JP2004047324A - Formation and mounting method of lithium flake, and manufacturing method of battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To cut out a lithium flake from a band material formed of lithium to mount the lithium flake to a mounting body with high positioning accuracy. <P>SOLUTION: A line 200 for housing the lithium flake 5 in a negative electrode side case 30 carries out, as main processes, the following processes: a process for making a carrier film 60 and the band material 62 mutually adjacent to each other while feeding them so as to face their principal surfaces to each other, and thereafter pressingly bonding the band material 62 to the carrier film 60 by applying pressure to both of them from the upper and lower directions of the facing surfaces; a process for manufacturing the lithium flake 5 by cutting the band material 62 that is compression bonded to the surface of the carrier film 60 into a predetermined shape without severing the carrier film 60; and a process for housing the lithium flake 5 in the negative electrode side case 30 while peeling it off the carrier film 60. The above processes are repeated in that order while continuously or intermittently feeding the band material 62 and the carrier film 60 from the left side toward the right side in Figure 6. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for producing a lithium flake from a lithium metal strip, attaching the lithium flake to an object to be attached, and a method for manufacturing a battery employing the method.
[0002]
[Prior art]
2. Description of the Related Art In recent years, a demand for a plate-type battery for a power source for an IC card, a card-type calculator, and the like has been rapidly increasing. As a typical example, a lithium primary battery using lithium metal as an anode (battery negative electrode) is known. An example is shown in FIG. In FIG. 1, the upper diagram is a perspective view, and the lower diagram is a cross section taken along the line AA ′. The plate-type battery 100 configured as a lithium primary battery has a structure in which a negative electrode active material 5 and a positive electrode active material 6 separated by a separator 9 are sandwiched between two metal current collector plates 7 and 8. have. Such a plate-type battery 100 is manufactured by assembling the electrode active materials 5 and 6, the separator 9, the current collectors 7 and 8, and the resin-made frame-shaped exterior materials 1 and 3 with each other.
[0003]
On the other hand, conventionally, as a method of obtaining a sheet piece by cutting a sheet-shaped strip into a predetermined shape, there is a method as shown in FIG. The sheet band 14 wound in advance on the reel 11 is fed to a conveyor device 15 in which a pair of endless belts 12 and 13 are arranged in parallel so that their main surfaces are in surface contact with each other. 16 and are sequentially supplied. The belt 14 guided to the opposing surfaces of the endless belts 12 and 13 is conveyed while the traveling direction is regulated by guide members 17, 18 and 19 arranged along both ends of the belt 14 in the width direction WL. It is fed toward the cutting blades 40 and 41 provided on the outlet side of the device 15. The strip 14 transported to the cutting blades 40 and 41 is cut into a predetermined shape. The sheet piece 42 produced by the cutting is sucked and conveyed by the vacuum pad 44 and attached to the attached body 43.
[0004]
This method is also suitable for manufacturing the above-described plate-type battery 100. That is, the lithium metal serving as the negative electrode active material is processed into a belt shape in advance and wound on a reel, and then the lithium band material is cut into the shape required for the plate-type battery 100 one after another. Then, the obtained lithium flakes 5 are attached to an attached body that becomes the plate-type battery 100.
[0005]
[Problems to be solved by the invention]
However, when the strip is made of lithium metal, the situation is significantly different from that of a resin or metal that is usually considered. Since lithium is a very soft solid at room temperature, transport and cutting are very difficult. While the guide member has been described as regulating the traveling direction of the strip at the time of transport, the guide member is made of a lithium metal strip (hereinafter, also simply referred to as a lithium strip or a strip) because it is thin and soft. Deformation occurs easily when contacting the member, and the effect of regulating the traveling direction is hardly obtained. Further, the lithium metal adheres to the cutting blade, which hinders stable cutting. Further, it is difficult to handle the manufactured lithium flakes, so that the positions of the lithium flakes to be attached to the attached body tend to vary. At the manufacturing site of a plate-type battery, such difficulties hinder improvement in yield and productivity.
[0006]
Therefore, the first object of the present invention is to provide a method for cutting a lithium flake from a lithium metal strip with high shape accuracy and mounting the lithium flake to a mounting body with high positioning accuracy. I do. By adopting this method, it is possible to cut out a lithium flake that is to be an electrode active material from a lithium metal strip with high shape accuracy, and attach the lithium flake to an object to be a battery with high positioning accuracy. A second object is to provide a method for manufacturing a battery.
[0007]
[Means for Solving the Problems and Functions / Effects]
The present invention for solving the above problems is a method for producing a lithium flake from a lithium metal strip, and attaching the lithium flake to an attached body,
A step of bringing the band-shaped resin carrier film and the band material closer to each other while sending them so that the main surfaces thereof face each other, and then pressing the band material to the carrier film by applying pressure to the carrier film from above and below the facing surface. When,
A step of producing a lithium flake by cutting the band material pressed on the carrier film into a predetermined shape without dividing the carrier film,
Removing the lithium flake from the carrier film and attaching the lithium flake to the object to be attached.
[0008]
In the method of the present invention, the lithium band material is pressure-bonded to the carrier film by positively utilizing the adhesiveness of lithium, which was only an obstacle in the conventional method, and the cutting and mounting steps are performed. . After the band is pressed and fixed to the carrier film, the traveling direction of the band is regulated by regulating the traveling direction of the carrier film. That is, it is not necessary to bring the strip into contact with the feeding means and the guide member. This can prevent the strip from being deformed or sticking to other members. In addition, since the carrier film is not divided at the time of cutting the strip, there is little possibility that the lithium flakes produced by the cutting will be misaligned. Further, since the strip is fixed to the carrier film, adhesion to the cutting blade is also suppressed. In addition, it is possible to use the carrier film as a reference for positioning, and it can be expected that the positioning accuracy when the lithium flake is attached to the object to be attached is improved. Further, since the adhesive is not used when the band material is carried on the carrier film, there is no possibility that the adhesive is mixed into the attached body which is a product.
[0009]
As the carrier film, one having at least one main surface subjected to a roughening treatment is used, and a lithium band material is preferably bonded to the principal surface having the roughened surface. With this configuration, an effect (anchor effect) of the lithium metal entering the void formed by the surface roughening process can be expected, and the lithium band can be more securely pressed against the carrier film.
[0010]
In addition, the method for manufacturing a battery according to the present invention that solves the problem includes:
A negative electrode case having a concave portion for accommodating a negative electrode active material is formed by bonding a negative electrode current collector plate to the negative electrode side frame-shaped exterior material so as to cover one opening of the negative electrode side frame-shaped exterior material made of a resin sheet. On the other hand, the band-shaped resin carrier film and the lithium metal band are brought close to each other while being sent out such that the main surfaces thereof face each other, and then the band is applied by applying pressure to the both from the vertical direction of the facing surface. Is pressed into a carrier film, and the band material pressed on the carrier film is cut into a predetermined shape without dividing the carrier film to produce a lithium flake, and the lithium flake is housed in the negative electrode case while being peeled off from the carrier film. A negative electrode forming step;
A separator forming step of attaching the separator to the negative electrode case so as to cover the lithium flakes,
On the separator, a positive electrode active material, a positive electrode forming step of arranging a positive electrode side frame-shaped exterior material forming a pair with the negative electrode case and a positive electrode case made of a positive electrode current collector plate,
It is characterized by including.
[0011]
In the method of manufacturing a battery according to the present invention, it is recognized that the above-described method of producing and attaching a lithium flake is inseparably integrated into a battery manufacturing process as one of the most important steps in battery assembly. Therefore, the battery manufacturing method of the present invention can fully enjoy the significant effects of the above-described method. Specifically, it is difficult for the lithium strip to be deformed during transportation, stable production of lithium flakes of the same shape is possible, and when the lithium flakes are attached (accommodated) to an object to be mounted, which is in the process of manufacturing a battery. It is expected that the yield and the production efficiency can be improved because of the expectation of the improvement of the positioning accuracy of the semiconductor device.
[0012]
In a preferred aspect, the negative electrode case is configured as a multiple-piece case assembly in which a plurality of concave portions are formed in the in-plane direction of the negative-side frame-shaped exterior material. After doing so, the position where the lithium flakes are transferred from the carrier film to the negative electrode case is adjusted in synchronization with the movement / stop of the carrier film and the band material so that each recess moves sequentially. Move / stop, and all the recesses individually contain lithium flakes.
[0013]
As described above, the supply of the lithium band material and the carrier film is performed one after another, and accordingly, lithium flakes are successively produced. As described above, if the multiple-piece case assembly accommodating the lithium flakes is moved / stopped in synchronization with the continuous production of the lithium flakes, high throughput in this step can be expected. Movement / stop of the multiple case assembly can be easily performed by, for example, an xy stage driven by a servo actuator.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
FIG. 1 shows the structure of the plate-type battery 100 as described above. A plate-type battery 100, which is an example of a lithium primary battery, is manufactured by assembling electrode active materials 5, 6, a separator 9, current collectors 7, 8, and frame-shaped exterior materials 1, 3 (hereinafter, referred to as a window frame) with each other. Is done. FIG. 2 is a cross-sectional view schematically illustrating one embodiment of the manufacturing method.
[0015]
Before describing the manufacturing method, components of the plate-type battery 100 will be described.
The window frames 1 and 3 are made of a thermoplastic resin such as polyethylene (PE), polypropylene (PP), or polyethylene terephthalate (PET), and are provided on both sides with ethylene vinyl acetate (EVA) and ethylene methacrylic acid. A hot-melt adhesive layer such as a copolymer (EMAA) is formed. In this embodiment, the window frames 1 and 3 use a resin sheet having a three-layer structure in which biaxially oriented polypropylene (OPP) is sandwiched between ethylene / methacrylic acid copolymers. The thickness of the window frames 1 and 3 is, for example, 90 to 150 μm. Adhesion between the window frames 1 and 3 and the current collectors 7 and 8 and adhesion between the window frames 1 and 3 and the separator 9 are performed via the adhesive layer.
[0016]
As the negative electrode active material 5, a lithium flake made of lithium metal can be used. Lithium metal means lithium or a lithium alloy. The thickness of the lithium flake is, for example, 90 to 150 μm. This thickness is also the thickness of a lithium strip 62 described later. As the positive electrode active material 6, for example, a slurry composed of 60 to 70% by mass of manganese dioxide powder, 5 to 10% by mass of carbon, and 25 to 35% by mass of an electrolyte can be suitably used. As the electrolyte, an organic solvent such as ethylene carbonate or propylene carbonate may be added to a lithium triflate salt (LiCF ₃ SO ₃ ) Can be used. The separator 9 is a thin film-shaped member that allows the passage of ions. Specifically, the separator 9 is a sheet piece having a porous and multilayer structure made of a resin such as polyethylene or polypropylene, and has a thickness of, for example, 30 to 60 μm. The current collectors 7 and 8 are copper plates.
[0017]
Next, a manufacturing process of the plate-type battery 100 will be described.
As shown in FIG. 2, first, the current collector 7 on the negative electrode side is brought into surface contact so as to close one opening of the window frame 1, and the adhesive layer of the window frame 1 is melted by an ultrasonic welding method or a heat welding method. Then, the current collector 7 is adhered to the window frame 1. Thereby, the negative electrode case 30 having the concave portion 2 for accommodating the lithium flake 5 is manufactured (2-1). Next, the lithium flake 5 is accommodated in the recess 2 of the negative electrode case 30 (2-2). Then, the separator 9 is placed so that its outer peripheral edge is in surface contact with the opening peripheral edge of the window frame 1 (2-3). Then, the separator 9 is adhered to the window frame 1 by melting only the adhesive layer constituting the window frame 1 without dissolving the separator 9. As a result, the lithium flakes 5 are covered with the separator 9.
[0018]
Next, the slurry which becomes the positive electrode active material 6 is thick-film printed on the main surface of the separator 9 by a screen printing method (2-4). Then, the positive electrode case 31 paired with the negative electrode case 30 is put on the positive electrode active material 6 printed on the separator 9 (2-5). The positive electrode case 31 includes the window frame 3 and the current collecting plate 8, and is manufactured by the same method as the negative electrode case 30. Then, the ultrasonic horn 52 is brought into contact with the current collecting plate 8 from above to melt the adhesive layers of the window frames 1 and 3, thereby forming a gap between the negative side window frame 1 and the positive side window frame 3. Seal. This ultrasonic welding step is performed while sucking the air G or in a vacuum so that the inside of the completed plate battery 100 is kept in a vacuum (2-6). Thus, the plate-type battery 100 is manufactured. In addition, in this specification, the vacuum means a state in which the pressure is lower than the atmospheric pressure.
[0019]
As shown in FIG. 5, the negative electrode case 30 can be configured as a multi-piece case assembly 33 in which a plurality of concave portions 2 are formed in the in-plane direction of the window frame 1 constituting the negative electrode case 30. This is the same for the positive electrode case 31. In order to manufacture the multiple case assembly 33, first, as shown in FIG. 3, a resin sheet 1 'serving as the window frame 1 is fixed to a rectangular frame 20. In such a frame 20, a through hole 21 and a notch 21a serving as alignment marks of the multiple case assembly 33 are formed.
[0020]
After the resin sheet 1 ′ is fixed to the frame 20, a predetermined portion of the resin sheet 1 ′ is removed to form a through portion 2 ′ and a through portion 24 as shown in FIG. Then, as shown in FIG. 5, the current collector plate 7 is adhered to the window frame 1 so as to close one opening of the penetrating portion 2 ′, thereby forming a plurality of concave portions 2 based on the penetrating portion 2 ′. The take case assembly 33 is completed. The power take-out portion 7a of the current collector 7 is exposed in the through portion 24. Since the relative positional relationship between the through portion 2 ′ and the above-described through hole 21 (or notch 21a) is clear, it is easy to position the negative electrode case 30 (positive electrode case 31) in each step shown in FIG. Can be done.
[0021]
The step of individually storing the lithium flakes 5 in the recess 2 of the negative electrode case 30 manufactured as described above (see FIG. 2 (2-2)) will be described. This step is an essential part of the present invention. Specifically, the lithium flake 5 is prepared from the lithium metal band 62, and the lithium flake 5 is attached to the negative electrode case 30 (attached body). It can be said that the method. FIG. 6 schematically shows a line for performing the method.
[0022]
In the line 200 for accommodating the lithium flakes 5 in the negative electrode case 30, the carrier film 60 and the band material 62 are brought closer to each other while being sent out such that the main surfaces are opposed to each other. Pressurizing the strip 62 to the carrier film 60 by applying pressure, and cutting the strip 62 pressed on the carrier film 60 into a predetermined shape without dividing the carrier film 60 to produce the lithium flakes 5. The main step is to perform a step of removing the lithium flakes 5 from the carrier film 60 and storing the lithium flakes 5 in the negative electrode case 30. Specifically, the above steps are repeatedly performed in the order described above while continuously or intermittently sending out the band material 62 and the carrier film 60 from the left side to the right side in the figure.
[0023]
Desirably, the carrier film 60 and the band material 62 are fed so that both of them repeatedly move and stop, and at the time of the stop, the above-described steps are performed. If each step is performed in a state where the movement is completely stopped, the possibility of occurrence of an error in pressure bonding, an error in cutting, an error in transport, or the like is reduced.
[0024]
The step of pressing the band 62 to the carrier film 60 will be described in detail.
The carrier film 60 is a belt-shaped resin film whose thickness is adjusted to 50 to 100 μm. Although the type of the resin is not particularly limited, a PET resin is used in the present embodiment. One end of the carrier film 60 is fixed to the carrier film supply reel 61 described above, and the other end is fixed to the collection reel 64 in advance. The rotation of the carrier film supply reel 61 and the collection reel 64 drives the supply reel 61 for the carrier film. Are sent out sequentially. The transporting force is applied to the lithium strip 62 by a feed roller 75 or the like, and the lithium strip 62 is supplied from the lithium strip supply reel 63 disposed vertically below the carrier film 60 so as to approach the carrier film 60. Of course, the feed speeds of both are made to match.
[0025]
After sufficiently bringing the carrier film 60 and the band material 62 close to each other, the crimping position P shown in FIG. ₁ Pressure is applied from the upper and lower sides of the opposing surfaces by the press devices 70 and 71 arranged at the (first position). The pressure at this time may be adjusted to a strength at which the strip 62 is securely carried on the carrier film 60. It is preferable to use a carrier film 60 having at least one principal surface subjected to a roughening treatment. When the band material 62 is crimped to the main surface that has been subjected to the surface roughening treatment, more reliable crimping can be realized by the anchor effect. The surface storm can be performed by a known blasting process. For reference, when the arithmetic mean roughness Ra of the main surface of the blasted PET resin carrier film 60 was examined, a result of 0.64 μm was obtained. On the other hand, Ra without the blast treatment was 0.036 μm. The surface roughness of the carrier film 60 is preferably adjusted so that the strips 5 are not easily peeled off while the strip 62 is securely pressed. The arithmetic mean roughness Ra means a value measured by a method specified in JIS: B0601 (1994).
[0026]
The carrier film 60 is wider than the band material 62, does not protrude from the carrier film 60 in the width direction WL, and has a non-adhesion region 60a on at least one side of the carrier film 60 in the width direction WL. It is preferable to arrange the strip 62 in such a manner (see FIG. 9) and to guide the edge of the non-adhesion area 60a by the guide members 76, 76 and the like. In this way, the strip 62 does not contact the guide members 76 and is not deformed. In the present embodiment, the width of the carrier film 60 is adjusted so that the non-adhesion regions 60a are formed on both sides in the width direction. Note that the width direction of the strip 62 and the width direction of the carrier film 60 are indicated by the same symbol WL, and in FIG. In addition, the non-adhesive region 60a is a region where the band material 62 is not pressed.
[0027]
Next, the step of cutting the strip 62 will be described in detail.
The cutting of the strip 62 is performed at the crimping position P ₁ Cutting position P downstream ₂ (2nd position). Cutting position P ₂ , A cutting device 73 and a cutting table 72 are arranged. As shown in FIG. 7, in order to cut the strip 62 to obtain the rectangular lithium flakes 5, in this embodiment, a cutting device 73 in which two sets of parallel cutting blades 73a and 73b are fixed to a lifting base 73d. Is adopted. The cutting blades 73a and 73b of this form are preferable because they are less expensive than square cutting blades. Further, since the cutting blades 73a and 73b do not directly contact the cutting table 72, wear of both of them hardly progresses.
[0028]
As shown in FIG. 9, when cutting the strip 62, the carrier film side alignment mark 80 used when attaching the lithium flake 5 to the negative electrode case 30 may be formed in the non-adhesive region 60 a of the carrier film 60 at the same time. . In this way, the relative positional relationship between the alignment mark 80 and the lithium flake 5 is always constant, even if the pressure-bonding position of the strip 62 on the carrier film 60 varies. Therefore, the positioning accuracy of the lithium flake 5 using the positioning mark 80 is extremely high.
[0029]
Such a carrier film side alignment mark 80 can be a through hole 80 penetrating the carrier film 60 in the thickness direction. Since it is only necessary to ensure the function as an alignment mark, a notch may be formed at the edge of the carrier film 60 or a score line may be formed on the surface. However, by forming the through-hole, mechanical positioning can be performed with a positioning pin or the like without using a camera or the like, which can contribute to a reduction in equipment cost.
[0030]
In order to form the lithium flake 5 and the alignment mark 80 at the same time, the following may be performed. That is, the cutting blades 73a and 73b for producing lithium flakes and the punch 73c for forming a through hole are fixed to the elevating base 73d, and the elevating base 73d moves to a position where the punch 73c penetrates the carrier film 60. Also, the relative height of the cutting blades 73a, 73b and the punch 73c is adjusted so that the cutting blades 73a, 73b do not penetrate the carrier film 60. FIG. 8 is a schematic side view of the cutting device 73 whose height has been adjusted as described above. In the present embodiment, the difference between the height of the cutting blades 73a and 73b with respect to the elevating base 73d and the height of the punch 73c is adjusted to be substantially equal to the thickness Dc of the carrier film 60. This is important when cutting the band 62 without dividing the carrier film 60. By adjusting the height in this manner, when the punch 73c penetrates the carrier film 60, the effect that the tips of the cutting blades 73a and 73b cut the lithium flake 5 into the carrier film 60 can be expected.
[0031]
As described above, the carrier film 60 has one end fixed to the supply reel 61 and the other end fixed to the collection reel 64 in advance, and is sent out from the supply reel 61 by rotating the supply reel 61 and the collection reel 64. After doing so, in the step of producing the lithium flake 5, the strip 62 is cut so as to be divided into the lithium flake 5 and the remaining strip 50, and the carrier film 60 is formed on the remaining strip 50 (see FIG. 9). Together with the collecting reel 64 for collection. This also prevents the chips from becoming bulky. The strip remaining portion 50 can be separated from the supply reel 64 and reused.
[0032]
Further, by applying an organic solvent, such as ethylene carbonate or propylene carbonate, used for the plate-type battery 100 to the cutting blades 73a and 73b in advance, it is possible to prevent the strip 62 from sticking to the cutting blades 73a and 73b. Is done.
[0033]
Next, the step of accommodating the lithium flakes 5 in the negative electrode case 30 will be described in detail.
As shown in FIG. ₂ Mounting position P further downstream than ₃ At the (third position), an xy stage 65 driven by a pressing device 74 and a servomotor 66 are arranged. By performing the NC control of the servomotor 66, the position of the xy stage 65 with respect to the pressing device 74 can be accurately determined. The pressing device 74 is arranged above the carrier film 60, and the xy stage 65 is arranged below the carrier film 60. The pressing device 74 includes a pressing means 74a integrally provided with a positioning pin 74b inserted into a through hole 80 formed in the carrier film 60. The pressing means 74 a can be a pressing member whose contact surface with the carrier film 60 is adjusted to have substantially the same shape as the lithium flake 5. On the xy stage 65, a multiple case assembly 33 including a plurality of negative electrode cases 30 is arranged.
[0034]
As shown in FIG. 6, in the present embodiment, the strip 62 is pressed against the carrier film 60 so that the carrier film 60 is vertically upper and the strip 62 is lower, and cutting and transporting of the strip 62 are performed. At the same time, in the step of attaching the lithium flake 5 produced by the cutting to the negative electrode case 30, the negative electrode case 30 is made to wait further below the strip 62. Of course, it is also possible to press the band member 62 on the upper surface side of the carrier film 60 in the vertical direction, and it is also possible to adopt a form in which the line 200 itself in FIG. 6 is rotated by 90 °. However, considering the easiness of the process of accommodating the produced lithium flakes 5 in the negative electrode case 30, for example, the easiness of fixing the negative electrode case 30 (multiple case assembly 33) to the xy table 65, the present embodiment is considered. It is better to do so. Also, there is an advantage that even if a mounting error or the like occurs, it can be easily found. Furthermore, when the lithium flakes 5 are peeled off from the carrier film 60 and transferred to the negative electrode case 30, there is another reason that the lithium flakes 5 easily fall by their own weight.
[0035]
When the pressing means 74a shown in FIG. 6 contacts the carrier film 60 and presses the carrier film 60, the lithium flake 5 is pressed against the negative electrode case 30 (see FIG. 2). As a result, the lithium flakes 5 are peeled off from the carrier film 60 and are pressed against the main surface of the negative electrode current collector 7 forming the bottom of the negative electrode case 30, thereby being directly accommodated in the recess 2 of the negative electrode case 30. As described above, in the present embodiment, since the lithium flakes 5 are directly transferred from the carrier film 60 to the negative electrode case 30 without using a transporting means such as a suction pad or the like, there is no reduction in positioning accuracy due to the transport. Since the current collector plate 7 is a copper plate, the current collector plate 7 is more compatible with the lithium flake 5 than the carrier film 60, and there is almost no fear that a transfer error occurs. In order to make it more difficult for transfer errors to occur, it is conceivable that the main surface of the negative electrode current collector 7 serving as the bottom of the negative electrode case 30 is made rougher than the main surface of the carrier film 60 to which the lithium flakes 5 are pressed. obtain.
[0036]
Further, a specific method of transferring the lithium flake 5 to the negative electrode case 30 can be described as follows. That is, the pressing means 74 a is brought into contact with the lithium flake 5 via the carrier film 60, and the lithium flake 5 is pressed against the negative electrode case 30 while bending the carrier film 60 vertically downward, so that the lithium flake 5 is The film is transferred from the film 60 to the negative electrode case 30. The carrier film 60 is supported by the feed roller 75 and the like, but can be slightly bent downward. It is preferable to transfer the lithium flakes 5 by using the bending because it is not necessary to move the xy stage 65 in the z direction.
[0037]
Further, in the present embodiment, the negative electrode case 30 is configured as a multi-piece case assembly 33 in which a plurality of concave portions 2 are formed in the in-plane direction of the window frame 1 on the negative electrode side. To be transferred to the negative electrode case 30 (the mounting position P ₃ ), The plurality of case assemblies 33 are moved / stopped in synchronization with the movement / stop of the carrier film 60 and the band material 62 so that each of the recesses 2 moves sequentially. 5 is accommodated. According to such a method, the process of accommodating the lithium flakes 5 in the negative electrode case 30 can be performed continuously without interruption until the carrier film 60 or the band material 62 runs out, so that the productivity is extremely high.
[0038]
After the lithium flakes 5 as the negative electrode active material are accommodated in the negative electrode case 30 as described above, the separator 9 is attached to the window frame 1 as described with reference to FIG. Then, the positive electrode case 31 and the negative electrode case 30 each constituted as a multiple case assembly are adhered by an ultrasonic welding method or a heat welding method. After welding both, the plate-shaped battery 100 is obtained by cutting it into individual battery units.
[Brief description of the drawings]
FIG. 1 is a perspective view and a cross-sectional view of a plate-type battery.
FIG. 2 is a diagram simply illustrating a manufacturing process of a plate-type battery.
FIG. 3 is a diagram illustrating a manufacturing process of a multiple case assembly.
FIG. 4 is a diagram following FIG. 3;
FIG. 5 is a diagram following FIG. 4;
FIG. 6 is a schematic view showing a line for carrying out the method of the present invention in which a lithium flake is produced from a strip and accommodated in a negative electrode case.
FIG. 7 is a diagram illustrating a method for cutting a lithium strip according to the present invention.
FIG. 8 is a schematic side view of a cutting device showing a height relationship between a punch and a cutting blade according to the present invention.
FIG. 9 is a schematic diagram illustrating a positional relationship between a lithium flake and a positioning mark on the carrier film side.
FIG. 10 is a diagram illustrating a conventional method for obtaining a sheet piece by cutting a sheet-shaped strip into a predetermined shape.
[Explanation of symbols]
1,3 Window frame (framed exterior material)
2 recess
5 Lithium flakes (negative electrode active material)
6 Positive electrode active material
7,8 current collector
7c Main surface of negative electrode current collector
9 Separator
30 Negative electrode case (attached body)
31 Positive electrode case
33 Multi-piece case assembly
50 Remaining strip
60 Carrier film
60a Non-adhesion area
61 Supply reel for carrier film
62 Lithium strip
63 Supply reel for lithium strip
64 Collection reel
73a, 73b Cutting blade
73c punch
73d lifting base
80 Carrier film side alignment mark
100 plate type battery
WL width direction

Claims (14)

A method of producing a lithium flake from a lithium metal strip, and attaching the lithium flake to an attached body,
After the belt-shaped resin carrier film and the band material are relatively approached while being sent out such that the main surfaces thereof face each other, pressure is applied to both from above and below the facing surface, and the band material is pressed against the carrier film. The step of causing
A step of preparing a lithium flake by cutting the band material pressed onto the carrier film into a predetermined shape without dividing the carrier film;
Attaching the lithium flake to the attached body while peeling off the lithium flake from the carrier film,
A method for producing and attaching a lithium flake, comprising: 2. The method for producing and attaching a lithium flake according to claim 1, wherein the carrier film has at least one main surface subjected to a roughening treatment, and the band material is pressure-bonded to the roughened principal surface side. . The method for producing and attaching a lithium flake according to claim 1 or 2, wherein the carrier film and the band material are fed such that both of them repeatedly move and stop, and at the time of the stop, the above-described steps are performed. For the carrier film, a band wider than the band material is used, the band material does not protrude from the carrier film in the width direction, and the non-adhesion region is formed on at least one side in the width direction of the carrier film. The method for producing and attaching a lithium flake according to any one of claims 1 to 3, further comprising: arranging a non-adhesive region. 5. The lithium flake according to claim 4, wherein, when cutting the band material, a carrier film side alignment mark used when the lithium flake is attached to the attached body is formed in the non-adhesive region of the carrier film. How to make and attach. The method for producing and mounting a lithium flake according to claim 5, wherein the alignment mark on the carrier film side is a through hole penetrating the carrier film in a thickness direction. The cutting blade for producing the lithium flake and the punch for forming the through-hole are fixed to a lifting base, and even when the lifting base moves to a position where the punch penetrates the carrier film, the cutting blade is 7. The method for producing and mounting a lithium flake according to claim 6, wherein the relative height of the cutting blade and the punch is adjusted so as not to penetrate the carrier film. The carrier film, one end of which is fixed to a supply reel and the other end of which is previously fixed to a collection reel, is sent out from the supply reel by rotational driving of the supply reel and the collection reel,
In the step of producing the lithium flake, the strip is cut so as to be divided into the lithium flake and the remaining part of the band, and the remaining part of the band is wound and collected on the collection reel together with the carrier film. Item 8. The method for producing and attaching a lithium flake according to any one of Items 1 to 7. The carrier film is vertically pressed, the band material is pressed against the carrier film so that the band material is on the lower side, and the band material is cut and transported, and the lithium flake is attached to the attached body. The method for producing and attaching a lithium flake according to any one of claims 1 to 8, wherein in the attaching step, the attached body is made to stand by further below the band material. By pressing the pressing means against the lithium flake via the carrier film and pressing the lithium flake against the attached body while bending the carrier film vertically downward, the lithium flake is removed from the carrier film. 10. The method for producing and attaching a lithium flake according to claim 9, which is transferred to an object to be attached. 11. The method for manufacturing a battery, wherein the lithium flake according to any one of claims 1 to 10 is a negative electrode active material of a battery, and the attached body is at least a part of a battery. . A negative electrode case having a concave portion for accommodating a negative electrode active material is formed by bonding a negative electrode current collector plate to the negative electrode side frame-shaped exterior material so as to cover one opening of the negative electrode side frame-shaped exterior material made of a resin sheet. On the other hand, a belt-shaped resin carrier film and a lithium metal band material are brought closer to each other while being sent out such that their main surfaces are opposed to each other. The material is pressed against the carrier film, and the band material pressed onto the carrier film is cut into a predetermined shape without dividing the carrier film to prepare a lithium flake, and the lithium flake is removed from the carrier film. A step of forming a negative electrode to be housed in the negative electrode case while peeling off;
A separator forming step of attaching a separator to the negative electrode case so as to cover the lithium flakes,
On the separator, a positive electrode forming step of disposing a positive electrode active material and a positive electrode case formed of a positive electrode side frame-shaped exterior material and a positive electrode current collector plate that form a pair with the negative electrode case,
A method for producing a battery, comprising: The method for manufacturing a battery according to claim 12, wherein the lithium flake is directly housed in a concave portion of the negative electrode case by being pressed against a main surface of the negative electrode current collector plate forming a bottom of the negative electrode case. The negative electrode case is configured as a multiple-piece case assembly in which a plurality of the concave portions are formed in the in-plane direction of the negative electrode side frame-shaped exterior material,
The position where the lithium flakes are transferred from the carrier film to the negative electrode case is moved in synchronization with the movement / stop of the carrier film and the band material so that the recesses are sequentially moved. The method for manufacturing a battery according to claim 13, wherein the lithium flakes are individually accommodated in all the recesses.

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