JPH08293309A - Manganese battery - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a manganese dry battery which has the same performance as the use of mercury, cadmium and lead without using harmful substances at all. A manganese dry battery using a zinc material containing 0.001 to 0.25 wt% of Ti or 0.002 to 0.500 wt% of Zr in a zinc alloy containing 0.004 to 0.75 wt% of In. A zinc can 12 for use is prepared, and a separator 10 coated with a sizing agent containing 0.1 to 8 wt% of InCl ₃ is provided on the inner surface of the zinc can. Inside the separator, manganese dioxide and acetylene black etc. are electrically conductive. A positive electrode mixture 14 prepared by mixing an electrolytic carbonaceous material with an electrolyte solution having a ZnCl ₂ concentration of 35 to 50 wt% is filled with a carbon rod 16 as a current collector at the center of the positive electrode mixture.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention provides a high performance manganese dry battery without adding harmful substances such as mercury, cadmium or lead.

[0002]

2. Description of the Related Art In a conventional manganese dry battery, about 0.15 wt% lead and about 0.05 wt% cadmium are added to pure zinc in order to improve workability, mechanical strength and corrosion resistance for producing a zinc can. Negative electrode zinc cans were made from the above zinc-based alloy, or the surface of the zinc cans was amalgamated with mercury.

Further, the electrolyte is 25 to 30 wt.
% ZnCl ₃ and about 5 wt% NH ₄ Cl were used.

[0004]

However, a battery obtained by adding a harmful substance such as mercury, cadmium, or lead to a zinc can causes a pollution problem when it is discarded.
Although it is desired to develop a battery that does not use any of these harmful substances, it is still necessary to add about 0.4 wt% of lead in recent years in order to improve the corrosion resistance.

Further, it has been proposed to make a zinc can from a zinc alloy in which only a small amount of In is added to pure zinc without adding any of the above-mentioned harmful substances, but such a zinc can is processed. However, it is inferior in the amount of zinc corrosion after high temperature storage, long-term use conditions (memory backup applications), and the pulse discharge characteristics that have recently been increasing. Further, since the open circuit voltage during the assembly process of the dry battery changes with time, a time required for selecting defects is required.

In view of the above-mentioned problems, the present applicant has previously found that pure zinc is added to In (indium) and Ti (titanium).
Alternatively, a method for producing a negative electrode zinc can of a battery from a zinc-based alloy that does not significantly contain harmful substances such as mercury, cadmium, and lead by adding a trace amount of Zr (zirconium) is provided. In the negative electrode zinc can manufactured by this method, the corrosion resistance was improved by adding indium, and the rolling workability was improved by adding titanium or zirconium.

However, in the above method, the amount of indium that can be added to pure zinc is still limited to a small amount, and it is not sufficiently satisfactory in terms of corrosion resistance.

Therefore, the present invention has been made in view of the above problems, and the purpose thereof is not to use the above-mentioned harmful substances at all, but it has the same level of performance as when using this, It is an object of the present invention to provide a manganese dry battery having improved corrosion resistance.

[0009]

In order to achieve the above object, in the manganese dry battery of the present invention, I is added to pure zinc without adding harmful substances such as mercury, cadmium or lead.
A zinc can for a manganese dry battery using a zinc material in which 0.001 to 0.25 wt% of Ti or 0.002 to 0.500 wt% of Zr is added to a zinc alloy formed by adding n of 0.004 to 0.75 wt% And a separator coated with a sizing agent containing 0.1 to 8 wt% of InCl ₃ added to the inner surface of the zinc can, and the conductive carbonaceous material such as manganese dioxide and acetylene black is provided inside the separator. To Z
A positive electrode mixture prepared by mixing an electrolytic solution having an nCl ₂ concentration of 35 to 50 wt% is filled, and a carbon rod is inserted as a current collector at the center of the positive electrode mixture.

[0010]

[Function] By adding indium to the paste of the separator that comes into contact with the zinc can, the indium in the paste is replaced on the surface of the zinc can, and acts in the same manner as mercury, and the indium added to the zinc can Effectively suppresses corrosion of zinc can with titanium or zirconium. In addition, the ZnCl ₂ concentration in the electrolytic solution is set to 35 to 50 wt% to accelerate the anticorrosion effect of indium, and to stabilize the negative electrode zinc interface state quickly to stabilize the open circuit voltage during the assembly process early. Turn into

[0011]

[Examples] The present applicant previously filed Japanese Patent Application No. 7-13814 with 0.004 to 0.75 wt% of In (indium) in pure zinc.
And a method for manufacturing a negative electrode zinc can of a battery from a zinc-based alloy containing 0.001 to 0.25% by weight of Ti (titanium) and not containing harmful substances such as mercury, cadmium and lead. In the negative electrode zinc can manufactured by this method, the corrosion resistance can be improved by adding indium, and the rolling workability can be improved by adding titanium.

In addition to the above-mentioned application, the present applicant has previously filed Japanese Patent Application No. 7-13815 with 0.004 to 0.800% by weight of In (indium) in pure zinc and Zr (zirconium).
The present invention provides a method for manufacturing a negative electrode zinc can of a battery from a zinc-based alloy containing 0.002 to 0.500% by weight of Al and not containing harmful substances such as mercury, cadmium and lead. In the negative electrode zinc can manufactured by this method, corrosion resistance can be improved by adding indium similarly to the above zinc can, and rolling workability can be improved by adding zirconium.

As is apparent from the above-mentioned application, the amounts of indium and titanium or zirconium added to pure zinc were limited to the above range in order to satisfy both conditions of corrosion resistance and workability of the zinc can. However, in the present invention, in order to further improve the corrosion resistance of the zinc can, indium is added to the paste of the separator that comes into contact with the zinc can. As a result, the indium in the paste is replaced on the surface of the zinc can and acts like mercury, effectively suppressing corrosion of the zinc can.

The amount of indium added is 0.1 to 8.0% by weight with respect to the paste applied to the separator, so that the amount of indium added may be less than 0.1% or more than 8.0%. However, the desired effect cannot be obtained.

Further, in the present invention, the concentration of ZnCl ₂ in the electrolytic solution is set to 35 to 50 wt% to accelerate the anticorrosion effect of indium, thereby promoting the swelling of starch in the paste of the separator, It quickly stabilizes the state of the negative electrode zinc interface, and at the same time suppresses the amount of corrosion due to self-discharge during storage. In addition, early stabilization of the interface state of the negative electrode zinc stabilizes the open circuit voltage during the assembly process at an early stage.

Specific examples of the present invention will be described below.

The battery used is R03 as shown in FIG.
Manganese dry battery, in the figure, 10 is a separator, 1
2 is a bottomed cylindrical negative electrode zinc can, and 14 is a positive electrode mixture containing manganese dioxide as an active material. The positive electrode mixture 14 is wrapped in the separator 10 and filled in the negative electrode zinc can 12, and the positive electrode carbon rod 16 is inserted in the center thereof. The opening of the zinc can 12 is sealed with a sealing gasket 18. The negative electrode terminal plate 20 is applied to the bottom surface of the zinc can 12, and the carbon rod 16
A positive terminal plate 22 is covered on the protruding end of the. A shrink tack label 24 is wound around and adhered to the outer circumference of the zinc can 12.

The positive electrode mixture was obtained by adding 2 parts by weight of acetylene black to 10 parts by weight of electrolytic manganese dioxide and mixing them by dry mixing.
Then, the electrolytic solution of each composition shown below was added and mixed.

As the separator, 53 parts by weight of starch and the like and 157 parts by weight of water and a small amount of salt are mixed, and a small amount of indium salt (InCl ₃ ) is added to the separator and coated on the base paper.
/ M ² . The amount of indium salt added was changed to 0.1% by weight (this sample 1), 1.4% by weight (this sample 2), and 8.0% by weight (this sample 3) with respect to the above mixture. On the other hand, as a comparison, 53 parts by weight of starch and the like and water or a trace amount of salt 15
7 parts by weight, while adding no indium salt (Comparative sample 1), 0.05% by weight of indium salt
What was added (comparative sample 2) and what added indium salt 10.0 wt% (comparative sample 3) were applied to the base paper, and basis weight 3
A comparative sample was prepared at 0 g / m ² .

For a zinc can, a typical In--Ti system is 0.009% by weight of indium with respect to pure zinc and T.
a zinc-based alloy containing 0.024% by weight of i,
A typical In-Zr system is a zinc-based alloy containing 0.015 indium and 0.007% by weight zirconium with respect to pure zinc, and a typical conventional composition is lead.
A zinc-based alloy containing 4% by weight and 0.0005% by weight magnesium was tested.

Regarding the composition of the electrolytic solution in the positive electrode mixture, the conventional composition is ZnCl ₂ / NH ₄ Cl = 27/3.
(% By weight) and ZnCl ₂ /
NH ₄ Cl = 35/0 (wt%) and ZnCl ₂ /
It was tested with NH ₄ Cl = 50/0 (wt%).

Table 1 shows the results of testing the discharge capacity, the corrosion weight loss and the like by combining the above separator, zinc can and positive electrode mixture.

[0023]

[Table 1] As is clear from Table 1 above, indium was added in an amount of 0.1 to 8.0% by weight, as compared with those in Comparative Samples 1 and 2 in which indium was not added and indium was added in an amount of 0.05% by weight. The samples 1 to 3 using the separator have a significantly reduced corrosion weight loss, and the reduction is more remarkable particularly when the content of ZnCl _{2 in} the electrolytic solution is 35 to 50% by weight. On the other hand, indium is 10.0
The comparative sample 3 added by weight% has no difference from the present sample 3, and is uneconomical as the amount of addition increases.

Further, compared with the conventional battery in which the zinc can contains lead, those in which the present samples 1 to 3 were used as the separator and the content of ZnCl _{2 in} the electrolytic solution was 35 to 50% by weight were obtained. The corrosion loss is equal to or less than that of the conventional one, the discharge capacity after storage at 60 ° C. for 20 days is superior to the conventional one, and the pulse discharge cycle is 1.
It is 8 times or more, and some 15 Ω continuous discharge capacities are inferior to the conventional ones, but most of them are more than that.

[0025]

Industrial Applicability As described above, the manganese dry battery of the present invention suppresses the amount of corrosion during storage as compared with the conventional lead-added battery without adding harmful substances, and even under long-term use conditions, Even in the pulse discharge cycle, it can be improved at the same time, the stabilization during the assembly process can be promoted, and the manganese dry battery productivity can be improved.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a manganese dry battery to which the present invention is applied.

[Explanation of symbols]

 10 Separator 12 Negative Electrode Zinc Can 14 Positive Electrode Mixture 16 Carbon Rod

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akihide Izumi 5-6-11 Shimbashi, Minato-ku, Tokyo Fuji Electric Chemical Co., Ltd. (72) Inventor Kazuo Matsui 5-36-11 Shimbashi, Minato-ku, Tokyo Fuji Electric Chemistry Co., Ltd. (72) Inventor Takaaki Yasumura 5-36-11 Shimbashi, Minato-ku, Tokyo Fuji Electric Kagaku Co., Ltd. (72) Yoshiteru Nakagawa 5-36-11 Shimbashi, Minato-ku, Tokyo Fuji Electric Kagaku Within the corporation

Claims (1)

[Claims] 1. In is 0.004 to 0.00 without adding harmful substances such as mercury, cadmium or lead to pure zinc.
0.005% Ti in a zinc alloy formed by adding 0.75 wt%
1 to 0.25 wt% or Zr 0.002 to 0.5
A zinc can for a manganese dry battery was prepared by using a zinc material added with 00 wt%, and InCl ₃ was added to the inner surface of the zinc can by 0.1%.
A separator coated with a paste containing 8 to 8 wt% is disposed, and ZnCl ₂ concentration of 35 to 35 is added to conductive carbonaceous material such as manganese dioxide and acetylene black inside the separator.
Fill a positive electrode mixture prepared by mixing 50 wt% electrolytic solution,
A manganese dry battery characterized in that a carbon rod is inserted as a current collector in the center of the positive electrode mixture.