JP2023097850A - Resin composition and battery - Google Patents

Abstract

To provide a resin composition that can be suitably used for forming a resin layer to be interposed between an electrolyte layer containing concrete and an electrode and can achieve long-term stabilization of a power supply, and to provide a battery that can be easily manufactured by using the resin composition and is excellent in terms of long-term stability of the power supply.SOLUTION: A resin composition is used for forming a resin layer of a battery in which an electrolyte layer containing concrete, and a first electrode and a second electrode are arranged via at least the resin layer, and contains resin having an acidic group or its salt and a polyhydric alcohol. The battery is constituted by arranging the electrolyte layer containing the concrete, the first electrode, and the second electrode through the resin layer formed by using the resin composition.SELECTED DRAWING: Figure 1

Description

An embodiment of the present invention relates to a resin composition, and more particularly, a resin composition that can be suitably used for forming a resin layer interposed between an electrolyte layer and an electrode in a concrete battery using concrete as an electrolyte layer. Regarding. Another embodiment of the present invention relates to a concrete battery using the resin composition of the above embodiment.

Accurately grasping the state of infrastructure structures such as expressways and tunnels is very important from the viewpoint of maintenance and management of structures. Therefore, in order to enable efficient maintenance and maintenance management, attempts have been made to install sensors in infrastructure structures for constant remote monitoring. However, in order to build a monitoring system using sensors, it is essential to develop an energy harvesting device that enables long-term sensor operation. Therefore, the development of concrete batteries and sensors that use concrete, which is the main material of infrastructure structures, as an electrolyte layer is attracting attention. Above all, expectations are rising for concrete batteries that enable power supply from infrastructure structures.

In concrete batteries and sensors, electrodes are provided on the surface of the concrete that constitutes the structure, and thus various methods of attaching the electrodes to the surface of the concrete have conventionally been investigated. For example, Patent Literature 1 discloses an electrode sheet consisting of a conductive hot-melt layer. In Patent Literature 1, a conductive hot-melt layer is composed of a thermoplastic resin and a conductive filler, and such a conductive hot-melt layer is adhered firmly to a structure by thermocompression bonding. Then, it is disclosed that an electric signal obtained from the structure can be acquired through the bonded conductive hot-melt layer, and can be driven as a corrosion sensor.

However, in order to fabricate the sensor disclosed in Patent Document 1, a special tool for attaching the conductive hot-melt layer to the structure is required, which lacks convenience. Moreover, in order to produce a conductive hot-melt layer, it is necessary to heat and stir the hot-melt resin and the conductive filler at a temperature of 130° C. or higher for several hours. Therefore, the manufacturing cost tends to be high. In addition, since the conductive hot-melt layer is strongly adhered to the structure, it is expected that the removability will be poor and the disposal cost will be high.

JP 2020-064037 A JP 2020-113379 A

On the other hand, Patent Literature 2 discloses a concrete device in which a concrete electrolyte layer and electrodes are bonded together using hydrogel. According to such a method, a device can be produced only by laminating the hydrogel on the electrolyte layer and attaching the electrodes. Therefore, according to the above method, the device can be manufactured more easily than the method using the conductive hot-melt layer. Moreover, in the example of Patent Document 2, it is described that the current flows stably over approximately 7,000 hours.

However, in the concrete battery disclosed in Patent Document 2, the voltage fluctuates greatly, and improvement is desired from the viewpoint of long-term stability of power supply. Further, there is room for further study on the composition of hydrogel, and the development of a resin composition that can be suitably used to form a resin layer interposed between the electrolyte layer of concrete and the electrode is desired.

Therefore, in view of the above situation, the present invention provides a resin composition that can be suitably used to form a resin layer interposed between an electrolyte layer containing concrete and an electrode, and that can realize long-term stabilization of power supply. I will provide a. The present invention also provides a battery that can be easily produced using the above resin composition and has excellent long-term stability of power supply.

As a result of intensive studies to solve the above problems, the present inventors have found that a resin composition containing a resin containing an acidic group or a salt thereof can provide high voltage and power, and can solve the above problems. I have completed my invention. That is, embodiments of the invention include the following.

One embodiment of the present invention is a resin composition for forming the resin layer of a battery in which an electrolyte layer containing concrete and a first electrode and a second electrode are arranged at least through the resin layer. The present invention relates to a resin composition containing a resin having an acidic group or a salt thereof and a polyhydric alcohol.

In one embodiment, the acidic group is preferably at least one selected from the group consisting of a carboxyl group, a sulfonic acid group, and a phosphoric acid group.

In one embodiment, the content of the polyhydric alcohol is preferably 30 to 90% by mass based on the total mass of the resin composition.

In one embodiment, the resin having an acidic group or a salt thereof preferably contains structural units derived from at least one selected from the group consisting of (meth)acrylic acid and (meth)acrylic acid salts.

In one embodiment, the resin composition preferably further contains an electrolyte. The content of the electrolyte is preferably 10% by mass or less based on the total mass of the resin composition.

Another embodiment of the present invention is a battery in which an electrolyte layer containing concrete, and a first electrode and a second electrode are arranged with at least a resin layer interposed therebetween, wherein the resin layer is the It relates to a battery formed from a resin composition.

In one embodiment, the resin layer includes a first resin layer and a second resin layer,
The first electrode is arranged on one surface of the electrolyte layer with at least the first resin layer interposed therebetween,
The second electrode is preferably arranged on the other surface of the electrolyte layer with at least the second resin layer interposed therebetween.

In one embodiment, the first electrode and the second electrode are preferably arranged on the same surface of the electrolyte layer with at least the resin layer interposed therebetween.

According to the present invention, it is possible to provide a resin composition that can be suitably used to form a resin layer interposed between an electrolyte layer containing concrete and an electrode, and that can realize long-term stabilization of power supply. . In addition, by using the above resin composition, it is possible to provide a battery that can be easily produced and has excellent long-term stability of power supply.

FIG. 1 is a schematic cross-sectional view showing a structural example of a battery that is one embodiment of the present invention. FIG. 2 is a schematic cross-sectional view showing a structural example of a battery that is one embodiment of the present invention. FIG. 3 is a schematic cross-sectional view showing a structural example of a battery that is one embodiment of the present invention. FIG. 4 is a schematic cross-sectional view showing a structural example of a battery that is one embodiment of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail. However, the present invention is not limited to the embodiments described below, and various modifications are possible without departing from the scope of the present invention.

<1> Resin Composition One embodiment of the present invention relates to a resin composition containing a resin having an acidic group or a salt thereof and a polyhydric alcohol. This resin composition forms the resin layer of the battery in which an electrolyte layer containing concrete (hereinafter also referred to as a concrete layer) and the first electrode and the second electrode are arranged at least through the resin layer. can be suitably used for Various components constituting the resin composition will be described in more detail below.

(Resins having acidic groups or salts thereof)
A "resin having an acidic group or a salt thereof" means a resin having a structural unit derived from a monomer having a structure of an acidic group or a salt thereof (hereinafter also referred to as an ionic monomer). The above resin may be a resin prepared using at least the above ionic monomer, or may be a resin obtained by using a nonionic monomer in combination as necessary.

When a pair of electrodes is composed of a combination of elements having different work functions, it is considered that the current and voltage flowing through the electrolyte layer are substantially determined according to the difference in work function between the electrodes. On the other hand, in the embodiment of the present invention, a resin having ion conductivity such as an acidic group or a salt thereof is used as a resin composition for forming a resin layer interposed between an electrolyte layer containing concrete and an electrode. Characterized by constructing things. According to the above embodiment, it is possible to increase the output value of the battery with the resin having ion conductivity. Although not bound by theory, the resin constituting the resin layer has a structure of an acidic group or a salt thereof, so that these structural sites are adsorbed to the electrode surface to change the work function of the electrode, resulting in As a result, it is believed that the difference in work function between the electrodes increases and the output of the battery increases.

The acidic group in the resin may be at least one selected from the group consisting of a carboxyl group, a sulfonic acid group and a phosphoric acid group. Salts of acidic groups may be either inorganic salts or organic salts obtained by substituting hydrogen atoms in carboxyl groups, sulfonic acid groups, and phosphoric acid groups with inorganic or organic substances. For example, specific examples of inorganic salts include sodium, lithium, magnesium, potassium, and calcium salts. Specific examples of organic salts include ammonium salts, pyridinium salts, guanidinium salts, imidazolium salts, phosphonium salts, and sulfonium salts. The series of organic salts is not particularly limited. For example, the ammonium salt can be any of primary, secondary, tertiary and quaternary ammonium salts.

In one embodiment, the resin preferably contains at least a resin having a structure of a carboxyl group or a salt thereof (hereinafter also referred to as a carboxyl group-containing polymer). Specific examples of carboxyl group-containing polymers include synthetic polymers such as (meth)acrylic acid homopolymers and copolymers or salts thereof, hyaluronic acid, xanthan gum, gellan gum, pectin, carrageenan, alginic acid, polysaccharides such as karaya gum and carboxymethylcellulose. , as well as proteins such as glycinin (soybean protein). A carboxyl group-containing polymer can be used individually by 1 type or in combination of 2 or more types.

The carboxyl group-containing polymer may be either a non-crosslinked polymer or a crosslinked polymer, and may be used in combination as appropriate. A non-crosslinked polymer is a polymer obtained from monofunctional monomers. A crosslinked polymer is a polymer obtained from a monomer group containing a polyfunctional monomer and having a crosslinked structure.

In one embodiment, the weight average molecular weight of the non-crosslinked carboxyl group-containing polymer is preferably 20,000 or more, more preferably 150,000 or more. On the other hand, the upper limit of the weight-average molecular weight is not particularly limited, but may be approximately 5,000,000 or less. By using a non-crosslinked carboxyl group-containing polymer having a weight average molecular weight of 20,000 or more, it is possible to easily obtain the gel strength necessary for forming a sheet.

Among the carboxyl group-containing polymers, polyacrylic acid and salts thereof can be preferably used. (Meth)acrylic acid and its salts can be used to prepare polyacrylic acid and its salts. The salt of (meth)acrylic acid may be an inorganic salt or an organic salt. To prepare salts of polyacrylic acid, for example, sodium (meth)acrylate, ammonium (meth)acrylate, potassium (meth)acrylate, calcium (meth)acrylate, and magnesium (meth)acrylate At least one selected from the group can be used.

In one embodiment, the resin having an acidic group or a salt thereof preferably contains at least one of polyacrylic acid and a salt thereof, more preferably at least polyacrylic acid. From this point of view, the resin uses at least (meth)acrylic acid as an ionic monomer, and if necessary, an inorganic salt of (meth)acrylic acid and / or It is more preferred to include resins that are derived using organic salts.

Therefore, in one embodiment, the resin may include a resin having structural units derived from (meth)acrylic acid. In another embodiment, the resin may include a resin having structural units derived from (meth)acrylic acid and structural units derived from sodium acrylate and/or ammonium acrylate. In the resin of such an embodiment, the ratio of structural units derived from at least one selected from the group consisting of (meth)acrylic acid and (meth)acrylic acid is the total monomers used as raw materials. Based on the mass, the content is preferably 30% by mass or more, more preferably 35% by mass or more, and even more preferably 40% by mass or more.

In one embodiment, 3-[[2-(acryloyloxy)ethyl]dimethylammonio]propane-1-sulfonic acid (SPDA) and 2-acryloyloxyethyl acid phosphate (PAEE) as ionic monomers can also be used. These may be used in combination with at least one of (meth)acrylic acid and (meth)acrylic acid salts. In one embodiment, it is preferable to use SPDA or PAEE and (meth)acrylic acid in combination.

In one embodiment, in addition to the ionic monomer, if necessary, a nonionic monomer may be used in combination to prepare the resin having the acidic group or salt thereof.
Specific examples of nonionic monomers that can be used include alkyl (meth)acrylates such as methyl (meth)acrylate. The number of carbon atoms in the alkyl group may be 1-20, preferably 1-12.

Other examples of nonionic monomers include mono- or dialkyl(meth)acrylamides such as (meth)acrylamide, N-isopropyl(meth)acrylamide, N,N-dimethyl(meth)acrylamide, N-hydroxyethyl Hydroxyalkyl (meth)acrylamide such as (meth)acrylamide, hydroxyalkyl (meth)acrylate such as 2-hydroxyethyl (meth)acrylate, polyalkylene glycol such as polyethylene glycol (meth)acrylate, polypropylene glycol (meth)acrylate (Meth)acrylate and the like.

Still other examples include nonionic polyfunctional monomers such as polyethylene glycol diacrylate and polyalkenylarenes such as divinylbenzene. In one embodiment, the use of nonionic polyfunctional monomers is preferred because it improves crosslinkability.

When a nonionic polymer is used in combination, the resin is composed of a structural unit (ionic structural unit) having an acidic group derived from an ionic monomer or a structure of a salt thereof, and a structure derived from a nonionic monomer. unit (nonionic structural unit). From the viewpoint of sufficiently obtaining the effects of the present invention, the proportion of structural units derived from nonionic monomers in the resin is 70% by mass or less based on the total mass of the monomers used as raw materials. , more preferably 65% by mass or less, and even more preferably 60% by mass or less.

In one embodiment, the resin uses a monofunctional ionic monomer containing (meth)acrylic acid and/or a salt thereof and a nonionic monomer containing a nonionic polyfunctional monomer. It is preferably a resin formed by In such an embodiment, the content of the nonionic polyfunctional monomer is preferably 0.01 to 5% by mass based on the total mass of the monomers used to constitute the resin. , more preferably 0.05 to 4% by mass, more preferably 0.1 to 3% by mass.

The above resin having an acidic group or a salt thereof can be prepared by using at least an ionic monomer and by a known method. For example, it can be produced by thermally polymerizing an ionic monomer containing at least (meth)acrylic acid and its salt at a temperature of about 40 to 130° C. using a thermal polymerization initiator. It can also be prepared by irradiating with active energy rays for polymerization. When the active energy ray is light, a photopolymerization initiator may be used as necessary. Furthermore, it can also be manufactured by using both thermal polymerization and active energy ray polymerization.

Specific examples of usable thermal polymerization initiators include, but are not limited to, azo compounds such as 2,2'-azobisisobutyronitrile, and organic peroxides such as benzoyl peroxide. Specific examples of usable photopolymerization initiators include acetophenones such as α-hydroxyacetophenone, benzoins such as benzoin isobutyl ether, and acylphosphine oxides such as bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide. etc. The amount of the polymerization initiator used is preferably 0.1 to 20% by mass, more preferably 0.5 to 15% by mass, based on the total mass of the monomers used as resin raw materials. well, more preferably 1 to 10% by mass.

In one embodiment, the production of the resin may be performed prior to mixing with other components constituting the resin composition such as a polyhydric alcohol described later, or when mixed with the other components (i.e., the resin composition during the preparation of) may be carried out together.
From the viewpoint of simplification of the production process of the resin composition, it is preferable to carry out the production of the resin together with the preparation of the resin composition. In this case, the resin composition is prepared by mixing a resin raw material, a polymerization initiator, a polyhydric alcohol, and optionally an electrolyte and water at a temperature of, for example, 40 to 130°C. can do.

In one embodiment, a commercially available resin can also be used as the resin having an acidic group or a salt thereof. For example, sodium alginate (FUJIFILM Wako Pure Chemical Industries, Ltd., product name "sodium alginate 300-400") and carboxymethylcellulose sodium (FUJIFILM Wako Pure Chemical Industries, Ltd., product name "carboxymethylcellulose sodium") can also be used. can.

The content of the resin having an acidic group or a salt thereof is preferably 1 to 50% by mass, more preferably 3 to 40% by mass, more preferably 5 to 30% by mass, based on the total mass of the resin composition. % by mass is more preferred. In one embodiment, the content of the resin containing structural units derived from (meth)acrylic acid and/or a salt of acrylic acid is even more preferably within the above range. When the content of the resin is adjusted within the above range, the electrical conductivity is improved, and the output from the battery can be easily increased when the resin layer is formed. Moreover, the flexibility of the resin layer can be maintained, and good adhesion to the electrode and the electrolyte layer can be easily obtained.

(polyhydric alcohol)
"Polyhydric alcohol" means a compound having two or more hydroxyl groups in the molecule. The number of hydroxyl groups in the polyhydric alcohol may be from 2 to 12, preferably 2 or 3.
Specific examples of polyhydric alcohols include ethylene glycol, propylene glycol, butadiene glycol, glycerin, pentaerythritol, polyethylene glycol, polypropylene glycol, polyglycerin, polyoxyethylene polyglyceryl ether, polyoxypropylene polyglyceryl ether, and sorbitol. One of these may be used alone, or two or more may be used in combination. In one embodiment, the polyhydric alcohol preferably contains at least one selected from the group consisting of glycerin, ethylene glycol, propylene glycol, polyglycerin, polyethylene glycol, and polypropylene glycol, and more preferably contains at least glycerin. preferable.

In one embodiment, the content of the polyhydric alcohol may be 30 to 90% by weight based on the total weight of the resin composition. The content of the polyhydric alcohol is preferably 40 to 90% by mass, more preferably 50 to 90% by mass. When the content of the polyhydric alcohol in the resin composition is adjusted within the above range, the electrical conductivity is improved, and the output from the battery can be easily increased when the resin layer is formed. Moreover, the flexibility of the resin layer can be maintained, and good adhesion to the electrode and the electrolyte layer can be easily obtained.

In one embodiment, the resin composition may further contain water in addition to the above resin and polyhydric alcohol. By adjusting the water content in the resin composition, the resin composition can be prepared in various forms. For example, when water is contained, it becomes easy to obtain the resin composition in the form of gel.

In one embodiment, the resin composition may further contain a cross-linking agent. For example, inorganic compounds that generate polyvalent metal cations such as aluminum chloride, zirconium chloride, magnesium chloride, and calcium chloride as cross-linking agents that ionically bond with carboxyl group-containing polymers, and 1,3-diaminoethane, 4, Organic compounds that generate polyvalent cations, such as 4′-diaminodiphenylmethane, and melamine. A crosslinking agent can be used individually by 1 type or in combination of 2 or more types. In one embodiment, the aluminum salt alum can be suitably used as a cross-linking agent for the carboxyl group-containing polymer.

Cross-linking agents can be added in any amount. For example, it is preferable to use 0.1 to 50 parts by mass of the cross-linking agent with respect to 100 parts by mass of the carboxyl group-containing polymer. More preferably, the ratio is 0.5 to 50 parts by mass. When the ratio of the amount of the cross-linking agent added is adjusted to 0.1 part by mass or more, gelation tends to proceed rapidly as the moisture content decreases. Moreover, when the ratio of the amount of the cross-linking agent to be added is adjusted to 50 parts by mass or less, a gel-like sheet with high transparency and excellent appearance can be easily produced.

In addition, when the resin composition contains a resin containing a structural unit derived from (meth)acrylic acid and/or a salt thereof, the resin composition tends to have excellent adhesiveness. Therefore, the resin composition can also be used as an adhesive. When the resin composition is used as an adhesive, the content of water in the resin composition is preferably 1% by mass or less based on the total mass of the resin composition. In addition, when the resin composition is used in the form of an adhesive, components such as a tackifier, a surface conditioner, an adhesion-imparting agent, and an antioxidant may be added as necessary in the preparation of the resin composition. good too.

In one embodiment, the resin composition may further contain an electrolyte as necessary from the viewpoint of enhancing ion conductivity. Electrolytes used to form the resin composition include metal salts such as alkali metal salts and alkaline earth metal salts, and onium salts such as ammonium salts. Among these, alkali metal salts, alkaline earth metal salts and ammonium salts are preferred, alkali metal salts and alkaline earth metal salts are more preferred, and alkali metal salts are even more preferred.

Specific examples of alkali metal salts include chloride salts such as sodium chloride, lithium chloride and potassium chloride; carbonates such as sodium carbonate, lithium carbonate and potassium carbonate; and nitrates such as sodium nitrate, lithium nitrate and potassium nitrate. Specific examples of alkaline earth metal salts include chloride salts such as magnesium chloride and calcium chloride, carbonates such as magnesium carbonate and calcium carbonate, and nitrates such as magnesium nitrate and calcium nitrate. Specific examples of ammonium salts include chloride salts such as ammonium chloride and tetramethylammonium chloride.

Although not particularly limited, in one embodiment, at least one selected from the group consisting of lithium chloride, sodium chloride, potassium chloride, and ammonium chloride can be preferably used. Based on the total weight of the resin composition, the content of the electrolyte may be 0.1% by weight or more. The electrolyte content is preferably 10% by mass or less, more preferably 7% by mass or less, and even more preferably 3% by mass or less. In one embodiment, the electrolyte content is preferably 0.1 to 10% by mass, more preferably 0.5 to 5% by mass, and still more preferably 0.8 to 3% by mass. %.

<2> Battery Another embodiment of the present invention relates to a battery having an electrolyte layer containing concrete, a resin layer formed from the resin composition of the above embodiment, and an electrode (hereinafter also referred to as a concrete battery). In the concrete battery of the above embodiment, an electrolyte layer containing concrete, and a first electrode and a second electrode are arranged with at least a resin layer interposed therebetween. The configuration of the concrete battery will be described in more detail below.

<Electrolyte layer>
The electrolyte layer is mainly composed of concrete (hereinafter also referred to as concrete layer). Concrete means concrete in a broad sense, which is also called cement concrete, and may be either a concrete component containing coarse aggregate or a mortar component not containing coarse aggregate. It is known that concrete can function as an electrolyte because it generally contains ionic compounds such as calcium chloride and magnesium chloride. In the present invention, the concrete layer used as the electrolyte layer is not limited to a specific composition, and may have the composition of concrete generally envisioned in the art. For example, concrete can be prepared in accordance with JISR5201 using mortar sand ISO671 test standard sand. The shape of the electrolyte layer is not particularly limited, and can be seen in shapes such as cubes and rectangular parallelepipeds consisting of only plane surfaces, shapes with curved surfaces such as tubular shapes and tunnel shapes, and structures such as other buildings. It may have a complex shape such as

<Electrode>
The electrodes are not particularly limited, and may be electrodes made of materials known in the art. The first electrode and the second electrode are composed of a combination of materials suitable for the anode and cathode, ie materials such as metals having different work functions. Metal foils such as gold, silver, copper, platinum, zinc, lead, aluminum, iron, palladium, tin, magnesium, nickel, chromium, and alloys thereof can be used as materials for the electrodes. In one embodiment, the first electrode can be constructed from zinc foil and the second electrode can be constructed from copper foil.

An electrode is provided on the surface of the electrolyte layer via at least a resin layer formed using the resin composition of the above embodiment. 1 to 4 are schematic cross-sectional views showing structural examples of a concrete battery that is one embodiment of the present invention.

As shown in FIGS. 1-3, in one embodiment, the first electrode 3a is arranged on one side 2a of an electrolyte layer (concrete layer) 2 comprising at least a resin layer 1 interposed therebetween. On the other hand, the second electrode 3b may be arranged on the other surface 2b of the electrolyte layer 2 with at least the resin layer 1 interposed therebetween.
In the above embodiment, the first electrode 3a and the second electrode 3b may be arranged so as to face each other with the electrolyte layer 2 and the resin layer 1 interposed therebetween. In this case, the first electrode 3a and the second electrode 3b may be formed so as to cover the entire surface of the electrolyte layer 2 on which they are arranged, at least through the resin layer 1 (FIG. 1). Also, the first electrode 3a and the second electrode 3b may be formed so as to cover at least part of the surface of the electrolyte layer 2 on which they are arranged, with the resin layer 1 interposed therebetween. As a modification of the above embodiment, as shown in FIG. 3, the first electrode 3a and the second electrode 3b may be arranged so as not to face each other.

As another embodiment, as shown in FIG. 4, the first electrode 3a and the second electrode 3b are arranged on the same surface of the electrolyte layer 2 with at least the resin layer 1 interposed therebetween with a distance therebetween. good too.

<Resin layer>
In the concrete battery of the above embodiment, at least a resin layer formed using the resin composition of the above embodiment is provided between the electrolyte layer (concrete layer) and the electrode. The resin layer not only has ionic conductivity, but also adhesiveness. Therefore, the adhesion between the electrolyte layer and the electrode can be enhanced, and the electrode can be easily maintained on the surface of the electrolyte layer. The resin layer may be formed as a single layer, or may be formed as a multi-layer structure of two or more layers. When forming the resin layer as a multilayer structure, the composition of the resin composition may be adjusted so that each layer has a different composition. In one embodiment, in the structure of the concrete battery, a layer such as a support layer such as a non-woven fabric or a primer layer may be added between the electrolyte layer and the electrode as long as the effect of the resin layer is not reduced. For example, when a layer such as a primer is added, the adhesion between the resin layer, the electrolyte layer, and the resin layer can be further enhanced.

The concrete battery of the above-described embodiment includes a resin layer formed from the resin composition of the above-described embodiment on at least a part of one surface of the electrolyte layer, and an electrode disposed on the resin layer. It can be produced by a method. Alternatively, an electrode with a resin layer is provided in advance by providing a resin layer formed from the resin composition of the above embodiment on the electrode, and then at least part of one surface of the electrolyte layer is coated with the resin layer. A method of attaching electrodes can also be applied.

The resin composition which is one embodiment of the present invention can also be used in the form of a gel-like sheet having tackiness. Therefore, even after the electrodes are arranged and fixed, it is easy to peel off the electrodes and re-arrange the electrodes as necessary. Moreover, since the concrete battery of the above embodiment can output a high voltage, it is possible to supply stable power over a long period of time. Concrete structures such as buildings include steel frames and the like. Therefore, in one embodiment, a battery can also be configured by using a steel frame as an internal electrode and providing an electrode on the surface of a concrete structure via a resin layer formed from the resin composition of the above embodiment. .

EXAMPLES Hereinafter, the present invention will be described specifically and in detail with reference to examples, but these examples are merely one aspect of the present invention, and the present invention is not limited by these examples. In the table, "wt%" means "% by weight".

<Preparation of concrete>
The concrete used in the production examples and various tests described below was prepared using mortar sand ISO671 standard sand for testing, and was prepared according to JISR5201 unless otherwise specified. Concrete and concrete specimens described below refer to concrete prepared as described above.

<1> Preparation of Resin Raw Material A resin raw material (resin precursor) used in Examples was prepared as follows.
(Resin raw material (A-1))
In a sample bottle, 95 parts of acrylic acid as an ionic monomer and 5 parts of PEG600# diacrylate as a polyfunctional monomer were added and stirred to obtain a resin raw material (A-1).

(Resin raw materials (A-2) to (A-8))
In the same manner as for resin raw material (A-1), each component was blended and stirred according to the composition shown in Table 1 to obtain resin raw materials (A-2) to (A-8).

Resin raw materials (resin precursors) used in Comparative Examples were prepared as follows (resin raw materials (B-1), (B-2)).
In the same manner as the resin raw material (A-1), each component was blended and stirred according to the composition shown in Table 1 to obtain resin raw materials (B-1) and (B-2).

The details of the abbreviations described in the table are as follows.
SPDA: 3-[[2-(acryloyloxy)ethyl]dimethylammonio]propane-1-sulfonic acid (manufactured by Tokyo Chemical Industry Co., Ltd.)
PAEE: 2-acryloyloxyethyl acid phosphate (manufactured by Kyoeisha Chemical Co., Ltd., product name “Light acrylate P-1A (N)”)
PEG600# diacrylate: (manufactured by Kyoeisha Chemical Co., Ltd., product name “Light Acrylate 14EG-A”)

<2> Resin composition (Example 1)
Each component shown in Table 2 was put into a sample bottle to prepare a resin composition. More specifically, in a sample bottle, 50 parts of the previously prepared resin raw material (A-1), 9.9 parts of ion-exchanged water, 30 parts of glycerin as a polyhydric alcohol, and Omnirad 1173 (α-hydroxyacetophenone , manufactured by IGM Resins) and 10 parts of sodium chloride as an electrolyte were added.
Next, each of the resin compositions obtained in Examples and Comparative Examples was coated on the release-treated PET film so as to have a thickness of 1 mm to obtain a coating layer. Next, the coating layer was irradiated with ultraviolet rays of 2000 mJ/cm ² using a metal halide lamp to cure the coating layer, thereby obtaining a gel-like sheet made of the resin composition.

(Examples 2 to 9)
Resin compositions 2 to 9 were prepared in the same manner as in Example 1 by blending each component in the amounts shown in Table 2. Furthermore, in the same manner as in Example 1, gel-like sheets composed of the above resin compositions 2 to 9 were obtained.

(Examples 10 and 11)
A resin and glycerin as a polyhydric alcohol were blended in a sample bottle in the amounts shown in Table 2 and stirred (coating liquid A). Next, water and sodium chloride as an electrolyte were added to another sample bottle in the amounts shown in Table 2 and stirred (coating solution B). After mixing and stirring the obtained coating liquid A and coating liquid B, a gel sheet composed of the resin compositions 10 and 11 was immediately coated on a release-treated PET film so as to have a thickness of 1 mm. obtained respectively.

(Comparative Examples 1 and 2)
Each component was put into a sample bottle in the amount shown in Table 3 to obtain a resin composition. More specifically, the sample bottle contains resin raw materials (B-1, B-2) shown in Table 1, an initiator (Omnirad 1173), water, a polyhydric alcohol (glycerin), and an electrolyte (sodium chloride). was put in. These components were then stirred at 25° C. for 30 minutes to obtain resin compositions 1 and 2 for comparison.
Next, in the same manner as in Example 1, gel-like sheets composed of Comparative Resin Compositions 1 and 2 were obtained.

<Evaluation of Adhesion>
Each gel-like sheet made of the resin composition obtained in Examples and Comparative Examples was cut into a size of 20 mm in width×40 mm in length, and then attached to a copper foil of 25 mm in width×60 mm in length×0.1 mm in thickness. rice field.
Next, the PET film on the gel-like sheet was peeled off, and a concrete test piece whose surface had been ground with a grinder was attached to the peeled surface. The concrete test pieces are made of concrete prepared in accordance with JISR5201 using mortar sand ISO671 test standard sand.
The adhesion is measured by using a tensile tester EZ-SX manufactured by Shimadzu Corporation to measure the load value when the edge of the copper foil is grasped and peeled off at an angle of 90 degrees at a speed of 50 mm / min. It was evaluated according to the following criteria. Table 2 shows the results.
(Evaluation criteria for adhesion)
○: load 3N or more (good)
×: load less than 3N (defective)

<3> Concrete battery (production of concrete battery)
Two cut pieces were prepared by cutting the gel-like sheets previously prepared in Examples and Comparative Examples into a width of 10 mm and a length of 10 mm. One of the cut gel sheets was attached to a zinc plate of width 10 mm×length 30 mm×thickness 0.5 mm. Another gel-like sheet was attached to a copper plate of width 10 mm×length 30 mm×thickness 0.5 mm. Thus, a sheet-attached electrode made of the resin composition was produced.
Next, the peelable PET film on each gel-like sheet was peeled off, and the sheet side of the sheet-attached electrode was bonded to the main surface of concrete molded into a 10 mm square so as to face each other. That is, a concrete battery having a structure of electrode (zinc plate)/resin composition (gel sheet)/concrete/resin composition (gel sheet)/electrode (copper plate) was produced.

<Evaluation of initial voltage>
Immediately after the concrete battery was produced as described above, the voltage between the copper plate and the zinc plate was measured using a source meter ("SOURCE METER 2400" manufactured by KEITHLEY). The initial voltage was evaluated from the measured values according to the following criteria. Table 2 shows the results.
(Evaluation criteria for initial voltage)
◎: 0.95 V or more (extremely good)
○: 0.85 V or more and less than 0.94 V (good)
△: 0.70 V or more and less than 0.85 V (within use range)
×: less than 0.70 V (defective)

<Evaluation of initial power>
The concrete battery whose initial voltage was evaluated was connected to a source meter ("SOURCE METER 2400" by KEITHLEY) so that the positive electrode was a copper plate and the negative electrode was a zinc plate, and IV characteristics were measured. From the obtained data, the current value×voltage value was calculated, and the maximum value was defined as the initial power and evaluated according to the following criteria. Table 2 shows the results.
(Evaluation criteria for initial power)
◎: 1 μW or more (very good)
○: 0.5 μW or more and less than 1 μW (good)
△: 0.1 μW or more and less than 0.5 μW (within use range)
×: less than 0.1 μW (defective)

<Evaluation of voltage over time>
The concrete battery for which the initial voltage was evaluated was left in an environment of 25° C. and 50% humidity for 4 weeks, and the copper plate-zinc plate was measured using a source meter (KEITHLEY “SOURCE METER 2400”) in the same manner as the initial voltage evaluation. was measured and evaluated according to the following criteria. Table 2 shows the results.
(Evaluation criteria for voltage over time)
◎: 0.95 V or more (extremely good)
○: 0.85 V or more and less than 0.94 V (good)
△: 0.70 V or more and less than 0.85 V (within use range)
×: less than 0.70 V (defective)

<Evaluation of power over time>
The concrete battery for which the initial power was evaluated was left for 4 weeks in an environment with a temperature of 25° C. and a humidity of 50%. Table 2 shows the results.
(Evaluation criteria for power over time)
◎: 1 μW or more (very good)
○: 0.5 μW or more and less than 1 μW (good)
△: 0.1 μW or more and less than 0.5 μW (within use range)
×: less than 0.1 μW (defective)

The details of the abbreviations described in the table are as follows.
ALGNa: sodium alginate 300-400 (manufactured by FUJIFILM Wako Pure Chemical Industries, Ltd.)
CMCNa: carboxymethylcellulose sodium (manufactured by FUJIFILM Wako Pure Chemical Industries, Ltd.)
PEG: polyethylene glycol 400 (manufactured by FUJIFILM Wako Pure Chemical Industries, Ltd.)
Polyglycerin-10: Polyglycerin decamer (manufactured by Sakamoto Pharmaceutical Co., Ltd.)
Omnirad 1173: α-hydroxyacetophenone (manufactured by IGM Resins)

As can be seen in Tables 2 and 3, the resin compositions (Examples) that are embodiments of the present invention have excellent adhesion to concrete test pieces and electrode materials such as copper foil. In addition, the resin composition can be used in the form of a gel sheet, and when applied to a concrete battery, it is found to be excellent in voltage, power, voltage over time, and power over time.
On the other hand, in Comparative Example 1, the resin raw material did not contain an ionic monomer, and in Comparative Example 2, the resin composition did not contain a polyhydric alcohol. This is because the ionic components flowed into the concrete layer because the resin raw material does not contain an ionic monomer, and because the resin composition does not contain a polyhydric alcohol, the water retention is poor and the aging of the resin composition is poor. It is presumed that this is due to the deterioration in the

From the above, it can be seen that, according to the present invention, a combination of a specific resin and a polyhydric alcohol can realize a resin composition that has tackiness and adhesiveness and can function well as an electrolyte. In addition, when an electrolyte layer containing concrete and an electrode are arranged via a resin layer formed from such a resin composition, the adhesion between the electrolyte layer and the electrode is enhanced, and the long-term stability of power supply is excellent. It can be seen that a concrete battery can be realized.

1 resin layer 2 electrolyte layer (concrete layer)
2a, 2b one face of the electrolyte layer 3a first electrode 3b second electrode 10 battery

Claims (8)

A resin composition for forming the resin layer of a battery in which an electrolyte layer containing concrete and a first electrode and a second electrode are disposed at least through the resin layer, the resin composition comprising an acidic group or a salt thereof and a polyhydric alcohol. 2. The resin composition according to claim 1, wherein said acidic group is at least one selected from the group consisting of carboxyl group, sulfonic acid group and phosphoric acid group. 3. The resin composition according to claim 1, wherein the content of said polyhydric alcohol is 30 to 90% by mass based on the total mass of the resin composition. Any one of claims 1 to 3, wherein the resin having an acidic group or a salt thereof comprises a structural unit derived from at least one selected from the group consisting of (meth)acrylic acid and (meth)acrylic acid salts. 1. The resin composition according to item 1. The resin composition according to any one of claims 1 to 4, further comprising an electrolyte, wherein the content of said electrolyte is 10% by mass or less based on the total mass of the resin composition. A battery in which an electrolyte layer containing concrete and a first electrode and a second electrode are arranged with at least a resin layer interposed therebetween, wherein the resin layer is the resin layer according to any one of claims 1 to 5. A battery formed from a resin composition. The resin layer includes a first resin layer and a second resin layer,
The first electrode is arranged on one surface of the electrolyte layer with at least the first resin layer interposed therebetween,
7. The battery according to claim 6, wherein said second electrode is arranged on the other surface of said electrolyte layer with at least said second resin layer interposed therebetween. 7. The battery according to claim 6, wherein said first electrode and said second electrode are arranged on the same surface of said electrolyte layer with at least said resin layer interposed therebetween.

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