JP2008010250A - Alkali battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an alkali battery with excellent leakage resistance and discharge performance in which gas generation of a negative electrode is suppressed even when a negative electrode with excellent reactivity is used. <P>SOLUTION: The alkali battery includes the negative electrode containing a negative electrode active material and anionic surface active agent. The surface active agent is a compound having a structure expressed by a general formula (1) or its alkali metal salt. The negative electrode active material is zinc alloy powder of a gas evolution rate 5-30 μl/g day in a solution at 45 °C containing 38 wt.% of potassium hydroxide and 2 wt.% of zinc oxide. In the formula, R<SB>1</SB>and R<SB>2</SB>are respectively independent, and are a hydrogen atom or 1-26C hydrocarbon radical, and a total of carbon numbers of R<SB>1</SB>and R<SB>2</SB>is 1-26. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an alkaline battery, and more particularly to a negative electrode of an alkaline battery.

Generally, an alkaline battery has a cylindrical positive electrode mixture containing manganese dioxide powder as a positive electrode active material in close contact with the battery case in a battery case also serving as a positive electrode terminal, and a negative electrode through a separator in the center. It has a structure in which a gelled negative electrode containing zinc alloy powder is disposed as an active material.
Conventionally, various studies have been made to improve the performance of negative electrodes in alkaline batteries. For example, Patent Document 1 proposes to pulverize zinc alloy powder to increase the reaction area in order to improve discharge performance. However, since the reactivity of the zinc alloy powder is improved, the corrosion tends to proceed and the corrosion resistance is lowered.

On the other hand, Patent Document 2 proposes to add a phosphate ester as an anionic surfactant having alkali resistance to the negative electrode in order to improve the corrosion resistance of the negative electrode.
The surfactant forms an aggregate and is adsorbed on the surface of the zinc particles to form a protective coating layer. This protective coating layer prevents the hydroxide ions and water from approaching the zinc particles, and the reactions of the formulas (1) and (2) on the surface of the zinc particles are suppressed.
^{Zn + 4OH - → Zn (OH} ) 4 2- + 2e - (1)
^{_{2H 2 O + 2e - → 2OH}} - + H 2 (2)

The surfactant as described above is dispersed from the surface of the zinc particles and diffuses into the electrolyte during the negative electrode reaction. However, when the number of carbon atoms increases, the adsorption force on the surface of the zinc particles increases, the diffusion rate decreases, and the progress of the electrode reaction shown in the formula (1) is likely to be hindered.
Moreover, in patent document 3, in order to improve the corrosion resistance of a negative electrode, the zinc alloy with few gas generation amounts is proposed. However, on the other hand, there is a problem that the reactivity of the zinc alloy is lowered and the discharge performance is lowered.
Thus, it has been difficult to achieve both improved discharge performance and improved corrosion resistance of the negative electrode.
Special table 2001-512284 gazette JP 55-69969 A JP-A-11-265715

  Therefore, in order to solve the above-described conventional problems, the present invention provides an alkaline battery having excellent discharge performance and leakage resistance, in which gas generation of the negative electrode is suppressed even when a negative electrode having excellent reactivity is used. The purpose is to do.

  In order to solve the conventional problems as described above, the inventors combined a highly reactive zinc alloy powder and a surfactant in order to achieve both improved discharge performance and improved corrosion resistance of the negative electrode. As a result of intensive studies on the correlation between the gas generation amount (reactivity) of the zinc alloy powder and the anticorrosive effect of the surfactant, the present invention has been completed.

  That is, the alkaline battery of the present invention includes a positive electrode including a positive electrode active material composed of at least one of manganese dioxide powder and nickel oxyhydroxide powder, a negative electrode including a negative electrode active material and an anionic surfactant, and the positive electrode and the negative electrode. A separator disposed between and an alkaline electrolyte, and the surfactant is represented by the general formula (1):

(Wherein R ₁ and R ₂ are each independently a hydrogen atom or a hydrocarbon group having 1 to 26 carbon atoms, and the total carbon number of R ₁ and R ₂ is _{1 to} 26). A compound having the structure represented or an alkali metal salt thereof,
The negative electrode active material is a zinc alloy powder having a gas generation rate of 5 to 30 μl / g · day in a 45 ° C. aqueous solution containing 38 wt% potassium hydroxide and 2 wt% zinc oxide. .

In the general formula (1), R ₁ and R ₂ are each independently a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms, and the total number of carbon atoms of R ₁ and R ₂ is 1 to 6. Preferably there is.
In the general formula (1), R ₁ is H— (CH ₂ ) _m —, R ₂ is H— (CH ₂ ) _n —, m = 0 to 26, n = 0 to 26, and m + n. = 1 to 26 is preferable.
In the general formula (1), R ₁ is H— (CH ₂ ) _m —, R ₂ is H— (CH ₂ ) _n —, m = 0 to 6, n = 0 to 6, and m + n. = 1 to 6 is preferable.

The negative electrode preferably contains the surfactant in an amount of 0.005 to 1 part by weight per 100 parts by weight of the zinc alloy powder.
The zinc alloy powder preferably contains 5 to 100 ppm of aluminum, 30 to 150 ppm of bismuth, and 0 to 250 ppm of indium.

  According to the present invention, even when a negative electrode having excellent reactivity is used, gas generation of the negative electrode can be suppressed, and thus both excellent discharge performance and leakage resistance can be achieved.

The present invention provides a positive electrode including a positive electrode active material comprising at least one of manganese dioxide powder and nickel oxyhydroxide powder as a positive electrode active material, a negative electrode including a negative electrode active material and an anionic surfactant, and the positive electrode and the negative electrode. The present invention relates to an alkaline battery including a separator disposed between them and an alkaline electrolyte.
The surfactant is represented by the general formula (1):

(Wherein R ₁ and R ₂ are each independently a hydrogen atom or a hydrocarbon group having 1 to 26 carbon atoms, and the total carbon number of R ₁ and R ₂ is _{1 to} 26). In a 45 ° C. aqueous solution (hereinafter referred to as a test solution) containing 38% by weight of potassium hydroxide and 2% by weight of zinc oxide as the negative electrode active material, which is a compound having the structure represented or an alkali metal salt thereof It is characterized in that a zinc alloy powder having a gas generation rate of 5 to 30 μl / g · day is used.

The present inventors have selected a surfactant that exhibits excellent anticorrosion properties even for highly reactive (a large amount of gas generation) zinc alloy powder, and a zinc alloy in which this surfactant is used. The relationship between the amount of gas generated in the powder (high reactivity) and the corrosion resistance of the negative electrode was examined.
As a result, it was found that in the above case, an alkaline battery capable of achieving both improved discharge performance and improved corrosion resistance of the negative electrode was obtained.

When the gas generation rate of the zinc alloy powder in the test solution is in the range of 5 to 30 μl / g · day, by using the above surfactant, the gas generation rate as the negative electrode is set at a level at which the battery does not leak (for example, 10 μl / g · day or less).
If the gas generation rate of the zinc alloy powder in the test solution exceeds 30 μl / g · day, the corrosion resistance of the negative electrode cannot be sufficiently obtained even if the above surfactant is used. When the gas generation rate of the zinc alloy powder is less than 5 μl / g · day, the reactivity of the zinc alloy becomes low, and the discharge performance may be lowered.

Since the surfactant has an adsorption power to the surface of the zinc alloy particles such that the discharge performance does not deteriorate, the corrosion resistance of the negative electrode can be improved without impairing the discharge performance.
The phosphorus content in the compound of the general formula (1) is 12 to 28 atomic%.
When the carbon number of R ₁ or R ₂ or the sum of the carbon numbers of both exceeds 26, the adsorption power to the zinc alloy powder increases, so that the discharge performance decreases.

Furthermore, in order to improve the discharge performance, in the general formula (1), R ₁ and R ₂ are each independently a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms, and R ₁ and R ₂ The total number of carbon atoms is preferably 1-6. R ₁ and R ₂ may contain a double bond, and may be linear or branched.
For example, R ₁ is H— (CH ₂ ) _m — and R ₂ is H— (CH ₂ ) _n —, where m = 0 to 26, n = 0 to 26, and m + n = 1 to 26. Preferably, m = 0 to 6, n = 0 to 6, and m + n = 1 to 6.
Examples of the compound having the structure represented by the general formula (1) or the alkali metal salt thereof include, for example, the general formula (2):

(Wherein, m = 0 to 26, n = 0 to 26, and m + n = 1 to 26, and X and Y are each independently H, Na, or K). The compound which has is mentioned.
It is preferable that the negative electrode contains 0.005 to 1 part by weight of the surfactant per 100 parts by weight of the zinc alloy powder in that excellent liquid leakage resistance and discharge performance can be obtained at the same time. More preferably, the content of the surfactant in the negative electrode is 0.05 to 0.2 parts by weight per 100 parts by weight of the zinc alloy powder.

  For the negative electrode, for example, a gelled negative electrode made of a zinc alloy powder, a gelling agent, an alkaline electrolyte, and a mixture of the above additives is used. As the gelling agent, for example, sodium polyacrylate is used. For the alkaline electrolyte, for example, a potassium hydroxide aqueous solution or a sodium hydroxide aqueous solution is used.

  For the zinc alloy powder whose gas generation amount in the test solution is 5 to 30 μl / g · day, for example, a zinc alloy powder containing 5 to 100 ppm of aluminum, 30 to 150 ppm of bismuth, and 0 to 250 ppm of indium is used. It is done. In addition to the above, for example, a zinc alloy powder containing 100 to 200 ppm of calcium, 50 to 150 ppm of bismuth, and 200 to 300 ppm of indium is used.

  When the content of bismuth in the zinc alloy exceeds 150 ppm, the discharge performance is degraded. When the bismuth content in the zinc alloy is less than 30 ppm, the effect of improving the corrosion resistance of the negative electrode by bismuth cannot be sufficiently obtained. In order to reduce the amount of gas generated, it is preferable to add indium which has an effect of increasing the hydrogenation voltage. When the indium content in the zinc alloy exceeds 250 ppm, the effect of suppressing the amount of gas generated by indium remains the same. When the aluminum content in the zinc alloy exceeds 100 ppm, the discharge performance decreases. If the aluminum content in the zinc alloy is less than 5 ppm, the effect of improving the corrosion resistance by aluminum cannot be obtained sufficiently.

The gas generation rate in the test solution of zinc alloy powder can be measured, for example, as follows.
The bottomed cylindrical storage portion 11a, and the glass appliance 11 having an opening cylindrical portion 11b having a diameter smaller than that of the storage portion 11a connected to the opening portion of the storage portion 11a, and an insertion cylindrical shape corresponding to the opening cylindrical portion 11b A glass instrument 12 having a portion 12a, a tubular part 12b communicating with the lower part of the insertion cylindrical part 12a, and a cylindrical measuring part 12c with a scale communicating with the upper part of the insertion cylindrical part 12a; The insertion cylindrical part 12a of the glass instrument 12 is inserted into the open cylindrical part 11b so that the tubular part 12b is positioned in the storage part 11a, thereby constituting a test container. At this time, grease is applied between the insertion cylindrical portion 12a and the opening cylindrical portion 11b, thereby bringing the insertion cylindrical portion 12a and the opening tubular portion 11b into close contact with each other.

  Then, the zinc alloy powder 13 (weight: X (g)), 38 wt% potassium hydroxide, and 2 wt% of the sample are introduced from the opening of the measuring section 12 c of the glass apparatus 12 into the storage section 11 a of the glass apparatus 11. Test solution 14 containing zinc oxide and liquid paraffin 15 (manufactured by Kanto Chemical Co., Inc., deer grade 1) are added in this order. At this time, the amount of the test solution 14 is adjusted so that the test solution 14 is positioned below the tip of the tubular portion 12b.

  The gas generated in the storage part 11a stays in the upper part of the layer of liquid paraffin 15 in the storage part 11a, and the volume of paraffin 15 flows into the glass apparatus 12 through the tubular part 12b. The liquid paraffin 15 in the glass apparatus 12 is pushed upward, and the liquid level of the liquid paraffin 15 in the measurement unit 12c moves upward. In addition, it has the structure where the front-end | tip of the tubular part 12b was bent and the opening part was turned sideways so that the generated gas may not enter into the glass instrument 12. Therefore, the gas generation amount can be obtained from the amount of change in the liquid height of the liquid paraffin 15.

After leaving the test container in a 45 ° C. environment for 1 hour, the scale of the measurement unit 12c is read to measure the liquid height of the liquid paraffin 15. Further, after leaving the test container in a 45 ° C. environment for Y days, the liquid height of the liquid paraffin 15 is measured again by the same method. And the gas generation rate can be calculated | required using the following formula | equation.
Gas generation rate (μl / g · day) = (Liquid height after day Y (ml) −Liquid height after 1 hour (ml)) / (X (g) × Y (day)) × 1000

  As a method for adding the surfactant into the gelled negative electrode, the surfactant may be added to the gelled electrolyte which is a mixture of the alkaline electrolyte and the gelling agent when the gelled negative electrode is produced. The surfactant of the present invention is soluble in the gel electrolyte and is uniformly dispersed in the gel negative electrode. Moreover, you may make a separator and a positive electrode impregnate a surfactant at the time of battery preparation. After the battery is produced, the surfactant is dispersed in the electrolytic solution and adsorbed on the surface of the zinc alloy particles in the gelled negative electrode.

  In the gelled negative electrode, the zinc alloy powder is preferably contained in an amount of 170 to 220 parts by weight per 100 parts by weight of the electrolyte contained in the gel negative electrode. When the content of the zinc alloy powder in the gelled negative electrode is less than 170 parts by weight per 100 parts by weight of the electrolyte contained in the gelled negative electrode, the gelled negative electrode is liable to foam and discharge performance is deteriorated. On the other hand, when the content of the zinc alloy powder in the gelled negative electrode exceeds 220 parts by weight per 100 parts by weight of the electrolyte contained in the gel negative electrode, the amount of the electrolyte in the gel negative electrode is too small and the discharge performance is lowered. To do.

  In general, it is known that an aqueous solution to which a phosphate ester has been added increases the stability of foam. Therefore, when the negative electrode is produced, the gelled negative electrode is foamed to take in air, and the density of the gelled negative electrode is lowered. Therefore, the present inventors examined the relationship between the ratio of the amount of zinc alloy powder to the amount of electrolyte in the gelled negative electrode and the foamability of the gelled negative electrode. As a result, it was found that the lowering of the negative electrode density due to foaming was suppressed as the ratio of the amount of zinc alloy powder to the amount of electrolytic solution was larger. This is probably because the zinc alloy particles having a complicated shape have a greater effect of breaking bubbles.

In the negative electrode, the zinc alloy powder preferably contains 5 to 30% by weight of particles having a particle size of 75 μm or less. If the content of particles having a particle size of 75 μm or less in the zinc alloy powder is within the above range, the gas generation rate of the zinc alloy powder in the test solution is 5 to 30 μl / g · day. If the content of particles having a particle size of 75 μm or less in the zinc alloy powder exceeds 30% by weight, the gas generation rate of the zinc alloy powder in the test solution may exceed 30 μl / g · day.
Further, when the content of particles having a particle diameter of 75 μm or less in the zinc alloy powder is 5% by weight or more, the reaction efficiency of the negative electrode is improved and the discharge performance is improved. When the content of particles having a particle size of 75 μm or less in the zinc alloy powder exceeds 30% by weight, the productivity in the gelled negative electrode filling process is lowered.

Conventionally, when the zinc alloy powder is pulverized in order to increase the reaction efficiency of the negative electrode, there is a problem that the viscosity of the gelled negative electrode is increased and the productivity is deteriorated.
However, the viscosity of the gelled negative electrode is reduced by adding the surfactant. This is because the interfacial tension between the electrolyte, the zinc alloy particles and the gelling agent decreases, the wettability of the zinc alloy particles and the gelling agent increases, and the lubricity increases. It is considered that this is because the friction caused by the collision of can be reduced. Due to the decrease in the viscosity of the gelled negative electrode, the productivity of the step of filling the gelled negative electrode into the battery case is improved. In particular, phosphates with short carbon chains have a strong interfacial tension reducing ability.
Therefore, since the surfactant is added to the gelled negative electrode as described above, an increase in the viscosity of the gelled negative electrode can be suppressed even if a zinc alloy fine powder is used, and the discharge can be performed without reducing the productivity. Performance can be improved.

For the positive electrode, for example, a positive electrode mixture made of a mixture of a positive electrode active material, graphite powder as a conductive agent, and an alkaline electrolyte is used. As the positive electrode active material, manganese dioxide powder, nickel oxyhydroxide powder, or a mixture thereof is used.
For the separator, for example, a nonwoven fabric mainly composed of polyvinyl alcohol fiber and rayon fiber is used.

<< Examples 1-2 and Comparative Examples 1-4 >>
(1) Preparation of positive electrode mixture Manganese dioxide as a positive electrode active material, graphite as a conductive agent, and an electrolytic solution were mixed at a weight ratio of 100: 6: 1, and then compression molded into flakes. Subsequently, the flaky positive electrode mixture was pulverized into granules, which were classified by a sieve, and those having a 10 to 100 mesh shape were pressure-molded into a hollow cylinder to obtain a pellet-like positive electrode mixture. As the electrolytic solution, an aqueous solution containing 38% by weight of potassium hydroxide and 2% by weight of zinc oxide was used.

(2) Production of gelled negative electrode Zinc ingot was melted at about 500 ° C., and predetermined amounts of aluminum, bismuth, and indium were charged therein. A zinc alloy powder was obtained from a molten zinc alloy by an air atomization method. And this was classified with the sieve and the zinc alloy powder whose particle size is 25-425 micrometers and an average particle diameter of 165 micrometers was obtained. The obtained alloy was a zinc alloy containing 30 ppm of aluminum, 200 ppm of bismuth, and 500 ppm of indium.
On the other hand, a surfactant as an organic anticorrosive was added to the same electrolytic solution as above and stirred for 1 minute, and then sodium polyacrylate was added as a gelling agent and mixed for 45 minutes. Then, it was left to stand at room temperature for 10 minutes to obtain a gel electrolyte.

  To this gel electrolyte, the above zinc alloy powder was added and mixed for 30 minutes to obtain a gelled negative electrode. At this time, the mixing weight ratio of the electrolytic solution, the surfactant, the sodium polyacrylate, and the zinc alloy powder was 32.934: 0.066: 1: 66. As the surfactant, one in which m = 2, n = 0, and X and Y in the above general formula (2) are H was obtained by esterification reaction of phosphoric acid and ethyl alcohol. The addition amount of the surfactant in the gelled negative electrode was 0.2 parts by weight per 100 parts by weight of the zinc alloy powder.

(3) Assembly of alkaline battery The cylindrical AA alkaline battery shown in FIG. FIG. 1 is a front view with a cross section of a part of an alkaline battery.
Two pieces of the positive electrode mixture obtained above were inserted into the battery case 1, and the positive electrode mixture 2 was remolded with a pressure jig and brought into close contact with the inner wall of the battery case 1. And the bottomed cylindrical separator 4 was arrange | positioned in the center of the positive mix 2 arrange | positioned in the battery case 1, and predetermined amount injected the same electrolyte solution as the above into the separator 4. FIG. After a predetermined time had elapsed, the gelled negative electrode 3 obtained above was filled into the separator 4. In addition, the separator 4 used the nonwoven fabric which mixed and mixed mainly the polyvinyl alcohol fiber and the rayon fiber.

  Subsequently, the negative electrode current collector 6 was inserted into the center of the gelled negative electrode 3. Note that the negative electrode current collector 6 was previously integrated with a gasket 5 and a bottom plate 7 that also served as a negative electrode terminal. And the opening edge part in the battery case 1 was crimped to the peripheral part of the bottom plate 7 via the edge part of the gasket 5, and the opening part of the battery case 1 was sealed. Finally, the outer surface of the battery case 1 was covered with the exterior label 8 to obtain an alkaline battery.

At the time of producing the alkaline battery, the contents of Al, Bi, and In in the zinc alloy were changed as shown in Table 1, and batteries of Examples 1 and 2 and Comparative Example 1 were produced.
Further, batteries of Comparative Examples 2 to 4 were produced in the same manner as in Examples 1 and 2 and Comparative Example 1, respectively, except that the surfactant was not added during the production of the negative electrode.

[Evaluation]
(4) Measurement of gas generation rate of zinc alloy powder The gas generation rate of the zinc alloy powder was measured using the test container shown in Fig. 2 described above. After putting zinc alloy powder (weight: 10 (g)) into a test vessel, liquid paraffin (manufactured by Kanto Chemical Co., Ltd., deer) together with a test solution containing 38% by weight potassium hydroxide and 2% by weight zinc oxide. 1st grade) was put in a container. After the test container was allowed to stand for 1 hour in a 45 ° C. environment, the liquid height of the liquid paraffin was measured. Furthermore, after leaving the test container in a 45 ° C. environment for 3 days, the liquid height of the induced paraffin was measured again. And the gas generation amount was calculated | required using the following formula | equation.
Gas generation amount (μl / g · day) = (liquid height after 3 days (ml) −liquid height after 1 hour (ml)) / (10 (g) × 3 (day)) × 1000

(5) Measurement of gas generation rate of negative electrode Using the test container shown in FIG. 2 described above, the gas generation rate of the gelled negative electrode was measured. After the gelled negative electrode (weight: 10 (g)) was put into a test container, liquid paraffin was put into the container. After the test container was allowed to stand for 1 hour in a 45 ° C. environment, the liquid height of the liquid paraffin was measured. Furthermore, after leaving the test container in a 45 ° C. environment for 3 days, the liquid height of the induced paraffin was measured again. And the gas generation amount was calculated | required using the following formula | equation.
Gas generation amount (μl / g · day) = (liquid height after 3 days (ml) −liquid height after 1 hour (ml)) / (10 (g) × 3 (day)) × 1000
In addition, when the gas generation rate of the negative electrode was 10 μl / g · day or less, it was determined that the corrosion resistance of the negative electrode was good.

(6) Evaluation of discharge performance About each battery, after discharging at 1.5 W for 2 seconds, pulse discharge which repeats the process of discharging at 0.65 W for 28 seconds was performed 10 cycles per hour. Then, the discharge duration until the closed circuit voltage reached 1.05 V was examined.
The evaluation results are shown in Table 1. The discharge capacity in Table 2 was expressed as an index with the discharge capacity of the battery of Comparative Example 2 as 100.

  In the negative electrodes of Examples 1 and 2, zinc alloy powder having a large amount of gas generation was used. However, since an organic anticorrosive was added, the gas generation rate was significantly reduced as compared with the negative electrodes of Comparative Examples 3 and 4. In the batteries of Examples 3 and 4, since highly reactive zinc alloy powder was used, the discharge performance was improved as compared with the batteries of Comparative Examples 1 and 2. Thus, in the batteries of Examples 1 and 2 of the present invention, good discharge performance and negative electrode corrosion resistance were obtained at the same time.

<< Examples 3 to 6 and Comparative Example 5 >>
As the organic anticorrosive agent, a surfactant in which n = 0, X and Y are H, and the value of m is changed as shown in Table 2 in the general formula (2) was used. The surfactant was obtained by an esterification reaction between an alkyl alcohol as an alkyl group-derived precursor and phosphoric acid, and the value of m was changed by changing the carbon number of the alkyl alcohol. Using these organic anticorrosives instead of the organic anticorrosives of Example 1, alkaline batteries were prepared in the same manner as in Example 1, and evaluated in the same manner as described above. The evaluation results are shown in Table 2 together with the results of Example 1.

  In the batteries of Examples 1 and 3-6 in which the hydrophobic group in the phosphoric ester had 1 to 26 carbon atoms, good discharge performance and corrosion resistance of the negative electrode were obtained at the same time. In the battery of Comparative Example 5 in which the number of carbon atoms of the hydrophobic group in the phosphoric acid ester exceeds 26, the adsorptive power to the zinc alloy powder is increased, so that the discharge performance is lowered.

<< Examples 7 to 9 >>
Except for changing the amount of the organic anticorrosive added as shown in Table 3, an alkaline battery was prepared in the same manner as in Example 1 and evaluated in the same manner as described above. The evaluation results are shown in Table 3 together with the results of Example 1 and Comparative Example 3.

  In the batteries of Examples 1 and 7 to 9 in which the organic anticorrosive was added in an amount of 0.005 to 1 part by weight per 100 parts by weight of the zinc alloy powder, good discharge performance and negative electrode corrosion resistance were obtained at the same time. In particular, in the batteries of Examples 1 and 8 in which the addition amount of the organic anticorrosive was 0.05 to 0.2 parts by weight per 100 parts by weight of the zinc alloy powder, excellent liquid leakage resistance and discharge performance were obtained.

<< Examples 10 to 18 and Comparative Examples 6 to 7 >>
Except that the content of each element in the zinc alloy was changed as shown in Table 4, an alkaline battery was produced in the same manner as in Example 1 and evaluated in the same manner as described above. The evaluation results are shown in Table 4 together with the results of Examples 1 and 2.

In the batteries of Examples 1 and 10-13 in which the In content in the zinc alloy was changed, good corrosion resistance and discharge performance of the negative electrode were obtained at the same time, and the gas generation amount of the zinc alloy decreased as the In content increased. . When the In content in the zinc alloy was 250 ppm or more, the gas generation amount was the same.
In the batteries of Examples 2, 14 and 15 in which the Bi content in the zinc alloy was 30 ppm or more, good negative electrode corrosion resistance and discharge performance were obtained at the same time. Moreover, in the battery of Example 14 in which the Bi content in the zinc alloy exceeded 150 ppm, the discharge performance was lowered. From this, it was found that the bismuth content in the zinc alloy is preferably 30 to 150 ppm.
In the batteries of Examples 16 to 18 in which the Al content in the zinc alloy was 5 ppm or more, good negative electrode corrosion resistance and discharge performance were obtained. In the battery of Example 16 in which the Al content in the zinc alloy exceeded 100 ppm, the discharge performance was lowered. From this, it was found that the Al content in the zinc alloy is preferably 5 to 100 ppm.

  In the above embodiment, in general formula (2), X and Y are H and n = 0, but X and Y are each independently H, Na, or K, and m = 0 to 26, If n = 0 to 26 and m + n = 1 to 26 are satisfied, the same effect as described above can be obtained.

  The alkaline battery of the present invention is suitably used as a power source for electronic devices such as communication devices and portable devices.

It is the front view which made a part of one example of the alkaline battery of the present invention into the section. It is a front view of the test container used for the measurement of the gas generation amount of zinc alloy powder.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Battery case 2 Positive electrode mixture 3 Gel-like negative electrode 4 Separator 5 Gasket 6 Negative electrode current collection 7 Bottom plate 8 Exterior label 11, 12 Glassware 11a Storage part 11b Opening cylindrical part 12a Insertion cylindrical part 12b Tubular part 12c Measurement part 13 Zinc Alloy powder 14 Test solution 15 Liquid paraffin

Claims (6)

A positive electrode including a positive electrode active material composed of at least one of manganese dioxide powder and nickel oxyhydroxide powder, a negative electrode including a negative electrode active material and an anionic surfactant, a separator disposed between the positive electrode and the negative electrode, An alkaline electrolyte,
The surfactant is represented by the general formula (1):

(Wherein R ₁ and R ₂ are each independently a hydrogen atom or a hydrocarbon group having 1 to 26 carbon atoms, and the total carbon number of R ₁ and R ₂ is _{1 to} 26). A compound having the structure represented or an alkali metal salt thereof,
An alkaline battery in which the negative electrode active material is a zinc alloy powder having a gas generation rate of 5 to 30 μl / g · day in a 45 ° C. aqueous solution containing 38 wt% potassium hydroxide and 2 wt% zinc oxide. In the general formula (1), R ₁ and R ₂ are each independently a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms, and the total number of carbon atoms of R ₁ and R ₂ is 1 to 6. The alkaline battery according to claim 1. In the general formula (1), R ₁ is H— (CH ₂ ) _m —, R ₂ is H— (CH ₂ ) _n —, m = 0 to 26, n = 0 to 26, and m + n. The alkaline battery according to claim 1, wherein = 1 to 26. In the general formula (1), R ₁ is H— (CH ₂ ) _m —, R ₂ is H— (CH ₂ ) _n —, m = 0 to 6, n = 0 to 6, and m + n. The alkaline battery according to claim 1, wherein = 1 to 6.   The alkaline battery according to claim 1, wherein the negative electrode contains 0.005 to 1 part by weight of the surfactant per 100 parts by weight of the zinc alloy powder.   The said zinc alloy powder is an alkaline battery in any one of Claims 1-5 containing 5-100 ppm aluminum, 30-150 ppm bismuth, and 0-250 ppm indium.

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