JPS6041760A - Mercury battery - Google Patents

Abstract

PURPOSE:To provide a mercury battery having steady static performance and discharge capacity by adding a specivied amount of cadmium oxide to a positive mix containing mercuric oxide as main positive active material. CONSTITUTION:1-8pts.wt. cadmium oxide is added to 100pts.wt. mercuric oxide in a positive mix using mercuric oxide as main positive active material. For example, a positive mix 2 is formed in such a manner that 5pts.wt. graphite or acetylene black and 1-5pts.wt. cadmium oxide are mixed to 100pts.wt. mercuric oxide, and the mixture is formed in a form of pellet, then the pellet is pressed in a positive case with a positive ring 3. Since the positive mix containing cadmium oxide is easy to form a pellet, the pellet has uniform density and steady electrolyte absorption amount, and electrolyte penetrates uniformly into the pellet. Since cadmium oxide is converted to cadmium hydroxide by electrolyte, electrolyte penetrates to fine pores of the mix. Therefore, discharge capacity and static performance of a battery are stabilized.

Description

[Detailed description of the invention] Industrial applications The present invention relates to improvements in positive electrodes for mercury batteries.

Conventional configuration and its problems Mercury batteries have little voltage change during discharge, excellent storage performance, are small, and have a large electric capacity per double volume. In addition, since the open circuit voltage is stable over a long period of time, it can be used as a power source for small electronic devices such as hearing aids, exposed parts of cameras, open side 2, and wristwatches.

It has been used for a long time in transceivers, pagers, etc.

In recent years, as devices have become smaller, there has been a demand for smaller batteries. As a result, stabilization of the discharge capacity and static characteristics of batteries has become a problem.

A positive electrode 'f of a conventional mercury battery is shown in FIG. In the figure, 1 is a metal case that also serves as a positive electrode terminal, and 2 is a positive electrode mixture consisting of iE electrode active materials mercury oxide and manganese dioxide, conductive agents graphite or acetylene black, and calcined manganese. It is press-molded into a case together with the positive electrode ring 3.

In the above configuration, there is a disadvantage that the mixture density in the lower part 2a of the positive electrode ring becomes high, and penetration of the electrolyte becomes poor. It's ox-J
2+4 (With the 2 mixture composition, the moldability of the mixture is slightly stable and the mixture density is uneven, so the permeation rate of the electrolyte is slow,
The amount of liquid absorbed is not stable. As a result, the discharge capacity of the battery,
Static characteristics become unstable.

OBJECTS OF THE INVENTION The present invention eliminates the above-mentioned drawbacks and
I4:, .

Our objective is to provide a mercury battery with stable discharge capacity.

Structure of the Invention The present invention is a positive electrode mixture containing mercury oxide as the main positive electrode active material, in which 1 to 8 layers of cadmium oxide is impregnated by 7 J to 100 layers of mercury oxide. .

According to this configuration, the molding of the mixture r]-7 is good and the density of the molded mixture becomes uniform. It is extremely effective against scratches.
(Since the density of the mixture 2a does not become so high that it absorbs the electrolyte, it is quickly and evenly absorbed into the positive electrode mixture,
The amount of liquid absorbed is also stable. Moreover, depending on the IE positive electrode mixture, there is an effect that the electrolyte liquid further penetrates into the IE cathode mixture. As a result, the suspension and static characteristics become stable.

Furthermore, since cadmium oxide removes hydrogen gas generated from the negative electrode side, it also has the advantage of preventing equipment damage due to battery expansion/molten rupture.

Description of examples FIG. 2 shows a mercury cell MR9 according to an embodiment of the invention.

In the figure, 1 is a steel plate with a thickness of 0.30 mm, the outer diameter of the lower part of the stepped part is 13.1 mrn, and the lower part of the stepped part gB is 2.60 mm.
r Stepped part lower part outer diameter 15.6 mm, height 6.80
Punch out 1J to mm, and cloth 7
This is the F4 case. In a 2-piece positive electrode mixture, 100 parts by weight of mercury oxide as an active material, 5 parts by weight of graphite or acetylene plaque as a conductive material, and 1 to 5 parts by weight of cadmium oxide were mixed, and the mixture was made into pellets. After forming into
It is press-molded into the IE electrode case together with the positive electrode ring 3. 41j is a separator made of polyethylene, polypropylene, etc.; 6 Phantom-negative electrode mixture, from a kneading product of zinc hydrate powder with a concentration of 5 to 15 and electrolytic M' (liquid potassium hydroxide aqueous solution, thickeners such as sodium polyacrylate and carbogine methylcellulose). 7 is] 1 no, 0.40 +rtyn nickel-stainless steel-
A three-layer steel clad shrine with an outer diameter of 13.80 mm and a height of 2
．． Sealing plate processed to 60mm, 8C polyamide resin,
Polyethylene I/resin, polyglopylene 4fg Ile
Etc. J: Rinaru insulating gas gasket, ), and this gasket)
・The above-mentioned negative electrode is filled in the assembly seal 1'' plate 7 with 8 attached.
It will be done.

Since the positive electrode mixture containing cadmium oxide has poor moldability, the density of the mixture becomes uniform when it is pressure-molded.
The amount of electrolyte absorbed is stabilized, and the electrolyte permeates uniformly into the mixture. In addition, cadmium oxide changes to cadmium hydroxide in the electrolyte solution, resulting in a mixture of +1
The electric Jqq liquid penetrates into the i111 part. As a result, the discharge capacity and static characteristics of the battery are stabilized.

FIG. 3 shows the relationship between the variation in battery internal resistance and the average value for batteries in which the content of cadmium oxide in the positive electrode mixture was changed. Note that the number of samples was 20 for each. When the content of cadmium oxide is 1 to 8 parts by weight per 100 parts by weight of mercury oxide, the internal resistance becomes stable and the variation becomes small.

Fig. 4 shows the relationship between the dispersion of the discharge g-solution and the average value for the cadmium oxide intercalation [-9U].

From this figure, it is clear that when 1 to 8 parts by weight of cadmium oxide is contained per 100 parts of mercury oxide, the discharge capacity becomes stable and the variation becomes small.

Next, a battery using a positive electrode mixture containing 3 molded portions of cadmium oxide with respect to 100 parts by weight of mercury oxide is designated A1, a battery using a positive electrode mixture containing no cadmium oxide is designated B, and the internal resistance, A comparison of the standard deviations of discharge capacity is shown in the following table. There are 201,161 samples each.

It is clear from the implementation of the invention that exceeds the effects of the invention.According to the present invention, a mercury battery that is both accommodating and statically stable can be obtained.

4. Simplification of the drawings Figure 1 is a vertical cross-section 18'' showing the state in which the positive electrode case is filled with the positive electrode mixture according to the conventional configuration, Figure 2 - Kinoi 1, 1l-1
Example (a side view of a part of the battery in section V, with the cross section V cut out; Figure 3 shows the change in internal resistance when the content of cadmium oxide in the mixture is changed to 1); 54 is a diagram showing the transition of discharge capacity when the content ratio of cadmium oxide is changed.

1...Positive case, 2-Positive electrode mixture, 4 Separator, 5...Liquid-containing material, 6...-Negative electrode, 7- Seal 1
” Board, 8... Insulation power socket.

Agent's name Benmu]! Toshio Nakao and 1 other car 1 1] Figure 2 Figure 3 Part Resistance lO: ■

Claims (1)

[Claims] A mercury battery characterized in that a positive electrode mixture containing mercury oxide as a main positive electrode active material contains 1 to 8 parts by weight of cadmium oxide in addition to 100 parts by weight of mercury oxide.