TWM630563U - Laser welding equipment of battery module - Google Patents

Abstract

The utility model provides a laser welding equipment for a battery module, which comprises a laser device, a pressing plate and a plurality of elastic units. The pressing plate includes a plurality of perforations, respectively facing the plurality of elastic units. When welding the battery module, a plurality of battery cells can be placed between each elastic unit and the pressing plate, and a conductive sheet is placed between the pressing plate and the battery core, and the laser beam generated by the laser device is Conductive sheet projected on top of battery cell via perforation. The pressing plate compresses the elastic unit through the conductive sheets and the battery cells, so that the conductive sheets actually contact each battery cell. Through the welding equipment of the present invention, the battery cell can be prevented from not actually contacting the conductive sheet, and the welding yield can be effectively improved.

Description

Laser welding equipment for battery modules

The utility model relates to a laser welding equipment for a battery module, which can prevent the battery core from not really contacting the conductive sheet during the laser welding process, and can effectively improve the welding yield.

Secondary batteries mainly include nickel-metal hydride batteries, nickel-cadmium batteries, lithium-ion batteries, and lithium polymer batteries. Discharge and other advantages, and are widely used in portable electronic products such as mobile phones, notebook computers, digital cameras, etc., in recent years, it has been extended to the automotive field.

The structure of the battery cell mainly includes the positive electrode material, the electrolyte, the negative electrode material, the separator and the shell, wherein the separator separates the positive electrode material and the negative electrode material to avoid short circuit, and the electrolyte is arranged on the porous separator. , and works as a conduction of ionic charges. The casing is used to cover the above-mentioned positive electrode material, separator, electrolyte and negative electrode material. Generally speaking, the casing is usually made of metal material.

When in use, a plurality of battery cells are connected in series and/or in parallel through the battery lead frame to form a battery pack, so that the battery pack can output the voltage required by the product. Generally speaking, the battery lead frame and the battery core are connected by welding, and the temperature of the battery lead frame and the battery core is increased during the welding process, so that the battery lead frame is connected to the battery core. However, in the welding process, taking laser welding as an example, if the battery lead frame does not contact the positive or negative electrode of the battery cell, it may cause the battery lead frame to fail to connect to the positive or negative electrode of the battery cell, resulting in welding failure. .

In order to overcome the problems of the prior art and improve the welding yield of battery modules, the present invention proposes a novel laser welding equipment for battery modules. During the welding process, the welding position of each battery cell can be kept on the same plane or the same height, so that the conductive sheet can be placed horizontally on the battery cell, and close to the welding position of the battery cell, so as to reduce the situation of welding failure.

An object of the present invention is to provide a laser welding equipment for a battery module, which mainly includes a pressing plate and a plurality of elastic units, wherein the battery core and the conductive sheet are placed between the pressing plate and the elastic units. During the welding process, the pressing plate will compress the elastic unit through the conductive sheet and the battery cell, wherein the compressed length of each elastic unit is related to the height of the battery cell, so that the welding position of the battery cell connecting the conductive sheet is at the same or similar position. On the plane, and prevent the formation of an excessive gap between the conductive sheet and the welding position of the battery core.

A plurality of perforations are arranged on the pressing plate, respectively facing the elastic units, and there are battery cells and conductive sheets between the perforations and the elastic units. The laser beam generated by the laser device will be projected on the conductive sheet through the perforation. Because during the welding process, the conductive sheet will be close to the welding position of the battery cell. The conductive sheet heated by the laser beam will transfer heat to the welding position of the contacting battery core, so that the welding position of the conductive sheet and the battery core will melt and form a molten pool, and the welding of the conductive sheet and the battery core will be completed after cooling.

Ideally, each cell would have the same height, and the conductive sheet would have the same thickness. After each battery cell is placed on a flat stage and a conductive sheet is placed on the battery cell, the combined height of each battery cell and each conductive sheet will be the same. Since each conductive sheet is located at the same height and has the same distance from the laser device, the laser beam generated by the laser device can be focused on each conductive sheet to heat the conductive sheet and the battery cells adjacent to the conductive sheet. Position of welding.

However, in practical applications, each battery cell and each conductive sheet will have different heights and thicknesses due to manufacturing tolerances. Although the height difference of each battery cell and each conductive sheet is within the allowable range, it will not affect the battery cell. use. However, in the process of welding the conductive sheets and the battery cores, the height difference of each battery cell may cause the conductive sheets to be inclined, resulting in different distances between the conductive sheets and the laser device. As a result, the laser beam generated by the laser device may not be able to focus on each conductive sheet, so that the conductive sheet and the welding position of the battery cell cannot be heated smoothly.

The new type of laser welding equipment for battery modules can eliminate the height difference of each battery cell and/or conductive sheet through the elastic unit, so that the laser beam generated by the laser device can be focused on each conductive sheet, and the conductive sheet can be avoided. The problem of not being able to stick to the welding position of the battery cell can effectively improve the yield of welding the conductive sheet and the battery cell.

In order to achieve the above purpose, the present invention proposes a laser welding equipment for a battery module, which is used for welding a plurality of battery cells and a plurality of conductive sheets, including: a laser device for generating a laser beam; a pressing plate , including a plurality of perforations, and connected to the battery cells through a conductive sheet, wherein the plurality of perforations correspond to a plurality of battery cells respectively, and the laser beam generated by the laser device is projected on the conductive sheet through the perforations of the pressing plate; and a plurality of elastic units, Facing the plurality of perforations of the pressing plate, the battery cells are located between the perforations of the pressing plate and the elastic unit.

In another embodiment of the present invention, the battery cell includes a first bottom surface, a second bottom surface and a side surface, the side surface is located between the first bottom surface and the second bottom surface, and is used to connect the first bottom surface and the second bottom surface, and the pressure The plywood is connected to the first bottom surface of the battery cell through the conductive sheet, and the elastic unit is connected to the second bottom surface of the battery cell.

In another embodiment of the present invention, a base is included, and one end of the plurality of elastic units is connected to the base.

In another embodiment of the present invention, a plurality of carrier plates are respectively connected to the other ends of the plurality of elastic units, and the elastic units are connected to the second bottom surfaces of the battery cells via the carrier plates.

In another embodiment of the present invention, the carrier plate includes a groove for accommodating battery cells.

In another embodiment of the present invention, a fixing frame is included between the base and the pressing plate, and is used for fixing the position of the battery cell.

In another embodiment of the present invention, the carrier plate is insulating.

Please refer to FIG. 1 and FIG. 2 , which are a schematic cross-sectional view and a top perspective view of an embodiment of a laser welding apparatus for a novel battery module, respectively. As shown in the figure, the laser welding equipment 10 of the battery module is used for welding a plurality of battery cells 12 and a plurality of conductive sheets 14 , and includes a laser device 11 , a pressing plate 13 and a plurality of elastic units 15 . At this time, a plurality of battery cells 12 and at least one conductive sheet 14 can be placed between the pressing plate 13 and the elastic unit 15 .

The pressing plate 13 can be plate-shaped and includes a plurality of through holes 131 . In an embodiment of the present invention, the number of elastic units 15 is the same as the number of through holes 131 , and each elastic unit 15 faces each through hole 131 on the pressing plate 13 , for example, the elastic unit 15 may be a spring.

During the laser welding process, each battery cell 12 is placed on each elastic unit 15 respectively, and the conductive sheet 14 is placed above the battery cell 12 , so that the conductive sheet 14 and the battery cell 12 are located on the pressing plate 13 and the elastic unit 15 between. In addition, the conductive sheet 14 is located between the battery cells 12 and the pressing plate 13 , and each through hole 131 of the pressing plate 13 corresponds to each battery cell 12 respectively. The laser beam L generated by the laser device 11 is projected onto the conductive sheet 14 through the through holes 131 of the pressing plate 13 to weld the battery core 12 and the conductive sheet 14 .

In an embodiment of the present invention, the battery cell 12 is a columnar body, and includes a first bottom surface 121 , a second bottom surface 123 and a side surface 125 , wherein the side surface 125 is located between the first bottom surface 121 and the second bottom surface 123 , The first bottom surface 121 and the second bottom surface 123 are connected. For example, the battery cell 12 can be a cylinder, and the first bottom surface 121 and the second bottom surface 123 are the positive electrode and the negative electrode, respectively.

The second bottom surface 123 of the battery cell 12 can be placed on the elastic unit 15 , and the conductive sheet 14 can be placed on the first bottom surface 121 of the battery cell 12 , so that the pressing plate 13 is connected to the first bottom surface 121 of the battery cell 12 via the conductive sheet 14 , the position where the first bottom surface 121 of the battery cell 12 contacts the conductive sheet 14 can be defined as a welding position. The pressing plate 13 is positioned on the conductive sheet 14 , and the through holes 131 of the pressing plate 13 are aligned with the first bottom surface 121 of the battery cell 12 through the conductive sheet 14 , for example, aligned with the welding position of the conductive sheet 14 and the battery cell 12 .

The pressing plate 13 can pressurize the elastic unit 15 through the conductive sheet 14 and the battery cell 12 , so that the conductive sheet 14 is indeed in contact with the first bottom surface 121 of the battery cell 12 . Then, when the laser device 11 projects the laser beam L on the conductive sheet 14 through the through hole 131 , the first bottom surface 121 of the battery cell 12 and the connected conductive sheet 14 can be welded.

In an ideal state, each battery cell 12 will have the same height, and the conductive sheet 14 will also have the same thickness, so that each conductive sheet 14 will have the same total height after being placed on each battery cell 12 . Since each conductive sheet 14 is located at the same height and maintains the same distance from the laser device 11 , the laser beam L generated by the laser device 11 can be smoothly focused on each conductive sheet 14 and heat the conductive sheet 14 and the battery The first bottom surface 121 of the core 12 .

However, in practical application, each battery cell 12 and each conductive sheet 14 have different heights due to manufacturing tolerances, and each conductive sheet 14 also has different thicknesses. After placing the second bottom surface 123 of each battery cell 12 on a flat surface, and placing the conductive sheet 14 on the first bottom surface 121 of the battery cell 12 . The conductive sheet 14 placed on the first bottom surface 121 of the battery cell 12 may be inclined. For example, the conductive sheet 14 may be inclined from the battery cell 12 with a higher height to the battery cell 12 with a lower height, so that the conductive sheet 14 cannot be tightly connected. It is attached to the first bottom surface 121 of the battery core 12 , and there is a gap therebetween, which is not conducive to subsequent welding of the conductive sheet 14 and the first bottom surface 121 of the battery core 12 through the laser device 11 .

Specifically, when there is a gap between the conductive sheet 14 and the first bottom surface 121 of the battery cell 12 , the heat on the conductive sheet 14 may not be effectively transferred to the first bottom surface of the battery cell 12 under the conductive sheet 14 through the gap. 121 , so that the first bottom surface 121 of the battery cell 12 cannot be heated to a predetermined temperature, such as the melting point of the first bottom surface 121 of the battery cell 12 .

In addition, the conductive sheet 14 and/or the first bottom surface 121 of the battery cell heated and melted by the laser beam L may not be able to cross the gap and contact each other, thereby causing the welding failure between the conductive sheet 14 and the battery cell 12 .

In addition, when each conductive sheet 14 is placed obliquely, the distance between each conductive sheet 14 and the laser device 11 will also be different. As a result, the laser beam L generated by the laser device 11 may not be able to focus on all the conductive sheets 14 , so that the laser beam L cannot effectively heat all the conductive sheets 14 and the battery cells 12 .

In order to avoid the above situation, the laser welding equipment 10 for the battery module proposed by the present invention is provided with a plurality of elastic units 15 on the opposite side of the pressing plate 13. During the laser welding process, the pressing plate 13 will pass through the conductive sheet 14 and The battery cell 12 presses the elastic unit 15 and compresses the elastic unit 15 . In practical application, each battery cell 12 corresponds to an elastic unit 15 , and the height of each battery cell 12 is adjusted through each elastic unit 15 respectively.

When the heights of the battery cells 12 are different, the compressed lengths of the elastic units 15 will also be different. For example, if the height of one battery cell 12 of the plurality of battery cells 12 is greater than that of the other battery cells 12 , the compressed length of the elastic unit 15 connected to the battery cell 12 with the larger height will be smaller than that of the other elastic units. 15. Conversely, if the height of one of the battery cells 12 is smaller than that of the other battery cells 12 , the compressed length of the elastic unit 15 connected to the battery cell 12 with the smaller height will be larger than that of the other elastic units 15 . In practical applications, the heights of the battery cells 12 for laser welding may be different, and the lengths of the elastic units 15 compressed by the battery cells 12 may also be different.

Specifically, the present invention can eliminate the height difference between the battery cells 12 through the compressed length of the plurality of elastic units 15 , so that the first bottom surfaces 121 of the battery cells 12 contacting the conductive sheet 14 are all maintained at the same height , and/or all the conductive sheets 14 are located at the same height, for example, at the same level. In other words, after each battery cell 12 and each conductive sheet 14 are placed on the elastic unit 15 and pressed by the pressing plate 13, the distance between each conductive sheet 14 and the laser device 11 will be the same, so that the laser device The laser beam L generated by 11 can be projected and focused on the conductive sheet 14 .

In addition, each conductive sheet 14 is in close contact with the first bottom surface 121 of each battery cell 12 to prevent an excessively large gap from being formed between the conductive sheet 14 and the first bottom surface 121 of the battery cell 12 . The laser device 11 can effectively heat the conductive sheet 14 and the first bottom surface 121 of the battery core 12 to melt part of the conductive sheet 14 and the first bottom surface 121 and form a molten pool between them, which can greatly reduce the risk of welding failure. situation occurs.

In an embodiment of the present invention, one end of the plurality of elastic units 15 may be disposed on a base 17, and the other end of the elastic units 15 is used to connect the battery cells 12. For example, the base 17 may be a carrier or a plate-shaped body .

In another embodiment of the present invention, as shown in FIG. 3 and FIG. 4 , one end of the elastic unit 15 can be connected to the base 17 , and the other end of the elastic unit 15 is provided with a support plate 151 . In practical application, the second bottom surface 123 of the battery cell 12 can be placed on the carrier board 151 , so that the elastic unit 15 is connected to the second bottom surface 123 of the battery cell 12 via the carrier board 151 , and the pressing board 13 is connected via the conductive sheet 14 . , the battery cell 12 and the carrier plate 151 compress the elastic unit 15 . In an embodiment of the present invention, a groove may be provided on the surface of the carrier plate 151 facing the pressing plate 13 for accommodating, positioning or temporarily fixing the battery cells 12 .

In practical application, the carrier plate 151 can be insulated and used to isolate the elastic unit 15 and the battery cells 12 . For example, the elastic unit 15 can be a metal spring, and the carrier plate 151 is made of insulating material, and is used to isolate the battery cell 12 and the elastic unit 15 to avoid short circuit of the battery cell 12 .

As shown in FIG. 5 and FIG. 6 , after the welding of the first bottom surface 121 of the battery cell 12 and the conductive sheet 14 is completed, the battery cell 12 and the conductive sheet 14 can be reversed and placed on the plurality of elastic units 15 , wherein The first bottom surface 121 of the battery cell 12 is connected to the elastic unit 15 via the conductive sheet 14 .

Then another conductive sheet 14 can be placed on the second bottom surface 123 of the battery cell 12 , and the pressing plate 13 can be placed on the conductive sheet 14 connected to the second bottom surface 123 of the battery cell 12 . The pressing plate 13 can compress the elastic unit 15 through the conductive sheets 14 and the battery cells 12 , so that the second bottom surfaces 123 of the battery cells 12 and/or the conductive sheets 14 connected to the second bottom surfaces 123 are maintained on the same plane.

The conductive sheets 14 will be close to the second bottom surface 123 of the battery core 12 , and the distances between the conductive sheets 14 and the laser device 11 will be similar, so that the laser beam L generated by the laser device 11 can pass through the pressing plate 13 . The through holes 131 focus on each conductive sheet 14 and heat the conductive sheet 14 and the second bottom surface 123 of the battery cell 12 to complete the welding of the second bottom surface 123 of the battery cell 12 and the conductive sheet 14 .

As shown in FIG. 3 and FIG. 6 , the laser welding equipment 10 for the battery module may include a fixing frame 19 . The fixing frame 19 is located between the base 17 and the pressing plate 13 and is used to fix the position of the battery cell 12 to prevent the battery The core 12 is dumped during welding. For example, the battery cell 12 is a cylinder, and the fixing frame 19 has a cylindrical perforation, wherein the area of the perforation is slightly larger than the cross-sectional area of the battery cell 12, so that the battery cell 12 can be placed in the through hole of the fixing frame 19 to fix the battery cell 12. position of each battery cell 12 .

The above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Modifications should be included in the scope of the patent application of the present invention.

10: Laser welding equipment for battery modules 11: Laser device 12: battery cell 121: The first bottom surface 123: Second bottom surface 125: side 13: plywood 131: Perforation 14: Conductive sheet 15: Elastic unit 151: Carrier plate 17: Base 19: Fixing frame L: laser beam

1 is a schematic cross-sectional view of an embodiment of a laser welding equipment for a new battery module.

FIG. 2 is a top perspective view of an embodiment of a laser welding equipment for a new battery module.

FIG. 3 is a schematic cross-sectional view of another embodiment of the laser welding equipment for the novel battery module.

FIG. 4 is a top perspective view of another embodiment of the laser welding equipment of the novel battery module.

FIG. 5 is a schematic cross-sectional view of another embodiment of the laser welding equipment for the novel battery module.

FIG. 6 is a schematic cross-sectional view of another embodiment of the laser welding equipment for the novel battery module.

10: Laser welding equipment for battery modules

11: Laser device

12: battery cell

121: The first bottom surface

123: Second bottom surface

125: side

13: plywood

131: Perforation

14: Conductive sheet

15: Elastic unit

17: Base

L: laser beam

Claims (7)

A laser welding equipment for a battery module is used for welding a plurality of battery cells and a plurality of conductive sheets, including: a laser device for generating a laser beam; a lamination plate including a plurality of through holes and connected to the battery cells through the conductive sheet, wherein the plurality of through holes correspond to the plurality of battery cells respectively, and the laser beam generated by the laser device passes through the through holes of the lamination plate projected onto the conductive sheet; and A plurality of elastic units face the plurality of through holes of the pressing plate, wherein the battery cell is located between the through holes of the pressing plate and the elastic unit. The laser welding equipment for a battery module as claimed in claim 1, wherein the battery core comprises a first bottom surface, a second bottom surface and a side surface, the side surface is located between the first bottom surface and the second bottom surface, and is used for The first bottom surface and the second bottom surface are connected, the pressing plate is connected to the first bottom surface of the battery cell through the conductive sheet, and the elastic unit is connected to the second bottom surface of the battery core. The laser welding equipment for a battery module according to claim 2 includes a base, and one end of the plurality of elastic units is connected to the base. The laser welding equipment for a battery module according to claim 3, comprising a plurality of carrier plates respectively connected to the other ends of the plurality of elastic units, and the elastic units are connected to the second bottom surface of the battery cell via the carrier plate. The laser welding equipment for a battery module according to claim 4, wherein the carrier plate includes a groove for accommodating the battery cell. The laser welding equipment for a battery module according to claim 3, comprising a fixing frame located between the base and the pressing plate, and used for fixing the position of the battery core. The laser welding equipment for a battery module according to claim 4, wherein the carrier board is insulated.

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