JP2003001585A - Blade for gang cutter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a blade which can lessen burrs of a metal foil generated at the time of cutting out a sheet-like electrode. SOLUTION: On an upper axis of rotation 7, which is furnished with an upper blade 1, an acute-angled blade 5 having an acute-angled blade edge part 5a which projects in an outward direction of perimeter side of the upper blade 1, so that the upper blade 1 and a lower blade 2 may be touched, is attached. A blade-edge angle of the acute-angled blade is set to angles of 15 and 45 degrees, and a size of the acute-angled blade edge part 5a is made smaller than a thickness of the sheet-like electrode, and larger than a thickness which added one side of an active material layer and the metal foil.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blade for a gang cutter for continuously cutting a sheet electrode used in a lithium ion battery with a predetermined width.

[0002]

2. Description of the Related Art Generally, a sheet-like electrode is used as an electrode for a lithium ion battery, in which a positive or negative electrode active material of about 75 μm is coated on both sides of a copper or aluminum metal foil of about 15 μm. ing.

These sheet-like electrodes are produced by applying a positive electrode or negative electrode active material on both sides of a wide metal foil and drying. Then, as shown in FIG. 4, slits are formed in accordance with the size of the battery to be used and cut into a predetermined width, and then wound on one or a plurality of rolls.

Conventionally, for cutting a sheet electrode, as shown in FIG. 3, a pair of upper blade 1 and lower blade 2 which face each other, and a spring 6 are used.
A gang cutter (or sometimes referred to as a contact pressure type gang cutter) that meshes in a state where a contact pressure is applied and continuously cuts is used.

That is, as shown in FIG. 3, the gang cutter is composed of a pair of annular rotary blades called an upper blade 1 and a lower blade 2. Then, generally, the cutting edges of the upper blade 1 and the lower blade 2 have a cross-sectional shape of a substantially right angle, and the upper blade 1 and the lower blade 2 mesh with each other at the time of cutting. A contact pressure is applied to the lower blade 2 by a spring 6 and the upper blade 1 is used in a sliding contact state.

Therefore, the upper blade 1 and the lower blade 2 of the gang cutter rotate in opposite directions while being in sliding contact with each other, and successively cut the wide sheet electrode into a predetermined width. (Fig. 4).

[0007]

However, when the sheet-like electrode is cut by using the conventional gang cutter as shown in FIG. 3, the burrs are formed on the metal foil portion existing in the central portion. It is recognized that there is a problem that is likely to occur.

If there is a burr on the metal foil of the sheet-shaped electrode, it may cause an assembly failure when assembling the battery from the electrode plate, or may damage the separator to cause a short circuit with the counter electrode. Is known to affect.

An object of the present invention is to eliminate the above-mentioned problems, and to provide a blade for a gang cutter, which can reduce the burr of the metal foil that occurs when the sheet electrode is cut.

[0010]

In order to solve the above-mentioned problems, the present invention is characterized by providing an acute-angled blade as a blade for a gang cutter in addition to an upper blade and a lower blade.

That is, the first invention has an upper blade and a lower blade which are attached to a pair of parallel rotating shafts and cut the sheet-like electrode while rotating and have an annular cross section. In a blade for a gang cutter, on one of the rotating shafts to which the upper blade or the lower blade is attached,
A disk-shaped acute-angled blade is attached so as to be in contact with the upper blade and the lower blade, and the acute-angled blade protrudes outward from the outer peripheral surface of the upper blade or the lower blade attached to the same rotating shaft. It is characterized by having a sharp-edged blade tip.

According to a second aspect of the invention, the dimension of the tip portion of the acute-angled blade is smaller than the thickness of the sheet-shaped electrode and larger than the thickness of one active material layer of the sheet-shaped electrode and a metal foil. According to a third aspect of the invention, the acute angle blade has a blade edge angle of 15 degrees to 45 degrees.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to FIG.
It will be described in detail using 2. FIG. 1 is a schematic view of a main part at the time of cutting using a blade for a gang cutter according to the present invention, and FIG. 2 is a gang cutter according to the present invention.
It is a schematic diagram showing the state where the upper blade and the lower blade meshed to the deepest.

The gang cutter according to the present invention is shown in FIG.
As shown in FIG. 2, in addition to the conventional upper blade 1, an acute angle blade 5 is used to cut the sheet electrode 9. And
The cutting edges of the upper blade 1 and the lower blade 2 are such that the upper blade 1 and the lower blade 2 mesh with each other when the sheet-shaped electrode 9 is cut, and the sharp blade 5 and the lower blade 2
And has a structure having an appropriate wrap amount 12.

The upper blade 1 and the lower blade 2 are rotary blades each having a circular cross section with a substantially right angle, and are attached to the upper rotary shaft 7 or the lower rotary shaft 8, respectively.

On the other hand, the sharp-edged blade 5 is disk-shaped and has a sharp sharp-edged blade tip portion 5a having a cutting edge angle of 15 to 45 degrees.
The sharp-edged blade tip portion 5a has a structure protruding outward from the outer peripheral surface of the upper blade 1 (FIG. 1). And a sharp blade 5
Is attached to the upper rotary shaft 7 at a position in contact with the upper blade 1 and the lower blade 2.

Then, the upper blade 1 and the acute-angled blade 5 which are in contact with each other
While applying a contact pressure between the lower blade 2 and the lower blade 2 by means of the spring 6 provided on the collar A3, the lower blade 2 and the annular peripheral edge portion are rotating in opposite directions in sliding contact with each other (FIG. 4). The wide sheet electrode 9 is continuously cut.

[0018]

EXAMPLE As an example, as shown in FIG.
An experiment was carried out by using a sharp-edged blade 5 having a disk shape of 13 at 15 degrees, and changing the dimensions of the sharp-edged blade tip portion 5a as shown below.

In the following experiment, a sheet-shaped electrode 9 for negative electrode having 75 μm on each of the active material layers 11 on both sides, 10 μm on the central copper foil 10 and having a total thickness of 160 μm was used. 12 was adjusted to 250 μm and experimented.

(Example 1) The dimension of the sharp-edged blade tip portion 5a is
Experiments were carried out using a gang cutter having a sharp edge 5 of 50 μm. That is, the experiment was performed by making the dimension of the sharp-edged blade tip portion 5a shorter than the thickness of the active material layer 11 on the upper surface of the sheet electrode 9.

(Embodiment 2) The dimension of the acute angle blade tip portion 5a is
Experiments were carried out using a gang cutter having a 100 μm sharp-edged blade 5. That is, an experiment was conducted by making the dimension of the sharp-edged blade tip portion 5a shorter than the thickness of the sheet electrode 9 and longer than the dimension of one active material layer 11 of the sheet electrode 9 and the metal foil 10.

(Embodiment 3) The dimension of the sharp-edged blade tip portion 5a is
Experiments were carried out using a gang cutter having a sharp blade 5 of 200 μm. That is, the dimension of the acute angle blade tip portion 5a,
The experiment was performed by making the sheet electrode 9 longer than the entire thickness dimension.

(Comparative Example) As a comparative example, an experiment was carried out using a conventional gang cutter having a structure without the acute angle blade 5 (FIG. 3).

Table 1 shows the results of observing the occurrence of burrs on the metal foil 10 by cutting the sheet electrode 9 using the above-mentioned four types of gang cutters. It can be seen from Table 1 that the gang cutter according to the present invention is excellent in that the metal foil 10 has less burrs.

[0025]

[Table 1]

In the above-mentioned examples, the results of the experiment using the sheet electrode for the negative electrode having the copper metal foil 10 are shown.
The same good result was obtained when the experiment was conducted using the positive electrode sheet-shaped electrode having the aluminum metal foil 10.

Similar good results were obtained even when the disk-shaped acute-angle blade 5 having a blade angle of 15 to 45 degrees was used. In addition, in this embodiment, the lap amount 12 was adjusted to 250 μm for the experiment, but the lap amount 12 is 100 to 500 μm.
Also in m, the same good result was shown.

[0028]

As described above, when the blade for a gang cutter according to the present invention is used, it is possible to reduce the burr of the metal foil generated during the cutting of the sheet-like electrode used in the lithium ion battery, which is industrially excellent. It is a thing.

[0029]

[Brief description of drawings]

FIG. 1 is a schematic view of a main part at the time of cutting using a blade for a gang cutter according to the present invention.

FIG. 2 is a schematic view showing a state in which the upper blade and the lower blade mesh with each other most deeply in the gang cutter according to the present invention.

FIG. 3 is a schematic view showing a state in which an upper blade and a lower blade are deepest meshed with each other in a conventional gang cutter.

FIG. 4 is a schematic view of a step of cutting a sheet-like electrode using a gang cutter.

[Explanation of symbols]

1: Upper blade, 2: Lower blade, 3: Color A, 4: Color B,
5: acute-angled blade, 5a: acute-angled blade tip portion, 6: spring, 7: upper rotating shaft, 8: lower rotating shaft, 9: sheet electrode, 10:
Metal foil, 11: Active material layer, 12: Lapping amount 13: Cutting edge angle

Claims (3)

[Claims] 1. A blade for a gang cutter, which is attached to a pair of parallel rotary shafts and cuts a sheet-like electrode while rotating, and which has an upper blade and a lower blade each having an annular cross section and having an annular shape. , One of the rotary shafts to which the upper blade or the lower blade is attached, a disk-shaped acute-angled blade is attached so as to contact the upper blade and the lower blade, and the acute-angled blades have the same rotary axis. A blade for a gang cutter, characterized in that it has an acute-angled blade tip portion projecting outward from the outer peripheral surface of the upper blade or the lower blade attached to the. 2. The dimension of the tip of the acute-angled blade is smaller than the thickness of the sheet-like electrode, and is larger than the thickness of one of the sheet-like electrodes plus the active material layer and the metal foil. A blade for a gang cutter according to claim 1. 3. The blade for a gang cutter according to claim 1, wherein the acute angle blade has a cutting edge angle of 15 degrees to 45 degrees.