JPS58155653A - Manufacture of alkaline battery - Google Patents

Abstract

PURPOSE:To provide a long life alkaline battery by cleaning the surface of copper or copper alloy, which is to be in contact with a negative active mass, of a negative current collector with a chemical polishing solution of hydrogen peroxide and sulfuric acid family, and amalgamating this surface with a solution containing a mercury ion. CONSTITUTION:A reverse curl portion 5 of the circumference of a negative case 4 is covered with a synthetic resin jig 6. This case 4 is treated with a chemical polishing solution that the molar ratio of sulfuric acid to hydrogen peroxide is 0.045 for about 2min at room temperature. By this treatment, the exposed surface of copper is polished chemically and harmful foreign matter such as fine metal debris is removed. After the jig 6 is removed, the case 4 is immersed in a mercuric chloride solution acidified with acetic acid to amalgamate the surface of copper. By using this process, electrolyte leakage and rupture is prevented, and a long life battery is provided.

Description

Detailed Description of the Invention This invention uses silver oxide, manganese dioxide, etc. as a positive electrode active material.
The present invention relates to a method for producing an alkaline battery using zinc or the like as a negative electrode active material and an alkaline electrolyte solution.

In general, alkaline batteries have a metal positive electrode capacity that also serves as the positive electrode terminal. After filling the negative electrode active material and alkaline electrolyte into a metal electrode container that also serves as the positive electrode terminal, a separator is interposed, and one synthetic polymer, etc. The two containers are fitted together via an insulating gas get, and the opening of the positive electrode capacitor is curved inward to seal the opening.

For example, in the case of button-type silver oxide batteries, the negative electrode container is generally
A two-layer V-clad plate of stainless steel and steel or copper alloy, or a three-layer V-clad plate of nickel, stainless steel, steel, or copper alloy is processed so that the steel or steel alloy side becomes the inner surface of the container. It was manufactured by

Copper or steel alloy WK of the negative electrode container manufactured in this way
- is to avoid the formation of oxides, the adhesion of dirt and dust, or the adhesion of minute pieces of metal such as stainless steel and nickel during the cladding slope manufacturing process, slit processing punching II/drawing process, etc. I can't. Before battery assembly, pretreatment such as degreasing and cleaning is performed, but if these foreign substances get into scratches on the steel or steel alloy surface, or if they are pressed after adhesion, it is impossible to completely remove them with normal cleaning or other means. It is difficult to remove.

Due to the presence of an alkaline electrolyte, the steel or steel alloy surface of the negative electrode container comes into contact with the zinc chloride of the JIL electrode active material, and is amalgamated and galvanized.

Therefore, even though steel or copper alloy is more dangerous than zinc, hydrogen gas generation is suppressed even if it comes into contact with zinc, so the battery can be sealed.

If foreign matter such as steel, stainless steel, or nickel remains on the steel or steel alloy surface, it will be difficult for these foreign matter to undergo galvanization and galvanization.

It remains exposed. Since these metals have a small hydrogen overvoltage, they generate hydrogen gas when the negative electrode capacity a is filled with alkaline solution and zinc.

Therefore, after one assembly, the inside of the battery is filled with hydrogen gas, which increases the internal pressure of the battery, causing ll liquid or causing the battery to explode, producing hydrogen gas. be.

This invention was made based on the above circumstances.

After cleaning the s-plane of copper or copper alloy that comes into contact with the negative electrode active material of the negative electrode current collector with hydrogen peroxide and sulfuric acid-based chemical polishing liquid, the hydrogen gas is removed by amalgamating with a solution containing mercury ions. It is an object of the present invention to provide a method for manufacturing an alkaline battery which can have a long lifespan without the occurrence of leakage or bursting.

In other words, since it is difficult to remove foreign substances such as fine metal particles attached to the steel or steel alloy of the negative electrode container using normal cleaning methods, it is necessary to scrape the surface of the steel or steel alloy to a certain thickness to remove these harmful foreign substances. This was solved by bottling it.

The thickness to be removed by this polishing is determined by the degree of dirt or foreign matter adhering to one surface and the thickness of the copper or steel alloy. The thickness of the steel or steel alloy surface is 10 times the thickness of the brad sheet metal body.
- If the degree is standard and therefore the crack vWIK is thin, the steel or steel alloy layer will also be thin and the thickness that can be chipped will also be limited.

If the thickness of the clad plate is 9.3 mm, the thickness of the pot or steel alloy is generally about 30J1, and even if it is scraped off by 1 degree, the inner stainless steel layer will not be exposed. It is impractical and impractical due to the high cost of shaving. Foreign matter such as stainless steel or nickel is attached to or has been implanted into the steel or steel alloy surface of the negative electrode container S.
It was confirmed that the depth was 3 to 5 μS degrees even at deep depths, and that it was possible to remove 6 seconds of scratches.

In this case, chemical polishing is suitable as a means for leveling the gap between the steels or steel alloys, since the thickness of the steel or steel alloy can be controlled relatively easily. Furthermore, the use of hydrogen peroxide and sulfuric acid-based chemical abrasives has the advantage that the thickness to be scraped can be precisely controlled by selecting the composition of hydrogen peroxide and sulfuric acid, treatment temperature, and time.

It takes time for the copper or copper alloy surface to remove foreign matter, and until then, hydrogen gas is generated from between the steel or steel alloy. Since the battery is assembled immediately after filling the negative electrode container with frozen zinc platter and alkaline electrolyte, the generation of hydrogen gas continues until after the battery is assembled. When hydrogen gas is generated inside the battery, it increases its impedance or increases the internal pressure (mj), causing leakage.

Therefore, in this generation lid, after cleaning the steel or copper alloy surface, this surface is amalgamated before battery assembly, and then filled with zinc chloride and alkaline electrolyte to prevent the generation of hydrogen gas. There is.

*a Containers generally have a shape with a folded part around the periphery by drawing processing, and when forming this folded part, the area around the folded part has to be drawn because the copper or steel alloy is highly processed. It has been stretched out and is thinner than the other parts. Therefore, if this part is scraped with a chemical polishing solution, the stainless steel will be exposed, which may generate hydrogen gas.

However, in this invention, since chemical polishing is performed while avoiding the folded portion, consideration is given to hydrogen gas generation and fat stop in this respect as well.

Next, one embodiment of the present invention will be described with reference to the drawings.

As shown in Figure 1, a nickel 1. A three-layer clad plate made of stainless steel 2 and steel 3 is used and drawn to produce a negative electrode container 4.

A synthetic resin jig 6 is attached to the peripheral folded part 5 of the negative electrode container 4.
After the surface was covered with a chemical polishing solution containing about 10 moles of hydrogen peroxide and 0.45 moles of sulfuric acid, and the molar ratio of sulfuric acid to hydrogen peroxide was 0.045, it was treated at room temperature for 2 minutes. After that, wash with water and sulfuric acid.

The exposed surface of the steel 3 is chemically dammed by repeating water washing, neutralization, and water washing. The average thickness of the scraped steel surface is approximately 6μ.

Next, the jig 6 was removed from the weir and immersed in an acetic acidic mercuric chloride solution to amalgamate the steel surface, followed by washing with water and drying.

Using this negative container 4, the acid as shown in FIG.
9 is an ion-permeable separator; 10 is an electrolyte holding material made of a porous fibrous material impregnated with an alkaline electrolyte; 11 is frozen zinc as a negative electrode active material. 1
Reference numeral 2 denotes an insulating backing that insulates the gap between the positive electrode container 7 and the negative electrode container 4 and seals the gap therebetween, and the opening of the positive electrode container 1 is curved inward to fasten the backing.

In the figure, 13 is a ring.

For comparison with the batteries made in this manner (6) with various can treatment solution compositions, including the battery 0, the same negative electrode containers were assembled using the same negative electrode containers that had been washed with trichlene, washed with alkali 4 times, washed with water, and dried. A comparison was made with a conventional battery η in terms of leakage. In other words, Table 1 is.

These batteries were stored in a test tank at a temperature of 6011: and a humidity of 901, and the number of leaked cells for each 1000 cells was measured using a 10x microscope. The changes in height due to hydrogen gas generation, etc. of batteries stored for 3 months at 45T: @ 90- were investigated, and each of the 1000 test batteries swelled to Q, 5mm.
This shows the number of batteries that have increased in price.

According to Table 2, No. 19 in the margin below, in the case of the conventional product (G), the storage period is 20 days.
On the other hand, in the case of battery cause due to 1jHc, a small number of leaks start after 30 days of blade storage and rapidly increase as the number of days increases. Even if the number of leaks increases, the number of leaks is significantly smaller than that of the conventional product η.

In addition, according to Table 2, there are 8 to 10 moles of hydrogen peroxide, 25 to 0.6 moles of sulfuric acid, and sulfuric acid to hydrogen peroxide. It can be seen that especially refreshing test results are obtained when the solenoid ratio is between 0.08 and 0, which is included in the range of 0.08-(LO6).

As described above, according to the present invention, after cleaning the surface of steel or steel gold that comes into contact with the active material of the negative current collector with hydrogen peroxide and sulfuric acid based chemical polishing liquid, mercury ions are removed. It is possible to provide a method for producing an alkaline battery that generates less hydrogen gas and can prolong its life without leakage or rupture by amalgamating the liquid containing the alkaline liquid.

Note that the present invention is not limited to the above-mentioned embodiments, and can be implemented with various modifications without changing the gist.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of a manufacturing factory according to an embodiment of the invention; Fig. 2
The figure is a longitudinal cross-sectional view showing a mercury oxide battery obtained in the same example. 1... Nickel 2... Stainless steel 3
...Steel 4.-Negative electrode container 5...Peripheral folded part 6-@＾ 9--Separator 1G...Electrolyte holding material 11.-
Zinc chloride 12...Insulating backing! 3-・One body

Claims (1)

[Scope of Claims] (The surface of the steel or steel alloy in contact with the negative electrode active material of the negative electrode current collector is polished and cleaned with a chemical polishing solution based on hydrogen peroxide or sulfuric acid, and then polished with a solution containing mercury ions. A method for producing an alkaline battery, characterized by comprising a step of amalgamation. (2) A patent characterized in that the chemical polishing liquid contains 8 to 10 moles of hydrogen peroxide and sulfuric acid (LL!5 to α6 moles) Claim 1! [Method for manufacturing an alkaline battery according to the machine set forth in paragraph 1. (3) The chemical polishing liquid has a molar ratio of sulfuric acid to hydrogen peroxide in a range of 0.03 to 0.06. A method for manufacturing an alkaline battery according to claim 1.