JP4904667B2 - Method for producing solid polymer electrolyte - Google Patents

Description

  The present invention relates to a solid polymer electrolyte excellent in ion conductivity, and more specifically, a solid polymer electrolyte used for a fuel cell, water electrolysis, salt electrolysis, oxygen concentrator, humidity sensor, gas sensor, and the like, and a method for producing the same. It is about. The present invention also relates to a solid polymer electrolyte membrane having excellent ion conductivity.

  Conventionally, solid polymer electrolytes are known as proton conductive electrolytes. This solid polymer electrolyte has an electrolyte group in the bond chain of the solid polymer material, and this electrolyte group is firmly bonded to a specific ion or selectively transmits a cation or an anion. Therefore, it is formed into particles, fibers, or membranes, and is used for various applications such as electrodialysis, diffusion dialysis, and battery membranes.

For example, a solid polymer electrolyte membrane obtained by forming a solid polymer electrolyte into a film shape is used for salt electrolysis, a solid polymer fuel cell, or the like. Among them, the polymer electrolyte fuel cell is attracting attention as a clean and highly efficient power source because it has high energy conversion efficiency and generates almost no harmful substances, and has been actively researched in recent years. .
Examples of the solid polymer electrolyte membrane include a hydrocarbon electrolyte membrane and a fluorine-containing electrolyte membrane.

  As the fluorine-containing electrolyte membrane, there is a type having a sulfonic acid group, a carboxylic acid group, or the like as an electrolyte group. A fluorine-based sulfonic acid membrane is generally used. As such membranes, membranes represented by Nafion (registered trademark, DuPont) membrane, Flemion (registered trademark, Asahi Glass Co., Ltd.) membrane, Aciplex (registered trademark, Asahi Kasei Co., Ltd.) membrane and the like are widely used.

  The structure of this type of fluorinated sulfonic acid film is maintained due to the crystallinity of the perfluoroalkylene chain, but because it is a non-crosslinked structure, the electrolyte group in the side chain part is a crosslinked carbonized carbon. The degree of freedom is greater than that of hydrogen-based electrolyte membranes. Therefore, in an ionized state, a strongly hydrophobic main chain portion and a hydrophilic electrolyte group coexist, and the electrolyte group associates in the fluorocarbon matrix to form an ion cluster. The ion cluster has a structure in which spherical clusters of about several nm are connected by channels having a narrow interval of about 1 nm.

  Proton conductivity can be expressed by moving protons in the water (cluster water) stored in the spherical clusters. That is, the higher the water content in the membrane, that is, the larger the cluster diameter in the membrane and the greater the amount of cluster water, the higher the proton conductivity.

  In addition, since this type of fluorine-containing sulfonic acid film has a non-crosslinked structure as described above, generally, the molecular movement in the film is facilitated at a high temperature of 100 ° C. or more, and the structure changes, resulting in film strength. Has the property of decreasing.

  Therefore, for example, in Patent Document 1 below, in order to improve the film strength, the fluorine-containing electrolyte membrane is crosslinked by heating the fluorine-containing electrolyte membrane at 180 ° C. or in the presence of a radical generator, A technique for applying this crosslinked membrane to a polymer electrolyte fuel cell is disclosed.

  Further, in Patent Document 2 below, in order to obtain a solid polymer electrolyte having excellent structural stability at high temperatures and high ionic conductivity, a polyvinylidene fluoride resin molded body having a crosslinked structure by electron beam irradiation or the like is disclosed. A technique for impregnating or swelling an electrolyte or a mixture of an electrolyte and a plasticizer is disclosed.

  By the way, when a solid polymer electrolyte is applied to a solid polymer fuel cell, and this solid polymer fuel cell is used as an in-vehicle power source for an electric vehicle, the cooling system is made compact and the electrode catalyst is improved in CO resistance. In order to increase the efficiency and the like, it is desired that the battery operating temperature be 100 ° C. or higher. At such a high temperature, the vapor pressure of water becomes high, so if the internal pressure of the battery is set to a realistic level, the relative humidity of the atmosphere decreases, and the solid polymer electrolyte membrane has sufficient proton conductivity even in a low humidity environment. It is necessary to have.

  However, since solid polymer electrolyte membranes such as conventional Nafion membranes have proton conductivity when they are hydrated, the moisture content in the membrane is not sufficient under high temperature and low humidity conditions of 100 ° C. or higher. There arises a problem that the conductivity is lowered. In addition, since it is a non-crosslinked structure, if the amount of hydrophilic sulfonic acid group introduced is increased too much in order to improve proton conductivity, the membrane will swell too much or become soluble in water. There arises a problem that the practical strength is lowered. Furthermore, there is a problem in use as a solid polymer electrolyte membrane over a long period of time due to the creep of the membrane at high temperatures.

  Moreover, since the solid polymer electrolyte membrane disclosed in Patent Document 1 is crosslinked by heating, the strength of the membrane is improved, but it cannot be said that the improvement in conductivity is sufficient. Even when the polymer electrolyte membrane is applied to a polymer electrolyte fuel cell, there is a problem that sufficient battery performance cannot be obtained under high temperature and low humidity conditions.

  Furthermore, since the solid polymer electrolyte disclosed in Patent Document 2 is obtained by impregnating or swelling a polyvinylidene fluoride resin molded body having a crosslinked structure with an electrolyte or a mixture of an electrolyte and a plasticizer, it is produced by a reaction. In a polymer electrolyte fuel cell in which a substance such as water moves inside the battery, there is a problem that the electrolyte etc. falls off and the conductivity is lowered and cannot be put to practical use.

  As described above, when a conventional solid polymer electrolyte is applied to a solid polymer fuel cell, sufficient battery performance cannot be obtained because the conductivity of the solid polymer electrolyte is not sufficient under high temperature and low humidity conditions. It is thought to be caused by this.

  Therefore, in Patent Document 3 below, for the purpose of obtaining a solid polymer electrolyte having a large ion cluster diameter, excellent conductivity and excellent mechanical strength, the crystalline melting point or softening point of the solid polymer electrolyte is ± 50. It is disclosed to perform electron beam or radiation treatment in a temperature range of ° C. As a result, the polymer chain is simultaneously cleaved and recombined, and the ion clusters in the solid polymer electrolyte are rearranged to finally form a solid polymer electrolyte in which a bridge is formed in the polymer chain. Therefore, this solid polymer electrolyte has a large cluster diameter, and a path advantageous for ion migration is formed, thereby improving the conductivity. Moreover, since it is bridge | crosslinked, mechanical strength improves. At the same time, Patent Document 3 discloses that the solid polymer electrolyte is subjected to an electron beam or radiation treatment and then subjected to a heat treatment in the temperature range of the crystalline melting point or softening point ± 50 ° C. of the solid polymer electrolyte. . This also causes breakage and recombination of the polymer chains at the same time, rearranges the ion clusters in the solid polymer electrolyte, and finally becomes a solid polymer electrolyte in which a bridge is formed in the polymer chain. Therefore, this solid polymer electrolyte has a large cluster diameter, and a path advantageous for ion migration is formed, thereby improving the conductivity. Moreover, since it is bridge | crosslinked, mechanical strength improves.

JP-A-6-275301 JP-A-9-302134 JP 2002-124272 A

  According to the knowledge obtained by the present inventor, in the technique disclosed in Patent Document 3, although the ion cluster diameter in the solid polymer electrolyte is large, the regularity and orientation of the ion cluster are not sufficient, so There was a limit to the improvement of sex. That is, simply increasing the ion cluster diameter has been a problem.

  An object of the present invention is to further improve the ionic conductivity of a solid polymer electrolyte.

  The inventors have found that the regularity and orientation of the ion clusters in the electrolyte membrane can be improved by modifying the arrangement of the ion clusters in the electrolyte membrane, and the present invention has been achieved.

  That is, first, the present invention is an invention of a modified solid polymer electrolyte, and the first is that the ion cluster diameter constituted by the hydrophilic group and the occluded water in the solid polymer electrolyte is regular. It has the property. As a specific standard of regularity, it is preferable that the half width of the peak intensity at 2θ = 2 to 3 ° is 1 ° or less in the X-ray small angle scattering measurement. The second is characterized in that an ion cluster composed of a hydrophilic group and occluded water in the solid polymer electrolyte has orientation. As a specific measure of the orientation, the ratio of the peak intensity (D) of 2θ = 2 to 3 ° to the peak intensity (C) in the vicinity of 2θ = 0.5 ° (D / C) by X-ray small angle scattering measurement. ) Is preferably 0.3 or more. The third is X-ray small angle scattering measurement in which the ratio (C / E) of the peak intensity (C) near 2θ ≦ 0.5 ° to the peak intensity (E) at 2θ ≦ 0.5 ° is 0. .3 or more is preferable. The fourth is X-ray small angle scattering measurement, and the ratio (D / E) of the peak intensity (D) at 2θ = 2 to 3 ° to the peak intensity (E) at 2θ ≦ 0.5 ° is 0.3. The above is preferable. The fifth feature is that the ion cluster diameter constituted by the hydrophilic group and the occluded water in the solid polymer electrolyte has regularity and orientation.

  2ndly, this invention is invention of the manufacturing method of a polymer electrolyte, and controls the regularity of the ion cluster diameter comprised by the hydrophilic group and occlusion water in a solid polymer electrolyte.

Specifically, the solid polymer electrolyte is uniformly subjected to electron beam or radiation treatment, and the regularity of the ion cluster diameter constituted by the hydrophilic group and the occluded water in the solid polymer electrolyte is controlled. Here, as a step of uniformly applying electron beam or radiation treatment to the solid polymer electrolyte,
(1) The area irradiated with the electron beam or radiation is made larger than the area of the base film made of the solid polymer electrolyte (to eliminate unevenness in the amount of radical irradiation)
(2) Start the polymerization reaction within 24 hours after irradiating the raw material monomer of the solid polymer electrolyte with an electron beam or radiation (to eliminate unevenness of radical abundance due to radical deactivation)
(3) Store at 0 ° C. or lower after irradiation with electron beam or radiation (suppress radical deactivation)
It is preferably exemplified by one or more selected from.

As another specific method for controlling the regularity of the ion cluster diameter,
(4) Uniform reaction temperature (for example, surround the reaction vessel with a heat insulating material)
(5) Boil treatment (for example, boil in hydrogen peroxide solution or sulfuric acid aqueous solution for about 10 minutes)
(6) Annealing is performed (for example, after heating to 120 ° C. in a nitrogen gas atmosphere, slowly cooling)
One or more types selected from are preferably exemplified.

  3rdly, this invention is invention of the other manufacturing method of a polymer electrolyte, and provides orientation to the ion cluster comprised by the hydrophilic group and occlusion water in a solid polymer electrolyte.

Here, as a step of imparting orientation to the ion cluster composed of the hydrophilic group and the occluded water in the solid polymer electrolyte,
(7) Stretching the solid polymer electrolyte,
(8) An electric potential is applied to the solid polymer electrolyte from the outside.
(9) A solid polymer electrolyte film having uniaxial or biaxial orientation is used.
One or more types selected from are preferably exemplified.

  Fourthly, the present invention is a solid polymer electrolyte membrane comprising the above solid polymer electrolyte, and is excellent in ion conductivity.

  5thly, this invention is a fuel cell which has the said solid polymer electrolyte, and is excellent in electric power generation performance.

The concept of ion clusters used in the present invention explains proton conduction in the electrolyte membrane. The electrolyte membrane is made of, for example, a hydrocarbon-based resin or a fluorine-containing resin having a hydrophilic functional group such as a sulfonic acid group (SO ₃ ⁻ ). The main chain portion of the hydrocarbon resin or fluorine-containing resin constitutes a hydrophobic portion. Moreover, the hydrophilic group part of a side chain forms a cluster with occluded water. The clusters are connected by a narrow channel, and it is thought that protons move through these channels.

  According to the present invention, the ion cluster diameter constituted by the hydrophilic group and the occluded water in the solid polymer electrolyte has regularity, or the ion cluster has orientation, so that the ion conductivity is excellent and the machine It is possible to provide a solid polymer electrolyte having high strength. For example, when this solid polymer electrolyte is used as a solid polymer electrolyte membrane of a solid polymer fuel cell, it can be a solid polymer fuel cell operable under high temperature and low humidity conditions.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
1 and 2 show image diagrams of ion clusters in the electrolyte.

  FIG. 1A is a schematic diagram of a conventional ion cluster formed in an electrolyte membrane. Clusters having a cluster diameter B are dispersed at intervals A. As shown in FIG. 1A, both the cluster interval A and the cluster diameter B are non-uniform, and the regularity of the cluster distribution is small. For this reason, it is inferior to ion conductivity. When such a conventional ion cluster is viewed as a small angle scattering peak, the peak half-value width of 2θ = 2 to 3 ° is large.

  FIG. 1B is a schematic view of the electrolyte of the present invention in which ion clusters are formed with high regularity in the electrolyte membrane. As shown in FIG. 1B, both the cluster interval A and the cluster diameter B are uniform, and the regularity of the cluster distribution is high. For this reason, it is excellent in ion conductivity. When such an ion cluster of the present invention is subjected to X-ray small angle scattering measurement, as shown in FIG. 2, the peak half-value width of 2θ = 2 to 3 ° is small and becomes 1 ° or less. The measurement was performed at room temperature and a relative humidity of 90%.

  FIG. 3 is a schematic view of the electrolyte of the present invention in which ion clusters are formed with high orientation in the electrolyte membrane. As shown in FIG. 3, the clusters are oriented in a certain direction (Y-axis direction). For this reason, it is excellent in ion conductivity and also in strength due to orientation. Here, uniaxial orientation is performed in the Y-axis direction, but biaxial orientation is more preferable in the XY direction. When such an ion cluster of the present invention is measured by X-ray small angle scattering, as shown in FIG. 4, the peak intensity (D) of 2θ = 2 to 3 ° with respect to the peak intensity (C) in the vicinity of 2θ = 0.5 °. ) Ratio (D / C) is 0.3 or more. Similarly, the ratio (C / E) of the peak intensity (C) near 2θ ≦ 0.5 ° to the peak intensity (E) when 2θ ≦ 0.5 ° is 0.3 or more. Furthermore, the ratio (D / E) of the peak intensity (D) at 2θ = 2 to 3 ° to the peak intensity (E) at 2θ ≦ 0.5 ° is 0.3 or more. The measurement was performed at room temperature and a relative humidity of 90%.

  In addition, the conventional evaluation method for solid polymer electrolytes was to evaluate the performance of the electrolyte membrane by measuring the conductivity by the alternating current impedance method and the relaxation time by NMR. The behavior is measured indirectly, and the cluster diameter, cluster spacing, cluster distribution, etc. could not be known accurately.

  The electron beam or radiation treatment used as the radical irradiation in the treatment of the present invention irradiates the solid polymer electrolyte with an accelerated electron beam or radiation such as α rays, β rays, γ rays, and X rays. Either electron beam or radiation treatment may be applied and is not particularly limited. Preferably, electron beam treatment is preferred from the viewpoint of short treatment time. At this time, the electron dose applied to the solid polymer electrolyte is preferably 1 to 2000 kGy, more preferably 3 to 1000 kGy. In particular, the irradiation is most preferably in the range of 3 to 500 kGy.

  When the amount of electron beam irradiation is less than 1 kGy, the polymer chain is not broken and recombined, and the cluster diameter does not grow, which is not preferable because the conductivity cannot be improved. Moreover, since radicals are not sufficiently generated in the solid polymer electrolyte, the radicals cannot be reacted to sufficiently crosslink the solid polymer electrolyte, and the mechanical strength of the solid polymer electrolyte is not improved. On the other hand, when the electron dose is more than 2000 kGy, the electrolyte group in the solid polymer electrolyte is dropped and conductivity is lowered, or the structure of the solid polymer electrolyte is broken and becomes brittle.

  In addition to the above, the solid polymer electrolyte according to the present invention may be a solid polymer electrolyte obtained by impregnating a solid polymer electrolyte with a polymerizable monomer and then performing electron beam or radiation treatment.

  In this case, since the polymerizable monomer can be polymerized even at a temperature near room temperature (25 ° C.), the temperature range to which the electron beam or radiation treatment is applied is not particularly limited, and various temperature ranges are possible. Can be selected.

The solid polymer electrolyte used in the present invention refers to a polymer having an electrolyte group or a precursor thereof. Specifically, as the polymer, a fluorine-containing polymer in which the entire polymer skeleton is fluorinated, and a part of the polymer skeleton is fluorinated (for example, —CF ₂ —, —CHF—, —CFCl—). And a fluorine / hydrocarbon polymer having a bond such as a hydrocarbon polymer that does not contain fluorine in the polymer skeleton.

  More specifically, as the fluorine-containing polymer, tetrafluoroethylene polymer, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, tetrafluoroethylene-hexafluoropropylene copolymer, tetrafluoroethylene-hexafluoropropylene- Perfluoroalkyl vinyl ether copolymer, tetrafluoroethylene-trifluorostyrene copolymer, tetrafluoroethylene-trifluorostyrene-perfluoroalkyl vinyl ether copolymer, hexafluoropropylene-trifluorostyrene copolymer, hexafluoropropylene- Examples thereof include trifluorostyrene-perfluoroalkyl vinyl ether copolymers.

  Fluorine / hydrocarbon polymers include polyvinylidene fluoride, polystyrene-graft-ethylenetetrafluoroethylene copolymer, polystyrene-graft-polytetrafluoroethylene, polystyrene-graft-polyvinylidene fluoride, polystyrene-graft-hexafluoropropylene A tetrafluoroethylene copolymer, a polystyrene-graft-ethylenehexafluoropropylene copolymer, etc. are mentioned.

  Examples of the hydrocarbon polymer include polyetheretherketone, polyetherketone, polysulfone, polyethersulfone, polyimide, polyamide, polyamideimide, polyetherimide, polyphenylene, polyphenylene ether, polycarbonate, polyester, and polyacetal. In particular, those containing an aromatic group in the skeleton are preferable, and those having an aromatic group are more preferable. General-purpose resins such as polyethylene, polypropylene, polystyrene, and acrylic resins may be used.

  The electrolyte group of the solid polymer electrolyte may be any functional group capable of proton conduction, and specifically, a sulfonic acid group, a phosphonic acid group, a carboxylic acid group, and the like are preferable. In addition, the precursor of the electrolyte group may be a functional group capable of proton conduction by derivatization by chemical reaction (for example, hydrolysis). Specifically, the precursor of the sulfonic acid group, the phosphonic acid group Precursors and precursors of carboxylic acid groups are preferred. Particularly preferred are metal ions such as fluoro and sodium. The solid polymer electrolyte may contain one type of electrolyte group or precursor thereof, or may contain two or more types.

  As such a solid polymer electrolyte, a fluorine-containing electrolyte having an electrolyte group or a precursor thereof on a fluorine-containing polymer, or a fluorine-based electrolyte having an electrolyte group or its precursor on a fluorine / hydrocarbon polymer. A hydrocarbon-based electrolyte having an electrolyte group or a precursor thereof in a hydrocarbon-based polymer can be mentioned, and a fluorine-based electrolyte and a fluorine-containing electrolyte are preferable. In particular, a fluorine-containing electrolyte is preferable from the viewpoint of excellent chemical stability and durability.

  More specifically, Nafion (registered trademark, DuPont), Flemion (registered trademark, Asahi Glass Co., Ltd.), Aciplex (registered trademark, Asahi Kasei Co., Ltd.) and the like are suitable.

  The solid polymer electrolyte is preferably in the form of a membrane, but is not particularly limited, and various shapes can be selected according to the application.

  The polymerizable monomer means a radically polymerizable monomer having an electrolyte group or a precursor thereof or capable of introducing an electrolyte group later. The electrolyte group of the polymerizable monomer may be a functional group capable of proton conduction, and specifically, a sulfonic acid group, a phosphonic acid group, a carboxylic acid group, and the like are preferable.

  Specific examples of such polymerizable monomers include vinyl sulfonic acid, allyl sulfonic acid, styrene sulfonic acid, vinyl phosphonic acid, allyl phosphonic acid, styrene phosphonic acid, vinyl benzyl phosphonic acid, acrylic acid, and methacrylic acid. It is done. Moreover, you may convert into an electrolyte group by derivatization (for example, hydrolysis etc.) by a chemical reaction using these ester bodies. In addition, an electrolyte group may be introduced later by using styrene or the like by sulfonation or phosphonation.

  When the solid polymer electrolyte of the present invention is used, for example, as a solid polymer electrolyte membrane of a solid polymer fuel cell, it is superior in conductivity and mechanical strength in a high temperature and low humidity environment as compared with a conventional electrolyte membrane. Therefore, operation under high temperature and low humidity conditions is possible, and battery performance is improved.

In the following, preferred embodiments of the present invention will be described.
Example 1
A hydrocarbon-based polymer electrolyte membrane was used as the solid polymer electrolyte. And the process of said (1)-(6) was performed and the regularity of the ion cluster diameter was controlled. For comparison, an untreated hydrocarbon polymer electrolyte membrane was prepared (Comparative Example 1).

(Example 2)
A hydrocarbon polymer electrolyte membrane was used as the solid polymer electrolyte, and the treatments (7) to (9) were performed to impart orientation to the ion clusters.

Example 3
Using a hydrocarbon polymer electrolyte membrane as the solid polymer electrolyte, the treatments (1) to (6) are performed to control the regularity of the ion cluster diameter, and the treatments (7) to (9) are performed. To give orientation to the ion clusters.

The electrolyte membranes of Examples 1 to 3 and Comparative Example 1 were subjected to small angle X-ray diffraction measurement when containing water. Further, the conductivity was determined by the following formula in an aqueous solution of H ₂ SO ₄ at room temperature and direct current.
σ = L / R · A
Where σ: conductivity (S / cm)
L: Distance between electrodes R: Resistance (Ω)
A: The cross-sectional area (cm ² ) conductivity of the film was examined.

  The results of the small angle X-ray diffraction measurement are shown in FIG. The conductivity measurement results are shown in FIG. From the result of FIG. 2, it can be seen that the peak half-value width of 2θ = 2 to 3 ° is small and is 1 ° or less. From the results of FIG. 5, it can be seen that the conductivity of the hydrocarbon polymer electrolyte membrane subjected to the treatment of the present invention is improved as compared with the untreated hydrocarbon polymer electrolyte membrane.

Example 4
As the solid polymer electrolyte, Nafion (trade name) which is a fluorine-containing polymer electrolyte membrane was used. And the process of said (1)-(5) was performed and the regularity of the ion cluster diameter was controlled. For comparison, untreated Nafion was prepared (Comparative Example 2).

(Example 5)
Nafion was used as the solid polymer electrolyte, and the treatments (6) to (8) were performed to impart orientation to the ion clusters.

(Example 6)
Using Nafion as the solid polymer electrolyte, the treatments (1) to (5) are performed to control the regularity of the ion cluster diameter, and the treatments (6) to (8) are performed to form the ion clusters. Orientation was imparted.

The electrolyte membranes of Examples 4 to 6 and Comparative Example 2 were subjected to small angle X-ray diffraction measurement when containing water. Further, the membrane resistance of each electrolyte membrane was measured with a direct current in H ₂ SO ₄ aq at room temperature, and the conductivity was determined by the above formula.

  The results of the small angle X-ray diffraction measurement are shown in FIG. The conductivity measurement results are shown in FIG. From the result of FIG. 4, the ratio (D / C) of the peak intensity (D) at 2θ = 2 to 3 ° to the peak intensity (C) near 2θ = 0.5 ° is 0.3 or more. I understand. Further, the ratio (C / E) of the peak intensity (C) in the vicinity of 2θ ≦ 0.5 ° to the peak intensity (E) at 2θ ≦ 0.5 ° is 0.3 or more, and 2θ It can be seen that the ratio (D / E) of the peak intensity (D) at 2θ = 2 to 3 ° to the peak intensity (E) at ≦ 0.5 ° is 0.3 or more. From the result of FIG. 6, it can be seen that the conductivity of the Nafion subjected to the treatment of the present invention is improved as compared with the untreated Nafion.

It is a schematic diagram which shows the regularity of the ion cluster in the electrolyte membrane of the past and this invention. It is a X-ray small angle scattering measurement result of the ion cluster in the electrolyte of the past and this invention. It is a schematic diagram which shows by the orientation of the ion cluster in the electrolyte membrane of this invention. It is a X-ray small angle scattering measurement result of the ion cluster in the electrolyte of the past and this invention. The conductivity measurement result of Examples 1-3 and the electrolyte membrane of the comparative example 1. FIG. The conductivity measurement result of the electrolyte membrane of Examples 4-6 and the comparative example 2. FIG.

Claims (3)

A method for producing a solid polymer electrolyte in which the half-value width of the peak intensity at 2θ = 2 to 3 ° is 1 ° or less in X-ray small angle scattering measurement, comprising a hydrophilic group in the solid polymer electrolyte and occluded water The solid polymer electrolyte is characterized in that one or more treatments selected from the following steps (1) to (5) are applied to the solid polymer electrolyte so that the ion cluster diameter is regular : Manufacturing method .
(1) A step of irradiating a solid polymer electrolyte with an electron beam or radiation, wherein the irradiation area is larger than a base film area made of the solid polymer electrolyte,
(2) A step of starting a polymerization reaction within 24 hours after irradiating the raw material monomer of the solid polymer electrolyte with an electron beam or radiation,
(3) A step of storing the solid polymer electrolyte at 0 ° C. or lower after irradiation with an electron beam or radiation,
(4) a step of boiling the solid polymer electrolyte, and
(5) A step of annealing the solid polymer electrolyte. Whether the ratio (D / C) of the peak intensity (D) at 2θ = 2 to 3 ° to the peak intensity (C) near 2θ = 0.5 ° is 0.3 or more in the X-ray small angle scattering measurement The ratio (C / E) of the peak intensity (C) around 2θ = 0.5 ° to the peak intensity (E) at 2θ ≦ 0.5 ° is 0.3 or more, or 2θ ≦ 0 A method for producing a solid polymer electrolyte in which the ratio (D / E) of peak intensity (D) at 2θ = 2 to 3 ° to peak intensity (E) at 5 ° is 0.3 or more, One or more treatments selected from the following steps (6) to (8) for the solid polymer electrolyte so that the ion cluster composed of the hydrophilic group and the occluded water in the polymer electrolyte has orientation : A method for producing a solid polymer electrolyte, comprising :
(6) a step of stretching the solid polymer electrolyte;
(7) applying a potential from the outside to the solid polymer electrolyte; and
(8) A step of using a solid polymer electrolyte film having uniaxial or biaxial orientation. In X-ray small angle scattering measurement, the half width of the peak intensity at 2θ = 2 to 3 ° is 1 ° or less, and the ion cluster diameter constituted by the hydrophilic group and the occluded water in the solid polymer electrolyte has regularity. In addition, in the X-ray small angle scattering measurement, the ratio (D / C) of the peak intensity (D) at 2θ = 2 to 3 ° to the peak intensity (C) near 2θ = 0.5 ° is 0.3 or more. Or the ratio (C / E) of the peak intensity (C) near 2θ = 0.5 ° to the peak intensity (E) at 2θ ≦ 0.5 ° is 0.3 or more, or 2θ The ratio (D / E) of the peak intensity (D) at 2θ = 2 to 3 ° to the peak intensity (E) at ≦ 0.5 ° is 0.3 or more, and the ion cluster diameter has orientation. Thus, with respect to the solid polymer electrolyte, one or more selected from the following steps (1) to (5) and the following (6) to (8) The process for producing a solid polyelectrolyte, characterized in that applying one or more processing selected from process.
(1) A step of irradiating a solid polymer electrolyte with an electron beam or radiation, wherein the irradiation area is larger than a base film area made of the solid polymer electrolyte,
(2) A step of starting a polymerization reaction within 24 hours after irradiating the raw material monomer of the solid polymer electrolyte with an electron beam or radiation,
(3) A step of storing the solid polymer electrolyte at 0 ° C. or lower after irradiation with an electron beam or radiation,
(4) a step of boiling the solid polymer electrolyte, and
(5) A step of annealing the solid polymer electrolyte.
(6) a step of stretching the solid polymer electrolyte;
(7) applying a potential from the outside to the solid polymer electrolyte; and
(8) A step of using a solid polymer electrolyte film having uniaxial or biaxial orientation.

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