JPS6017858A - Nonaqueous electrolyte battery - Google Patents

Abstract

PURPOSE:To reduce the internal resistance of a nonaqueous electrolyte battery and increase its reliability by improving the current-collecting ability of the current collector, increasing its strength and by preventing any deformation of the current collector which might be caused during manufacture when it is punched into a given shape from a metal sheet by using as the current collector a metallic net presed into a rugged configuration. CONSTITUTION:A metallic net prepared by punching a metal sheet into a given shape and pressed into the desired shape is used in making a nonaqueous electrolyte battery in which the above metallic net is used as a current collector 26. In the current collector 26 or the metallic net pressed into the desired shape, vertical linear members 26a and horizontal linear members 26b closely touch each other thereby preventing them from moving apart from each other. Thus, the many linear members are electrically unified with security to form the current collector net 26 which can exhibit a sufficient current-collecting ability. As a result, a stable and superior current-collecting ability can be realized, thereby securing the reduction of the internal resistance of the battery for example.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an aqueous electrolyte battery, particularly one using a metal net as a current collector.

For example, in a flat non-aqueous electrolyte battery, a current collector is used in contact with the active material of the positive or negative electrode in order to lower its internal resistance. Since non-aqueous electrolyte batteries generally have high internal resistance, bringing a current collector into contact with each positive electrode or negative electrode is very effective in lowering the internal resistance.

By the way, expanded metal or metal net is often used as the current collector. Expanded metal is suitable as a current collector, but has the drawback of being expensive. On the other hand, although metal nets are low-cost, the wire rods that make up the metal net are easily disassembled into pieces, and the vertical wire rods and horizontal wire rods that make up the metal net do not come into contact with each other reliably. , because of this, it cannot perform a sufficient function as a current collector.
There were problems like this.

FIG. 1 shows an enlarged portion of a current collector 26 used in a conventional non-aqueous electrolyte battery. J shown in the same figure, 43 LJ metal nets 1 to 7') 1 in a conventional non-aqueous electrolyte battery.
1. With the current collector 2G that vibrates (Jl, the vertical wire 26a and the horizontal wire 26b that make up the net 1-, there are many platforms where the feed is caught), so this is used as the current collector. Enough to use 2
The problem arises that the TEPCO effect is not exhibited. If the vertical wire rods 26a etc. (corruption 261 of ^1) are not securely in close contact or in contact with each other, the fully bent wires 1~ constituting the current collector 26 are likely to disintegrate into pieces. In particular, when punching out a current collector 26 with a predetermined contour shape from a fully bent net l-1]r Ironaru R1 shrine, the punched current collector 26
J5 LJ wire detaches or falls off at the edge of the
This U1nI2 or fallen wire pieces often get mixed into the inside of the battery and cause an internal short circuit. In addition, if the vertical wire rod 26a and the horizontal wire rod 26b are separated from each other, the wire rods constituting the nets 1~ are likely to move freely, which reduces the strength of the current collector 26. The wire becomes easily deformed or deformed, or a part of the wire becomes detached or falls off during handling.

As described in 1-1 below, in conventional non-aqueous electrolyte batteries that use metal nets as current collectors, the internal resistance cannot be lowered sufficiently because the current collectors do not exhibit sufficient current collection effects. Further, there were problems in that the current collector had low strength, was easily deformed, and was difficult to handle.

This invention was made in view of the conventional problems as described below, and its purpose is to use a relatively low-cost metal net 1 as a current collector, and to In order to be able to fully demonstrate the current collecting effect, it is possible to reliably lower the internal resistance, increase the strength of the current collecting wood, prevent it from deforming, and handle it roughly. It is an object of the present invention to provide a non-aqueous electrolyte battery which can be simplified and whose production suitability can be greatly improved.

In order to achieve the above object, the present invention has a metal net 1 punched into a predetermined contour shape as a current collector, and is characterized in that the metal net is pressed from the direction of its thickness. shall be.

3- Hereinafter, preferred embodiments of the present invention will be described based on the drawings.

In addition, the middle part or the correspondingly covering part in each figure is indicated by the same reference numeral.

FIGS. 2 and 3 show an embodiment of a non-aqueous electrolyte battery according to the present invention.

FIG. 2 shows a portion of the current collector 26 used in the non-aqueous electrolyte battery shown in FIG. 3 in an enlarged manner.

First, the non-aqueous electrolyte battery shown in FIG. 3 will be explained. The non-aqueous electrolyte TX if! shown in FIG. In i, a power generation element 16 is loaded and sealed in a flat metal TJJ battery case 24. The cell case 21 includes a negative electrode terminal 18 made of metal, a positive electrode can 201 made of metal, and a gasket 22 made of metal. The negative four-stone terminal 18 forms a negative electrode side case portion of the battery case 24. The positive electrode can 20 also serves as a positive electrode terminal. The gasket 22 is compressed between the negative electrode terminal 18 and the positive electrode can 20 to provide space inside the case 24 .

The power generation element 16 is composed of a negative electrode active material 101 made of a light metal such as lithium, a separator 4-part 12 impregnated with a non-aqueous electrolyte, and a positive electrode active material 1/I mainly made of manganese dioxide or the like. .

A current collector 26 made of a metal net is interposed between the positive electrode active material 14 and the positive electrode can 20.

This current collector 26 is pressed in advance to the positive electrode active material 11 side, so that it bites into the positive electrode active material 14 and close electrical contact is established between the two.

Here, the metal net constituting the positive electrode current collector 26 is
As shown in the figure, those pressed from the thickness direction (arrow direction) are used. In this way, the metal net pressed from the thickness direction, that is, the current collector 26, is made up of the vertical wire rods 26a and the horizontal wire rods 2'6'b that make up the net.
and are in close contact with each other, restraining each other to prevent them from moving freely. As a result, a large number of wires constituting the net as the current collector 26 are electrically integrated reliably, and a sufficient current collecting effect can be achieved. Therefore, it is possible to achieve a stable and good current collection effect, and to reliably lower the internal resistance of a battery, for example. 261) Toga! j
Since they intertwine very closely, their mechanical strength is also increased, and deformation when handling them into a predetermined contour shape is prevented. . Furthermore, the shape retention of the net is also improved,
For example, a part of the wire may come off or fall off, causing an internal short circuit.B Prevention 1
1- Become.

Here, to show a more preferable embodiment of the present invention, first, the metal net 1 to 1 as the current collector 26 (it is desirable that the mesh is 120 mesh or more. This is because it is difficult to obtain a close electrical contact with the active material, which makes it difficult to obtain a sufficient current collection effect.Furthermore, if the mesh becomes coarser than 120 meshes, the pair of wires and the horizontal wires The intertwining between them becomes insufficient, and the shape retention 111 of the net decreases.

Next, as the current collector 26? In case 1~, the wire diameter of the wires IJ26a and 26b composing the net is 30~
A range of 200μ is desirable.

If the wire diameter is less than 30 μm, sufficient penetration into the active material cannot be achieved, resulting in a decrease in the current collecting effect. Further, if the wire diameter exceeds 200 μm, it becomes difficult to bring the vertical wire rod 26a and the horizontal wire rod 26b into reliable contact even if the net of A is pressed from the thickness direction. Also vertical line)rA
The number of electrical contact points between the wire rod 26a and the horizontal wire rod 26h is reduced, causing problems such as insufficient current collection effect.

As described above, the non-aqueous electrolyte battery according to the present invention improves the current collection effect by simply adding an extremely simple configuration of using a pre-pressed metal net as a current collector. , it is possible to increase the strength of the current collector and prevent deformation when punching into a predetermined contour shape. By these means, internal resistance can be reliably lowered and reliability can be greatly improved.

7-

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing the current collector portion of a conventional non-aqueous electrolyte battery, and FIG. 2 is an enlarged cross-sectional view of the current collector portion of the non-aqueous electrolyte battery according to the present invention. , Figure 3 shows this invention J:
1 is a sectional view showing an example of a non-aqueous electrolyte battery. 10... Negative electrode active material 12... Separator 14... Positive electrode active material 16... Power generation element 18... Negative electrode terminal 20... ...Positive electrode 1h22...Gasket 1-24...
・Battery case 26...Current collector 26a made of metal net 1-...Vertical wire rod 26b...Horizontal wire Patent applicant Fuji Electrochemical Co., Ltd. 1st generation Patent attorney - Kensuke Iro 8- Third plan 7!

Claims (1)

[Claims] (1) A non-aqueous electrolyte battery having a metal net punched into a predetermined contour shape as a current collector, characterized in that the metal net is pressed from the direction of its thickness. Non-aqueous electrolyte battery. (2. A non-aqueous electrolyte battery according to claim (1), characterized in that the metal net has a wire diameter of 30 to 200μ. (3) Claim (1) or (2) ), wherein the metal net has a mesh size of 120 meshes or more. (4) In the battery according to claim (1), (2) or (3), the metal net has a mesh size of 120 or more. A non-aqueous electrolyte battery characterized in that a net is interposed as a positive electrode current collector between a positive electrode active material and a metal positive electrode can housing the positive electrode active material.