JPH07335202A - Mn dry battery - Google Patents

Abstract

PURPOSE:To obtain mechanical strength and preservation property equivalent to those of the conventional battery while maintaining anti-corrosion property by containing a lead and a titanium at their specific weight% range in the negative pole zinc can of a dry battery whose active material of the positive pole is Mn di-oxide. CONSTITUTION:A Mn dry battery consist of a positive pole depolarizing mix 1 whose active material is Mn di-oxide, a separator 2, a negative pole zinc can 3, a bottom part insulation paper 4, a carbon bar 5, and a cap integrated sealing plate 6 recurrently serving as a positive terminal, a negative pole terminal board 7, and an exterior can 8. This zinc can 3 is made of zinc alloy containing lead less than of 0.5weight/% and titanium of 0.001 to 0.5weight/%. By adding titanium to zinc, its crystal tissue becomes fine, and the processing property, mechanical strength, and preservation property of a dry battery equivalent to those of the conventional alloy containing the lead and cadmium can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a manganese dry battery, and more particularly to a mercury-cadmium-free manganese dry battery in which a negative electrode zinc alloy is improved to improve mechanical strength and corrosion resistance.

[0002]

2. Description of the Related Art Conventionally, in a manganese dry battery, generally, in order to improve workability and mechanical strength required for making a zinc can also serving as a negative electrode of a manganese dry battery and suppress corrosion of a negative electrode zinc can, Zinc alloys with additions of 03-0.1 wt% cadmium and 0.1-0.3 wt% lead have been used. Of these heavy metals, cadmium is currently produced without any additives because environmental pollution caused by the disposal of used dry batteries is regarded as a problem, but in order to supplement the corrosion resistance and mechanical strength of the negative electrode zinc can, Generally, the amount of lead added is increased to, for example, 0.3 to 0.5% by weight.

[0003]

However, the negative electrode zinc can with an increased amount of lead added has the workability required during can manufacturing.
The mechanical strength was insufficient as compared with conventional negative electrode zinc cans containing lead and cadmium. Although lead is a small amount, it is desirable not to use lead in consideration of environmental pollution.

In view of the above, it is an object of the present invention to provide a manganese dry battery provided with a zinc can having mechanical strength equivalent to that of a conventional negative electrode zinc can containing lead and cadmium while maintaining corrosion resistance. To do. It is another object of the present invention to provide a manganese dry battery having a negative electrode zinc can which has mechanical strength and corrosion resistance equivalent to those of conventional ones and which does not contain lead.

[0005]

The manganese dry battery of the present invention comprises a positive electrode using manganese dioxide as an active material, a negative electrode zinc can and a separator, wherein the zinc can contains 0.5% by weight or less of lead and 0.001%. It consists of a zinc alloy containing .about.0.5% by weight of titanium. Here, the titanium content is more preferably 0.01 to 0.1% by weight. Further, the manganese dry battery of the present invention comprises a positive electrode using manganese dioxide as an active material, a negative electrode zinc can, and a separator, and the zinc can is made of a zinc alloy containing 0.001 to 0.5% by weight of titanium. Is. The titanium content of this zinc alloy is more preferably 0.01 to 0.5% by weight.

[0006]

By adding titanium to zinc, workability and mechanical strength equivalent to those of conventional alloys containing lead and cadmium can be obtained. It is considered that this is because the crystal structure is refined by the addition of titanium.
In a lead alloy containing 0.5% by weight or less of lead, the titanium content is 0.001 to 0.5% by weight, and when not containing lead, the titanium content is 0.01 to 0.5% by weight. The mechanical strength equal to or higher than that of the alloy containing cadmium and cadmium can be obtained, and the storage characteristics of the dry battery equivalent to the conventional one can be obtained.

[0007]

EXAMPLES The present invention will be described in detail below based on examples. Zinc ingot having a purity of 99.99% was melted, and lead and / or titanium was added thereto to prepare a zinc alloy having the composition shown in Table 1. No. 15 to 17 are comparative examples. Using the above zinc alloy, make a zinc can of a dry cell battery,
The mechanical strength was evaluated. That is, as shown in FIG. 2, the negative electrode zinc can 10 is placed on the V-shaped block 11, and a conical pressure terminal 12 is applied at a position 10 mm from the opening of the negative electrode zinc can to apply pressure in the vertical direction. The amount of displacement of the conical pressure terminal in the pressurizing direction and the force applied to the contact point of the conical pressure terminal are recorded by a recorder. With a single size negative electrode zinc can, the displacement is about 4 mm, which is a nearly constant value.
For convenience, the load at the time of displacement of mm is defined as the mechanical strength of the negative electrode zinc can.

Next, in order to evaluate the corrosion resistance of the negative electrode zinc can, a hydrogen gas generation test in an electrolytic solution was conducted. The test method was as follows: 5 ml of 30 wt% zinc chloride and 1.9 wt% ammonium chloride was used as an electrolytic solution, and a negative electrode zinc can cut to a certain weight was immersed in the electrolytic solution and left in an atmosphere of 45 ° C. The gas generation amount on the 3rd day was measured. Also, using each negative electrode zinc can, the zinc chloride type single unit shown in FIG.
A manganese dry battery was produced. Here, 1 is a positive electrode mixture containing manganese dioxide as an active material, 2 is a separator, 3 is a negative electrode zinc can, 4 is bottom insulating paper, 5 is a carbon rod, 6 is a cap integrated sealing plate also serving as a positive electrode terminal, and 7 is Negative electrode terminal plate, 8 shows an outer can. In order to evaluate the storage characteristics of these manganese dry batteries, continuous discharge was performed under a load of 2Ω immediately after production and after storage at 45 ° C. for 3 months, and the discharge duration until reaching 0.9 V was examined. The above results are shown in Tables 1 and 2.

[0009]

[Table 1]

[0010]

[Table 2]

Sample No. in the table. 2 to 5, the addition of 0.001 to 0.5% by weight of titanium to zinc results in No. 2 in which only conventional lead is added. No. 16 in which the mechanical strength is higher than that of the zinc can of No. 16 and the titanium content is 0.01% by weight or more and cadmium is added. Mechanical strengths in excess of 15 can be obtained. No. The amount of titanium added is 0.00
If it is less than 1% by weight, the negative electrode zinc can becomes soft and sufficient mechanical strength cannot be obtained. In addition, No. If the addition amount of titanium of No. 6 exceeds 0.5% by weight, the corrosion resistance of zinc deteriorates.

In the titanium-zinc alloy containing no lead, when the titanium content is 0.01 to 0.5% by weight, the corrosion resistance of the negative electrode zinc can and the storage characteristics of the dry battery are almost the same as those of the conventional zinc can. Is equivalent. In addition, No. 7-
In the case of containing 14 lead, the mechanical strength of the negative electrode zinc can is improved by the addition of titanium. When the titanium content is 0.01 to 0.1% by weight, the negative electrode zinc can has the best mechanical strength, corrosion resistance, and storage characteristics of the dry battery. In the above example, the lead content is set to 0.3% by weight or 0.5% by weight, but in the range of 0.5% by weight or less, almost the same result as above can be obtained.

[0013]

As described above, according to the present invention, the mechanical strength of the negative electrode zinc can can be improved by adding 0.001 to 05% by weight of titanium. Furthermore, an alloy containing lead or a titanium content not containing lead of 0.01 to
By using a negative electrode zinc can with 0.5% by weight,
It is possible to obtain a dry battery having mechanical strength equal to or higher than that of a conventional negative electrode zinc can containing lead and cadmium, and having storage characteristics equivalent to those of conventional ones.

[Brief description of drawings]

FIG. 1 is a front view in which a part of a manganese dry battery according to an embodiment of the present invention is shown in section.

FIG. 2 is a perspective view showing a method for measuring the mechanical strength of a negative electrode zinc can.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Positive electrode mixture 2 Separator 3 Negative zinc can 4 Bottom insulating paper 5 Carbon rod 6 Positive electrode cap integrated sealing plate 7 Negative electrode terminal plate 8 Exterior can 10 Negative zinc can 11 V type block 12 Cone pressure terminal

 ─────────────────────────────────────────────────── ─── Continued front page (72) Inventor Ryohei Ashihara 1006 Kadoma, Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. 72) Inventor Kohei Kubota 2-1-1 Nihombashi Muromachi, Chuo-ku, Tokyo Mitsui Mining & Smelting Co., Ltd. (72) Akira Kato 2-1-1 Nihombashi Muromachi, Chuo-ku, Tokyo Mitsui Mining & Smelting Co., Ltd.

Claims (3)

[Claims] 1. A positive electrode using manganese dioxide as an active material, a negative electrode zinc can, and a separator, wherein the zinc can has a density of 0.1.
A manganese dry battery comprising a zinc alloy containing 5% by weight or less of lead and 0.001 to 0.5% by weight of titanium. 2. A positive electrode using manganese dioxide as an active material, a negative electrode zinc can, and a separator, wherein the zinc can has a capacity of 0.
A manganese dry battery comprising a zinc alloy containing 001 to 0.5% by weight of titanium. 3. The titanium content of the zinc alloy is 0.01
The manganese dry battery according to claim 2, which is about 0.5% by weight.