JP7085976B2 - How to manufacture a secondary battery - Google Patents

Description

The present invention relates to a method for manufacturing a secondary battery.

A secondary battery such as a lithium ion secondary battery has a structure in which a positive electrode plate and a negative electrode plate are wound or laminated via a separator to form an electrode body, and the electrode body is housed in a battery case together with an electrolytic solution. is doing.

Each of the positive electrode plate and the negative electrode plate constituting the electrode body has an active material layer formed on the surface of the current collector. A plurality of current collectors provided at one ends of the positive electrode plate and the negative electrode plate are connected to external terminals provided on the sealing plate of the battery case via the current collector plates.

As a method of joining a plurality of stacked current collectors and a current collector plate, a method of joining by ultrasonic welding is known. Ultrasonic welding is performed by applying vibration energy by ultrasonic waves in parallel to a joint surface while sandwiching a laminated current collector and a current collector plate between a horn and an anvil under appropriate pressure. Further, in order to reliably sandwich the laminated current collector and the current collector plate, protrusions are provided on the surfaces of the horn and the anvil, respectively.

However, since the thickness of the current collector used for a lithium ion secondary battery or the like is very thin, a plate-shaped current collector plate and a stack of a plurality of such thin current collectors are ultrasonically welded. When joined, the current collector may come off. If the small pieces of the peeled current collector get into the battery during the assembly of the battery, the quality of the battery may be deteriorated.

In Patent Document 1, in order to solve such a problem, the shape of the protrusion provided on the surface of the horn is made arcuate, or a margin region in which the protrusion is not formed is provided around the horn. Is disclosed.

Japanese Unexamined Patent Publication No. 2012-125801

When the inventors of the present application investigated small pieces (dust generation) generated at the joint after joining a plurality of laminated current collectors and a current collector plate by ultrasonic welding, the film of the current collector was observed. I noticed that it contained larger pieces. Moreover, it was found that the size of this small piece was larger than the height of the protrusion provided on the anvil. Subsequent detailed analysis revealed that small pieces of this size were not formed by peeling from the current collector, but by scraping from the current collector plate.

Normally, the negative electrode current collector plate is made of copper, but small pieces (copper pieces) of this size scraped from the negative electrode current collector plate are placed on the positive electrode plate when the electrolytic solution is injected. When moved, small pieces (copper pieces) on the positive electrode plate may be melted by charging and discharging, and the melted copper may grow into dendrites on the negative electrode plate. As a result, the dendrite may break through the separator and cause an internal short circuit between the positive electrode plate and the negative electrode plate.

Conventionally, as small pieces generated when joining a plurality of laminated current collectors and current collector plates by ultrasonic welding, those peeled off from the current collectors have been recognized, but they have been scraped off from the current collector plates. What was supposed to be was not expected. Therefore, the problem of internal short circuits caused by small pieces scraped from the current collector plate was not considered at all.

The present invention has been made in view of this point, and the main object thereof is a small piece scraped from the current collector plate when the laminated current collector and the current collector plate are joined by ultrasonic welding. It is an object of the present invention to provide the manufacturing method of the secondary battery which can suppress the occurrence of.

The method for manufacturing a secondary battery according to one embodiment of the present invention is connected to a first electrode plate having a current collector, an electrode body including a second electrode plate having a polarity different from that of the first electrode plate, and a current collector. It is a method of manufacturing a secondary battery having a current collector plate and a laminated current collector connected to the current collector plate, and is a process of preparing an electrode body, a laminated current collector, and a current collector. The plate is joined by ultrasonic welding, and the step of joining by ultrasonic welding is a state in which the laminated current collector and the current collector plate are sandwiched between a horn and an anvil and pressed. In the process of joining by ultrasonic welding, the current collector plate is prevented from moving in the direction perpendicular to the pressing direction during ultrasonic welding. It is fixed by fixing means.

According to the present invention, there is a method for manufacturing a secondary battery capable of suppressing the generation of small pieces scraped from the current collector plate when the laminated current collector and the current collector plate are joined by ultrasonic welding. Can be provided.

The figure schematically shows the structure of the secondary battery in one Embodiment of this invention, FIG. 1 (a) is a sectional view, and FIG. 1 (b) is along the line Ib-Ib of FIG. 1 (a). It is a cross-sectional view. It is a figure which showed the process of joining the laminated negative electrode current collector and the negative electrode current collector plate by ultrasonic welding. 3A and 3B are views for explaining the fixing means, and in the cross-sectional view shown in FIG. 2, the anvil, the negative electrode current collector, and the horn are omitted, and only the negative electrode current collector plate is used as the horn. It is a plan view seen from the side. 4 (a) and 4 (b) are views for explaining the fixing means, and in the cross-sectional view shown in FIG. 2, the anvil, the negative electrode current collector, and the horn are omitted, and only the negative electrode current collector plate is used as the horn. It is a plan view seen from the side. 5 (a) and 5 (b) are views for explaining the fixing means, and FIG. 5 (a) is a cross-sectional view shown in FIG. 2, in which the negative electrode current collector and the horn are omitted, and the anvil and the negative electrode collection are omitted. The electric plate is a plan view seen from the horn side, and FIG. 5 (b) is a cross-sectional view taken along the line Vb-Vb of FIG. 5 (a). 6 (a) and 6 (b) are views for explaining the fixing means, and FIG. 6 (a) is a cross-sectional view shown in FIG. 2, in which the negative electrode current collector and the horn are omitted, and the anvil and the negative electrode collection are omitted. The electric plate is a plan view seen from the horn side, and FIG. 6B is a cross-sectional view taken along the line VIb-VIb of FIG. 6A. FIG. 7 is a view illustrating the fixing means, and is a plan view of the anvil and the negative electrode current collector plate viewed from the horn side in the cross-sectional view shown in FIG. 2, omitting the negative electrode current collector and the horn. FIG. 8 is a view illustrating the fixing means, and is a cross-sectional view of the anvil and the negative electrode current collector plate viewed from the side in the cross-sectional view shown in FIG. 2, omitting the negative electrode current collector and the horn.

As described above, when the plurality of laminated current collectors and the current collector plates are joined by ultrasonic welding, the present inventors seem to have scraped off the current collector plates, which was not previously expected. I got a new finding that small pieces are generated.

Specifically, in the joint portion between a plurality of negative electrode current collectors (copper foil: thickness 8 μm) and a negative electrode current collector plate (copper plate: thickness 1 mm) by ultrasonic welding, the negative electrode collection on the side in contact with the horn. Adhesive tape is attached to the surface of the electric body and the surface of the negative electrode current collector on the side in contact with the anvil, and the small pieces generated at the joint are transferred to the adhesive tape, and the size and number of generated small pieces are analyzed in detail. did. As a result, it was found that the number of small pieces generated on the surface of the negative electrode current collector plate on the anvil side was about 10 times larger than the number of small pieces generated on the surface of the negative electrode current collector on the horn side. As a feature of the small pieces, the size (about 10 to 100 μm) of the small pieces (copper pieces) generated on the surface of the negative electrode current collector plate on the anvil side is the small pieces (copper pieces) generated on the surface of the negative electrode current collector on the horn side. ) (About 5 to 20 μm) was also found to be larger.

In ultrasonic welding of a plurality of negative electrode current collectors and the negative electrode current collector plate, it is considered that the small pieces generated on the surface of the negative electrode current collector plate on the side in contact with the anvil are generated for the following reasons.

Conventionally, when the laminated current collector and the current collector plate are sandwiched between a horn and an anvil and pressed from both sides, a plurality of protrusions provided on the anvil are made to bite into the current collector plate to form a current collector plate. Ultrasonic welding was performed with the anvil fixed. That is, by pressing the current collector plate with the anvil, the current collector plate and the anvil are fixed so that a concave portion having a shape corresponding to the protrusion provided on the anvil is formed on the current collector plate. Therefore, conventionally, even if ultrasonic vibration is applied to the horn, the current collector plate does not move with respect to the anvil.

On the other hand, as the capacity and energy density of secondary batteries increase, the number of layers of the laminated current collectors is increasing. Accordingly, in ultrasonic welding of a plurality of current collectors and a current collector plate, the vibration energy (amplitude, frequency, application time) applied to the horn is also increasing.

Therefore, it is considered that the vibration applied to the horn is transmitted to the current collector plate via the current collector due to the increase in the vibration energy, and the current collector plate itself moves in conjunction with the vibration of the horn. In this case, since the anvil is fixed, friction occurs between the vibrating negative electrode current collector plate and the anvil, and as a result, the surface of the current collector plate on the side in contact with the anvil is caused by the protrusion provided on the anvil. It is considered to have been scraped.
In addition, the number of small pieces generated on the surface of the negative electrode current collector plate on the anvil side was larger than the number of small pieces generated on the surface of the negative electrode current collector on the horn side, and it occurred on the surface of the negative electrode current collector plate on the anvil side. It is also considered that the size of the small pieces was larger than the size of the small pieces generated on the surface of the negative electrode current collector on the horn side for the above reason.

Therefore, the present inventors can fix the anvil and the current collector plate only by biting the protrusion provided in the anvil into the current collector plate as in the conventional case when the vibration energy increases. It was difficult, and I thought that a separate means for restraining the current collector plate from moving was necessary, and came up with the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The present invention is not limited to the following embodiments. Further, it can be appropriately changed as long as it does not deviate from the range in which the effect of the present invention is exhibited.

1 (a) and 1 (b) are views schematically showing the configuration of a secondary battery according to an embodiment of the present invention, FIG. 1 (a) is a cross-sectional view, and FIG. 1 (b) is FIG. It is sectional drawing along the line Ib-Ib of (a).

As shown in FIGS. 1A and 1B, in the secondary battery 10 of the present embodiment, the electrode body 13 which is a power generation element is housed in the battery case 11 together with the electrolytic solution. Further, the opening of the battery case 11 is sealed with a sealing plate 12. Further, the negative electrode external terminal 15 and the positive electrode external terminal 17 each penetrate the through hole provided in the sealing plate 12 and are fixed to the sealing plate 12. Here, the electrode body 13 has a structure in which a positive electrode plate (second electrode plate) and a negative electrode plate (first electrode plate) are wound by a separator (both not shown). As the positive electrode plate, one in which a positive electrode active material layer containing a positive electrode active material is provided on the surface of a foil-shaped positive electrode current collector can be used. As the negative electrode plate, one in which a negative electrode active material layer containing a negative electrode active material is provided on the surface of a foil-shaped negative electrode current collector can be used. The positive electrode external terminal 17 and the negative electrode external terminal 15 are fixed to the sealing plate 12 via insulating members (not shown) provided on the upper surface and the lower surface of the sealing plate 12.

At one end of each of the positive electrode plate and the negative electrode plate, the positive electrode current collector 16 and the negative electrode current collector 14 on which the active material layer is not formed are exposed. At one end of the electrode body 13, the exposed portion of the positive electrode current collector 16 is wound around, so that the positive electrode current collector 16 is laminated. At the other end of the electrode body 13, the exposed portion of the negative electrode current collector 14 is wound around, so that the negative electrode current collector 14 is laminated. The positive electrode current collector 16 is connected to the positive electrode external terminal 17 via the positive electrode current collector plate 30. Further, the negative electrode current collector 14 is connected to the negative electrode external terminal 15 via the negative electrode current collector plate 20.

As shown in FIG. 1 (b), the laminated negative electrode current collectors 14 provided at one end of the negative electrode plate are bundled and bonded to the negative electrode current collector plate 20 by ultrasonic welding. Similarly, the laminated positive electrode current collectors 16 provided at one end of the positive electrode plate are bundled and joined to the positive electrode current collector plate 30 by ultrasonic welding.

When the secondary battery 10 is a non-aqueous electrolyte secondary battery, the positive electrode current collector 16, the positive electrode current collector plate 30, and the positive electrode external terminal 17 are preferably made of aluminum or an aluminum alloy. Further, the negative electrode current collector 14, the negative electrode current collector plate 20, and the negative electrode external terminal 15 are preferably copper or a copper alloy.

FIG. 2 is a diagram showing a process of joining the laminated negative electrode current collector 14 and the negative electrode current collector plate 20 by ultrasonic welding. Since the step of joining the laminated positive electrode current collector 16 and the positive electrode current collector plate 30 by ultrasonic welding can also be performed by the same method, the description thereof will be omitted.

As shown in FIG. 2, in ultrasonic welding, the laminated negative voltage collector 14 and the current collector plate 20 are sandwiched between the horn 40 and the anvil 50 and pressed in the direction of the arrow Y in the drawing. , Is performed by applying ultrasonic vibration to the horn 40 in the direction X perpendicular to the pressing direction Y.

Here, a plurality of protrusions (nar) 41 are provided on the surface of the horn 40. Then, by pressing the horn 40 from above the negative electrode current collector 14, the negative electrode current collector 14 is recessed by the protrusion 41, and the negative electrode current collector 14 and the negative electrode current collector plate 20 are rubbed by ultrasonic vibration. It is heated by heat and joined.

On the other hand, the surface of the anvil 50 on the side on which the negative electrode current collector plate 20 is placed is not provided with a plurality of protrusions for fixing the negative electrode current collector plate 20 as in the conventional case. Instead, as shown in FIG. 2, the negative electrode current collector plate 20 is in a direction perpendicular to the pressing direction Y from both sides with respect to the facing side surfaces 21a and 21b of the negative electrode current collector plate 20 during ultrasonic welding. By applying a predetermined force F to X, the negative electrode current collector plate 20 is fixed so as not to move in the direction X perpendicular to the pressing direction Y.

As a result, even if the ultrasonic vibration applied to the horn is transmitted to the negative electrode current collector plate 20 via the negative electrode current collector 14, the negative electrode current collector plate 20 itself moves in conjunction with the vibration of the horn 40. There is no. Therefore, since friction does not occur between the negative electrode current collector plate 20 and the anvil 50, the surface of the negative electrode current collector plate 20 on the side in contact with the anvil 50 is not scraped. As a result, even if the vibration energy (amplitude, frequency, application time) applied to the horn 40 increases with the increase in the number of layers of the negative electrode current collector 14, it is caused by the small pieces scraped from the negative electrode current collector plate 20. Therefore, it is possible to suppress the occurrence of an internal short circuit. Further, since the protrusion is not provided on the surface of the anvil 50, the surface of the negative electrode current collector plate 20 on the anvil 50 side is not dented by the protrusion. Therefore, deformation of the negative electrode current collector plate 20 due to the dent can be suppressed.

Note that FIG. 2 shows an example in which the force F applied to the negative electrode current collector plate 20 is applied in the direction perpendicular to the pressing direction Y and in the same direction as the vibration direction X of the horn 40, but the vibration of the horn 40 is shown. It may be added in the direction perpendicular to the direction X (the direction perpendicular to the paper surface). Even in this case, if the negative electrode current collector plate 20 itself is restrained so as not to move during ultrasonic welding, the surface of the negative electrode current collector plate 20 on the side in contact with the anvil 50 will not be scraped.

As described above, in the method of manufacturing the secondary battery in the present embodiment, the step of preparing the electrode body 13 and the laminated current collectors 14 and 16 and the current collector plates 20 and 30 are ultrasonically welded. In the step of joining by ultrasonic welding, the laminated current collectors 14 and 16 and the current collector plates 20 and 30 are sandwiched between the horn 40 and the anvil 50 and pressed. This is done by applying ultrasonic vibration to the horn 40 in the direction perpendicular to the pressing direction, and the current collector plates 20 and 30 are fixed by fixing means so as not to move in the direction perpendicular to the pressing direction during ultrasonic welding. Has been done.

By such a method, when a plurality of current collectors 14 and 16 and current collector plates 20 and 30 are joined by ultrasonic welding, the generation of small pieces scraped from the current collector plates 20 and 30 is suppressed. Can be done. As a result, even if the vibration energy (amplitude, frequency, application time) applied to the horn 40 increases as the number of layers of the current collectors 14 and 16 increases, small pieces scraped from the current collector plates 20 and 30 are scraped off. It is possible to suppress the occurrence of an internal short circuit due to the above.

In the present embodiment, the means (fixing means) for fixing the negative electrode current collector plate 20 so as not to move in the direction perpendicular to the pressing direction Y during ultrasonic welding is not particularly limited, but for example, FIGS. 3 to 8 Fixing means as shown in the above can be used.

3A and 3B are cross-sectional views shown in FIG. 2, in which the anvil 50, the negative electrode current collector 14, and the horn 40 are omitted, and only the negative electrode current collector plate 20 is viewed from the horn 40 side. It is a plan view.

As shown in FIG. 3A, a pair of blocks 60 and 61 are arranged on both sides of the negative electrode current collector plates 20 with respect to the facing side surfaces 21a and 21b. Here, the pair of blocks 60 and 61 correspond to the fixing means. Further, the pair of blocks 60 and 61 may be a part of the anvil 50.

The block 60 is a fixed block fixed at a predetermined position, and the side surface 21a of the negative electrode current collector plate 20 is brought into contact with the side surface of the fixed block 60 before ultrasonic welding is performed. On the other hand, the block 61 is a movable block that can move in a direction perpendicular to the pressing direction Y of the horn 40 (here, the same direction as the vibration direction X of the horn 40).

During ultrasonic welding, as shown in FIG. 3B, the negative electrode current collector plate 20 is perpendicular to the pressing direction Y by pressing the pair of blocks 60, 61 in the direction perpendicular to the pressing direction Y. It is fixed so that it does not move in the direction. The pressing force F may be appropriately determined so as to prevent the negative electrode current collector plate 20 from moving according to the vibration energy (amplitude, frequency, application time) applied to the horn 40. Further, the pair of blocks 60 and 61 may be arranged in a direction perpendicular to the pressing direction Y and perpendicular to the vibration direction X of the horn 40 (left-right direction on the paper surface).

The pair of blocks 60 and 61 are in contact with the pair of side surfaces existing in the negative electrode current collector plate 20 before they are in contact with the pair of blocks 60 and 61.

4A and 4B are cross-sectional views shown in FIG. 2, in which the anvil 50, the negative electrode current collector 14, and the horn 40 are omitted, and only the negative electrode current collector plate 20 is viewed from the horn 40 side. It is a plan view.

As shown in FIG. 4A, an L-shaped block 60 having a side surface that abuts on the orthogonal side surfaces 21a and 22a of the negative electrode current collector plate 20, and the orthogonal side surface 21b of the negative electrode current collector plate 20. Blocks 61 and 62 having side surfaces that come into contact with each other are arranged with respect to 22b. Here, the block 60 is a fixed block fixed at a predetermined position, and the side surfaces 21a and 22a of the negative electrode current collector plate 20 are hit against the side surfaces of the fixed block 60, respectively, before performing ultrasonic welding. Let me touch you. On the other hand, the blocks 61 and 62 are movable blocks that are perpendicular to the pressing direction Y of the horn 40 and can be moved in directions orthogonal to each other (the vibration direction X of the horn 40 and the direction perpendicular to the vibration direction X). be. Here, the fixed block 60 and the movable 61, 62 correspond to the fixing means. Further, the fixed block 60 and the movable 61, 62 may be a part of the anvil 50.

During ultrasonic welding, as shown in FIG. 4B, the movable blocks 61 and 62 are pressed against the side surfaces 21b and 22b of the negative electrode current collector plate 20 in the direction perpendicular to the pressing direction Y, respectively. The negative electrode current collector plate 20 is fixed so as not to move in the direction perpendicular to the pressing direction Y.

Such fixing means is provided with respect to the pair of side surfaces (21a, 21b) and (22a, 22b) of the negative electrode current collector plate 20 from the biaxial directions, respectively, with the pair of blocks (60, 61), (60, Since 62) can be pressed, the negative electrode current collector plate 20 can be more reliably fixed so as not to move in the direction perpendicular to the pressing direction Y.

5A is a plan view of the anvil 50 and the negative electrode current collector plate 20 viewed from the horn 40 side in the cross-sectional view shown in FIG. 2, omitting the negative electrode current collector 14 and the horn 40. 5 (b) is a cross-sectional view taken along the line Vb-Vb of FIG. 5 (a).

As shown in FIGS. 5A and 5B, a recess 51 is formed on the surface of the anvil 50, and the negative electrode current collector plate 20 is fitted in the recess 51. As a result, even if the ultrasonic vibration of the horn 40 is transmitted to the negative electrode current collector plate 20 via the negative electrode current collector 14, the negative electrode current collector plate 20 does not move in conjunction with the vibration of the horn 40. As a result, the negative electrode current collector plate 20 can be fixed so as not to move in the direction perpendicular to the pressing direction Y.

FIG. 6A is a plan view of the anvil 50 and the negative electrode current collector plate 20 as viewed from the horn 40 side, omitting the negative electrode current collector 14 and the horn 40 in the cross-sectional view shown in FIG. 6 (b) is a cross-sectional view taken along the line VIb-VIb of FIG. 5 (a).

As shown in FIGS. 6A and 6B, a protrusion 52 is formed on the surface of the anvil 50, and a through hole 23 formed in the negative electrode current collector plate 20 is fitted in the protrusion 52. As a result, even if the ultrasonic vibration of the horn 40 is transmitted to the negative electrode current collector plate 20 via the negative electrode current collector 14, the negative electrode current collector plate 20 is fixed so as not to move in the direction perpendicular to the pressing direction Y. Can be done. The negative electrode current collector plate 20 has a through hole 23 in a state before being brought into contact with the anvil 50.

FIG. 7 is a plan view of the anvil 50 and the negative electrode current collector plate 20 as viewed from the horn 40 side, omitting the negative electrode current collector 14 and the horn 40 in the cross-sectional view shown in FIG.

As shown in FIG. 7, a pair of protrusions 53 are formed on the surface of the anvil 50, and a pair of grooves 24 formed in the negative electrode current collector plate 20 are fitted in the pair of protrusions 53. As a result, even if the ultrasonic vibration of the horn 40 is transmitted to the negative electrode current collector plate 20 via the negative electrode current collector 14, the negative electrode current collector plate 20 is fixed so as not to move in the direction perpendicular to the pressing direction Y. be able to. The negative electrode current collector plate 20 has a pair of grooves 24 in a state before being brought into contact with the anvil 50.

FIG. 8 is a cross-sectional view of the anvil 50 and the negative electrode current collector plate 20 viewed from the side in the cross-sectional view shown in FIG. 2, omitting the negative electrode current collector 14 and the horn 40.

As shown in FIG. 8, the negative electrode current collector plate 20 is provided with a bent portion 25, and recesses 51 and 54 into which the negative electrode current collector plate 20 including the bent portion 25 is fitted are formed on the surface of the anvil 50. Has been done. By fitting the negative electrode current collector plate 20 including the bent portion 25 into the recesses 51 and 54, even if the ultrasonic vibration of the horn 40 is transmitted to the negative electrode current collector plate 20 via the negative electrode current collector 14. The negative electrode current collector plate 20 can be fixed so as not to move in the direction perpendicular to the pressing direction Y.
The negative electrode current collector plate 20 has a bent portion 25 in a state before being brought into contact with the anvil 50.
Although the present invention has been described above in terms of preferred embodiments, such a description is not a limitation, and of course, various modifications can be made. For example, in the above embodiment, the surface of the anvil 50 is processed flat, but in addition to the fixing means of the present invention, as in the conventional case, a protrusion is provided on the surface of the anvil 50 to provide a negative electrode current collector plate. Ultrasonic welding may be performed in a state where the protrusion provided on the anvil 50 is bitten into the 20. Even in this case, if the negative electrode current collector plate 20 itself is restrained so as not to move during ultrasonic welding, the surface of the negative electrode current collector plate 20 on the side in contact with the anvil 50 will not be scraped. Further, by utilizing the restraining force due to the protrusion provided on the anvil 50, it is possible to reduce the amount of F applied to the facing side surfaces 21a and 21b of the negative electrode current collector plate 20.

Further, in the above embodiment, the electrode body 13 having a structure in which the positive electrode plate and the negative electrode plate are wound via the separator has been described as an example, but the electrode body has a structure in which the positive electrode plate and the negative electrode plate are laminated via the separator. It may be 13. In this case, the plurality of current collectors 14 and 16 provided at one ends of the positive electrode plate and the negative electrode plate may be tab-shaped.

Further, in the above embodiment, the electrode body 13 is arranged so that its winding shaft is parallel to the bottom of the battery case 11, but the winding shaft is oriented to be perpendicular to the bottom of the battery case 11. The electrode body 13 may be arranged in the vehicle.

Further, known materials can be used for the positive electrode and negative electrode current collectors, current collector plates, active material layers, separators, non-aqueous electrolytic solutions and the like.

10 Rechargeable battery
11 Battery case
12 Seal plate
13 Electrode body
14 Negative electrode current collector
15 Negative electrode external terminal
16 Positive electrode current collector
17 Positive electrode external terminal
20 Current collector plate
20 Negative electrode current collector plate
21a, 21b A pair of side surfaces of the negative electrode current collector plate
22a, 22b A pair of side surfaces of the negative electrode current collector plate
23 Through hole
24 grooves
25 Bending part
30 Positive electrode current collector plate
40 horn
41 protrusion
50 anvil
51, 54 concave
52, 53 protrusions
60 fixed block
61, 62 Movable block

Claims (5)

The collector is provided with a first electrode plate having a current collector, an electrode body including a second electrode plate having a polarity different from that of the first electrode plate, and a current collector plate connected to the current collector. It is a method of manufacturing a secondary battery in which an electric body is connected to the current collector plate.
The process of preparing the electrode body and
A process of joining the laminated current collector and the current collector plate by ultrasonic welding.
Have,
In the step of joining by ultrasonic welding, the laminated current collector and the current collector plate are sandwiched between a horn and an anvil and pressed, and the horn is subjected to ultrasonic vibration in a direction perpendicular to the pressing direction. Is done by adding
A method for manufacturing a secondary battery, wherein in the step of joining by ultrasonic welding, the current collector plate is fixed by a fixing means so as not to move in a direction perpendicular to the pressing direction during ultrasonic welding. The current collector plate has a pair of opposing sides in a state before being abutted by the anvil.
In the step of joining by ultrasonic welding, the current collector plate is prevented from moving in the direction perpendicular to the pressing direction by abutting the fixing jigs on the pair of facing side surfaces of the current collector plate. The method for manufacturing a fixed secondary battery according to claim 1. The anvil has a recess on the surface and
In the step of joining by ultrasonic welding, the current collector plate is fitted into the recess of the anvil so that the current collector plate is fixed so as not to move in the direction perpendicular to the pressing direction. Item 1. The method for manufacturing a secondary battery according to Item 1. The current collector plate has a through hole in a state before being abutted by the anvil.
In the step of joining by ultrasonic welding, the through hole of the current collector plate is fitted into the protrusion formed on the surface of the anvil, so that the current collector plate is placed in a direction perpendicular to the pressing direction. The method for manufacturing a secondary battery according to claim 1, wherein the secondary battery is fixed so as not to move. The first electrode plate is a negative electrode plate and is a negative electrode plate.
The second electrode plate is a positive electrode plate and is a positive electrode plate.
The negative electrode plate has a foil-shaped negative electrode current collector and a negative electrode active material layer formed on the negative electrode current collector.
The negative electrode current collector is made of copper or a copper alloy.
The method for manufacturing a secondary battery according to any one of claims 1 to 4, wherein the current collector is the negative electrode current collector.

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