selected from the group consisting of ethylene carbonate, propylene carbonate, vinylene carbonate, and fluoroethylene carbonate.

13. the medium is at least one carbonate-based medium selected from the group consisting of ethylene carbonate, propylene carbonate, vinylene carbonate, and fluoroethylene carbonate; 2. The electrolyte according to claim 1, wherein in a Raman spectrum, a peak derived from the breathing vibration of a heterocycle contained in the carbonate-based medium is shifted to a higher wavenumber side.

14. A battery comprising the electrolyte according to any one of claims 1 to 13.