Cylindrical battery tab welding quality detection tool and welding quality detection method

Abstract

The invention relates to the technical field of battery production and manufacturing, in particular to a cylindrical battery tab welding quality detection tool and a welding quality detection method.The cylindrical battery tab welding quality detection tool comprises a cylindrical shell, the diameter of the shell is matched with the inner diameter of a steel shell, one end of the cylindrical shell is open, and the other end of the cylindrical shell is provided with an end plate; a welding needle hole is formed in the middle of the end plate, a lug hole is formed in the edge of the end plate, the lug penetrates through the lug hole from the interior of the cylindrical shell and extends to the exterior of the end plate, and the welding needle hole is covered with the lug. According to the method for detecting the welding quality of the cylindrical battery pole lug, the pole lug penetrates through the detection tool to be fixed, is loaded into the steel shell, is welded and then is subjected to pulling force, the pole lug is snapped, whether the pole lug is left on the steel shell or not is checked, efficient detection of the welding quality of the pole lug and the steel shell is achieved, the detection efficiency and reliability are effectively improved, and the detection cost is reduced. And meanwhile, the problems of inconvenience in operation and potential safety hazards caused by using scrapped battery cells in a traditional method are avoided.

Description

Technical Field

[0001] The present application relates to the technical field of battery production and manufacturing, and in particular to a cylindrical battery tab welding quality detection tooling and a welding quality detection method. Background Art

[0002] The process preparation technology of cylindrical batteries mainly includes a front-end process of sheet preparation, a middle-end process of assembly, and a back-end process of testing. The front-end process of sheet preparation generally includes pulping, coating, rolling, slitting, and sheet making. The middle-end process of assembly generally includes winding, casing insertion, grooving, cover plate welding, baking, liquid injection, etc.; the back-end process of testing generally includes formation, grading, detection, and sorting, etc.

[0003] Among them, in the middle-end process of assembly, winding refers to assembling a battery cell by winding a positive electrode sheet, a negative electrode sheet, and a separator through a winding machine; casing insertion refers to placing upper and lower insulating gaskets, bending the tabs, putting the wound core and the insulating gasket into the steel shell, and at the same time using resistance welding to weld the negative tab to the bottom of the steel shell, so that the entire steel shell is negatively charged; and cover plate welding is to connect the positive tab with the battery cover plate by laser welding, so that the cover plate forms a positive electrode.

[0004] In order to ensure the quality of the battery, during subsequent detection and sorting, it is necessary to detect the welding quality of the tabs with the steel shell and the tabs with the cover plate. The currently commonly used detection method is that during the production of the first piece, the tabs used in the production of the battery cells are sleeved on the scrapped battery cells, put into the steel shell, the tabs are bottom-welded to the bottom of the steel shell, and after welding, the scrapped battery cells are taken out of the steel shell, and then a specific device is used to apply a pulling force to the steel shell and the tabs, and the welding strength of the steel shell and the tabs is detected by testing the pulling force value. For those that meet the process standards, normal production is carried out. For those that do not meet the process standards, they will be re-detected according to this method. If they are still unqualified, the welding parameters will be adjusted and the welding pulling force will be re-detected.

[0005] However, since the diameter of the scrapped battery cell is usually correspondingly matched with the inner diameter of the steel shell, after the tab is sleeved on the scrapped battery cell, the diameter of the battery cell will increase, making it difficult to put it into the steel shell, and it is also inconvenient to take it out after the battery cell is put into the steel shell. Therefore, it is necessary to find a scrapped battery cell with a suitable size, and this process will inevitably waste a lot of time and energy.

[0006] In addition, the scrapped battery cells are likely to be left in the steel shell and enter the subsequent production process, resulting in unqualified batteries, with relatively large potential hazards.

[0007] Moreover, since the detection of tab welding quality takes a certain amount of time, the production line will be in a stopped state during the process, and subsequent production can only be carried out after waiting for the detection to be qualified. Therefore, a large amount of production man-hours are wasted. Summary of the Invention

[0008] This application provides a jig for detecting the welding quality of the tabs of cylindrical batteries.

[0009] In the first aspect, a jig for detecting the welding quality of the tabs of cylindrical batteries provided by this application adopts the following technical solutions: A jig for detecting the welding quality of the tabs of cylindrical batteries includes a cylindrical shell, the diameter of the shell is matched with the inner diameter of the steel shell, one end of the cylindrical shell is open, and the other end is provided with an end plate; a welding needle hole is opened at the middle position of the end plate, and an ear hole is opened at the edge position. The tab passes through the ear hole from inside the cylindrical shell and extends to the outside of the end plate, and the tab covers the welding needle hole.

[0010] By adopting the above technical solutions, the jig is provided with a cylindrical shell that matches the inner diameter of the steel shell, and a welding needle hole and an ear hole are opened on the end plate, so that the tab can pass through the ear hole and cover the welding needle hole, thus replacing the traditional scrapped battery cells for welding quality detection. This solution effectively solves the problem that it is difficult to put in and take out the scrapped battery cells, avoids wasting time and energy in searching for suitable scrapped battery cells, and at the same time reduces the risk of production hazards caused by the omission of scrapped battery cells in the steel shell, improving the detection efficiency and production safety.

[0011] Preferably, it further includes a fixing mechanism for fixing the tab; the fixing mechanism includes a fixing frame arranged inside the shell and a first fixing clip arranged on the fixing frame; a first through hole is opened on the fixing frame for the tab to pass through, and the first fixing clip thus clamps and fixes the tab.

[0012] By adopting the above technical solutions, the first through hole opened on the fixing frame allows the tab to pass through, and the first fixing clip can clamp and fix the tab. This design ensures that the tab remains stable during the detection process, avoids inaccurate detection results caused by the loosening or displacement of the tab, and thus improves the reliability and consistency of the welding quality detection.

[0013] Preferably, fixing holes are further opened at the edge of the end plate, and second through holes corresponding to the fixing holes are opened on the fixing frame; the fixing mechanism further includes a second fixing clip arranged on the fixing frame. The tab passes through the fixing hole and the second through hole from outside the shell, and is fixed by the second fixing clip.

[0014] By adopting the above technical solutions, the tab can pass through the fixing hole and the second through hole from outside the shell and is fixed by the second fixing clip, thereby realizing the firm clamping of the tab. This design effectively avoids the displacement of the tab during the welding process, ensures the accuracy of the welding position, and further improves the reliability of the welding quality detection. At the same time, by arranging the fixing holes at the edge of the end plate and the corresponding second through holes, the installation operation of the tab is simplified, and the usability of the detection jig is improved.

[0015] Preferably, the fixing bracket is slidably connected to the housing, and the fixing bracket is movable along the length direction of the housing.

[0016] By adopting the above technical solution, the fixing position of the tab can be adjusted according to actual needs, thereby improving the adaptability of the detection tooling. During the welding quality detection process, this adjustability helps to ensure that the tab is in the best stress state, facilitating the guarantee of welding quality. In addition, this design also facilitates the installation and disassembly of the tab, improving the convenience of operation.

[0017] Preferably, both the first fixing clip and the second fixing clip are provided with operation buttons, operation holes are formed in the side wall of the housing, and the operation buttons are arranged at the operation holes.

[0018] By adopting the above technical solution, the operator can conveniently control the opening and closing state of the fixing clip by pressing the operation button, thereby realizing the quick fixing and release of the tab and improving the detection efficiency.

[0019] Preferably, when the operation button is located at the operation hole, the operation button extends into the operation hole and makes the first fixing clip and the second fixing clip in a clamping state; when the fixing bracket moves in the housing, the operation button contracts under the extrusion of the side wall of the housing to make the first fixing clip and the second fixing clip in an open state.

[0020] By adopting the above technical solution, when the operation button is located at the operation hole, the operation button extends into the operation hole and makes the first fixing clip and the second fixing clip in a clamping state, thereby ensuring that the tab is firmly fixed during the detection process, and through the cooperation of the operation button and the operation hole, the fixing bracket can be fixed to ensure the stability of the fixing bracket and the tab. When the fixing bracket moves in the housing, the operation button contracts under the extrusion of the side wall of the housing, so that the first fixing clip and the second fixing clip are in an open state, facilitating the installation and disassembly of the tab and improving the detection efficiency.

[0021] Preferably, a first plug inserted into the tab hole and a second plug inserted into the fixing hole are arranged on the fixing bracket, and both the first plug and the second plug are tubular; the first plug communicates with the first through hole, and the second plug communicates with the second through hole for the tab to pass through.

[0022] By adopting the above technical solution, the arrangement of the first plug and the second plug can ensure the stability of the tab when passing through the tab hole and the fixing hole, avoiding the tab from shifting or twisting during the operation. The design that the first plug communicates with the first through hole and the second plug communicates with the second through hole further improves the reliability of the tab fixing, enabling the tab to be accurately positioned on the welding needle hole during the detection process, thereby improving the accuracy and efficiency of the welding quality detection.

[0023] Preferably, the housing includes a large-diameter section and a small-diameter section. The outer diameter of the large-diameter section is equal to the inner diameter of the steel shell, and the small-diameter section is coaxially arranged with the large-diameter section. There is a stepped surface between the large-diameter section and the small-diameter section. Both the tab hole and the fixing hole penetrate through the large-diameter section and form openings on the stepped surface. The fixing part is arranged inside the large-diameter section.

[0024] By adopting the above technical solution, the outer diameter of the large-diameter section matches the inner diameter of the steel shell, which can ensure the stability of the detection tooling. At the same time, the openings of the tab hole and the fixing hole are formed by the stepped surface, which is convenient for quickly threading and fixing the tab, improving the operation efficiency. The design of the small-diameter section helps with holding and is convenient for operation.

[0025] Preferably, a top plate is provided at one end of the small-diameter section away from the large-diameter section, and the diameter of the top plate is the same as the diameter of the large-diameter section.

[0026] By adopting the above technical solution, the diameter of the top plate is the same as the diameter of the large-diameter section, which can form good support inside the steel shell, ensure the stability of the detection process, and prevent the detection tooling from accidentally shifting due to external forces.

[0027] On the other hand, the present application provides a method for detecting the welding quality of cylindrical battery tabs, using the above-mentioned cylindrical battery tab welding quality detection tooling; it includes the following steps: Thread the tab used when producing the first-piece production battery cell through the detection tooling for fixing, and then install it into the steel shell used when producing the battery cell, and directly weld. Apply a pulling force to the tab and break the tab, check whether there is any residue of the tab on the steel shell. If there is residue, the welding strength meets the requirements. If there is no residue, adjust the welding parameters and retest; at the same time, test the welding pulling force to digitalize the welding pulling force data.

[0028] By adopting the above technical solution, an efficient method for detecting the welding quality of cylindrical battery tabs is provided. This method uses a dedicated detection tooling, avoiding the inconvenience and potential hazards brought by using scrapped battery cells in the traditional method, significantly improving the detection efficiency and accuracy. The method is simple and easy to operate, reducing the downtime of the production line and improving the overall production efficiency. In summary, the present invention includes at least one of the following beneficial technical effects: 1. By using a cylindrical housing to replace the scrapped battery cell, the diameter of the housing matches the inner diameter of the steel shell, avoiding the problem of increased size caused by the tab being sleeved on the scrapped battery cell, thus significantly improving the operational convenience of inserting the tab into the steel shell. 2. The tab extends to the outside through the tab hole on the end plate and covers the welding needle hole, ensuring the stability and reliability of the welding process. At the same time, it is convenient for subsequent pulling force testing, effectively avoiding the potential safety hazard that the scrapped battery cell may remain in the steel shell in the traditional method. 3. The entire detection tooling has a simple structure and fast operation. There is no need to pause the production line to wait for the disposal of scrapped battery cells, significantly shortening the detection cycle, improving production efficiency, and reducing production costs. Description of the Drawings

[0029] Figure 1 is the overall structural schematic diagram of the cylindrical battery tab welding quality detection tooling in Embodiment 1 of the present application; Figure 2 is the overall structural schematic diagram of the cylindrical battery tab welding quality detection tooling after adding a fixing mechanism and fixing holes in Embodiment 1 of the present application; Figure 3 is the cross-sectional view of the cylindrical battery tab welding quality detection tooling in Embodiment 1 of the present application; Figure 4 is the structural schematic diagram of the cylindrical battery tab welding quality detection tooling in Embodiment 2 of the present application; Figure 5 is the structural schematic diagram of the cylindrical battery tab welding quality detection tooling from another perspective in Embodiment 2 of the present application.

[0030] Reference numerals in the drawings: 1, housing; 11, operation hole; 12, large-diameter section; 13, small-diameter section; 14, top plate; 2, end plate; 21, welding needle hole; 22, tab hole; 23, fixing hole; 3, fixing mechanism; 31, fixing frame; 311, first through hole; 312, second through hole; 313, first plug; 314, second plug; 32, first fixing clip; 33, second fixing clip; 34, operation button. Detailed Description of the Embodiments

[0031] The following further elaborates on the present invention Figures 1-5 in conjunction with the appended drawings.

[0032] Embodiment 1 The cylindrical battery tab welding quality detection tooling provided by the embodiment of the present application includes a cylindrical housing 1 and an end plate 2. Specifically, the cylindrical housing 1 is made of a metal material, having high strength and wear resistance. Its outer shape is cylindrical, and the diameter is precisely matched with the inner diameter of the steel shell to ensure that it can be smoothly inserted into the steel shell. One end of the cylindrical housing 1 is open, and an end plate 2 is provided at the other end. The end plate 2 and the housing 1 can be integrally formed, or can be connected by welding, screwing, etc. A welding needle hole 21 is opened in the middle of the end plate 2 for welding operations; tab holes 22 are opened at the edge position of the end plate 2 for the tabs to pass through.

[0033] When the detection tooling is in use, the tab is passed through the tab hole 22 inside the housing 1 and extends to the surface of the end plate 2, covering the surface of the welding hole. The tab can be fixed with adhesive tape. Subsequently, the detection tooling can be installed in the battery steel shell and subsequent welding operations such as bottom welding and cover plate welding can be carried out.

[0034] In order to further improve the fixing effect of the tab, ensure that the tab does not shift in position before and after welding, and facilitate ensuring the welding quality, the cylindrical battery tab welding quality detection tooling of the embodiment of the present application further adds a fixing mechanism 3. The fixing mechanism 3 includes a fixing frame 31 and a first fixing clip 32. The fixing frame 31 is made of aluminum alloy material, which is light and strong, and is fixed inside the housing 1. A first through hole 311 is provided on the fixing frame 31, and the first through hole 311 is opposite to and communicates with the tab hole 22, so that the tab can pass through the first through hole 311 and the tab hole 22 in sequence. The first fixing clip 32 adopts a spring clip structure and is made of stainless steel material, having good heat resistance and corrosion resistance. The first fixing clip 32 can clamp and fix the tab passing through the first through hole 311.

[0035] In order to further improve the fixing effect, fixing holes 23 are further provided at the edge of the end plate 2. The fixing holes 23 can be symmetrically arranged with the tab holes 22 centered on the end plate 2. And, in the embodiment of the present application, the tab holes 22 and the fixing holes 23 can be used interchangeably.

[0036] A second through hole 312 is also provided on the fixing frame 31, corresponding to the fixing holes 23 on the end plate 2. The fixing mechanism 3 further includes a second fixing clip 33, which also adopts a spring clip structure. After the tab passes through the fixing holes 23 and the second through hole 312 in sequence from the outside of the housing 1, it is secondarily fixed by the second fixing clip 33. This double fixing method can effectively prevent the tab from shifting during welding and ensure the welding quality.

[0037] A first plug 313 and a second plug 314 are also provided on the fixing frame 31, both of which are in a tubular structure. The first plug 313 communicates with the first through hole 311 and is used to guide the tab to pass through; the second plug 314 communicates with the second through hole 312 and is used to further fix the tab.

[0038] The first plug 313 can be inserted and matched with the tab hole 22, while the second plug 314 can be inserted and matched with the fixing hole 23, so that the tab can pass through the tab hole 22 and the fixing hole 23 smoothly. In addition, it can effectively position the fixing frame 31 and ensure the stability of the fixing frame 31.

[0039] Further, both the first fixing clip 32 and the second fixing clip 33 are equipped with operation buttons 34. An operation hole 11 is provided on the side wall of the housing 1, and the operation buttons 34 are arranged at the operation hole 11.

[0040] In addition, the fixing bracket 31 can also be slidably connected to the housing 1 through a slide rail structure, and the fixing bracket 31 can move freely along the length direction of the housing 1. Thus, when the operation button 34 is located at the operation hole 11, the button extends into the operation hole 11. At this time, the first fixing clip 32 and the second fixing clip 33 are in a clamping state, firmly fixing the tab, and through the cooperation of the operation button 34 and the operation hole 11, the fixing bracket 31 is limited, ensuring the stability of the fixing bracket 31. When moving the fixing bracket 31, press the operation button 34 to retract it into the interior of the housing 1, and then the fixing bracket 3 slides along the inner wall of the housing 1. At the same time, the operation button 34 automatically contracts under the extrusion of the side wall of the housing 1, making the first fixing clip 32 and the second fixing clip 33 in an open state, facilitating the adjustment of the tab position.

[0041] In addition, in order to facilitate the movement of the fixing bracket 31, a push rod can be additionally used to push the fixing bracket 31 by passing the nail rod through the welding needle hole 21 or the interior of the housing 1.

[0042] The implementation principle of this embodiment is as follows: The design of the operation button 34 simplifies the operation process of fixing and loosening the tab, improving work efficiency. The addition of the top plate 14 not only plays a limiting role but also enhances the structural stability of the entire device. The segmented design of the large-diameter section 12 and the small-diameter section 13 enables the device to maintain a good fit with the steel shell while also facilitating manufacturing and assembly. These improvement measures further enhance the practicality and reliability of the device.

[0043] Embodiment Two The difference between the embodiment of the present application and Embodiment One lies in: the structure of the housing 1 is different.

[0044] Specifically, the housing 1 includes a large-diameter section 12 and a small-diameter section 13, which are coaxially arranged, and there is a step surface between the large-diameter section 12 and the small-diameter section 13. The outer diameter of the large-diameter section 12 is equal to the inner diameter of the steel shell and is used to insert into the steel shell. One end of the small-diameter section 13 away from the large-diameter section 12 is provided with a top plate 14, and the diameter of the top plate 14 is the same as the diameter of the large-diameter section 12, which can abut against the inner wall of the steel shell to play a limiting role. Importantly, the top plate 14 is provided with an opening for the tab to pass through, so as to facilitate the welding of the tab and the cover plate.

[0045] The fixing bracket 31 is arranged inside the large-diameter section 12, and the operation hole 11 is also arranged on the side wall of the large-diameter section 12. The tab hole 22 and the fixing hole 23 both penetrate the large-diameter section 12 and form openings on the step surface, facilitating observation and operation. The top plate 14 is fixed to the end of the small-diameter section 13 by screws, which is convenient for disassembly and facilitates inspection and maintenance.

[0046] This embodiment also provides a method for detecting the welding quality of the cylindrical battery tab welding, using the above-mentioned cylindrical battery tab welding quality detection tooling; including the following steps: S1. Before each production of the first piece, prepare the tabs corresponding to three battery cells and prepare the detection tooling in advance. Pass the tabs used during the production of the battery cells through the tab holes 22 and fixing holes 23 on the detection tooling in sequence, and fix the tabs with adhesive tape or the fixing mechanism 3.

[0047] S2. Insert the detection tooling with the tabs installed into the steel shell used during the production of the battery cells, ensuring that the large-diameter section 12 of the detection tooling is completely embedded in the steel shell and fits closely against the inner wall of the steel shell.

[0048] S3. Perform a welding operation through the welding needle holes 21 to perform bottom welding of the tabs to the bottom of the steel shell.

[0049] S4. Remove the detection tooling, apply a pulling force to two of the tabs and break the tabs, and check whether there is any residue of the tabs on the steel shell. If there is residue, it indicates that the welding strength meets the requirements; if there is no residue, the welding parameters need to be adjusted and retested.

[0050] S5. Perform a welding tensile test on the other tab, record the tensile data, and determine whether it meets the standard.

[0051] The implementation principle of this embodiment is as follows: Through a dedicated detection tooling, rapid detection of the tab welding quality is achieved, avoiding potential safety hazards caused by scrapped battery cells. At the same time, by quantifying the welding tensile data, the accuracy and reliability of the detection results are improved. This method is simple to operate, highly efficient, can effectively shorten the downtime, and improve the production efficiency.

[0052] The embodiments of this specific implementation manner are all preferred embodiments of the present invention, and do not limit the protection scope of the present invention accordingly. Therefore, all equivalent changes made according to the structure, shape, and principle of the present invention should be covered within the protection scope of the present invention.

Claims

1. A cylindrical battery tab welding quality inspection tooling, characterized in that It includes a cylindrical shell (1), the diameter of the shell (1) being matched with the inner diameter of the steel shell. One end of the cylindrical shell (1) is open, and the other end is provided with an end plate (2); a welding pin hole (21) is formed in the middle position of the end plate (2), and an ear hole (22) is formed in the edge position. The ear passes through the ear hole (22) from inside the cylindrical shell (1) and extends to the outside of the end plate (2), and the ear covers the welding pin hole (21).

2. The welding quality detection tooling for the tab of a cylindrical battery according to claim 1, characterized in that It further includes a fixing mechanism (3) for fixing the ear; the fixing mechanism (3) includes a fixing frame (31) arranged inside the shell (1) and a first fixing clip (32) arranged on the fixing frame (31); a first through hole (311) is formed in the fixing frame (31) for the ear to pass through, and the first fixing clip (32) thus clamps and fixes the ear.

3. The fixture for detecting the welding quality of the tab of a cylindrical battery according to claim 2, wherein, Fixing holes (23) are further formed in the edge of the end plate (2), and second through holes (312) corresponding to the fixing holes (23) are formed in the fixing frame (31); the fixing mechanism (3) further includes a second fixing clip (33) arranged on the fixing frame (31). The ear passes through the fixing hole (23) and the second through hole (312) from outside the shell (1) and is fixed by the second fixing clip (33).

4. A cylindrical battery tab welding quality detection tooling according to claim 3, characterized in that, The fixing frame (31) is slidably connected to the shell (1), and the fixing frame (31) can move along the length direction of the shell (1).

5. A cylindrical battery tab welding quality detection tooling according to claim 4, characterized in that, Both the first fixing clip (32) and the second fixing clip (33) are provided with operation buttons (34). An operation hole (11) is formed in the side wall of the shell (1), and the operation buttons (34) are arranged at the operation hole (11).

6. A cylindrical battery tab welding quality detection tooling according to claim 5, characterized in that When the operation button (34) is located at the operation hole (11), the operation button (34) extends into the operation hole (11) and makes the first fixing clip (32) and the second fixing clip (33) in a clamped state; when the fixing frame (31) moves in the shell (1), the operation button (34) contracts under the extrusion of the side wall of the shell (1) to make the first fixing clip (32) and the second fixing clip (33) in an open state.

7. The fixture for detecting the welding quality of the tab of a cylindrical battery according to claim 3, characterized in that A first plug (313) inserted and matched with the ear hole (22) and a second plug (314) inserted and matched with the fixing hole (23) are arranged on the fixing frame (31). Both the first plug (313) and the second plug (314) are tubular; the first plug (313) communicates with the first through hole (311), and the second plug (314) communicates with the second through hole (312) for the ear to pass through.

8. A cylindrical battery tab welding quality detection tooling according to claim 3, characterized in that, The shell (1) includes a large-diameter section (12) and a small-diameter section (13). The outer diameter of the large-diameter section (12) is equal to the inner diameter of the steel shell, and the small-diameter section (13) is coaxially arranged with the large-diameter section (12); there is a stepped surface between the large-diameter section (12) and the small-diameter section (13); both the ear hole (22) and the fixing hole (23) penetrate through the large-diameter section (12) and form openings on the stepped surface. The fixing frame (31) is arranged inside the large-diameter section (12).

9. A cylindrical battery tab welding quality detection tooling according to claim 8, characterized in that, One end of the small-diameter section (13) away from the large-diameter section (12) is provided with a top plate (14), and the diameter of the top plate (14) is the same as that of the large-diameter section (12).

10. A method for detecting the welding quality of the tab of a cylindrical battery, characterized in that, Adopt the cylindrical battery tab welding quality detection tooling described in any one of claims 1-9; and include the following steps: Pass the tab used when producing the first-piece battery cell through the detection tooling for fixation, and install it into the steel shell used when producing the battery cell, and directly weld it; Apply a pulling force to the tab and break the tab, check whether there is any residue of the tab on the steel shell. If there is residue, the welding strength meets the requirements. If there is no residue, adjust the welding parameters and retest; at the same time, test the welding pulling force to digitalize the welding pulling force data.

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