JPS5882466A - Siliver oxide battery - Google Patents

Abstract

PURPOSE:To improve storage performance of a battery and prevent internal shortcut at the time of discharge by torcing a porous synthetic resin film having a power of stopping the transmission of a zinc acid ion and a silver acid ion into a separator layer to closely make contact with the positive pole black mix. CONSTITUTION:A porous synthetic resin film 5 has the constitution, wherein holes of a porous substance are filled with powder of calcium hydroxide while being bound by the synthetic resin, the material of which only need to be alkaline-proof and especially polyetylene, polysulphone, polyamide, polypropylene and polyethylene are used while being placed to closely make contact with the negative pole black mix 6. Further the average hole diameter applied to the porous synthetic resin film of the separator layer A need to be properly sized for checking an increase of electric resistance being produced for not reducing the frequency of collisions of calcium hydroxide with ions and for making plenty of powder of calcium hydroxide to be contained in the film.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a silver oxide battery that has improved storage performance and prevents internal short circuits during discharge.

Conventionally, a non-woven fabric made of synthetic resin or a microporous synthetic resin membrane has been used for some sheets used in the seven-palate group of #1 silver ide batteries. In the former case, zincate ions eluted from the cathode side or silverate ions eluted from the anode side are deposited on the anode or cathode, forming a nonwoven fabric! ) It had the disadvantage that it grows inside the IJ box and reaches the anode or cathode side, resulting in slight shortening and circuits.

Since the latter is a microporous membrane with a more complex structure than nonwoven fabric, it takes longer for zinc or silver to precipitate on the anode or cathode side, grow, and form a slight short circuit with the anode or cathode side. Although this is an improvement over the former, it ends up causing a slight short circuit over time. As a further improvement.

Among the latter microporous synthetic resin membranes, membranes containing titanium oxide to have a moldy structure may also be used. In this case, it has been found that short circuits due to the growth of precipitated zinc are more suppressed, but conversely short circuits due to the growth of precipitated silver become more likely to occur. The reason for this latter phenomenon is that the cellophane chains arranged on the anode side of the separator group prevent the silver acid ions eluted from the anode side from being reduced to metallic silver and captured.

In other words, metallic silver that is eluted as potassium titanate in the solution and reduced and precipitated on cellophane is re-eluted as silver titanate, which makes it difficult for silver to be captured by potassium titanate, and the silver is transferred to the cathode side. This has the disadvantage that the arrival of silver and the accompanying growth of silver on the cathode are promoted, and a slight short circuit with the anode is likely to occur.

The present invention eliminates the above-mentioned drawbacks.

This will be explained in detail below using examples. Figures 1 and 2 show a cross-sectional view of a silver oxide button sound cell. 1 is an anode mixture made by mixing and molding silver oxide and graphite, which is crimped and packed into a coffin can 2 made of a single nickel-plated plate. are doing. 3. The membrane is the Pareta layer, and the membrane is permeable. Sehan membrane 41 is composed of the porous synthetic resin membrane 5 of the present invention. 6 is a cathode mixture made of paste-type zinc powder, 7 is 1iNi [The surface in contact with the cathode mixture 6 is copper plated, the outer surface is made of a nickel layer, The periphery is made of polyethylene.

The contents of the firefly are completely sealed by bending the upper part of the anode can 2 inward through a gasket 8 made of an alkali-resistant insulator such as knife.

The porous synthetic resin membrane 5 used in the present invention has a structure in which the pores of a porous body are filled with calcium hydroxide powder and are bound together by a synthetic resin.

The material only needs to be alkali resistant.
In particular, styrene, polysulfone, polyamide, polypropylene, polyethylene, etc. are used, and the device is arranged so as to be in contact with the cathode mixture 6.

Example 1 = In the silver oxide button source battery having the structure described above, the porous component T & resin M5 was prepared by dissolving 8 parts by weight of polystyrene in 68 parts by weight of tetrahydrofuran, and adding 24 parts by weight of isopropyl alcohol to dissolve it uniformly. Thereafter, 55 parts by weight of calcium hydroxide having an average particle size of 4 μm are added to the solution and mixed uniformly. The above mixed solution was impregnated and coated on a vinyl non-woven fabric (e.g. thick O, OSM), and the temperature was 6.
Dry at 0° C. and 70% humidity to obtain 3 sheets with a thickness of 0.07111 mm. The electrical resistance of this sheet was measured in a 25% potassium hydroxide solution at 25°C.
It was mQ-cd/disc. Furthermore, the average pore diameter measured by mercury cross-cutting was 2 microns.

Example 1: The porous synthetic resin membrane 5 in this example was prepared by dissolving 8 parts by weight of polystyrene in 68 parts by weight of tetrahydrofuran, adding 15 parts by weight of isobrivyl alcohol, and uniformly dissolving the solution. 53 parts by weight of calcium hydroxide having an average particle size of 1 μm were added to the mixture and mixed uniformly. A sheet with a thickness of 0.07 fin was produced using the above mixed liquid in the same manner as in Example I. was 100 sea bream Ω·cd/maki, and the average pore diameter was 0.4 μm.

Example I: A mixed solution prepared by adding calcium hydroxide having an average particle size of 20μ by changing the particle size of calcium hydroxide to the solution shown in Example A sheet with a thickness of 0.071111 was manufactured. The electrical resistance of this sheet was 82 Ω·ctd/sheet, and the average pore diameter was 12 μm.

Example 1 above. In comparison to IL'1, the following two-sided sheet was used in place of the porous synthetic resin membrane 5 of the separator layer of a silver oxide button cell with the above-described structure in a comparative example.

Comparative Example 1.1 consists of one without adding calcium hydroxide (1) shown in Example I and one with 'Cr instead of calcium hydroxide.
One ton of Ik titanium was added to each part of the titanium to form a sheet with a thickness of 0.07 fi. Comparative example! The sheet of Comparative Example 1 had an electric resistance of 78 Ω·cd/sheet and an average pore diameter of 2.5 μm, and the sheet of Comparative Example 1 had an electrical resistance of 82 Ω·cd/sheet and an average pore diameter of 1.7 μm.

In addition, a silver oxide button type battery was also fabricated in which the porous synthetic resin membrane 5 was replaced with a vinyl cotton cloth. In addition, the palate layer is a milliethylene film 5.0 to which acrylic acid is grafted from the positive side. Shichisuhan membrane 4. It has a five-layer structure in which the above-mentioned □ sheets are arranged.

In the battery capacity test, the capacity was determined to a final voltage of 1.4 V when the battery was discharged at 11 degrees and 24 degrees Celsius with a load resistance of 30 Ω. In addition, in order to confirm the change in capacity after being left unused, it was left unused for 100 days at a temperature of 60°C and a humidity of 90°C.

The capacity test described above was conducted. The results are shown in the table below.

Navy blue* In the case of vinylon nonwoven fabric, the capacity immediately after manufacturing is assumed to be 100%.

As shown in the above results, the battery of the present invention was superior to the conventional battery in that the battery capacity decreased less after being left unused.

As mentioned above, the average pore diameter used for the porous synthetic resin group of the hepeptalate layer is determined in order not to reduce the frequency of collisions between calcium hydroxide and ions, and to prevent a large amount of calcium hydroxide from being contained in the powder T-film. In order to prevent an increase in electrical resistance caused by the inclusion of the oxide, it is necessary to make the size .

To this end, membranes with various average pore sizes were fabricated by increasing the styrene concentration, decreasing isoptabil alcohol, or decreasing or increasing the particle size of calcium hydroxide in the same manner as in the examples, and their electrical resistance Figure 5 shows the leakage results. Furthermore, the relationship between the storage performance and the average pore diameter of the membrane is shown in FIG. As shown in No. 58.

Where the average pore diameter is smaller than around 0.01 μm.

There is a large increase in electrical resistance, and by making the battery performance more variable, stable electrical resistance can be obtained, especially at 0.5μ
- 0 or higher is good; on the other hand, as shown in Figure 14, 100
If it exceeds 1 μm, the storage performance will decrease rapidly.
It is necessary to use sea bream up to 00μ in size, and particularly stable up to 5μ in size. From these points, if the porous synthetic resin membrane in contact with the cathode mixture in the separator layer used in the present invention has an average pore size in the range of 0.01μ to 100μ, it will be stable and shelf-stable. In order to obtain a good battery and particularly stable performance, a material with an average pore diameter of 0.5 to 5 μm may be used.

As described above, the present invention improves the storage performance of the battery by bringing a porous synthetic resin group having the permeation blocking ability of zincate ions and silverate ions into contact with the anode mixture in the heptaparator layer. It can prevent internal short circuits during operation, and its industrial value is great.

[Brief explanation of the drawing]

Fig. 1 FIA, Fig. 2 is a cross-sectional view of a silver oxide battery according to the present invention and a partially enlarged cross-sectional view of the seven palator layers, Fig. 5 is an average pore diameter-electrical resistance characteristic diagram, and Fig. 4 & average pore diameter-storage performance characteristic diagram. be. 1... Anode mixture, 5... Porous synthetic resin group. 6...Cathode mixture, Mu...Separator layer. Applicant Yuasa Battery Co., Ltd. Figure 1 Figure 2 Agony

Claims (1)

[Claims] The sheet in contact with the unipolar mixture in the seven pallet layers arranged between the positive electrode mixture mainly composed of acids (t and m) and the negative electrode mixture mainly composed of zinc contained calcium hydroxide. Porous synthetic resin with an average pore diameter in the range of 0.01 to 100μ
A silver oxide battery using a membrane.