Welding fixture

Abstract

The utility model belongs to the technical field of soft package battery manufacturing, and discloses a welding fixture. The welding clamp is used for fixing foil to be welded and comprises a base and a pressing block, the base is provided with a sliding channel, the sliding channel penetrates through the surface of the base to form an opening, the foil is arranged in the sliding channel, part of the foil extends out of the opening, and the pressing block is arranged in the sliding channel in a sliding mode so that the foil can be pressed in the sliding channel. The welding of the battery cell and the tab is simulated by using the foil, the tension test is performed on the welding position, and the welding parameters are adjusted according to the test result. According to the welding fixture, the foil can be conveniently fixed, the welding of the foil and the tab is more facilitated, the waste of materials can be reduced, and the production cost is further reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of soft-pack battery manufacturing, in particular to a welding fixture. Background Art

[0002] As a metal conductor for leading out the positive and negative electrodes of the battery cell in a soft-pack battery, the design, quality, material selection, connection process and many other aspects of the tab have a significant impact on the performance and safety of the battery. A tab with good performance can ensure efficient current transmission, reduce resistance and energy loss, and its welding or connection process needs to be precisely controlled. Due to the difference in the thickness of the battery cell or the difference in the material of the tab, the welding parameters will also be different. Before each model change, it is necessary to adjust the welding parameters and conduct a tensile test to ensure that the welding tensile force can meet the process requirements.

[0003] Currently, before conducting the welding tensile test, it is necessary to first weld the tabs of the stacked battery cells, and then conduct the test on a tensile tester, and adjust the welding parameters according to the magnitude of the welding tensile force. Since the welding parameters need to be adjusted multiple times to make the welding tensile force stable, a large number of stacked battery cells are required.

[0004] Therefore, during the detection process of the welding tensile force of the tabs of the soft-pack battery, many stacked battery cells will be scrapped, resulting in the loss of production materials and further increasing the production cost. Summary of the Utility Model

[0005] The purpose of the utility model is to provide a welding fixture, which can fix the foil material, replace the battery cell and the tab for welding and conduct the welding tensile force detection after welding, so as to reduce the waste of the battery cell, reduce the loss of production materials, and further reduce the manufacturing cost.

[0006] To achieve this purpose, the utility model adopts the following technical solutions:

[0007] A welding fixture for fixing the foil material to be welded, the welding fixture includes a base and a pressing block. The base is provided with a sliding channel, and the sliding channel penetrates to the surface of the base to form an opening. The foil material is arranged in the sliding channel, and a part of the foil material extends out of the opening. The pressing block is slidably arranged in the sliding channel to press the foil material in the sliding channel.

[0008] As an optional solution of the welding fixture, the sliding channel includes a supporting surface and a driving surface spaced from the supporting surface. The supporting surface is configured to support the foil material, and along the direction in which the pressing block slides into the sliding channel, the distance between the driving surface and the supporting surface gradually decreases.

[0009] As an alternative to the welding fixture, the pressing block has a sliding mating surface that matches the driving surface. When the pressing block slides into the sliding channel, the sliding mating surface fits against the driving surface, and the inclination angles of the sliding mating surface and the driving surface are the same.

[0010] As an alternative to the welding fixture, an adjustment channel that penetrates to the surface of the base is provided on the inner wall of the sliding channel to adjust the pressing block, and the opening communicates with the adjustment channel.

[0011] As an alternative to the welding fixture, the pressing block has a sliding portion, and both ends of the sliding portion are slidably engaged with the adjustment channel.

[0012] As an alternative to the welding fixture, the sliding portion is provided with a finger groove or a handle to adjust the position of the pressing block.

[0013] As an alternative to the welding fixture, the base is provided with more than two sliding channels, and a pressing block is slidably arranged in each sliding channel. The sliding channels are respectively used to fix the positive electrode foil and the negative electrode foil.

[0014] As an alternative to the welding fixture, the opening widths of more than two sliding channels are different.

[0015] As an alternative to the welding fixture, the base includes a top plate and a bottom plate. A groove extending inward is provided on the side wall of the top plate. The top plate and the bottom plate are detachably connected, and the groove and the bottom plate form the sliding channel.

[0016] As an alternative to the welding fixture, the base is provided with weight-reducing holes.

[0017] Advantages of the present utility model:

[0018] The purpose of this solution is to provide a welding fixture. The welding fixture can fix the foil in the sliding channel through the pressing block, and a part of the foil extends out of the sliding channel to simulate the part on the electrode tab of the battery cell for welding the electrode ear. The whole welding fixture is placed on the working station for welding the battery cell with the electrode ear, and then the foil and the electrode ear can be pulled apart by the detection device to observe the remaining area and the magnitude of the pulling force at the welding point, so as to adjust the parameters of the welding equipment.

[0019] Adjust the parameters of the welding equipment according to the welding situation of the foil and the electrode ear. After the parameters of the welding equipment are adjusted in place, it can be directly used to weld the electrode tab and the electrode ear of the battery cell, avoiding the scrapping of the battery cell caused by adjusting the parameters with the battery cell, saving materials, and thus reducing the production cost. Description of the Drawings

[0020] Figure 1 is an isometric view of a welding fixture of the present utility model;

[0021] Figure 2 is the top view of a welding jig of the present utility model;

[0022] Figure 3 is the axonometric view of the base of a welding jig of the present utility model;

[0023] Figure 4 is the axonometric view of the top plate of a welding jig of the present utility model;

[0024] Figure 5 is the axonometric view of the pressing block of a welding jig of the present utility model.

[0025] In the figure:

[0026] 1 - Base; 11 - Top plate; 12 - Bottom plate; 13 - Sliding channel; 14 - Adjusting channel; 15 - Weight reduction hole; 16 - Opening; 111 - Groove; 131 - Support surface; 132 - Driving surface;

[0027] 2 - Pressing block; 21 - Sliding mating surface; 22 - Sliding part; 221 - Finger grip groove;

[0028] 3 - Foil; 31 - Positive foil; 32 - Negative foil. Specific embodiments

[0029] The present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the present utility model, rather than limiting the present utility model. Additionally, it should be noted that for the sake of description, only parts related to the present utility model are shown in the drawings, rather than all structures.

[0030] In the description of the present utility model, unless otherwise clearly defined and limited, the terms "connected", "connected to", and "fixed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0031] In the present utility model, unless otherwise clearly defined and limited, the first feature being "above" or "below" the second feature may include the first and second features being in direct contact, or may include the first and second features not being in direct contact but being in contact through other features therebetween. Moreover, the first feature being "above", "above and to the right", and "on top of" the second feature includes the first feature being directly above and diagonally above the second feature, or merely indicating that the first feature has a higher horizontal height than the second feature. The first feature being "below", "below and to the left", and "beneath" the second feature includes the first feature being directly below and diagonally below the second feature, or merely indicating that the first feature has a lower horizontal height than the second feature.

[0032] In the description of this embodiment, the orientation or positional relationships such as "upper", "lower", "right", etc. are based on the orientation or positional relationships shown in the drawings. It is only for the convenience of description and simplifying the operation, rather than indicating or implying that the device or component referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present utility model.

[0033] A battery cell is usually composed of parts such as a positive electrode plate, a negative electrode plate, a separator, and an electrolyte. The electrode plate is an important component of the battery cell. The positive electrode plate and the negative electrode plate are key components for realizing the storage and release of electric energy. During the charging and discharging process of the battery, ions migrate between the positive and negative electrode plates, and the mutual conversion between electric energy and chemical energy is achieved through chemical reactions. It can be said that the performance and quality of the electrode plate directly affect the performance of the battery cell. High-quality electrode plates can provide better electrical conductivity, stability, and chemical activity, thus enabling the battery cell to have more excellent comprehensive performance.

[0034] This embodiment provides a welding fixture for fixing the foil 3 to be welded. Specifically, this welding fixture can be placed on the working station for tab welding to simulate the battery cell with the tab to be welded. The foil 3 is the part on the simulated electrode plate for welding the tab. Therefore, the material and thickness of the foil 3 are the same as those of the part of the electrode plate on the battery cell for welding the tab. Usually, the welding part between the electrode plate and the tab is the part where the current collector metal foil that is not covered by the active material on the electrode plate extends (such as aluminum foil or copper foil, etc.). In order to simulate the welding effect of multiple electrode plates and tabs, the foil 3 can be several pieces of metal foil, or multiple pieces of metal foil are folded into multiple layers to the required thickness.

[0035] As Figures 1-3 shown, this welding fixture includes a base 1 and a pressing block 2. A sliding channel 13 is provided on the base 1. One end of the sliding channel 13 penetrates to the surface of the base 1 to form an opening 16. The length of the sliding channel 13 is set according to the size of the foil 3 without further limitation. In order to prevent the foil 3 from slipping out of the base 1, the other end of the sliding channel 13 is closed. The foil 3 is arranged in the sliding channel 13, and a part of the foil 3 extends out of the opening 16 of the sliding channel 13. The part of the foil 3 extending out of the opening 16 is convenient for welding with the tab. The pressing block 2 is arranged in the sliding channel 13 to press the foil 3 in the sliding channel 13. Specifically, the shape of the sliding channel 13 is a cube with an opening 16 on one side. After the foil 3 is placed in the sliding channel 13, the pressing block 2 is inserted into the sliding channel 13. At this time, the foil 3 is located below the pressing block 2, and the pressing block 2 is pushed inward until it cannot be pushed anymore, locking the foil 3 to realize the fixation of the foil 3 to be welded.

[0036] The pressing block 2 secures the foil 3 within the sliding channel 13. The portion of the foil 3 extending from the sliding channel 13 is used for welding to the tab. After welding, the foil 3 and the tab can be separated using inspection equipment to observe the residual area at the weld and the amount of tension, thereby adjusting the parameters of the welding equipment. The tab can be placed manually, by a robotic arm, or by conveyor belt transport, as long as the tab's stability during welding is guaranteed.

[0037] The parameters of the welding equipment are adjusted according to the welding conditions of the foil 3 and the tab. After the parameters of the welding equipment are adjusted, it can be directly used to weld the electrode and the tab of the battery cell, avoiding the battery cell being scrapped due to damage to the electrode, saving materials and reducing costs.

[0038] Further, if Figure 3 and Figure 4 As shown, the sliding channel 13 includes a support surface 131 and a driving surface 132 spaced apart from the support surface 131 . The support surface 131 is configured to support the foil 3 , and the driving surface 132 is a contact surface for promoting the movement of the pressing block 2 .

[0039] In some embodiments, the driving surface 132 is parallel to the supporting surface 131, and the sum of the thickness of the pressing block 2 and the thickness of the foil 3 is equal to the distance between the supporting surface 131 and the driving surface 132. When one end of the pressing block 2 is in contact with the closed end opposite to the opening 16, the pressing block 2 slides and locks the foil 3 in the sliding channel 13. At this time, the extrusion force generated on the foil 3 is relatively small, which also facilitates the removal of the foil 3 after the subsequent welding is completed.

[0040] In some embodiments, the driving surface 132 is parallel to the supporting surface 131, and when the sum of the thickness of the pressing block 2 and the thickness of the foil 3 is greater than the distance between the supporting surface 131 and the driving surface 132, the pressing block 2 and the sliding channel 13 are interference fit to fix the foil 3 in the sliding channel 13. At this time, the foil 3 is subjected to a larger extrusion force to ensure that the foil 3 will not fall out of the sliding channel 13, thereby improving the accuracy of the test results.

[0041] In some embodiments, along the direction in which the pressing block 2 slides into the sliding channel 13, the distance between the driving surface 132 and the supporting surface 131 gradually decreases. Due to different battery thicknesses or different tab materials, different welding parameters are required. When the foil 3 is used instead of the battery cell for the tensile test, the thickness of the foil 3 and the thickness of the tab need to correspond one by one. Since the distance between the driving surface 132 and the supporting surface 131 gradually decreases, when pressing the foil 3 with different thicknesses, the sliding amount of the pressing block 2 sliding into the sliding channel 13 is also different. As the thickness of the foil 3 increases, the sliding amount of the pressing block 2 sliding into the sliding channel 13 gradually decreases. That is to say, the pressing block 2 can adjust the pressing force on the foil 3 and the adaptability to the thickness of the foil 3 by the distance of entering the sliding channel 13, and can be applicable to the fixation of foils 3 with various thicknesses. When the pressing block 2 slides into the sliding channel 13, the front edge of the pressing block 2 contacts the driving surface 132, the bottom surface of the pressing block 2 presses the foil 3, and the pressing block 2 locks the foil 3. At this time, the processing technology of the pressing block 2 is simple.

[0042] Further, as Figure 5 shown, the pressing block 2 has a sliding surface 21 that matches the driving surface 132. When the pressing block 2 slides into the sliding channel 13, the sliding surface 21 fits with the driving surface 132. The pressing block 2 and the driving surface 132 are always in surface contact, with uniform force, easy to slide and lock, and the bottom surface angle of the pressing block 2 is stable.

[0043] The inner wall of the sliding channel 13 is provided with an adjustment channel 14 that penetrates to the surface of the base 1 to adjust the pressing block 2, and the opening 16 is communicated with the adjustment channel 14. The setting of the adjustment channel 14 facilitates the operation of the pressing block 2, making it more convenient for the pressing block 2 to slide into and out of the sliding channel 13.

[0044] In some embodiments, the adjustment channel 14 penetrates from the side of the sliding channel 13 to the surface of the base 1, and the opening 16 is communicated with the adjustment channel 14. At this time, the entire upper surface of the pressing block 2 is subjected to the driving force of the driving surface 132, so that the pressing force of the pressing block 2 on the foil 3 can be evenly distributed on the foil 3.

[0045] The adjustment channel 14 penetrates from the driving surface 132 to the upper surface of the base 1, and the opening 16 is communicated with the adjustment channel 14. The adjustment channel 14 and the sliding channel 13 are combined together to present a T shape. Specifically, as Figure 3 described, the adjustment channel 14 is located above the sliding channel 13 and is connected to the opening 16 of the sliding channel 13. One sliding channel 13 is provided with two driving surfaces 132, which are respectively located on the left and right sides of the adjustment channel 14. This structure makes the driving forces of the sliding channel 13 received by the pressing block 2 symmetrically distributed, so that the pressing force of the pressing block 2 on the foil 3 is evenly distributed on the foil 3, and it can avoid excessive local force on the foil 3 and tearing while ensuring the pressing of the foil 3.

[0046] AsFigure 5 As shown in the figure, the pressing block 2 has a sliding portion 22. Both ends of the sliding portion 22 are in sliding fit with the adjusting channel 14, which can ensure that the pressing block 2 does not move laterally or rotate within a small range when sliding in the sliding channel 13, improving the stability of the pressing block 2 and avoiding adverse effects such as wrinkling of the multi-layer foil 3 caused by lateral friction between the pressing block 2 and the foil 3 after pressing. It can also ensure that the sliding mating surface 21 and the driving surface 132 always maintain surface contact, thereby avoiding an increase in the local pressure of the pressing block 2 on the foil 3 and affecting the detection result of the subsequent welding tensile force.

[0047] In this embodiment, as Figure 1 shown, the pressing block 2 is in a T shape, and the side surface of the pressing block 2 fits with the sliding channel 13 to further improve the guiding property of the sliding channel 13 for the pressing block 2.

[0048] To facilitate the removal of the pressing block 2, the sliding portion 22 is provided with a handle groove 221 or a handle (not shown in the figure) to adjust the position of the pressing block 2. The operator can operate the pressing block 2 through the handle groove 221 or the handle to make the pressing block 2 slide in the sliding channel 13. When the sliding portion 22 is provided with a handle groove 221, the number, position, and shape of the handle groove 221 are not unique. When the number of the handle grooves 221 is one, it can be arranged at the center position of the sliding portion 22 or at the edge position around the sliding portion 22; when the number of the handle grooves 221 is two, the handle grooves 221 can be symmetrically arranged; the shape of the handle groove 221 can be rectangular, triangular, U-shaped, etc. When the sliding portion 22 is provided with a handle, the handle forms a protrusion on the sliding portion 22, and the direction of the handle is consistent with the sliding direction of the pressing block 2. In this embodiment, the handle groove 221 is arranged along the direction of the sliding channel 13, and two U-shaped handle grooves 221 are formed on the upper surface of the sliding portion 22, and the two U-shaped handle grooves 221 are symmetrically arranged, which is convenient for the pressing block 2 to slide into and out of the sliding channel 13.

[0049] As Figure 3As shown in the figure, further, the base 1 includes a top plate 11 and a bottom plate 12. A groove 111 extending inward is formed on the side wall of the top plate 11. The groove 111 and the upper surface of the bottom plate 12 form a sliding channel 13. When the number of sliding channels 13 is more than two, they can be arranged on the same side of the top plate 11 along the direction of the opening 16, or symmetrically arranged on both sides of the top plate 11, or arranged around the top plate 11, making full use of the space of the base 1. The top plate 11 and the bottom plate 12 are detachably connected, such as by bolt connection or snap connection. If there is a situation where the pressing block 2 and the foil 3 are squeezed too tightly, making it difficult to take them out smoothly, the top plate 11 and the bottom plate 12 can be disassembled, so as to smoothly take out the pressing block 2 and the foil 3. On the other hand, compared with the integrally formed base 1, the detachable top plate 11 and bottom plate 12 have a simple structure. If an integrally formed base 1 is used, it may require higher precision and complex molds or processes, resulting in higher costs. While the detachable base 1 decomposes the structure into relatively simple components for separate manufacturing, reducing the production difficulty and cost.

[0050] In this embodiment, the base 1 is provided with weight-reducing holes 15. By reasonably arranging the weight-reducing holes 15 on the base 1, the use of materials for the base 1 can be reduced, thereby reducing the overall weight of the welding fixture. It should be noted that the number, shape, and position of the weight-reducing holes 15 are not unique and can be designed according to needs. Specifically, in this embodiment, as Figures 1-3 shown, two circular through holes are provided on the upper surface of the base 1 as the weight-reducing holes 15 of the welding fixture.

[0051] Generally speaking, a battery cell includes a positive electrode tab and a negative electrode tab, and both the positive electrode tab and the negative electrode tab need to be subjected to a tensile test. In the embodiment of the present invention, the sliding channel 13 on the base 1 can be one or more, and correspondingly, the pressing block 2 can also be one or more. The number of pressing blocks 2 corresponds to the number of sliding channels 13.

[0052] When the sliding channel 13 is set to one, the welding fixture can successively perform the welding and tensile test of the positive electrode tab and the negative electrode tab; when the sliding channel 13 is set to two, the welding fixture can simultaneously perform the welding and tensile test of the positive electrode tab and the negative electrode tab; when the sliding channel 13 is set to three or more, the welding and tensile test of the tabs of battery cells of different specifications can be simultaneously performed. Since the operation method of the welding fixture is the same and has nothing to do with the number of sliding channels 13 and pressing blocks 2, no specific examples are given here.

[0053] Next, refer to Figures 1-2 to describe a welding fixture according to a specific embodiment of the present invention, which is used to simultaneously weld the positive electrode tab and the negative electrode tab.

[0054] The base 1 is provided with two sliding channels 13 for fixing the positive electrode foil 31 and the negative electrode foil 32 respectively. A pressing block 2 is slidably arranged in each sliding channel 13. The upper surface of the base 1 has positive and negative markings to distinguish the two sliding channels 13. In order to prevent the two pressing blocks 2 from being placed in the wrong position during use, resulting in the foil 3 not being tightly pressed, the openings 16 of the two sliding channels 13 are set to different widths for easy distinction. First, the positive electrode foil 31 and the negative electrode foil 32 are placed into the corresponding sliding channels 13, and a part of the foil 3 extends out of the opening 16 of the sliding channel 13. Then, through the adjustment channel 14 formed on the surface of the base 1, using the buckle grooves 221 on the sliding parts 22 of the pressing blocks 2, the two pressing blocks 2 are respectively slid into the sliding channels 13 with corresponding sizes, and the pressing blocks 2 are pushed inward until they cannot be pushed, so as to lock and fix the positive electrode foil 31 and the negative electrode foil 32. Finally, the electrode tabs and the foil 3 are welded. After the welding is completed, the welding tensile strength is detected.

[0055] Obviously, the above-mentioned embodiments of the present invention are only examples for clearly illustrating the present invention, rather than limiting the implementation manners of the present invention. For those of ordinary skill in the art, various obvious changes, re-adjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to list all the implementation manners here. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the claims of the present invention.

Claims

1. A welding fixture for fixing a foil (3) to be welded, characterized in that, The welding fixture includes a base (1) and a pressing block (2). The base (1) is provided with a sliding channel (13), and the sliding channel (13) penetrates to the surface of the base (1) to form an opening (16). The foil (3) can be arranged in the sliding channel (13) and partially protrudes from the opening (16). The pressing block (2) is slidably arranged in the sliding channel (13) to press the foil (3) in the sliding channel (13).

2. The welding jig according to claim 1, wherein The sliding channel (13) includes a supporting surface (131) and a driving surface (132) spaced from the supporting surface (131). The supporting surface (131) is configured to support the foil (3). Along the direction in which the pressing block (2) slides into the sliding channel (13), the distance between the driving surface (132) and the supporting surface (131) gradually decreases.

3. The welding jig according to claim 2, characterized in that, The pressing block (2) has a sliding mating surface (21) matching the driving surface (132). When the pressing block (2) slides into the sliding channel (13), the sliding mating surface (21) fits with the driving surface (132), and the inclination angles of the sliding mating surface (21) and the driving surface (132) are the same.

4. The welding jig according to claim 1, wherein, An adjusting channel (14) penetrating to the surface of the base (1) is formed in the inner wall of the sliding channel (13) to adjust the pressing block (2), and the opening (16) is communicated with the adjusting channel (14).

5. The welding jig according to claim 4, wherein The pressing block (2) has a sliding portion (22), and both ends of the sliding portion (22) are slidably mated with the adjusting channel (14).

6. The welding jig according to claim 5, wherein, The sliding portion (22) is provided with a finger groove (221) or a handle to adjust the position of the pressing block (2).

7. The welding jig according to any one of claims 1-6, characterized in that, The base (1) is provided with more than two sliding channels (13). The pressing block (2) is slidably arranged in each sliding channel (13). The sliding channels (13) are respectively used to fix the positive electrode foil (31) and the negative electrode foil (32).

8. The welding jig according to claim 7, wherein The widths of the openings (16) of more than two sliding channels (13) are different.

9. The welding jig according to any one of claims 1-6, characterized in that The base (1) includes a top plate (11) and a bottom plate (12). A groove (111) extending inward is formed in the side wall of the top plate (11). The top plate (11) and the bottom plate (12) are detachably connected, and the groove (111) and the bottom plate (12) form the sliding channel (13).

10. The welding jig according to any one of claims 1-6, characterized in that, A weight reduction hole (15) is provided on the base (1).

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