JP6148873B2 - Zinc negative electrode mixture, zinc negative electrode and battery - Google Patents

Description

The present invention relates to a zinc negative electrode mixture, a zinc negative electrode, and a battery. More specifically, the present invention relates to a zinc negative electrode mixture that uses zinc as a negative electrode active material, is excellent in economy and safety, and can be suitably used for forming a negative electrode of a battery, and relates to a zinc negative electrode and a battery formed using the same. .

A negative electrode mixture is a material that includes a negative electrode active material and forms a negative electrode of a battery. Among them, a zinc negative electrode mixture using zinc as a negative electrode active material has been studied for a long time with the spread of batteries. Is. Examples of batteries using zinc as a negative electrode include primary batteries, secondary batteries (storage batteries), air batteries, and the like. For example, air / zinc batteries using oxygen in the air as the positive electrode active material, nickel-containing compounds as the positive electrode active material Research and development of nickel / zinc batteries using manganese, manganese / zinc batteries and zinc ion batteries using manganese-containing compounds as the positive electrode active material, and silver / zinc batteries using silver oxide as the positive electrode active material, especially air / zinc Primary batteries, manganese / zinc primary batteries, and silver / zinc primary batteries have been put into practical use and are widely used in the world. On the other hand, in recent years, the importance of the development and improvement of batteries has increased in many industrial fields from portable devices to automobiles, etc., and new batteries that are superior mainly in terms of battery performance and secondary battery formation. Various systems have been developed and improved.

Conventionally researched and developed batteries using zinc as a negative electrode include zinc or zinc oxide as a main component, and indium oxide or hydroxide, thallium oxide or hydroxide, and gallium as additives. , A zinc electrode containing at least one oxide or hydroxide selected from the metal group consisting of cadmium, lead, tin, bismuth and mercury, the total amount of additives being 1 to 15% by weight based on the zinc electrode An alkaline zinc storage battery is disclosed (for example, see Patent Document 1). In addition, a negative electrode mainly composed of zinc oxide and metallic zinc, to which an additive, a conductive agent or the like is added, a positive electrode made of a chargeable substance, a separator interposed between these positive and negative electrodes, In the alkaline zinc storage battery, the zinc oxide has a particle size of 1 μm or less and the metal zinc has a particle size of 10 μm or less, and the additive and conductive agent have a particle size of the zinc oxide and metal. An alkaline zinc storage battery having a maximum particle diameter of zinc or less is disclosed (for example, see Patent Document 2). Furthermore, it has a plate-shaped current collector and an electrode material layer containing 35% by weight or more of a main material composed of particles having an average particle size of 0.5 to 60 μm on one or both surfaces of the plate-shaped current collector, The porosity of the electrode material layer is in the range of 0.10 to 0.86, and the main material in the electrode material layer is composed of metal tin or a tin alloy having a crystallite size in the range of 10 to 50 nm. The current collector is used for a negative electrode of a secondary battery using a redox reaction of lithium made of one or more kinds of metal materials selected from copper, nickel, iron, stainless steel, and titanium. An electrode structure is disclosed (for example, see Patent Document 3). Furthermore, it is disclosed that hydrogen generation can be suppressed by depositing indium on zinc and forming an alloy of zinc and indium (see, for example, Non-Patent Document 1).

JP-A 61-96666 JP-A-1-134862 Japanese Patent No. 3619000

Yuichi Sato, 5 others, “Journal of Power Sources”, 1992, vol. 38, p. 317-325

As described above, various types of batteries using zinc as a negative electrode have been studied. However, as batteries using zinc as a negative electrode are developed, new batteries using other elements as negative electrodes have been developed. It was no longer mainstream. However, the present inventors, when using zinc for the negative electrode in this way, the zinc negative electrode is inexpensive and a water-containing electrolyte can be used. In that case, in addition to high safety, the energy density is also high. From such a viewpoint, attention was paid to the possibility of being able to be suitably used in various applications. And when examining the performance aspect of the battery using zinc as the negative electrode, in order to satisfy the performance required for the battery used in recent years, for example, the expression of stable high capacity and high energy density and suppression of self-discharge In addition to the remaining issues, secondary batteries have poor battery performance (charging / discharging cycle characteristics) when charging and discharging are repeated, that is, the battery life is short and the battery life is long. I found. If such a problem is solved, there is a possibility that it can be used in many industrial fields from portable devices to automobiles and the like as a battery that can achieve both economy, safety and performance.

The present invention has been made in view of the above-described situation, and is formed using a zinc negative electrode mixture that can stably express high capacity and high energy density and suppress self-discharge. An object is to provide a zinc negative electrode and a battery.

The inventors of the present invention have disclosed that zinc is used as a negative electrode active material so that the battery stably exhibits high capacity and high energy density and self-discharge is suppressed, and particularly in a secondary battery, charge / discharge cycle characteristics are further improved. Various studies were made on a zinc negative electrode mixture suitably used for forming the negative electrode of the battery. Here, the present inventors paid attention to a zinc negative electrode mixture containing zinc oxide, and studied various chemical and physical characteristics such as the density and crystallite diameter of the zinc oxide particles. When a zinc negative electrode is formed using zinc oxide particles having a tap density of a specific value or more and / or zinc oxide particles having a crystallite diameter of a specific value or more, the self-discharge of the battery is reduced as compared with a conventional zinc negative electrode. It has been found that, in the secondary battery, the charge / discharge cycle characteristics of the battery can be improved and the battery life can be extended. As described above, the present invention has found that the tap density and crystallite diameter of zinc oxide particles, which have not been known so far, affect the self-discharge and the like of a battery configured using the zinc oxide. In the agent, the above problem is brilliant by including zinc oxide having a tap density of particles of 0.77 g / mL or more and / or zinc oxide having crystallites having a crystallite diameter of 600 mm or more in the particles. Thus, the present invention has been achieved.

That is, this invention is a zinc negative electrode mixture containing zinc oxide, Comprising: The said zinc oxide is a zinc negative electrode mixture whose particle | grain tap density is 0.77 g / mL or more.

The present invention is also a zinc negative electrode mixture containing zinc oxide, wherein the zinc oxide is also a zinc negative electrode mixture in which crystallites having a crystallite diameter of 600 mm or more are present in particles.
The present invention is described in detail below.
In addition, the form which combined two or more each preferable structure of this invention described below is also a preferable form of this invention.

The zinc negative electrode mixture of the present invention has at least one of the requirements that the tap density of the particles is 0.77 g / mL or more, or that the crystallites having a crystallite diameter of 600 mm or more exist in the particles. What is necessary is just to contain the zinc oxide to satisfy | fill. In the following, a zinc negative electrode mixture containing zinc oxide having a tap density of 0.77 g / mL or more is referred to as a first zinc negative electrode mixture of the present invention, and the crystallite has a crystallite diameter of 600 mm or more in the particles. A zinc negative electrode mixture containing zinc oxide in which is present is described as a second zinc negative electrode mixture of the present invention. Moreover, the 1st zinc negative electrode mixture of this invention and the 2nd zinc negative electrode mixture are match | combined, and it describes as the zinc negative electrode mixture of this invention. The first zinc negative electrode mixture of the present invention and the second zinc negative electrode mixture have the same structure containing zinc oxide, and when a zinc negative electrode is formed, a high capacity and high energy density are stably expressed. In terms of suppressing self-discharge, at least the technical significance of the invention is common or closely related.

The 1st zinc negative electrode mixture of this invention contains the zinc oxide whose tap density of particle | grains is 0.77 g / mL or more. When a zinc negative electrode formed from such a zinc negative electrode mixture containing zinc oxide is used, the battery can stably exhibit high capacity and high energy density and suppress self-discharge. In, the charge / discharge cycle characteristics can be improved and the life of the battery can be extended. The reason can be considered as follows.
That is, in a battery using a zinc negative electrode, (1) deterioration of battery performance due to morphological change / passive formation of the zinc negative electrode active material, (2) self-discharge during charge, (3) current collection during charge / discharge There are major problems such as decomposition of water caused by contact of the aqueous electrolyte with the body and dissociation of the current collector and the active material layer. Here, in the negative electrode in which zinc oxide is formed as one of the active materials on the current collector, when the tap density of the zinc oxide particles is large, a layer having a high active material density is simply and accurately formed on the current collector. It can be formed, the electron conductivity and ionic conductivity are improved, and at the same time, the current concentration in the active material layer and the contact between the active material and the electrolyte during charging state are minimized, and the zinc oxide particles The gap between the particles (conducting aids, binders, thickeners, etc. may be present between the particles) and the zinc oxide and the current collector is small, and the water contained in the aqueous electrolyte is excessive. It will also prevent penetration. As a result, it is considered that the above problems can be suppressed and battery performance can be improved.
In addition, the present inventors also show that the effect of suppressing the above problem is similarly exerted even when the zinc negative electrode mixture contains zinc oxide in which particles having a crystallite diameter of 600 mm or more exist. I found. This is because the zinc oxide particles used as one of the active materials contain crystallites having a crystallite diameter of 600 mm or more, so that the contact between the zinc oxide particles, or the zinc oxide and the conductive auxiliary agent, the binder. In addition, the contact with the thickener and the like is ensured and dense, and the electronic conductivity and the ionic conductivity are improved. At the same time, the current concentration in the active material layer and the contact between the active material and the electrolyte during charging are minimized. In addition, the zinc oxide particles (conducting aids, binders, thickeners, etc. may be present between the particles) and the gap between the zinc oxide and the current collector are small, and the aqueous electrolyte solution It also prevents the contained water from penetrating to the current collector excessively. As a result, it is speculated that the above problems can be suppressed and battery performance can be improved.

As long as the zinc negative electrode mixture of the present invention contains zinc oxide having a tap density of particles of 0.77 g / mL or more and / or zinc oxide having crystallites having a crystallite diameter of 600 mm or more in the particles, The component which acts as another active material may be included. The zinc negative electrode mixture of the present invention corresponds to at least one of zinc oxide having a particle tap density of 0.77 g / mL or more and zinc oxide having a crystallite having a crystallite diameter of 600 mm or more in the particle. When the ratio of the total amount of particles is about 100% by mass of the total amount of the zinc negative electrode mixture and the zinc negative electrode mixture is close to a fully charged state (SOC≈100%), 0.001% by mass The above is preferable. More preferably, it is 0.01 mass% or more, More preferably, it is 0.05 mass% or more, More preferably, it is 0.1 mass% or more, Especially preferably, it is 0.5 mass% or more is there. In addition, when the zinc oxide is prepared in a state where the zinc negative electrode mixture is close to the discharged state (DOD≈100%) with respect to 100% by mass of the total amount of the zinc negative electrode mixture, it is 100% by mass or less. It is preferable. More preferably, it is 99.999 mass% or less, More preferably, it is 99.99 mass% or less, More preferably, it is 99.9 mass% or less, Most preferably, it is 99 mass% or less. In addition, 100 mass% of the total amount of the zinc negative electrode mixture of the present invention refers to a solid content not containing water or an organic solvent. Further, with respect to 100% by mass of the total amount of components acting as an active material contained in the zinc negative electrode mixture, zinc oxide having a particle tap density of 0.77 g / mL or more and a crystal having a crystallite diameter of 600 mm or more. The ratio of the total amount of particles corresponding to at least one of the zinc oxide containing the child is preferably 5% by mass or more, more preferably 10% by mass or more, and still more preferably 20% by mass. That's it. Zinc oxide having a particle tap density of 0.77 g / mL or more and / or a crystallite having a crystallite diameter of 600 mm or more in such a range with respect to the total amount of components acting as an active material. By including the existing zinc oxide, the effect of the present invention is further exhibited. The total amount of components that act as the active material contained in the zinc negative electrode mixture is zinc oxide having a particle tap density of 0.77 g / mL or more and / or crystallites having a crystallite diameter of 600 mm or more in the particles. It may be made of zinc oxide.

Examples of the component that acts as the other active material include zinc-containing compounds other than zinc oxide. The zinc-containing compound other than the zinc oxide includes, for example, zinc oxide other than zinc oxide having a specified tap density and / or crystallite diameter as described above, conductive zinc oxide, zinc metal, zinc powder, zinc fiber, water Zinc oxide, zinc sulfide, tetrahydroxyzinc alkali metal salts, tetrahydroxyzinc alkaline earth metal salts, zinc halides such as zinc fluoride, zinc carboxylate compounds, zinc alloys, zinc borate, zinc phosphate, phosphoric acid At least one element selected from the group consisting of elements belonging to Groups 1 to 17 of the periodic table represented by zinc hydrogen, zinc silicate, zinc aluminate, carbonate, hydrogen carbonate, nitrate, sulfate, etc. Examples thereof include zinc (alloy) compounds, organic zinc compounds, and zinc compound salts. Among these, zinc oxide other than zinc oxide whose tap density and / or crystallite diameter is specified as described above, conductive zinc oxide, zinc metal, zinc powder, zinc fiber, zinc hydroxide, tetrahydroxy zinc alkali metal More preferred are salts, tetrahydroxyzinc alkaline earth metal salts, zinc halides such as zinc fluoride, zinc carboxylate compounds, zinc alloys, zinc borate, zinc phosphate, zinc silicate, zinc aluminate, and zinc carbonate. The zinc metal and zinc alloy may be zinc metal used for alkaline batteries and air batteries, and zinc alloy used for alkaline batteries and air batteries, respectively.
Here, elements (for example, phosphorus and boron) belonging to Groups 1 to 17 of the periodic table other than zinc contained in the precursor (for example, zinc phosphate and zinc borate) when introducing the zinc active material are: The element itself does not become an active material but acts as an element belonging to Groups 1 to 17 of the periodic table described later.

Moreover, it is preferable that the zinc negative electrode mixture of this invention contains the zinc oxide in which the tap density of particle | grains is 0.77 g / mL or more, and the crystallite with a crystallite diameter of 600 or more exists in particle | grains. Here, the tap density of the particles is 0.77 g / mL or more and the crystallite diameter of the particles is 600 mm or more with respect to 100% by mass of the total amount of the components acting as the active material contained in the zinc negative electrode mixture. When the ratio of zinc oxide in which crystallites are present is made in a state where the zinc negative electrode mixture is close to a fully charged state (SOC≈100%) with respect to 100% by mass of the total amount of the zinc negative electrode mixture, it is 0. It is preferably 0.001% by mass or more. More preferably, it is 0.01 mass% or more, More preferably, it is 0.05 mass% or more, More preferably, it is 0.1 mass% or more, Especially preferably, it is 0.5 mass% or more is there. Further, when the zinc oxide mixture is prepared in a state in which the zinc negative electrode mixture is close to the discharge state (DOD≈100%) with respect to 100% by mass of the total amount of the zinc negative electrode mixture, it is 100% by mass or less. It is preferable that More preferably, it is 99.999 mass% or less, More preferably, it is 99.99 mass% or less, More preferably, it is 99.9 mass% or less, Most preferably, it is 99 mass% or less. As long as it contains zinc oxide having a particle tap density of 0.77 g / mL or more and / or zinc oxide having a crystallite diameter of 600 mm or more in the particle, other components that act as active materials May be included. Preferably, with respect to 100% by mass of the total amount of components acting as an active material contained in the zinc negative electrode mixture, the particle size of the crystal is 600 mm or more in zinc oxide and particles having a tap density of 0.77 g / mL or more. It is preferable that the ratio of the total amount of particles corresponding to at least one of zinc oxides containing crystallites is 5% by mass or more. More preferably, it is 10 mass% or more, More preferably, it is 20 mass% or more. In such a range, the effect of the present invention is more sufficiently obtained by including zinc oxide in which the particle tap density is 0.77 g / mL or more and the crystallites having a crystallite diameter of 600 mm or more are present in the particles. Will be demonstrated. The total amount of components acting as an active material contained in the zinc negative electrode mixture is from zinc oxide in which the tap density of the particles is 0.77 g / mL or more and the crystallites having a crystallite diameter of 600 mm or more are present in the particles. It may be.

The tap density of the zinc oxide particles is preferably 0.80 g / mL or more. More preferably, it is 0.82 g / mL or more. The tap density is preferably 3.00 g / mL or less. More preferably, it is 2.00 g / mL or less, More preferably, it is 1.00 g / mL or less.
The tap density was measured by passing zinc oxide through a sieve having an opening of 500 μm, gently placing it in a 20 mL graduated cylinder, measuring the mass, and subsequently tapping it until almost no volume change was observed (700 times). It can be obtained by reading the volume at the time.

The crystallite size present in the zinc oxide particles is preferably 620 mm or more. The crystallite diameter is preferably 1500 mm or less. More preferably, it is 1350 mm or less.
The crystallite diameter of the zinc oxide in the present application is measured with a fully automatic horizontal multi-purpose X-ray diffractometer SmartLab manufactured by Rigaku, and the half-value width and diffraction angle of the (1, 0, 1) plane are substituted into the following Scherrer equation: And calculated.
Scherrer formula crystallite size D (子) = K × λ / (β × cos θ)
K: Scherrer constant λ: wavelength of X-ray tube used β: diffraction angle spread depending on crystallite size θ: diffraction angle 2θ / θ
The crystal plane of zinc oxide to be noted when performing the above measurement and analysis is not particularly limited, and the crystallite diameter at an arbitrary Miller index may be 600 mm or more, but the above-described (1, 0, 1) plane is focused. I found what I should do in a series of studies.

Particles having a tap density in the above range and particles having a crystallite diameter in the above range are, for example, (1) a method of heating molten metal zinc and oxidizing generated zinc vapor with air, (2) It is possible to manufacture by a method of obtaining particles with a desired tap density by a method in which a precipitate formed by adding a soda ash solution to an aqueous zinc salt solution such as zinc sulfate or zinc chloride is washed with water, dried and then fired. is there. At this time, the particle diameter of the zinc oxide particles can be set to a desired value by an operation such as classification.

Examples of the shape of the zinc oxide particles include fine powder, powder, granular, fine granular, scaly, fibrous, granular, polyhedral, rod-shaped, rectangular, cylindrical, curved surface-containing, etc. It is done.

The zinc oxide in which the tap density of the particle is 0.77 g / mL or more and / or the zinc oxide in which the particle has a crystallite diameter of 600 mm or more is 0.01 m ² / g or more. It is preferable that More preferably, it is 0.1 m < ² > / g or more as a specific surface area, More preferably, it is 0.2 m < ² > / g or more. Moreover, it is preferable that this specific surface area is 200 m < ² > / g or less.
The specific surface area can be measured by a specific surface area measuring device or the like. 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 zinc oxide particles preferably include particles satisfying the following average particle diameter and / or aspect ratio. Further, it is more preferable that the zinc oxide particles satisfy the following average particle diameter and / or aspect ratio.
The average particle diameter of the zinc oxide particles is preferably 1 nm to 500 μm, more preferably 5 nm to 100 μm, still more preferably 10 nm to 20 μm, and particularly preferably 100 nm to 10 μm.
The zinc oxide particles are preferably 100 nm to 100 μm in average particle size when measured with a particle size distribution measuring device after adding and irradiating and dispersing zinc oxide particles in ion exchange water for 5 minutes. More preferably, it is 200 nm-50 micrometers, More preferably, it is 300 nm-10 micrometers. The mode diameter is preferably 50 nm to 20 μm. More preferably, it is 70 nm-10 micrometers, More preferably, it is 100 nm-5 micrometers. The median diameter is preferably 100 nm to 10 μm. More preferably, it is 150 nm-7 micrometers, More preferably, it is 500 nm-5 micrometers.
The aspect ratio (vertical / horizontal) of the zinc oxide particles can be measured, for example, when the zinc oxide particles can be measured in a rectangular shape, a cylindrical shape, a spherical shape, a curved surface-containing shape, a polyhedral shape, a scale shape, a rod shape, or the like. Is preferably 1.1 to 100,000, more preferably 1.2 to 50,000, and still more preferably 1.5 to 10,000. When particles that satisfy the above average particle size and aspect ratio are not included, cycle characteristics decrease due to shape change or passive formation of the negative electrode active material, and self-discharge occurs during charging or storage in the charged state. There is a possibility of becoming easy.
The average particle diameter can be measured by a transmission electron microscope (TEM), a scanning electron microscope (SEM), a particle size distribution measuring device, powder X-ray diffraction (XRD), or the like. The aspect ratio (vertical / horizontal) is, for example, from the shape of particles observed by TEM or SEM, in the case of a rectangular shape, the longest side is vertical, the second longest side is horizontal, and the vertical length is It can be obtained by dividing by the horizontal length. In the case of a cylinder, sphere, curved surface, polyhedron, etc., when a certain part is placed on the bottom so that the aspect ratio is maximized, it is projected from the direction that maximizes the aspect ratio. Measure the length of a point that is farthest from a point in a two-dimensional shape that can be made, with the longest side as the vertical, the longest side of the straight line passing through the vertical center point as the horizontal, and the vertical length as the horizontal It can be obtained by dividing by the length of.

The zinc negative electrode mixture of the present invention may further contain a conductive aid. Examples of the conductive auxiliary include conductive carbon, conductive ceramic, zinc used in zinc powder, zinc powder, zinc alloy, (alkaline) dry batteries and air batteries (hereinafter also referred to as metal zinc). Can be used. Conductive carbon includes graphite, glassy carbon, amorphous carbon, graphitizable carbon, non-graphitizable carbon, carbon nanofoam, activated carbon, graphene, nanographene, graphene nanoribbon, fullerene, carbon black, carbon fiber, fibrous carbon, carbon Nanotubes, carbon nanohorns, Vulcan, ketjen black, acetylene black and the like can be mentioned. Among these, graphite, graphitizable carbon, non-graphitizable carbon, graphene, carbon black, carbon fiber, fibrous carbon, carbon nanotube, Vulcan, Ketjen black, acetylene black, and metallic zinc are preferable.
The metallic zinc may be added as a negative electrode mixture in the preparation stage of the negative electrode, or metal zinc generated from zinc oxide or the zinc-containing compound, etc. when conducting charge / discharge in a secondary battery as a conductive auxiliary agent. It can also be used. In this case, zinc oxide and the zinc-containing compound function as a negative electrode active material and a conductive additive.

As a compounding quantity of the said conductive support agent, it is preferable that it is 0.001-99.999 mass% with respect to 100 mass% of whole quantity of a zinc negative electrode mixture. When metallic zinc is used as a conductive aid during the preparation of the negative electrode mixture, metallic zinc is not a component that acts as an active material, but is calculated as a conductive aid. In addition, metal zinc generated during charging / discharging from zinc oxide, zinc hydroxide, etc., which are zinc-containing compounds, can also be used as a conductive aid in the system, but in that case, it is used when preparing the negative electrode mixture The zinc-containing compound to be calculated is considered as a component acting as an active material. When the blending amount of the conductive auxiliary is in such a range, when the zinc negative electrode formed from the zinc negative electrode mixture is used as the negative electrode of the battery, better battery performance is exhibited. More preferably, it is 0.01-99.99 mass%, More preferably, it is 0.05-99.99 mass%.

The zinc negative electrode mixture of the present invention may contain components other than the component acting as an active material and the conductive additive, but when the zinc negative electrode mixture of the present invention further contains other components, the blending amount thereof Is preferably 0.001 to 80% by mass relative to 100% by mass of the total amount of the zinc negative electrode mixture. More preferably, it is 0.01-70 mass%, More preferably, it is 0.01-60 mass%.

Examples of the other components include compounds having at least one element selected from the group consisting of elements belonging to Groups 1 to 17 of the periodic table, organic compounds, organic compound salts, and the like. Here, in the case of a battery configured using a water-containing electrolyte as an electrolyte, it is preferable to an organic solvent-based electrolyte from the viewpoint of safety. A side reaction that a decomposition reaction of water proceeds and hydrogen is generated may occur due to a chemical reaction. However, the zinc negative electrode mixture of the present invention contains, as another component, a compound, organic compound, or organic compound salt having at least one element selected from the group consisting of elements belonging to Groups 1 to 17 of the periodic table. As a result, it is possible to effectively suppress the deterioration of battery performance due to the shape change / passivation formation of the zinc negative electrode active material, self-discharge during charging, hydrogen generation due to water decomposition, etc. Discharge characteristics are further improved. As described above, the zinc negative electrode mixture of the present invention is oxidized with zinc oxide having a particle tap density of 0.77 g / mL or more and / or crystallites having a crystallite diameter of 600 mm or more in the particles. Since zinc is contained, the zinc negative electrode formed using such a zinc negative electrode mixture can exhibit the above-described effects and the like. However, on the other hand, for example, it is difficult to thermodynamically completely suppress the side reaction of hydrogen generation due to water decomposition. Therefore, the specific zinc oxide in the present invention is not used in the zinc negative electrode mixture. When used as a component, as another component, a battery having at least one element selected from the group consisting of elements belonging to Groups 1 to 17 of the periodic table, an organic compound, and an organic compound salt are used in combination. The effect of suppressing the self-discharge can be made synergistically excellent and has great technical significance. That is, the zinc negative electrode mixture of the present invention further contains another component, and the other component is a compound having at least one element selected from the group consisting of elements belonging to Groups 1 to 17 of the periodic table. The inclusion of an organic compound and / or an organic compound salt is also one preferred embodiment of the present invention. More preferred are compounds, organic compounds, and organic compound salts having at least one element selected from the group consisting of elements belonging to Groups 1 to 6, and 10 to 17 of the periodic table.

In addition, it corresponds to any of a compound, an organic compound, and an organic compound salt having at least one element selected from the group consisting of elements belonging to Groups 1 to 17 of the periodic table, which are included in the other components. The ratio of the total amount of things is preferably 0.1% by mass or more with respect to 100% by mass of the total amount of other components. More preferably, it is 0.5 mass% or more, More preferably, it is 1.0 mass% or more. Moreover, it is preferable that the ratio of the said total amount is 100 mass% or less.

Examples of the compound having at least one element selected from the group consisting of elements belonging to Groups 1 to 17 of the periodic table include Ag, Al, Au, Ba, B, Be, Bi, Ca, Cd, Ce, and Co. , Cr, Cs, Cu, F, Fe, Ga, Ge, Hf, Hg, In, K, Li, Mg, Mn, Mo, Na, Nb, Ni, Pd, Pt, Pb, Rb, Ru, Sc, Si , P, S, Se, Sn, Sr, Sb, Ta, Te, Ti, Tl, V, W, Y, Zr, selected from the group consisting of elements belonging to Groups 1 to 17 of the periodic table Oxides of at least one element; hydroxides; layered double hydroxides; sulfides; halogen compounds; carboxylate compounds; carbonate compounds; hydrogen carbonate compounds; nitric acid compounds; sulfite compounds; Compound; Al Phosphate compounds; phosphoric acid compounds; hydrogen phosphate compound; boric acid compound; onium salts; ammonium salts; solid solutions; alloys. These elements may be doped in zinc oxide, or may be contained in a zinc-containing compound or a conductive additive.
Among these, an oxide, hydroxide, layered double hydroxide, halogen compound, carboxylate compound, carbonate compound of at least one element selected from the group consisting of elements belonging to Groups 1 to 17 of the periodic table, Sulfuric acid compounds, sulfonic acid compounds, silicic acid compounds, phosphoric acid compounds, boric acid compounds, onium salts, ammonium salts, solid solutions, and alloys are preferred. More preferably, the other component includes an oxide of at least one element selected from the group consisting of elements belonging to Groups 1 to 6, and Groups 10 to 17 of the periodic table.

Examples of the element in the compound having at least one element selected from the group consisting of elements belonging to Groups 1 to 17 of the periodic table include Ag, Al, Au, Ba, B, Be, Bi, Ca, Cd, and Ce. , Co, Cr, Cs, Cu, F, Fe, Ga, Ge, Hf, Hg, In, K, Li, Mg, Mn, Mo, Na, Nb, Ni, Pd, Pt, Pb, Rb, Ru, Sc Si, P, S, Se, Sn, Sr, Sb, Ta, Te, Ti, Tl, V, W, Y, Zr, and at least one element selected from the group consisting of lanthanoids are preferred. More preferable elements are elements belonging to Groups 1 to 6, 10 to 17 of the periodic table, that is, Ag, Al, Au, Ba, B, Be, Bi, Ca, Cd, Ce, Cr, Cs, Cu, F , Ga, Ge, Hf, Hg, In, K, Li, Mg, Mo, Na, Nb, Ni, Pd, Pt, Pb, Rb, Sc, Si, P, S, Se, Sn, Sr, Sb, Ta , Te, Ti, Tl, V, W, Y, Zr, and at least one element selected from the group consisting of lanthanoids. More preferably, Ag, Al, Au, Ba, B, Bi, Ca, Cd, Ce, Cr, Cs, Cu, F, Ga, Ge, In, K, Li, Mg, Na, Nb, Ni, Pd, It is at least one element selected from the group consisting of Pb, Sc, Si, P, S, Sn, Sr, Sb, Ta, Te, Ti, Tl, W, Y, Zr, and a lanthanoid.

Specific examples of the compound having at least one element selected from the group consisting of elements belonging to Groups 1 to 17 of the periodic table include silver oxide, aluminum oxide, barium oxide, bismuth oxide, and bismuth-containing composites. Oxide, calcium oxide, calcium-containing composite oxide, lanthanum oxide / cerium oxide / cerium-containing composite oxide / cerium-containing solid solution / lanthanum oxide such as ytterbium oxide, cobalt oxide, cesium oxide, gallium oxide, indium oxide, indium-containing composite Oxides, potassium oxide, lithium oxide, magnesium oxide, sodium oxide, niobium oxide, neodymium oxide, lead oxide, phosphorus oxide, tin oxide, scandium oxide, antimony oxide, titanium oxide, manganese oxide, yttrium oxide, zirconium oxide, scandium oxide Stabilized zirconium oxide, yttrium oxide stabilized zirconium oxide, zirconium-containing composite oxide, chromium oxide, germanium oxide, rubidium oxide, silicon oxide, strontium oxide, tellurium oxide, vanadium oxide, nickel oxide, thallium oxide, gold oxide , Lanthanoid hydroxides such as palladium oxide, copper oxide, cadmium oxide, tungsten oxide, aluminum hydroxide, barium hydroxide, calcium hydroxide, cerium hydroxide, cesium hydroxide, indium hydroxide, potassium hydroxide, lanthanum hydroxide, Magnesium hydroxide, lithium hydroxide, sodium hydroxide, rubidium hydroxide, tin hydroxide, strontium hydroxide, antimony hydroxide, titanium hydroxide, zirconium hydroxide, nickel hydroxide, thallium hydroxide, lithium fluoride, Sodium fluoride, potassium fluoride, magnesium fluoride, calcium fluoride, barium fluoride, scandium fluoride, yttrium fluoride, lanthanide fluoride, titanium fluoride, silver chloride, lithium chloride, magnesium chloride, sodium chloride, rubidium chloride , Tin chloride, silver acetate, barium acetate, bismuth acetate, calcium acetate, calcium tartrate, calcium glutamate, cerium acetate, cesium acetate, gallium acetate, indium acetate, potassium acetate, lanthanum acetate, lithium acetate, magnesium acetate, sodium acetate, tartaric acid Sodium, sodium glutamate, niobium acetate, neodymium acetate, lead acetate, rubidium acetate, tin acetate, strontium acetate, antimony acetate, tellurium acetate, silver carbonate, aluminum carbonate, barium carbonate, bis carbonate Trout, calcium carbonate, cobalt carbonate, cesium carbonate, gallium carbonate, indium carbonate, potassium carbonate, lanthanum carbonate, lithium carbonate, magnesium carbonate, sodium carbonate, lead carbonate, rubidium carbonate, tin carbonate, strontium carbonate, antimony carbonate, aluminum sulfate, Barium sulfate, bismuth sulfate, calcium sulfate, cesium sulfate, cerium sulfate, gallium sulfate, indium sulfate, potassium sulfate, lanthanum sulfate, lithium sulfate, magnesium sulfate, sodium sulfate, lead sulfate, rubidium sulfate, tin sulfate, strontium sulfate, antimony sulfate , Titanium sulfate, tellurium sulfate, vanadium sulfate, zirconium sulfate, calcium lignin sulfonate, aluminum nitrate, barium nitrate, bismuth nitrate, calcium nitrate, cerium nitrate, cesium nitrate, Gallium oxide, indium nitrate, potassium nitrate, lanthanum nitrate, lithium nitrate, magnesium nitrate, sodium nitrate, lead nitrate, rubidium nitrate, tin nitrate, strontium nitrate, antimony nitrate, titanium nitrate, tellurium nitrate, vanadium nitrate, zirconium nitrate, potassium silicate , Calcium silicate, magnesium silicate, barium silicate, potassium phosphate, calcium phosphate, magnesium phosphate, barium phosphate, calcium borate, barium borate, layered double hydroxide (hydrotalcite etc.), clay compound, It is a solid solution such as lipolite, hydroxyapatite, cerium oxide-zirconium oxide, ettringite, and cement.
Compounds such as cerium hydroxide, zirconium hydroxide, layered double hydroxides (hydrotalcite, etc.), hydroxyapatite, ettringite, etc. are used for decomposition reactions and self-decomposition of water at the zinc electrode during charge / discharge and storage in the charged state. It is considered that not only the discharge and the dissolution reaction of the negative electrode active material containing zinc are suppressed, but also the function of increasing the anion conductivity is assumed.

In addition, when the compound having at least one element selected from the group consisting of elements belonging to Group 1 to 17 of the periodic table is made to have a small average particle diameter by nanoparticulation or the like, The side reaction that occurs when the aqueous electrolyte is used can be further effectively suppressed, and the effect of suppressing the self-discharge of the battery can be exhibited more significantly, which is preferable. Thus, the compound having at least one element selected from the group consisting of elements belonging to Groups 1 to 17 of the periodic table preferably has an average particle diameter of 1000 μm or less. More preferably, it is 500 micrometers or less, More preferably, it is 300 micrometers or less, Most preferably, it is 100 micrometers or less. On the other hand, the average particle size is preferably 1 nm or more. More preferably, it is 5 nm or more, More preferably, it is 10 nm or more. The average particle diameter can be measured with a transmission electron microscope (TEM), a scanning electron microscope (SEM), a particle size distribution measuring device, or the like.

The compound having at least one element selected from the group consisting of elements belonging to Groups 1 to 17 of the periodic table preferably has a specific surface area of 0.01 m ² / g or more. More preferably, it is 0.1 m < ² > / g or more, More preferably, it is 0.5 m < ² > / g or more. Moreover, it is preferable that this specific surface area is 500 m < ² > / g or less. The specific surface area can be measured in the same manner as the specific surface area of zinc oxide described above.

Examples of the organic compound and organic compound salt include poly (meth) acrylic acid moiety-containing polymer, poly (meth) acrylate moiety-containing polymer, poly (meth) acrylic ester moiety-containing polymer, poly (α-hydroxymethyl) (Acrylate) site-containing polymer, poly (α-hydroxymethyl acrylate) site-containing polymer, polyacrylonitrile site-containing polymer, polyacrylamide site-containing polymer, polyvinyl alcohol site-containing polymer, polyethylene oxide site-containing polymer, polypropylene oxide site-containing polymer Polymer, polybutene oxide moiety-containing polymer, epoxy ring-opening moiety-containing polymer, polyethylene moiety-containing polymer, polypropylene moiety-containing polymer, polybutene moiety-containing polymer, polyisoprenol moiety-containing Polymer containing, polymethallyl alcohol moiety-containing polymer, polyallyl alcohol moiety-containing polymer, polyisoprene moiety-containing polymer, aromatic ring moiety-containing polymer represented by polystyrene, polymaleimide moiety-containing polymer, polyvinylpyrrolidone moiety-containing polymer, polyacetylene moiety-containing Polymer, polycarbonate moiety-containing polymer, thiopolycarbonate moiety-containing polymer, ketone group moiety-containing polymer, ether group moiety-containing polymer, sulfide group-containing polymer, sulfone group-containing polymer, carbamate group-containing polymer, thiocarbamate group-containing polymer, carbamide group-containing polymer Thiocarbamide group-containing polymer, thiocarboxylic acid (salt) group-containing polymer, ester group-containing polymer, carbonate group-site-containing polymer, thiocarbo Artificial rubber typified by carbonate group-containing polymer, cyclopolymerization site-containing polymer, lignin, styrene butadiene rubber (SBR), agar, betaine site-containing compound, cellulose, cellulose acetate, hydroxyalkyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose Saccharides such as chitin, chitosan, alginic acid (salt), ethylene glycol, polyethylene glycol chain-containing compound, polypropylene glycol chain-containing compound, polybutene glycol chain-containing compound, amino group-containing polymer such as polyethyleneimine, amide group site-containing polymer, poly Peptide moiety-containing polymer, polytetrafluoroethylene moiety-containing polymer, polyvinylidene fluoride moiety-containing polymer, poly (anhydride) maleic acid moiety-containing polymer, polymaleic acid Site-containing polymer, poly (anhydrous) itaconic acid site-containing polymer, polyitaconate site-containing polymer, poly (anhydrous) methylene glutarate site-containing polymer, polymethylene glutarate site-containing polymer, cation / anion exchange membrane, etc. Ion-exchange polymer used, sulfonate, sulfonate moiety-containing polymer, quaternary ammonium salt, quaternary ammonium salt moiety-containing polymer, quaternary phosphonium salt, quaternary phosphonium salt moiety-containing polymer, Isocyanic acid site-containing polymer, isocyanate group-containing polymer, thioisocyanate group-containing polymer, imide group site-containing polymer, oxetane group site-containing polymer, hydroxyl group site-containing polymer, heterocyclic ring and / or ionized heterocyclic site-containing polymer, polymer Alloy, heteroatom-containing poly Examples thereof include limers and low molecular weight surfactants. The above organic compounds and organic compound salts can be used alone or in combination of two or more. When the organic compound and the organic compound salt are polymers, the functional group may be in the main chain or in the side chain, and the main chain may be partially crosslinked.

When the organic compound or organic compound salt is a polymer, the polymer contains a specific site / functional group as long as the polymer has the site / functional group in part. It may contain a monomer unit having no group. When the organic compound or organic compound salt is a polymer, radical polymerization, radical (alternate) copolymerization, anion polymerization, anion (alternate) copolymerization, cationic polymerization, cation (cation) (cation ( (Alternate) copolymerization, graft polymerization, graft (alternate) copolymerization, living polymerization, living (alternate) copolymerization, dispersion polymerization, emulsion polymerization, suspension polymerization, ring-opening polymerization, cyclization polymerization, light, ultraviolet light and electron beam irradiation Can be obtained by polymerization, metathesis polymerization, electrolytic polymerization and the like. At this time, a compound containing at least one element selected from the group consisting of zinc-containing compound particles such as zinc oxide particles, conductive auxiliary agent particles, and elements belonging to Groups 1 to 17 of the periodic table, in the polymer, and It is also possible to incorporate on the surface to form a single particle. The polymer may cause a reaction such as hydrolysis in the electrolytic solution. Moreover, a monomer may be used as an organic compound or an organic compound salt at the time of electrode preparation, and polymerized at the time of charge / discharge.
Organic compounds and organic compound salts improve the dispersibility of the particles, and also efficiently bind the particles, the particles and the current collector, the binder, the thickener, and the active material change of the zinc electrode It is expected to function as a material that exhibits effects such as suppression of the formation of passive substances, dissolution of zinc electrode active materials, improvement of hydrophilicity / hydrophobicity balance, improvement of anion conductivity, and improvement of electron conductivity. When used, side reactions during charge and discharge in which hydrogen is generated by the progress of water decomposition reaction, which can usually occur thermodynamically, morphological change and passive formation and corrosion reaction of zinc electrode active material, and Self-discharge during charging or storage in the charged state is suppressed, and the charge / discharge characteristics, coulomb efficiency, and storage stability of the battery are significantly improved. One of the factors of this effect is that the organic compound or organic compound salt suitably covers or adsorbs the surface of the zinc-containing compound such as zinc oxide, or chemically interacts with the zinc-containing compound such as zinc oxide. It is thought to be derived from the fact that the action is manifested. It has been newly found in the present invention that such an effect is seen in organic compounds and organic compound salts.
Preferably, the organic compound or organic compound salt is a poly (meth) acrylic acid moiety-containing polymer, a poly (meth) acrylate moiety-containing polymer, a poly (meth) acrylate ester moiety-containing polymer, or poly (α-hydroxymethylacrylic acid). Salt) site-containing polymer, poly (α-hydroxymethyl acrylate) site-containing polymer, polyacrylonitrile site-containing polymer, polyacrylamide site-containing polymer, polyvinyl alcohol site-containing polymer, polyethylene oxide site-containing polymer, polypropylene oxide site-containing polymer, Polybutene oxide moiety-containing polymer, epoxy ring-opening moiety-containing polymer, polyethylene moiety-containing polymer, polyisoprenol moiety-containing polymer, polymethallyl alcohol moiety-containing polymer, polyallyl alcohol Polymer containing an alcohol moiety, Polymer containing a polyisoprene moiety, Polymer containing an aromatic ring represented by polystyrene, Polymer containing a polymaleimide moiety, Polymer containing a polyvinylpyrrolidone moiety, Polymer containing a polycarbonate moiety, Polymer containing a ketone moiety, Polymer containing an ether moiety , Sulfide group-containing polymer, sulfone group-containing polymer, carbamate group-containing polymer, thiocarbamate group-containing polymer, carbamide group-containing polymer, thiocarbamide group-containing polymer, ester group-containing polymer, carbonate group site-containing polymer, cyclopolymerization site-containing polymer , Artificial rubber represented by lignin, styrene butadiene rubber (SBR), agar, compound containing betaine moiety, cellulose, cellulose acetate, hydroxyalkyl cellulose, Sugars such as ruboxymethyl cellulose and hydroxyethyl cellulose, ethylene glycol, polyethylene glycol chain-containing compounds, polypropylene glycol chain-containing compounds, polybutene glycol chain-containing compounds, amino group-containing polymers such as polyethyleneimine, amide group-containing polymers, and polypeptide-site-containing Polymer, polytetrafluoroethylene site-containing polymer, polyvinylidene fluoride site-containing polymer, poly (anhydride) maleic acid site-containing polymer, polymaleate site-containing polymer, poly (anhydride) itaconic acid site-containing polymer, polyitaconate site-containing polymer Ion exchange used for poly (anhydrous) methylene glutaric acid moiety-containing polymer, poly (anhydrous) methylene glutarate moiety-containing polymer, cation / anion exchange membrane, etc. Polymer, sulfonate, sulfonate moiety-containing polymer, quaternary ammonium salt, quaternary ammonium salt moiety-containing polymer, quaternary phosphonium salt, quaternary phosphonium salt moiety-containing polymer, imide group moiety-containing polymer An oxetane group-containing polymer, a hydroxyl group-containing polymer, a heterocyclic ring, and / or an ionized heterocyclic moiety-containing polymer, a polymer alloy, a heteroatom-containing polymer, and a low molecular weight surfactant.

The zinc negative electrode mixture of the present invention, together with a zinc-containing compound such as zinc oxide, as necessary, at least one selected from the group consisting of a conductive additive and elements belonging to Groups 1 to 17 of the periodic table. It can be prepared by mixing at least one selected from the group consisting of a compound having an element, an organic compound, and an organic compound salt. For mixing, a mixer, blender, kneader, bead mill, ready mill, ball mill, or the like can be used. During mixing, water, an organic solvent such as methanol, ethanol, propanol, isopropanol, tetrahydrofuran, N-methylpyrrolidone, or a mixed solvent of water and an organic solvent may be added. After mixing, operations such as sieving may be performed in order to align the particles to a desired particle size. 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. For example, after a zinc-containing compound such as zinc oxide and a compound having at least one element selected from the group consisting of elements belonging to Groups 1 to 17 of the periodic table are mixed by a wet method, the liquid component is dried by drying. The solid mixture obtained by removal and the conductive additive may be mixed by a dry method to prepare a zinc negative electrode mixture. Further, a zinc-containing compound and a compound having at least one element selected from the group consisting of elements belonging to Groups 1 to 17 of the periodic table may be alloyed.

The zinc negative electrode mixture of the present invention contains zinc oxide having a particle tap density of 0.77 g / mL or more and / or zinc oxide in which a crystallite having a crystallite diameter of 600 mm or more is present in the particle. Thus, a battery using a zinc negative electrode formed using such a zinc negative electrode mixture can stably exhibit high capacity and high energy density and suppress self-discharge. It becomes. Moreover, in a secondary battery, the charge / discharge cycle characteristics of the battery can be improved and the battery life can be extended. A zinc negative electrode formed using such a zinc negative electrode mixture of the present invention is also one aspect of the present invention. In addition, this zinc negative electrode is normally comprised including a collector and the active material layer formed on this collector using a zinc negative electrode mixture.

Examples of the method for preparing the zinc negative electrode include the following methods. The zinc negative electrode mixture (mixture) of the present invention obtained by the above-described method is at least one compound selected from the group consisting of the above organic compounds, and / or water, an organic solvent such as N-methylpyrrolidone, etc. Kneading with a solvent by a kneader or the like. Next, the obtained slurry or paste mixture is coated, pressure-bonded, adhered, etc. on a copper foil as a current collector so that the film thickness is as constant as possible. Instead of copper foil, for example, electrolytic copper foil, copper foil added with Ni, Zn, Sn, Pb, Hg, Bi, In, Tl, etc., Ni, Zn, Sn, Pb, Hg, Bi, In, Copper foil plated with Tl, copper mesh (expanded metal), copper mesh (expanded metal) with added Ni, Zn, Sn, Pb, Hg, Bi, In, Tl, Ni, Zn, Sn, Pb, Copper mesh plated with Hg / Bi / In / Tl (expanded metal), expanded copper, expanded copper added with Ni / Zn / Sn / Pb / Hg / Bi / In / Tl, Ni / Zn / Sn / Pb -Copper alloy such as foamed copper, brass, etc. plated with Hg, Bi, In, Tl, etc., nickel foil, nickel mesh, nickel with corrosion resistance, Zn, Sn, Pb, Hg, Bi, In, Tl, etc. Lumesh (expanded metal), nickel mesh plated with Zn / Sn / Pb / Hg / Bi / In / Tl, etc., zinc metal, corrosion-resistant zinc metal, Ni / Sn / Pb / Hg / Bi / In / Zinc metal added with Tl, zinc metal plated with Ni, Sn, Pb, Hg, Bi, In, Tl, etc., zinc foil, zinc added with Ni, Sn, Pb, Hg, Bi, In, Tl, etc. Foil, zinc foil plated with Ni, Sn, Pb, Hg, Bi, In, Tl, etc., zinc mesh (expanded metal), zinc mesh with added Ni, Sn, Pb, Hg, Bi, In, Tl, etc. Expanded metal), zinc mesh plated with Ni, Sn, Pb, Hg, Bi, In, Tl, etc. (expanded metal), silver, alkaline batteries It is also possible to use a material used as a current collector or container in an air zinc battery or the like. The slurry or paste mixture may be applied or pressure-bonded to one surface of the current collector, or may be coated, pressure-bonded, or adhered to both surfaces or the entire surface. After coating, it is dried at 0 to 250 ° C. More preferably, it is 15-200 degreeC as drying temperature. The drying time is preferably 4 to 48 hours. Drying may be performed by vacuum drying. Moreover, it is preferable to press with a roll press machine etc. at the pressure of 0.01-20 t after drying. More preferably, the pressing pressure is 0.1 to 15 t. The zinc negative electrode (zinc mixture electrode) thus obtained suppresses concentration of current and decomposition of water in the zinc negative electrode, particularly when used as a negative electrode for a secondary battery. Deterioration due to dendrite growth and generation of hydrogen and oxygen can be suppressed to the maximum. The thickness of the zinc negative electrode is preferably 1 nm to 1000 μm. More preferably, it is 10 nm-600 micrometers, More preferably, it is 20 nm-500 micrometers.

A battery constituted by using the zinc negative electrode, the positive electrode, and the aqueous electrolyte of the present invention is also one aspect of the present invention. The battery of the present invention can further use a separator. The separator is a member that separates the positive electrode and the negative electrode and holds the electrolyte solution to ensure ionic conductivity between the positive electrode and the negative electrode. In addition, in the case of a storage battery using a zinc negative electrode, the zinc electrode active material is prevented from being altered or dendrite is formed, the positive and negative electrodes are moistened, and liquid drainage is avoided.
The separator is not particularly limited, but non-woven fabric, filter paper, polymer containing hydrocarbon moiety such as polyethylene and polypropylene, polymer containing polytetrafluoroethylene moiety, polymer containing polyvinylidene fluoride, cellulose, fibrillated cellulose, viscose rayon. , Cellulose acetate, hydroxyalkyl cellulose, carboxymethyl cellulose, polyvinyl alcohol-containing polymer, cellophane, polystyrene-containing aromatic ring moiety-containing polymer, polyacrylonitrile moiety-containing polymer, polyacrylamide moiety-containing polymer, polyhalogenated vinyl moiety-containing polymer, polyamide moiety-containing Polymers, polyimide site-containing polymers, ester site-containing polymers such as nylon, poly (meth) acrylic acid site-containing polymers, poly ( T) Acrylate moiety-containing polymers, hydroxyl group-containing polymers such as polyisoprenol and poly (meth) allyl alcohol, carbonate group-containing polymers such as polycarbonate, ester group-containing polymers such as polyester, carbamate and carbamide group moieties such as polyurethane Polymer, agar, gel compound, organic-inorganic hybrid (composite) compound, ion exchange membrane polymer, cyclized polymer, sulfonate-containing polymer, quaternary ammonium salt-containing polymer, quaternary phosphonium salt polymer, cyclic hydrocarbon group Inorganic substances such as containing polymers, ether group-containing polymers, ceramics and the like. In the case where the separator is composed of the polymer, the polymer contains a specific site / functional group if the polymer includes a monomer unit having the site / functional group in part. What is necessary is just to include the monomer unit which does not have the said site | part and functional group. In other words, the polymer may be a copolymer.
The separator may include a compound having at least one element selected from the group consisting of elements belonging to Groups 1 to 17 of the periodic table. When the separator is composed of a polymer, when the polymer has a functional group, the functional group may be in the main chain or in the side chain. The main chain is ester bond, amide bond, ionic bond, van der Waals bond, agostic interaction, hydrogen bond, acetal bond, ketal bond, ether bond, peroxide bond, carbon-carbon bond, carbon-nitrogen bond, carbamate bond. , A thiocarbamate bond, a carbamide bond, a thiocarbamide bond, an oxazoline moiety-containing bond, a triazine bond, and the like.
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. The separator may have pores, micropores, and a gas diffusion layer. When using a water-containing electrolyte, it is preferable to perform a hydrophilic treatment on the separator by introducing a surfactant or the like.

Furthermore, since a water-containing electrolyte can be used as the electrolyte in the battery using the zinc negative electrode of the present invention, a highly safe battery can be obtained. Thus, the battery comprised using the zinc negative electrode, positive electrode, separator, and aqueous electrolyte solution of this invention is also one of this invention. The battery of the present invention may contain one of these essential components, or may contain two or more. Further, the battery of the present invention is particularly preferably a secondary battery, and thereby, the effect of improving the charge / discharge cycle characteristics can be remarkably exhibited. Even if the battery of the present invention is a primary battery, the effect of suppressing self-discharge can be exhibited.

The positive electrode is formed using a positive electrode mixture. The positive electrode mixture includes a positive electrode active material. 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, and are not particularly limited. For example, oxygen (when oxygen becomes a positive electrode active material, the positive electrode is oxygen An air electrode composed of a perovskite type compound, a cobalt-containing compound, an iron-containing compound, a copper-containing compound, a manganese-containing compound, a platinum-containing compound, a gold-containing compound, a carbon-containing compound, etc. And nickel compounds such as nickel oxyhydroxide, nickel hydroxide and cobalt-containing nickel hydroxide, manganese compounds such as manganese dioxide, silver oxide, and iron-containing compounds. Among these, it is a battery using the zinc negative electrode mixture of the present invention, and the positive electrode active material is oxygen, a nickel compound, or a manganese compound, which is also a preferred embodiment of the present invention.
The positive electrode mixture further includes a conductive additive, a compound having at least one element selected from the group consisting of elements belonging to Groups 1 to 17 of the periodic table, an organic compound, an organic compound salt, and the like. Also good. The preferable structure of these components is the same as the preferable structure of these components contained in the said zinc negative electrode mixture.

The electrolyte is not particularly limited as long as it is usually used as a battery electrolyte, and examples thereof include water-containing electrolytes and organic solvent-based electrolytes, and water-containing electrolytes are preferred. The water-containing electrolytic solution refers to an electrolytic solution using only water as an electrolytic solution raw material (aqueous electrolytic solution) or an electrolytic solution using a solution obtained by adding an organic solvent to water as an electrolytic solution raw material. Examples of the aqueous electrolyte include potassium hydroxide aqueous solution, sodium hydroxide aqueous solution, lithium hydroxide aqueous solution, zinc sulfate aqueous solution, zinc nitrate aqueous solution, zinc phosphate aqueous solution, and zinc acetate aqueous solution. Although it does not restrict | limit especially as electrolyte, When using aqueous electrolyte solution, the compound which generate | occur | produces the hydroxide ion which bears ion conduction in a system is preferable. In particular, an aqueous potassium hydroxide solution is preferable from the viewpoint of ion conductivity. The aqueous electrolyte solution can be used alone or in combination of two or more. Moreover, the said water containing electrolyte solution may contain the organic solvent used for an organic solvent type electrolyte solution. Examples of the organic solvent include ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate, γ-butyrolactone, dimethoxymethane, diethoxymethane, dimethoxyethane, tetrahydrofuran, methyltetrahydrofuran, diethoxyethane, dimethyl sulfoxide, sulfolane, acetonitrile, and benzonitrile. Ionic liquid, fluorine-containing carbonates, fluorine-containing ethers, polyethylene glycols, fluorine-containing polyethylene glycols and the like. The electrolytic solution can be used alone or in combination of two or more.

The concentration of the electrolyte is preferably 0.01 to 20 mol / L. By using the electrolytic solution having such a concentration, good battery performance can be exhibited. Moreover, More preferably, it is 0.1-18 mol / L. Further, the electrolytic solution may contain an additive. As an additive, a compound having at least one element selected from the group consisting of elements belonging to Groups 1 to 17 in the same table other than zinc may be added to the electrolytic solution. One or more additives can be used. For example, in the case of potassium hydroxide electrolyte, magnesium hydroxide, barium hydroxide, calcium hydroxide, magnesium chloride, barium chloride, calcium chloride, potassium fluoride, potassium borate, potassium hydrogen borate, sodium borate, boron Sodium hydrogen phosphate, potassium phosphate, potassium hydrogen phosphate, sodium phosphate, sodium hydrogen phosphate, potassium arsenate, lithium carbonate, potassium carbonate, sodium carbonate, magnesium carbonate, calcium carbonate, barium carbonate, indium hydroxide, silicic acid Potassium, sodium silicate, lithium hydroxide, sodium sulfide, potassium sulfate, sodium sulfate, potassium thiosulfate, sodium thiosulfate, cadmium oxide, cobalt hydroxide, titanium oxide, zirconium oxide, aluminum oxide, lithium oxide, sodium oxide Lithium, lithium hydroxide, sodium hydroxide, magnesium oxide, calcium oxide, barium oxide, bismuth oxide, bismuth hydroxide, zinc hydroxide, lead oxide, lead acetate, tellurium oxide, iron oxide, germanium oxide, tin oxide, hydroxide Tin, tin chloride, indium oxide, lanthanoid oxide, niobium oxide, chromium oxide, copper oxide, gallium oxide, thallium oxide, antimony oxide, saccharides such as sorbitol, quaternary ammonium salt, quaternary phosphonium salt, caprolactam compound, chelate Agent, methanol, ethanol, butanol, carboxylic acid, carboxylate, sulfonic acid, sulfonate, sulfonamide, sulfone, sulfoxide, polymer, gel compound, carboxylate group, and / or sulfonate group, and / or Quaternary ammonium salts, and / or Polymer or gel compound having a quaternary phosphonium salt and the like.

Moreover, as a form of the battery using the zinc negative electrode mixture of the present invention, a primary battery, a secondary battery capable of charging / discharging, use of mechanical charge (mechanical replacement of the zinc negative electrode), a zinc negative electrode of the present invention and Any form such as utilization of a third electrode different from the positive electrode composed of the positive electrode active material as described above may be used.
Below, taking the nickel electrode as an example, the configuration of the nickel-zinc storage battery will be described. The nickel / zinc 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 (Ni-hydrogen storage alloy battery), a nickel * cadmium battery, etc. The inner wall of the assembly and holding container should be made of a material that will not deteriorate due to corrosion, reaction during charging / discharging, etc. 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 at the time of charging / discharging.

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 and the negative electrode current collector are coated with a paste or slurry of a positive electrode material and a paste or slurry of a negative electrode material, respectively, and the coated electrode is dried and compressed, and after cutting and cleaning Then, the cut electrodes and the separator are stacked in layers to form a battery assembly. The dry process is a process using, for example, electrode component powder or a granular dry mixture instead of slurry or paste. (1) The negative electrode material is applied to a current collector, and (2) the positive electrode material is collected in a dry state. (3) A separator is placed between the sheets of (1) and (2) to form a layered structure to form a battery assembly, and (4) the battery assembly of (3) is wound or folded. The three-dimensional structure is formed through the same process. The electrode may be wrapped with a separator or gel electrolyte, 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 battery manufacturing process or storage, the battery may be in a charged state or a discharged state.

The zinc negative electrode mixture of the present invention has the above-described configuration, and when a zinc negative electrode is formed, self-discharge can be particularly suppressed as compared with a conventional zinc negative electrode.

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. Unless otherwise specified, “part” means “part by mass” and “%” means “% by mass”.

Example 1
Zinc oxide (tap density: 1.00 g / mL, crystallite size: 736 mm), 27.6 g, acetylene black (average particle size: about 40 nm, specific surface area: about 70 m ² / g), 0.90 g, cerium oxide (IV) 2.4 g, 92.7 g of ethanol (99.5%, manufactured by Wako Pure Chemical Industries, Ltd.) and 92.7 g of water were added to the ball mill, and ball mill mixing was performed. Then, it dried at 100 degreeC under pressure reduction for 2 hours with the evaporator, and also dried at 110 degreeC under pressure reduction with the stationary type vacuum dryer overnight. The solid after drying was pulverized for 60 seconds at a rotation speed of 18000 rpm using a pulverizer (X-Treme MX1200XTM manufactured by WARING). The obtained solid (1.1 g), 12% polyvinylidene fluoride / N-methylpyrrolidone solution (2.0 g) and N-methylpyrrolidone (0.90 g) were added to a glass vial, and the mixture was stirred overnight with a stirrer using a stirrer bar. The obtained slurry was coated on a copper foil using an automatic coating apparatus and dried at 80 ° C. for 12 hours. The copper foil coated with the zinc mixture was pressed at a press pressure of 3 t. This was punched out with a punching machine (diameter: 15.95 mm) to form a zinc mixture electrode, and the working electrode (zinc mixture weight: 2.47 mg) having an apparent area of 0.48 cm ² was used. A zinc electrode is used for the counter electrode, a zinc wire is used for the reference electrode, and a 4 mol / L potassium hydroxide aqueous solution (dissolved oxygen amount 5.2 mg / L) in which zinc oxide is dissolved is used for the electrolyte. Using the cell, a charge / discharge test was performed at a current value of 1.17 mA (charge / discharge time: 1 hour each / cut off at −0.1 V and 0.4 V). The charge capacity at the 10th cycle was 656 mAh / g. Next, the discharge operation under the same conditions, after the zinc oxide in sub Namarigozai electrodes were all converted to zinc metal, and allowed to stand for 24 hours, was charged operation followed by the same conditions. The discharge capacity at this time was 627 mAh / g, and it was found that self-discharge hardly occurred.

(Example 2)
Zinc oxide (tap density: 0.96 g / mL, crystallite size: 743 mm), 27.6 g, acetylene black (average particle size: about 40 nm, specific surface area: about 70 m ² / g), 0.90 g, cerium oxide (IV) 2.4 g, 92.7 g of ethanol (99.5%, manufactured by Wako Pure Chemical Industries, Ltd.) and 92.7 g of water were added to the ball mill, and ball mill mixing was performed. Thereafter, a zinc mixture electrode was prepared in the same manner as in Example 1 and used so as to have a working electrode having an apparent area of 0.48 cm ² (zinc mixture weight: 3.18 mg). In the same manner as in Example 1, a charge / discharge test was performed using a triode cell at a current value of 1.51 mA (charge / discharge time: 1 hour each). The charge capacity at the 10th cycle was 658 mAh / g. Next, the discharge operation under the same conditions, after the zinc oxide in sub Namarigozai electrodes were all converted to zinc metal, and allowed to stand for 24 hours, was charged operation followed by the same conditions. The discharge capacity at this time was 639 mAh / g, and it was found that self-discharge hardly occurred.

(Example 3)
Zinc oxide (tap density: 0.91 g / mL, crystallite size: 867 ：), 27.6 g, acetylene black (average particle size: about 40 nm, specific surface area: about 70 m ² / g), 0.90 g, cerium oxide (IV) 2.4 g, 92.7 g of ethanol (99.5%, manufactured by Wako Pure Chemical Industries, Ltd.) and 92.7 g of water were added to the ball mill, and ball mill mixing was performed. Thereafter, a zinc mixture electrode was prepared in the same manner as in Example 1 and used so as to have a working electrode (zinc mixture weight: 1.89 mg) having an apparent area of 0.48 cm ² . Similarly to Example 1, a charge / discharge test was conducted using a triode cell at a current value of 0.845 mA (charge / discharge time: 1 hour each). The charge capacity at the 10th cycle was 659 mAh / g. Next, the discharge operation under the same conditions, after the zinc oxide in sub Namarigozai electrodes were all converted to zinc metal, and allowed to stand for 24 hours, was charged operation followed by the same conditions. The discharge capacity at this time was 659 mAh / g, and it was found that self-discharge hardly occurred.

Example 4
Zinc oxide (tap density: 0.88 g / mL, crystallite size: 772 mm), 27.6 g, acetylene black (average particle size: about 40 nm, specific surface area: about 70 m ² / g), 0.90 g, cerium oxide (IV) 2.4 g, 92.7 g of ethanol (99.5%, manufactured by Wako Pure Chemical Industries, Ltd.) and 92.7 g of water were added to the ball mill, and ball mill mixing was performed. Thereafter, a zinc mixture electrode was prepared in the same manner as in Example 1 and used so as to have a working electrode (zinc mixture weight: 1.62 mg) having an apparent area of 0.48 cm ² . Similarly to Example 1, a charge / discharge test was conducted using a triode cell at a current value of 0.768 mA (charge / discharge time: 1 hour each). The charge capacity at the 10th cycle was 656 mAh / g. Next, the discharge operation under the same conditions, after the zinc oxide in sub Namarigozai electrodes were all converted to zinc metal, and allowed to stand for 24 hours, was charged operation followed by the same conditions. The discharge capacity at this time was 616 mAh / g, and it was found that self-discharge hardly occurred.

(Example 5)
Zinc oxide (tap density: 0.86 g / mL, crystallite size: 627 mm), 27.6 g, acetylene black (average particle size: about 40 nm, specific surface area: about 70 m ² / g), 0.90 g, cerium oxide (IV) 2.4 g, 92.7 g of ethanol (99.5%, manufactured by Wako Pure Chemical Industries, Ltd.) and 92.7 g of water were added to the ball mill, and ball mill mixing was performed. Thereafter, a zinc mixture electrode was prepared in the same manner as in Example 1 and used so as to have a working electrode having an apparent area of 0.48 cm ² (zinc mixture weight: 2.70 mg). Similarly to Example 1, a charge / discharge test was performed using a triode cell at a current value of 1.28 mA (charge / discharge time: 1 hour each). The charge capacity at the 10th cycle was 652 mAh / g. Next, the discharge operation under the same conditions, after the zinc oxide in sub Namarigozai electrodes were all converted to zinc metal, and allowed to stand for 24 hours, was charged operation followed by the same conditions. The discharge capacity at this time was 623 mAh / g, and it was found that self-discharge hardly occurred.

(Example 6)
Zinc oxide (tap density: 0.83 g / mL, crystallite size: 763 ：) 27.6 g, acetylene black (average particle size: about 40 nm, specific surface area: about 70 m ² / g) 0.90 g, cerium oxide (IV) 2.4 g, 92.7 g of ethanol (99.5%, manufactured by Wako Pure Chemical Industries, Ltd.) and 92.7 g of water were added to the ball mill, and ball mill mixing was performed. Thereafter, a zinc mixture electrode was prepared in the same manner as in Example 1 and used so as to be a working electrode having an apparent area of 0.48 cm ² (zinc mixture weight: 2.36 mg). Similarly to Example 1, a charge / discharge test was performed using a triode cell at a current value of 1.12 mA (charge / discharge time: 1 hour each). The charge capacity at the 10th cycle was 655 mAh / g. Next, the discharge operation under the same conditions, after the zinc oxide in sub Namarigozai electrodes were all converted to zinc metal, and allowed to stand for 24 hours, was charged operation followed by the same conditions. The discharge capacity at this time was 630 mAh / g, and it was found that self-discharge hardly occurred.

(Example 7)
Zinc oxide (tap density: 0.82 g / mL, crystallite size: 647 mm), 27.6 g, acetylene black (average particle size: about 40 nm, specific surface area: about 70 m ² / g), 0.90 g, cerium oxide (IV) 2.4 g, 92.7 g of ethanol (99.5%, manufactured by Wako Pure Chemical Industries, Ltd.) and 92.7 g of water were added to the ball mill, and ball mill mixing was performed. Thereafter, a zinc mixture electrode was prepared in the same manner as in Example 1 and used so as to have a working electrode having an apparent area of 0.48 cm ² (zinc mixture weight: 2.43 mg). Similarly to Example 1, a charge / discharge test was performed using a triode cell at a current value of 1.15 mA (charge / discharge time: 1 hour each). The charge capacity at the 10th cycle was 658 mAh / g. Next, the discharge operation under the same conditions, after the zinc oxide in sub Namarigozai electrodes were all converted to zinc metal, and allowed to stand for 24 hours, was charged operation followed by the same conditions. The discharge capacity at this time was 629 mAh / g, and it was found that self-discharge hardly occurred.

(Example 8)
Zinc oxide (tap density: 0.78 g / mL, crystallite size: 741 ：) 27.6 g, acetylene black (average particle size: about 40 nm, specific surface area: about 70 m ² / g) 0.90 g, cerium oxide (IV) 2.4 g, 92.7 g of ethanol (99.5%, manufactured by Wako Pure Chemical Industries, Ltd.) and 92.7 g of water were added to the ball mill, and ball mill mixing was performed. Thereafter, a zinc mixture electrode was prepared in the same manner as in Example 1 and used so as to be a working electrode having an apparent area of 0.48 cm ² (zinc mixture weight: 2.32 mg). Similarly to Example 1, a charge / discharge test was performed using a triode cell at a current value of 1.10 mA (charge / discharge time: 1 hour each). The charge capacity at the 10th cycle was 648 mAh / g. Next, the discharge operation under the same conditions, after the zinc oxide in sub Namarigozai electrodes were all converted to zinc metal, and allowed to stand for 24 hours, was charged operation followed by the same conditions. The discharge capacity at this time was 605 mAh / g, and it was found that self-discharge hardly occurred.

(Comparative Example 1)
Zinc oxide (tap density: 0.61 g / mL, crystallite size: 575 mm), 27.6 g, acetylene black (average particle size: about 40 nm, specific surface area: about 70 m ² / g), 0.90 g, cerium oxide (IV) 2.4 g, 92.7 g of ethanol (99.5%, manufactured by Wako Pure Chemical Industries, Ltd.) and 92.7 g of water were added to the ball mill, and ball mill mixing was performed. Thereafter, a zinc mixture electrode was prepared in the same manner as in Example 1 and used so as to be a working electrode (zinc mixture weight: 2.24 mg) having an apparent area of 0.48 cm ² . Similarly to Example 1, a charge / discharge test was performed using a triode cell at a current value of 1.06 mA (charge / discharge time: 1 hour each). The charge capacity at the 10th cycle was 592 mAh / g. Next, the discharge operation under the same conditions, after the zinc oxide in sub Namarigozai electrodes were all converted to zinc metal, and allowed to stand for 24 hours, was charged operation followed by the same conditions. The discharge capacity at this time was 0 mAh / g, and it was found that self-discharge occurred.

(Comparative Example 2)
Zinc oxide (tap density: 0.76 g / mL, crystallite size: 522 mm), 27.6 g, acetylene black (average particle size: about 40 nm, specific surface area: about 70 m ² / g), 0.90 g, cerium oxide (IV) 2.4 g, 92.7 g of ethanol (99.5%, manufactured by Wako Pure Chemical Industries, Ltd.) and 92.7 g of water were added to the ball mill, and ball mill mixing was performed. Thereafter, a zinc mixture electrode was prepared in the same manner as in Example 1 and used so as to be a working electrode having an apparent area of 0.48 cm ² (zinc mixture weight: 2.66 mg). Similarly to Example 1, a charge / discharge test was performed using a triode cell at a current value of 1.27 mA (charge / discharge time: 1 hour each). The charge capacity at the 10th cycle was 634 mAh / g. Next, the discharge operation under the same conditions, after the zinc oxide in sub Namarigozai electrodes were all converted to zinc metal, and allowed to stand for 24 hours, was charged operation followed by the same conditions. The discharge capacity at this time was 350 mAh / g, and it was found that self-discharge occurred.

The following was found from the results of the examples.
Using a zinc negative electrode mixture containing zinc oxide having a particle tap density of 0.77 g / mL or more and / or zinc oxide having a crystallite diameter of 600 mm or more in the particles, a zinc negative electrode mixture It was proved that the storage battery formed using the negative electrode and formed by using the negative electrode was excellent in charge / discharge cycle characteristics of the battery, even when repeated charge / discharge was repeated. It was also demonstrated that self-discharge can be suppressed. Even in the primary battery, the effect of suppressing self-discharge can be exhibited.

In addition, in the said Example, although the zinc negative electrode was formed using the zinc negative electrode mixture containing the particle | grains of specific zinc oxide, the zinc negative electrode was prepared using the zinc negative electrode mixture of this invention as a zinc negative electrode mixture. By forming the battery, the battery configured using such a zinc negative electrode can stably express high capacity and high energy density, and suppress self-discharge. The mechanism capable of improving the cycle characteristics is the same when the zinc negative electrode mixture of the present invention is used. Therefore, it can be said from the results of the above-described embodiments that the present invention can be applied in the entire technical scope of the present invention and in various forms disclosed in this specification, and can exhibit advantageous effects.

Claims (3)

A zinc negative electrode mixture containing zinc oxide,
The zinc oxide has a particle tap density of 0.77 g / mL or more and 1.00 g / mL or less, and a crystallite having a crystallite diameter of 600 to 1500 mm is present in the particles. Zinc negative electrode mixture. A zinc negative electrode formed using the zinc negative electrode mixture according to claim 1 . A battery comprising the zinc negative electrode according to claim 2 , a positive electrode, and an aqueous electrolyte.