JPS6151765A - Nonaqueous battery - Google Patents

Abstract

PURPOSE:To obtain an oxyhalide battery having high capacity by using high cohesive carbon as positive current collector material. CONSTITUTION:Thionyl chloride is used as positive active material. A solution prepared by adding aluminium chloride and lithium chloride to thionyl chloride is used as electrolyte. A positive current collector 4 is produced by applying high cohesive carbon paste comprising ''Teflon'' binder and water on an expanded nickel net, then drying in a vacuum condition. Carbon having a value exceeding a dibutyl phthalate absorption of 210ml/100g is used. A negative electrode 2 is formed by pressing a lithium film against a nickel current collector net. A separator 3 consists of glass fiber. A battery is formed by placing the positive current collector in the center and placing the negative electrodes on its both sides with the separators interposed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an oxyhalide battery which has a higher capacity than conventional oxyhalide batteries and can be used as a power source for all cordless devices or as a memory backup power source.

BACKGROUND OF THE INVENTION Nonaqueous batteries using oxyhalides as positive electrode active materials have been developed in which thionyl chloride, sulfuryl chloride, etc. are used as oxyhalides, and lithium, which is active metal, is used as negative electrode active materials.

In this oxyhalide battery, since the positive electrode active material is a liquid, it is necessary to cause a discharge reaction in a porous positive electrode current collector. Therefore, thermal black, furnace black, and activated carbon-based carbon were evaluated as positive electrode ijA electric material, and as a result, acetylene black, a type of thermal black, came to be used.
,N.Dey.

J, P0Vlr 5sources, 5 (
1980) 57).

This is because the positive 8i TEPCO body made of acetylene black has a lower packing density than current collectors using other carbons, and therefore the tli capacitance per unit weight of carbon becomes too large.

Problems to be Solved by the Invention In recent years, with the increase in the density of electronic equipment, it has been desired that these M sources also have a higher energy density. In order to meet these demands, the present invention not only elucidated the physical properties of the positive electrode iTi material, which had not been made clear in the past, but also developed an oxyhalide battery with a higher capacity than conventional batteries based on these results. The purpose is to obtain.

Means for Solving the Problems The present invention provides an oxyhalide battery with an unprecedented high capacity by using highly agglomerated carbon in place of acetylene black, which is a conventional positive electrode current collector material. be.

As a factor for evaluating the physical properties of working carbon, there is oil absorption m, which indicates the degree of carbon aggregation (strafture) (Carbon Black Handbook, edited by Carbon Black Association, 1 Tosho Publishing Co., Ltd., p. 169). Oil absorption is a method using dibutyl phthalate with a certain m of oil required to fill the voids in carbon, as specified by ASTM and Japanese Industrial Standards (JIS).
K6221) l: Specified. The specific surface area of carbon and the degree of carbon aggregation are important factors for batteries because they affect the porosity 9m pore distribution of the positive electrode. The oil absorption m of carbon that has been evaluated for batteries so far is 210 m1 /100 of acetylene black.
g is -mQ, and no tests have been conducted on carbon with higher agglomeration.

In an oxyhalide battery, during discharge, a reduction reaction of oxyhalide occurs in the positive electrode Toden, and among the reaction products, salts in the positive electrode active material that are insoluble in the oxyhalide solvent are
Precipitates within the positive electrode current collector.

The discharge ends when the discharge products are deposited on the current collector reaction surface.

With the exception of special-purpose oxyhalide batteries that discharge at such a high rate that diffusion becomes dominant in the discharge reaction, the discharge capacity of ordinary batteries is limited by the precipitation of insoluble salts into the positive electrode current collector during discharge. , determined by the void volume of the current collector.

Acetylene black, which is the material for the positive electrode current collector of conventional batteries, has advanced carbon agglomeration, so when used as a current collector, it has an extremely high porosity, resulting in a large value of discharge capacity per unit weight of carbon. It will be done.

The present invention provides an oxyhalide battery with an unprecedented high capacity by creating a positive electrode current collector using zero agglomeration carbon, which has never been tested for battery use, and making it into a battery. It is.

The carbon used for this purpose is Ketjen Black (a type of furnace black supplied by Akzo of the Netherlands).
Carbon black, such as EC (Carbon Black, translated by Koike Takahashi, published by Kodansha Entific) and highly conductive carbon black manufactured by Mitsubishi Yuka Co., Ltd., is used when carbon is oxidized to a high degree of agglomeration. It is possible.

Embodiment FIG. 1 shows an embodiment of a battery according to the present invention. In the figure, (1) is a battery case, (2) is a negative electrode, (3) is a separator, and (4) is a positive electrode current collector. , (5) is a liquid injection pipe. Thionyl chloride was used as the positive electrode active material, and 1.5 M of aluminum lithium chloride was added to the thionyl chloride to form an electrolyte. The positive electrode current collector was prepared by applying highly agglomerated carbon paste-formed with water together with a Teflon binder to an expanded nickel current collection network and drying it in vacuum. The negative electrode was used by pressing a lithium thin film onto a nickel current collection network. The separator was made of glass fiber with a porosity of 92%, and the battery had a bicell structure with a positive electrode current collector in the center and lithium on both sides with separators interposed therebetween. Injection of lithium aluminum chloride/thionyl chloride solution into the battery is as follows:
This was done via the liquid injection tube in 5).

For comparison, a battery with a positive electrode current collector using acetylene black was assembled and the battery characteristics were compared.

The discharge test was conducted by discharging the battery at a constant current of 10 mA/col per square inch surface area of the positive electrode current collector.

Table 1 shows the physical properties of the positive electrode current collector used in the battery Δ of the present invention and the positive electrode current collector of the conventional battery B, and FIG. 2 shows the discharge characteristics of each battery.

The specific resistance of carbon is a value when the bulk density is the same as that of the positive electrode current collector.

Furnace black carbon was used as the highly agglomerated carbon.

Table 1. Physical Properties of the Positive Electrode Current Collector and Current Collector Carbon The discharge capacity of conventional battery B using acetylene black as the positive electrode current collector material is 1.35 Ah/per carbon unit type.
g, whereas in battery A of the present invention, it was 1.8Ah/
g, a 33% increase in capacity.

Also, positive electrode 1 made of highly agglomerated carbon! The specific resistance of the electric body is 1! 115 or lower, and the discharge voltage was also improved from 3.18 V of the conventional battery to 3.26 V.

The oil absorption port of acetylene black, which is a conventional carbon material, is used for carbon for oxyhalide batteries as described above.
By using highly agglomerated carbon that exhibits an oil absorption amount exceeding m1/100a, it is possible to manufacture an oxyhalide battery with a higher capacity than conventional batteries.

In this example, furnace black with an oil absorption rate of 390 ml/100 g was used, but the average oil absorption rate was 4 U! By discharging at 101 nA/cot per apparent surface area of the J electric body, the capacity is increased by 33% compared to the discharge capacity of conventional batteries, and the discharge voltage is also improved by 80 mV, resulting in an extremely large improvement in battery capacity. became.

Although thionyl chloride was used as the positive electrode active material in this example, similar effects can be expected even if sulfuryl chloride is used.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of the battery according to the present invention, and FIG. 2 is a 1g II battery A according to the present invention and a conventional battery B.
It is a discharge characteristic diagram at A/cut. 1... Battery case, 2... Negative electrode, 3... Separator, 4
...Positive electrode current collector, 5...Liquid injection tube

Claims (1)

[Claims] 1. In a nonaqueous battery that uses oxyhalide as the positive electrode active material, carbon black or a composite of carbon black and a conductor, etc. as the positive electrode current collector, and uses an active metal as the negative electrode active material, the positive electrode current collector is A non-aqueous battery characterized in that the eggplant carbon exhibits a dibutyl phthalate oil absorption amount exceeding 210 ml/100 g as specified in Japanese Industrial Standards JIS K6221.