JP2003297347A - Alkaline zinc battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an alkaline zinc battery capable of suppressing generation of hydrogen gas at the surface of its negative electrode, suppressing a deposition of zinc in a dendritic form or sponge form at the negative electrode, and excellent in the anti-leak characteristic and cyclic lifetime. <P>SOLUTION: The alkaline zinc battery is composed of the negative electrode containing zinc or zinc alloy as its active material, a positive electrode, a separator, and alkali electrolytic solution, wherein a cationic organic substance is arranged in the neighborhood of the surface of the negative electrode. Because of arrangement of the cationic organic substance in the neighborhood of the negative electrode surface, cationic functional groups existing near the electrode of the negative electrode surface are adsorbed electrostatically to the reaction activating point on the negative electrode, and thereby the potential is smoothened, and a deposition and growth of zinc in a dendritic form or sponge form at the negative electrode are suppressed, and also generation of hydrogen gas is suppressed. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an alkaline zinc battery containing zinc or a zinc compound in a negative electrode, and more particularly to an alkaline zinc battery having excellent leakage resistance in which generation of hydrogen gas on the surface of the negative electrode is suppressed.

[0002]

2. Description of the Related Art Alkali-zinc secondary batteries using zinc or zinc alloy as a negative electrode active material have high energy density and are effective in reducing the size and weight of electronic devices in recent years. -Various studies have been conducted on zinc secondary batteries and the like. In particular, the nickel-zinc secondary battery has a higher energy density and is cheaper than the nickel-cadmium secondary battery and the nickel-hydrogen secondary battery, and in addition, a harmful material such as cadmium is not used. Since it has the advantage of low pollution, great expectations are placed on its practical application.

However, in an alkaline zinc secondary battery using zinc as a negative electrode active material, as in a manganese dry battery or an alkaline primary battery, a corrosive reaction accompanied by hydrogen generation occurs drastically in the zinc negative electrode during storage, and the internal pressure of the battery rises. There is a problem that the battery expands and leaks. It is known that the amalgamation of zinc negative electrode with mercury is effective for suppressing the corrosion reaction of zinc. There is a strong demand for technology. Therefore, the use of zinc alloys, inorganic inhibitors, organic inhibitors, etc. in place of mercury has been studied.

For example, elements such as indium and bismuth are known as materials having a high hydrogen overvoltage.
In JP 66, these compounds are used as inorganic inhibitors.

As the organic inhibitor, amine, diethanolamine, oleic acid, lauryl ether, or ethylene oxide polymer has been proposed. Then, as an example of the composite addition of an inorganic inhibitor and an organic inhibitor, JP-A-2-79367 proposes the composite addition of indium hydroxide and an ethoxyfluoroalcohol-based polyfluorinated compound.

Further, in the alkaline zinc secondary battery, in addition to gas generation due to zinc corrosion during storage, hydrogen gas generation due to reduction reaction of water molecules on the surface of the zinc negative electrode during overcharge causes an increase in battery internal pressure. This may cause the battery to expand, burst, or leak. Therefore, in order to suppress generation of hydrogen gas due to overcharge of the zinc negative electrode, the alkaline secondary battery is generally designed to regulate the positive electrode capacity.

In the alkaline zinc secondary battery, the reaction product at the time of discharging is soluble in the alkaline electrolyte, so that the zinc negative electrode is repeatedly dissolved and deposited during charging and discharging. Therefore, during charging, zinc deposits on the surface of the negative electrode in a dendritic or spongy form, and as they repeat charging and discharging, they grow and penetrate the insulating separator to reach the positive electrode, causing an internal short circuit and shortening the cycle life. There is a problem to let.

In order to prevent such an internal short circuit, in Japanese Patent Laid-Open No. 163963/1982, a porous layer composed of a magnesium oxide layer is formed in close contact with the surface of a zinc negative electrode to prevent zincate ion from being dissolved in an electrolytic solution. Studies have been conducted to prevent elution and suppress dendrite growth. Also,
Japanese Unexamined Patent Publication No. 6-203819 proposes that an insulating separator contains a polymer having a quaternary ammonium group to suppress dendritic or spongy growth of zinc to prevent an internal short circuit. There is.

[0009]

However, in a negative electrode using a corrosion-resistant zinc alloy to which an additional element such as indium or bismuth is added, the zinc corrosion reaction is suppressed in the initial stage of use, but the indium is not generated in the precipitation reaction accompanying charging. , Additional elements such as bismuth do not precipitate uniformly with zinc,
Since the corrosion inhibition effect decreases due to the change in the alloy composition of the corrosion resistant zinc alloy, it is impossible to secure the liquid leakage resistance. Further, the zinc alloy alone cannot control the zinc precipitation morphology, so that it is not possible to prevent an internal short circuit due to repeated charging and discharging.

Also in a battery in which a compound such as indium or bismuth is added as an inorganic inhibitor, it is not possible to secure liquid leakage resistance and prevent internal short-circuiting, as in the case of using a corrosion resistant zinc alloy for the negative electrode. Can not.

Further, in the conventional battery to which an organic inhibitor is added and the battery to which an inorganic inhibitor is added in combination,
Although some effects can be expected, securing the leakage resistance and preventing internal short-circuiting are not practically sufficient.

In addition, in the alkaline zinc secondary battery, the negative electrode is prevented from being overcharged by designing the capacity to regulate the positive electrode, but the distribution of the current density during charging and discharging is not uniform inside the actual battery. However, an overcharged state of the negative electrode may occur at a place where the current density is high. In particular, in a battery with advanced charging / discharging cycle, the non-uniformity of the current density distribution is further increased and hydrogen gas generation due to the overcharged state of the negative electrode is increased, so that the liquid leakage resistance cannot be secured.

Further, a method of preventing the elution of zincate ions into the electrolytic solution by closely forming a porous layer composed of a magnesium oxide layer on the surface of the zinc negative electrode is to adsorb and fix zincate ions to grow zinc dendrite. This is a technique to prevent, but in this technique, the deposition form of zinc itself from zincate ions is dendritic or spongy,
Zinc dendrite growth cannot be sufficiently suppressed when a charge / discharge cycle, especially deep charge / discharge is repeated.
In addition, with this method, the effect of suppressing the generation of hydrogen gas is not sufficient.

Further, in the method of suppressing the resinous or spongy growth of zinc by preventing the internal short circuit by containing the polymer having the quaternary ammonium group in the insulating separator, the zinc dendrite growth is achieved until the separator is reached. Therefore, it is impossible to prevent the capacity decrease due to the drop of zinc dendrite from the negative electrode. Further, it is not possible to prevent deterioration of battery performance due to clogging of the separator. In addition, hydrogen gas generation on the surface of the zinc negative electrode cannot be suppressed, and hydrogen gas generation also occurs from the zinc dendrite.

Therefore, the present invention was devised in view of the above-mentioned conventional circumstances, and the generation of hydrogen gas on the surface of the negative electrode was suppressed, and the deposition of dendritic or spongy zinc on the negative electrode was suppressed. Another object of the present invention is to provide an alkaline zinc battery having excellent liquid leakage resistance and cycle life.

[0016]

An alkaline zinc battery according to the present invention, which achieves the above object, comprises a negative electrode containing zinc or a zinc alloy as a negative electrode active material, a positive electrode, a separator, and an alkaline electrolyte. An alkaline zinc battery obtained by the above, wherein a cationic organic substance is arranged in the vicinity of the surface of the negative electrode.

In the alkaline zinc battery according to the present invention, since the cationic organic substance is arranged in the vicinity of the surface of the negative electrode, the cationic functional group in the vicinity of the surface of the negative electrode is electrostatically adsorbed at the reaction active point of the negative electrode. As a result, the potential is smoothed, the deposition and growth of dendritic or spongy zinc in the negative electrode is suppressed, and the generation of hydrogen gas is also suppressed.

This makes it possible to maintain a good capacity and prevent the battery internal pressure from rising due to the generation of hydrogen gas to cause the battery to expand or leak. In addition, it is possible to prevent the internal short circuit from being caused by the growth of dendritic or spongy zinc on the surface of the negative electrode, which penetrates the insulating separator to reach the positive electrode. Therefore, even when the charge / discharge cycle is repeated in the alkaline zinc secondary battery, it is possible to prevent the occurrence of an internal short circuit due to the growth of dendritic or spongy zinc on the negative electrode surface, and improve the cycle life. Can be made.

Further, in the alkaline zinc battery, it is preferable that the cationic organic substance is one or more of a quaternary ammonium salt, a quaternary phosphonium salt and a tertiary sulfonium salt.

As a method for disposing these cationic organic substances near the surface of the zinc negative electrode, the cationic organic substances are introduced into the side chains of the polymer compound as cationic functional groups near the surface of the negative electrode. It is preferably arranged. That is, it is preferable that the cationic organic substance is introduced as a side chain of the polymer compound as a cationic functional group and the negative electrode is coated with the polymer compound, so that the cationic organic substance is surely disposed in the vicinity of the surface of the negative electrode.

Here, the kinds of cationic functional groups introduced as side chains into the polymer compound include trimethylammonium group, dimethylethylammonium group, methyldiethylammonium group, triethylammonium group, trimethylphosphonium group and dimethylethylphosphonium group. , Methyldiethylphosphonium group, triethylphosphonium group, dimethylsulfonium group, methylethylsulfonium group, diethylsulfonium group and the like,
Of these, it is preferable to introduce one or more as a side chain.

The polymer compound is preferably a polymer of styrene or a copolymer of styrene and divinylbenzene.

The average molecular weight of the polymer compound is preferably 1,000 to 100,000, more preferably 5,000 to 50,000.

The thickness of the negative electrode surface coating film of the polymer compound is preferably 1 μm to 500 μm,
A more preferable thickness of the coating is 10 μm to 100 μm.

Although the mechanism of the effect of the arrangement of the cationic organic substance in the present invention as described above is not clear, it is presumed as follows.

At the time of discharging, in the zinc negative electrode, zinc becomes zincate ions and is eluted / diffused in the electrolytic solution, and a part is deposited as zinc oxide, but the deposition site is not always near the elution site. . Since the reaction of zincate ions to zinc oxide occurs thermodynamically, it can basically occur at any place.

When the battery is charged in this state, the dissolved zincate ions are deposited as metallic zinc on the negative electrode, the zinc oxide deposited during discharge is also dissolved again to form zincate ions, and part is deposited as metal. To do. At that time, the electrons flowing into the zinc negative electrode concentrate at the so-called reaction active point where current is likely to concentrate, such as the surface protrusion of the zinc negative electrode. This causes the generation of hydrogen gas. As a result, the zinc deposition morphology, even microscopically, becomes dendritic or spongy, which is significantly different from the initial surface shape, and also causes a shape change of the electrode from a global perspective, causing an internal short circuit,
In addition to causing capacity deterioration, the generated hydrogen gas raises the internal pressure of the battery, which may cause electrolyte leakage and battery deformation / rupture.

On the other hand, when the method of the present invention is used,
The polymer compound that coats the surface of the zinc negative electrode functions as an anion exchange membrane and does not pass zinc ions as cations as well as large complex ions such as zincate ions. The acid concentration quickly becomes saturated and zinc oxide is produced. On the other hand, since hydroxide ions and water molecules can pass through this film, they do not interfere with the basic battery reaction.

When charging is carried out in such a state, zincate ions and zinc oxide generated by the discharge will be deposited as metallic zinc in the vicinity of the elution site as a whole, so that the shape of the electrode will be greatly changed. There is nothing to do. Also,
Microscopically, the cationic functional group in the immediate vicinity of the surface of the zinc negative electrode is electrostatically adsorbed at the reaction active point, and consequently contributes to the smoothing of the potential, which is not effective. Even if some degree of dendritic deposition occurs in a sufficient portion, the growth of the dendritic deposition is hindered by contact with the cationic functional group, and the separator is not penetrated.

Similarly, the adsorption of the cationic functional group at the reaction active site also suppresses the generation of hydrogen gas.

For the above reason, the cationic functional group is preferably a positively charged molecule such as an ammonium group, a phosphonium group or a sulfonium group, but the hydrogen atom bonded to the hetero atom in the above cationic organic substance is a zinc negative electrode surface. In order to accelerate the hydrogen gas generation by receiving the reduction reaction,
A quaternary ammonium salt, a quaternary phosphonium salt, and a tertiary sulfonium salt in which a hydrogen atom is not bonded to a hetero atom are preferable.

If the coating thickness of the zinc negative electrode with such a polymer compound having a cationic functional group introduced is too thin, no effect will be obtained, and if it is too thick, the battery performance will deteriorate. Further, in order for the cationic functional group to be effectively adsorbed on the surface of the zinc negative electrode, it is necessary for the hetero atom having a positive charge and the surface of the zinc negative electrode to be close to each other. Therefore, the substituent bonded to the hetero atom of the cationic functional group is It is preferable that the carbon number is 2 or less. For example, when a phenyl group is introduced as a substituent, a good zinc deposition form cannot be obtained. It is considered that this is because the bulkiness hinders the precipitation of zinc more than necessary.

[0033]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the alkaline zinc battery according to the present invention will be described in detail below. It should be noted that the present invention is not limited to the following description, and can be appropriately modified without departing from the gist of the present invention.

The alkaline zinc battery according to the present invention is an alkaline zinc battery comprising a negative electrode containing zinc or a zinc alloy as a negative electrode active material, a positive electrode, a separator, and an alkaline electrolyte. It is characterized by arranging a cationic organic substance in the vicinity.

FIG. 1 is a vertical sectional view of an alkaline zinc secondary battery constructed by applying the present invention. In FIG. 1, 1 is a positive electrode can, 2 is a negative electrode lid, 3 is an insulating packing, 4 is an insulating separator, 5 is a positive electrode, 6 is a positive electrode current collector, 7 is a negative electrode, 8 is a negative electrode current collector, and 9 is a positive electrode lead. The wire 10 is a negative electrode lead wire.

The alkaline zinc secondary battery shown in FIG. 1 is an alkaline zinc secondary battery having a structure called a jelly roll type, in which a positive electrode 5 and a negative electrode 6 facing each other with a separator 4 in between are spirally wound. It is loaded in the positive electrode can 1. Regarding the electrical conduction between each electrode and the exterior member, the positive electrode 5 is electrically conducted to the positive electrode can 1 through the positive electrode lead wire 9 welded to the positive electrode 5, and the negative electrode 7 is welded to the negative electrode 7. Also, electrical connection is established with the negative electrode lid 2 via the negative electrode lead wire 10. Further, the battery is sealed by fitting the insulating packing 3 into the opening of the positive electrode can 1, placing the negative electrode lid 2 thereon, and caulking the closed end of the positive electrode can 1 inward.

Next, the main constituent members of the alkaline zinc secondary battery will be described in more detail.

The positive electrode 5 is mainly composed of a positive electrode active material and a conductive agent. A binder such as polytetrafluoroethylene (PTFE) may be added to the positive electrode 5 in order to improve the electrode strength. As the positive electrode active material, any conventionally known material may be used as long as it can be used in an alkaline zinc secondary battery, and examples thereof include nickel oxyhydroxide, silver oxide, manganese dioxide and oxygen.

The conductive agent contained in the positive electrode is, for example, an inorganic conductive agent such as metallic cobalt or cobalt oxide, carbon black such as furnace black, acetylene black or thermal black, or scaly or fibrous natural graphite or artificial graphite. The carbon material conductive agent can be mentioned.

Such a positive electrode can be produced, for example, by mixing a positive electrode active material, a conductive agent, and an electrolytic solution, applying the mixture on a current collector such as foam nickel, and press-molding. it can.

The negative electrode 7 may be any conventionally known negative electrode as long as it is a negative electrode containing at least zinc and a zinc alloy as an active material. As such a negative electrode, for example, zinc powder, zinc oxide, zinc hydroxide or the like is mixed with water in which a binder such as carboxymethyl cellulose is dissolved,
A negative electrode prepared by a paste method of filling, molding, and electrolyzing an active material support such as a current collector, or a negative electrode prepared by a sintering method of sintering zinc powder or a zinc compound in an inert atmosphere can be used. .

Here, the negative electrode 7 is covered with a polymer compound having a side chain containing a cationic organic substance as a cationic functional group. That is, a cationic organic substance is arranged near the surface of the negative electrode 7. Here, the vicinity of the surface of the negative electrode 7 means the degree of a gap between the negative electrode and the insulating separator, and for example, the negative electrode 7 is made of a polymer compound in which a cationic organic substance is introduced into the side chain as a cationic functional group. When the surface of the negative electrode 7 is coated with a cationic organic substance in the vicinity of the surface of the negative electrode 7, the thickness is about 500 μm from the surface of the negative electrode 7.

In this alkaline zinc secondary battery, since the cationic organic substance is disposed near the surface of the negative electrode 7, the cationic functional group located in the immediate vicinity of the surface of the negative electrode 7 is electrostatically attached to the reaction active point of the negative electrode 7. By adsorbing, the electric potential can be smoothed.

Further, the cationic functional groups are adsorbed on the reaction active points of the negative electrode 7 to prevent the deposition of dendritic or spongy zinc on the negative electrode 7. Then, due to variations in the distribution of the cationic organic matter, the effect of preventing zinc deposition becomes insufficient, and even when dendritic or spongy zinc deposition occurs, the cationic organic matter in the vicinity of that while growing to some extent Since they come into contact with each other, it is possible to prevent the growth of dendritic or spongy zinc. As a result, in this alkaline zinc secondary battery, it is possible to prevent the grown dendritic or spongy zinc from penetrating the insulating separator 4 and reaching the positive electrode 5 to cause an internal short circuit. Therefore, in this alkaline zinc secondary battery, it is possible to prevent the occurrence of internal short circuit due to the growth of dendritic or spongy zinc on the negative electrode surface even when the charge and discharge cycle is repeated,
The cycle life can be improved.

Further, since the cationic functional group is adsorbed on the reaction active points of the negative electrode 7, hydrogen gas is generated due to zinc corrosion during storage and hydrogen gas accompanying the reduction reaction of water molecules on the surface of the negative electrode 7 during overcharge. Can be suppressed. As a result, in this alkaline zinc secondary battery, it is possible to prevent the internal pressure of the battery from rising due to the generation of hydrogen gas and causing the battery to expand or leak.

Therefore, in this alkaline zinc secondary battery, it is possible to realize a high quality alkaline zinc secondary battery which has excellent liquid leakage resistance and cycle life while maintaining a good capacity.

As described above, in this alkaline zinc secondary battery, the cationic organic substance is introduced as a cationic functional group into the side chain of the polymer compound, and the negative electrode 7 is coated with the polymer compound film. A cationic organic substance is arranged near the surface of the negative electrode 7. By adopting such a form, the cationic organic substance can be surely arranged in the vicinity of the surface of the negative electrode, and the above-mentioned effect can be surely obtained.

Here, the cationic organic substance is preferably one or more of a quaternary ammonium salt, a quaternary phosphonium salt, and a tertiary sulfonium salt. By arranging these salts as the above-mentioned cationic organic matter in the vicinity of the negative electrode 7, the cationic organic matter can be surely adsorbed on the surface of the negative electrode 7 and is effective without promoting generation of hydrogen on the surface of the negative electrode 7. The effects described above can be obtained.

The types of cationic functional groups introduced as side chains into the polymer compound include trimethylammonium group, dimethylethylammonium group, methyldiethylammonium group, triethylammonium group, trimethylphosphonium group, dimethylethylphosphonium group,
A methyldiethylphosphonium group, a triethylphosphonium group, a dimethylsulfonium group, a methylethylsulfonium group, a diethylsulfonium group and the like are preferable, and it is preferable to introduce at least one of them as a side chain.

As the cationic functional group, those having a substituent such as a fluorinated alkyl group are also preferable because they have high alkali resistance.

The polymer compound is preferably a polymer of styrene or a copolymer of styrene and divinylbenzene. Since these polymers or copolymers have good alkali resistance and heat resistance, by using them as the polymer compound, the effect of the present invention can be reliably obtained for a long period of time. However, in the present invention, the polymer compound is not limited to these, alkali resistance,
Any material can be used as long as it has good heat resistance and the like.

The average molecular weight of the polymer compound is preferably 1,000 to 100,000, more preferably 5,000 to 50,000. When the average molecular weight is lower than 1000, it is difficult to maintain the physical strength of the coating film, and there is a possibility that the coating cannot function reliably. Further, when the average molecular weight is higher than 100,000, the physical strength becomes too high and it becomes rigid, so that there is a possibility that workability may be a problem such that the coating operation cannot be performed smoothly.

The thickness of the negative electrode surface coating film of the polymer compound is preferably 1 μm to 500 μm,
A more preferable thickness of the coating is 10 μm to 100 μm. The thickness of the negative electrode surface coating of the polymer compound is 1 μm
If the thickness is less than m, the effect of the present invention may not be sufficiently exhibited. Further, when the thickness of the negative electrode surface coating film of the polymer compound is more than 500 μm, the battery performance may be adversely affected such as deterioration of load characteristics. Therefore, the thickness of the negative electrode surface coating of the polymer compound is set to 1 μm to 500 μm.
By setting the thickness in the range of μm, the effect of the present invention can be reliably obtained without adversely affecting the battery characteristics.

As the positive electrode current collector 6 and the negative electrode current collector 8, all conventionally known current collectors can be applied as long as they have high conductivity and high hydrogen overvoltage. For example, a copper or nickel mesh or a punching metal plated with tin may be used.

As the insulating separator 4, any conventionally known material may be used as long as it has alkali resistance and mechanical strength to some extent, and has large electric resistance and good liquid retention. I don't care. For example, a thin film of synthetic resin having fine pores such as polyvinyl alcohol crosslinked with nylon, polypropylene, dicarboxylic acid, or the like, woven or non-woven fabric woven of these fibers, cellulose fiber, glass fiber, or the like can be given. Further, it may be a laminated body of a plurality of these kinds or the same kind.

As the alkaline electrolyte, a general potassium hydroxide aqueous solution can be used. For example, when a nickel electrode is used for the positive electrode, it is 20% by weight or more and 40% by weight or more.
It is preferable that the concentration is not more than weight%. Further, since additives such as lithium hydroxide which are usually added for improving the positive electrode performance do not adversely affect the effects of the present invention, they may be appropriately added as necessary.

In the above description, the jelly roll type alkaline zinc secondary battery has been described as an example, but the configuration of the alkaline zinc secondary battery according to the present invention is not limited to this, and for example, an electrode may be used. It is possible to adopt various configurations such as a gum battery type system in which separators are laminated without being wound. Even in this case, the same effect as described above can be obtained.

In the above description, the alkaline zinc secondary battery has been described as an example, but the application of the present invention is not limited to the alkaline zinc secondary battery, and the present invention is also applicable to the alkaline zinc primary battery. Is possible. By applying the present invention to an alkaline zinc primary battery, it is possible to obtain the same effects as above. That is, it is possible to realize a high-quality alkaline zinc primary battery that maintains excellent capacity and is excellent in liquid leakage resistance. Also in the case of the alkaline zinc primary battery, the structure of the battery is not particularly limited, and the battery can be applied to batteries having various structures such as a coin type battery.

[0059]

EXAMPLES The present invention will be described below in more detail based on specific examples, but the present invention is not limited to the following description.

First, in the case where the negative electrode surface of the alkaline zinc secondary battery is coated with a polymer compound having a cationic organic group introduced into the side chain as a cationic functional group, the effect of suppressing liquid leakage and internal short circuit depending on the coating conditions. The battery characteristics were examined.

[Sample 1] In Sample 1, an alkaline zinc secondary battery was prepared as follows.

[0062]Fabrication of positive electrode First, 80 weight of nickel oxyhydroxide, which is the positive electrode active material
Parts, 1 part by weight of calcium hydroxide, 10 parts by weight of graphite powder
Parts and mix in a Raira mortar for 30 minutes to obtain a mixture.
It was Next, the polytetrafluoroethylene was added to this mixture.
2 parts by weight of a 3% aqueous solution of carboxymethyl cellulose
Add 10 parts by weight and stir until uniform to obtain a slurry.
It was Then, add the foamed nickel as a current collector to this slurry.
And then pull it up and dry at a temperature of 120 ° C for 12 hours.
It was dried and rolled under a linear pressure of 2 tons to obtain a positive electrode.

[0063]Fabrication of negative electrode First, a zinc alloy powder (Al: 50 pp) that is a negative electrode active material.
m, Bi: 100 ppm, In: 500 ppm) 70 layers
Parts, 35 parts by weight of zinc oxide powder, and polytetrafluor
Mix 2 parts by weight of polyethylene in a raft mortar for 30 minutes
A mixture was obtained. Next, add carboxymeme to this mixture.
Add 10 parts by weight of 3% aqueous solution of chill cellulose and homogenize
It was stirred until it became a slurry. And this slurry
The copper punching metal as a current collector,
It is dried at a temperature of 20 ℃ for 12 hours and rolled at a linear pressure of 2 tons.
It was

Further, as a zinc powder-coated polymer compound for coating the negative electrode, it was immersed in a 2% toluene solution of a styrene polymer having an average molecular weight of 10,000 and trimethylammonium chloride introduced as a cationic functional group, and then pulled up at a temperature of 120 ° C. After drying for 2 hours, a negative electrode was obtained.

Here, the average coating thickness of the zinc powder-coated polymer compound on the negative electrode, that is, the coating film thickness is 100 μm.
Met. The average coating thickness is obtained by immersing a zinc plate of known weight in the above-mentioned toluene solution of the zinc-coated polymer compound, pulling it up, drying it at a temperature of 120 ° C. for 2 hours, and then weighing it and measuring the coating area in advance. It was determined by comparison with these values.

[0066]Battery assembly The positive electrode produced above is 40 mm long and 70 mm wide.
Welded nickel lead to the end after cutting into
did. In addition, the negative electrode produced above was
After cutting it out to a width of 80 mm, add copper leads to its ends.
Welded. And cut out to 42mm in length and 80mm in width
Non-woven vinylon rayon as a bipolar separator
The positive electrode, the separator, and the negative electrode are laminated in the form of being placed between
To form a laminated body, and wind the laminated body to form a spiral shape.
An electrode element was obtained by shaping.

Next, the negative electrode lead wire is welded to the negative electrode lid, the battery element is inserted into the positive electrode can in which the polypropylene packing is inserted, 3 g of the electrolytic solution is injected, and the opening of the positive electrode can is caulked inside. Thus, an alkaline zinc secondary battery of Sample 1 was obtained. Here, a 39 wt% potassium hydroxide aqueous solution was used as the electrolytic solution. Further, in this battery, in order to regulate the battery capacity by the positive electrode capacity, the electrochemical capacity ratio between the positive electrode and the negative electrode was set to 1: 1.5. Further, the porosity in the battery can was set to 5% by volume.

[Sample 2] An alkaline zinc secondary battery of Sample 2 was prepared in the same manner as Sample 1 except that the styrene polymer used for the zinc-coated polymer compound had an average molecular weight of 1,000. The average coating thickness of the zinc powder-coated polymer compound on the negative electrode, which was determined in the same manner as in Sample 1, was 100 μm.

[Sample 3] An alkaline zinc secondary battery of Sample 3 was prepared in the same manner as Sample 1, except that the styrene polymer used for the zinc-coated polymer compound had an average molecular weight of 5000. The average coating thickness of the zinc powder-coated polymer compound on the negative electrode, which was determined in the same manner as in Sample 1, was 100 μm.

[Sample 4] An alkaline zinc secondary battery of Sample 4 was produced in the same manner as in Sample 1, except that the styrene polymer used in the zinc-coated polymer compound had an average molecular weight of 50,000. The average coating thickness of the zinc powder-coated polymer compound on the negative electrode, which was determined in the same manner as in Sample 1, was 100 μm.

[Sample 5] An alkaline zinc secondary battery of Sample 5 was prepared in the same manner as in Sample 1, except that the styrene polymer used in the zinc-coated polymer compound had an average molecular weight of 100,000. The average coating thickness of the zinc powder-coated polymer compound on the negative electrode, which was determined in the same manner as in Sample 1, was 100 μm.

[Sample 6] The same as sample 1 except that the styrene polymer used in the zinc-coated polymer compound had an average molecular weight of 1000 and the concentration of the toluene solution of the styrene polymer was 0.2%. As a result, a sample 6 alkaline zinc secondary battery was produced. The average coating thickness of the zinc powder-coated polymer compound on the negative electrode, which was determined in the same manner as in Sample 1, was 10 μm.

[Sample 7] An alkaline zinc secondary battery of Sample 7 was prepared in the same manner as Sample 6 except that the styrene polymer used as the zinc-coated polymer compound had an average molecular weight of 5000. The average coating thickness of the zinc powder-coated polymer compound on the negative electrode, which was determined in the same manner as in Sample 1, was 10 μm.

[Sample 8] An alkaline zinc secondary battery of Sample 8 was prepared in the same manner as Sample 6 except that the styrene polymer used for the zinc-coated polymer compound had an average molecular weight of 10,000. The average coating thickness of the zinc powder-coated polymer compound on the negative electrode, which was determined in the same manner as in Sample 1, was 10 μm.

[Sample 9] An alkaline zinc secondary battery of Sample 9 was prepared in the same manner as Sample 6 except that the styrene polymer used for the zinc-coated polymer compound had an average molecular weight of 50,000. The average coating thickness of the zinc powder-coated polymer compound on the negative electrode, which was determined in the same manner as in Sample 1, was 10 μm.

[Sample 10] An alkaline zinc secondary battery of Sample 10 was produced in the same manner as Sample 6 except that the styrene polymer used for the zinc-coated polymer compound had an average molecular weight of 100,000. The average coating thickness of the zinc powder-coated polymer compound on the negative electrode, which was determined in the same manner as in Sample 1, was 10 μm.

[Sample 11] The styrene polymer used for the zinc-coated polymer compound had an average molecular weight of 1,000,
Sample 11 was prepared in the same manner as Sample 1 except that the toluene solution concentration of the styrene polymer was 0.02%.
Alkaline zinc secondary battery was manufactured. Also, sample 1
The average coating thickness of the zinc powder-coated polymer compound on the negative electrode, which was determined in the same manner as in 1., was 1 μm.

[Sample 12] An alkaline zinc secondary battery of Sample 12 was produced in the same manner as in Sample 11, except that the styrene polymer used in the zinc-coated polymer compound had an average molecular weight of 5000. The average coating thickness of the zinc powder-coated polymer compound on the negative electrode, which was determined in the same manner as in Sample 1, was 1 μm.

[Sample 13] An alkaline zinc secondary battery of Sample 13 was produced in the same manner as in Sample 11, except that the styrene polymer used for the zinc-coated polymer compound had an average molecular weight of 10,000. The average coating thickness of the zinc powder-coated polymer compound on the negative electrode, which was determined in the same manner as in Sample 1, was 1 μm.

[Sample 14] An alkaline zinc secondary battery of Sample 14 was prepared in the same manner as Sample 11 except that the styrene polymer used for the zinc-coated polymer compound had an average molecular weight of 50,000. The average coating thickness of the zinc powder-coated polymer compound on the negative electrode, which was determined in the same manner as in Sample 1, was 1 μm.

[Sample 15] An alkaline zinc secondary battery of Sample 15 was prepared in the same manner as Sample 11 except that the styrene polymer used for the zinc-coated polymer compound had an average molecular weight of 100,000. The average coating thickness of the zinc powder-coated polymer compound on the negative electrode, which was determined in the same manner as in Sample 1, was 1 μm.

[Sample 16] The average molecular weight of the styrene polymer used for the zinc-coated polymer compound was 1,000,
An alkaline zinc secondary battery of Sample 16 was produced in the same manner as Sample 1 except that the toluene solution concentration of the styrene polymer was 10%. The average coating thickness of the zinc powder-coated polymer compound on the negative electrode, which was determined in the same manner as in Sample 1, was 500 μm.

[Sample 17] An alkaline zinc secondary battery of Sample 17 was produced in the same manner as in Sample 16, except that the styrene polymer used in the zinc-coated polymer compound had an average molecular weight of 5000. The average coating thickness of the zinc powder-coated polymer compound on the negative electrode, which was determined in the same manner as in Sample 1, was 500 μm.

[Sample 18] An alkaline zinc secondary battery of Sample 18 was produced in the same manner as in Sample 16, except that the styrene polymer used in the zinc-coated polymer compound had an average molecular weight of 10,000. The average coating thickness of the zinc powder-coated polymer compound on the negative electrode, which was determined in the same manner as in Sample 1, was 500 μm.

[Sample 19] An alkaline zinc secondary battery of Sample 19 was produced in the same manner as in Sample 16, except that the styrene polymer used in the zinc-coated polymer compound had an average molecular weight of 50,000. The average coating thickness of the zinc powder-coated polymer compound on the negative electrode, which was determined in the same manner as in Sample 1, was 500 μm.

[Sample 20] An alkaline zinc secondary battery of Sample 20 was produced in the same manner as in Sample 16, except that the styrene polymer used in the zinc-coated polymer compound had an average molecular weight of 100,000. The average coating thickness of the zinc powder-coated polymer compound on the negative electrode, which was determined in the same manner as in Sample 1, was 500 μm.

[Sample 21] The same as sample 1 except that the styrene polymer used in the zinc-coated polymer compound had an average molecular weight of 500 and the concentration of the toluene solution of the styrene polymer was 0.002%. Sample 21
Alkaline zinc secondary battery was manufactured. Also, sample 1
The average coating thickness of the zinc powder-coated polymer compound in the negative electrode was 0.1 μm, which was determined in the same manner as in.

[Sample 22] An alkaline zinc secondary battery of Sample 22 was prepared in the same manner as Sample 21, except that the styrene polymer used for the zinc-coated polymer compound had an average molecular weight of 1,000. The average coating thickness of the zinc powder-coated polymer compound on the negative electrode, which was determined in the same manner as in Sample 1, was 0.1 μm.

[Sample 23] An alkaline zinc secondary battery of Sample 23 was prepared in the same manner as Sample 21, except that the styrene polymer used as the zinc-coated polymer compound had an average molecular weight of 5000. The average coating thickness of the zinc powder-coated polymer compound on the negative electrode, which was determined in the same manner as in Sample 1, was 0.1 μm.

[Sample 24] An alkaline zinc secondary battery of Sample 24 was produced in the same manner as in Sample 21, except that the styrene polymer used in the zinc-coated polymer compound had an average molecular weight of 10,000. The average coating thickness of the zinc powder-coated polymer compound on the negative electrode, which was determined in the same manner as in Sample 1, was 0.1 μm.

[Sample 25] The same procedure as in Sample 1 except that the styrene polymer used for the zinc-coated polymer compound had an average molecular weight of 500, and the toluene solution concentration of the styrene polymer was 0.02%. As a result, a sample 25 alkaline zinc secondary battery was produced. The average coating thickness of the zinc powder-coated polymer compound on the negative electrode, which was determined in the same manner as in Sample 1, was 1 μm.

[Sample 26] The average molecular weight of the styrene polymer used for the zinc-coated polymer compound was 500,000, and the toluene solution concentration of the styrene polymer was 0.00.
An alkaline zinc secondary battery of Sample 26 was made in the same manner as Sample 1 except that the content was 2%. The average coating thickness of the zinc powder-coated polymer compound on the negative electrode, which was determined in the same manner as in Sample 1, was 1 μm.

[Sample 27] The same procedure as in Sample 1 except that the styrene polymer used for the zinc-coated polymer compound had an average molecular weight of 500 and the concentration of the toluene solution of the styrene polymer was 0.2%. As a result, a sample 27 alkaline zinc secondary battery was prepared. The average coating thickness of the zinc powder-coated polymer compound on the negative electrode, which was determined in the same manner as in Sample 1, was 10 μm.

[Sample 28] The average molecular weight of the styrene polymer used for the zinc-coated polymer compound was 500,000, and the toluene solution concentration of the styrene polymer was 0.2%.
Sample 2 is the same as Sample 1 except that
No. 8 alkaline zinc secondary battery was produced. The average coating thickness of the zinc powder-coated polymer compound on the negative electrode, which was determined in the same manner as in Sample 1, was 10 μm.

[Sample 29] A sample was prepared in the same manner as in Sample 1 except that the styrene polymer used for the zinc-coated polymer compound had an average molecular weight of 500 and the toluene solution concentration of the styrene polymer was 2%. 29 alkaline zinc secondary batteries were produced. The average coating thickness of the zinc powder-coated polymer compound on the negative electrode, which was determined in the same manner as in Sample 1, was 100 μm.

[Sample 30] A sample was prepared in the same manner as in Sample 1 except that the styrene polymer used for the zinc-coated polymer compound had an average molecular weight of 500,000 and the concentration of the toluene solution of the styrene polymer was 2%. Thirty alkaline zinc secondary batteries were produced. The average coating thickness of the zinc powder-coated polymer compound on the negative electrode, which was determined in the same manner as in Sample 1, was 100 μm.

[Sample 31] The average molecular weight of the styrene polymer used for the zinc-coated polymer compound was 5,000,
An alkaline zinc secondary battery of Sample 31 was produced in the same manner as Sample 1 except that the toluene solution concentration of the styrene polymer was 10%. The average coating thickness of the zinc powder-coated polymer compound on the negative electrode, which was determined in the same manner as in Sample 1, was 500 μm.

[Sample 32] A sample was prepared in the same manner as in Sample 1 except that the styrene polymer used for the zinc-coated polymer compound had an average molecular weight of 500,000 and the toluene solution concentration of the styrene polymer was 10%. 32
Alkaline zinc secondary battery was manufactured. Also, sample 1
The average coating thickness of the zinc powder-coated polymer compound on the negative electrode was 500 μm, which was determined in the same manner as in.

[Sample 33] A sample was prepared in the same manner as in Sample 1 except that the styrene polymer used for the zinc-coated polymer compound had an average molecular weight of 10,000 and the concentration of the toluene solution of the styrene polymer was 20%. 33
Alkaline zinc secondary battery was manufactured. Also, sample 1
The average coating thickness of the zinc powder-coated polymer compound in the negative electrode was 1000 μm, which was determined in the same manner as in.

[Sample 34] A sample was prepared in the same manner as in Sample 1 except that the styrene polymer used for the zinc-coated polymer compound had an average molecular weight of 50,000 and the toluene solution concentration of the styrene polymer was 20%. 34
Alkaline zinc secondary battery was manufactured. Also, sample 1
The average coating thickness of the zinc powder-coated polymer compound in the negative electrode was 1000 μm, which was determined in the same manner as in.

[Sample 35] A sample was prepared in the same manner as in Sample 1 except that the styrene polymer used for the zinc-coated polymer compound had an average molecular weight of 100,000 and the toluene solution concentration of the styrene polymer was 20%. 35
Alkaline zinc secondary battery was manufactured. Also, sample 1
The average coating thickness of the zinc powder-coated polymer compound in the negative electrode was 1000 μm, which was determined in the same manner as in.

[Sample 36] A sample was prepared in the same manner as in Sample 1 except that the styrene polymer used for the zinc-coated polymer compound had an average molecular weight of 500,000 and the toluene solution concentration of the styrene polymer was 20%. 36
Alkaline zinc secondary battery was manufactured. Also, sample 1
The average coating thickness of the zinc powder-coated polymer compound in the negative electrode was 1000 μm, which was determined in the same manner as in.

[Sample 37] An alkaline zinc secondary battery of Sample 37 was produced in the same manner as in Sample 1 except that coating with the zinc-coated polymer compound was not performed.

Regarding the alkaline zinc secondary batteries of Sample 1 to Sample 37 produced as described above, the liquid leakage resistance,
The cycle life and discharge time were evaluated. The cycle life was evaluated by the internal short-circuit rate. Those with a low internal short-circuit rate were evaluated as having a long cycle life, and those with a high internal short-circuit rate were evaluated as having a short cycle life. First, a method for evaluating the leakage resistance of the alkaline zinc secondary battery will be described.

[0105]Leakage resistance evaluation method First, the alkaline zinc secondary batteries of Sample 1 to Sample 37
Prepare 100 ponds for each condition, and replenish each
After the electric cycle, charge the battery at 60 ℃
It was stored for 10 days. After that, liquid leakage was observed by visual inspection.
Leakage from the ratio of the total number of batteries (100)
The rate (%) was calculated. In the charge / discharge cycle, 100
Discharge at constant current of mA until the final voltage reaches 1.0V
At a constant current of 200 mA and a constant voltage of 1.90 V at 10:00
It was charged for a while. And the above steps are considered as one cycle
Then, this process was repeated 20 cycles. as a result
Is shown in Table 1.

Next, a method for evaluating the internal short circuit rate of the alkaline zinc secondary battery will be described below.

[0107]Internal short-circuit rate evaluation method First, the alkaline zinc secondary batteries of Sample 1 to Sample 37
Prepare 100 ponds for each condition, and replenish each
After the electric cycle, charge the battery for 2 hours at room temperature.
The circuit was allowed to stand and the open circuit voltage was measured. In addition, these batteries
After being left at room temperature for an hour, the open circuit voltage was measured again.
And, the voltage drop width (ΔV) before and after left at room temperature for 24 hours is
Number of batteries with 100 mV or more as internal short-circuit batteries
Internal short-circuit rate (%) from the percentage of the total number (100)
I asked. In addition, in the charge / discharge cycle, a constant current of 100 mA
Discharge until the final voltage reaches 1.0 V in a current of 200 m
Charging was performed for 10 hours at A constant current of 1.90V constant voltage.
And, the above process is regarded as one cycle, and this process is divided into 3
The cycle was repeated 0 times. The results are shown in Table 1.

[0108]Discharge time Until the final voltage reaches 1.0V at a constant current of 100mA
Discharged at 200mA constant current 1.90V constant voltage at 10:00
It was charged for a while. And the above steps are considered as one cycle
Then, this step was repeated 30 cycles. At this time
The discharge time of the 30th cycle is defined as the discharge time of this embodiment.
It was The results are shown in Table 1.

[0109]

[Table 1]

First, as can be seen from Table 1, the surface of the negative electrode was
By coating with a polymer compound in which a cationic organic group is introduced into the side chain as a cationic functional group, the effect of improving the liquid leakage rate or the internal short circuit rate is recognized. Then, in Table 1, by comparing Sample 1 to Sample 20 and Sample 21 to Sample 37, the average molecular weight of the zinc-coated polymer compound was 1000 to 1000.
Under the condition of No. 00, when the coating film thickness is 1 μm to 500 μm, sufficient discharge capacity is obtained and liquid leakage,
It can be seen that the internal short circuit is effectively suppressed. Also,
From Table 1, this improvement effect, that is, the effect of suppressing liquid leakage and internal short-circuiting, becomes most remarkable when the coating film thickness is 10 μm to 100 μm under the above-mentioned average molecular weight of 5,000 to 50,000, and sufficient discharge capacity is obtained. It can be seen that, while maintaining the above, a good suppressing effect on liquid leakage and internal short circuit can be obtained.

Although the reason why the above-mentioned improvement effect is exhibited in Samples 1 to 20 is not clear, variations in the improvement effect occur in Samples 21 to 37, resulting in leakage or internal short circuit. The reason why a good result is not obtained with respect to the suppression effect or the discharge time is considered as follows.

First, the actual negative electrode is an aggregate of zinc alloy powder and zinc oxide powder, and when the coating film thickness calculated using a zinc plate is very thin, such as 0.1 μm, the discharge time is Although a sufficient value is obtained, the result is insufficient in the effect of suppressing liquid leakage and internal short circuit. This is because when the coating film thickness on the negative electrode is very thin, such as 0.1 μm, a certain amount of film thickness distribution is naturally conceivable on the electrode, and therefore there is an incomplete coating portion, which may cause liquid leakage and leakage. This is probably because the effect of suppressing the internal short circuit is imperfect. Therefore, under the same conditions, it is considered possible to improve the effect of suppressing liquid leakage and internal short circuit by making the coating film thickness to some extent, which makes the coating film thickness 1 μm. This can be confirmed from the fact that the effect of suppressing liquid leakage and internal short circuit is remarkably improved and a good suppressing effect is obtained.

When the coating film thickness is 1000 μm, good values are obtained in the liquid leakage rate and the internal short circuit rate, and a sufficient effect can be obtained in the effect of suppressing the liquid leakage and the internal short circuit. ing. On the other hand, the discharge time is slightly decreased and becomes an insufficient value. It is considered that the resistance of the coating film becomes so large that it cannot be ignored, and as a result, the discharge capacity decreases.

When the average molecular weight of the zinc-coated polymer compound is 500, the robustness of the film itself is insufficient even if the coating film thickness is increased to 500 μm, so that the electrolyte solution is impregnated or swelled. It is considered that this is caused by the diffusion of zincate ions as a result.

When the average molecular weight of the zinc-coated polymer compound is as large as 500,000, the uniformity of the polymer compound solution becomes insufficient, which causes a problem in the uniformity of the coating film thickness of the negative electrode. When the covering film thickness is sufficiently thick as 1000 μm, the effect is obtained by the effect of the thickness,
When the thickness is less than that, it is considered that the effect is insufficient because there is a region where the coating effect is small.

Taking the above into consideration, the average molecular weight of the zinc-coated polymer compound is preferably in the range of 1,000 to 100,000, more preferably in the range of 5,000 to 50,000, and the coating film thickness is 1 μm ~
It can be said that the range of 500 μm is preferable. When both of these two conditions are satisfied, it is considered possible to construct a high-quality alkaline zinc secondary battery that has an excellent effect of suppressing liquid leakage, internal short circuit, and discharge time.

Next, the effect of the alkyl chain length of the cationic functional group on the liquid leakage and internal short circuit of the alkaline zinc secondary battery will be described based on the results of Samples 38 to 53 below. Sample 38 to sample 4
In No. 7, a long-chain alkyl group having a carbon number of 2 or less is used as the cationic functional group, and in Samples 48 to 53, the long-chain alkyl group has 3 carbon atoms as the cationic functional group. The above cationic functional groups were used.

[Sample 38] An alkaline zinc secondary battery of Sample 38 was produced in the same manner as in Sample 1, except that triethylammonium chloride was introduced as a cationic functional group in the zinc-coated polymer compound.

[Sample 39] An alkaline zinc secondary battery of Sample 39 was produced in the same manner as in Sample 1 except that ethyldimethylammonium chloride was introduced as a cationic functional group in the zinc-coated polymer compound.

[Sample 40] An alkaline zinc secondary battery of Sample 40 was produced in the same manner as in Sample 1 except that diethylmethylammonium chloride was introduced as a cationic functional group in the zinc-coated polymer compound.

[Sample 41] An alkaline zinc secondary battery of Sample 41 was produced in the same manner as in Sample 1 except that trimethylphosphonium chloride was introduced as a cationic functional group in the zinc-coated polymer compound.

[Sample 42] An alkaline zinc secondary battery of Sample 42 was prepared in the same manner as in Sample 1 except that triethylphosphonium chloride was introduced as a cationic functional group in the zinc-coated polymer compound.

[Sample 43] An alkaline zinc secondary battery of Sample 43 was produced in the same manner as in Sample 1 except that ethyldimethylphosphonium chloride was introduced as a cationic functional group in the zinc-coated polymer compound.

[Sample 44] An alkaline zinc secondary battery of Sample 44 was produced in the same manner as in Sample 1 except that diethylmethylphosphonium chloride was introduced as a cationic functional group in the zinc-coated polymer compound.

[Sample 45] An alkaline zinc secondary battery of Sample 45 was prepared in the same manner as in Sample 1 except that dimethylsulfonium chloride was introduced as a cationic functional group in the zinc-coated polymer compound.

[Sample 46] An alkaline zinc secondary battery of Sample 46 was produced in the same manner as in Sample 1 except that diethylsulfonium chloride was introduced as a cationic functional group in the zinc-coated polymer compound.

[Sample 47] An alkaline zinc secondary battery of Sample 47 was prepared in the same manner as in Sample 1 except that ethylmethylsulfonium chloride was introduced as a cationic functional group in the zinc-coated polymer compound.

[Sample 48] An alkaline zinc secondary battery of Sample 48 was produced in the same manner as in Sample 1 except that dimethylpropylammonium chloride was introduced as a cationic functional group in the zinc-coated polymer compound.

[Sample 49] An alkaline zinc secondary battery of Sample 49 was produced in the same manner as in Sample 1 except that ethylmethylpropylammonium chloride was introduced as a cationic functional group in the zinc-coated polymer compound.

[Sample 50] An alkaline zinc secondary battery of Sample 50 was produced in the same manner as in Sample 1 except that diethylpropylammonium chloride was introduced as a cationic functional group in the zinc-coated polymer compound.

[Sample 51] An alkaline zinc secondary battery of Sample 51 was produced in the same manner as in Sample 1 except that dimethylhexyl ammonium chloride was introduced as a cationic functional group in the zinc-coated polymer compound.

[Sample 52] An alkaline zinc secondary battery of Sample 52 was produced in the same manner as in Sample 1 except that dimethylpropylphosphonium chloride was introduced as a cationic functional group in the zinc-coated polymer compound.

[Sample 53] An alkaline zinc secondary battery of Sample 53 was produced in the same manner as in Sample 1 except that methylpropylsulfonium chloride was introduced as a cationic functional group in the zinc-coated polymer compound.

Samples 38 to 38 produced as described above
With respect to the alkaline zinc secondary battery of Sample 53, liquid leakage resistance and internal short-circuit rate were evaluated in the same manner as in Samples 1 to 37. The results are shown in Table 2.

[0135]

[Table 2]

From Table 2, when the number of carbon atoms of the long-chain alkyl group of the cationic functional group is 2 or less, good results were obtained for both the liquid leakage rate and the internal short circuit rate, and It can be seen that the effect of suppressing liquid leakage and internal short circuit is sufficiently obtained. On the other hand, when the number of carbon atoms of the long-chain alkyl group of the cationic functional group is 3 or more, both the liquid leakage rate and the internal short circuit rate are large, and the liquid leakage of the alkaline zinc secondary battery
It can be seen that the effect of suppressing the internal short circuit is reduced. This is due to the effect of physical steric hindrance caused by the alkyl chain having 3 or more carbon atoms occupying a large volume spatially,
It is considered that this is due to the positive charge blocking effect of the alkyl chain. Therefore, from these facts, by using a cationic functional group having a carbon number of the long-chain alkyl group of 2 or less, good liquid leakage and internal short-circuit suppressing effect can be obtained, and liquid leakage resistance and cycle life are excellent. It can be said that an alkaline zinc secondary battery is feasible.

[0137]

The alkaline zinc battery according to the present invention comprises a negative electrode containing zinc or a zinc alloy as a negative electrode active material,
An alkaline zinc battery comprising a positive electrode, a separator, and an alkaline electrolyte, in which a cationic organic substance is disposed near the surface of the negative electrode.

In the alkaline zinc battery according to the present invention configured as described above, since the cationic organic substance is arranged in the vicinity of the surface of the negative electrode, the deposition and growth of dendritic or spongy zinc on the negative electrode can be suppressed. In addition, the generation of hydrogen gas can be suppressed.

As a result, it is possible to prevent the occurrence of an internal short circuit due to the growth of dendritic or spongy zinc on the surface of the negative electrode, to improve the cycle life, and to prevent leakage due to the generation of hydrogen gas. It is possible to prevent liquid.

Therefore, according to the present invention, it is possible to provide an alkaline zinc battery excellent in leakage resistance and cycle life, that is, an alkaline zinc battery excellent in storage property and charge / discharge performance.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing one structural example of an alkaline zinc secondary battery to which the present invention is applied.

[Explanation of symbols] 1 positive electrode can 2 Negative electrode lid 3 insulating packing 4 separator 5 Positive electrode 6 Positive electrode current collector 7 Negative electrode 8 Negative electrode current collector 9 Positive lead wire 10 Negative lead wire

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kano Iwataro             6-735 Kita-Shinagawa, Shinagawa-ku, Tokyo Soni             -Inside the corporation (72) Inventor Goro Shibamoto             6-735 Kita-Shinagawa, Shinagawa-ku, Tokyo Soni             -Inside the corporation F-term (reference) 5H050 AA18 AA20 BA11 CA02 CA03                       CA05 CA12 CB13 DA03 DA09                       EA03 EA04 EA09 EA12 EA22                       EA23 EA24 FA05 FA17 HA04                       HA11 HA12

Claims (9)

[Claims] 1. An alkaline zinc battery comprising a negative electrode containing zinc or a zinc alloy as a negative electrode active material, a positive electrode, a separator, and an alkaline electrolyte, wherein a cationic organic compound is provided near the surface of the negative electrode. The alkaline zinc battery characterized in that 2. The cationic organic compound is one or more of a quaternary ammonium salt, a quaternary phosphonium salt, and a tertiary sulfonium salt.
The alkaline zinc battery described. 3. The alkaline zinc battery according to claim 1, wherein the negative electrode is covered with a film of a polymer compound in which the cationic organic substance is introduced into a side chain as a cationic functional group. 4. The alkaline zinc battery according to claim 3, wherein the polymer compound is a polymer of styrene. 5. The polymer compound as claimed in claim 3, which is a copolymer of styrene and divinylbenzene.
The alkaline zinc battery described. 6. The average molecular weight of the polymer compound is 10
The alkaline zinc battery according to claim 3, wherein the alkaline zinc battery is from 00 to 100,000. 7. The average molecular weight of the polymer compound is 50.
It is 00-50000, The alkaline zinc battery of Claim 3 characterized by the above-mentioned. 8. The polymer compound film having a thickness of 1 μm
The alkaline zinc battery according to claim 3, wherein the alkaline zinc battery has a thickness of ˜500 μm. 9. The cationic functional group introduced into the polymer compound is trimethylammonium group, dimethylethylammonium group, methyldiethylammonium group, triethylammonium group, trimethylphosphonium group, dimethylethylphosphonium group, methyldiethylphosphonium. The alkaline zinc battery according to claim 3, wherein the alkaline zinc battery is one or more of a group, a triethylphosphonium group, a dimethylsulfonium group, a methylethylsulfonium group, and a diethylsulfonium group.