JP2003173779A - Battery negative electrode and alkaline battery - Google Patents

Abstract

(57) [Problem] To provide an alkaline battery capable of improving discharge characteristics in a heavy load region. A battery 1 is an alkaline battery including a positive electrode 3, a negative electrode 5, and a separator 4. This negative electrode 5
Contains particulate zinc, aqueous alkaline solution, and gelling agent. This gelling agent has an average particle size (D) after swelling of 1.6.
mm ≦ D ≦ 1.9 mm, and the volume ratio (R) after swelling is 5.5% ≦ R ≦ 12.0%. The gelling agent is made of a superabsorbent polymer. This superabsorbent polymer is composed of a crosslinked polyacrylic acid or a crosslinked polyacrylate.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a negative electrode for a battery. The present invention also relates to an alkaline battery using this negative electrode for a battery.

[0002]

2. Description of the Related Art With the recent development of portable electronic devices, a battery as a power source can draw a larger current, and
What can be used for a longer period of time has been demanded. Therefore, efforts have been made to reduce the internal resistance of the battery in order to enable heavy load discharge.

For example, by applying a conductive coating material to the inside of a battery can, the adhesion between the positive electrode and the battery can is increased to reduce the contact resistance, and the separator has good ionic conductivity and good electrical conductivity. I have chosen one.

Also in the negative electrode, attempts have been made to change the zinc blending ratio to reduce the internal resistance and to modify the zinc surface to increase the contact area between zinc and the electrolytic solution.

[0005]

However, if the ratio of zinc is increased, the ratio of the electrolytic solution to zinc is decreased and the discharge characteristics are deteriorated. Especially in the heavy load region which is currently demanded, the phenomenon is remarkable.

In addition, when the surface of zinc is modified to increase the surface area with the electrolytic solution, although it is effective for heavy load discharge characteristics, zinc is corroded during storage of the battery and gas is generated. As a result, there is a problem that it has not been put to practical use because the liquid leakage resistance is deteriorated.

The present invention has been made in view of the above problems, and it is an object of the present invention to provide a negative electrode for a battery capable of improving discharge characteristics in a heavy load region, and an alkaline battery using the negative electrode for the battery. To aim.

[0008]

The battery negative electrode of the present invention comprises:
A negative electrode for use in an alkaline battery, comprising a granular zinc, an alkaline aqueous solution, and a battery negative electrode containing a gelling agent,
The gelling agent has an average particle size (D) of 1.6 mm after swelling.
≦ D ≦ 1.9 mm, and the gelling agent is
The volume ratio (R) after swelling is in the range of 5.5% ≦ R ≦ 12.0%.

Here, the mass ratio (GE) of the gelling agent before swelling to the alkaline aqueous solution is 2.5 ≦ GE ≦ 4.0.
It is preferably in the range of. Further, the gelling agent preferably comprises a super absorbent polymer. Further, the super absorbent polymer preferably comprises crosslinked polyacrylic acid or crosslinked polyacrylic acid salt. Further, the cross-linked polyacrylic acid salt is preferably a sodium salt.

Further, the alkaline battery of the present invention comprises a positive electrode, a negative electrode, and a separator, and the negative electrode is granular zinc,
In an alkaline battery containing an alkaline aqueous solution and a gelling agent, the gelling agent has an average particle size (D) after swelling in a range of 1.6 mm ≦ D ≦ 1.9 mm, and the gelling agent is , The volume ratio (R) after swelling is 5.5% ≦ R ≦ 1
It is in the range of 2.0%.

Here, the mass ratio (GE) of the gelling agent before swelling to the alkaline aqueous solution is 2.5 ≦ GE ≦ 4.0.
It is preferably in the range of. Further, the gelling agent preferably comprises a super absorbent polymer. Further, the super absorbent polymer preferably comprises crosslinked polyacrylic acid or crosslinked polyacrylic acid salt. Further, the cross-linked polyacrylic acid salt is preferably a sodium salt.

According to the battery negative electrode and the alkaline battery of the present invention, the average particle diameter (D) of the gelling agent after swelling is 1.6 m.
When the volume ratio (R) of the gelling agent after swelling is within the range of m ≦ D ≦ 1.9 mm and within the range of 5.5% ≦ R ≦ 12.0%, the zinc is locally dense. Since the portion holding the electrolytic solution is formed, the zinc network can be secured, and the contact area between the zinc powder and the electrolytic solution can be sufficiently secured.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below. First, the battery negative electrode used in the alkaline battery will be described. This battery negative electrode contains granular zinc, an alkaline aqueous solution, and a gelling agent. less than,
The granular zinc, alkaline aqueous solution, and gelling agent will be described.

First, the granular zinc will be described. Granular zinc is composed of fine particles of zinc metal. Here, the average particle size of the granular zinc is preferably in the range of 150 to 300 μm. If the average particle size is within this range,
This is because it has the advantages that it is unlikely to be affected by the corrosion of zinc and that discharge with a heavy load becomes possible.

The particle size distribution of the granular zinc is 50 to 450.
It is preferably in the range of μm. This is because when the particle size distribution is within this range, there is an advantage that it is unlikely to be affected by zinc corrosion and that a heavy load discharge becomes possible.

The volume ratio of granular zinc is 23 to 31%.
It is preferably in the range of. This is because when the volume ratio is within this range, there is an advantage that the zinc network is good and it becomes possible to secure the electrolytic solution necessary for heavy load discharge.

Here, the volume ratio of the granular zinc is a value in which the volume of the granular zinc is expressed as a percentage of the volume of the gelled negative electrode prepared from the negative electrode constituents such as the granular zinc, the alkaline aqueous solution, and the gelling agent. is there.

Next, the alkaline aqueous solution which is a constituent of the negative electrode will be described. A potassium hydroxide aqueous solution can be used as the alkaline aqueous solution. The concentration of the aqueous potassium hydroxide solution is preferably in the range of 30 to 45% by mass. This is because when the concentration is within this range, there is an advantage that the conductivity of the electrolytic solution required for heavy load discharge characteristics can be secured.

The alkaline aqueous solution is not limited to the above-mentioned potassium hydroxide aqueous solution. In addition, an aqueous solution of sodium hydroxide, an aqueous solution of lithium hydroxide or the like can be adopted.

Next, the gelling agent which is another constituent of the negative electrode will be described. A super absorbent polymer can be used as the gelling agent.

The superabsorbent polymer will be described below. First, the material of the superabsorbent polymer will be described.
The material of the superabsorbent polymer is preferably crosslinked polyacrylic acid or crosslinked polyacrylate. Further, the cross-linked polyacrylic acid salt is preferably a sodium salt. The term "crosslinked" means that the polymer has a three-dimensional network structure due to crosslinking.

The material of the superabsorbent polymer is not limited to the above-mentioned crosslinked polyacrylic acid or crosslinked polyacrylate. As the material of the superabsorbent polymer, one having excellent liquid retaining property of the electrolytic solution, good ionic conductivity, low electric resistance, and stable to the alkaline electrolytic solution can be adopted. Specifically, starch-graft copolymer system, polyvinyl alcohol system, polyvinyl alcohol-
Polymers such as polyacrylic acid salt-based, polyacrylamide-based, isobutylene-maleic acid copolymer-based, and cellulose-based polymers can be adopted.

Further, the cross-linked polyacrylic acid salt is not limited to the above-mentioned sodium salt. As the cross-linked polyacrylic acid salt, potassium salt, lithium salt and the like can be adopted.

The average particle size of the gelling agent (hereinafter referred to as "gelling agent after swelling") that is present in the gelled negative electrode prepared by mixing the constituents of the negative electrode and is absorbing the alkaline aqueous solution. The diameter (D) is preferably in the range of 1.6 to 1.9 mm. This is because when the average particle diameter (D) is within this range, there is an advantage that a proper electrolyte can be supplied while maintaining a good network of zinc powders when properly dispersed in the negative electrode.

The particle size distribution of the gelling agent after swelling is 0.
It is preferably in the range of 6 to 2.8 mm. This is because when the particle size distribution is within this range, it is possible to supply a sufficient electrolytic solution while maintaining a good network of zinc powders when properly dispersed in the negative electrode.

The particle size of the gelling agent after swelling was measured by the following method. After adding 1 g of the gelling agent to 200 g of the electrolytic solution and stirring, the mixture is left for 3 days. After this, the gelling agent was taken out and the particle size was measured with a microscope equipped with a scale.

Next, the electrolyte absorption amount of the superabsorbent polymer is preferably in the range of 25 to 65 g / g. This is because when the electrolyte absorption amount is within this range, there is an advantage that the gelling agent does not appropriately contact the zinc powder and interfere with the heavy load discharge reaction. The amount of electrolyte absorbed is
The maximum mass of an electrolyte solution that can be absorbed by a unit mass of superabsorbent polymer.

The mass ratio (GE) of the starting gelling agent (hereinafter referred to as "gelling agent before swelling") to the alkaline aqueous solution is preferably in the range of 2.5 to 4.0. This is because when the mass ratio is within this range, there is an advantage that the gelling agent can appropriately contact the zinc powder and supply a necessary amount of the electrolytic solution to the zinc powder.

The volume ratio (R) of the gelling agent after swelling
Is preferably in the range of 5.5 to 12.0%. This is because when the volume ratio (R) is within this range, there is an advantage that the network of zinc powders can be kept good and the electrolytic solution necessary for the reaction can be promptly supplied.

Here, the volume ratio (R) of the gelling agent after swelling means the volume ratio (R) of the gelling negative electrode prepared from negative electrode constituents such as granular zinc, an aqueous alkaline solution, and a gelling agent after swelling. It is a value in which the volume of the gelling agent is expressed in percentage.

Next, an alkaline battery using the above-mentioned battery negative electrode will be described. FIG. 1 is a cross-sectional view showing an alkaline manganese battery as one configuration example of the alkaline battery. That is, this battery 1 is a battery having a positive electrode using manganese dioxide as a positive electrode active material and a negative electrode using zinc as a negative electrode active material.

Specifically, the battery 1 includes a battery can 2 and
A positive electrode 3, a separator 4, a negative electrode 5, a sealing member 6,
The washer 7, the negative electrode terminal plate 8, and the collector pin 9 are provided.

Here, the battery can 2 is a bottomed cylindrical metal can having an opening. The battery can 2 is, for example, iron plated with nickel and serves as an external positive electrode terminal of the battery.

The positive electrode 3 has a hollow cylindrical shape, and contains a positive electrode mixture composed of manganese dioxide, which is a positive electrode active material, graphite powder, which is a conductive agent, and aqueous potassium hydroxide solution, which is an electrolytic solution, in a hollow cylindrical shape. Formed into positive electrode pellets 3a, 3b,
3 c is laminated inside the battery can 2.

The separator 4 is in the shape of a cylinder having a thin wall thickness, one end is closed, and the other end has an opening. The separator 4 is arranged so as to contact the inside of the positive electrode 3.

As described above, the negative electrode 5 has granular zinc as a negative electrode active material, an electrolytic solution using an aqueous solution of potassium hydroxide, and the negative electrode 5 is gelled to uniformly disperse the granular zinc and the electrolytic solution. It consists of a gelling agent and the like. This negative electrode 5
Are injected into the bottomed cylindrical separator 4.

Then, the opening of the battery can 2 in which the positive electrode 3 and the separator 4 filled with the negative electrode 5 are housed is
A sealing member 6 is fitted to seal this opening. The sealing member 6 is made of a plastic material, and a washer 7 and a negative electrode terminal plate 8 are attached so as to cover the sealing member 6.

Further, a brass current collecting pin 9 is press-fitted into the through hole of the sealing member 6 to which the washer 7 is attached from above. Thereby, the current collection of the negative electrode is ensured by the nail-shaped current collection pin 9 welded to the negative electrode terminal plate 8 being pressed into the through hole formed in the central portion of the sealing member 6 and reaching the negative electrode. There is. The positive electrode current collection is ensured by connecting the positive electrode 3 and the battery can 2. The outer peripheral surface of the battery can 2 is covered with an exterior label (not shown), and the positive electrode terminal is located below the battery can 2.

Generally, in the gelled negative electrode, when the zinc composition is decreased to increase the electrolytic solution composition, the zinc composition in the gelled negative electrode is decreased and the zinc-zinc network is weakened. As a result, it is known that the internal resistance of the battery rises and the discharge characteristics deteriorate. Further, when the gelling agent volume in the gelled negative electrode is low, the electrolytic solution and the granular zinc are separated. As a result, the contact area between the electrolytic solution and the zinc powder decreases, and the discharge characteristics deteriorate.

Therefore, the average particle size (D) of the gelling agent after swelling is in the range of 1.6 mm≤D≤1.9 mm, and the volume ratio (R) of this gelling agent in the negative electrode is 5%. ．
By using a gelled negative electrode with 5% ≤ R ≤ 12.0%, an electrolyte solution is appropriately retained, and a zinc dense local portion and a portion retaining the electrolyte solution are formed. And the contact area between the granular zinc and the electrolytic solution can be sufficiently secured. As a result, a battery having a low internal resistance can be manufactured, and discharge characteristics in a heavy load region can be improved.

Although the alkaline manganese battery has been described in the present embodiment, the present invention can be applied to the same alkaline battery system such as nickel cadmium battery, air zinc battery, nickel zinc battery, nickel hydrogen battery and silver oxide battery. .

In the present embodiment, the alkaline manganese battery which is the primary battery has been described, but the present invention is not limited to this primary battery, and the present invention can be applied to other secondary batteries.

In the present embodiment, a cylindrical alkaline manganese battery has been described, but the present invention is not limited to this cylindrical battery, and the present invention can be applied to other flat batteries such as flat batteries. Of course, it can be applied. Moreover, the battery size is not particularly limited.

Further, the present invention is not limited to the above-mentioned embodiments, and it goes without saying that various other configurations can be adopted without departing from the gist of the present invention.

[0045]

EXAMPLES Next, examples of the present invention will be specifically described. However, it goes without saying that the present invention is not limited to these examples.

First, a method of manufacturing the sample battery will be described. For AA alkaline manganese batteries, batteries of Conventional Example, Example, and Comparative Example were prepared below.

Conventional Example As shown in FIG. 1, the conventional battery has a closed lower end and a cylindrical battery can 2 having an opening at the upper end, in which manganese dioxide, graphite powder, and A positive electrode pellet 3a obtained by molding a positive electrode mixture composed of an aqueous potassium hydroxide solution (concentration: 40% by mass) into a hollow cylindrical shape,
A positive electrode 3 in which 3b and 3c are stacked is arranged.

Next, a gelled negative electrode 5 was prepared. The raw materials for the gelled negative electrode 5 are as follows. That is, granular zinc (average particle size: 200 μm, particle size distribution: 75
˜425 μm), an aqueous potassium hydroxide solution (concentration: 40% by mass), a gelling agent (crosslinked sodium polyacrylate, electrolyte solution absorption amount: 30 g / g) and the like. here,
The mass ratio (GE) of the gelling agent before swelling to the alkaline aqueous solution is 2.3.

The gelled negative electrode 5 is incorporated inside the positive electrode 3 via the separator 4 made of a non-woven fabric. here,
The volume ratio of granular zinc in the gelled negative electrode 5 is 26%.
Is. Further, in the gelled negative electrode 5, the average particle size (D) of the gelling agent after swelling is 1.35 mm, the particle size distribution is 0.9 to 1.8 mm, and the volume ratio (R) is 4. .8
%.

The outer peripheral surface of the cylinder of the battery can 2 is covered with an exterior label (not shown), and the positive electrode terminal is located below the battery can 2. A sealing body is fitted in the opening of the battery can 2. The sealing body is the negative electrode terminal plate 8, the sealing member 6,
The sealing member 6 is made of a plastic material, and the washer 7 and the negative electrode terminal plate 8 are attached so as to cover the sealing member 6. Further, a brass current collecting pin 9 is press-fitted into the through hole of the sealing member 6 into which the reinforcing member is fitted from above.

Example 1 In the battery of Example 1,
The average particle size (D) of the gelling agent after swelling in the gelled negative electrode was 1.6 mm, and the particle size distribution was 1.0 to 2.0.
mm, and the volume ratio (R) of the gelling agent is 5.5%. The mass ratio (GE) of the gelling agent before swelling is 2.
It is 5. Others are the same as the conventional example.

Example 2 In the battery of Example 2,
The average particle size (D) of the gelling agent after swelling in the gelled negative electrode was 1.6 mm, and the particle size distribution was 1.0 to 2.0.
mm, and the volume ratio (R) of the gelling agent is 12%. Further, the mass ratio (GE) of the gelling agent is 4.0. Others are the same as the conventional example.

Example 3 In the battery of Example 3,
The average particle size (D) after swelling of the gelling agent in the gelled negative electrode was 1.9 mm, and the particle size distribution was 1.0 to 2.5.
mm, and the volume ratio (R) of the gelling agent is 5.5%. Further, the mass ratio (GE) of the gelling agent is 2.5. Others are the same as the conventional example.

Example 4 In the battery of Example 4,
Cross-linked polyacrylic acid as gelling agent (electrolyte solution absorption:
34 g / g) was used. In the gelled negative electrode 5, the average particle size (D) of the gelling agent after swelling was 1.9 mm, the particle size distribution was 0.6 to 2.8 mm, and the volume ratio (R) was 12. %. Further, the mass ratio of the gelling agent (G
E) is 4.0. Others are the same as the conventional example.

Comparative Example 1 In the battery of Comparative Example 1,
The average particle size (D) of the gelling agent after swelling in the gelled negative electrode was 1.1 mm, and the particle size distribution was 0.6 to 1.5.
mm, and the volume ratio (R) of the gelling agent is 5.5%. Further, the mass ratio (GE) of the gelling agent is 2.5. Others are the same as the conventional example.

Comparative Example 2 In the battery of Comparative Example 2,
The average particle size (D) of the gelling agent after swelling in the gelled negative electrode was 1.1 mm, and the particle size distribution was 0.6 to 1.5.
mm, and the volume ratio (R) of the gelling agent is 12%. Further, the mass ratio (GE) of the gelling agent is 4.0. Others are the same as the conventional example.

Comparative Example 3 In the battery of Comparative Example 3,
The average particle size (D) of the gelling agent in the gelled negative electrode after swelling was 2.2 mm, and the particle size distribution was 1.7 to 2.8.
mm, and the volume ratio (R) of the gelling agent is 5.5%. Further, the mass ratio (GE) of the gel agent is 2.5.
Others are the same as the conventional example.

Comparative Example 4 In the battery of Comparative Example 4,
The average particle size (D) of the gelling agent in the gelled negative electrode after swelling was 2.2 mm, and the particle size distribution was 1.7 to 2.8.
mm, and the volume ratio (R) of the gelling agent is 12%. Further, the mass ratio (GE) of the gel agent is 4.0.
Others are the same as the conventional example.

Comparative Example 5 In the battery of Comparative Example 5,
The average particle size (D) of the gelling agent after swelling in the gelled negative electrode was 1.6 mm, and the particle size distribution was 1.0 to 2.0.
mm, and the volume ratio (R) of the gelling agent is 3%.
The mass ratio (GE) of the gelling agent is 1.8. Others are the same as the conventional example.

[Comparative Example 6] In the battery of Comparative Example 6,
The average particle size (D) after swelling of the gelling agent in the gelled negative electrode was 1.9 mm, and the particle size distribution was 1.0 to 2.5.
mm, and the volume ratio (R) of the gelling agent is 3%.
The mass ratio (GE) of the gelling agent is 1.8. Others are the same as the conventional example.

[Comparative Example 7] In the battery of Comparative Example 7,
The average particle size (D) of the gelling agent after swelling in the gelled negative electrode was 1.6 mm, and the particle size distribution was 1.0 to 2.0.
mm, and the volume ratio (R) of the gelling agent is 15%. The mass ratio (GE) of the gelling agent is 4.4. Others are the same as the conventional example.

Comparative Example 8 In the battery of Comparative Example 8,
The average particle size (D) of the gelling agent in the gelled negative electrode after swelling was 2.2 mm, and the particle size distribution was 1.7 to 2.8.
mm, and the volume ratio (R) of the gelling agent is 15%. The mass ratio (GE) of the gelling agent is 4.4. Others are the same as the conventional example.

Next, the battery characteristics of the battery manufactured by the above method were evaluated. First, 1500 mW continuous discharge was performed on the battery immediately after production, and the discharge time was measured. Here, the final voltage was 1.0V. Next, the internal resistance of the battery immediately after fabrication was measured and evaluated. The results are shown in Table 1.

[0064]

[Table 1]

Tables 1 to 1 show that Examples 1 to 4 are effective in discharging 1500 mW. The internal resistance of the batteries of Examples 1 to 4 is 0.070 to 0.076 Ω, which is lower than the others. It is considered that this is because the zinc network can be secured because there is a locally dense zinc portion and a portion that holds the electrolytic solution.

The batteries of Examples 1 to 4 were 1500 mW.
The discharge time in heavy load discharge of 20 to 22 minutes is superior to other batteries. It is considered that this is because the volume of the gelling agent in the gelled negative electrode is controlled, so that the contact area between the granular zinc and the electrolytic solution can be secured without hindering the network between zincs.

Looking at Comparative Examples 1 and 2, the internal resistance was 0.0
85 to 0.092Ω, which is a large value as compared with Examples 1 to 4. It is considered that this is because the volume ratio of the gelling agent after swelling is within the optimum range, but the average particle size is as small as 1.1 mm, which makes it difficult to secure the zinc network.

Further, in Comparative Examples 1 and 2, the discharge time is shorter by 11 to 13 minutes as compared with Examples 1 to 4. This is because the average particle size is as small as 1.1 mm, which makes it difficult to secure a zinc network and raises the internal resistance. Also, when the internal resistance is high, the characteristics of heavy load discharge deteriorate. it is conceivable that.

Next, looking at Comparative Examples 3 and 4, the internal resistance is 0.075 to 0.080 Ω, which is a slightly larger value than those of Examples 1 to 4.

Further, in Comparative Example 3.4, the discharge time was as short as 12 to 16 minutes as compared with Examples 1 to 4. It is considered that this is because the zinc powder had been separated from the electrolytic solution, and the reaction could not be performed according to the request of the external load.

Next, looking at Comparative Examples 5 and 6, the internal resistance is 0.075 to 0.078 Ω, which is about the same value as in Examples 1 to 4. It is considered that this is because the volume ratio of the gelling agent after swelling is as small as 3%, so that the granular zinc and the electrolytic solution are separated from each other and the contact between the granular zinc particles can be secured.

However, in Comparative Examples 5 and 6, the discharge time is as short as 13 to 15 minutes as compared with Examples 1 to 4. It is considered that this is because the contact area between the granular zinc and the electrolytic solution is small due to the small volume ratio of the gelling agent in the gelled negative electrode, so that the electrolytic solution is not supplied in response to the demand for external load.

Next, looking at Comparative Examples 7 and 8, the internal resistance is 0.097 to 0.100 Ω, which is a large value as compared with Examples 1 to 4. This is considered to be because the average particle size of the gelling agent after swelling is within the optimum range but the volume ratio is as large as 15%, which hinders the formation of a network of granular zinc.

Further, in Comparative Examples 7 and 8, the discharge time was shorter by 11 to 16 minutes than in Examples 1 to 4. It is considered that this is because the gelling agent has a large volume ratio, so that the gelling agent absorbs a large amount of the electrolytic solution, which hinders the supply of the electrolytic solution during the discharge reaction.

Further, in the conventional example, as compared with Examples 1 to 4,
Since the average particle diameter is small and the volume ratio is small, the internal resistance is as large as 0.085Ω and the discharge time is as short as 13 minutes.

The batteries of the above-mentioned conventional example, Examples 1 to 4 and Comparative Examples 1 to 8 did not have a problem regarding the leakage resistance.

From the above, according to this example, the average particle diameter (D) of the gelling agent after swelling was 1.6 mm ≦ D ≦ 1.
Improving the discharge characteristics in the heavy load region by using a gelled negative electrode having a volume ratio (R) of the gelling agent in the negative electrode of 5.5% ≦ R ≦ 12.0% in the range of 9 mm. You can Further, the mass ratio (GE) of gelling agent / electrolyte before swelling is preferably in the range of 2.5 ≦ GE ≦ 4.0.

[0078]

The present invention has the following effects. The average particle size (D) of the gelling agent after swelling is 1.6
By setting the volume ratio (R) of the gelling agent after swelling in the range of mm ≦ D ≦ 1.9 mm and the range of 5.5% ≦ R ≦ 12.0%, the discharge characteristics in the heavy load region can be improved. Can be improved.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of the invention relating to a negative electrode and an alkaline battery.

[Explanation of symbols]

1 ... Battery, 2 ... Battery can, 3 ... Positive electrode, 4 ... Separator, 5 ... Negative electrode, 6 ... Sealing member, 7 ... Washer, 8 ... Negative electrode terminal plate, 9 ... Current collecting pin

Continued front page    F term (reference) 5H024 AA03 AA14 BB07 BB08 CC02                       DD14 DD17 EE09 FF10 GG01                       HH01 HH13                 5H050 AA02 BA03 BA04 CA05 CB13                       DA03 DA14 EA23 FA17 GA10                       GA23 HA01 HA05 HA07

Claims (10)

[Claims] 1. A negative electrode for use in an alkaline battery, comprising a granular zinc, an alkaline aqueous solution, and a gelling agent, wherein the gelling agent has an average particle size (D) after swelling of 1.6 mm. ≦ D ≦ 1.9 mm, and the gelling agent has a volume ratio (R) after swelling of 5.5%.
A negative electrode for a battery, which is in the range of ≦ R ≦ 12.0%. 2. The negative electrode for a battery according to claim 1, wherein the mass ratio (GE) of the gelling agent before swelling to the alkaline aqueous solution is in the range of 2.5 ≦ GE ≦ 4.0. 3. The negative electrode for a battery according to claim 2, wherein the gelling agent is made of a super absorbent polymer. 4. The negative electrode for a battery according to claim 3, wherein the superabsorbent polymer comprises crosslinked polyacrylic acid or crosslinked polyacrylic acid salt. 5. The negative electrode for a battery according to claim 4, wherein the cross-linked polyacrylic acid salt is a sodium salt. 6. A positive electrode, a negative electrode, and a separator are provided,
In an alkaline battery in which the negative electrode contains granular zinc, an alkaline aqueous solution, and a gelling agent, the gelling agent has an average particle diameter (D) after swelling in a range of 1.6 mm ≦ D ≦ 1.9 mm. And the gelling agent has a volume ratio (R) after swelling in a range of 5.5% ≦ R ≦ 12.0%. 7. The alkaline battery according to claim 6, wherein the mass ratio (GE) of the gelling agent before swelling to the alkaline aqueous solution is in the range of 2.5 ≦ GE ≦ 4.0. 8. The alkaline battery according to claim 7, wherein the gelling agent comprises a super absorbent polymer. 9. The alkaline battery according to claim 8, wherein the superabsorbent polymer comprises crosslinked polyacrylic acid or crosslinked polyacrylic acid salt. 10. The alkaline battery according to claim 9, wherein the cross-linked polyacrylic acid salt is a sodium salt.