JPH01320755A - Button alkaline battery - Google Patents

Abstract

PURPOSE:To make maintainability superior by using a liquid containing material which bound a marcerized pipe with synthetic fibers by means of PVA fibers having specific characteristics. CONSTITUTION:A negative electrode 1 is stored in an opening seal plate 2 doubling as a negative terminal. A liquid containing material 3 which maintains electrolyte, a separator 4 and a positive electrode case 5 are provided, and a positive electrode 6 mainly composed of silver oxide is arranged at the inner bottom part and is fixed there by a positive electrode ring 7, and the positive electrode case 5 doubles as a positive terminal, and further an opening seal packing 8 consisting of synthetic resin to insulate the positive electrode from the negative electrode is provided. The liquid containing material 3 is a mixed paper type liquid containing material which bound a marcerized pipe and synthetic fibers by means of polyvinyl alcohol(PVA) fibers easy to dissolve, and a liquid containing material which bound them using PVA fibers whose dissolution temperature in water is 79-90 deg.C as the PVA fibers easy to dissolve is used. Hereby, a one excellent in maintainability and capable of standing for long-term use can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to improvements in button-type alkaline batteries used as power sources for electronic desktop calculators, electronic watches, and the like.

Conventional technology Conventional liquid-containing materials for button-type alkaline batteries include two henomercerized pulps, synthetic fibers (hardly soluble PVA fibers coated with polyvinyl alcohol), and easily soluble PVA fibers (non-acetalized, soluble in water). Temperature 50℃~60℃
) has been commonly used.

Problems to be Solved by the Invention In recent years, with the development of electronic devices, the current consumption of these devices has been rapidly decreasing, and the lifespan of the batteries that power these electronic devices has been extended due to this reduction in current consumption. It has become necessary to ensure long-term reliability for up to five years. However, for batteries made using conventional liquid-containing materials, the 60°C storage test (60°C), which is one of the general evaluation methods for alkali button batteries.

It is generally said that storage for 2Q days is equivalent to one year at room temperature. ) at 60℃ for 60 days (3 years at room temperature)
Since then, ``E pressurization or post-storage discharge has caused problems with battery capacity loss, and reliability over a long period of time has been insufficiently ensured. Since the dissolution temperature of the easily soluble PVA fiber 3-7 in water is 50°C to 60°C, 6
When a battery is stored at a temperature of 0°C, the easily soluble PVA fibers gradually dissolve in the alkaline electrolyte, and the binding force between the fibers of the liquid-containing material decreases, causing the fibers to fall apart and prevent liquid retention. It is thought that this caused the discharge performance to deteriorate. It is also believed that impurities in the liquid-containing material were eluted as the liquid-containing material was dissolved, causing voltage deterioration.

The above phenomenon is a problem when stored at 60°C, but the general operating temperature range of alkaline button batteries is -10°C to 60°C.
℃, it is likely that similar problems will occur in general use.

An object of the present invention is to solve the above-mentioned conventional problems and provide a button-type alkaline battery that is reliable over a long period of time.

Means to Solve the Problem In order to solve this problem, the present invention uses easily soluble PVA, which is a component of a mixed paper-type liquid-containing material, in which mercerized pulp and synthetic fibers are bound together by easily soluble PVA fibers. The fibers used had a dissolution temperature of 70°C to 90°C in water.

A method of increasing the dissolution temperature of easily soluble PVA fibers in water is to heat dry PVA fibers in air to sequester the hydrophilic ○H groups of PVA, which are the constituent molecules of the fibers. etc.

Function: According to this configuration, the temperature range (-10°C to 60°C) in which button-type alkaline batteries are generally used, or 6'O
Even in accelerated tests at ℃, the liquid-containing material did not elute.
Therefore, problems such as voltage deterioration and capacity loss are solved,
This is a button-type alkaline battery that is reliable over a long period of time.

EXAMPLE An example of the present invention will be described below with reference to the drawings. 1st
The figure is a sectional view of one embodiment of the present invention (silver oxide battery 5R716SW, outer diameter 7.9 mn, height 1.6 mm).

In FIG. 1, 1 is a negative electrode, and 2 is a sealing plate that houses the negative electrode 1 and also serves as a negative electrode terminal. 3 is a liquid-containing container of the present invention that holds an electrolyte, 4 is a separator, and 5 is a positive electrode case, the inner bottom of which contains silver oxide 5.

A positive electrode 6 mainly composed of is fixedly arranged on a positive electrode ring 7, and the positive electrode case 6 also serves as a positive electrode terminal. 8 is a sealing packing for insulating the positive electrode and the negative electrode, and is made of synthetic resin.

Table 1 shows conventional liquid-containing materials (9 conditions in which the dissolution temperature of easily soluble PVA fibers in water is 60°C to 60°C) and the liquid-containing material of the present invention (9 conditions in which the dissolution temperature of easily soluble PVA fibers in water is 60°C to 60°C). temperature is 70℃
The open circuit voltage and battery capacity were compared when 5R71esW was manufactured using 9 conditions (1) to 90°C and a 60°C storage test was performed. Each numerical value in the table is an average value of 20 pieces of data, and the numerical value in parentheses indicates its standard deviation.

6 page 7 ts p As is clear from Table 1, in the case of condition I (conventional example), 6
It can be seen that by storing the battery at 0°C for 60 days or more, the open circuit voltage of the battery decreases and the capacity drops. However, in the case of condition ① (the present invention), 60°C
Even after storage for 100 days, there was no drop in open circuit voltage or loss of capacity of the battery, and it can be said that the battery is reliable and can be used for a long period of time. The above results are considered to be due to the difference in the dissolution temperature in water of the easily soluble PVA fibers in the mixed paper.

In the present invention, the dissolution temperature of easily soluble PVA fibers in water is set to 70°C to 90°C, but this is because the above-mentioned problems are likely to occur at temperatures below 70°C. Upper limit to 90℃
This is because when easily soluble PVA fibers with a dissolution temperature in water of 90°C or higher are used, many of the hydrophilic ○H groups are blocked, resulting in poor dispersibility in water during paper making. However, if a battery is made using such a liquid-containing material, for example, if the component ratio of the mercerized pulp decreases slightly, the liquid retention properties will deteriorate. This is because there was a problem that variations occurred in the internal resistance of the battery.

The component ratios of the soaked liquid used in the present invention are: mercerized pulp: 50 to 65 parts by weight, 1 part by weight of synthetic fibers, 30 to 40 parts by weight of easily soluble PVA fibers, 5 to 0 parts by weight of easily soluble PVA fibers, and 5 to 0 parts by weight of easily soluble PVA fibers. Experiments have confirmed that this method is effective in bringing out the alkali resistance of synthetic fibers and the binding strength of easily soluble PVA fibers.

In this example, a button-type alkaline battery whose positive electrode active material is 5R716SW whose main component is silver oxide is used as an example, but other button-type alkaline batteries whose positive electrode active material is mercury oxide or manganese dioxide as a main component are used. Similar results can be obtained with .

Effects of the Invention As is clear from the above explanation, the present invention uses a liquid-containing material in which mercerized pulp and synthetic fibers are bonded with easily soluble PVA fibers whose dissolution temperature in water is 70°C to 90°C. The battery has good storage performance and can withstand long-term use.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a button-type alkaline battery according to an embodiment of the present invention. 1--Negative electrode, 2--Sealing plate, 3--Liquid impregnation, 4--Separator, 5--Positive electrode case, 6-- Positive electrode, 7... Positive electrode ring, 8
...Soking. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure I-jj, taken? -Muraguchi board 3-... Including Koshuttle 4-° and pallet 5- Correct case 6---Positive plate 7- Positive link 8-II + Packing

Claims (1)

[Claims] A battery comprising a positive electrode, a negative electrode, an alkaline electrolyte, a liquid-containing material that holds the alkaline electrolyte between the positive and negative electrodes, and a separator, the liquid-containing material comprising a mercerized pipe and synthetic fibers. A mixed paper-type liquid-containing material made by binding together with easily soluble polyvinyl alcohol fibers (PVA fibers),
A button-shaped alkaline battery characterized in that the easily soluble PVA fiber has a dissolution temperature in water of 70°C to 90°C.