JPH06150912A - Manufacture of battery and electrode plate - Google Patents

Abstract

PURPOSE:To extend lifetime of a cutting die, and reduce production cost, regarding a method for cutting a long-sized electrode plate comprising an active material deposited on a core material of porous metal. CONSTITUTION:An electrode plate 1 is cut with rotary cutters B and C sliding on the top with each other, while being automatically fed on the cutters B and C under rotating motion. Or, When a lug section D is formed for continuously cutting the plate 1, a pair of rotary cutters are constituted to continuously cut the plate 1 in the condition of D1/D2 between 1.5 and 3, provided that D1 is a diameter of one rotary cutter in contact with a metal core material, and D2 is a diameter of the other rotary cutter.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing an elongated electrode plate in which an active material is attached to a core made of a metal porous body, and a battery provided with the electrode plate obtained by this method. is there.

[0002]

2. Description of the Related Art Conventionally, a paste-type positive electrode plate for a non-aqueous electrolyte battery, a paste-type negative electrode punching metal for an alkaline storage battery, or a core of a metal porous body processed into a lath shape is filled with a predetermined active material. It is obtained by rolling the electrode original plate and cutting it into a predetermined shape.

Here, the cutting process of the original electrode plate is described in JP-A-64
As described in JP-A-52376, there has been an attempt to cut an electrode original plate having a predetermined active material attached thereto by a vertical press between a slit blade and a fixed blade, or to use a laser beam as cutting energy. .

[0004]

In such a conventional method, for example, when cutting with a slit blade, the blade is heavily worn, and the die material is secondarily processed in order to increase the strength of the blade, and the blade portion is cut. Since it is necessary to increase the strength, the die cost is inevitably high, and the production cost is high because the manufacturing method is not a continuous process but a batch system. Further, there are many problems in maintenance such as partial damage of the mold. In addition, in the case of cutting by using a laser beam as another method, a laser oscillating device is required and a huge capital investment is required. When cutting the battery electrode original plate, metal oxides, sulfides, halides, graphite, or carbon-based materials are used as the active material, so when cutting by heating with laser light, Since the active material is oxidized, the electrochemical capacity of the active material often decreases due to deterioration or burning of the active material.

To solve this problem, a manufacturing method in which the electrode original plate is continuously cut while being automatically fed by rubbing a pair of rotary blades having a substantially H-shaped cross section, as another method, a cross section having a substantially H shape is used. A method has been tried in which a pair of rotary blades having a mold shape are rubbed together to continuously cut the electrode original plate by automatically feeding the electrode original plate, but this type of electrode plate is composed of a metal material. Since it is composed of a material having completely different physical properties such as a metal porous body and a battery active material composed of a metal oxide, a sulfide, and a carbonaceous material, when cutting with a pair of rotary blades, the load applied to the electrode original plate is a metal porous body. Since the required pressure is different between the rotating blade that contacts the blade and the rotating blade that contacts the battery active material, if you try to cut with a blade of the same diameter, the electrode will meander or have many burrs To make a board There were many.

[0006]

In order to solve this problem, the present invention provides a method for manufacturing an electrode original plate in a manufacturing method in which the electrode original plate is automatically fed and cut by rubbing a pair of rotary blades having a substantially H-shaped cross section. The diameter of the rotary blade that contacts the porous metal body is made larger than the diameter of the rotary blade that contacts the other surface.

More specifically, when the diameter of the rotary blade contacting the porous metal body is D ₁ and the diameter of the other rotary blade is D ₂ , D ₁ /
It is set in the range of D ₂ = 1.5 to 3.0.

[0008]

With this manufacturing method, when the electrode plate having the active material filled and attached is automatically fed by the rotary blade and the electrode plate having a constant burr direction is required, or when the electrode plates having different burr directions are acceptable. In any of these cases, it is possible to continuously cut the electrode plate with uniform dimensional accuracy, and the manufacturing cost becomes low. In addition, since it is possible to continuously cut the electrode plate and wind it into a hoop with a winder, even if this hoop is incorporated into the production process of a battery equipped with this type of electrode plate, this hoop can be used in a battery production line. It can be automated and rationalized for the battery production line by directly supplying the battery.

[0009]

EXAMPLE An example of the present invention will be described below with reference to FIG.
It will be described together with (b).

FIG. 2 (a) is a sectional view of the main part of the front view showing a state in which the electrode original plate is being cut by the rotary blade of the present invention. FIG. 2B is a side view thereof. Electrode plate 1 is chemical
The main component is electrolytic manganese dioxide, which contains graphite as a conductive material and fluororesin as a binder, and constitutes the active material of the positive electrode. The active material 1a is filled in a core body 1b having a thickness of a metal porous body, specifically, a lath-processed nickel material. The electrode plate is cut by a pair of rotary blades B and C having a substantially H-shaped cross section with a predetermined width and a predetermined number of pieces, while the electrode original plate is automatically fed by the rotary blade in the direction of the arrow. In the case of this method, since the cut portion is not provided between the adjacent rotary blades, the burr direction of the cut electrode plate is different depending on the cutting position of the electrode plate, but the material yield is good.

FIGS. 3 (a) and 3 (b) show another embodiment of the invention. FIG. 3 (a) is a front sectional view showing a state in which an electrode original plate is cut, and FIG. ) Is a side view thereof. This is a manufacturing method in which a cut portion is provided when the electrode original plate is cut, and the cutting burr directions of the cut electrode plate are all in the same direction. Adopting this method, in particular, a battery in which a separator or the like is easily damaged by burrs in a cut portion from the electrode body, for example, as a separator material,
In the case of a manganese dioxide / lithium battery or the like which uses a synthetic resin film having a thickness of several tens of microns, an internal short circuit due to breakage of the separator can be prevented by using the electrode plate manufactured by this method.

2 and 3, the diameter of the rotary blade of a pair of rotary blades made of the same material is D ₁ which is the diameter of the rotary blade C which abuts the porous metal body 1b, and the diameter of the rotary blade B which abuts the active material 1a. When the diameter is D ₂ , it is configured such that D ₁ / D ₂ = 1.5 to 3. The fact that D ₁ / D ₂ = 1.5 to 3 was found from the results of various experiments, and it can be applied without any problem as long as it has the dimensions and material configuration of the electrode plate of this type of battery. The results of this type of experiment show that the electrode plate has a thickness of 0.2 to 0.6 mm and a width of 15 to 45 mm, and a porous metal body has a thickness of 0.05 to 0.2 mm and a width of 100 to 100 mm.
At 250 mm, the material is nickel, aluminum, copper, iron, stainless steel, titanium or an alloy thereof, and the active material is the metal oxide, halide, sulfide of manganese dioxide, chromium, iron, cobalt, molybdenum, etc. as described above. It has been found that the same effect can be obtained by using a carbon material such as a substance, a complex oxide thereof, black fluorinated smoke, or activated carbon. The reason why D ₁ / D ₂ = 1.5 to 3 is appropriate is that if the ratio is 1.5 or less, when the rotary blade comes into contact with the metal core body, the metals come into contact with each other, so that the fixing pressure is fixed. However, the phenomenon of slippage occurs and the electrode original plate cannot be cut linearly. If it is 3 or more, the fixing pressure is too large, the metal core is compressed and deformed, and the phenomenon of escape occurs at the contact interface with the rotating blade that causes the phenomenon of surface hardening, and the adhesion force decreases conversely, so the electrode plate It is thought that it will be difficult to cut straight lines.

FIG. 1 shows a manganese dioxide lithium battery constructed to compare the specific effects of the present invention.
Reference numeral 1 shows an electrode original plate in which a positive electrode mixture containing manganese dioxide as a main active material is filled in an electrode plate core body made of a nickel lath plate.
After being cut to a predetermined size by the method of the present invention shown in FIG. Reference numeral 4 is a positive electrode lead plate made of the same material as the core body 1, which is spot-welded to the core body. Negative electrode plate 2
Is made of metallic lithium, and the negative electrode current collector 5 is pressure-bonded to one surface of the negative electrode current collector 5 so as to be located at the outermost periphery of the electrode body when the electrode body A is formed in consideration of reaction efficiency. The separator 3 is made of a microporous film sheet made of polyethylene or polypropylene having a thickness of 25 to 50 μm.
It is cut into a strip shape that is slightly wider than the negative electrode plates 1 and 2.

In this example, a polyethylene microporous membrane having a thickness of 28 μm was used. Next, the positive and negative electrode plates 1 and 2 are spirally wound to form an electrode body A, and the positive electrode lead plate 4 protruding from the electrode body is bent inward, and the negative electrode current collector 5 has its lead portion at the bottom. The electrode body is bent through the insulating plate 7 in the inner diameter direction. After that, insert the electrode plate body into the case 8,
The upper insulating plate 6 is attached, and a step portion that projects in the inner diameter direction is formed on the upper portion of the case 8. The assembly of the battery according to the present invention is completed by injecting an organic electrolytic solution using lithium perchlorate as a solute and using polycarbonate as a solvent, attaching a sealing plate 9 and caulking and sealing the opening of the case 8. .

Here, using the positive electrode plate obtained by the manufacturing method with a pair of rotary blades within the scope of the present invention and the manufacturing method within the range of the comparative example while automatically feeding by the method shown in FIG. Each of the above manganese dioxide / lithium batteries is 5000
Individually manufactured, the number of internal short circuit occurrence of the product of the present invention and the comparative product,
The average value (N = 10) of the discharge capacities when the resistance discharge test of 1000Ω was performed at room temperature and the maximum and minimum actual capacity values were compared. The results are shown in Table 1.

[0016]

[Table 1]

Table 2 shows the results of comparing the lives of the dies in the cutting method of the present invention with or without a spot shown in FIGS. 2 and 3 and the conventional cutting method using the slit blade and the fixed blade. Shown in. As the material of the mold used in the experiment, ordinary high-speed steel was used.

[0018]

[Table 2]

[0019]

As described above, according to the present invention, the electrode original plate can be continuously cut to a desired electrode plate width by the rotary cutting blades at the predetermined intervals, and the mime portion is formed between the rotary blades. By cutting the electrode plate with the setting as provided, it is possible to continuously manufacture an electrode plate in which cutting burrs are formed in the same direction, and especially when cutting the electrode plate of the battery system that adversely affects the cutting burr. It is valid. Also, the life of the mold and the rationalization of the manufacturing process of the battery configured by using the electrode plate in which the other electrode plate made of the active material is wound around the separator using the electrode plate of this type can be achieved. It can be achieved.

[Brief description of drawings]

FIG. 1 is a sectional view of a battery using an electrode plate obtained by the method of the present invention.

FIG. 2 (a) is a sectional view of an essential part of the front surface showing a cut state of an electrode base plate of the present invention. (B) A side view showing a cut state of the electrode base plate of the present invention.

FIG. 3 (a) is a sectional view of a front main part showing a cut state of an electrode original plate according to another method of the present invention. (B) A side view showing a cut state of an electrode original plate according to another method of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Positive electrode plate 1a Positive electrode active material 1b Metal porous body (core body) 2 Negative electrode plate 3 Separator 4 Positive electrode lead plate 5 Negative electrode current collector 6 Upper insulating plate 7 Lower insulating plate 8 Case 9 Sealing plate A Electrode body B Rotating blade C〃 D Mimi part

Claims (4)

[Claims] 1. An electrode for cutting a long electrode plate, in which an active material is attached to a core made of a porous metal, by continuously rubbing a pair of rotary blades having a substantially H-shaped cross section while being fed. A method of manufacturing an electrode plate, wherein a diameter of a rotary blade in contact with the porous metal body is made larger than a diameter of the other rotary blade. 2. A long electrode plate having an active material adhered to a core made of a porous metal material is continuously rubbed with a pair of rotary blades having a substantially H-shaped cross section so as to form a mime portion. A manufacturing method of an electrode plate to be cut, wherein a diameter of a rotary blade in contact with the porous metal body is made larger than a diameter of the other rotary blade. 3. The diameter of the rotary blade which comes into contact with the porous metal body is D ₁ ,
When the diameter of the rotary blade that contacts the active material is D ₂ , D ₁ / D ₂
= 1.5-3.0, The manufacturing method of the electrode plate of Claim 1 or 2. 4. A battery provided with an electrode group in which the electrode plate obtained by the method according to any one of claims 1, 2, and 3 and the other electrode plate made of an active material are spirally wound with a separator interposed therebetween.