JPS585965A - Alkaline battery - Google Patents

Abstract

PURPOSE:To obtain an alkaline battery such as an alkaline manganese battery or mercury battery which shows an excellent characteristic when used for a large consumption current, without deteriorating the preservation reliability of the battery, by homogeneously dispersing cellulose powder in the gel-like electrolyte of the battery. CONSTITUTION:The symbol 1 represents a metallic sealing plate also serving as a negative terminal. The symbol 2 represents a sealing gasket which insulates the positive electrode from the negative electrode and seals the opening of a case. The symbol 3 represents a cylindrical metallic case which has a bottom and gives pressure upon a positive mixture 4. A separator 5 is placed on the upper surface of the positive mixture 4, and an electrolyte holding member 6 is placed on the upper surface of the separator 5. The symbol 7 represents a positive ring with which the positive mixture 4 is fixed to the case 3. The symbol 8 represents a negative part which contains amalgamated zinc powder, alkaline electrolyte, and slight amounts of a gelling agent and cellulose powder. By thus dispersing cellulose powder in the negative part 8,the discharge performance of the negative part 8 is remarkably improved especially at low temperature. Besides, the battery has an outstanding preservation capacity, and shows an excellent performance when used for a large consumption current.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to alkaline batteries such as alkaline manganese batteries, mercury batteries, silver oxide batteries, silver peroxide batteries, and nickel-zinc batteries. More specifically, the negative electrode active material is frozen zinc powder, which is dispersed in an alkaline electrolyte containing a gelling agent and an alkaline electrolyte such as potassium hydroxide, large thorium hydroxide, or lithium hydroxide. This invention relates to the improvement of batteries, and provides an alkaline battery that is excellent in use with large current consumption.

Traditionally, this type of alkaline battery has been manufactured as a power source for consumer devices such as cameras and calculators, but with the rapid spread of consumer devices such as electronic lighters, watches, and cameras in recent years, these consumer devices The need for batteries as a power source for batteries is increasing significantly, and different types and sizes of batteries are used depending on the purpose.

The characteristics required of batteries as a power source include the static characteristics inherent in batteries such as open circuit voltage and internal resistance, dynamic characteristics such as closed circuit voltage and discharge capacity during use, and storage characteristics such as leakage resistance. However, with the expansion of battery applications as described above, there is a need for batteries that can provide stable characteristics even with large current consumption.

Conventionally, cellophane, cotton, etc. were placed between the positive and negative electrodes.
The resistance of the battery was stabilized by reducing the thickness of the separator, such as rayon or porous polyethylene, and sufficiently impregnating the separator with electrolyte to stabilize the resistance of the separator. However, according to this method, problems such as tearing of the separator tend to occur during the battery assembly process, and storage stability is also unstable. Also,
The zinc discharge reaction was stabilized by increasing the volume of the gel electrolyte and increasing its ratio to the zinc hydrate powder in the negative electrode, but even with this method, there were problems with leakage resistance during battery storage. There was.

The present invention improves the above-mentioned drawbacks by uniformly dispersing cellulose powder in a gel electrolyte, thereby providing a battery with excellent characteristics for use with large current consumption without impairing storage reliability. be.

The present invention will be explained below with reference to Examples.

The drawing shows a button-type alkaline manganese battery. 01 is a metal sealing plate that also serves as a negative terminal. It is made of copper and stainless steel, or copper, stainless steel, and nickel plated plywood, or nickel plating on the outer surface and nickel plating on the inner surface. It is made of plated metal such as tin that easily alloys with metallic mercury. 2 insulates the positive and negative electrodes, and is made of engineering plastic such as resin and polypropylene resin at the opening of the case. 3 is a cylindrical metal case with a bottom, made of stainless steel or iron with nickel plating applied to the entire surface, and the inner bottom of the case contains a positive electrode mixture prepared by forming a mixed powder of manganese dioxide and graphite into a tablet shape. 4 Fully pressurized.

A separator 6 made of a porous synthetic resin film, such as a porous polypropylene membrane or a cellophane membrane, is disposed on the upper surface of the positive electrode mixture 4, and a separator 6 made of a porous synthetic resin film, such as a porous polypropylene membrane or a cellophane membrane, is further disposed on the upper surface of the separator 6. 07 is a positive electrode ring that fixes the positive electrode mixture to the case, and is equipped with an electrolyte-impregnated material 6 made of non-woven fabric, and the stainless steel ring is made of iron with nickel plating applied to the entire surface. 8
is the negative electrode part, which contains zinc hydrate powder, alkaline electrolyte, some amount of gelling agent, and cellulose powder.

A button-type alkaline manganese battery (J
IS LR44), we prototyped batteries equipped with a negative electrode in which frozen zinc powder was dispersed in a gel electrolyte containing cellulose powder in various proportions.

That is, 3 parts by weight of polyacrylic acid powder was dissolved in 97 parts by weight of an alkaline electrolyte having a potassium hydroxide concentration of 40% by weight and a zinc oxide concentration of 3% by weight to form a gel electrolyte, and various types of electrolytes as shown in Table 1 were added to this. The cellulose powder was uniformly dispersed at a ratio of . Then, 50 parts by weight of frozen zinc powder was dispersed in 60 parts by weight of this gel electrolyte to form a negative electrode. The particle size of the cellulose powder is 01, which is 100 to 200 mex, and the content of the cellulose powder is 7% by weight.
In this case, the fluidity of the electrolyte deteriorated, which caused problems in battery assembly.

Below is the margin: Table 1 The above batteries were tested at 20°C, 0°C and -20°C for 30 minutes.
Table 2 shows a comparison of the duration when discharged at oΩ and the duration when discharged at 3oΩ at 20° C. after one year of storage at room temperature. Note that the discharge end voltage is t, oV at 20℃, and 0.8V at -20℃.
And so.

As is clear from Table 2 in Table 2 in the margin below, the discharge performance is improved in all cases in which cellulose powder is dispersed, and the effect is particularly remarkable at low temperatures. It also has excellent storage capacity. This effect is achieved because cellulose powder having hydrophilic properties is present around the zinc powder, which maintains a liquid electrolyte.Almost the same effect can be obtained even when other alkaline electrolytes are used. It is common to dissolve 0.1 to 10 weight percent zinc in the alkaline electrolyte of this type of battery, and it is preferable to use an electrolyte in which zinc oxide is dissolved. Also, other water-soluble polymers may be used as the gelling agent. As mentioned above, cellulose powder is not used in large quantities, so in order to uniformly disperse it, it is appropriate that the cellulose powder has a particle size smaller than that which can pass through a 60 mesh sieve.

As described above, according to the present invention, an alkaline battery excellent in use with large current consumption can be obtained.

[Brief explanation of the drawing]

The mouth side is a cross-sectional side view of the main parts of the Alkashima/Gan battery according to the embodiment of the present invention. 4... Positive electrode, 6... Separator, 6...
...Liquid-containing material, 8...Negative electrode.

Claims (1)

[Claims] (1) An alkaline battery comprising a negative electrode in which frozen zinc powder is dispersed in a gel electrolyte containing a water-soluble polymer, characterized in that cellulose powder is dispersed in the electrolyte. C2) The alkaline battery according to claim 1, wherein the cellulose powder has a particle size that passes through a 50 mesh sieve, and a content ratio of the cellulose powder in the gel electrolyte is 0.5 to 6.0 by weight.