JP2007123051A - Alkaline zinc primary battery and alkaline zinc system compound positive electrode mixture used for it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an alkaline zinc primary battery which is superior in high rate discharge characteristics and suppresses deterioration of discharge capacity due to self discharge at the time of storage, and is improved in a sustaining rate of discharge capacity, while adopting an inside-out type structure superior in productivity. <P>SOLUTION: The alkaline zinc primary battery comprises a battery outer package can, a positive electrode mixture which contains at least nickel hydroxide system compound particles and carbon system particles housed and installed in the battery outer package can, and is molded in hollow cylindrical shape, and a negative electrode material which is housed and arranged in the hollow cylinder of the positive electrode mixture through a separator and contains alloy particles having zinc as a main component. The positive electrode mixture contains a compound made of at least one kind selected from a group of Mg, Ca, Yb, Er, Mo, and W. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to an alkaline zinc primary battery, and more particularly, to an alkaline zinc primary battery with improved discharge capacity by storage and an alkaline zinc compound positive electrode mixture used in the battery.

  For example, alkaline manganese primary batteries are used as power sources for portable electronic devices such as portable radios and cassette recorders. In addition, in the configuration of this type of alkaline primary battery, for example, an alkaline manganese primary battery, it is also known to reduce the cost by making the battery element (electromotive part) an inside-out type structure.

  That is, the positive electrode is formed into a hollow cylindrical shape, and a bottomed cylindrical separator is inserted and arranged in the hollow, and an inside-out type structure in which the negative electrode material is filled in the bottomed cylindrical separator is formed into a sheet shape. Compared with the case of adopting a spiral structure in which a laminate of the positive electrode, separator and negative electrode is wound, productivity is improved, and as a result, a high-capacity alkaline zinc primary battery can be provided at low cost.

  As described above, when the battery element is a primary battery with an inside-out type structure, it is advantageous in terms of productivity and cost reduction, but the facing area between the positive electrode and the negative electrode is smaller than in the case of a spiral type structure. Therefore, generally, there is a problem that the high rate discharge characteristic is inferior.

  Therefore, the high rate discharge capacity is improved by using a positive electrode active material in which zinc and cobalt alone or both are co-crystallized with nickel hydroxide particles as the positive electrode active material of the alkaline zinc primary battery for improving the high rate discharge capacity. It has been tried. An alkaline zinc primary battery using this nickel-based compound is characterized by high capacity, excellent high rate discharge characteristics, and high energy density per unit weight.

It is also known to use a positive electrode active material obtained by adding the nickel compound to manganese dioxide as an alkaline battery (see Patent Document 1). However, this nickel hydroxide compound has a problem that it is more reducible than the manganese oxide that is the positive electrode active material of the alkaline manganese primary battery, causes self-discharge during storage, and decreases the discharge capacity. It was. In Patent Document 1, in order to solve this, it is described that zinc oxide or the like is added to the positive electrode active material. However, in a battery using a manganese dioxide-nickel hydroxide compound as the positive electrode active material, It has been difficult to solve this problem to a practical extent.
JP 2001-15106 A

As described above, although it is an alkaline zinc primary battery using a nickel-based positive electrode active material which is superior in high rate discharge characteristics as compared to an alkaline manganese primary battery, it is still insufficient for practical use in terms of storage stability. The present invention has been made in response to the above circumstances, while taking an inside-out type structure with excellent productivity, is excellent in high rate discharge characteristics, and suppresses a decrease in discharge capacity due to self-discharge during storage, It aims at improving the maintenance rate of discharge capacity.

  That is, the present invention includes a battery outer can, a positive electrode mixture containing nickel hydroxide compound particles and carbon particles housed and mounted in the battery outer can and formed into a hollow cylindrical shape, and the positive electrode mixture An alkaline zinc primary battery having a negative electrode material containing zinc-based alloy particles housed and disposed in a hollow cylinder of the cathode, wherein the positive electrode mixture is Mg, Ca, Y, Yb, An alkaline zinc primary battery comprising a positive electrode mixture additive component comprising a compound of at least one element selected from the group consisting of Er, Mo and W.

  In the present invention, the amount of electrolyte consumed by self-discharge of the positive electrode by adding a compound of at least one element selected from Mg, Ca, Y, Yb, Er, Mo, and W to the positive electrode mixture. By reducing the amount of electrolyte that moves from the negative electrode to the positive electrode and maintaining the amount of electrolyte contained in the negative electrode, the discharge capacity is prevented from decreasing due to storage, and the discharge capacity retention rate is improved. Is.

In the present invention, the positive electrode mixture is at least one selected from MgF ₂ , CaF ₂ , Er ₂ O ₃ , Y ₂ O ₃ , Yb ₂ O ₃ , K ₂ MoO ₄ , and K ₂ WO _4. As an additive component, the oxygen overvoltage of the positive electrode is increased, the reducibility of nickel oxyhydroxide is weakened, that is, the oxygen gas generation reaction, which is the decomposition of water in the electrolyte, is reduced, thereby suppressing self-discharge, There is an effect of maintaining the discharge capacity. In the present invention, the amount of the positive electrode mixture addition component is preferably 0.1 to 2.0% by mass with respect to the positive electrode mixture. When the amount of the positive electrode mixture addition component is below this range, the desired effect of maintaining the discharge capacity retention rate is not exhibited. On the other hand, when the amount of the compound exceeds this range, the electrical resistance of the positive electrode mixture increases, and the battery characteristics deteriorate.

Furthermore, in the present invention, as the nickel hydroxide compound, zinc and cobalt alone or nickel oxyhydroxide obtained by co-crystallizing these is stable without changing the crystal structure even at a low electrolyte ratio. Since discharge can be performed, it is preferable.
Furthermore, in the present invention, the nickel hydroxide compound particles may be zinc oxycobalt alone or nickel oxyhydroxide obtained by eutectic crystallizing, improving the electrical conductivity of the whole positive electrode, The rate discharge characteristic is improved, which is preferable. In the present invention, the positive electrode mixture may be at least two selected from MgF ₂ , CaF ₂ , Er ₂ O ₃ , Y ₂ O ₃ , Yb ₂ O ₃ , K ₂ MoO ₄ , and K ₂ WO _4. When added as an additive component, a reduction in discharge capacity due to storage is further prevented, and an improvement in discharge capacity retention rate is achieved. In this case, it is desirable that at least two selected from Er ₂ O ₃ , Y ₂ O ₃ , and Yb ₂ O ₃ are used as additive components. By selecting such a material as the positive electrode active material, it is possible to realize an alkaline zinc primary battery having excellent high rate discharge characteristics as compared with an alkaline manganese zinc primary battery.

According to the present invention described above, in an alkaline zinc primary battery using a nickel-based compound as a positive electrode active material, by adding a compound such as Yb ₂ O ₃ , MgF ₂ to the positive electrode mixture, Self-discharge can be suppressed and the discharge capacity can be effectively prevented from decreasing after storage.

(Battery structure)
Hereinafter, detailed embodiments of the battery of the present invention will be described in detail with reference to the drawings. FIG. 1 shows that the present invention is applied to a JIS standard LR6 type (AA) battery called a so-called inside-out structure (a structure in which the battery can body is on the positive electrode side and the battery lid side is on the negative electrode side). It is an example.

  In FIG. 1, 1 is a battery outer can made of a bottomed cylindrical metal that also serves as a positive electrode terminal, and a positive electrode mixture 2 containing a hollow cylindrical positive electrode active material is accommodated inside the battery outer can 1. Yes. The hollow inside of the positive electrode mixture 2 is filled with a gel-like zinc negative electrode material 4 through a bottomed cylindrical separator 3 made of a nonwoven fabric or the like. A negative electrode current collector rod 5 made of a metal rod is inserted into the negative electrode material 4, and one end of the negative electrode current collector rod 5 protrudes from the surface of the negative electrode material 4 to serve as a ring-shaped metal plate 7 and a cathode terminal. 8 is electrically connected. An insulating gasket 6 made of a double annular plastic resin is disposed on the inner surface of the battery outer can 1 serving as the positive electrode and the outer peripheral surface of the protruding portion of the negative electrode current collecting rod 5, and these are insulated. Further, the opening of the battery outer can 1 is caulked and sealed in a liquid-tight manner.

  Hereinafter, the positive electrode mixture, the negative electrode material, the electrolytic solution, and the separator used in the nickel hydroxide-based alkaline zinc primary battery of the present invention will be described in detail.

(1) Positive electrode mixture The positive electrode mixture of the present invention includes a positive electrode active material composed of nickel hydroxide-based compound particles, a conductive material composed of a carbon-based material such as graphite, an alkaline electrolyte that is the aqueous solution, and a binder as necessary. , And lubricants. As described above, the positive electrode mixture of the present invention is characterized in that it contains a compound of at least one element selected from the group consisting of Mg, Ca, Y, Yb, Er, Mo, and W. As the _{compounds, MgF 2, CaF 2, Y} 2 O 3, Yb 2 O 3, Er 2 O 3, K 2 is desirably at least one selected from the group consisting of MoO ₄ and _K 2 WO _4. These compounds are mixed in the positive electrode mixture in the form of particles. The average particle diameter is preferably in the range of 0.1 to 10 μm. These compounds are dissolved in the electrolytic solution and achieve the function of suppressing self-discharge for the first time. For this reason, those having a small particle size with a high dissolution rate in the electrolytic solution are preferable, but those having an average particle size below the above range are difficult to handle and are not practical.

(Positive electrode active material)
The nickel hydroxide-based compound, which is the positive electrode active material used in the present invention, is a nickel oxyhydroxide obtained by oxidizing part or all of nickel hydroxide so that it can be discharged immediately after charging without being charged. Is desirable. In the present invention, the discharge reaction at the positive electrode of a battery using a nickel oxyhydroxide compound as the positive electrode active material is represented by the following chemical formula.
NiOOH + H ₂ O + e ⁻ → Ni (OH) ₂ + OH ⁻
The nickel oxyhydroxide may be a trivalent β-nickel oxyhydroxide or γ-nickel oxyhydroxide having a valence of nickel atoms, or a tetravalent nickel atom which is the valence of the nickel atom of nickel hydroxide. And a compound having a trivalent intermediate valence of a nickel atom which is completely an oxyhydroxide.

  Further, the nickel hydroxide-based compound itself that is the positive electrode active material may be eutectic with zinc or cobalt alone or both. This positive electrode active material is characterized in that stable discharge can be performed even at a low electrolyte ratio. The amount of zinc or cobalt to be eutectic in this nickel hydroxide compound is preferably in the range of 4 to 12%. This is because if the amount of zinc is below this range, there will be a problem of lowering the utilization factor, and if it exceeds this range, there will be a problem that the capacity density will decrease due to a decrease in specific gravity.

(Carbon-based particles)
Moreover, in this invention, it is preferable to mix | blend carbon-type particle | grains in the said positive mix, and to improve electroconductivity. Examples of the carbon-based particles used in the present invention include acetylene black, carbon black, artificial graphite, and natural graphite. Graphite having an average particle diameter of 5 to 40 μm is particularly preferable. The reason for this is that when the average particle size falls below this range, the ability to bind the positive electrode mixture component inherent to graphite decreases, and the strength of the formed positive electrode mixture decreases, producing a battery. This is because there is not only a problem in the workability, but also the conductivity of the positive electrode mixture is lowered. On the other hand, when the average particle diameter of the graphite exceeds the above range, the diameter becomes larger than that of the active material particles, so that the conductivity is lowered. In the present invention, the content of the graphite particles in the positive electrode mixture is desirably 10% by mass or less. If the graphite particle content in the positive electrode mixture is excessively increased, the amount of the positive electrode active material that can be filled in the limited volume of the metal can itself decreases, and the carbonate ions that are generated when the graphite particles are oxidized. This is because the self-discharge is accelerated and the discharge capacity is reduced. For this purpose, the content of carbon particles in the positive electrode mixture is preferably 10% by mass or less, more preferably 7% by mass or less.

(Other additive ingredients)
The binder is blended in order to bind the positive electrode mixture constituents and improve the shape retention of the positive electrode mixture molded body. For example, polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVdF), PVdF Modified PVdF in which at least one of hydrogen or fluorine is substituted with another substituent, a copolymer of vinylidene fluoride-6-propylene fluoride, a terpolymer of polyvinylidene fluoride-tetrafluoroethylene-6-propylene fluoride A coalescence or the like can be used. These binder components are suitably used in the range of 0.05 to 0.5 mass% with respect to the positive electrode mixture. In addition, a lubricant for improving workability at the time of forming the positive electrode mixture can be added to the positive electrode mixture. As this lubricant, stearic acid compounds such as zinc stearate, calcium stearate, and ethylene bisstearamide are preferable. The addition amount is suitably in the range of 0.05 to 0.5% by mass with respect to the positive electrode mixture.

(Formation of positive electrode compact)
The positive electrode mixture is mixed, and is formed into a hollow cylinder having an outer diameter substantially equal to the inner diameter of the battery outer can made of metal by pressing. In the formed positive electrode mixture, the positive electrode active material particles and the conductive material particles are bound to each other, and the grain boundary between the particles is filled with the electrolytic solution. The nickel hydroxide compound particles of the present invention are formed into a positive electrode by the following steps.

  1) Mixing of the positive electrode mixture component The positive electrode mixture is obtained by mixing the positive electrode active material with the conductive material, binder, lubricant, electrolyte, and the like, which are the positive electrode mixture additives described above. The electrolytic solution is used to increase the ionic conductivity in the positive electrode mixture and to improve the moldability. It is preferable to use the same electrolytic solution as the electrolytic solution used for maintaining ionic conduction between the positive electrode and the negative electrode of the battery. A preferred electrolyte is a 40% aqueous KOH solution. The mixing ratio of these positive electrode mixture components is 90 to 92: 4 to 6: 0.05 to 0.5: 0.05 as a positive electrode active material: conductive agent: binder: lubricant: electrolytic solution in mass ratio. A blending ratio of 0.30: 4-6 is preferred. These components are mixed by a stirrer such as a rotary mixer or a Henschel mixer.

2) Compression granulation classification step The positive electrode mixture blended in the above step is then compressed and pressed by a roller compactor to increase the packing density for granulation.
The positive electrode mixture that has been subjected to the roller compaction treatment is in the form of a compressed mass. In order to produce a molded body using this, it is necessary to granulate once into a granule. For this purpose, granulation is performed by a granulator using twin rolls having protrusions fitted to the roll surface.

  The positive electrode mixture particles obtained in the above step are classified according to their sizes. In this invention, it can be set as the positive electrode mixture molded object with a high packing density by setting it as the particle | grains of the range of 200-800 micrometers. When the granulated powder of less than 200 μm is molded, it takes time to measure the granulated powder and is not suitable. Further, granulated powder exceeding 800 μm is not suitable because the weight of the molded product varies when the mold is formed.

3) Molding The positive electrode mixture particles granulated in the above process are then molded into a positive electrode molded body using a mold. The inside-out type positive electrode mixture has a hollow cylindrical shape, has a central mandrel, and fills the positive electrode mixture particles in a cylindrical mold having a required volume, and press-fits the male type. By doing so, molding is performed. The molding pressure at this time is preferably a pressure of 0.5 × 10 ^{8 to} 9.8 × 10 ⁸ Pa. When the molding pressure is lower than the above range, the required filling density of the positive electrode mixture cannot be obtained, and it becomes difficult to ensure the contact between the particles. Therefore, when the battery is used, a predetermined discharge capacity cannot be obtained. On the other hand, when the molding pressure exceeds the above range, the electrolytic solution is less likely to penetrate into the positive electrode mixture, and the utilization rate is lowered.

(2) Negative electrode material The negative electrode material used in the present invention is a negative electrode material mainly composed of a zinc alloy, which is a negative electrode active material, and zinc gel used in known alkaline manganese primary batteries can be used. This negative electrode material is preferably in the form of a gel in terms of handling. In order to make the negative electrode into a gel, it can be easily made into a gel by dispersing a zinc alloy as a negative electrode active material in a gel electrolyte prepared from an electrolyte and a thickener.

  The zinc alloy used in the present invention may be a zinc alloy that does not contain mercury and lead, which is known as a non-anneaded zinc alloy. Specifically, a zinc alloy containing 0.01 to 0.06 mass% indium, 0.005 to 0.02 mass% bismuth, and 0.0035 to 0.015 mass% aluminum has an effect of suppressing generation of hydrogen gas. There is desirable. In particular, indium and bismuth are desirable for improving the discharge performance. The reason for using a zinc alloy instead of pure zinc as the negative electrode active substance is that the self-dissolution rate in the alkaline electrolyte is slowed down to suppress hydrogen gas generation inside the battery when it is used as a sealed battery product. This is to prevent accidents caused by liquids.

  Moreover, it is desirable that the shape of the zinc alloy is powdery so that the surface area can be increased to cope with a large current discharge. In the present invention, the preferred average particle diameter of the zinc alloy is preferably in the range of 100 to 350 μm. When the average particle diameter of the zinc alloy exceeds the above range, the surface area becomes relatively small and it becomes difficult to cope with a large current discharge. Also, if the average particle size is below the above range, handling during battery assembly becomes difficult, and it becomes difficult not only to mix uniformly with the electrolyte and gelling agent, but also because the surface is active, it is oxidized. It is easy and unstable.

  Moreover, as a thickener used in this invention, polyvinyl alcohol, polyacrylate, CMC, alginic acid, etc. can be used. In particular, sodium polyacrylate is preferable because of its excellent water absorption ratio with respect to a strong alkaline aqueous solution.

(3) Electrolytic Solution The electrolytic solution used in the present invention is preferably an aqueous solution using an alkali salt such as potassium hydroxide, sodium hydroxide or lithium hydroxide as a solute, and particularly preferably potassium hydroxide. In the present invention, the alkaline salt such as potassium hydroxide is dissolved in water to form an electrolytic solution. It is desirable to add a zinc compound to the electrolytic solution. Such zinc compounds include compounds such as zinc oxide and zinc hydroxide, with zinc oxide being particularly preferred.

  The alkaline aqueous solution containing at least a zinc compound is used as the electrolytic solution because the zinc alloy self-dissolution in the alkaline aqueous solution is remarkably less than that of the acidic electrolytic solution, and further in the alkaline electrolytic solution of the zinc alloy. This is to further suppress the self-dissolution of zinc by dissolving a zinc compound, for example, zinc oxide, and pre-existing zinc ions.

(4) Separator The separator used in the present invention is composed of cellulose fibers and nonwoven fabrics such as polyvinyl alcohol fibers, woven fabrics, and papermaking. In these fibers, cellulose fibers have a good affinity with alkaline electrolytes, and are therefore used to increase liquid retention, while polyvinyl alcohol fibers are excellent in alkali resistance. When used in combination, a separator having a good balance of these characteristics can be obtained. In the present invention, these cellulose fibers and polyvinyl alcohol fibers may be made by mixing the respective fibers, or may be pasted together after making each paper separately. In order to use this separator paper as a separator, the separator paper is wound and the bottom is bonded to form a bottomed cylindrical shape. At this time, the side portions of the wound separator paper may be bonded. This bonding may be performed by heat bonding after the separator paper is formed, or an adhesive may be used. When an adhesive is used, it must be a chemical-resistant adhesive.

[Example 1]
(Preparation of positive electrode)
An average particle diameter of 3 μm is added to 90 parts by mass of nickel hydroxide particles of the positive electrode active material described above and 5.4 parts by mass of graphite powder having a specific surface area of 3.4 m ² / g and 0.1 part by mass of polyethylene resin as a binder. MgF ₂ particles are added at a ratio of 0.5% by mass with respect to the positive electrode mixture, and stirred and mixed for 10 minutes. Thereafter, 4.6 parts by mass of a 40% by mass aqueous potassium hydroxide solution is added and mixed for 30 minutes in a general-purpose mixing container to obtain a mixture. Subsequently, this mixture is pressure-molded into a hollow cylindrical shape having an outer diameter of 13 mm, an inner diameter of 9 mm, and a height (length) of 13 mm to produce a positive electrode mixture pellet.

(Preparation of negative electrode)
Polyacrylic acid (gelling agent) is added to 65 parts by mass of zinc alloy powder having an average particle size of 100 to 300 μm including 0.01 parts by mass of indium, 0.01 parts by mass of bismuth and 0.003 parts by mass of aluminum, and mixed for general purpose. A uniform mixing system was obtained by stirring and mixing in a container. To this, an alkaline electrolyte (40% KOH, 4% ZnO) and a gelling agent were added and mixed to prepare a gelled negative electrode material.

(Battery assembly)
Next, an AA alkaline zinc primary battery whose schematic configuration is shown in cross section in FIG. 1 is assembled by a conventional technique using the produced positive electrode mixture pellet and the gelled negative electrode. In FIG. 1, reference numeral 1 denotes a bottomed cylindrical metal can (exterior can) that also serves as a positive electrode terminal. In the cylindrical hollow of the metal can 1, three positive electrode mixture pellets are stacked and pressed again. The molded positive electrode mixture 2 is filled and mounted. In addition, the hollow portion of the positive electrode mixture 2 is provided with a bottomed cylindrical separator 3 made of a nonwoven fabric of acetalized polyvinyl alcohol fibers, and the gelled negative electrode 4 is filled inside the separator 3.

  One end side of a brass negative electrode current collector rod 5 is inserted and arranged in the gelled negative electrode 4, and the outer peripheral surface of the other end side protruding from the gel negative electrode 4 of the negative electrode current collector rod 5 and metal A double annular insulating gasket 6 made of polyamide resin is disposed between the inner peripheral surfaces of the can 1. Further, a ring-shaped metal plate 7 is fitted and disposed between the double rings of the insulating gasket 6, and a hat-shaped metal sealing plate 8 that also serves as a negative electrode terminal contacts the tip of the negative electrode current collector rod 5. It is an arrangement configuration. In addition, the opening edge of the metal can 1 is sealed with the insulating gasket 6 and the metal sealing plate 8 by bending the opening edge of the metal can 1 inward.

(Evaluation)
About the obtained battery, it stored at normal temperature and measured the discharge capacity after progress for a predetermined period. The results are shown in Table 1. As is apparent from this table, the addition of Y ₂ O ₃ alone does not greatly improve the discharge capacity after storage at room temperature and after a predetermined period of time. However, in addition to Y ₂ O ₃ , Er ₂ O ₃ as described later. , Yb ₂ O ₃ is added, a significant improvement is observed.

[Examples 2 to 7]
As compound added to the positive electrode _{mixture, CaF 2, Yb 2 O 3} , Er 2 O 3, K 2 MoO 4, and except for the use of _K 2 WO ₄ is to manufacture a battery in the same manner as in Example 1 In the same manner as in Example 1, the capacity retention rate after storage at room temperature was measured. The results are also shown in Table 12.

[Comparative Example 1]
A battery was produced in the same manner as in Example 1 except that MgF ₂ particles were not added to the positive electrode mixture in Example 1, and the capacity retention rate was measured in the same manner as in Example 1. The results are also shown in Table 1.

  As is clear from the above results, the battery of Comparative Example 1 in which the compound to be added to the positive electrode mixture of the present invention was not added was reduced to 77.7% after 720 days of storage. In the examples in which the compound of the present invention was added, each battery maintained a capacity exceeding 80%.

[Examples 8 to 14]
A battery was manufactured in the same manner as in Example 1 except that the compounds shown in Table 2 were used as components to be added to the positive electrode mixture, and the blending amounts thereof were adjusted as shown in Table 2. It was measured. The results are shown in Table 2.
As is apparent from the results, the discharge capacity was improved when the compound addition amount was in the range of 0.1 to 2% by mass.

[Examples 15 to 38]
As a component added to the positive electrode mixture, the compounds shown in Table 3 (two kinds selected from Er ₂ O ₃ , Y ₂ O ₃ , and Yb ₂ O ₃ ) were used, and the blending amounts thereof were also adjusted as shown in Table 3. A battery was manufactured in the same manner as in Example 1 except that the discharge capacity was measured.
The results are shown in Table 4. For comparison, Comparative Examples 2 to 4 (containing one kind of Y ₂ O ₃ / Yb ₂ O ₃ / Er ₂ O ₃ ) and Reference Examples 1 to 3 (Y ₂ O ₃ / Yb ₂ O) ₃ / Er ₂ O ₃ is included, and the mixing ratio of Y ₂ O ₃ is not in the range of 25 to 99 mass%, or the mixing ratio of Yb ₂ O ₃ is 25 to 99 mass%. Those that are not in the range are also shown.

As is apparent from this result, the discharge capacity is improved when the amount of the two kinds of compounds selected from Er ₂ O ₃ , Y ₂ O ₃ and Yb ₂ O ₃ is in the range of 0.1 to 2% by mass. It was seen.

[Comparative Example 5]
A battery was fabricated in the same manner as in Example 1 using an active material in which nickel oxyhydroxide was added to manganese dioxide in an amount of 40% by mass with respect to the positive electrode active material as the positive electrode active material.
With respect to this battery, the battery characteristics were evaluated in the same manner as in Example 1. The results are shown in Table 5. In Table 5, the values of the discharge capacity and the capacity retention rate are expressed as a ratio when the result of Example 1 is 100%.
As can be seen from Table 1 and Table 5, in the battery using the manganese dioxide positive electrode active material to which nickel oxyhydroxide is added, there is room for improvement in battery capacity characteristics as compared with nickel oxyhydroxide. It was.

Sectional drawing which shows an example of the inside out type | mold battery suitable for applying this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Metal container 2 ... Positive electrode mixture 3 ... Separator 4 ... Gel-like negative electrode 5 ... Negative electrode current collecting rod 6 ... Insulating gasket 7 ... Metal plate 8 ... Metal sealing plate

Claims (9)

A battery outer can, a positive electrode mixture containing at least nickel hydroxide compound particles and carbon particles accommodated and mounted in the battery outer can, and formed into a hollow cylindrical shape; and a hollow cylinder of the positive electrode mixture In an alkaline zinc primary battery having a negative electrode material containing alloy particles containing zinc as a main component and disposed via a separator,
The alkaline zinc primary battery, wherein the positive electrode mixture contains a positive electrode mixture additive component composed of a compound of at least one element selected from the group consisting of Mg, Ca, Y, Yb, Er, Mo, and W. The positive electrode mixture additive _component, in _{MgF 2, CaF 2, Y 2} O 3, Yb 2 O 3, Er 2 O 3, K 2 MoO 4, and at least one compound selected from the group consisting of _K 2 WO ₄ The alkaline zinc primary battery according to claim 1, wherein:   3. The alkaline zinc primary battery according to claim 1, wherein the amount of the positive electrode mixture additive component is 0.1 to 2% by mass with respect to the positive electrode mixture. The positive electrode mixture addition component is at least two compounds selected from the group of Y ₂ O ₃ , Yb ₂ O ₃ and Er ₂ O ₃ , and the amount of the two types of mixture is based on the positive electrode mixture The alkaline zinc primary battery according to claim 1, wherein the content is 0.1 to 2% by mass. The mixing ratio of the positive electrode mixture additive component composed of Y ₂ O ₃ is 25 to 99 mass%, or the mixing ratio of the positive electrode mixture additive component composed of Yb ₂ O ₃ is 25 to 99 mass%. The alkaline zinc primary battery according to claim 4, wherein: The _Y 2 _O 3 contained in the _mixture, Yb ₂ O 3, _Er average particle size of 2 _{O 3} consisting of compounds according to claim 4 alkaline zinc one described order, characterized in that both are 0.1~10μm battery.   2. The alkaline zinc primary battery according to claim 1, wherein the nickel hydroxide-based compound is zinc and cobalt alone or nickel oxyhydroxide obtained by eutectic crystallizing them.   A positive electrode mixture containing nickel hydroxide compound particles and carbon particles, wherein the positive electrode mixture is a compound of at least one element selected from the group consisting of Mg, Ca, Y, Yb, Er, Mo, and W An alkali zinc-based compound positive electrode mixture characterized by comprising A positive electrode mixture containing nickel hydroxide compound particles and carbon particles, wherein the positive electrode mixture is a compound of at least two elements selected from the group consisting of Mg, Ca, Y, Yb, Er, Mo, and W And an amount of the positive electrode mixture additive component is 0.1 to 2% by mass with respect to the positive electrode mixture.

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