JP7176942B2 - alkaline battery - Google Patents

Description

The present disclosure relates to alkaline batteries. In particular, the present disclosure relates to alkaline batteries having negative electrodes containing zinc composite hydroxide as the negative electrode active material.

Zinc is abundantly present on the earth, and while it is an inexpensive material, it has a high theoretical capacity density as an active material for batteries. For this reason, zinc batteries having zinc and/or zinc-containing compounds (for example, zinc oxide, etc.) as negative electrode active materials have long attracted attention.

As such zinc batteries, for example, nickel/zinc batteries, air/zinc batteries, manganese/zinc batteries or zinc ion batteries, silver/zinc batteries, etc. have been studied.

However, zinc (Zn) generates a zincate anion (Zn(OH) ₄ ^2- ) soluble in a strong alkaline electrolyte as a discharge product by the discharge reaction shown in the following reaction formula (1):
Discharge reaction: Zn+4OH ^- → Zn(OH) ₄ ^2- +2e ^- ... reaction formula (1)

In order to suppress such dissolution of the zinc component in the electrolyte, a battery using a zinc negative electrode normally uses a strong alkaline aqueous solution in which zinc oxide (ZnO) is dissolved as the electrolyte.

However, even if the zinc oxide is saturated, the zincate anion is supersaturated and dissolved to a concentration several times higher than the saturated solubility. Therefore, the zincate anion generated by the discharge easily diffuses and moves in the electrolyte. be able to.

In the process of charging or discharging the negative electrode, if the concentration of the zincate anion locally exceeds the supersaturated solubility, or if the concentration of hydroxide ions (OH ⁻ ) in the electrolyte becomes locally low, supersaturation of the zincate anion occurs. When the solubility is reduced, the zincate anion precipitates as solid zinc oxide by the reaction shown in the following reaction formula (2):
Zn(OH) ₄ ²⁻ →ZnO+H ₂ O+2OH ⁻ Reaction formula (2)

That is, it is considered that the zinc oxide is repeatedly deposited and deposited at similar locations in the negative electrode due to repeated charging and discharging, and thus the shape change of the zinc negative electrode progresses.

In order to solve such problems, Patent Literatures 1 and 2 respectively disclose a technique of using a zinc-based negative electrode coated and a layered double hydroxide (LDH) instead of zinc and/or zinc oxide for the negative electrode. A technique used as

More specifically, in Patent Document 1, one or more metal oxides selected from titanium (Ti), zirconium (Zr), magnesium (Mg), tin (Sn), and yttrium (Y) are included, and a specific A zinc negative electrode material for a secondary battery has been proposed in which a zinc-containing active material is coated with a coating composition having a surface uneven distribution ratio of .

Further, in Patent Document 2, as a positive electrode active material, a positive electrode containing a layered double hydroxide (LDH) containing at least one selected from the group consisting of Ni, Fe, and Mn as a constituent element, and as a negative electrode active material A negative electrode containing a layered double hydroxide (LDH) containing at least one selected from the group consisting of Cu, Al and Zn as a constituent element, an alkaline electrolyte and / or a hydroxide ion conductive solid electrolyte , a secondary battery has been proposed.

WO2017/077991 JP 2018-133324 A

However, Patent Documents 1 and 2 still have room for development and improvement in terms of discharge capacity.

Accordingly, the present disclosure has been made in view of the circumstances described above, and an object of the present disclosure is to provide an alkaline battery capable of improving discharge capacity.

The inventors of the present disclosure have found that the above problems can be solved by the following means.

<Aspect 1>
An alkaline battery having a negative electrode, a positive electrode, and an alkaline electrolyte,
The negative electrode contains, as a negative electrode active material, a zinc composite hydroxide having the following (a) to (c): (a) zinc hydroxide, (b) aluminum dissolved in the zinc hydroxide and (c) anions other than hydroxide ions, and with respect to the total metal elements in the zinc composite hydroxide, the zinc element is 70.0 mol% or more, and the aluminum element is 30.0 mol. % or less,
alkaline battery.
<Aspect 2>
The alkaline battery according to aspect 1, wherein the anion is at least one selected from the group consisting of a carbonate anion, a sulfate anion, and a phosphate anion.
<Aspect 3>
The alkaline battery according to aspect 1 or 2, wherein the alkaline electrolyte contains an anion of the same kind as the anion.
<Aspect 4>
The alkaline battery according to aspect 3, wherein in the alkaline electrolyte, the same kind of anion is 0.1 mol or more per 1 mol of hydroxide ion of the alkali salt.
<Aspect 5>
The zinc composite hydroxide further has (d) a metal other than aluminum dissolved in the zinc hydroxide,
The valence of the metal other than aluminum is 3 or more, and the metal element other than aluminum is less than 20.0 mol% with respect to the total metal elements in the zinc composite hydroxide.
The alkaline battery according to any one of aspects 1-4.
<Aspect 6>
The alkaline battery according to aspect 5, wherein the metal other than aluminum is at least one selected from the group consisting of yttrium, titanium, zirconium, and molybdenum.
<Aspect 7>
The alkaline battery according to any one of aspects 1 to 6, wherein the zinc composite hydroxide further contains water of crystallization.
<Aspect 8>
The alkaline battery according to any one of aspects 1 to 7, wherein the positive electrode contains nickel hydroxide as a positive electrode active material.
<Aspect 9>
9. The alkaline battery of any one of aspects 1-8, wherein the alkaline electrolyte is not saturated with zinc or zinc oxide.
<Aspect 10>
The alkaline battery according to any one of aspects 1 to 9, which is a secondary battery.

According to the alkaline battery of the present disclosure, the discharge capacity can be improved.

1 is a diagram plotting the results of charge-discharge tests of alkaline batteries of Example 1, Comparative Examples 1 and 2. FIG. FIG. 2 is a diagram plotting the results of charge-discharge tests of alkaline batteries of Examples 1 to 3. FIG. FIG. 10 is a diagram plotting the results of charge-discharge tests of alkaline batteries of Examples 4 to 6; FIG. 10 is a diagram plotting the results of charge-discharge tests of alkaline batteries of Examples 7 and 8; FIG. 10 is a diagram plotting the results of charge-discharge tests of alkaline batteries of Examples 9 and 10; FIG. 10 is a diagram plotting the results of charge-discharge tests of alkaline batteries of Examples 11 and 12;

Hereinafter, embodiments of the present disclosure will be described in detail. It should be noted that the present disclosure is not limited to the following embodiments, and various modifications can be made within the scope of the gist of the present disclosure.

《Alkaline battery》
The alkaline battery of the present disclosure is
An alkaline battery having a negative electrode, a positive electrode, and an alkaline electrolyte,
The negative electrode contains a zinc composite hydroxide having the following (a) to (c) as a negative electrode active material: (a) zinc hydroxide, (b) aluminum dissolved in zinc hydroxide, and (c) anions other than hydroxide ions, and zinc element is 70 mol % or more and aluminum element is 30 mol % or less with respect to the total metal elements in the zinc composite hydroxide.

<Negative electrode>
In the present disclosure, a negative electrode includes a negative electrode material and a negative current collector.

The form of the negative electrode is not particularly limited, and for example, a negative electrode material is formed in layers on a plate-like negative electrode current collector, or a foam-like negative electrode current collector, particularly an open-cell structure-like negative electrode current collector. can be exemplified by coating or filling with a negative electrode material.

(Negative electrode active material)
In the present disclosure, the negative electrode active material is zinc composite hydroxide having the following (a) to (c):
(a) zinc hydroxide,
(b) aluminum dissolved in zinc hydroxide, and (c) anions other than hydroxide ions,
And the zinc element is 70 mol % or more and the aluminum element is 30 mol % or less with respect to the total metal elements in the zinc composite hydroxide.

According to the intensive research of the present inventors of the present disclosure, by using the zinc composite hydroxide having the zinc element and the aluminum element in the specific mol% range as described above as the negative electrode active material, alkaline batteries It was found that the discharge capacity of was able to be improved.

In the present disclosure, "zinc composite hydroxide" means a hydroxide in which at least one metal element is solid-dissolved in zinc hydroxide. In addition, "aluminum dissolved in zinc hydroxide" refers to an aluminum element partially entering the crystal structure of zinc hydroxide.

Further, the mol % of zinc element and the mol % of aluminum element with respect to the total metal elements in the zinc composite hydroxide can be determined by, for example, ICP emission spectrometry (high frequency inductively coupled plasma emission spectrometry). More specifically, by ICP spectroscopic analysis, the ratio of the number of atoms of the zinc element to the total number of atoms of all the metal elements in the zinc composite hydroxide is defined as mol% of the zinc element, and the ratio of the number of atoms of the aluminum element can be obtained as mol % of elemental aluminum.

Moreover, when it further has "a metal element other than aluminum" to be described later, the mol % of this metal element can be obtained with respect to the total number of atoms of all the metal elements.

Note that the ICP emission spectroscopic analysis can be performed according to JIS K 0116:2014. Also, the analyzer is not particularly limited, and may be, for example, an ICP emission spectrometer SPS-3100 (Hitachi High-Tech Science).

In the zinc composite hydroxide, the zinc element is not particularly limited as long as it is 70.0 mol% or more with respect to the total metal elements in the zinc composite hydroxide, for example, 71.0 mol% or more, 72.0 mol % or more, 73.0 mol % or more, 74.0 mol % or more, 75.0 mol % or more, 76.0 mol % or more, 77.0 mol % or more, 78.0 mol % or more, 79.0 mol % or more, or 80.0 mol% or more, and 99.0 mol% or less, 95.0 mol% or less, 90.0 mol% or less, 85.0 mol% or less, 84.0 mol% or less, It may be 83.0 mol % or less, 82.0 mol % or less, 81.0 mol % or less, or 80.0 mol % or less.

Further, the aluminum element is not particularly limited as long as it is 30.0 mol% or less with respect to the total metal elements in the zinc composite hydroxide. 27.0 mol% or less, 26.0 mol% or less, 25.0 mol% or less, 24.0 mol% or less, 23.0 mol% or less, 22.0 mol% or less, 21.0 mol% or less, 20 0 mol % or less, 17.0 mol % or less, 15.0 mol % or less, or 12.0 mol % or less; It may be 0 mol % or more, or 11.0 mol % or more.

In the present disclosure, the zinc composite hydroxide may have a layered structure. In this case, zinc hydroxide and aluminum dissolved in zinc hydroxide can form the skeleton of the "host layer." Anions other than hydroxide ions can exist in a state of being inserted between the "host layers" (also referred to as "guest layers").

Here, the anion is not particularly limited as long as it is an anion other than hydroxide ion. Anions can be monovalent anions, divalent anions, or trivalent anions. More specifically, the anion may be, for example, at least one selected from the group consisting of carbonate anions, sulfate anions, and phosphate anions.

The anion present in the zinc composite hydroxide has a role of balancing the overall charge of the zinc composite hydroxide. Therefore, the anion content is not particularly limited, and can be appropriately adjusted, for example, according to the composition of the metal elements other than zinc, aluminum, and arbitrary aluminum described above.

In addition, the zinc composite hydroxide according to the present disclosure may further have (d) a metal other than aluminum dissolved in the zinc hydroxide.

In this case, the metal elements other than aluminum are preferably less than 20.0 mol%, and are 15.0 mol% or less and 12.0 mol% of the total metal elements in the zinc composite hydroxide. 10.0 mol% or less, 9.0 mol% or less, or 8.0 mol% or less; Alternatively, it may be 0.8 mol % or more.

The valence of the metal other than aluminum is preferably trivalent or higher, more specifically, for example, trivalent, tetravalent, pentavalent, or hexavalent, preferably trivalent or tetravalent. is more preferable.

Specific examples of metals other than aluminum include at least one selected from the group consisting of yttrium, titanium, zirconium, and molybdenum, preferably yttrium or zirconium.

In addition, the zinc composite hydroxide according to the present disclosure may further have water of crystallization. Water of crystallization can exist, for example, in a state of being inserted in the "guest layer" described above.

An example of the zinc composite hydroxide according to the present disclosure includes, for example, those represented by the following formula (I):
Zn _a Al _b M _c (A) _d (OH) _e (I)

In formula (I), M represents a metal element other than aluminum and has a valence of 3 or higher, and A represents an anion other than hydroxide. Here, the relationships: a+b+c=1, d>0, and e>0 are satisfied.

In addition, in formula (I), for example, a≧0.70, a≧0.75, or a≧0.80 may be satisfied. Also, b≦0.30, b≦0.25, or b≦0.20. Also, 0≦c<0.20 may be satisfied.

Zinc composite hydroxides according to the present disclosure also include, for example, those represented by formula (II) below:
Zn _a Al _b M _c (A) _d (OH) _e ·fH ₂ O (II)

In formula (II), symbols other than f can refer to formula (I) described above. Here, f represents a number obtained by normalizing the molar ratio of water of crystallization, and may be f>0.

(Negative electrode current collector)
The negative electrode current collector is not particularly limited, and may be, for example, a current collector having a three-dimensional mesh structure made of foam metal, expanded metal, punching metal, felt-like material of metal fibers, or the like. Moreover, the negative electrode current collector is preferably made of a material having electrical conductivity and alkali resistance. Specific examples of materials constituting the negative electrode current collector include, but are not limited to, copper, brass, steel, nickel, and the like.

Moreover, the shape of the negative electrode current collector is not particularly limited, and may be, for example, a plate shape or a sheet shape.

(other ingredients)
The negative electrode material may optionally contain other components such as, for example, conductive aids or binders.

The conductive aid is not particularly limited as long as it has conductivity and inhibits the electrode reaction. More specifically, examples of conductive aids include carbon materials, perovskite-type conductive materials, porous conductive polymers, metal porous bodies, and the like. The carbon material may or may not have a porous structure. Specific examples of carbon materials having a porous structure include mesoporous carbon and the like. On the other hand, examples of carbon materials having no porous structure include graphite, acetylene black, carbon nanotubes, carbon fibers, and the like.

The binder is not particularly limited, but is preferably one that enhances the binding strength of the active material and inhibits the electrode reaction. More specifically, examples of binders include fluoride polymers such as polyvinylidene fluoride (PVDF) and polytetrafluoroethylene (PTFE), and rubber resins such as styrene-butadiene rubber (SBR rubber). .

<Positive electrode>
In the present disclosure, a positive electrode includes a positive electrode material and a positive current collector. Here, the negative electrode material is not particularly limited, and can be appropriately set according to the intended alkaline battery. In the following, the positive electrode material will be described by taking the case of a nickel-zinc battery as an example. However, the alkaline battery of the present disclosure is not limited to this.

Further, the form of the positive electrode is not particularly limited, and for example, a negative positive electrode material is formed in layers on a plate-like positive electrode current collector, or a positive electrode in the form of a foam, particularly in the form of an open cell structure. A current collector coated or filled with a positive electrode material can be mentioned.

(Positive electrode active material)
The positive electrode material includes a positive electrode active material.

In nickel-zinc alkaline batteries, examples of the positive electrode active material include nickel hydroxide, nickel oxyhydroxide, and nickel composite hydroxide in which at least aluminum and ytterbium are dissolved in nickel hydroxide. It is not limited to these.

(Positive electrode current collector)
The positive electrode current collector is not particularly limited, and for example, the negative electrode current collector described above can be used as appropriate.

(other ingredients)
The positive electrode material may optionally contain other components such as, for example, conductive aids or binders. Regarding these other components, reference can be made to the "other components" that can be included in the negative electrode material described above.

<Alkaline electrolyte>
In the alkaline battery of the present disclosure, the alkaline electrolyte preferably contains the same anion as the anion in the zinc composite hydroxide contained as the negative electrode active material in the alkaline salt aqueous solution. In the following description, such anions contained in the alkaline electrolyte are also simply referred to as "homogeneous anions".

Through extensive research by the present inventors of the present disclosure, it was found that the alkaline electrolyte can further improve the discharge capacity when it contains the same type of anion as compared to when it does not contain the same type of anion. The reason is presumed as follows, but the present disclosure is not limited by this.

That is, it is presumed that the alkaline electrolyte containing the same kind of anions can suppress the elution of the anions in the zinc composite hydroxide, thereby suppressing the dissolution of the zinc composite hydroxide itself.

Alkaline salts constituting the alkaline electrolyte include, but are not limited to, potassium hydroxide (KOH), sodium hydroxide (NaOH), lithium hydroxide (LiOH), and the like.

The concentration of the alkali salt in the aqueous alkali salt solution may be, for example, 1 mol/L or more, 2 mol/L or more, 3 mol/L or more, 4 mol/L or more, 5 mol/L or more, or 6 mol/L or more, or 10 mol/L. /L or less, 9 mol/L or less, 8 mol/L or less, 7 mol/L or less, or 6 mol/L or less.

Moreover, the content of the same kind of anions in the alkaline electrolyte is not particularly limited. From the viewpoint of further exerting the effects of the present disclosure, the same kind of anion is preferably 0.1 mol or more with respect to 1 mol of hydroxide ions (OH ⁻ ) of the alkali salt in the alkaline electrolyte. , may be 0.2 mol or more, 0.3 mol or more, 0.4 mol or more, or 0.5 mol or more, and 1.0 mol or less, 0.8 mol or less, 0.7 mol or less, Alternatively, it may be 0.6 mol or less.

Also, according to the present disclosure, the alkaline electrolyte need not be saturated with zinc or zinc oxide. In other words, the alkaline battery of the present disclosure can solve the conventional zinc negative electrode problems by using the unique negative electrode active material and alkaline electrolyte of the present disclosure.

<Separator>
An alkaline battery of the present disclosure may have a separator.

The material of the separator is not particularly limited, and can be appropriately set according to the alkaline battery. Examples thereof include polyolefin nonwoven fabrics, polyethylene nonwoven fabrics, polypropylene nonwoven fabrics, polyamide nonwoven fabrics, polyethylene/polypropylene nonwoven fabrics, and hydrophilically treated nonwoven fabrics thereof.

<<Manufacturing method of alkaline battery>>
A method for manufacturing an alkaline battery according to the present disclosure may be, for example, a method including the following steps (i) to (iv):
(i) providing a negative electrode;
(ii) providing a positive electrode;
(iii) providing an alkaline electrolyte; and (iv) assembly.
<Step (i)>
In step (i), a negative electrode according to the present disclosure is prepared. Here, the negative electrode contains a zinc composite hydroxide having the following (a) to (c) as a negative electrode active material: (a) zinc hydroxide, (b) dissolved in zinc hydroxide aluminum, and (c) anions other than hydroxide ions.

Preparation of the zinc composite hydroxide contained as the negative electrode active material is not particularly limited, and a known method for preparing a layered composite hydroxide can be appropriately employed. An example will be described below.

First, a salt containing zinc and a salt containing aluminum are dissolved in water at a desired elemental composition ratio (molar ratio) to prepare a first solution.

Here, the zinc-containing salt is not particularly limited, and may be, for example, zinc sulfate, zinc nitrate, zinc chloride, or the like.

Moreover, the salt containing aluminum is not particularly limited, and may be, for example, aluminum sulfate, aluminum chloride, or aluminum nitrate.

In addition, when an arbitrary metal element other than aluminum is included, the salt containing the metal may be mixed at the desired elemental composition ratio (molar ratio) at the same time as the salt containing zinc and the salt containing aluminum described above. .

Next, a water-soluble alkaline substance is dissolved in water to prepare a second solution.

Here, the water-soluble alkaline substance is not particularly limited, and may be, for example, sodium hydroxide, calcium hydroxide, sodium carbonate, potassium carbonate, ammonium carbonate, sodium phosphate, or the like. Any of these water-soluble alkaline substances may be used alone, or two or more of them may be used in combination.

As anions other than hydroxide ions, carbonate anions are known to be preferentially inserted into the "guest layer" of zinc composite hydroxide.

Therefore, when carbonate anions are intended as anions other than hydroxide ions, a water-soluble alkaline substance containing carbonate anions such as sodium carbonate is used alone when preparing the second solution. It may be used in combination with other water-soluble alkaline substances such as sodium hydroxide.

Moreover, when anions other than carbonate anions such as sulfate anions and phosphate anions are intended as anions other than hydroxide ions, it is preferable not to contain carbonate anions.

More specifically, for example, when a sulfate anion is used as an anion other than a hydroxide ion, another water-soluble alkaline substance not containing a carbonate anion (for example, sodium hydroxide) is dissolved in water as the second solution. may be prepared by In this case, if a zinc or aluminum salt containing a sulfate anion is employed when preparing the above-described first solution, the sulfate anion can be inserted into the zinc composite hydroxide.

Further, for example, when a phosphate anion is used as an anion other than a hydroxide ion, another water-soluble alkaline substance containing no carbonate anion and containing a phosphate anion (for example, sodium phosphate, etc.) is used as the second solution. may be prepared by dissolving in water alone or in combination with other water-soluble alkaline substances such as sodium hydroxide.

The method for introducing (c) anions other than hydroxide ions into the zinc composite hydroxide is not limited to the above, and can be appropriately designed by those skilled in the art.

Then, the first solution and the second solution are mixed in a reaction vessel to obtain a slurry. This slurry is placed in an apparatus such as an autoclave and heated at a temperature of 150° C. to 200° C. or 160° C. to 170° C. for several hours (for example, 2 hours or more).

After heating, it is cooled to room temperature and normal work-up is carried out. For example, the target zinc composite hydroxide can be prepared by operations such as filtering, washing, and drying.

The composition ratio (molar ratio) of zinc, aluminum, and any metal element other than aluminum in the zinc composite hydroxide is adjusted according to the target molar ratio when preparing the first solution. A solution containing metal ions may be mixed.

The resulting zinc composite hydroxide, optionally other components such as a conductive aid or a binder, and water are mixed to prepare a negative electrode material slurry.

A negative electrode can be prepared by applying or filling this negative electrode material slurry to a negative electrode current collector, drying and/or baking, and compressing.

<Step (ii)>
In step (ii), a positive electrode is prepared.

The positive electrode can be produced by a method known in the art according to the intended alkaline battery. The manufacturing process of the positive electrode can be performed in the same manner as the manufacturing process of the negative electrode, except that materials for the positive electrode current collector and the positive electrode material are used, for example.

<Step (iii)>
In step (iii), an alkaline electrolyte is prepared. Here, the alkaline electrolyte contains anions of the same kind as the anions in the zinc composite hydroxide.

<Step (iv)>
In step (iv), the prepared positive and negative electrodes and the separator are assembled.
A laminate is produced by interposing a separator between the positive electrode and the negative electrode. Thereby, a laminate in which the positive electrode, the separator, and the negative electrode are laminated in this order can be obtained.

On the other hand, the alkaline battery of the present disclosure can be manufactured by injecting the prepared alkaline electrolyte into a housing that serves as the exterior of the battery, and immersing the previous laminate in the restrained case.

<<Example 1>>
(Preparation of negative electrode)
A first solution was prepared by dissolving zinc sulfate and aluminum sulfate in pure water at a molar ratio of zinc:aluminum=80:20.

A second solution was prepared by dissolving sodium hydroxide and sodium carbonate in pure water.

The first solution and the second solution prepared above were mixed and neutralized in a reactor, and the resulting slurry was transferred to an autoclave and reacted at 170° C. for 2 hours.

The reaction system was then cooled to room temperature and the product was filtered off and washed with pure water. After that, by drying with hot air, a powdery zinc composite hydroxide was obtained as a negative electrode active material.

In the zinc composite hydroxide of Example 1, aluminum is dissolved in zinc hydroxide. According to the measurement results of ICP emission spectrometry (ICP emission spectrometry SPS-3100 (Hitachi High-Tech Science) device), all metal elements in the zinc composite hydroxide of Example 1 (sum of zinc and aluminum elements) , the zinc element was 80.0 mol% or more, and the aluminum element was 20.0 mol%. In addition, the zinc composite hydroxide of Example 1 contained carbonate anions as anions other than hydroxide ions.

Then, by mixing with pure water in an amount such that the solid content weight ratio of the zinc composite hydroxide powder of Example 1: acetylene black: styrene-butadiene rubber = 85: 10: 5, a negative electrode material slurry was obtained. made.

A negative electrode was prepared by applying this negative electrode material slurry to a metal current collector, drying it, and then compressing it.

(Preparation of positive electrode)
A positive electrode material slurry was prepared by mixing pure water in an amount of nickel hydroxide: acetylene black: styrene-butadiene rubber = 85:10:5 in solid content weight ratio.

A positive electrode was prepared by applying this positive electrode material slurry to a metal current collector, drying it, and then compressing it.

(Preparation of alkaline electrolyte)
A 6 mol/L potassium hydroxide aqueous solution was prepared as an alkaline electrolyte.

(assembly)
An acrylic plate, a negative electrode, a separator, a positive electrode, a separator, a negative electrode, and an acrylic plate were laminated in this order, and a laminate was produced by pressing them together with screws. A polyethylene/polyolefin nonwoven fabric composed of polyethylene and polypropylene was used as the material of the separator.

The thus produced laminate was impregnated in an acrylic container containing the alkaline electrolyte prepared above, and an Hg/HgO electrode as a reference electrode was arranged near the laminate, thereby producing the alkaline battery of Example 1. made.

<<Example 2>>
In the same manner as in Example 1, except that 10 mol% of aluminum was reduced based on the composition of zinc and aluminum in Example 1 described above, and 10 mol% of yttrium was dissolved. An alkaline battery of Example 2 was produced.

In the zinc composite hydroxide of Example 2, aluminum and yttrium are dissolved in zinc hydroxide. According to the measurement results of ICP emission spectrometry (ICP emission spectrometry SPS-3100 (Hitachi High-Tech Science)), all metal elements in the zinc composite hydroxide of Example 2 (zinc element, aluminum element, and yttrium element ), the zinc element was 80.0 mol % or more, the aluminum element was 12.0 mol %, and the yttrium element was 8.0 mol %. In addition, the zinc composite hydroxide of Example 2 contained carbonate anions as anions other than hydroxide ions.

<<Example 3>>
Based on the composition of zinc and aluminum in Example 1 described above, the same procedure as in Example 1 was performed except that 10 mol% of aluminum was reduced and 10 mol% of zirconium was dissolved. , an alkaline battery of Example 3 was produced.

In the zinc composite hydroxide of Example 3, aluminum and zirconium are dissolved in zinc hydroxide. According to the measurement results of ICP emission spectrometry (ICP emission spectrometer SPS-3100 (Hitachi High-Tech Science)), all metal elements in the zinc composite hydroxide of Example 3 (zinc element, aluminum element, and zirconium element ), the zinc element was 78.4 mol% or more, the aluminum element was 11.8 mol%, and the zirconium element was 9.8 mol%. In addition, the zinc composite hydroxide of Example 3 contained carbonate anions as anions other than hydroxide ions.

<<Example 4>>
An alkaline battery of Example 4 was produced in the same manner as in Example 1, except that a mixed solution of a 6 mol/L aqueous potassium hydroxide solution and a 3 mol/L aqueous potassium carbonate solution was prepared in the preparation of the alkaline electrolyte. did.

<<Example 5>>
An alkaline battery of Example 5 was produced in the same manner as in Example 2, except that a mixed solution of a 6 mol/L aqueous potassium hydroxide solution and a 3 mol/L aqueous potassium carbonate solution was prepared in the preparation of the alkaline electrolyte. did.

<<Example 6>>
An alkaline battery of Example 6 was produced in the same manner as in Example 3, except that a mixed solution of a 6 mol/L aqueous potassium hydroxide solution and a 3 mol/L aqueous potassium carbonate solution was prepared in the preparation of the alkaline electrolyte. did.

<<Example 7>>
An alkaline battery of Example 7 was produced in the same manner as in Example 1, except that the second solution was prepared without using sodium carbonate in the preparation of the negative electrode active material.

In the zinc composite hydroxide of Example 7, aluminum is dissolved in zinc hydroxide. According to the measurement results of ICP emission spectrometry (ICP emission spectrometry SPS-3100 (Hitachi High-Tech Science)), the total metal elements (the total of zinc and aluminum elements) in the zinc composite hydroxide of Example 7 On the other hand, the zinc element was 80.0 mol % or more, and the aluminum element was 20.0 mol %. In addition, the zinc composite hydroxide of Example 7 contained sulfate anions as anions other than hydroxide ions.

<<Example 8>>
An alkaline battery of Example 8 was prepared in the same manner as in Example 7, except that a mixed solution of a 6 mol/L aqueous potassium hydroxide solution and a 0.7 mol/L aqueous potassium sulfate solution was prepared in the preparation of the alkaline electrolyte. was made.

<<Example 9>>
An alkaline battery of Example 9 was produced in the same manner as in Example 1, except that trisodium phosphate was used in place of sodium carbonate in the preparation of the negative electrode active material to prepare the second solution.

In the zinc composite hydroxide of Example 9, aluminum is dissolved in zinc hydroxide. According to the measurement results of ICP emission spectrometry (ICP emission spectrometer SPS-3100 (Hitachi High-Tech Science)), the total metal elements (the total of zinc and aluminum elements) in the zinc composite hydroxide of Example 9 On the other hand, the zinc element was 78.4 mol % or more, and the aluminum element was 21.6 mol %. In addition, the zinc composite hydroxide of Example 9 contained phosphate anions as anions other than hydroxide ions.

<<Example 10>>
An alkaline battery of Example 10 was prepared in the same manner as in Example 9, except that a mixed solution of a 6 mol/L aqueous potassium hydroxide solution and a 3 mol/L aqueous potassium phosphate solution was prepared in the preparation of the alkaline electrolyte. made.

<<Example 11>>
Example 11 was carried out in the same manner as in Example 1, except that 5 mol% of zinc was reduced and 5 mol% of aluminum was increased based on the composition of zinc and aluminum in Example 1 described above. of alkaline batteries were produced.

In the zinc composite hydroxide of Example 11, aluminum is dissolved in zinc hydroxide. According to the measurement results of ICP emission spectrometry (ICP emission spectrometry SPS-3100 (Hitachi High-Tech Science)), the total metal elements (the total of zinc and aluminum elements) in the zinc composite hydroxide of Example 11 On the other hand, the zinc element was 74.1 mol % or more, and the aluminum element was 25.9 mol %. In addition, the zinc composite hydroxide of Example 11 contained carbonate anions as anions other than hydroxide ions.

<<Example 12>>
An alkaline battery of Example 12 was produced in the same manner as in Example 11, except that a mixed solution of a 6 mol/L aqueous potassium hydroxide solution and a 3 mol/L aqueous potassium carbonate solution was prepared in the preparation of the alkaline electrolyte. did.

<<Comparative example 1>>
An alkaline battery of Comparative Example 1 was produced in the same manner as in Example 1, except that zinc oxide was used as the negative electrode active material instead of the zinc composite hydroxide powder of Example 1.

<<Comparative Example 2>>
Comparative Example 2 was carried out in the same manner as in Example 1 except that 13 mol% of zinc was reduced and 13 mol% of aluminum was increased based on the composition of zinc and aluminum in Example 1 described above. of alkaline batteries were produced.

In the zinc composite hydroxide of Comparative Example 2, aluminum is dissolved in zinc hydroxide. According to the measurement results of ICP emission spectrometry (ICP emission spectrometry SPS-3100 (Hitachi High-Tech Science)), the total metal elements (the total of zinc and aluminum elements) in the zinc composite hydroxide of Comparative Example 2 On the other hand, the zinc element was 67.0 mol % or more, and the aluminum element was 33.0 mol %. In addition, the zinc composite hydroxide of Comparative Example 2 contained carbonate anions as anions other than hydroxide ions.

Details of each example and comparative example produced are shown in Table 1 below.

"evaluation"
<Battery charge/discharge evaluation>
The batteries of Examples and Comparative Examples prepared above were set in a constant temperature bath at 25° C., and charge/discharge evaluation was performed.

More specifically, the theoretical capacity was set to 100%, and the battery was charged for 5 hours at a current load of 5 hour rate. A rest period of 10 minutes was provided. After that, discharge was performed with the same current load until the terminal voltage reached -0.1V.

<result>
The results of Example 1, Comparative Examples 1 and 2 are shown in FIG. 1, the results of Examples 1-3 are shown in FIG. 2, the results of Examples 4-6 are shown in FIG. 4, the results of Examples 9 and 10 are shown in FIG. 5, and the results of Examples 11 and 12 are shown in FIG.

As is apparent from the results of FIG. 1, the comparison using the alkaline battery of Comparative Example 1 using a conventional zinc oxide negative electrode and the zinc composite hydroxide outside the specific mol % range of the present disclosure It was found that the alkaline battery of Example 1 had a larger discharge capacity than the alkaline battery of Example 2.

1 to 6, it was found that the alkaline batteries of Examples 1 to 12 had higher discharge capacities than the alkaline batteries of Comparative Examples 1 and 2.

Further, from a comparison of the results of Examples 1 to 3 in FIG. 2 and Examples 4 to 6 in FIG. 3, the same anion as the anion in the zinc composite hydroxide is present in the alkaline electrolyte. It was found that the alkaline batteries of Examples 4-6, respectively, had improved discharge capacities over the alkaline batteries of Examples 1-3, which did not have this same kind of anion. Similarly, comparison of the results of Examples 7 and 8 in FIG. 4, comparison of the results of Examples 9 and 10 in FIG. 5, and comparison of the results of Examples 11 and 12 in FIG. From the comparison also, the alkaline batteries of Examples 8, 10 and 12, in which the same kind of anion as the anion in the zinc composite hydroxide is present in the alkaline electrolyte, are the same as those in Example 7, in which the same kind of anion is not present. , 9 and 11, the discharge capacity was improved.

Claims (8)

An alkaline battery having a negative electrode, a positive electrode, and an alkaline electrolyte,
The negative electrode contains, as a negative electrode active material, a zinc composite hydroxide having the following (a) to (c): (a) zinc hydroxide, (b) aluminum dissolved in the zinc hydroxide and (c) anions other than hydroxide ions,
The anion is at least one selected from the group consisting of a carbonate anion, a sulfate anion, and a phosphate anion,
The zinc element is 70.0 mol% or more and the aluminum element is 30.0 mol% or less with respect to the total metal elements in the zinc composite hydroxide, and the alkaline electrolyte is the same kind as the anion containing the anion of
alkaline battery. 2. The alkaline battery according to claim 1, wherein in the alkaline electrolyte, the same kind of anion is 0.1 mol or more per 1 mol of hydroxide ion of the alkali salt. An alkaline battery having a negative electrode, a positive electrode, and an alkaline electrolyte,
The negative electrode contains, as a negative electrode active material, a zinc composite hydroxide having the following (a) to (c): (a) zinc hydroxide, (b) aluminum dissolved in the zinc hydroxide and (c) anions other than hydroxide ions,
The anion is at least one selected from the group consisting of a carbonate anion, a sulfate anion, and a phosphate anion,
The zinc element is 70.0 mol% or more and the aluminum element is 30.0 mol% or less with respect to the total metal elements in the zinc composite hydroxide, and the zinc composite hydroxide contains (d ) further has a metal element other than aluminum dissolved in the zinc hydroxide,
The valence of the metal element other than aluminum is 3 or more, and the metal element other than aluminum is less than 20.0 mol% with respect to the total metal elements in the zinc composite hydroxide.
alkaline battery. 4. The alkaline battery according to claim 3, wherein said metal element other than aluminum is at least one selected from the group consisting of yttrium, titanium, zirconium and molybdenum. An alkaline battery having a negative electrode, a positive electrode, and an alkaline electrolyte,
The negative electrode contains, as a negative electrode active material, a zinc composite hydroxide having the following (a) to (c): (a) zinc hydroxide, (b) aluminum dissolved in the zinc hydroxide and (c) anions other than hydroxide ions,
The anion is at least one selected from the group consisting of a carbonate anion, a sulfate anion, and a phosphate anion,
The zinc element is 70.0 mol% or more and the aluminum element is 30.0 mol% or less with respect to the total metal elements in the zinc composite hydroxide, and the alkaline electrolyte is zinc or zinc oxide not saturated with,
alkaline battery. The alkaline battery according to any one of claims 1 to 5 , wherein the zinc composite hydroxide further contains water of crystallization. The alkaline battery according to any one of claims 1 to 6 , wherein the positive electrode contains nickel hydroxide as a positive electrode active material. The alkaline battery according to any one of claims 1 to 7 , which is a secondary battery.

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