JP3241877U - battery module laser welding machine - Google Patents

Abstract

A laser welding machine for battery modules is provided in which a cell is reliably brought into contact with a conductive sheet and the welding yield is effectively improved. The present invention is a laser welding machine for battery modules including a laser device, a crimping plate and a plurality of elastic units, wherein the crimping plate includes a plurality of through-holes respectively facing the plurality of elastic units. When welding the battery module, a plurality of cells can be placed between each elastic unit and the crimping plate, and a conductive sheet can be placed between the crimping plate and the cells. A laser beam generated by a laser device is applied to the conductive sheet above the cells through the through holes. The crimping plate compresses the elastic unit through the conductive sheet and the cell to ensure contact of the conductive sheet with each cell. [Selection drawing] Fig. 1

Description

TECHNICAL FIELD The present invention relates to a battery module laser welder that can prevent a situation in which a cell does not come into contact with a conductive sheet during laser welding, thereby effectively improving the welding yield.

Secondary batteries mainly include nickel-metal hydride batteries, nickel-cadmium batteries, lithium-ion batteries, and lithium-polymer batteries. Lithium batteries have advantages such as high energy density, high operating voltage, wide operating temperature range, no memory effect, long life, and ability to withstand multiple charge/discharge cycles. In addition, they are widely used in portable electronic products such as mobile phones, laptop computers, digital cameras, etc., and in recent years, they are also used in the field of automobiles.

A cell structure mainly includes a positive electrode material, an electrolyte, a negative electrode material, a separator and a housing. The separator is for separating the positive electrode material and the negative electrode material to avoid a short circuit. Also, the electrolytic solution is placed in the porous separator and plays a role of conducting ionic charges. The housing is used to cover the cathode material, separator, electrolyte and anode material. In general, the housing is usually made of metal material.

In use, the conductive frame of the battery connects a plurality of cells in series and/or in parallel to form a group of cells, which group can output the voltage required for the product. Welding typically connects the cells to the conductive frame of the battery. The welding process raises the temperature of the battery's conductive frame and cell to connect the battery's conductive frame to the cell. However, in the welding process, the battery's conductive frame cannot be connected to the cell's positive or negative pole unless the battery's conductive frame is in firm contact with the cell's positive or negative pole, for example in the case of laser welding. , there is a risk of welding failure.

In order to overcome the problems of the prior art and improve the welding yield of battery modules, the present invention provides a novel battery module laser welding machine. In the welding process, the welding position of each cell can be held on the same plane or at the same height, so that the conductive sheet can be placed horizontally on the cell and adhered to the welding position of the cell, resulting in failure in welding. reduce the number of incidents.

One objective of the present invention is mainly to provide a laser welding machine for battery modules which includes a crimping plate and a plurality of elastic units, wherein cells and conductive sheets are arranged between the crimping plates and the elastic units. During the welding process, the crimping plate compresses the elastic unit through the conductive sheet and cells. The length after compression of each elastic unit is related to the height of the cell. As a result, the welding positions of the cells connected to the conductive sheet are positioned on the same or similar planes to prevent formation of too large a gap between the conductive sheet and the welding positions of the cells.

The crimping plate is provided with a plurality of through-holes respectively facing each elastic unit. There are cells and conductive sheets between the through-holes and the elastic unit. A laser beam generated by a laser device is irradiated onto the conductive sheet through the through hole. During the welding process, the conductive sheet is in intimate contact with the welding position of the cell. Thus, the conductive sheet heated by the laser beam transfers heat to the welding locations of the cells in contact. As a result, the welding position between the conductive sheet and the cell melts to form a molten pool, and the welding between the conductive sheet and the cell is completed after cooling.

In an ideal situation, each cell has the same height and the conductive sheets have the same thickness. In this case, after each cell is placed on a flat mounting table and the conductive sheet is placed on the cell, the total height of each cell and each conductive sheet is the same. As a result, all of the conductive sheets are positioned at the same height and the same distance from the laser device is maintained. , and the welding locations of the cells adjacent to the conductive sheet.

However, in practical applications, each cell and each conductive sheet has a different height and thickness due to manufacturing tolerances. The difference in height between each cell and the conductive sheet is within the allowable range and does not affect the use of the cells. However, in the process of welding the conductive sheet and the cells, the conductive sheet may be inclined due to the difference in the height of each cell, and the distance between each conductive sheet and the laser device may vary. In this case, the laser beam generated by the laser device cannot be focused on each conductive sheet, and there is a possibility that the welding position between the conductive sheet and the cell cannot be heated smoothly.

In the battery module laser welding machine of the present invention, the elastic unit can eliminate the height difference of each cell and/or the conductive sheet, so that the laser beam generated by the laser device can be focused on each conductive sheet. In addition, it is possible to avoid the problem that the conductive sheet cannot be brought into close contact with the welding position of the cell, and it is possible to effectively improve the yield of welding between the conductive sheet and the cell.

To achieve the above objectives, the present invention provides a battery module laser welding machine for welding multiple cells and multiple conductive sheets. The welding machine is a pressure plate including a laser device for generating a laser beam and a plurality of through-holes connected to the cells via a conductive sheet, the plurality of through-holes corresponding to the plurality of cells, respectively. a crimping plate in which a laser beam generated by a laser device is irradiated onto the conductive sheet through a through-hole of the crimping plate; and a plurality of elastic units facing the plurality of through-holes of the crimping plate. an elastic unit located between the through-hole of the crimping plate and the elastic unit.

In another embodiment of the invention, the cell includes a first bottom surface, a second bottom surface and side surfaces. A 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. The crimping plate is connected to the first bottom surface of the cell via the conductive sheet, and the elastic unit is connected to the second bottom surface of the cell.

Another embodiment of the invention includes a bottom base. One ends of the plurality of elastic units are connected to the bottom base.

Another embodiment of the present invention includes a plurality of loading plates respectively connected to the other ends of the plurality of elastic units. The elastic unit is connected to the second bottom surface of the cell via the loading plate.

In another embodiment of the invention, the loading plate includes recesses for receiving the cells.

Another embodiment of the invention includes a fixing frame located between the bottom base and the crimping plate and used to fix the position of the cells.

In another embodiment of the invention, the loading plate is insulating.

FIG. 1 is a schematic cross-sectional view of an embodiment of a laser welding machine for battery modules according to the present invention. FIG. 2 is a perspective plan view of an embodiment of the laser welding machine for battery modules according to the present invention. FIG. 3 is a schematic cross-sectional view of a further embodiment of a laser welding machine for battery modules according to the present invention. FIG. 4 is a plan perspective view of a further embodiment of the laser welding machine for battery modules according to the present invention. FIG. 5 is a schematic cross-sectional view of a further embodiment of a laser welding machine for battery modules according to the present invention. FIG. 6 is a schematic cross-sectional view of a further embodiment of a laser welding machine for battery modules according to the present invention.

Please refer to FIGS. These are a schematic sectional view and a plan perspective view, respectively, of an embodiment of a laser welding machine for battery modules according to the present invention. As shown, a battery module laser welder 10 is used to weld a plurality of cells 12 and a plurality of conductive sheets 14 , and includes a laser device 11 , a crimping plate 13 and a plurality of elastic units 15 . A plurality of cells 12 and at least one conductive sheet 14 may be placed between the crimping plate 13 and the elastic unit 15 during welding.

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

Each cell 12 is placed on each elastic unit 15 , and the conductive sheet 14 is placed above the cells 12 in the course of laser welding. This positions the conductive sheet 14 and the cells 12 between the crimping plate 13 and the elastic unit 15 . Also, the conductive sheet 14 is positioned between the cells 12 and the compression plate 13 , and each through-hole 131 of the compression plate 13 corresponds to each cell 12 . A laser beam L generated by the laser device 11 is irradiated onto the conductive sheet 14 via the through holes 131 of the compression plate 13 to weld the cells 12 and the conductive sheet 14 together.

In one embodiment of the present invention, the cell 12 is columnar and includes a first bottom surface 121 , a second bottom surface 123 and side surfaces 125 . The side surface 125 is located between the first bottom surface 121 and the second bottom surface 123 and connects the first bottom surface 121 and the second bottom surface 123 . For example, the cell 12 may be a cylindrical body, and the first bottom surface 121 and the second bottom surface 123 may be the positive electrode and the negative electrode, respectively.

A second bottom surface 123 of the cell 12 can be placed on the elastic unit 15 . Also, since the conductive sheet 14 is placed on the first bottom surface 121 of the cell 12 , the crimping plate 13 is connected to the first bottom surface 121 of the cell 12 via the conductive sheet 14 . A position of the first bottom surface 121 of the cell 12 that contacts the conductive sheet 14 can be defined as a welding position. A crimping plate 13 is positioned on the conductive sheet 14 . The through-holes 131 of the crimping plate 13 are butted against the first bottom surfaces 121 of the cells 12 via the conductive sheets 14 , for example, the welding positions of the conductive sheets 14 and the cells 12 .

The compression plate 13 can press the elastic unit 15 through the conductive sheet 14 and the cells 12 . This ensures that the conductive sheet 14 contacts the first bottom surface 121 of the cell 12 . After that, the laser device 11 irradiates the conductive sheet 14 with the laser beam L through the through-hole 131, so that the first bottom surface 121 of the cell 12 and the conductive sheet 14 to be connected can be welded.

In an ideal situation, each cell 12 has the same height and the conductive sheets 14 also have the same thickness so that each conductive sheet 14 has the same total height after being placed in each cell 12 . In this case, since the conductive sheets 14 are all positioned at the same height and kept at the same distance from the laser device 11, the laser beam L generated by the laser device 11 is smoothly converged on each conductive sheet 14. This allows the conductive sheet 14 and the first bottom surface 121 of the cell 12 to be heated.

However, in actual application, due to manufacturing tolerances of each cell 12 and each conductive sheet 14, each cell 12 has a different height and each conductive sheet 14 also has a different thickness. In this case, after placing the second bottom surface 123 of each cell 12 on a flat surface and placing the conductive sheet 14 on the first bottom surface 121 of the cell 12 , the conductive sheet 14 placed on the first bottom surface 121 of the cell 12 can have a slope. For example, the conductive sheet 14 slopes from tall cells 12 to short tall cells 12 . As a result, the conductive sheet 14 cannot be firmly adhered to the first bottom surface 121 of the cell 12, resulting in a gap between them. This is disadvantageous for subsequently welding the conductive sheet 14 and the first bottom surface 121 of the cell 12 with the laser device 11 .

Specifically, when there is a gap between the conductive sheet 14 and the first bottom surfaces 121 of the cells 12 , the heat on the conductive sheet 14 is effectively transferred to the first bottom surfaces 121 of the cells 12 below the conductive sheet 14 via the gaps. , and the first bottom surface 121 of the cell 12 may not be heated to a predetermined temperature (eg, the melting point of the first bottom surface 121 of the cell 12).

In addition, the conductive sheet 14 and/or the first bottom surface 121 of the cell, which is heated and melted by the laser beam L, cannot cross the gap and come into contact with each other, and as a result, the welding between the conductive sheet 14 and the cell 12 may fail. There is also

Moreover, when each conductive sheet 14 is arranged at an angle, each conductive sheet 14 has a different distance from the laser device 11 . In this case, the laser beam L generated by the laser device 11 cannot be converged on all the conductive sheets 14, and as a result, the laser beam L may not be able to effectively heat all of the conductive sheets 14 and cells 12. be.

In order to avoid the occurrence of the above situation, the battery module laser welding machine 10 provided by the present invention is provided with a plurality of elastic units 15 opposite the crimping plate 13 . During laser welding, the pressure plate 13 presses the elastic unit 15 through the conductive sheet 14 and the cell 12 to compress the elastic unit 15 . In actual application, each cell 12 must correspond to an elastic unit 15 and the height of each cell 12 must be adjusted by each elastic unit 15 .

If the heights of the cells 12 are different, the lengths of the elastic units 15 after compression are also different. For example, if one cell 12 among the plurality of cells 12 has a greater height than the other cells 12, the length of the elastic unit 15 connected to the cell 12 having the greater height after compression is equal to that of the other elastic units 15 be smaller than Conversely, if the height of one of the cells 12 is smaller than that of the other cells 12, the length of the elastic unit 15 connected to the cell 12 having the smaller height after compression is greater than that of the other elastic units 15. will also grow. In practical applications, the heights of the laser welded cells 12 may all be different. In this case, the length of the elastic unit 15 after being compressed by each cell 12 is also different.

Specifically, in the present invention, the height difference between the cells 12 can be eliminated by adjusting the compressed lengths of the plurality of elastic units 15 . This keeps the first bottom surfaces 121 of the cells 12 in contact with the conductive sheet 14 at the same height. and/or the conductive sheets 14 are positioned at the same height, eg, at the same horizontal height. In other words, after each cell 12 and each conductive sheet 14 is placed on the elastic unit 15 and pressed by the compression plate 13, the distance between each conductive sheet 14 and the laser device 11 becomes the same. A laser beam L generated by the device 11 is irradiated onto the conductive sheet 14 and converged.

In addition, each conductive sheet 14 is in close contact with the first bottom surface 121 of each cell 12 to prevent formation of too large a gap between the conductive sheet 14 and the first bottom surface 121 of the cell 12 . By effectively heating the conductive sheet 14 and the first bottom surface 121 of the cell 12, the laser device 11 can partially melt the conductive sheet 14 and the first bottom surface 121 to form a molten pool therebetween. , greatly reducing the occurrence of weld failures.

In one embodiment of the present invention, one end of the plurality of elastic units 15 can be installed on the bottom base 17 and the other end of the elastic units 15 is used to connect the cells 12 . For example, the bottom base 17 is a mounting table or a plate-like body.

In another embodiment of the present invention, one end of the elastic unit 15 can be connected to the bottom base 17, as shown in FIGS. A loading plate 151 is installed at the other end of the elastic unit 15 . In practical application, the second bottom surface 123 of the cell 12 can be placed on the loading plate 151 . Thereby, the elastic unit 15 is connected to the second bottom surface 123 of the cell 12 via the loading plate 151 . Also, the compression plate 13 compresses the elastic unit 15 via the conductive sheet 14 , the cells 12 and the stacking plate 151 . In one embodiment of the present invention, the surface of the loading plate 151 facing the crimping plate 13 may be provided with grooves to accommodate, position or temporarily fix the cells 12 .

In practical application, the loading plate 151 may be insulating and used to separate the elastic unit 15 and the cell 12 . For example, the elastic unit 15 may be made of a metal spring, and the loading plate 151 may be made of an insulating material to isolate the cell 12 and the elastic unit 15 so as to avoid the short circuit of the cell 12 .

As shown in FIGS. 5 and 6 , after the welding of the first bottom surface 121 of the cell 12 and the conductive sheet 14 is completed, the cell 12 and the conductive sheet 14 are turned over and arranged on the plurality of elastic units 15 . good too. A first bottom surface 121 of the 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 cell 12 and the crimping plate 13 can be placed on the conductive sheet 14 connected to the second bottom surface 123 of the cell 12 . The crimping plate 13 can compress the elastic unit 15 via the conductive sheet 14 and the cells 12 . This keeps the second bottom surface 123 of the cell 12 and/or each conductive sheet 14 connected to the second bottom surface 123 coplanar.

The conductive sheets 14 are in close contact with the second bottom surfaces 123 of the cells 12, and the distances between each conductive sheet 14 and the laser device 11 are approximate. Thereby, the laser beam L generated by the laser device 11 is converged on each conductive sheet 14 via the through hole 131 of the compression plate 13, and the conductive sheet 14 and the second bottom surface 123 of the cell 12 can be heated. Thus, the welding between the second bottom surface 123 of the cell 12 and the conductive sheet 14 is completed.

As shown in FIGS. 3 and 6, the battery module laser welder 10 may include a stationary frame 19 . The fixing frame 19 is located between the bottom base 17 and the crimping plate 13 and is used to fix the position of the cell 12 to prevent the cell 12 from tilting during the welding process. For example, the cells 12 are cylindrical, and the fixing frame 19 has cylindrical through holes. The area of the through-hole is slightly larger than the cross-sectional area of the cell 12 . Therefore, it is possible to fix the position of each cell 12 by arranging the cells 12 in the through holes of the fixed frame 19 .

The above are only preferred embodiments of the present invention, and are not intended to limit the implementation scope of the present invention. That is, equivalent variations and modifications based on the shape, structure, features and spirit described in the utility model claims of the present invention are all included in the utility model claims of the present invention.

10 Battery module laser welder 11 Laser device 12 Cell 121 First bottom surface 123 Second bottom surface 125 Side surface 13 Crimping plate 131 Through hole 14 Conductive sheet 15 Elastic unit 151 Loading plate 17 Bottom base 19 Fixed frame L Laser beam

Claims (7)

A battery module laser welder for welding a plurality of cells and a plurality of conductive sheets, comprising:
a laser device for generating a laser beam,
A crimping plate including a plurality of through-holes and connected to the cells through the conductive sheet, wherein the plurality of through-holes correspond to the plurality of cells, respectively, and the laser beam generated by the laser device is irradiated onto the conductive sheet through the through-holes of the crimping plate; and a plurality of elastic units facing the through-holes of the crimping plate, wherein the cell is the crimping plate. a resilient unit positioned between said through hole of said pier and said resilient unit. The cell includes a first bottom surface, a second bottom surface and a side surface, the side surface being located between the first bottom surface and the second bottom surface for connecting the first bottom surface and the second bottom surface. The battery module laser of claim 1, wherein the crimping plate is connected to the first bottom surface of the cell through the conductive sheet, and the elastic unit is connected to the second bottom surface of the cell. Welder. 3. The battery module laser welding machine of claim 2, further comprising a bottom base, wherein one end of each of the plurality of elastic units is connected to the bottom base. 4. The battery module of claim 3, further comprising a plurality of stacking plates respectively connected to the other ends of the plurality of elastic units, wherein the elastic units are connected to the second bottom surfaces of the cells via the stacking plates. laser welder. 5. The battery module laser welder of claim 4, wherein the loading plate includes grooves for receiving the cells. 4. The battery module laser welder of claim 3, further comprising a fixing frame positioned between the bottom base and the compression plate and used to fix the position of the cells. 5. The battery module laser welder of claim 4, wherein the loading plate is insulating.

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