JPS6031069B2 - silver peroxide battery - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a silver peroxide battery with excellent stability, and more particularly to an improved silver peroxide battery that does not lose stability even when potassium hydroxide is used as the battery electrolyte. .

Conventional alkaline batteries have been known to use an active material based on silver peroxide for the anode and zinc, etc. for the cathode, but silver peroxide has a lower oxygen content than other oxides such as silver oxide. Since the content is large, the discharge performance of batteries using this material is significantly improved.

However, silver peroxide has low stability within the battery and gradually decomposes into silver oxide and oxygen, so the oxygen generated during storage of the battery increases the internal pressure of the battery, causing the battery to expand and deform, or become severely deformed. Sometimes it can be destroyed. The major cause of these drawbacks of peroxide wire batteries is thought to be the reaction with the alkaline electrolyte that comes into contact with them.

In order to eliminate this drawback, coating the surface of silver peroxide particles with silver lead acid is described in US Pat. No. 3,017,448, and the storage performance of the battery is improved. Silver peroxide batteries generally use sodium hydroxide as the electrolyte, but for applications that require a large amount of water at once, it is necessary to use potassium hydroxide as the electrolyte. The commonly obtained filtered silver oxide is less stable in potassium hydroxide electrolytes than in sodium hydroxide electrolytes. Therefore, there is a need to develop a silver peroxide battery in which the electrolyte has excellent stability similar to that of sodium hydroxide and generates less gas. On the other hand, the inventors have conducted various studies on a method for producing stable silver peroxide, and have already filed a patent application for an improved method for producing silver peroxide in which silver nitrate is oxidized with an oxidizing agent in a commonly used alkaline hydroxide solution. 52-150591, Japanese Patent Application No. 53-120992, and Japanese Patent Application No. 53-153689.

These are a method of adding the required amount of silver nitrate and an oxidizing agent to excess alkali hydroxide and adding it in several parts at slight intervals, and a method of adding silver nitrate to an alkali hydroxide to obtain silver oxide Ag20. After a sufficient period of time for crystal growth, an oxidizing agent is added to produce silver peroxide, and an alkali hydroxide is added to silver nitrate to obtain silver oxide Ag20, after a period of time for crystal growth in the same manner as described above. , a method of producing silver peroxide by adding an oxidizing agent, both of which are extremely stable and have a low gas generation rate measured using an aqueous sodium hydroxide solution compared to conventional general production methods. Obtained. In addition, the inventors added silver nitrate to alkali hydroxide to obtain silver oxide, and after allowing the crystals to grow sufficiently, added an oxidizing agent and coated the surface of the obtained silver peroxide with lead salt or the like. He discovered that a product with even better stability could be obtained by using the method, and proposed Samurai Gan No. 35-145914, and Tokuto No. 10312-1970, which coated the surface of silver peroxide with both lead and tellurium. proposed a method. As a result of various studies on stabilizing silver peroxide batteries, the inventors discovered that instead of adding various additives to the produced silver peroxide in order to stabilize the silver peroxide used as the active material for the intestinal electrode, The present invention was developed based on the fact that adding additives to an alkaline electrolyte has profound effects. The object of the present invention is to provide a silver peroxide battery with excellent stability, especially a peroxide battery that does not lose stability even when using potassium hydroxide as an alkaline electrolyte. In order to achieve the object, the present invention constructs a silver peroxide battery by incorporating lead and aluminum into the alkaline electrolyte of the silver peroxide battery.

According to the present invention, it is effective to improve the stability of silver peroxide batteries by using silver peroxide produced by a conventionally known production method as an active material for the intestinal electrode, but the present invention is effective in improving the stability of silver peroxide batteries.
2-150591, Samurai Kao Sho $-20992, and Japanese Patent Application No. 153-153, etc., silver peroxide produced by a method that controls the addition order, time, etc. of the agent for silver peroxide production, etc. When used as an anode active material, it is effective in further improving stability.

Further, even if the filtered silver oxide, which is the anode host material used in the silver peroxide battery of the present invention, contains an additive substance for suppressing gas generation, the present invention will not be prevented. Even when the alkaline electrolyte used in a silver peroxide battery is sodium hydroxide, applying the present invention is effective in improving stability, but the effect is remarkable when the electrolyte is potassium hydroxide.

For the lead contained in the alkaline electrolyte, in addition to metallic lead powder, alkali-soluble oxides such as lead monoxide can be used, and for aluminum, in addition to metallic aluminum powder, alkali-soluble aluminum such as aluminum hydroxide can be used. A salt is formed, and the amount added is not particularly limited, but the weight ratio of Pb and A is 0.1 to 20, and the total concentration of both components is 15.
It is preferable that the amount is less than 100 ml, and if it is added more than this, the alkalinity of the alkaline electrolyte will decrease and the practical effect will be poor.

Reference examples and examples will be described below. Reference Example Regarding the stability of silver peroxide produced by a method known to date, and of silver peroxide produced according to a method proposed and filed by the inventors, without adding any additives to the alkaline solution, in 40% NaOH aqueous solution or K
Table 1 shows the results of measuring the gas generation rate per 40q○ of the product per night in an OH aqueous solution.

Table 1 The outline of the manufacturing method for each brand of Ago in Table 1 is as follows.

A: According to a conventionally known method, 72 mm of NaOH was dissolved in 1 mm of water and heated to 8 mm, Kub20875 was mixed and added to 0.2 mm of water, and then AgN0351 was dissolved in 50 mm of water. The mixture was dissolved in water, heated to 90°C, heated to 90°C for 18 minutes, and dried in a washing oven.

B: According to the manufacturing method related to Tsubakimaya Showa No. 52-150591, 48 parts of NaOH was dissolved in 1 part of water, heated to 85 parts, and 1/2 amount of K2S20875 parts mixed on 2 parts of water was added. Immediately, A added 1'2 base of a solution of 0351 dissolved in 50 ml of water and stirred for 1 minute, then added the remaining amount of uniform S208 and the remaining amount of A 03 solution and heated at 90°C for 10 minutes. After lighting, it was washed and dried in a furnace.

C: Hakama Isoaki 53-153 total match According to this manufacturing method, KOH16 was dissolved in 350 parts of water and heated to 80°C, and a solution of AgNQ51 dissolved in 50 parts of water was added. At 80 o'clock, stir the rope for 1 time, then add KOH 53 Yu and stir for 10 minutes, then add KOH 20852 Yu mixed with 15 parts of water and heat at 90℃ for 25 minutes. did.

The results in Table 1' show that when no stabilizing substance is added to the alkaline solution, the gas generation amount increases in the measured values in the potassium hydroxide aqueous solution compared to the values in the sodium hydroxide aqueous solution, and the anode becomes active. It has been shown that silver peroxide as a substance is particularly unstable in potassium hydroxide solution.

Example 1 An electrolytic solution of 4% by weight or 5% by weight was prepared by dissolving lead monoxide as the lead component and metallic aluminum as the aluminum component in a potassium hydroxide aqueous solution of 4% by weight. Table 2 shows the results of determining the amount of gas produced in 4 hours, 1q hours, and 48q hours per evening for each brand of silver peroxide product.

The tests in Table 2 5000 were performed in comparison to 4000 to clearly show the differences in sample stability.

Test M. No. 1 has no stabilizer added in the KOH solution. Test No. Nos. 4 to 10 are those obtained by dissolving Pb and Ag in the alkaline electrolyte of the present invention, and containing no additives of N.
o. It is recognized that the amount of gas generated is significantly reduced compared to Test No. 1. 11 and 12 have lead content)
Because it is too much, it does not show good results except for long-term performance. Example 2 The electrolyte of a normal silver peroxide battery is an alkaline aqueous solution containing Zn.
Although Zn○ is contained in a nearly saturated state, we tested what kind of influence this Zn○ has.

Zn011 is further added to the 40% by weight potassium hydroxide aqueous solution.
Using an electrolyte containing A and Pb by dissolving aluminum powder and lead monoxide for 4 nights/day and containing A and Pb each for 48 hours and 100 hours, brand C Mikuni Oxide Silver was used at 5,000 yen per night. Table 3 shows the results of determining the amount of gas generated.

Table 3 Test vessel. No. 13 contains no ZN○, Pb, or A as an electrolyte, and the test port. When Zn○ is contained as in test M. No. 15 was obtained by further containing Pb and Al as the electrolytic solution of the present invention in Zn0, and it was observed that the amount of gas generated was reduced by Zn.

Example 3 Results of calculating the amount of gas generated in 4 anchor hours and log time per evening of silver peroxide for brands A and C by adding lead and aluminum to a 40% by weight aqueous sodium hydroxide solution or potassium hydroxide aqueous solution at 50q0 are shown in Table 4.

Table 4 The results in Table 4 show that even if Ago is manufactured using brand A according to the conventionally known method, or brand C is used according to an improved manufacturing method, Pb remains in the alkali solution. It is recognized that when A and A were added, the amount of gas generated was significantly reduced compared to when no additive was added.

Claims (1)

[Claims] 1. A silver peroxide battery in which an anode is formed using silver peroxide as a main ingredient, and the alkaline electrolyte contains lead and aluminum.