JPH0636364B2 - Non-aqueous electrolyte battery - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application The present invention provides a non-aqueous electrolyte comprising a negative electrode using lithium or a lithium compound as an active material, a non-aqueous electrolyte, and a positive electrode using cupric oxide as an active material. A water electrolyte battery.

B. Conventional Technique A non-aqueous electrolyte battery using a negative electrode containing lithium or a lithium compound as an active material has the advantages of high energy density and low self-discharge. And, for example, Japanese Patent Publication Sho 5
As disclosed in JP-A-6-40471, when cupric oxide is combined as a positive electrode active material, the battery voltage becomes about 1.5 V, which is advantageous in that it can be used interchangeably with existing alkaline dry batteries, mercury batteries, silver batteries and the like. is there.

C. Problems to be Solved by the Invention In conventional lithium cupric monoxide-based non-aqueous electrolyte batteries, powdery cupric oxide was used. However, the cupric oxide powder has a small surface area, and the positive electrode formed from this powder has a small porosity, so that the liquid content is low, and as a result, there is a problem that the internal resistance increases with storage.

D. Means for Solving the Problems The present invention is characterized by using fibrous cupric oxide as the positive electrode active material.

E. The surface area of powdered cupric oxide used is less than 1 m ² / g, while that of fibrous cupric oxide is extremely large, about 5 m ² / g. Therefore, the porosity of the positive electrode molded of fibrous cupric oxide is large and the liquid content is high, so that the amount of the electrolytic solution in the positive electrode is increased and lithium ions, which are the negative electrode active material, easily diffuse and the internal resistance is felt. it can.

Further, by using fibrous cupric oxide as an active material, expansion of the positive electrode during discharge can be suppressed. That is, the cause of the positive electrode expansion is that the metallic copper produced by the discharge reaction is an ultrafine powder and becomes bulky. When fibrous cupric oxide is used, the porosity of electricity is large as described above, and if filled, the voids in the electrode become large, so the bulkiness of metallic copper can be absorbed by this void portion. As a result, expansion of the positive electrode itself can be suppressed.

F. Examples Examples of the present invention will be described in detail below.

To 85% by weight of fibrous cupric oxide having a fiber diameter of about 1 to 10 μm, 10% by weight of graphite as a conductive agent and 5% by weight of fluororesin powder as a binder were added and mixed.
Pressure molding is performed at a pressure of ton / cm ² to obtain a molded body having a diameter of 15.0 mm and a thickness of 1.1 mm, and this molded body is at 200 to 300 ° C.
Heat treatment is carried out at a temperature of to obtain a positive electrode.

The negative electrode is obtained by rolling a rolled lithium plate to a thickness of about 0.6 mm and punching the rolled lithium plate to a diameter of 15.0 mm. The electrolyte is 1 mol / liter of lithium perchlorate in a mixed solvent of propylene carbonate and 1.2-dimethoxyethane.
A battery (A) of the present invention having a diameter of 20.0 mm and a thickness of 2.5 mm was prepared using the melted product and a polypropyne nonwoven fabric as a separator.

On the other hand, for comparison, a conventional battery (B) similar to the battery of the present invention was prepared except that a commercially available special grade cupric oxide powder was used as the positive electrode active material.

Fig. 1 shows the changes in internal resistance over time when these batteries were stored under the conditions of a temperature of 60 ° C and a humidity of 90%, and Fig. 2 shows that after the batteries were assembled, they were stored at 60 ° C for 3 months and then at 20 ° C. 1K
Shows discharge characteristics under Ω load.

It can be seen from FIGS. 1 and 2 that the battery (A) of the present invention has improved storage characteristics as compared with the conventional battery (B).

As described above, when the positive electrode using fibrous cupric oxide as the active material is used, the porosity is large and the liquid content is high, so that the amount of the electrolytic solution in the positive electrode is increased and the liquid accompanying storage is increased. It is possible to suppress an increase in internal resistance due to insufficient amount and improve the storage characteristics of the battery.

Also, since the porosity is large, the bulkiness due to the change from cupric oxide to metallic copper due to the discharge reaction can be absorbed in the voids of the porous part and the expansion of the positive electrode itself can be suppressed. Can be suppressed.

[Brief description of drawings]

1 and 2 are characteristic comparison diagrams of the battery of the present invention and a conventional battery. FIG. 1 shows changes in internal resistance with time at high temperature and high humidity, and FIG. 2 shows results after storage at high temperature. The discharge characteristics are shown respectively. (A) ... Battery of the present invention, (B) ... Conventional battery.

Claims (1)

[Claims] 1. A non-aqueous electrolyte battery comprising a negative electrode containing lithium or a lithium compound as an active material, a non-aqueous electrolyte solution, and a positive electrode containing fibrous cupric oxide as an active material.