JPH1126013A - Sealed metal oxide-zinc storage battery and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a storage battery with improved negative electrode reaction characteristic, suppressed dendrite, and superior in preservation characteristic by forming the electrode base of a negative electrode with a three-dimensional mesh metal porous body made of one from among silver, copper, tin, brass and bronze, forming the inner face of a battery case with the same material as the electrode base, and arranging the negative electrode in direct contact with the battery case. SOLUTION: An electrode base constituting a zinc electrode is manufactured as follows. A paste mixed with conductive carbon powder and water is filled into a foam urethane resin so as to impart conductivity to the surface of the resin. A metal plated layer is formed on the surface with a plating liquid of silver, copper, tin or the like. It is heated in air to burn foam urethane and carbon, and a metal porous body is formed. Since a part of the metal is oxidized in this process, a strong metal porous body is obtained after being sintered in the reducing atmosphere.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a negative electrode such as a nickel oxide-zinc storage battery and a silver oxide-zinc storage battery and a battery case for housing the negative electrode.

[0002]

2. Description of the Related Art Zinc used as a negative electrode active material for alkaline storage batteries has been researched and developed because of its high energy density per unit weight, low cost, and non-polluting characteristics. It has not yet been widely used. This is because zinc is a soluble electrode. That is, at the time of discharging, zinc dissolves in the alkaline electrolyte as zincate ions, and at the time of the next charge, the zincate ions are deposited on the zinc surface. Electrodeposited as metallic zinc. The repetition of charge / discharge causes deformation of the shape of the electrodeposited zinc, resulting in non-uniform charge / discharge reaction, leading to a reduction in zinc discharge capacity. Further, the growth of acicular zinc called resinous zinc crystal (dendrites) occurs, penetrates through the separator and makes electrical contact with the positive electrode, causing an internal short circuit and making charging and discharging impossible. Various proposals have been made to solve these problems, but no method that can fundamentally solve them has been found at present. It is said that it is effective to include metallic zinc as a dischargeable substance in the negative electrode active material in order to suppress a decrease in the discharge capacity of the zinc electrode due to the non-uniform charge / discharge reaction described above. ing. This is because the metallic zinc added to the active material can contribute to the discharge together with the metallic zinc obtained by charging from the zinc oxide.

However, since zinc, which is a starting material, is difficult to obtain a powder having a small particle size as compared with zinc oxide, it tends to become a nucleus for the growth of resinous crystals during charging, and is subject to rapid charging or charging at a high temperature. It is disclosed that an internal short circuit is likely to occur when performing the method (Japanese Patent Laid-Open No. 2-30062). Therefore, if only a fine zinc powder can be used as a starting material, an internal short circuit can be suppressed.

[0004] However, ordinary zinc oxide powder has poor conductivity and causes a decrease in the charging efficiency particularly at the time of initial charging, generating hydrogen gas and increasing the internal pressure in a sealed battery. Further, there is a disadvantage that the discharge of a large current greatly reduces the discharge capacity and discharge voltage.

On the other hand, metal zinc formed by charging contacts a dissimilar metal in the presence of an alkaline electrolyte to form a local battery, which undergoes oxidation to generate hydrogen gas.

[0006]

Problems to be Solved by the Invention Existing nickel-cadmium storage batteries (hereinafter abbreviated as Ni / Cd storage batteries), nickel-cadmium storage batteries,
Like a hydrogen storage battery (hereinafter abbreviated as Ni / MH storage battery), it is necessary to adopt a sealed battery structure in order to be easy to maintain and enable a wide range of applications. For this purpose, it is necessary to minimize the generation of gas during charging or storage to suppress an increase in battery internal pressure.

There is a strong demand for smaller and lighter portable electronic devices, and Ni / Cd storage batteries and Ni / MH batteries are now widely used.
Similarly, storage batteries are required to be smaller and lighter. Therefore, high energy density of a battery having a large amount of energy per unit weight or unit volume has been actively studied. It is expected that a secondary battery using a zinc electrode can be sealed and have a high energy density for the same reason.

From such a viewpoint, it is considered that a battery structure similar to the above-described Ni / Cd storage battery or Ni / MH storage battery is an effective means for increasing the capacity of the battery. When a nickel-zinc storage battery is constructed similarly to these batteries, the zinc electrode comes into contact with the metal case. Normally, this type of battery case requires a structure that can withstand a pressure rise, a material that is resistant to corrosion even with an alkaline electrolyte, and a material that can be reduced in cost. Bottomed metal containers are widely used. Therefore, the zinc electrode comes into contact with the metal case plated with nickel with an alkaline electrolyte interposed.

In such a configuration, self-discharge occurs due to dissolution of zinc, and hydrogen gas is generated, which leads to a decrease in discharge capacity and an adverse effect of an increase in internal pressure. The dissolution of zinc is because the electrochemical electrode potential shows a lower potential than nickel, which forms a kind of local battery, and zinc is oxidized and nickel is reduced.

Therefore, it is necessary to use a metal case in which such a phenomenon hardly occurs even when it comes into contact with zinc. On the other hand, the zinc electrode changes into zinc oxide and zinc hydroxide by discharging, but zinc oxide, which is a discharge product, dissolves in an aqueous solution of potassium hydroxide, which is the main component of the electrolytic solution, and precipitates as zinc metal when charged I do. In this process,
Since the metal zinc is not always deposited at the location of the base metal zinc, a shape change occurs.

Therefore, it is an effective method to extend the cycle life of the battery to devise such a phenomenon so as not to occur, but it is a major technical problem at present.

An object of the present invention is to solve the above-mentioned problems, and an object of the present invention is to provide a sealed metal oxide-zinc battery having improved negative electrode reaction characteristics, suppressed dendrite, and excellent storage characteristics.

[0013]

In order to constitute a metal oxide-zinc storage battery having a high energy density and a long cycle life, the present invention employs the following construction.

As the electrode support material constituting the zinc electrode,
Silver, on which a local battery is difficult to form even when in contact with metallic zinc,
By using copper, tin or an alloy thereof, the inner surface of the battery case was also made of the same material as the electrode support to prevent self-discharge of zinc, and a battery case having excellent pressure resistance and low cost was adopted.

On the other hand, with respect to the change in the shape of the zinc electrode due to charge and discharge, in addition to the prior art method of dissolving the discharge product in the electrolytic solution and the method of setting the amount of the electrolytic solution to the minimum necessary, The use of a three-dimensional reticulated metal porous body for the electrode support to improve conductivity and enable the application of fine zinc oxide powder that does not easily change in shape, and is preferably used for the electrode support. The powder of the same material was mixed in a zinc electrode.

[0016]

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a positive electrode having an active material mainly composed of a metal oxide, a negative electrode having an active material mainly composed of zinc oxide, a separator interposed between the positive and negative electrodes, an alkaline electrolyte and a bottomed material. In a metal oxide-zinc storage battery using a metal container as a battery case, the electrode support of the negative electrode is a three-dimensional mesh-like metal porous body made of a metal or an alloy selected from silver, copper, tin, brass, and bronze. The inner surface of the battery case is made of the same material as the electrode support,
Further, the sealed metal oxide-zinc storage battery is characterized in that the negative electrode is disposed so as to be in direct contact with the battery case.

The electrode support constituting the zinc electrode was manufactured by the following steps. Conductive carbon powder and water are mixed together, made into a paste, and filled into a foamed urethane resin to impart conductivity to the foamed urethane resin surface. Then, a plating layer of the metal is formed on the surface using a plating solution of silver, copper, tin, or the like, and the plated silver and copper are heated in the air to burn foamed urethane and carbon, thereby burning the metal. Is formed. Since a part of the metal is oxidized by this process, a strong metal porous body is formed by sintering in a reducing atmosphere.

In the case of tin plating, since the melting point of tin is low, it is prepared by heating in a reducing or inert atmosphere and then dissolving polyurethane with an organic solvent.

When an alloy that cannot be plated is used for the electrode support, the powder of the alloy is directly charged into a foamed urethane resin, and roasted in air and sintered in a reducing atmosphere. Thus, a porous body of the alloy was formed. In this method, not only the alloy but also a metal powder (copper, silver, or the like) can be used as a starting material.

The metal or alloy three-dimensional mesh-like metal porous body obtained by the above-mentioned method is filled in a paste form with an aqueous solution of zinc white (zinc oxide powder) and a binder. Make a zinc electrode.

On the other hand, the battery case housing the power generating element
A steel plate or a nickel-plated steel plate is formed into a bottomed cylindrical container by drawing. If the steel plate is not nickel-plated, nickel plating is applied after the processing to prevent corrosion. A plating layer of the same metal material (silver, copper, tin) used for the zinc electrode support is formed on the inner surface of such a bottomed cylindrical container. The alloy material that cannot be plated was prepared by a method of processing a material obtained by cladding a nickel-plated steel plate and an alloy plate into a bottomed cylindrical container.

[0022]

Embodiments of the present invention will be described below with reference to the drawings.

In addition to the zinc electrode and the bottomed cylindrical container, a nickel metal electrode, a separator, and an electrolytic solution are used as a known metal oxide positive electrode to form a cylindrical sealed battery shown in FIG. Investigated in detail.

A nickel-plated steel plate also serving as a negative electrode terminal is mechanically drawn and drawn to form a bottomed metal container, necessary degreasing is performed, and then the apparatus shown in FIG.
A plating solution was circulated in the bottomed metal container, copper plating was performed only on the inner surface, and a case a was performed until the plating thickness became 6 to 9 μm. Similarly, case b and case c plated with silver and tin were prepared.

On the other hand, in order to form an alloy layer in a bottomed metal container, a bottom plate is formed by drawing using a metal plate obtained by integrating a nickel-plated steel plate and a brass plate or a nickel-plated steel plate and a bronze plate by cladding. Metal container cases d and e were produced. As a comparative example, an AA size bottomed metal container case f used for Ni / Cd storage batteries and Ni / MH storage batteries was used (a nickel-plated steel plate was drawn and formed into a bottomed cylindrical metal container).

A method for producing a zinc electrode electrode support and a method for producing a zinc electrode using the same will be described in detail. The three-dimensional network porous body of copper, silver, and tin was produced as follows.

The foamed polyurethane processed into a sheet is immersed in a paste made into a mud with an aqueous solution of graphite powder and carboxymethyl cellulose, and the graphite powder is filled into pores of the foam through a vacuum impregnation step. Then dry. As a result, a mixed layer of graphite and carboxymethyl cellulose is formed on the surface of the foamed urethane, and the polyurethane, which is an insulating material, becomes conductive.

Next, using a copper, silver, and tin electroplating solution, the surface of the graphite-coated polyurethane was plated with each metal. 68~74mg / cm ² in the case where the weight of the polyurethane after plating at this time of copper, 83~89mg in the case of silver
/ cm ^2, it was adjusted plating amount such that the 48~54mg / cm ² in the case of tin. The copper and silver foams after plating are heated in the air, and the polyurethane, graphite, binders, etc. are removed by roasting, and reduced in a reducing atmosphere for the purpose of reducing partially oxidized metal parts and firmly bonding the metal layers. To produce copper and silver three-dimensional mesh metal porous bodies Cu-1 and Ag-1.

Since tin has a low melting point and cannot be produced by the above-described method, it is heated in a reducing or inert atmosphere to melt a part of tin and form a strong layer. The polyurethane was dissolved and separated by the method described above to produce a three-dimensional reticulated metal porous body Sn-2.

When the three-dimensional mesh-like porous metal body is composed of a single element, it can be produced by plating, but in the case of an alloy, it is difficult to obtain an alloy layer having a uniform composition. Was prepared by the method shown in FIG.

Brass (90% copper, 10% zinc), bronze (90% copper,
An alloy powder of tin (10%) is mixed with an aqueous solution of carboxymethyl cellulose to form a paste having fluidity, vacuum impregnated into the foamed polyurethane resin processed into the sheet shape described above, and the alloy powder is filled into the porous body. I do. The filling amount was set so that the polyurethane weight after drying was 68 to 74 mg / cm ² . In the subsequent steps, Cu-Zn-1 and Cu-Sn-1 were prepared by performing roasting and sintering in the same manner as the copper and silver three-dimensional foamed metal porous bodies obtained by the plating method.

The types and physical properties of the three-dimensional network porous metal body produced as described above are summarized in Table 1, and as a comparative example, the three-dimensional network porous body Ni-1 using nickel and a copper plate were machined. The prepared punched metal having a hole diameter of 1.7 mm and an aperture ratio of 42% is also shown in the same table.

[0033]

[Table 1] A method for producing a zinc electrode using these porous bodies will be described below.

The three-dimensional reticulated metal porous body shown in Table 1 was
It was cut into a size of 80 mm and processed in advance to a thickness of 0.8 mm by a roller press. A paste made of an aqueous solution of zinc oxide powder (average particle diameter: 0.4 μm) and carboxymethyl cellulose was filled into the porous body using these porous bodies, and after being dried, pressed to 0.5 mm.

In addition to the zinc oxide, 10 wt% and 20 wt% of zinc oxide as well as the conventional metal zinc powder (average particle diameter 5 μm, purity 99.9 or more prepared by the distillation method) are added to the zinc oxide. The prepared electrode was also prepared. Further, in order to improve the conductivity of a powder of the same material as the three-dimensional mesh-like porous metal body of the present invention, an electrode was also prepared by adding 10 wt% to zinc oxide powder, and as one of comparative examples, copper punching was performed. An electrode was fabricated by disposing a metal in the center and applying a paste of zinc oxide powder in an aqueous solution of carboxymethyl cellulose.

These electrodes were cut into a size of 39 × 80 mm to form an AA battery, and the specifications of the obtained electrodes AP are shown in Table 2. The packing density in the table is based on the theoretical electrochemical capacity (zinc: 820 mAh / g, zinc oxide:
659 mAh / g).

[0037]

[Table 2] Using these zinc electrodes, prototypes of AA batteries, which are cylindrical sealed batteries, are manufactured, battery characteristics are evaluated, and the effects of the present invention will be described. As the positive electrode, an electrode obtained by adding a nickel hydroxide powder, a metal cobalt powder, and a cobalt compound powder to a foamed nickel porous body, which is a known non-sintered nickel electrode, is used.
Electrodes with electrochemical theoretical capacity of 5-895 mAh were used.

As the separator, a nonwoven fabric made of polyamide and a film obtained by graft copolymerizing a hydrophilic monomer with polyethylene were used in combination. Two separators are arranged between a nickel electrode and a zinc electrode and spirally wound, and the same material as the electrode support used for the zinc electrode is combined with a battery case formed on the inner surface of a bottomed metal container case. A battery as shown in FIG. As the electrolytic solution, 10 g / l of lithium hydroxide monohydrate (LiOH.H ₂ O) and a saturated solution of zinc oxide powder in a 7N aqueous potassium hydroxide solution were used, and 2.0 ml of the solution was injected per cell. .

Batteries using the zinc electrodes A to P thus prepared were designated as A-1 to P-1, respectively, and zinc electrodes A to D were used as a part of a comparative example, and the batteries were put into practical use. A-2 to D-2 using battery cases used for Ni / Cd storage batteries and Ni / MH storage batteries (battery cases in which nickel-plated steel sheets are machined and nickel-plated layers are formed on the inner surface)
Were similarly configured. 20 ° C using these batteries
The charging current was set to 0.1 C (80 mA) in the atmosphere described above, the operation was performed for 12 hours, a 1-hour pause was provided, and then the battery was discharged at a current of 0.2 C (160 mA) until the battery voltage reached 1.2 V. This process was repeated five times as one cycle.

Table 3 shows the relationship between the obtained battery type and the discharge capacity. Also, the discharge current at the sixth cycle is
The same table shows the results obtained by measuring the discharge capacity by increasing the discharge current at the seventh cycle to 3 C (2400 mA) at 1 C (800 mA) and the ratio to the discharge capacity at the fifth cycle.

[0041]

[Table 3] From these test results, copper as the electrode support for the zinc electrode,
Batteries A-2 to D-2 in which nickel was formed on the inner surface of the electrode support similar to batteries A-1 to D-1 in which copper was formed on the inner surface of the battery case
, A large difference is observed in the discharge capacity in the first to fifth cycles. It is considered that the cause of this was that the electrolyte was released from the safety valve shown in FIG. 1 during charging and discharging, and the contact between nickel and zinc dissolved zinc, resulting in the generation of hydrogen gas and an increase in battery internal pressure. It is considered that the electrolyte solution became insufficient due to this phenomenon, and the decrease in the discharge capacity increased due to repeated charge and discharge.

Therefore, a nickel layer is formed on the inner surface of the battery case, and in a battery system in which a zinc electrode is provided on the outermost periphery of the group, gas generation is large and it is difficult to obtain a discharge capacity. It is an important factor for a nickel-zinc storage battery, especially a sealed battery, to select a battery construction method in which hydrogen generation is unlikely to occur even in the presence of a liquid or in contact with metallic zinc like copper. In addition, the same phenomenon was observed in the battery of M-1 as a comparative example, and the discharge capacity was greatly reduced due to repetition of charge / discharge. What happened is considered to be a major cause. The batteries of E-1 to L-1 of the present invention did not show a significant change in the discharge capacity up to the first to fifth cycles, so that the above-mentioned adverse effects of gas generation were not observed, and good results were obtained. . This proved that the present invention in which the battery case inner surface material and the electrode support were made of the same material was effective.

Further, E-1 and F-1, G-1 and H-1, I-1 and J-1,
In the comparison between K-1 and L-1, adding a powder of the same material as the electrode support to the zinc electrode does not show a large difference in the charge capacity from the first to the fifth cycle, but the sixth cycle, The result that the discharge capacity at the seventh cycle was increased was obtained. This is due to the fact that the electron conductivity in the electrode was improved by adding powder, the discharge voltage was increased, and the active material (metal zinc)
It is considered that the active material utilization rate is improved due to an increase in the proportion of the conductive material around the metal, and it can be said that the addition of a metal or alloy powder capable of improving the high rate discharge characteristics is an effective means.

As a comparative example, an N-1 battery comprising electrodes using a copper punching metal, which is a flat metal porous body, as an electrode support for a zinc electrode. Although there was no significant difference as compared with A-1 of the invention, the discharge capacity tended to decrease significantly due to the large current discharge. In the O-1 and P-1 batteries to which copper powder was added using the same punching metal, the characteristics were slightly improved, but the discharge capacity was smaller than that of the three-dimensional mesh metal porous body. It is considered that these causes are due to the decrease in the electron conductivity described above, and in particular, the conductivity in the thickness direction of the electrode is deteriorated due to the porous body on the plane.

Next, these batteries were charged at a current of 0.2 C (160 mA) for 6 hours, and after a pause of 1 hour, charge / discharge was repeated under the conditions of discharging at a current of 0.5 C (400 mA) to a discharge voltage of 1.2 V. Table 4 shows the cycle life characteristics obtained by measuring the change in the discharge capacity at the time. In addition, the result of the initial characteristics was not preferable A-2
The life characteristics of D-2 and M-1 were not evaluated.

[0046]

[Table 4] From the results in Table 4, the effect of the electrode obtained by adding metallic zinc to the zinc electrode is understood. In the comparison between the present invention A-1 and the comparative examples B-1 and C-1, the cycle life of the battery of A-1 is longer. , B-1, C-1
No discharge capacity was obtained. In the batteries of B-1 and C-1, the zinc electrode was deformed by charge and discharge and the growth of tendrites occurred, penetrating the separator, and a short circuit phenomenon was observed, so that the discharge became impossible. The main cause of the short-circuit phenomenon is the addition of zinc metal.Metal zinc having a large particle diameter tends to become a nucleus for forming dendrites, and tetrahydrozinc zincate ion (Zn (OH) ₄ ^2- ) dissolved by discharge causes metal It is considered that they were selectively deposited on the surface of the zinc particles.

As described above, zinc metal is conductive and acts as an active material for a zinc electrode. However, it is difficult to obtain fine particles as compared with zinc oxide in the production method. Has a negative effect.

Also, batteries A-1, E-1, G-1, I-1, and B-1 each comprising an electrode using zinc oxide as a raw material of the zinc electrode of the present invention and a three-dimensional mesh porous metal as an electrode support. In the cycle life test of K-1, the discharge capacity was maintained at 70% or more compared to the initial discharge capacity even after 250 charge / discharge cycles. Therefore, it is considered that the battery active life was extended because the electrode active material was held by the three-dimensional electrode support, the charge / discharge reaction proceeded uniformly in the electrode, and no deformation or dendrite occurred.

Furthermore, batteries D-1, F-1, H-1, J-1, and B-1 to which a powder of the same material as the three-dimensional porous metal body of the present invention was added.
L-1 has no adverse effect on the battery life and can improve the high-rate discharge characteristics described above, indicating that it is a high-performance battery construction means. In the examples, the amount added is
Although shown as being limited to 10 wt%, the effect is recognized even if it is less than that, and conversely, if it is more, it can be predicted that it is effective for high rate discharge characteristics, but the filling of zinc oxide which is an electrode active material Since the amount is reduced, a high-capacity battery cannot be designed, and the upper limit is naturally limited.

On the other hand, batteries N-1 and O- made of electrodes prepared by using a copper punching metal which is a part of a planar porous metal body as an electrode support for a zinc electrode as a comparative example.
1. As is clear from the results of the cycle life characteristic test of P-1, the decrease in the discharge capacity as well as the charging and discharging of the electrode to which the copper powder was added was larger than that of the batteries of A-1 and D-1.
It is considered that this difference is due to the planar or three-dimensional shape of the electrode support, and the former has a lower current collecting property than the latter and tends to cause non-uniform charge / discharge reactions. Further, it is considered that the electrode active material layer also showed a peeling phenomenon from the electrode support, the current collecting effect was deteriorated, and the discharge capacity was reduced.

In the embodiment, the nickel positive electrode mainly composed of nickel hydroxide as the metal oxide has been described. However, a similar effect is recognized even with a positive electrode using silver oxide which is one of the same metal oxides. It can be said that the invention is effective. In addition, in the embodiment, a method of forming a tin layer on a foamed polyurethane by electroplating and dissolving and removing the foamed polyurethane with an organic solvent for a low melting point metal material such as tin has been described. The same effect is also observed in a three-dimensional mesh metal porous body that is immersed in molten tin using the original mesh porous body and formed tin only on the surface layer (generally called solder plating). Was done.

[0052]

As described above, according to the present invention, as a negative electrode, an electrode obtained by filling a fine three-dimensional reticulated metal porous body with fine zinc oxide powder is used as an electrode support for a zinc electrode. Combined with a positive electrode having a main body, a battery case in which a metal layer of the same material as the three-dimensional mesh-like metal porous body is formed on the inner surface of the bottomed metal container, and a negative electrode on the outermost periphery of a spirally wound power generating element. Is exposed and a battery structure is brought into direct contact with the battery case, whereby it is possible to improve the electrode reaction of the zinc oxide powder having poor conductivity, and it is possible to suppress the adverse effects of dendrites.

In addition, the present invention can reduce the generation of hydrogen gas due to the formation of a local battery, improve storage characteristics, and effectively use the volume in the battery case, thereby enabling the construction of a high capacity battery. Has a very high industrial value.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an AA nickel-zinc storage battery used in an embodiment.

FIG. 2 is a diagram showing an apparatus for plating the inner surface of a bottomed metal container.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 nickel positive electrode 2 zinc negative electrode 3 separator 4 battery case also serving as negative electrode terminal 5 sealing plate 6 metal layer formed on inner surface of battery case 7 gasket (insulation of positive and negative electrodes and ensuring sealing property) 8 positive electrode terminal 9 positive electrode collection Electric body 10 Rubber valve body of safety valve 11 Metal container with bottom 12 Plating counter electrode (material forming plating layer) 13 Cathode terminal of plating power supply 14 Anode terminal of plating power supply 15 Pump for circulation of plating solution 16 Plating solution storage container

Claims (6)

[Claims] A positive electrode having an active material mainly composed of a metal oxide; a negative electrode having an active material mainly composed of zinc oxide;
In a metal oxide-zinc storage battery using a battery case that is a separator, an alkaline electrolyte and a bottomed metal container interposed between negative electrodes, the electrode support of the negative electrode is silver, copper, tin,
A three-dimensional mesh metal porous body made of a kind of metal or alloy selected from brass and bronze, wherein the inner surface of the battery case is made of the same material as the electrode support, and the negative electrode is in direct contact with the battery case. A sealed metal oxide-zinc storage battery, characterized in that the battery is arranged as described above. 2. The sealed metal oxide-zinc storage battery according to claim 1, wherein the metal oxide is a nickel oxide. 3. The sealed metal oxide according to claim 1, wherein a powder of the same material as the electrode support is contained in the negative electrode active material.
Zinc battery. 4. The sealed metal oxide according to claim 1,
The silver or copper three-dimensional reticulated metal porous body used for the zinc storage battery is a process of imparting conductivity to the surface of the foamed polyurethane resin, a process of forming a metal layer of silver or copper by electroplating, A method for producing a sealed metal oxide-zinc storage battery, characterized by being produced by a process of roasting a polyurethane resin and thereafter sintering silver and copper in a reducing atmosphere. 5. The sealed metal oxide according to claim 1,
A three-dimensional mesh metal porous body made of any of silver, copper, brass and bronze used for zinc storage batteries is filled with one type of powder selected from silver, copper, brass and bronze inside the foamed polyurethane resin A method for producing a sealed metal oxide-zinc storage battery, characterized in that it is produced by a step of performing, a step of roasting a foamed polyurethane resin, and a step of sintering silver, copper, brass, and bronze in a reducing atmosphere. 6. The three-dimensional mesh metal porous body used for a sealed metal oxide-zinc storage battery according to claim 1, which is made of tin, wherein a step of imparting conductivity to the surface of the foamed polyurethane resin is performed by electroplating. A method for producing a sealed metal oxide-zinc storage battery, comprising: a step of forming a layer of tin; a step of heat-treating in a reducing or inert atmosphere; and a step of removing a foamed polyurethane resin with an organic solvent. .