JPS61107662A - Nonaqueous electrolyte battery - Google Patents

Abstract

PURPOSE:To improve storage life and voltage of a battery by adding molybdenum trisulfide and iron disulfide to positive electrode using cupric oxide as active material. CONSTITUTION:80wt% cupric oxide, 5wt% molybdenum trisulfide and 15wt% iron disulfide are mixed to prepare a positive mix. 85wt% positive mix, 10wt% the mixture of acetylene black and graphite and 5wt% fluorine resin powder which serves as a binder are mixed and pressed to mold a pellet measuring 15.0mm diameter and 1.1mm thickness. The pellet is heated to obtain a positive electrode 1. An about 0.6mm thick lithium sheet is punched in a 15.0mm diameter disk to form a negative electrode 2. Thereby, since deposit of metallic copper on the surface of lithium negative electrode is suppressed, increase in internal resistance is suppressed and storage life is increased and voltage is increased.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a non-aqueous electrolyte battery using cupric oxide as a positive electrode active material.

Conventional technology A non-aqueous electrolyte battery using cupric oxide as a positive electrode active material and lithium or a lithium alloy as a negative electrode active material was developed, for example, by
913935, the battery voltage is approximately 1
．． Since it is about 4V, it has the advantage that it can be used interchangeably with silver oxide batteries and mercury batteries that are commonly used as power sources for electronic devices.

However, when this type of battery is stored, the cupric oxide as the positive electrode active material decomposes, metallic copper dissolves in the electrolyte, and this metallic steel precipitates on the surface of the lithium negative electrode, increasing the internal resistance.
There is a problem that the discharge capacity of the battery decreases, and although it is compatible with 1.5V batteries such as silver oxide batteries and mercury batteries, the voltage is somewhat low, so it is desired to improve the voltage.

e→ Problems to be Solved by the Invention The present invention aims to improve the storage characteristics and battery voltage of a nonaqueous electrolyte battery that uses cupric oxide as a positive electrode active material and lithium or a lithium alloy as a negative electrode active material. This is the purpose.

B) Means for Solving the Problems The present invention is characterized in that molybdenum trisulfide and iron disulfide are added to a positive electrode containing cupric oxide as an active material.

(e) Effect When molybdenum trisulfide is added to a positive electrode that uses cupric oxide as an active material, the decomposition of cupric oxide is suppressed, and the sulfur produced by dissolving a part of molybdenum trisulfide is It exists as a film on the surface of the lithium negative electrode, and can suppress the precipitation of metal steel on the surface of the lithium negative electrode.

Furthermore, adding iron disulfide can increase the battery voltage, although the reason is not clear.

(f) Example Examples of the present invention will be described in detail below.

Acetylene black and graphite as conductive agents are added to 85% by weight of a positive electrode mixture of 80% by weight of commercially available special grade second oxide steel, 5% by weight of molybdenum trisulfide and 15% by weight of iron disulfide, and 10% by weight of acetylene black and graphite as conductive agents. , fluororesin powder 5 as a binder
After adding a weight of 9 and mixing thoroughly, this mixture was pressure molded at a pressure of about 2 tons/d to a diameter of 15.0j01. Thickness 1.
A molded body of 1111 was obtained, and this molded body was heated at 200 to 300°C.
The positive electrode is then heat-treated at a temperature of .

The negative electrode is made by rolling a lithium plate to a thickness of about α6MR, and this lithium rolled plate is made into a diameter of 15mm. It was punched off.

The electrolyte was prepared by dissolving 1 mole of lithium perchlorate in a mixed solvent of propylene carbonate and 1.2 dimethoxyethane, and Sebaret P was made of polypropylene nonwoven fabric with a diameter of 11,6111 mm. *Mi3.4 fin battery (A)
It was created.

Figure 1 shows a longitudinal cross-sectional view of the battery of the present invention, in which (1) is a positive electrode using cupric oxide as an active material and added with molybdenum trisulfide and iron disulfide, (2) is a lithium negative electrode, and (3) is an electrolytic electrode. A separator impregnated with liquid. In addition, (4) is the positive electrode ring, (
5) is a positive electrode current collector, (6) is a negative electrode current collector, (71 (81
(9) is the positive and negative electrode outer can, and (9) is the insulating backing.

Next, in order to investigate the superiority of the battery of the present invention, a comparative battery (B) was prepared which was the same as the battery of the present invention except that molybdenum trisulfide and iron disulfide were not added to the cupric oxide positive electrode.

FIG. 2 shows the change in internal resistance over time when these batteries were stored at a temperature of 60° C. and a humidity of 90%.

In addition, Figure 6 shows the discharge characteristics of these batteries at 20°C 15,6 Ω constant load discharge, and the solid line is the initial characteristic;
.

The broken line shows the discharge characteristics after storage for 20 days under conditions of a temperature of 60° C. and a humidity of 90%.

As shown in Figures 2 and 3, the original 8A battery (A) is the comparison battery (
It can be seen that, compared to B), the storage characteristics especially under high temperature and high humidity are improved, and the battery voltage is increased.

Considering the reason for this, in the battery of the present invention, when molybdenum iosulfide is added to the positive electrode that uses cupric oxide as an active material, the decomposition of cupric oxide is suppressed, and a portion of molybdenum trisulfide is The sulfur produced by dissolving sulfur exists as a film on the surface of the lithium negative electrode, so even if cupric oxide decomposes and metal steel dissolves in the electrolyte, metal steel will precipitate on the surface of the lithium negative electrode. It is thought that this suppresses the increase in internal resistance and improves storage characteristics.

Note that the sulfur film is easily peeled off by discharge, so it does not adversely affect the discharge characteristics.

Also, although the reason why the stain voltage is increased by adding iron disulfide is not clear, iron disulfide has a higher specific potential than cupric oxide, so when cupric oxide is used alone It is assumed that the battery voltage will also increase.

(g) Effects of the invention As mentioned above, in a non-aqueous electrolyte battery equipped with a positive electrode made of oxidized second steel as an active material, by adding molybdenum trisulfide and iron disulfide to the positive electrode, excellent storage characteristics can be achieved. It is possible to obtain a high-voltage non-aqueous electrolyte battery, and its industrial value is extremely large.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of the battery of the present invention, FIG. 2 is a diagram showing the relationship between internal resistance and storage period, and FIG. 3 is a diagram showing the discharge characteristics of the battery. (11... Positive IE, (21... Negative electrode, (31... Separator, (4)...
Positive electrode ring, (5)・・・=・Positive electrode current collector, (6)・
...Negative electrode current collector, (71 (8+...Positive and negative electrode outer can, (9)...Insulating backing, (A)
...Battery of the present invention, (B) ...Comparison battery.

Claims (1)

[Claims] (1) A negative electrode containing lithium or a lithium alloy as an active material, a non-aqueous electrolyte, and a positive electrode containing cupric oxide as an active material, the positive electrode containing molybdenum trisulfide and iron disulfide. A non-aqueous electrolyte battery characterized by the addition of additives.