JP2008117673A - Alkaline battery and manufacturing method of alkaline battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a positive electrode binder capable of improving a heavy load discharge performance by having a sufficient core strength at the positive electrode active material and preventing contact failure between the positive electrode active materials at the time of pressing into the positive electrode can. <P>SOLUTION: The alkaline battery has a potassium hydroxide electrolytic solution and a negative electrode agent (5) filled in a positive electrode can (1) of hollow pillar-shape in which a positive electrode mixture (3) having a positive electrode active material of either one of manganese dioxide and nickel oxy-hydroxide, a positive electrode binder, and potassium hydroxide is pressed. The positive electrode binder is used which has 15,000 mPa s or more of high concentration viscosity in which the positive electrode binder is contained 2.0 wt.% in a potassium hydroxide solution of 40 wt.% and 500 mPa s or less of low concentration viscosity in which the positive electrode binder is contained 1.0 wt.% in the potassium hydroxide solution of 40 wt.%. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an alkaline battery including a positive electrode mixture having a positive electrode active material of at least one of manganese dioxide and nickel oxyhydroxide, and a method for producing the alkaline battery.

  In general, as shown in FIG. 6, the alkaline battery is formed such that a conductive film 2 made of graphite is applied to the inner peripheral wall surface of a bottomed cylindrical positive electrode can 1, and the outer peripheral surface is in contact with the conductive film 2. A cylindrical positive electrode mixture 3 impregnated with a potassium hydroxide electrolyte is disposed in the positive electrode mixture 3. The separator 4 is filled with the negative electrode agent 5, and the current collector rod 6 is inserted into the negative electrode agent 5, so that the upper end opening of the positive electrode can 1 is covered with the gasket 10 via the gasket 10. A disc-shaped negative electrode terminal plate 11 is provided.

  The positive electrode mixture 3 is prepared by adding graphite, a positive electrode binder, and an aqueous potassium hydroxide solution to at least one of positive electrode active materials of manganese dioxide and nickel hydroxide, wet-mixing them, and pulverizing them into granules, followed by press molding. By doing so, it is formed in a cylindrical shape. As this positive electrode binder, the thing with a low thickening effect, such as polyethylene, is used (for example, patent document 1).

  However, an alkaline battery in which a large amount of a low-viscosity effect such as polyethylene is mixed as the positive electrode binder has a drawback in that the amount of the positive electrode active material that directly contributes to the battery reaction is reduced (for example, Patent Document 1). Therefore, if it is attempted to reduce the filling amount of the positive electrode binder, sufficient core strength cannot be obtained in the positive electrode mixture 3, and as a result, when the positive electrode can 1 is press-fitted into the positive electrode can 1, breakage or the like is broken. As a result, there is a fear that the destroyed portion may not contribute to the electrode reaction.

  On the other hand, in the alkaline battery using the above-mentioned positive electrode binder having a high thickening effect, the positive electrode binder absorbs the potassium hydroxide electrolyte and expands, so that the positive electrode active materials in the positive electrode mixture 3 and the positive electrode active materials are expanded. There was a problem that the contact between the substance and the can deteriorated, the internal resistance increased, and the heavy load discharge performance deteriorated.

JP 2003-017042 A

  The present invention was made in view of such circumstances, has sufficient core strength when press-fitting, and prevents contact between the positive electrode active materials and the positive electrode active material and the can during use, It aims at providing the manufacturing method of the alkaline battery provided with the positive electrode mixture which is excellent in heavy load capacity electrical performance, and an alkaline battery.

  In order to solve the above-mentioned problems, in the invention described in claim 1, a positive electrode mixture containing at least one positive electrode active material of manganese dioxide and nickel oxyhydroxide, a positive electrode binder, and potassium hydroxide is press-fitted. A bottomed cylindrical positive electrode can is filled with a potassium hydroxide electrolyte and a negative electrode agent, and an alkaline battery in which a negative electrode terminal plate is installed in the opening of the positive electrode can, wherein the positive electrode binder comprises: When the positive electrode binder is contained in an amount of 2.0% by mass in a 40% by mass potassium hydroxide solution, the high concentration viscosity is 15000 mPa · s or more, and the positive electrode binder in the 40% by mass potassium hydroxide solution. Is characterized by having a low concentration viscosity of 500 mPa · s or less.

  The invention described in claim 2 is the alkaline battery according to claim 1, wherein the ratio of the high concentration viscosity / the low concentration viscosity of the positive electrode binder is 50 or more.

  Furthermore, the invention according to claim 3 is the alkaline battery according to claim 1 or 2, wherein the positive electrode binder is a carboxyvinyl polymer, and the mass thereof is the moisture mass in the positive electrode mixture of the assembled battery. It is characterized by being 1/100 or less.

  On the other hand, in the invention according to claim 4, after mixing a positive electrode active material of at least one of manganese dioxide and nickel oxyhydroxide and a positive electrode binder made of carboxyvinyl polymer, a potassium hydroxide solution is added and wet mixed. The wet mixture is pulverized into granules and press-molded into a predetermined shape, and the positive electrode mixture is press-fitted into a bottomed cylindrical positive can. An alkaline battery manufacturing method comprising an assembly step of filling a potassium hydroxide electrolyte and a negative electrode agent and installing a negative electrode terminal plate in the opening of the positive electrode can, obtained by the positive electrode mixture forming step. The positive electrode binder of the alkaline battery obtained by the assembly process is set so that the mass of the positive electrode binder in the positive electrode mixture is 1.5% or more of the moisture mass in the positive electrode mixture. The mass of the positive electrode binder in a fixed combination, is characterized in that not more than 1.0% moisture by weight in the positive electrode mixture.

  According to the alkaline battery according to any one of claims 1 to 3, the high-concentration viscosity when 2.0% by mass of the positive electrode binder is contained in a 40% by mass potassium hydroxide solution as the positive electrode binder is 15000 mPas. Since it was s or more and a low-concentration viscosity when 1.0% by mass of the positive electrode binder was contained in a 40% by mass potassium hydroxide solution was 500 mPa · s or less, the positive electrode mixture Is pressed into the positive electrode can, the concentration of the positive electrode binder is high, the core strength required for the positive electrode mixture can be imparted, and in use, the electrolyte impregnated in the separator, etc. By reducing the viscosity of the positive electrode binder due to a decrease in the concentration of the positive electrode binder due to, the expansion of the positive electrode mixture due to the penetration of the potassium hydroxide electrolyte can be prevented.

  As a result, when the positive electrode mixture is pressed into the positive electrode can, the positive electrode mixture can be prevented from being broken or broken, and when using an alkaline battery, the contact deterioration between the positive electrode active materials can be prevented. Therefore, it is possible to prevent the heavy load discharge performance from being hindered due to the increase in internal resistance in the positive electrode can.

  In particular, according to the invention described in claim 2, by using a positive electrode binder in which the ratio of high concentration viscosity / low concentration viscosity in 40% by mass of calcium hydroxide is 50 or more, the positive electrode mixture is mixed with time. Prevents the expansion of the positive electrode mixture due to the absorption of the potassium hydroxide electrolyte, and prevents the increase in internal resistance in the positive electrode can after storage in an alkaline battery.

  As such a positive electrode binder, a carboxyvinyl polymer such as polyacrylic acid or sodium polyacrylate can be suitably used as in the invention described in claim 3. In addition, by adding this carboxyvinyl polymer so that the mass thereof becomes 1/100 or less of the moisture mass of water such as the positive electrode active material in the positive electrode mixture or the solvent of the potassium hydroxide solution, an alkaline battery is obtained. An increase in internal resistance after storage can be prevented.

  Furthermore, according to the method for producing an alkaline battery according to claim 4, the mass of the positive electrode binder made of the carboxyvinyl polymer in the positive electrode mixture obtained by the forming step of the positive electrode mixture is determined based on the moisture in the positive electrode mixture. By setting the mass to 1.5% or more, the thickening effect required for the positive electrode mixture can be imparted during press-fitting into the positive electrode can. In addition, by setting the mass of the positive electrode binder in the positive electrode mixture of the alkaline battery obtained by the assembly process to 1.0% or less of the moisture mass in the positive electrode mixture, the positive electrode active when using the alkaline battery is reduced. Prevents deterioration of contact between substances and cathode active material and can, prevents heavy load discharge performance from being hindered by increased internal resistance, and expands due to absorption of potassium hydroxide electrolyte in cathode mixture over time It is possible to prevent the increase in internal resistance in the positive electrode can after being stored in an alkaline battery.

An embodiment of an alkaline battery according to the present invention will be described.
In the alkaline battery of the present embodiment, the positive electrode mixture 3 contains a positive electrode active material made of manganese dioxide, graphite, a positive electrode binder, and a 40% by mass potassium hydroxide aqueous solution. The positive electrode mixture 3 is pressed into the axial direction of the positive electrode can 1 along the axial direction, and a plurality (three in the present embodiment) are loaded along the axial direction of the positive electrode can 1. .

  The positive electrode binder has a high concentration viscosity of 15000 mPa · s or higher when 40% by mass of the positive electrode binder is contained in 40% by mass of potassium hydroxide aqueous solution, and 40% by mass of potassium hydroxide. A solution having a low concentration viscosity of 5000 mPa · s or less when 1.0% by mass of the positive electrode binder is contained in the aqueous solution is used, and preferably the ratio of the high concentration viscosity / the low concentration viscosity is 50 or more. Things are used. As such a positive electrode binder, a carboxyvinyl polymer such as polyacrylic acid or sodium polyacrylate is used.

  Further, in the alkaline battery, a bottomed cylindrical separator 4 is accommodated in the positive electrode mixture 3, and the separator 4 is impregnated with an aqueous potassium hydroxide solution together with the positive electrode mixture 3. A gel-like negative electrode agent 5 in which zinc powder is mixed with a strong alkaline solution is injected into the separator 4 to a predetermined height, and a brass current collector 6 is inserted into the negative electrode agent 5 at a predetermined depth. It has been inserted.

  Furthermore, a substantially disc-shaped negative electrode terminal plate 11 is provided at the upper end opening of the positive electrode can 1 via an insulating gasket 10 to close the opening. A hole 10a for inserting the current collecting rod 6 is formed at the center of the gasket 10, and a thick cylindrical sealing portion 10b surrounding the current collecting rod 6 with a predetermined length is integrally formed. Is formed. And since this sealing part 10b closely_contact | adheres to the outer peripheral surface of the current collector rod 6, it is prevented that the electrolyte solution in the positive electrode can 1 leaks from the negative electrode side along the outer peripheral surface of the current collector rod 6, and this current collector. The top 6 a of the electric rod 6 is connected to the negative terminal plate 11 by welding.

  In the alkaline battery assembled as described above, insulation between the positive electrode can 1 and the negative electrode terminal plate 11 is ensured by the gasket 10, and the mass of the carboxyvinyl polymer as the positive electrode binder is manganese crystallization water or It is prepared so that it may become 1.0% or less of moisture mass, such as water in potassium hydroxide aqueous solution.

Next, a method for producing the alkaline battery according to the present invention will be described.
The alkaline battery manufacturing method of the present embodiment includes a positive electrode mixture forming process for forming the above-described cylindrical positive electrode mixture, and an assembly process for manufacturing the alkaline battery by press-fitting the positive electrode mixture into the positive electrode can. Have

  First, in the step of forming the positive electrode mixture, graphite powder, a carboxyvinyl polymer as a positive electrode binder, and a 40% by mass potassium hydroxide aqueous solution are added to manganese dioxide powder as a positive electrode active material and wet mixed. This wet mixed powder (wet mixture) is rolled with a roller compactor to form a sheet. Next, after this sheet-like wet mixed powder is pulverized into granules, the granules are placed in a mold having a cylindrical cavity and press-molded, whereby a cylindrical positive electrode mixture 3 is obtained. Form.

  At this time, the mass of the carboxyvinyl polymer is adjusted to be 1.5% or more of the water mass such as 60% by mass of water contained in the crystal water of manganese dioxide or the aqueous potassium hydroxide solution.

  Next, in the assembly process, a plurality (three in the present embodiment) of the positive electrode mixture 3 is directed so that the axial direction of the positive electrode mixture 3 is directed to the axial direction of the bottomed cylindrical positive electrode can 1. The positive electrode mixture 3 is press-fitted so that the outer peripheral surface of the positive electrode mixture 3 is in contact with the conductive film 2 formed on the inner peripheral wall surface of the positive electrode can 1.

  Next, after the bottomed cylindrical separator 4 is accommodated in the positive electrode mixture 3, a 40 mass% potassium hydroxide electrolyte is injected into the positive electrode can 1, and then the zinc powder is strong in the positive electrode mixture 3. A gelled negative electrode agent 5 mixed with an alkaline solution is poured to a predetermined height. Then, a brass current collector rod 6 is inserted into the negative electrode agent 5, and a gasket 10 and a negative electrode terminal plate 11 welded to the top 6 a of the current collector rod 6 are disposed in the upper end opening of the positive electrode can 1. An alkaline battery was assembled.

  The alkaline battery thus obtained is prepared such that the mass of the carboxyvinyl polymer is 1.0% or less of the moisture mass by filling with the potassium hydroxide electrolyte solution or the like in the positive electrode can 1. Increase in internal resistance is suppressed.

  Next, various experiments were conducted on changes in the core strength of the positive electrode mixture and the internal resistance of the alkaline battery due to changes in the viscosity of the positive electrode binder.

[Experimental Example 1] Relationship between High Concentration Viscosity and Core Strength While preparing polyacrylic acid as 1-1 to 1-3, sample no. Polyethylene was prepared as 1-4, and polyacrylic acid was prepared as samples 1-5 to 1-7.

  Next, the viscosity (high concentration viscosity) of the sample obtained by adding the positive electrode binder of each of the samples 1-1 to 1-7 to 2.0% by mass in a 40% by mass potassium hydroxide aqueous solution was determined by Brookfield. (Trade name) Rotational viscometer DV-1 + (manufactured by Brookfield) Measured using LV-5 and shown in Table 1.

  Next, 90 parts by mass of EMD powder and 7 parts by mass of graphite powder were mixed with 10 parts by mass of each of the above-mentioned samples, and 3 parts by mass of 40% by mass of potassium hydroxide were added to these powder mixtures. The aqueous solution was added and wet mixed.

Next, the wet mixed powder was rolled with a roller compactor to form a sheet, and then the wet mixed powder in the form of a sheet was pulverized into a granular form, and a cylindrical cavity was formed in the granular powder. A positive electrode mixture was prepared by press molding in a mold. As a result, the core dimensions of the obtained cylindrical positive electrode mixture are as follows: the outer shape is 13.4 mm, the inner diameter is 9.0 mm, the axial height is 13.5 mm, the weight is 3.45 g, and the molding density is 3.30 g. / Cm ³ .

  Next, each positive electrode mixture is placed on a horizontal test stand with the axial direction being horizontal, and a gradually increasing pressure is applied from the top to the bottom of each positive electrode mixture. The strength was measured and shown in Table 1, and the core strength with respect to the high concentration viscosity of the positive electrode binder of each positive electrode mixture was shown as a line graph in FIG.

  As can be seen from Table 1 and FIG. 1, a positive electrode binder having a high concentration viscosity of 15000 mpa · s or more when 2% by mass of the positive electrode binder is contained in a 40% by mass potassium hydroxide aqueous solution is used. When the positive electrode mixture is prepared, the core strength is remarkably increased. Therefore, when this positive electrode mixture is pressed into the positive electrode can, breakage such as cracking of the positive electrode mixture can be efficiently prevented.

[Experimental Example 2] Relationship between low concentration viscosity and initial internal resistance value As 2-1 to 2-6, polyacrylic acid was prepared. The viscosity of each sample was measured and shown in Table 2 in the same manner as in Experimental Example 1 except that LV-5 was replaced with LV-2.

Then, each sample No. Using 2-1 to 2-6, three positive electrode mixtures were prepared in the same manner as in Experimental Example 1, and the three positive electrode mixtures prepared from the same samples were respectively pressed into the same positive electrode cans. And after accommodating a separator in these positive electrode mixtures, 40 mass% potassium hydroxide electrolyte solution was inject | poured. Next, the gelled negative electrode agent 5 in which 65% by mass of zinc powder is mixed with a strong alkaline solution (40% by mass KOH / 3.0% ZnO) is filled, and the current collector rod 6 is inserted, whereby an alkaline battery is obtained. Assembled.

  The initial internal resistance value of each AA alkaline battery (LR6) thus obtained was measured and shown in Table 2, and the initial internal resistance value of the alkaline battery with respect to the low concentration viscosity of the positive electrode binder of each alkaline battery was determined. A line graph is shown in FIG.

  As can be seen from Table 2 and FIG. 2, as the positive electrode binder, an alkali using a low concentration viscosity of 5000 mpa · s or less when 1% by mass of the positive electrode binder is contained in a 40% by mass potassium hydroxide aqueous solution. The battery has an initial internal resistance value of 90 or less. In contrast, an alkaline battery in which the low-concentration viscosity of the positive electrode binder exceeds 5000 mpa · s significantly increases the initial internal resistance value. Therefore, by manufacturing an alkaline battery using a positive electrode binder having a low-concentration viscosity of 5000 mpa · s or less, it is possible to prevent heavy load discharge performance from being hindered due to an increase in internal resistance in the positive electrode can.

[Experimental Example 3] Relationship between viscosity ratio and internal resistance after storage in alkaline battery Sample No. 2 having a high concentration viscosity of 2000 mpa · s. Polyacrylic acid was prepared as 3-1 to 3-3 and 3-11, and the low concentration viscosity of each sample was measured in the same manner as in Experimental Example 2 and shown in Table 3. In addition, polyacrylic acid was prepared as Samples 3-4, 3-5, and 3-12 having a low-concentration viscosity of 450 mpa · s, and the high-concentration viscosity of each sample was measured in the same manner as in Experimental Example 1. It was shown in 3. Further, the ratio of high concentration viscosity / low concentration viscosity of each sample was calculated and shown in Table 3.

  Then, using the positive electrode mixture prepared in the same manner as in Experimental Example 1 with each sample, an alkaline battery was manufactured in the same manner as in Experimental Example 2, and the internal resistance (AC method 1 kHz) after storage at 60 degrees for 20 days was measured. The results are shown in Table 3. When the positive electrode binder having a high concentration viscosity of 2000 mpa · s and the positive electrode binder having a low concentration viscosity of 450 mpa · s and the internal resistance of the alkaline battery with respect to the high concentration viscosity / low concentration viscosity ratio are used. FIG. 3 is a line graph showing the internal resistance of the alkaline battery with respect to the ratio of high concentration viscosity / low concentration viscosity.

  As can be seen from Table 3 and FIG. 3, even when using a positive electrode binder with a high concentration viscosity of 2000 mpa · s or a positive electrode binder with a low concentration viscosity of 450 mpa · s, the high concentration viscosity / low concentration viscosity When the ratio is 50 or more, the internal resistance after the storage is remarkably lowered, and an increase in the internal resistance in the positive electrode can with time can be prevented.

[Experimental Example 4] Relationship between the positive electrode binder mass / moisture mass ratio of the positive electrode mixture and the core strength Polyacrylic acid was prepared as 4-1 to 4-6, and a positive electrode mixture was prepared using each sample in the same manner as in Experimental Example 1. At that time, the ratios of various powders and aqueous potassium hydroxide solution were prepared so that the ratio of the positive electrode binder mass / water mass of each sample was the ratio shown in Table 4.
Next, the core strength of each of these samples was measured by the same method as in Experimental Example 1 and shown in Table 4, and the core strength with respect to the positive electrode binder mass / water mass ratio was shown as a line graph in FIG. .

  As can be seen from Table 4 and FIG. 4, when the positive electrode binder mass / water mass is 1.5% or more, the core strength is stable at 6.5 N or more, whereas it is less than 1.5%. The core strength is significantly reduced. Therefore, by setting the mass / moisture content of the positive electrode binder to 1.5% or more, it is possible to efficiently prevent cracking of the positive electrode mixture when it is press-fitted into the positive electrode can.

[Experimental Example 5] Relationship between the ratio of the positive electrode binder mass / water mass of the alkaline battery and the internal resistance after storage of the alkaline battery Polyacrylic acid was prepared as 5-1 to 5-6, and AA alkaline batteries were prepared using each sample in the same manner as in Experimental Example 2. At that time, the proportions of various powders, potassium hydroxide aqueous solution, and the like were prepared such that the ratio of the positive electrode binder mass / water mass of the alkaline battery was in the range of 0.5 to 2.0 as shown in Table 5.

  Next, the internal resistance of each of these samples was measured by the same method as in Experimental Example 3 and shown in Table 5, and the internal resistance with respect to the positive electrode binder mass / water mass ratio was shown as a line graph in FIG.

  As can be seen from Table 5 and FIG. 5, when the ratio of the positive electrode binder mass / water mass is 1.0% or less, the alkaline battery has a stable internal resistance of 110 mΩ or less after storage at 60 degrees for 20 days. On the other hand, when the mass ratio exceeds 1.0%, the internal resistance after the storage is remarkably increased.

  According to the alkaline battery of the present embodiment, since the positive electrode binder having a high concentration viscosity of 15000 mPa · s or more and a low concentration viscosity of 500 mPa · s or less is used, the positive electrode mixture at the time of press-fitting into the positive electrode can The positive electrode due to expansion of the positive electrode mixture can be efficiently prevented by preventing the potassium hydroxide electrolyte from penetrating into the positive electrode mixture when assembling the alkaline battery. It is possible to prevent contact deterioration between the active materials and between the positive electrode active material and the can. As a result, it is possible to improve the handling properties such as the conveyance and press-fitting of the positive electrode mixture, and it is possible to prevent the heavy load discharge performance from being hindered due to the increase in the internal resistance in the positive electrode can.

  In particular, by using a positive electrode binder having a high concentration viscosity / low concentration viscosity ratio of 50 or more, it is possible to prevent expansion due to absorption of the potassium hydroxide electrolyte of the positive electrode mixture over time, and storage in an alkaline battery. The increase in internal resistance in the positive electrode can later can be prevented. In addition, since a carboxyvinyl polymer was used as the positive electrode binder, the mass of the carboxyvinyl polymer was adjusted to 1/100 or less of the water mass due to crystallization water or potassium hydroxide aqueous solution of the positive electrode active material in the positive electrode mixture. Further, it is possible to effectively prevent the increase in internal resistance after storage of the alkaline battery.

  Furthermore, according to the method for producing an alkaline battery of the present embodiment, the mass of the positive electrode binder composed of the carboxyvinyl polymer in the positive electrode mixture obtained by the step of forming the positive electrode mixture is set to the moisture mass in the positive electrode mixture. By making the mass of the positive electrode binder in the positive electrode mixture of the alkaline battery obtained by the assembly process to be 1.5% or more and 1.0% or less of the moisture mass in the positive electrode mixture, the positive electrode can A thickening effect required in press-fitting into the inside can be imparted to the positive electrode mixture, and an increase in internal resistance during use and after storage can be prevented. As a result, it is possible to improve the handling properties such as the conveyance and press-fitting of the positive electrode mixture, and it is possible to prevent the heavy load discharge performance from being hindered due to the increase in the internal resistance in the positive electrode can.

  In addition, this invention is not limited to the above-mentioned embodiment at all, For example, you may use nickel oxyhydroxide as a positive electrode active material.

It is the line graph which showed the core intensity | strength (N) with respect to the positive electrode binder high concentration viscosity (mpa * s) of each positive electrode mixture. It is the line graph which showed the initial stage internal resistance value (m (ohm)) of the alkaline battery with respect to the low concentration viscosity (mpa * s) of the positive electrode binder of each alkaline battery. Internal resistance (mΩ) after storage of an alkaline battery with respect to the ratio of high concentration viscosity / low concentration viscosity when using a positive electrode binder having a high concentration viscosity of 20000 mpa · s, and a positive electrode binder having a low concentration viscosity of 450 mpa · s 6 is a line graph showing the internal resistance (mΩ) after storage of the alkaline battery with respect to the ratio of the high concentration viscosity / low concentration viscosity when using. It is the line graph which showed the core intensity | strength (N) with respect to the positive electrode binder mass / moisture mass x100 (%) of a positive mix. It is the line graph which showed the internal resistance (mohm) after the preservation | save with respect to the positive electrode binder mass / moisture mass x100 (%) of an alkaline battery. It is a longitudinal cross-sectional view of the principal part which shows one Embodiment of the alkaline battery which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Positive electrode can 2 Conductive film 3 Positive electrode mixture 4 Separator 5 Negative electrode agent 6 Current collecting rod 11 Negative electrode terminal board

Claims (4)

A positive electrode mixture containing at least one positive electrode active material of manganese dioxide and nickel oxyhydroxide, a positive electrode binder, and potassium hydroxide is pressed into a bottomed cylindrical positive electrode can, and a potassium hydroxide electrolyte solution Is an alkaline battery in which a separator and a negative electrode agent impregnated are accommodated, and a negative electrode terminal plate is installed in the opening of the positive electrode can,
The positive electrode binder has a high concentration viscosity of 15000 mPa · s or more and a 40% by mass potassium hydroxide solution when 2.0% by mass of the positive electrode binder is contained in a 40% by mass potassium hydroxide solution. An alkaline battery having a low concentration viscosity of 500 mPa · s or less when 1.0% by mass of the positive electrode binder is contained therein.   The alkaline battery according to claim 1, wherein the positive electrode binder has a ratio of the high concentration viscosity / the low concentration viscosity of 50 or more.   3. The alkaline battery according to claim 1, wherein the positive electrode binder is a carboxyvinyl polymer, and the mass thereof is 1/100 or less of the moisture mass in the positive electrode mixture of the assembled battery. After mixing the positive electrode active material of at least one of manganese dioxide and nickel oxyhydroxide and the positive electrode binder made of carboxyvinyl polymer, a potassium hydroxide solution is added and wet mixed, and the wet mixture is pulverized into granules. After forming the positive electrode mixture into a predetermined shape and press-fitting the positive electrode mixture into the bottomed cylindrical positive electrode can, the positive electrode can is filled with a potassium hydroxide electrolyte and a negative electrode agent. And an assembly process of installing a negative electrode terminal plate in the opening of the positive electrode can,
The mass of the positive electrode binder in the positive electrode mixture obtained by the formation step of the positive electrode mixture is 1.5% or more of the moisture mass in the positive electrode mixture, and the alkaline battery obtained by the assembly step The method for producing an alkaline battery, wherein a mass of the positive electrode binder in the positive electrode mixture is 1.0% or less of a moisture mass in the positive electrode mixture.

Images