JPS6264063A - Nonaqueous electrolyte battery - Google Patents

Abstract

PURPOSE:To suppress an increase in internal resistance without a decrease in the mechanical strength of positive electrode by adding 0.5-2.0wt% of fluorine resin as a binder to a positive electrode using cupric oxide as active material. CONSTITUTION:For example, 89wt% cupric oxide of commercial guaranteed reagent, 10wt% graphite serving as conductive material, and 1.0wt% fluorine resin serving as binder are mixed to a positive mix. The positive mix is molded at a pressure of about 2 tons per cm<2> to obtain a molding measuring 15.0mm in diameter and 1.1mm in thickness. The molding is heated at 200-300 deg.C to form a positive electrode.

Description

DETAILED DESCRIPTION OF THE INVENTION G) Industrial Field of Application The present invention relates to a non-aqueous electrolyte battery C using cupric oxide as a positive electrode active material, and more particularly to an improvement in the positive electrode.

(→Conventional technology) Non-aqueous electrolyte batteries have attracted much attention due to their advantages of high energy density and low self-discharge, and a representative example of this is disclosed in Japanese Patent Publication No. 57-4064. There is a manganese dioxide-lithium non-aqueous electrolyte battery.

By the way, the positive electrode used in this type of battery C2 is generally prepared by pressure molding a positive electrode mixture prepared by adding and mixing an active material with a conductive agent and a binder. Although the binder is indispensable from the viewpoint of mechanical strength of the electrode, it is undesirable from the viewpoint of battery reaction since it inhibits the movement of electrons and lowers the conductivity.

According to the prior art (Japanese Patent Publication No. 57-4064), when manganese dioxide is used as the positive electrode active material, a small amount of the binder is added.

(c) Problems to be Solved by the Invention The present invention aims to improve the battery characteristics of a non-aqueous electrolyte battery using cupric oxide as a positive electrode active material.

) The method to solve the problem was originally f! A indicates that 05 to 2.0% by weight of fluororesin is added as a binder to a positive electrode containing cupric oxide as an active material.t-
Features.

(E) Effect According to the present invention C2, the increase in internal resistance can be completely suppressed without reducing the mechanical strength of the positive electrode, and the battery characteristics can be improved.

(f) Implementation example The implementation of the present invention will be described in detail below.

Commercially available % cupric oxide '89 weight'' i%c graphite as a relaxing agent and fluororesin powder as a binder 1.
After adding 0% by weight and mixing, this positive electrode mixture was mixed at a rate of about 2 tons/
- Pressure molded at a pressure of 15. A molded body having a thickness of 1.1 u is obtained, and this molded body is heat-treated at a temperature of t200 to 300°C to form a positive electrode.

For the negative electrode, a lithium plate was rolled to a thickness of about Q, (mg), and this lithium rolled plate was punched out to a diameter of 15.0 mm.The electrolyte was a mixture of propylene carbonate and 1°2 dimethoxyethane. Mixed solvent C: using a solution of 1 mol/l of stium perchlorate, and using a polypropylene nonwoven fabric as a cenolator, with a diameter of 20.011 mm,
Thickness 2.5a OJ original Il! 11 Battery (A)' (e
For comparison, cupric oxide 9 was prepared without adding fluororesin.
The first comparison battery (B), which was the same as the present invention except that 10% by weight of graphite as a conductive agent and mixed with t- was used as the total positive electrode mixture, and 85% by weight of cupric oxide. %C;
5% by weight of fluororesin as a binder and 10% by weight of graphite as a conductive agent were all added and mixed rLE polar mixture was used and the rest was the same as the present invention Second comparative battery (C) All were prepared. .

Figure 1 shows all the characteristics of these batteries after being stored at 60°C for 6 months, with a load of 1Ω at 20°C, and Figure 2 shows the characteristics of these batteries under conditions of 60°C and 90% humidity. It shows the change in internal resistance over time during storage.

Further, FIGS. 6, 4, and 5 show the relationship between the amount of binder (fluororesin) added and the discharge capacity, battery swelling, and internal resistance.

@ From Figures 1 and 2, the present invention battery (A) is the comparison battery CB.
) (C) (It can be seen that the battery characteristics have been improved.

Considering the reason for this, cupric oxide is manganese dioxide C
Because it has good moldability, it maintains mechanical strength even if the amount of binder added is completely destroyed. This is thought to be due to the fact that since the amount of binder added is reduced, the conductivity of the positive electrode is improved and the increase in internal resistance is suppressed.

In addition, α5-2.
It can be seen that the range of 0 weight width is preferable.

(g) Effects of the invention As mentioned above, in a non-aqueous battery using a positive electrode mainly made of cupric oxide gold active material, positive electrode g: addition of fluororesin as a binder. Amount f! :o, s~2
．． Setting it to 0% by weight (secondly, it is possible to improve the pond properties), and its industrial value is extremely large.

[Brief explanation of the drawing]

Figure 1 shows the discharge characteristics of an 'IE cell at a temperature of 20°C and a 1Ω load after storage for 6 months at a temperature of 60°C.
Figures 6 to iXS diagrams show the relationship between discharge capacity, battery swelling, and internal resistance with respect to the amount of binder (fluororesin) added. It is a diagram. (A)...Battery of the present invention, CB) (C)...Comparison battery.

Claims (1)

[Claims] (1) A positive electrode containing cupric oxide as the main active material, a negative electrode containing lithium or a lithium alloy as the active material, and a non-aqueous electrolyte, the positive electrode containing a fluororesin as a binder. A nonaqueous electrolyte battery characterized in that 0.5 to 2.0% by weight is added.