JPS60148056A - Alkaline manganese battery - Google Patents

Abstract

PURPOSE:To increase the discharge capacity of an alkaline manganese battery by preparing the positive mixture by combining manganese dioxide with specified amounts of graphite fluoride and a conductive agent and a small amount of an organic binder. CONSTITUTION:A alkaline manganese battery is assembled using a positive mixture prepared by mixing 100pts.wt. of manganese dioxide with 20-100pts.wt. of graphite fluoride represented by formula (C2F)n, a conductive agent such as acetylene black and a small amount of an organic binder. The theoretical electric capacity of graphite fluoride contained in the positive mixture is greater than that of manganese dioxide. When this positive electrode is combined with a negative zinc electrode in an alkali electrolyte bath, flat electric discharge of about 1.20V is performed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to improvements in alkaline manganese batteries using manganese dioxide as a depolarizer.

Conventional configurations and their problems In recent years, compact electronic devices such as cameras, electronic wristwatches, and hearing aids have become widespread. Silver oxide batteries and mercury batteries are used as power sources for these devices.

Small button batteries, mainly alkaline manganese batteries, are often used. Among these, silver oxide batteries are expensive, and mercury batteries have pollution problems, so
Alkaline manganese batteries, which have a higher voltage than mercury batteries and are made of cheaper materials, are now being reconsidered and increasingly used. Along with this, there is an increasing demand for improving the sustaining voltage during discharge and increasing the electric capacity of alkaline manganese batteries.

Conventionally, alkaline manganese batteries have generally used a positive electrode mixture made of γ-type manganese dioxide as a main material, mixed with a small amount of graphite powder as a conductive agent, and compression-molded. However, in a battery with such a configuration, the voltage gradually decreases during discharge, and 1. Most precision equipment using LSI circuits that require a discharge voltage of IV or higher have the disadvantage that only a portion of the total electrical capacity can be used.

In order to solve this problem, alkaline manganese batteries have been proposed, which are mainly composed of manganese dioxide and mixed with mercury oxide and a conductive agent, but the mercury oxide contained turns into metallic mercury after discharge, which generally causes pollution problems. It has been raised.

OBJECTS OF THE INVENTION The object of the present invention is to eliminate the above-mentioned drawbacks of alkaline manganese batteries and to increase the discharge capacity at 1.1 V or higher.

Structure of the Invention The present invention provides a positive heptode mixture containing manganese dioxide with the formula (0
2F) It is composed of a mixture of fluorinated graphite represented by n, a conductive material, and a small amount of an organic binder, and the fluorinated graphite content of the positive electrode mixture is 20 to 20 parts by weight per 100 parts by weight of manganese dioxide.
The amount was 100 parts by weight.

The above-mentioned fluorinated graphite has a theoretical capacitance of manganese dioxide.
730mAh/g for C13o 8mAh/l
It is characterized by a flat discharge of about 1.20 V when combined with a zinc negative electrode in an alkaline electrolyte.

According to the present invention, it is possible to take advantage of the high electric capacity and voltage stability of fluorinated graphite.
The discharge voltage will be shown as follows.

Description of Examples As an example of the present invention, 50 parts by weight of (02F)n, 10 parts by weight of acetylene black as a conductive agent, and Teflon powder as an organic binder were added to 100 parts by weight of γ-manganese dioxide produced by electrolysis. 3 parts by weight are mixed and press-molded to obtain a positive electrode mixture.

Figure 1 shows an LR44 (diameter 11 mm) using the above-mentioned positive electrode mixture.
This shows a button-type alkaline manganese battery with a total height of 6.4.

1 is nickel-plated iron positive electrode case, 2 is case 1
3 is a separator, 4 is an electrolyte-containing agent, 6 is a negative electrode mixture made of zinc powder mixed with a thickener, 6 is a sealing plate that also serves as a negative electrode terminal, and 7 is a sealing ring. It is.

A battery having the above configuration is designated as A, and as a comparative example, a battery using a polar mixture in which 10 parts by weight of graphite is mixed with 100 parts by weight of manganese dioxide is designated as B. Figure 2 shows two of these batteries.
The characteristics when continuously discharged with a 30Ω load at 0°C are shown.

It can be seen that battery A shows an increase in capacity of about 30 cm compared to battery B.

In addition, in the present invention, (C
2F)n is 20 per 100 parts by weight of manganese dioxide
If it is less than part by weight, it will hardly participate in the reaction. Also, 1
If the amount exceeds 00 parts by weight, pellet molding becomes difficult due to the lack of moldability of (C2F)n.

The battery structure becomes difficult and the battery is not stable.0 Effects of the Invention As described above, according to the present invention, the discharge capacity of an alkaline manganese battery can be improved and its applications can be further expanded.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of an alkaline manganese battery in an example of the present invention, and FIG. 2 is a diagram showing the discharge characteristics of the battery. 2... Positive electrode mixture, 3... Separator,
5...Negative electrode] Name of agent: Patent attorney Toshio Nakao and 1 other person 1 Figure 3

Claims (1)

[Claims] Manganese dioxide, which is the main component of the depolarizer, has the formula (C2F)n
A positive electrode mixture is prepared by mixing fluorinated graphite represented by , a conductive agent, and a small amount of an organic binder, and the content of fluorinated graphite in the positive electrode mixture is 20 to 100 parts by weight per 100 parts by weight of the manganese dioxide. An alkaline manganese battery characterized by: