JPS5998470A - Organic solvent cell - Google Patents

Abstract

PURPOSE:To make the reaction effective area of a positive pole large even at heavy load and thereby improve a discharge characteristic, by interposing a conductive porous layer between the positive pole and an electrolyte holding material. CONSTITUTION:A collector body 12 is disposed on the bottom surface of a stainless steel case 11 doubling as a positive terminal, on which a positive pole 13, a conductive porous layer 4 holding an electrolyte, an electrolyte holding material 15 and a negative poles 16 are piled in layers one after another in order, then these element are sealed up with a sealing plate 17 doubling as a negative terminal via a packing 18. The conductive porous layer 14 is composed of a carbon fiber, a non-woven fabric or a woven fabric of a conductive fiber such as a metallic fine fiber, etc., and kept up with an electrolyte of an organic solvent. According to this organic solvent cell, the conductive porous layer 14 is interposed between the positive pole 13 and the electrolyte holding material 15, and this porous layer is electrically connected to a case 11 which doubles as a positive terminal. Therefore, a current collection effect in the positive pole is sharply improved so that an electrode reaction effective area of the positive pole groes large.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an organic solvent battery having an improved current collection method for a positive electrode.

A conventional organic solvent battery is shown in FIG. In this organic solvent battery, a current collector 2, a positive electrode 3, an electrolyte holding material 4, and a negative electrode 5 are sequentially laminated in a container 1 which also serves as a positive electrode terminal, and the battery is sealed with a sealing plate 6 via a backing 7. , a light metal such as lithium or sodium is used for the negative electrode 5, and a certain amount of solvent is used as the electrolyte.

This organic solvent battery has a higher energy density and higher reliability than silver oxide batteries, alkaline manganese batteries, etc.

For this reason, they are used in various electronic devices, and as their uses expand, various battery characteristics are required. For example, when used as a watch battery, heavy load characteristics are important in order to support lamp lighting, alarm activation, etc.

That is, when a watch (-) is turned on and a large current is drawn due to lighting a lamp, activating an alarm, etc., the terminal voltage drops, but if the voltage drops too much below a predetermined voltage, the liquid crystal drive unit, etc., which operates on a steady current, will go awry. For this reason, there is a need for characteristics that allow the voltage to be maintained at a predetermined level or higher even when a large current is drawn.

In order to obtain excellent heavy load characteristics, it is necessary for the reaction of the positive electrode active material to proceed uniformly in each part of the positive electrode.On the other hand, the positive electrode active material is generally in contact with an electronic conductor such as the current collector 2. It is known that the electrode reaction is most likely to occur in this area, especially during heavy load discharge.

However, in the conventional battery, as mentioned above, the positive electrode 3 is connected to the container 1.
(2) Only one side is in contact with the installed current collector 2. Therefore, during heavy loads, the electrode reaction tends to concentrate on one side, and there is a problem that the effective electrode reaction area of the positive electrode appears smaller than the actual positive electrode area. Ta.

As a means to solve this problem, there is a method in which a wire mesh or expanded metal is crimped onto the surface of the positive electrode 3 that is in contact with the electrolyte holding material 4, and the peripheral portion is brought into contact with the positive electrode terminal (two contacts). According to this method, the electrode reaction occurs. is also generated on the surface in contact with the electrolyte holding material 4, making it possible to increase the effective electrode reaction area of the positive electrode.

However, if a wire mesh or the like is provided, the space inside the battery becomes narrower, and the capacity of the positive electrode must be reduced.

Moreover, since the surface of the positive electrode 3 in contact with the electrolyte holding material 4 is covered with a wire mesh or the like, there is a problem that the battery reaction is inhibited.

The present invention has been made in view of the above-mentioned circumstances (2), and its purpose is to increase the effectiveness of the positive electrode reaction under heavy loads without reducing the positive electrode capacity or inhibiting the battery reaction. The objective is to obtain an organic solvent battery that has a large area and can obtain excellent heavy load characteristics.

That is, the present invention provides an organic solvent battery in which a positive electrode and a negative electrode made of a light metal are stacked together with an electrolyte holding material interposed therebetween, and an organic solvent is used as the electrolyte. A conductive porous layer is interposed between the porous layer and the porous layer is electrically connected to the positive terminal.
shall be.

The present invention will be described below with reference to illustrative embodiments. Second
The figure is a cross-sectional view of an organic solvent battery.

In this organic solvent battery, a conductor 12 is placed on the bottom of a stainless steel container 11 which also serves as a positive electrode terminal, and a positive electrode 13 is placed on top of the conductor 12.
A conductive porous layer 14 for holding an electrolytic solution, an electrolytic solution holding material 15, and a negative electrode 16 are laminated in this order, and these are sealed via a backing 18 with a sealing plate 17 that also serves as a negative electrode terminal.

The positive electrode 13 is formed by mixing a positive electrode active material such as manganese dioxide with a conductive material and a binding material, and press-molding the mixture into a disk shape. The conductive porous layer 14 provided on this positive electrode 13 is
Formation of a conductive film on the surface of a non-woven or woven fabric made of conductive fibers such as carbon fibers or fine metal fibers, or a non-woven fabric or woven fabric made of non-conductive materials such as synthetic resin fibers or glass fibers that are stable in batteries. These are punched out into a disc shape and formed into a cup shape with a brim. The brim portion 14a of this porous layer 14 is in contact with the bottom surface of the container 11.

Further, the porous layer 14 holds an electrolytic solution of an organic solvent.

Im porous! The electrolyte holding material 15 provided on the electrolyte holding material 14 is made of a non-conductive material such as a polypropylene non-woven fabric, and is impregnated with and held with an electrolyte of an organic solvent. In addition, the negative electrode 16
is made of light metals such as metallic lithium and sodium.

According to this organic solvent battery, the positive electrode 11 and the electrolyte holding material 1
A conductive porous layer 14 is interposed between the positive electrode terminal 5 and the conductive porous layer 14, which is electrically connected to a container 11 which also serves as a positive electrode terminal. Therefore, the current collecting effect of the positive electrode is greatly improved, and the effective electrode reaction area of the positive electrode is increased. As a result, the internal resistance of the battery during discharge can be kept low until the end of discharge, and the discharge utilization rate of the electrode can be increased. Furthermore, since the effective electrode reaction area of the positive electrode is large, it is possible to provide excellent heavy load characteristics.

Furthermore, since the conductive porous l1ii14 retains an electrolyte, it has the same function as the electrolyte retaining material 15. Therefore, there is no need to reduce the positive electrode capacity, and battery capacity and battery reaction can be maintained favorably.

Note that the present invention is not limited to a structure in which the conductive porous layer 14 is in direct contact with the container 11, but may be in a structure in which a conductive ring is provided to hold the porous layer 14 on the same side of the positive electrode, and the conductive porous layer 14 is in contact therebetween.

Next, the implementation of the present invention will be explained.

As a positive electrode, a conductive material and a binding material are mixed with manganese dioxide calcined at 400°C, and a disc-shaped (two-pressure molded) material is used.As an electrolyte holding material, a polypropylene nonwoven fabric with a thickness of 0.10 rttlR is used. The conductive porous layer was made of a non-woven fabric made of carbon fiber with a thickness of 0.10 cm, which was punched out and formed into a cup shape with a brim. Metallic lithium was used as the negative electrode, and carbonic acid was used as the electrolyte. Using an organic solvent (prepared by dissolving 1 mole of lithium diperchlorate) in which propylene and 1°2-dimethoxyethane were mixed at a volume ratio of 1:1, an organic solvent battery according to the present invention (see Figure 2) was prepared. ) was created.

For comparison, a conductive porous layer with two-liquid retention ability was not interposed between the positive electrode and the electrolyte holding material (two configurations were used).
A conventional organic solvent battery (see FIG. 1) was prepared by setting the thickness of the electrolyte holding material to 0.2071111.

Batteries thus obtained: two, 50
A continuous 0Ω discharge was performed to perform accelerated evaluation of heavy load characteristics corresponding to clock lamp lighting, alarm activation, etc. The results are shown in FIG. In this case, curve A shows the characteristics of the battery of the present invention, and curve B shows the characteristics of the conventional battery.

As is clear from the experimental results shown in the figure (the two invention batteries are
The discharge voltage is higher than that of conventional batteries, and the discharge end voltage is 2.
．． The discharge utilization rate of the bridge was also high when Ov was set.

As described above, according to the present invention, a conductive porous layer is interposed between the positive electrode and the electrolyte holding material, and this porous layer has an electrolyte holding function and an electrode current collecting effect, so that heavy This has the remarkable effect of increasing the effective reaction area of the positive electrode under load and providing excellent discharge characteristics.

[Brief explanation of drawings]

Figure 1 is a cross-sectional view of a conventional organic solvent battery, Figure 2 is a cross-sectional view of an organic solvent battery showing an embodiment of the present invention, and Figure 3 is a comparison of the discharge curve of the battery of the present invention with that of a conventional battery. FIG. 11... Container, 12... Current collector, 13... Positive electrode,
14... Conductive porous layer, 15... Electrolyte holding material,
16... Negative electrode, 17... Sealing plate, 18...°) Arm resting. Applicant's representative Patent attorney Takeshi Suzue Pig box 1 Figure 3 omitted

Claims (3)

[Claims] (1) An organic solvent battery in which a positive electrode and a negative electrode made of a light metal are stacked together with an electrolyte holding material in between, and an organic hemorrhoid medium is used as an electrolyte (
=, an electroconductive porous layer for holding an electrolyte is interposed between a positive electrode and an electrolyte holding material, and the porous layer is electrically connected to a positive electrode terminal. Solvent battery. (2) The organic solvent battery according to claim 1, wherein the conductive porous layer is a nonwoven fabric or a woven fabric made of conductive fibers. (3) The conductive porous layer is formed by forming a conductive coating on the surface of a non-woven fabric or woven fabric made of a non-functional electrical substance that is stable in the battery. Organic solvent battery.