JPH0640492B2 - Organic electrolyte battery - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to an organic electrolyte battery, and more particularly to improving its storage characteristics.

2. Description of the Related Art In many cases, an organic electrolyte battery uses lithium, which has a high energy density, as a negative electrode active material, and uses a nonaqueous solvent that does not react with the active material in which an electrolyte is dissolved to form a battery.

In such a battery system, when the battery is constructed, the water contained in the parts and the water that enters after the construction adversely affect the performance such as a change in battery voltage and an increase in internal impedance.

There are the following conventional methods for reducing water content.

(1) Use fully dehydrated constituent materials.

(2) Reduce the area of the sealing part or lengthen the moisture invasion route.

(3) Glass is used in advance for the insulating portion of the current collectors of the positive electrode and the negative electrode, a sealing portion is provided in the current collector portion, and laser sealing is performed.

Problems to be Solved by the Invention Of the above methods, (1) is indispensable for organic electrolysis batteries. (2) requires a lot of development time for determining the material and shape of the gasket and the tightening rate of the gasket in the coin type or button type battery.
In addition, it is impossible to sufficiently prevent invasion of water, and it is impossible to use an active material that reacts sensitively with a small amount of water.
Compared to the method (2), the method (3) can sufficiently prevent the intrusion of water, but the manufacturing process is complicated and the cost is high. Further, when the electrode has a large bulge, the strength of the hermetically sealed portion becomes a problem.

An object of the present invention is to provide an organic electrolyte battery having improved storage characteristics by chemically solving the above-mentioned problems of mechanical or structural sealing.

Means for Solving the Problem In order to solve this problem, the present invention is one in which a supporting electrolyte is dissolved in an organic solvent, and further cesium carbonate is dissolved.

Operation By using this organic electrolyte, it is possible to eliminate various adverse effects such as a change in battery voltage and an increase in internal impedance caused by water invading the battery, and a battery having good storage characteristics can be obtained. Furthermore, when the method (2) is used, the manufacturing process is simplified, and a cheaper and more reliable battery than the method (3) can be obtained.

Embodiments Embodiments of the present invention will be described below with reference to FIGS. 1 and 2.

FIG. 1 shows the structure of the battery used to carry out the present invention. In the figure, 1 is a stainless steel sealing plate, 2 is a negative electrode made of a lithium metal piece pressed onto 1, and 3 is a nickel-plated iron case.

4 is a positive electrode mixture, which is 45 weight percent copper oxide as an active material, 40 weight percent of chalcopyrite, 10 weight percent of carbon black as a conductive agent, and 5 fluororesin binder.
It is a mixture of weight percentages. 5 is a polypropylene separator, 6 is a polypropylene gasket,
7 is a stainless steel ring.

The electrolytic solution used was prepared by dissolving lithium perchlorate in a mixed solvent of equal volume of propylene glycol and 1,2-dimethoxyethane at a ratio of 1 mol / and calcium carbonate 0.1 mol /. If the amount of cesium carbonate added is less than 0.01 mol / min, the effective period will be short, and
If the amount is more than 3 mol / mol, the electrolyte is saturated and precipitates.
It may damage the separator.

This battery has a total height of 2.0 mm and a capacity of 50 mAh. In this example, a mixture of copper oxide and chalcopyrite was used as the positive electrode active material, but it can be applied to various types such as manganese dioxide, graphite fluoride, and molybdenum oxide, which are known as active materials for organic electrolyte batteries. . Although propylene carbonate and 1,2-dimethoxyethane were used as the organic solvent, they can be applied to any mixed organic solvent containing ether.

FIG. 2 shows the battery shown in FIG. 1 at a temperature of 60 ° C. and a relative humidity of 9
It shows changes in battery voltage and changes in internal impedance when stored under high temperature and high humidity of 0%.
In the figure, A is an organic solution in which a predetermined amount of cesium carbonate is dissolved, and B is an organic electrolytic solution of the same composition to which cesium carbonate is not added.

In addition, FIG. 3 shows the characteristics of these batteries immediately after production and when the batteries that had been stored for 60 days at 60 ° C. and 90% high temperature and high humidity were discharged at 20 ° C. with a resistance load of 51 KΩ. In the figure, (a) is a discharge curve immediately after the production, and is a discharge curve with and without addition of cesium carbonate. (B) and (c) were stored at 60 ° C. and 90%, (b) was added with cesium carbonate, and (c) was not added.

EFFECTS OF THE INVENTION As is clear from the above description, the battery of the present invention using the electrolytic solution in which cesium carbonate is further dissolved in the organic solvent in which the supporting electrolyte is dissolved is chemically treated with a small amount of water invading into the battery. Therefore, the storage characteristics are good, and the conventional method can be applied to the manufacturing process, which is inexpensive and the reliability can be improved.

[Brief description of drawings]

FIG. 1 is a half sectional view of a button type battery in an embodiment of the present invention, FIG. 2 is a diagram showing storage characteristics of the battery, and FIG. 3 is a diagram showing comparison of discharge characteristics. 2 ... Lithium, 4 ... Positive electrode mixture, 5 ... Separator.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kaoru Murakami 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Akikatsu Morita, 1006 Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd.

Claims (2)

[Claims] 1. An organic electrolytic solution battery using an alkali metal or an alkaline earth metal as a negative electrode active material, wherein cesium carbonate is dissolved in the organic electrolytic solution. 2. The organic electrolytic solution battery according to claim 1, wherein the added amount of cesium carbonate is 0.01 mol to 0.3 mol per 1 liter of the organic electrolytic solution.