JP6324783B2 - Battery electrode and battery - Google Patents

Description

The present invention relates to a battery electrode and a battery.

In recent years, the importance of development and improvement of batteries has been increasing in many industries from portable devices to automobiles mainly in terms of performance and secondary battery.

Batteries, especially storage batteries composed of negative electrodes containing lead species, zinc species, and cadmium species, undergo a dissolution and precipitation reaction of metals in the vicinity of the electrode active material layer, etc., when charging and discharging are repeated for a long period of time. However, there has been a problem that the shape of the electrode active material such as shape change or dendrite is changed, resulting in capacity deterioration and shortening of life. In order to solve such a problem, a technique of using a gel electrolyte or adding a polymer to an electrode composition has been reported so far (see, for example, Patent Document 1).

By the way, a separator electrode integrated power storage member is disclosed as an electrode constituent member using a porous member (for example, see Patent Document 2). Moreover, the porous solid zinc electrode and its manufacturing method are disclosed (for example, refer patent document 3).

International Publication No. 2013/027767 JP 2006-236647 A Special table 2008-518408

As in the case of the specific storage battery described above, when the dissolution / precipitation reaction of the active material occurs along with the battery reaction, it is extremely important to control the form of precipitation of the active material. In particular, in nickel / zinc batteries and nickel / cadmium batteries, if the deposit form of the negative electrode active material zinc species or cadmium species in the negative electrode is not controlled, the shape change proceeds with each charge / discharge reaction, and the negative electrode active A phenomenon occurs in which material is depleted and hydrogen is generated. This is one of the important issues in battery development.

The invention described in Patent Document 1 can exert an effect of suppressing shape change and dendrite in the case where the active material that has been an anion is precipitated again in the vicinity of the electrode during charging. It was not considered to prevent the precipitation in the supersaturated state except in the vicinity of the electrode in the battery. In Patent Documents 2 and 3, the problem of shape change is not described, and there is room for improvement to sufficiently solve the problem. Further, when the invention described in Patent Document 2 is applied to a zinc negative electrode, dendrites derived from zinc species are generated and grown in the porous separator layer, which may impair battery performance. Therefore, when charging and discharging are repeated over a long period of time, convection of the electrolyte occurs accidentally depending on the battery shape, and there is room for study to suppress electrode shape change that may occur depending on the convection.

Such a problem is particularly important in a battery using a zinc negative electrode or a cadmium negative electrode, but has a battery using other electrodes.
A battery using a zinc negative electrode composed of a zinc species has been studied for a long time with the spread of the battery, and the safety of the alkaline aqueous solution and the electrode without using a rare metal as an active material. Although it has a solid superiority in terms of element strategy that it can be formed, it has not been the mainstream of battery development in recent years due to the above-mentioned problems. If the above-mentioned problems are solved, there is a possibility that the battery that can achieve both safety / advantage and performance can be used extremely favorably in many industries from portable devices to automobiles.

The present invention has been made in view of the above-described situation, and is a zinc negative electrode or other electrode. When a battery is constructed, the shape change and dendrite of the electrode can be sufficiently controlled, and the life can be extended. An object of the present invention is to provide a battery electrode capable of suppressing hydrogen generation and a battery.

The present inventors first focused on a battery using a zinc negative electrode having safety and superiority as described above, and in order to prevent the shape change of the zinc negative electrode, an active material (an zincate ion) that was an anion (zinc acid ion) at the time of discharge ( Various mechanisms for controlling the reprecipitation of zinc oxide in the vicinity of the negative electrode were investigated. As a result of intensive studies, the present inventors have found that the electrode has a structure composed of an electrically insulating material in and / or on the active material layer. In such a battery, the structure is physically controlled to prevent the ions from detaching from the active material layer, or the ions are supersaturated near the electrode, and the active material is reprecipitated near the electrode. As a result, it has been found that the effect of suppressing the electrode shape change can be remarkably exhibited. Thereby, ions are not depleted in the vicinity of the electrode, and the active material can be retained abundantly on the electrode, so that hydrogen generation can be suppressed. Furthermore, the present inventors have also found that a short circuit between electrodes due to dendrites is physically suppressed by the structure, and the battery can have a long life. And, the present inventors can control the electrode shape change and dendrite sufficiently if the negative electrode and the positive electrode other than the zinc negative electrode also have the above structure, and can prolong the service life. The present inventors have found that hydrogen generation can be suppressed and have arrived at the present invention.

That is, the present invention is a battery electrode including a current collector and an active material layer containing active material particles, and the electrode is electrically insulating in and / or on the active material layer. The structure is an electrode for a battery having a structure that inhibits detachment of ions derived from the active material particles from the active material layer.
Moreover, this invention is also a battery provided with the electrode for batteries of this invention, and electrolyte.

The present invention is described in detail below.
In addition, the form which combined two or more each preferable form of this invention described below is also a preferable form of this invention.

<Battery electrode of the present invention>
The battery electrode of the present invention may be a negative electrode or a positive electrode, but is preferably a negative electrode.
The battery electrode of the present invention has a structure composed of an electrically insulating material in and / or on the active material layer. Below, the structure which the battery electrode of this invention has is demonstrated.

〔Structure〕
As the structure in the battery electrode of the present invention, the detachment of ions derived from the active material particles from the active material layer is inhibited, or the ions become supersaturated inside the voids of the structure and reprecipitate. As long as it can be controlled in this way, various structures can be mentioned. Note that the structure is on the active material layer that the structure may be on the current collector side when viewed from the active material layer side, or on the opposite side of the current collector when viewed from the active material layer side. Good.
The structure is preferably at least partially overlapped with the active material layer when viewed from the current collector side, but more preferably overlapped with the entire active material layer. When the structure is in the active material layer with respect to the overlapped portion, the ions derived from the active material particles are prevented from going straight from the current collector side toward the electrode surface, and thereby the ions are active material Detachment from the layer can be inhibited. In addition, when the structure is on the active material layer and is on the current collector side when viewed from the active material layer side, the ions are supersaturated inside the voids of the structure and the active material is inside the structure. In this way, the active material enters the structure and the structure layer becomes part or all of the active material layer, so that the structure is in the active material layer. Similarly, it is possible to inhibit the ions derived from the active material particles precipitated inside the structure from going straight from the current collector side toward the electrode surface. Further, when the structure is on the active material layer and on the side opposite to the current collector as viewed from the active material layer side, it may directly inhibit the ions derived from the active material particles from leaving the active material layer. it can. As a result, the ions derived from the active material particles are not depleted in the vicinity of the electrode, the active material can be retained abundantly on the electrode, the electrode shape change can be suppressed, and the effects of the present invention for suppressing hydrogen generation can be exhibited remarkably. . Moreover, the short circuit between electrodes by dendrite can be physically suppressed by the said structure.

In the battery electrode of the present invention, it is preferable that the structure has a gap through which the ions can pass. Thereby, in a battery provided with the battery electrode of this invention, it becomes possible to perform a battery reaction suitably, exhibiting the effect of this invention.

In the battery electrode according to the present invention, it is more preferable that the structure retain at least a part of the ions in the void. Retaining the ions in the gap means that the ions may move in the gap as long as the ions remain in the gap. This facilitates reprecipitation of the active material in the vicinity of the electrode. As the void portion, a granular hole is more preferable. The granular hole may have a concave shape in which the surface of the structure is partially recessed near the surface of the structure. Further, they may be in communication with each other. If the gap is a granular hole, it is considered that at least a part of the ions convect in the gap. In the present specification, convection means flowing around or recirculating.
In addition, the inhibition, retention, and convection of the detachment of ions mean those in the process of causing the battery reaction of the battery including the battery electrode of the present invention.

Examples of the structure having voids through which ions can pass include, for example, (1) those having a structure in which voids are randomly connected, (2) those formed by entwining a plurality of fibers, and (3) through holes. It is preferable that a plurality of sheets each having a gap are overlapped so that the positions of the holes do not overlap, and the gaps are regularly communicated with each other. Each of these structures may be disposed in the active material layer or may be disposed on the active material layer. Moreover, the structure may be a combination of two or more of the above (1) to (3).

In said (1), it is one preferable form of this invention that the said space | gap part is a granular hole formed by removing the granular material surrounded, for example by the electrically insulating material. As described later, the structure may be formed by, for example, kneading an electrically insulating polymer and a granular material, applying and drying, and then eluting at least a part of the granular material. it can.

The particulate matter may be any material that can form pores in the resulting structure by being removed from the electrically insulating material. For example, the particulate matter is selected from Group 1 to Group 15 of the periodic table. It is possible to use one containing at least one metal element.
Further, when the structure is in the active material layer, a part of the granular material is removed, and the void formed by removing the granular material becomes the void of the structure according to the present invention, and the other remaining It is preferable that the granular material functions as an active material. In this case, it is preferable to use the same granular material as the active material described later. For example, when the structure is used for a zinc negative electrode, the granular material is preferably zinc oxide. The shape of the granular material, preferred average particle diameter, specific surface area, aspect ratio, these measurement methods, the blending ratio to the composition for forming the structure, respectively, the preferred shape of the active material, the average particle diameter, It is the same as the specific surface area, aspect ratio, these measuring methods, and the compounding ratio in the battery electrode composition. Thus, the composition for forming the structure may also serve as the battery electrode composition. Among the compositions for forming the structure, those capable of forming the active material layer and the structure in the active material layer are also referred to as electrode compositions capable of forming the structure in the active material layer in this specification. . In addition, when forming an electrode using the electrode composition which can form the structure in an active material layer, it is not necessary to use the electrode composition for forming an active material layer separately.

Further, in the above (1), the structure is porous or foamable, and the pores or bubbles communicate with each other to form a void portion is also one preferred form of the present invention.

In (2) above, an electrically insulating material constitutes the fiber. A plurality of fibers are intertwined and usually form a network structure. Note that the plurality of fibers may be the same material or different materials. In the above (2), the structure composed of the electrically insulating material is particularly preferably a porous body, and more preferably a porous nonwoven fabric.
When the region where the fiber and the active material layer overlap is viewed from above, the area where the active material layer is exposed from the network structure portion of the fiber is 70% or less with respect to 100% of the region. It is preferable that More preferably, it is 30% or less, more preferably 10% or less, and particularly preferably 5% or less. Most preferably, the active material layer is not substantially exposed from the network structure portion of the fiber.

The length of the fiber is preferably 10 μm or more, for example. More preferably, it is 100 μm or more. Moreover, it is preferable that it is 100 mm or less. More preferably, it is 10 mm or less.
Moreover, it is preferable that the diameter of the said fiber is 0.1 micrometer or more, for example. More preferably, it is 1 μm or more. Moreover, it is preferable that it is 1000 micrometers or less. More preferably, it is 500 μm or less.

In the above (3), as the sheet having the through hole, an electrically insulating material formed into a sheet shape as necessary can be used. For example, polytetrafluoroethylene, polyethylene, polypropylene, etc. Is more preferable.
Note that the positions of the holes do not overlap as long as the circumference of one hole and the circumference of the other hole do not completely match when the sheet main surface is viewed in plan view. A part and a part of the other hole may overlap each other, or one hole may be completely included in the other hole. Preferably, a part of one hole and a part of the other hole overlap each other.

The structure in the present invention is made of an electrically insulating material. Examples of the electrically insulating material include an electrically insulating polymer.
The polymer may be either thermoplastic or thermosetting, and includes a hydrocarbon moiety-containing polymer such as polyolefin, an aromatic group-containing polymer such as polystyrene; an ether group-containing polymer such as alkylene glycol; a polyvinyl alcohol, etc. Hydroxyl group-containing polymers; Amide bond-containing polymers such as polyamide and polyacrylamide; Imide group-containing polymers such as polymaleimide; Carboxyl group-containing polymers such as poly (meth) acrylic acid; Carboxylic acid groups such as poly (meth) acrylates Polymer; sulfonate moiety-containing polymer; quaternary ammonium salt or quaternary phosphonium salt-containing polymer; ion-exchange polymer; natural rubber; artificial rubber such as styrene-butadiene rubber (SBR); hydroxyalkyl cellulose (for example, hydroxy Ethyl cell Amino group-containing polymers such as polyethyleneimine; over scan), sugars such as carboxymethyl cellulose and polyurethane. Among them, the polymer is selected from the group consisting of an aromatic group, a carboxyl group, a carboxylate group, a hydroxyl group, an amino group, an ether group, an amide bond (—CO—NH—), and a urethane group (—NHCOO). It is preferable to contain at least one kind or to be a hydrocarbon. The carboxylate base is preferably a lithium carboxylate base, a sodium carboxylate base, or a potassium carboxylate base. More preferably, it is a sodium carboxylate base. Examples of the hydrocarbon include polyolefin. Above all, the polymer is (i) an insulator, (ii) excellent in physical strength, (iii) removing particulate matter surrounded by an electrically insulating material as described later. In the case of forming a void, it is preferable to select appropriately considering comprehensively the three points that the particulate matter is not bound and is easy to separate the particulate matter. Containing polymer, aromatic group containing polymer, ether group containing polymer, amide bond containing polymer, carboxyl group containing polymer, carboxylate group containing polymer, sulfonate moiety containing polymer, quaternary ammonium salt or quaternary phosphonium salt containing polymer Saccharides and polyurethanes are preferred. More preferred are hydrocarbons, amide bond-containing polymers, and polyurethanes. As the hydrocarbon, polyolefin is more preferable. As the polyurethane, foamable polyurethane is more preferable.
Note that the polymer may be in a fiberized state by heat, pressure, or the like. The strength and the like of the structure can be adjusted by polymerizing the polymer.

The above polymers are radical (co) polymerization, anion (co) polymerization, cation (co) polymerization, graft (co) polymerization, living (co) polymerization, dispersion (co) polymerization, emulsification from monomers corresponding to the structural unit. Obtained by (co) polymerization, suspension (co) polymerization, ring-opening (co) polymerization, cyclization (co) polymerization, polymerization by irradiation with light, ultraviolet rays or electron beams, metathesis (co) polymerization, electrolytic (co) polymerization, etc. be able to. When these polymers have a functional group, they may be present in the main chain and / or side chain, and may exist as a binding site with a crosslinking agent. These polymers may be used alone or in combination of two or more.
The polymer may be crosslinked with an organic crosslinking agent compound. However, when the crosslinked polymer has water absorption, the structure may be cracked. Therefore, the crosslinked polymer should not have water absorption.

The polymer preferably has a weight average molecular weight of 200 to 7000000. Thereby, the ion conductivity, viscosity, flexibility, strength, and the like of the anion conductive material can be adjusted. The weight average molecular weight is more preferably 400 to 6500000, and still more preferably 500 to 5000000.
The weight average molecular weight can be measured by gel permeation chromatography (GPC).

The battery electrode of the present invention includes an active material layer. The structure described above may be included in the active material layer, and the structure may be separately disposed on the active material layer.
The battery electrode of the present invention may further contain a polymer, a conductive additive, and other components in addition to the active material particles in the active material layer. Below, the active material particle | grains, binder, conductive support agent, and other component which are contained in the active material layer of the battery electrode of this invention are demonstrated in order.

[Active material particles]
The active material particles contained in the active material layer of the battery electrode of the present invention may be a positive electrode active material or a negative electrode active material, but a negative electrode active material is preferred.

When the battery electrode of the present invention is a negative electrode, the negative electrode active material includes carbon species, lithium species, sodium species, magnesium species, cadmium species, lead species, zinc species, tin species, silicon-containing materials, hydrogen A material normally used as a negative electrode active material of a battery, such as a storage alloy material or a noble metal material such as platinum, can be used. Among these, the active material in the battery electrode of the present invention preferably contains a zinc species. Thereby, the effect of the present invention which suppresses shape change and dendrite becomes remarkable. Here, the zinc species refers to a zinc-containing compound. The zinc species may be repeatedly oxidized and reduced by driving the battery as long as it contains zinc.

The zinc-containing compound is not particularly limited as long as it can be used as an active material. For example, zinc oxide (1 type / 2 types / 3 types specified in JIS K 1410 (2006)), zinc hydroxide and sulfide Zinc, tetrahydroxyzinc alkali metal salt, tetrahydroxyzinc alkaline earth metal salt, zinc halide, zinc carboxylate compound, zinc alloy, zinc solid solution, zinc borate, zinc phosphate, zinc hydrogen phosphate, zinc silicate, Zinc (alloy having at least one element selected from the group consisting of elements belonging to Group 1 to Group 17 of the periodic table represented by zinc aluminate, carbonate compound, hydrogen carbonate compound, nitrate compound, sulfate compound, etc. ) Compounds, organic zinc compounds, zinc compound salts and the like. Among these, zinc oxide (1 type / 2 types / 3 types specified in JIS K 1410 (2006)), zinc hydroxide, tetrahydroxyzinc alkali metal salt, tetrahydroxyzinc alkaline earth metal salt, zinc halogen compound , Zinc carboxylate compound, zinc alloy, zinc solid solution, zinc borate, zinc phosphate, zinc silicate, zinc aluminate, zinc carbonate, selected from the group consisting of elements belonging to groups 1 to 17 of the periodic table More preferred is a zinc (alloy) compound having at least one element. The zinc alloy may be a zinc alloy used in an (alkali) dry battery or an air battery. The zinc-containing compound can be used alone or in combination of two or more.

When the battery electrode of the present invention is a positive electrode, as the positive electrode active material, those normally used as the positive electrode active material of a primary battery or a secondary battery can be used. For example, nickel-containing compounds such as nickel oxyhydroxide, nickel hydroxide and cobalt-containing nickel hydroxide; manganese-containing compounds such as manganese dioxide; silver oxide; lithium-containing compounds such as lithium cobaltate; iron-containing compounds; Is mentioned.

Examples of the shape of the active material particles include fine powder, powder, granule, granule, scale, polyhedron, rod, and curved surface. The active material particles may be not only primary particles but also secondary particles in which primary particles are aggregated.

In the battery electrode of the present invention, when a water-containing electrolytic solution is used when a storage battery is produced using the battery electrode, the decomposition reaction of water may proceed in the process of using the battery. In order to suppress this, a specific element may be introduced into the active material. Specific elements include Al, B, Ba, Bi, Br, C, Ca, Cd, Ce, Cl, Cu, Eu, F, Ga, Hg, In, La, Mg, Mn, N, Nb, Nd, Ni, P, Pb, S, Sb, Sc, Si, Sm, Sn, Sr, Ti, Tl, Y, Zr, etc. are mentioned.
Here, introducing a specific element into an active material means that the active material is a compound having these elements as constituent elements.

The average particle diameter of the active material particles is preferably 5 nm or more. More preferably, it is 10 nm or more, More preferably, it is 50 nm or more, More preferably, it is 200 nm or more, Especially preferably, it is 500 nm or more. Moreover, it is preferable that the said average particle diameter is 500 micrometers or less. More preferably, it is 100 micrometers, More preferably, it is 60 micrometers or less, More preferably, it is 10 micrometers or less, Most preferably, it is 3 micrometers or less.
The average particle diameter can be measured using a particle size distribution measuring device.

The specific surface area of the active material particles is preferably 0.1 m ² / g or more. More preferably, it is 1 m ² / g or more. Moreover, it is preferable that it is 1500 m < ² > / g or less. More preferably, it is 1200 m < ² > / g or less, More preferably, it is 900 m < ² > / g or less, More preferably, it is 250 m < ² > / g or less, Most preferably, it is 50 m < ² > / g or less.
By setting the specific surface area of the active material particles within the above range, there is an effect that the shape change of the active material and the formation of passive state can be suppressed in the process of using the battery.
The specific surface area can be measured by a specific surface area measuring apparatus or the like by a nitrogen adsorption BET method.
The particles having a specific surface area as described above can be produced, for example, by making the particles into nanoparticles or by making the particle surface uneven by selecting the preparation conditions for particle production. is there.

The active material particles preferably have an aspect ratio (vertical / horizontal) of 1.1 or more. The aspect ratio (vertical / horizontal) is more preferably 2 or more, and further preferably 3 or more. The aspect ratio (vertical / horizontal) is preferably 100,000 or less. The aspect ratio (vertical / horizontal) is more preferably 50000 or less.
The aspect ratio (vertical / horizontal) can be determined from, for example, the shape of particles observed by SEM. For example, when the particles of the compound are in the shape of a rectangular parallelepiped, the longest side can be obtained by dividing the vertical length by the horizontal length, with the longest side being vertical and the second longest side being horizontal. In the case of other shapes, a point is placed in the two-dimensional shape that is created when one part is placed on the bottom so that the aspect ratio is maximized and projected from the direction that maximizes the aspect ratio. Is measured by measuring the length of one point farthest from the vertical axis and dividing the vertical length by the horizontal length with the longest side as the vertical, the longest side of the straight line passing through the vertical center point as the horizontal. be able to.
The particles of the compound having an aspect ratio (vertical / horizontal) in the above-described range may be prepared, for example, by selecting a particle having such an aspect ratio or by optimizing the preparation conditions at the stage of manufacturing the particle. It can be obtained by a method of selectively obtaining particles.

The mixing ratio of the active material in the active material layer is preferably 40 to 99.9% by mass with respect to 100% by mass of the active material layer other than the structure. When the amount of the active material is in such a range, better battery performance is exhibited when the battery electrode of the present invention is used in a battery. More preferably, it is 60-99.5 mass%, More preferably, it is 80-99 mass%, Most preferably, it is 85-98 mass%.

[Binder]
The active material layer of the battery electrode of the present invention preferably further contains a binder.
Various known binders can be used as the binder, and halogen-containing polymers such as polyvinylidene fluoride and polytetrafluoroethylene are preferable. Among them, the binder is more preferably polytetrafluoroethylene. In addition, the said binder can be used by 1 type or 2 types or more.

The binder preferably has a weight average molecular weight of 200 to 7000000. Thereby, the ionic conductivity, viscosity, flexibility, strength, and the like of the active material layer can be adjusted. The weight average molecular weight is more preferably 400 to 6500000, and still more preferably 500 to 5000000.
The weight average molecular weight can be measured by gel permeation chromatography (GPC).

The mass ratio of the binder in the active material layer is preferably 0.1 to 60% by mass with respect to 100% by mass of the active material layer other than the structure. More preferably, it is 0.5-40 mass%, More preferably, it is 1-20 mass%, Most preferably, it is 2-15 mass%.

[Conductive aid]
The battery electrode of the present invention may contain a conductive additive together with the active material particles and the binder.
Examples of the conductive assistant include conductive carbon, conductive ceramics, zinc / zinc powder / zinc alloy / (alkali) (storage) zinc used in dry batteries and air batteries (hereinafter also referred to as metal zinc). Further, metals such as copper, brass, nickel, silver, bismuth, indium, lead, and tin can be used.

Examples of the conductive carbon include graphite such as natural graphite and artificial graphite, glassy carbon, amorphous carbon, graphitizable carbon, non-graphitizable carbon, carbon nanofoam, activated carbon, graphene, nanographene, graphene nanoribbon, fullerene, carbon black, Graphitized carbon black, ketjen black, vapor grown carbon fiber, pitch-based carbon fiber, mesocarbon microbead, carbon coated with metal, carbon coated metal, fibrous carbon, boron-containing carbon, nitrogen-containing carbon, multilayer / Single-walled carbon nanotubes, carbon nanohorns, Vulcan, acetylene black, carbon treated by introducing oxygen-containing functional groups, SiC-coated carbon, expressed by dispersion / emulsion / suspension / microsuspension polymerization, etc. Treated carbon, microcapsules carbon.

Examples of the conductive ceramic include a compound containing at least one selected from Bi, Co, Nb, and Y fired with zinc oxide.

Among the above conductive aids, graphite such as natural graphite and artificial graphite, graphitizable carbon, non-graphitizable carbon, graphene, carbon black, graphitized carbon black, ketjen black, vapor-grown carbon fiber, pitch-based carbon fiber , Mesocarbon microbeads, fibrous carbon, multi-walled / single-walled carbon nanotubes, Vulcan, acetylene black, carbon treated with hydrophilicity by introducing oxygen-containing functional groups, metallic zinc, copper, brass, nickel, silver, bismuth, indium -Metals such as lead and tin are preferred. In addition, the metal zinc may be used for an actual battery such as an alkaline (storage) battery or an air battery, or may have a surface treated with other elements or carbon, or may be alloyed. May be. It may be a solid solution. The said conductive support agent can be used by 1 type, or 2 or more types.

The metallic zinc can also act as an active material. In other words, in the process of using the battery, metallic zinc, which is a conductive additive, performs a redox reaction and functions as an active material. Similarly, in the process of using the battery, metallic zinc produced from a zinc-containing compound as an active material also functions as a conductive additive. The zinc metal and zinc-containing compound added to the battery electrode composition in the preparation stage of an electrode such as a negative electrode substantially function as an active material and a conductive additive in the process of using the battery.

In the case of using a water-containing electrolyte when producing a storage battery using this conductive auxiliary agent, there may be a case where a side reaction of water proceeds in the process of using the battery, and this side reaction is suppressed. In order to do this, a specific element may be introduced into the conductive additive. Examples of the specific element include the same elements as the specific element introduced into the active material described above. When conductive carbon is used as one of the conductive assistants, specific elements include Al, B, Ba, Bi, C, Ca, Cd, Ce, Cu, F, Ga, In, La, and Mg. Mn, N, Nb, Nd, Ni, P, Pb, S, Sb, Sc, Si, Sn, Ti, Tl, Y, Zr are preferable.
Here, the introduction of a specific element into a conductive assistant means that the conductive assistant is a compound having these elements as constituent elements.

The preferable average particle diameter of the conductive auxiliary agent particles is the same as the preferable average particle diameter of the active material particles described above.
The average particle diameter can be measured by the same method as the average particle diameter of the active material particles described above.

The preferred specific surface area of the conductive auxiliary agent is the same as the preferred specific surface area of the active material particles described above. By setting the specific surface area of the conductive additive within the above range, there is an effect that the shape change of the electrode and the formation of passive state can be suppressed in the process of using the battery.
The specific surface area can be measured by the same method as the specific surface area of the active material particles.

When the battery electrode of the present invention contains a conductive additive, the content of the conductive additive in the active material layer is 0.0001 to 100% by mass of the active material in the active material layer of the present invention. It is preferable that it is 100 mass%. When the content ratio of the conductive assistant is within such a range, better battery performance is exhibited when the battery electrode of the present invention is used in a battery. More preferably, it is 0.0005-60 mass%, More preferably, it is 0.001-40 mass%.
In addition, when using metal zinc at the time of preparation of a battery electrode composition or a zinc negative electrode, metal zinc is calculated not considering an active material but as a conductive additive. In addition, zinc metal produced in the process of battery use, such as zinc oxide or zinc hydroxide, which is a zinc-containing compound, will also function as a conductive aid in the system. Since it is not zero-valent metal zinc at the time of preparing the negative electrode, the calculation is performed assuming that it is an active material, not a conductive auxiliary agent. That is, the preferable content ratio of the active material and the conductive auxiliary agent is calculated by considering the zinc-containing compound at the time of preparing the battery electrode composition and the zinc negative electrode as the active material and the metallic zinc as the conductive auxiliary agent.

[Other ingredients]
The active material layer of the battery electrode of the present invention further includes a compound, an organic compound, and an organic compound salt having at least one element selected from the group consisting of elements belonging to Group 1 to Group 17 of the periodic table It may contain at least one selected from the group consisting of The other components are compounds different from the active material, the conductive auxiliary agent, and the binder.

When the active material layer of the battery electrode of the present invention contains the other components, the mass ratio of the other components is 0. 0% with respect to 100% by mass of the active material layer other than the structure according to the present invention. It is preferable that it is 001 mass% or more. More preferably, it is 0.01 mass% or more, More preferably, it is 0.05 mass% or more. Moreover, it is preferable that it is 30 mass% or less. More preferably, it is 20 mass% or less, More preferably, it is 10 mass% or less. The active material layer according to the present invention may not contain any other components.

The mass ratio of the structure according to the present invention and the active material layer other than the structure is preferably 1/1 to 1000. More preferably, it is 1 / 2-500, More preferably, it is 1-5-200, Most preferably, it is 1-10-80.

The battery electrode of the present invention further includes a current collector.
Current collectors used for constituting the battery electrode of the present invention include (electrolytic) copper foil, copper mesh (expanded metal), copper alloy such as foamed copper, punched copper, brass, brass foil, brass mesh (expanded) Metal), foamed brass, punched brass, nickel foil, corrosion resistant nickel, nickel mesh (expanded metal), punched nickel, metal zinc, corrosion resistant metal zinc, zinc foil, zinc mesh (expanded metal), (punched) steel sheet, conductive Non-woven fabric: Ni / Zn / Sn / Pb / Hg / Bi / In / Tl / Brass (electrolytic) copper foil / copper mesh (expanded metal) / foamed copper / punched copper / brass and other copper alloys / Brass foil, brass mesh (expanded metal), foamed brass, punched brass, nickel foil, corrosion-resistant nickel, nickel Mesh (expanded metal), punched nickel, metallic zinc, corrosion-resistant metal zinc, zinc foil, zinc mesh (expanded metal), (punched) steel sheet, non-woven fabric; Ni, Zn, Sn, Pb, Hg, Bi, In, Tl, brass (Electrolytic) copper foil, copper mesh (expanded metal), foamed copper, punched copper, copper alloys such as brass, brass foil, brass mesh (expanded metal), foamed brass, punched brass, nickel foil, corrosion resistance Nickel, nickel mesh (expanded metal), punched nickel, metal zinc, corrosion-resistant metal zinc, zinc foil, zinc mesh (expanded metal), (punched) steel sheet, non-woven fabric, silver, alkaline (storage) battery, and air zinc battery Examples include materials used as bodies and containers.

The thickness of the battery electrode of the present invention is preferably 1 nm or more and 10,000 μm or less from the viewpoint of the battery configuration, suppression of peeling of the active material from the current collector, and the like. More preferably, it is 10 nm or more, More preferably, it is 20 nm or more. More preferably, it is 1500 micrometers or less, More preferably, it is 1000 micrometers or less.
The thickness of the electrode can be measured by a micrometer, a step meter, a contour shape measuring instrument, or the like.

In addition to the above, the battery electrode of the present invention may further include a general member such as a protective member used for the electrode.

The battery electrode of the present invention is preferably obtained by the method for preparing the battery electrode of the present invention described later. Especially, it is especially preferable that it is what is obtained by the preferable method of the preparation method of the battery electrode of this invention mentioned later.

[Method for Preparing Battery Electrode of the Present Invention]
The method for preparing the battery electrode of the present invention will be described below.
The battery electrode of the present invention can be prepared by various known methods, including a method for forming an electrode active material layer and a structure in the active material layer, an electrode active material layer, Specific examples of the method for forming the structure on the active material layer will be described below.

(Method for forming an active material layer of an electrode and a structure in the active material layer)
As a method for forming the active material layer of the battery electrode of the present invention and the structure in the active material layer, for example, an electrode composition capable of forming the structure in the active material layer described above is used as a current collector. Examples include the following method of preparing by coating, pressing, bonding, piezoelectric, rolling, stretching, melting, etc., and then removing a part of the electrode active material. In addition, this method is a method for forming the structure body which the space | gap part connected at random as a structure body normally.

The electrode composition capable of forming a structure in the active material layer is a mixture of the active material particles, an electrically insulating material, and a binder, a conductive additive, and other components as necessary. Can be prepared. For mixing, a mixer, blender, kneader, bead mill, ready mill, ball mill, or the like can be used. In mixing, water, an organic solvent such as methanol, ethanol, propanol, isopropanol, butanol, hexanol, tetrahydrofuran, N-methylpyrrolidone, or a mixed solvent of water and an organic solvent may be added. Before and after mixing, an operation such as sieving the active material particles or granulation may be performed in order to make the active material particles and voids have a desired diameter. Mixing may be performed by either a wet method in which a liquid component such as water or an organic solvent is added to the solid component, or a dry method in which only the solid component is added without adding the liquid component. When mixing is performed by a wet method, after mixing, liquid components such as water and organic solvent may be removed by drying. Mixing can also be performed by combining a wet method and a dry method. During mixing, pressurization / decompression may be performed, or temperature may be applied.

By the preparation method described above, an electrode composition capable of forming a structure in the active material layer is obtained as a slurry or a paste mixture. Next, the obtained slurry or paste mixture is coated, pressure-bonded, bonded, piezoelectric, rolled, stretched, melted, etc. on the current collector so that the film thickness is as constant as possible. These may be layered or non-layered.

The slurry or paste mixture may be applied to one side of the current collector, pressure-bonded, bonded, piezoelectric, rolled, stretched, melted, etc., or coated, pressure-bonded, bonded, piezoelectrically applied to both sides and the entire surface of the current collector. , Rolling, stretching, melting, etc. It is dried at 0 to 400 ° C. during coating / crimping / adhesion / piezoelectric / rolling / stretching / melting and / or after coating / crimping / adhesion / piezoelectricity / rolling / stretching / melting. More preferably, it is 15-380 degreeC as drying temperature. Drying may be performed by vacuum drying or reduced pressure drying. The drying time is preferably 5 minutes to 48 hours. You may repeat the process of coating and drying. Moreover, it is preferable to perform a press with a roll press machine etc. by the pressure of normal pressure-20t with a roll press machine etc. after drying of the said slurry or paste mixture. The pressure for pressing is more preferably a pressure of normal pressure to 15 t. You may apply the temperature of 10-500 degreeC at the time of a press. The pressing process may be performed once or a plurality of times. When performing pressing, it improves the adhesion between active materials, active materials and binders, binders, active materials and current collectors, etc., and also improves the thickness, strength, flexibility, etc. of the structure. It is also possible to adjust.

After drying the slurry or paste mixture, at least a part of the granular material such as the active material particles surrounded by the electrically insulating material is removed, and the structure according to the present invention is formed in the active material layer. Can be formed. For example, a battery precursor comprising a current collector and an electrode precursor composed of a dried product of the slurry or paste mixture and an electrolyte is prepared, and active material particles are repeatedly charged and discharged in the battery precursor. At least a part of the particulate matter surrounded by the electrically insulating material is eluted, whereby an electrode having a structure with a void portion according to the present invention can be completed.

In the method for forming the active material layer of the electrode and the structure in the active material layer described above, the mass ratio of the active material particles is 100% by mass of the electrode composition capable of forming the structure in the active material layer. It is preferable that it is 40 mass% or more. When the amount of the active material is in such a range, better battery performance can be exhibited when the battery electrode of the present invention is used in a battery. More preferably, it is 60 mass% or more, More preferably, it is 80 mass% or more, Most preferably, it is 94 mass% or more. Moreover, it is preferable that it is 99.9 mass% or less. More preferably, it is 99.5 mass% or less, More preferably, it is 99 mass% or less, Most preferably, it is 98 mass% or less.

The mass ratio of the electrically insulating material is preferably 0.025% by mass or more with respect to 100% by mass of the electrode composition capable of forming the structure in the active material layer. More preferably, it is 0.125 mass% or more, More preferably, it is 0.25 mass% or more, Most preferably, it is 0.5 mass% or more. Moreover, it is preferable that it is 15 mass% or less. More preferably, it is 10 mass% or less, More preferably, it is 5 mass% or less, Most preferably, it is 1.5 mass% or less.

The mass ratio of the binder is preferably 0.075% by mass or more with respect to 100% by mass of the electrode composition that can form the structure in the active material layer. More preferably, it is 0.375 mass% or more, More preferably, it is 0.75 mass% or more, Most preferably, it is 1.5 mass% or more. Moreover, it is preferable that it is 45 mass% or less. More preferably, it is 30 mass% or less, More preferably, it is 15 mass% or less, Most preferably, it is 4.5 mass% or less.

(Method of forming an active material layer of an electrode and a structure on the active material layer)
As a method for forming the active material layer of the battery electrode of the present invention and the structure on the active material layer, for example, the battery electrode composition is formed on a sheet composed of a plurality of fibers such as nonwoven fabric. Prepare by coating, crimping, bonding, piezoelectric, rolling, stretching, melting, etc., and applying the above active material layer on the current collector by coating, crimping, bonding, piezoelectric, rolling, stretching, melting, etc. The method is mentioned.

The battery electrode composition used to prepare the active material layer can be prepared by mixing a binder, a conductive additive, and other components as necessary together with the active material particles. A preferable mixing method is the same as the preferable mixing method in preparing the electrode composition capable of forming the structure in the active material layer described above.

By the preparation method described above, the battery electrode composition is obtained as a slurry or a paste mixture. Next, the obtained slurry or paste mixture is coated, pressure-bonded, bonded, piezoelectric, rolled, stretched on a sheet composed of a plurality of fibers such as nonwoven fabric so that the film thickness is as constant as possible. Melting. These may be layered or non-layered.

The slurry or paste mixture may be coated, pressed, bonded, piezoelectric, rolled, stretched, melted, etc. on one side of the sheet, or coated, pressed, bonded, piezoelectric, rolled, stretched on both sides and the entire surface, It may be melted.
The thickness of the slurry or paste mixture when the slurry or paste mixture is applied to the sheet, pressure bonded, bonded, piezoelectric, rolled, stretched, melted, etc. is preferably 10 μm or more, for example, 80 μm or more. More preferably, it is 160 μm or more. The thickness of the slurry or paste mixture is preferably 1000 μm or less, more preferably 500 μm or less, and further preferably 300 μm or less.
The thickness of the sheet when the slurry or paste mixture is applied to the sheet, pressure bonded, bonded, piezoelectric, rolled, stretched, melted, etc. is preferably 5 μm or more, and more preferably 40 μm or more. Preferably, it is 80 μm or more. Further, the thickness of the sheet is preferably 500 μm or less, more preferably 250 μm or less, and further preferably 150 μm or less.
By setting the thickness of the slurry or paste mixture and the thickness of the sheet within the above ranges, the effects of the present invention can be suitably obtained.

Further, the surface of the slurry or paste mixture on which the sheet is not attached may be applied to the current collector, pressure bonded, bonded, piezoelectric, rolled, stretched, melted, or the like. In this case, preferable temperature conditions, pressure conditions, and the like are those in the case where the active material layer and the structure in the active material layer are formed using the electrode composition capable of forming the structure in the active material layer described above. It is the same as that of preferable conditions. Moreover, you may make the surface where the said sheet | seat of the said slurry or paste mixture was affixed with a collector with the physical stress at the time of assembling a battery.

After drying the slurry or paste mixture, the battery electrode according to the present invention can be formed. In addition, once a battery including a current collector, a dried product of a slurry or a paste mixture, an electrode made of a sheet, and an electrolytic solution is prepared, and charging and discharging are repeated in the battery, the active material in the active material layer It can be controlled that the ions derived from the particles are supersaturated in the voids of the sheet and the active material is reprecipitated inside the sheet. In addition, the active material enters the sheet and the sheet layer becomes a part or all of the active material layer, so that ions derived from the active material particles precipitated inside the structure are directed from the collector side toward the electrode surface. It is possible to prevent the vehicle from going straight, and the effect of the present invention can be suitably obtained.
In addition, when the active material particles are introduced into the sheet in this way, the sheet has a function of an active material layer. Therefore, this is also referred to as an “active material layer” in the present specification.

In the above-described method for forming the electrode active material layer and the structure on the active material layer, the mass ratio of the active material particles is determined by the battery electrode composition 100 used to prepare the active material layer. It is preferable that it is 70 mass% or more with respect to mass%. When the amount of the active material is in such a range, better battery performance can be exhibited when the battery electrode of the present invention is used in a battery. More preferably, it is 80 mass% or more, More preferably, it is 90 mass% or more, Most preferably, it is 94 mass% or more. Moreover, it is preferable that it is 99.9 mass% or less. More preferably, it is 99.5 mass% or less, More preferably, it is 99 mass% or less, Most preferably, it is 98 mass% or less.

The mass ratio of the binder is preferably 0.1% by mass or more with respect to 100% by mass of the battery electrode composition used for preparing the active material layer. More preferably, it is 0.5 mass% or more, More preferably, it is 1 mass% or more, Most preferably, it is 2 mass% or more. Moreover, it is preferable that it is 30 mass% or less. More preferably, it is 20 mass% or less, More preferably, it is 10 mass% or less, Most preferably, it is 6 mass% or less.

The battery electrode of the present invention is not only used as a negative electrode of a battery using zinc as a negative electrode, but also a positive electrode of the battery, an alkaline metal negative battery such as lithium metal, and an alkaline earth metal negative battery such as magnesium metal. , Aluminum metal negative battery, lithium ion battery, sodium ion battery, magnesium ion battery, calcium ion battery, aluminum ion battery, nickel / hydrogen battery, nickel / metal hydride battery, nickel / cadmium battery, lithium / air battery, etc. It can be used as a positive electrode and / or a negative electrode in a battery or a fuel cell.

<Battery of the present invention>
This invention is also a battery provided with the electrode for batteries of this invention, and electrolyte.
The battery of the present invention includes a primary battery; a chargeable / dischargeable secondary battery (storage battery); use of mechanical charge (mechanical replacement of electrodes); a third electrode separate from the positive electrode and the negative electrode (for example, Any form such as utilization of an electrode for removing oxygen and hydrogen generated during charging and discharging may be used, but a secondary battery (storage battery) is preferable.

The battery of this invention is comprised using the battery electrode of this invention as a positive electrode and / or a negative electrode. Especially, it is preferable that the battery of this invention is comprised using the electrode for batteries of this invention in the negative electrode at least.
In the case where the battery electrode of the present invention is a negative electrode, the positive electrode described above is an active material that can be used for the positive electrode when the battery of the present invention is a positive electrode. A thing can be used suitably.
Further, in the case where the battery electrode of the present invention is a negative electrode, in a battery configured using the negative electrode, oxygen is used as the positive electrode active material. Perovskite type compounds that can oxidize, cobalt containing compounds, iron containing compounds, copper containing compounds, manganese containing compounds, vanadium containing compounds, nickel containing compounds, iridium containing compounds, platinum containing compounds, palladium containing compounds, gold containing compounds, silver It is also possible to use an air electrode composed of a containing compound, a carbon-containing compound, or the like.
Among these, oxygen, a manganese-containing compound, and a nickel-containing compound are preferable. That is, the positive electrode is preferably a nickel electrode, a manganese electrode, or an air electrode. More preferably, it is a nickel electrode.

In the battery of the present invention, when a separator is used, a general separator represented by the description of International Publication No. 2013/027767 can be used as the separator.
The separator can be used singly or in combination of two or more, and any number can be used as long as the resistance increases and the battery performance does not deteriorate, but only one is preferred. In the battery of the present invention, an inexpensive nonwoven fabric made of a single layer that can be easily produced with a small number of steps can be suitably used as the separator. That is, in the battery of the present invention, it is one preferable form to use a nonwoven fabric as a battery separator.

In the battery of the present invention, when an electrolytic solution is used, the electrolytic solution may be any one that is usually used as a battery electrolytic solution, and is described in paragraph numbers [0056] to [0059] of International Publication No. 2013/027767. An electrolytic solution can be used. Note that the electrolytic solution may or may not be circulated.
Further, instead of the electrolytic solution, a solid electrolyte (gel electrolyte) may be sandwiched between the negative electrode and the positive electrode.

The battery of the present invention can be used as the above-described various batteries in which the battery electrode of the present invention can be used. However, the alkaline aqueous solution-containing electrolysis is particularly resistant to the alkaline electrolyte. Batteries that use liquids, such as nickel / zinc (storage) batteries, manganese / zinc (storage) batteries, silver / zinc (storage) batteries, zinc ion (storage) batteries, nickel / cadmium (storage) batteries, nickel / hydrogen It can be suitably used as an electrode for (storage) battery, fuel cell, air (storage) battery and the like. Among them, it is particularly preferable to use as a nickel / zinc (storage) battery in which a shape change is likely to occur because the effect of the present invention becomes remarkable. Moreover, it is also possible to use with respect to the battery which uses electrolyte solutions other than alkaline aqueous solution containing electrolyte solution, for example, a lead acid battery. In addition, when it uses as a lead acid battery, an electrode reaction can be produced more uniformly in a reaction system.

As an example, the configuration of a nickel-zinc storage battery will be described below.
The nickel-zinc storage battery includes the zinc negative electrode, a nickel positive electrode, a separator that separates the positive electrode and the negative electrode, an electrolyte and an electrolytic solution, an assembly including them, and a holding container.
There is no restriction | limiting in particular as a nickel electrode, It is also possible to use the nickel electrode used for a nickel hydrogen battery, a nickel metal hydride battery (nickel metal hydride alloy battery), a nickel cadmium battery, etc. The inner walls of the assembly and the holding container are made of a material that does not deteriorate due to corrosion or reaction in the process of using the battery. It is also possible to use a container used for an alkaline battery or a zinc-air battery. The storage battery is a single type, single type, single type, single type, single type, single type, single type, R123A type, cylindrical type such as R-1 / 3N type, etc .; square type such as 9V type, 006P type, etc. A button type; a coin type; a laminate type; a laminated type; a type in which positive and negative plates formed into strips are alternately sandwiched between pleated separators, a sealed type, an open type, or a vent type Good. You may have the site | part which reserves the gas generated in the process of using a battery.

The battery manufacturing process of the present invention may be a wet process or a dry process. In the wet process, for example, the positive electrode current collector is coated with a positive electrode composition paste or slurry, the negative electrode current collector is coated with a negative electrode composition paste or slurry, and the coated electrode sheet is dried and compressed. After cutting and cleaning, the cut electrodes and separator are stacked in layers to form a battery assembly. The dry process is, for example, a process using electrode component powder or a granular dry mixture instead of slurry or paste. (1) The negative electrode composition is applied to the current collector in a dry state, and (2) the positive electrode in a dry state. The composition is applied to the current collector, (3) a separator is placed between the sheets (1) and (2) to form a layered structure, and a battery assembly is formed. (4) The battery assembly of (3) is wound. A three-dimensional structure is formed by attaching or folding. The electrode may be wrapped with a separator or the like or coated with them. The positive electrode and the negative electrode may also serve as a container constituting the battery. As the step of attaching the terminal, spot welding, ultrasonic welding, laser welding, soldering, or any other conductive joining method suitable for the material of the terminal and the current collector is selected. During the manufacturing process or storage of the battery, the battery may be in a (partial) charged state or in a discharged state.

When the battery of the present invention is a storage battery, the charge / discharge rate of the storage battery is preferably 0.01 C or more and 100 C or less. More preferably, it is 0.05C or more and 80C or less, More preferably, it is 0.1C or more and 60C or less, Especially preferably, it is 0.1C or more and 30C or less. It is preferable that the storage battery can be used in both a cold region and a tropical region on the earth, and it is preferable that the storage battery can be used at a temperature of −50 ° C. to 100 ° C.

The battery electrode of the present invention has the above-described configuration, and when the battery is configured using the battery electrode of the present invention, the shape change and dendrite formation of the electrode can be sufficiently controlled, and the life is extended. be able to. Moreover, hydrogen generation can be suppressed.

The present invention will be described in more detail with reference to the following examples. However, the present invention is not limited to these examples.
The average particle size was measured by the method described above.

Example 1
A copper mesh obtained by kneading a polyolefin aqueous dispersion (Mitsui Chemicals Chemipearl S100), polytetrafluoroethylene, and zinc oxide (average particle size 1 μm) at a mass ratio (solid content ratio) of 1: 3: 96. After being rolled and pasted, it was dried to obtain a negative electrode.
Zinc electrode prepared above as a negative electrode, nickel electrode as a positive electrode, an electrode charged with 50% of the same electrode as the positive electrode as a reference electrode, a non-woven fabric placed between the positive electrode and the negative electrode, and 8M hydroxylation saturated with zinc oxide as an electrolyte A triode cell was constructed using an aqueous potassium solution, and a charge / discharge cycle test was conducted. Electrode area and 1.948cm ^2, the current value is 25mA / cm ² (charge and discharge time: 1 hour each) it was. At this time, zinc oxide was eluted with charge and discharge, and a network structure of polyolefin with a large number of pores having a particle diameter of 1 μm of zinc oxide was formed. As a result, stable charge / discharge was possible without reducing the Coulomb efficiency for 200 cycles or more as charge / discharge characteristics. In addition, generation of hydrogen and generation / growth of dendrites were not observed.

(Example 2)
A non-woven fabric of 100 μm thickness made of polyamide on one side of a paste (200 μm thickness) obtained by kneading polytetrafluoroethylene and zinc oxide (average particle size 1 μm) at a mass ratio (solid content ratio) of 4:96. Was attached to form a negative electrode active material layer and a structure on the layer.
The prepared negative electrode active material layer and the structure on the layer, and a copper mesh as the negative electrode current collector are brought into contact with the structure (nonwoven fabric) toward the negative electrode current collector side by physical stress when the battery is assembled. Using a negative electrode, a nickel electrode as a positive electrode, an electrode charged with 50% of the same electrode as the positive electrode as a reference electrode, a non-woven fabric placed between the positive electrode and the negative electrode, and using an 8M potassium hydroxide aqueous solution saturated with zinc oxide as an electrolyte A triode cell was constructed and a charge / discharge cycle test was performed. Electrode area and 1.948cm ^2, the current value is 25mA / cm ² (charge and discharge time: 1 hour each) it was. At this time, it is considered that zinc oxide is eluted with charge and discharge, becomes supersaturated in the network structure of the structure (nonwoven fabric), and precipitates again as zinc oxide in the network structure. As a result, stable charge / discharge was possible without lowering the Coulomb efficiency for 100 cycles or more as charge / discharge characteristics, and the shape change of the zinc negative electrode was also suppressed. In addition, generation of hydrogen and generation / growth of dendrites were not observed.

In Example 2, the active material is zinc oxide, and zinc acid ions that have dissolved from the active material layer contribute to the electrode reaction in the vicinity of the electrode. When the active material layer / nonwoven fabric layer / current collector is laminated in this order, when an electrode reaction occurs, a chemical change occurs from zincate ion to zinc during charging and from zinc to zincate ion during discharging in the vicinity of the electrode. . Here, since the non-woven fabric (porous body) is disposed in the vicinity of the electrode, the zincate ions are likely to be supersaturated in the pores of the porous body, and the zincate ions are supersaturated. Zinc oxide is formed in the body pores. That is, although the initial state was separated from the active material layer / nonwoven fabric layer / current collector, the positions of the active material-containing nonwoven fabric layer / electrode and the active material shift as charging and discharging are performed. Also by this, the structure of the electrode which has the active material layer which concerns on this invention, and the structure in this active material layer and / or on an active material layer is implement | achieved.

In the above examples, the structure has a structure in which voids are randomly connected or a non-woven fabric formed by entwining a plurality of fibers, but the anion is supersaturated mainly in the vicinity of the electrode. Therefore, the active material can be controlled to re-deposit in the vicinity of the electrode. As a result, the electrode shape change can be remarkably suppressed, the life of the battery can be extended, and the generation of hydrogen can be suppressed. The mechanism capable of physically suppressing the short circuit is the same in the case of using a structure that can inhibit the anion eluted during discharge from leaving the active material layer.

The above examples relate to a zinc negative electrode or a nickel / zinc battery using the zinc negative electrode. This is a preferred embodiment of the present invention, but the present invention is also applicable to various other electrodes and batteries. As long as such a structure is used, the effects of the present invention can be exhibited. Therefore, from the results of the above examples, it is proved that the present invention can be applied in various technical forms of the present invention and in various forms disclosed in the present specification, and advantageous effects can be exhibited.

Claims (6)

A battery electrode comprising a current collector and an active material layer containing active material particles,
The electrode has a structure composed of an electrically insulating material on the active material layer ,
The structure Chi also a structure that inhibits the withdrawal from the active material layer of ions from the active material particles, the ions may void portion can pass, airspace are holes granular <br / > A battery electrode characterized by that. A battery electrode comprising a current collector and an active material layer containing active material particles,
The electrode has a structure composed of an electrically insulating material on the active material layer,
The structure has a structure that inhibits the detachment of ions derived from the active material particles from the active material layer, and is configured by entwining a plurality of fibers.
The battery electrode characterized by the above-mentioned. A battery electrode comprising a current collector and an active material layer containing active material particles,
The electrode has a structure composed of an electrically insulating material on the active material layer,
The structure has a structure that inhibits the detachment of ions derived from the active material particles from the active material layer, has a void through which the ions can pass, and does not overlap the positions of the holes in the sheet with through holes. It is composed of a stack of multiple sheets, and the gaps are in regular communication.
The battery electrode characterized by the above-mentioned. The battery electrode according to claim 1 , wherein the structure has a structure in which the voids are in random communication. The active material particles, battery electrode according to any one of claims 1 to 4, characterized in that it contains zinc-containing compound. Battery electrode according to any one of claims 1 to 5, and a battery, characterized in that it comprises an electrolyte.