JPS6097546A - Manufacturing equipment for battery cathode assemblies - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an apparatus for manufacturing a cathode assembly for a battery using a soft light metal as a cathode active material.

Conventional configurations and their problems Batteries that use light metals such as lithium as negative electrode active materials and non-aqueous electrolytes such as organic electrolytes have high energy density, and with recent advances in electronics, their practical use is progressing. Lithium-free carbon and lithium-manganese dioxide batteries have already come into wide use as backup power sources for electronic watches, calculators, cameras, various communication devices, and various memories. It is thought that the scope of its practical application will continue to expand in the future. Along with this, there is a need for a battery manufacturing apparatus that is highly efficient and suitable for mass production.

The lithium metal used in the cathode of this type of battery is a very soft, sticky, and non-slip material, which imposes major restrictions on battery assembly and requires highly productive manufacturing equipment. ing.

Particularly in the case of cylindrical batteries having a spiral electrode group, conventionally, a separator made of a continuous long strip of polypropylene nonwoven fabric is intermittently fed out, and lithium sheets cut to predetermined dimensions are placed on top of the separator at intervals. At the same time, the other separator was supplied, and the polypropylene nonwoven fabric separators were integrally pressed and bonded to both sides of the lithium sheet by passing the lithium sheet through a pair of rolls. However, as mentioned above, lithium is soft and easily adheres to other objects, so when transferring it, it cannot be transferred reliably to the specified position, and the lithium sheet may protrude beyond the separator or the periphery of the lithium sheet may be bent. was. Further, when pressure bonding is performed using a roll, lithium protrudes from the separator due to non-uniform thickness of lithium, which causes an internal short circuit when forming a battery.

Purpose of the Invention In view of the above-mentioned drawbacks, the present invention provides a highly productive and reliable b# assembly apparatus that simplifies the transfer of lithium sheet separators and can continuously mass-produce cathode assemblies. This is what we provide.

Structure of the Invention The present invention provides a continuous cathode assembly in which lithium sheets are arranged at regular intervals on a long separator, and the long lithium sheet is cut or slit in a predetermined dimension. After slackening the separator between them to make the moving speed of lithium and the separator the same, stacking them so that the cut in the lithium matches the slack position of the separator, the lithium and the separator are joined by partial crimping, and the cut in the lithium [7] This is characterized by arranging lithium at equal intervals on the separator by stretching the slack of the separator.

Description of examples Hereinafter, the present invention will be explained in detail with reference to Examples.

FIG. 1 shows an assembly 1 of a secondary lithium cathode and a separator constituting a spiral electrode group. This cathode assembly 1 and 2
, a lithium sort 2, a nickel current collector 3 embedded in its end side, and a separator 4-1.4 made of a polypropylene nonwoven fabric crimped on both sides of the lithium sheet 2.
-2.

FIG. 2 is a schematic diagram of a manufacturing apparatus for this cathode assembly. The long lithium sheet 2' is cut to a predetermined size by the cutter part 5, and the current collector 3 is crimped at a fixed position by the current collector supply crimping part 6. Lithium A'-se/: Lithium is placed on the separator 4-1 at equal intervals at the lathe partial pressure bonding and cutting section 7. The other separator 4 at the crimp part 8
-2 are overlapped and passed through a pair of rolls to bond and bond the lithium sheet and the separator together. The continuous cathode assembly is wound up in a winding section 9.

The main parts will be explained in detail below.

FIG. 3 is a sectional view of the transport drum 15 for the lithium sheet 2'. The lithium sheet 2' is held on the drum by suction negative pressure acting on holes provided in the drum. Grooves are provided in two places on the drum surface, and urethane rope 1Q is inserted inside.
is passing through.

Figure 4 shows a part of the cutter, and the felt roll 11
is impregnated with a mold release agent, and the mold release agent is applied to the cutting edge of the canter 12. The cutter blade is straight as shown in the figure, but even if the lithium is pushed by the cutter 12 in the groove where the urethane rope is located in Figure 3, it escapes to the urethane rope side and is not cut. Make a cut in.

FIG. 5 shows the partial crimping and cutting of the lithium separator, which is a feature of the present invention. It is rolled into the winding drum 14 by a predetermined amount. The lithium is transferred to the urethane rope 1o in the transport tram 16 so that the cut position of the lithium processed in the previous step matches the separator winding position.

There are several convex portions 16 on the surface of the winding drum 14, and by passing the lithium and the separator through a partial press roll 17, the lithium and the separator are partially press-bonded at these convex portions. The outer periphery of one of the pair of cutting rolls 18 is processed so that only a portion of the partially crimped lithium is sandwiched therein, and the lithium is sandwiched at this portion, and the lithium is transferred at a faster speed than the moving speed in the previous process. Pull the lithium sheet apart at the cut point.

FIG. 6 shows the winding pin 13 provided on the winding drum 14.
The cylindrical cam 19 gives the winding pin 13 back and forth movements (1) and (3), and the plate cam 2
0, the turning motions (2) and (4) are applied via the pin 21. The separator 4-1 guided to the outer circumferential surface of the winding drum 14 is rolled up by the winding pin 13 by the operation shown in (1) in the figure by the cylindrical cam 19, moved onto the outer circumference of the drum 14, and then moved by the plate cam 20. By the operation (2), the separator 4-1 is rolled into the winding drum 14. In this state, separator 4
- 1 is overlaid with lithium, then partial pressure roll 17
Partial crimping is achieved by passing it through. Although the separator wound up by the cutting roll 18 is stretched, it is moved back by the operations (3) and (4) or a combination thereof so as not to interfere with each other.

Figure 7 briefly shows this crimp principle.
, 2' is preliminarily slackened in the previous step, and lithium 2 is layered on the separator at the same speed, partially crimped and fixed, and then separated at a speed with a pitch length of L.

FIG. 8 shows the crimping part, where lithium 2 is placed on the separator 4-1 at equal intervals, and the other separator 4 is
The lithium 2 and the separator 4-1, 4-2 are bonded by pressure through a pair of pressure rolls 22 so that the lithium 2 and the separators 4-1 and 4-2 are overlapped.

After processing a continuous cathode assembly in this way, a single cathode assembly is completed by cutting the separator at a portion that does not come into contact with lithium.

Effects of the Invention According to the present invention, lithium can be continuously supplied onto the separator, and while the conventional processing speed was limited to 16 pieces/minute, it has become possible to process 120 pieces/minute. . In addition, by partially press-bonding the lithium-separator and then press-bonding it with a roll, it is possible to prevent lithium from coming out of the separator due to uneven thickness of lithium, and a highly reliable cathode assembly can be manufactured. .

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a battery cathode assembly, FIG. 2 is a schematic diagram of a cathode assembly manufacturing apparatus in an embodiment of the present invention, FIG. 3 is a sectional view of a lithium conveying drum, and FIG. 4 is a cutter assembly. FIG. 5 is a perspective view of the lithium-separator partial crimping and cutting part, which is a feature of the present invention. FIG. 6 is an explanatory diagram of the operation of the winding pin provided on the winding drum. Principle diagram that simply shows the crimping of sheets and separators, No. 8
The figure is a schematic diagram of the crimping section. 1... Cathode assembly, 2... Lithium sheet, 2'... Long lithium sheet, 3...
... Current collector, 4-1.4-2 ... Separator,
6... Cutter part, 6... Current collector supply crimping part, 7... Lithium separator partial crimping, cutting part, β... Crimp part, 9- ... Winding section, 1
0... Urethane rope, 11... Felt roll, 12... Cup p-113...,
・Retracting pin, 14...Retracting drum, 16・
...Lithium conveyance drum, 16... Convex portion on the outer circumferential surface of the winding drum, 17... Partial pressure bonding rope 18-... Pressure roll, 19... Cylindrical cam, 20... Plate cam, 21... Pin, 22...
...Crimp roll. Name of agent: Patent attorney Toshio Nakao and 1 other person 2nd
Figure 3 @ Figure 4 Figure 6

Claims (1)

[Claims] A device for cutting or incising a material made of soft light metal into a fixed size on one side of a sheet-like separator, a device for slackening the separator between the cathodes, and a crimping device for stacking and bonding the separator and the cathode active material. The method is characterized in that the cathode active material and the separator are piled up at the same speed by making the separator slack, and after pressure bonding, the cathode active material is arranged on the separator at equal intervals by stretching out the slack of the separator. Manufacturing equipment for battery cathode assemblies.