JPS60160566A - Nonaqueous electrolyte battery - Google Patents

Abstract

PURPOSE:To improve the discharge characteristic of a nonaqueous electrolyte battery by suppressing the increase in the internal resistance during the last stage of electric discharge by adding antimony sulfide to make the positive electrode containing iron disulfide as an active material. CONSTITUTION:After 80pts.wt. of commercial iron disulfide is combined with 10pts.wt. of acetylene black and graphite used as conductive agents and 4pts.wt. of a fluorine resin powder used as a binding agent, the mixture is thoroughly mixed to prepare a positive mixture which is then pressed and molded to form a pellet. The thus formed pellet is then sintered at 200-300 deg.C to make a positive electrode 1. A negative plate 4 is made by rolling a lithium plate into a thickness of 0.6mm. and punching the rolled plate into a diameter of 15.0mm.. Electrolyte is prepared by dissolving 1mol/l of lithium borofluoride into a mixture solvent consisting of propylene carbonate and 1,2 dimethoxyethane. The figure indicates the relationship among the quantity of antimony sulfide added, the utilization rate of the positive active material and the discharge capacity of the battery. As seen from the figure, it is preferable that the quantity of anitmony sulfide added be about 1.0-15.0wt% of the positive electrode.

Description

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

(b) Conventional technology Lithium, sodium, or their alloys are used as negative electrode active materials, and metal oxides, sulfides, chlorides, and halogen carbons7
j as the positive electrode active material, propylene carbonate, r-
Nonaqueous electrolyte batteries have high energy density and use an electrolyte prepared by dissolving inorganic salts such as lithium perchlorate, lithium borofluoride, and lithium aluminum in organic solvents such as butyllactone and 1.2 dimethoxyethane. ,
In addition, it has the advantage of low self-discharge, so it has attracted particular attention in recent years, and to date, 3.Ov-based non-aqueous electrolyte batteries have been proposed that use mango dioxide/enzyme fluoride as the positive electrode active material. .

On the other hand, if iron disulfide (FeSa) is used as a positive electrode active material as disclosed in Japanese Patent Publication No. 56-36794, a 1.5V non-aqueous electrolyte battery can be obtained, which can be used to replace existing dry batteries or alkaline batteries. It has the advantage of being able to replace dry batteries.

(c) Purpose of the Invention The purpose of the present invention is particularly to improve the battery characteristics of a 1.5V nonaqueous electrolyte battery using iron disulfide as a positive electrode active material.

(D) Structure of the Invention The present invention comprises a negative electrode using lithium, sodium, or an alloy thereof as an active material, a positive electrode using iron disulfide as an active material, and a non-aqueous electrolyte, the positive electrode comprising: A non-aqueous electrolyte battery characterized by adding antimony sulfide.

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

Antimony sulfide (Sbt S3)% as an additive, acetylene black and graphite as a conductive agent, and fluororesin powder as a binder were added to commercially available iron disulfide (Feat) at a weight ratio of 80i10:6:4. The mixed positive electrode mixture was pressure molded at a pressure of about 1 ton/c+n2 to obtain a pellet with a diameter of 15.0111111 and a thickness of 1.1 mm.Then, this pellet was fired at a temperature of 200 to 300°C to form a processed positive electrode. do.

The negative electrode is a lithium plate with 0.6111111 (7) J! X
This rolled plate was then punched to a diameter of 15.08 mm. The electrolyte is a mixture of propylene carbonate and 1.2 dimethoxyethane and 1 liter of lithium fluoroborate.
It is dissolved in mol/l.

FIG. 1 shows a cross-sectional view of the battery of the present invention, in which (1) is a positive electrode, which is pressure-welded to the inner bottom surface of a positive electrode can (2) via a positive electrode current collector (3), and (4) is the negative electrode and the negative electrode can (5
) is crimped onto the inner bottom surface of the negative electrode current collector (6). (7) is a separator made of polypropylene nonwoven fabric;
(8) is an insulating backing.

Figure 2 shows the battery of the present invention (A) and the conventional battery (B) at 20 degrees.
This is a comparison of the discharge characteristics and internal resistance characteristics when discharging at a constant load of 5.6 Ω at C.

Note that antimony sulfide was not added to the iron disulfide positive electrode of the conventional battery (B).

As is clear from FIG. 2, it can be seen that the battery of the present invention <A> has improved discharge characteristics by suppressing the rise in internal resistance in the latter stages of discharge compared to the conventional battery (B>).

Considering the reason for this, in the case of a conventional battery using only iron disulfide, the internal resistance is thought to increase in the late stage of discharge due to an increase in discharge products, although the reason is not clear. invention! In the case of a pond, it is thought that antimony sulfide as an additive participates in the reaction in the latter stage of discharge, and the reaction product of this antimony sulfide acts to suppress the increase in internal resistance of the positive electrode.

Figure 3 is a diagram showing the relationship between the amount of antimony sulfide added, the positive electrode active material utilization rate, and the battery discharge capacity. Figure 3 shows that the positive electrode active material utilization rate is 1, and the effect is greater than ON k%. However, the effect becomes almost constant at 20.0% by weight or more. In terms of battery discharge capacity, the effect appears at 1.0% by weight or more, and at 15.0% by weight it is only slightly more effective than when no additive is used.

Therefore, the amount of antimony sulfide added is preferably about 1.0 to 15.0% by weight based on the weight of the positive electrode.

(F) Effects of the Invention According to the battery of the present invention, since antimony sulfide is added to the positive electrode using iron disulfide as an active material, the increase in internal resistance in the late stage of discharge can be suppressed, and the discharge characteristics are improved.
In particular, it will greatly contribute to the practical application of 1.5V non-aqueous electrolyte batteries, which have a battery voltage that is almost the same as that of existing dry batteries and alkaline dry batteries.

[Brief explanation of the drawing]

Figure 1 is a longitudinal cross-sectional view of the battery of the present invention, Figure 2 is a comparison of battery characteristics between the battery of the present invention and a conventional battery, and Figure 3 is a graph showing the relationship between the amount of additives added and the discharge capacity of a flat battery using a positive electrode active material. It is a figure showing a relationship. (1)...Positive electrode, (2)...Positive electrode can, (3)...
Positive electrode current collector, (4)... negative electrode, (5)... negative electrode can,
(6)...Negative electrode current collector, (7)...Separator, (
8)...Insulating backing, (A)...Battery of the present invention,
(B)...Conventional battery. Applicant Sanyo Electric Co., Ltd. Agent Patent Attorney Shizuo Sano Fig. 1 5 Fig. 2 f Iodera No. 9 Sokugin (%) Fig. 3

Claims (1)

[Claims] ■ A negative electrode containing lithium, sodium, or an alloy thereof as an active material, a positive electrode containing iron disulfide as an active material, and a non-aqueous electrolyte, the positive electrode containing antimony sulfide. A non-aqueous electrolyte battery characterized by adding. ■The amount of antimony sulfide added is 1.
The non-aqueous electrolyte battery according to claim 0, wherein the content is 0 to 15.0% by weight.