An electric cell assembly production line

Abstract

The application provides a battery cell assembling method, by adjusting the placement state of the battery cell, using the diaphragm to cover the bottom and opposite two sides and upper edges of the opposite two sides of the battery cell, after adding the protection sheet, the battery cell is placed into the battery shell one by one by clamping the protection sheet, the existing battery cell assembling method in the background technology is no longer limited to the form characteristics of the battery cell, and the battery cell adhesion process, the shaping process of the combined battery cell, the installation and welding process of the end plate and the side plate are saved. The application also provides a battery cell assembling production line, by setting the film station, the tab welding and cutting station, the protection sheet adding and bending station, the battery cell stacking station and the protection sheet welding station, the foregoing battery cell assembling method is realized. The process method and the production line for realizing the method can save the shaping equipment and the side seam welding equipment, and save the raw material cost of the end plate, the side plate and the partition plate.

Description

Technical Field

[0001] This invention generally relates to the field of lithium battery technology. More specifically, this invention relates to a cell assembly production line. Background Technology

[0002] Lithium-ion batteries are a type of battery that uses lithium metal or lithium alloys as positive / negative electrode materials and a non-aqueous electrolyte solution. They have advantages such as high energy density, long cycle life, and low self-discharge rate. In China, lithium-ion battery technology is mainly used in the new energy vehicle industry and the energy storage industry.

[0003] Existing lithium battery structures typically consist of individual cells placed within a square band formed by end plates and side plates. CN117747960A provides a lithium battery module shape correction device, detailing the assembly process of a lithium battery pack. The specific process involves applying adhesive to the left and right sides of each individual cell before placing them into the square band to roughly fix adjacent cells. A partition is then placed between adjacent cells, and the left and right sides of each cell are sequentially glued together to form a cuboid. A fixture is then used to shape the cuboid. After shaping, the end plates and side plates are installed and welded together, ultimately placing the cell assembly within the square band. A busbar is also installed, and the positive and negative terminals of the cells are welded to the busbar. Before assembling the battery, the entire square band and the cell assembly within it are placed into the battery casing. Finally, the battery casing is sealed to complete the entire cell assembly process.

[0004] The production method of assembling batteries using the above-mentioned cells is relatively complicated, resulting in low production efficiency. In addition, the processes of applying glue and bonding to both sides of the cells, shaping the bonded cell assemblies, and welding the end plates and side plates require a variety of equipment and a large floor space, resulting in high cost and weakening the competitiveness of the products.

[0005] In view of this, how to develop a new cell assembly process, as well as the equipment or production line required to implement the new process, improve the production efficiency of lithium batteries, reduce production costs, and enhance product competitiveness has become an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0006] In order to at least solve one or more of the technical problems in the background art described above, the present invention provides the following solution.

[0007] In a first aspect, the present invention provides a method for assembling battery cells, the technical solution of which is as follows: The cell assembly method includes: S1: Place the battery cell in a flat position; S2: Place the separator at the bottom of a single cell, and make the separator cover the opposite sides of the cell that do not have tabs and the upper edges of the opposite sides; S3: Weld each cluster of tabs of a single cell to ensure that each cluster of tabs is no longer loose; trim each cluster of tabs after welding a single cell to make its edges flush. S4: Connect the protective sheet to each cluster of tabs with flush edges obtained in step S3, and bend the first end of all the protective sheets upward to make them L-shaped; the first end is the end of the protective sheet near each cluster of tabs; the length of the protective sheet added to the same single cell remains the same, and the number of the length types of the protective sheets is the same as the number of cells stacked. S5: Individual cells with protective plates of different lengths are stacked into the battery casing in order of decreasing length of the connected protective plates, from bottom to top. Among the stacked cells, the length of the protective plates connected to each cluster of tabs at the same position of different cells increases sequentially from top to bottom, and the increment in length is the same as the thickness of the individual cell. The same position refers to the position with the same horizontal coordinate in the same space. S6: Weld protective sheets of different lengths to each cluster of tabs at the same position of the stacked different cells; place the ends of the welded protective sheets into the battery casing, and connect the protective sheets at the same position to the corresponding terminals located in the battery casing; S7: Seal the battery casing.

[0008] Preferably, before placing the separator at the bottom of a single battery cell, S2 further includes bending the separator to form a concave structure, so as to facilitate placing the battery cell into the concave structure of the separator, and making the separator cover the opposite sides of the battery cell without tabs and the upper edges of the sides; the separator is made of PP film and has a thickness of 0.5 mm.

[0009] Preferably, before welding each cluster of tabs of a single battery cell, S3 further includes: using pneumatic fingers to hold each cluster of tabs.

[0010] Preferably, step S6 further includes bending the second ends of all the protective sheets again to make the protective sheets into a Z-shaped shape, so as to place the second ends of the welded protective sheets into the battery housing to connect the corresponding terminals located in the battery housing; the second ends are the ends of the protective sheets away from each cluster of tabs.

[0011] Preferably, or, step S4 includes: attaching the protective sheet to each cluster of tabs with flush edges obtained in step S3, and bending the second ends of all the protective sheets downward to form an L-shape, and then bending the first ends of all the protective sheets upward to form a Z-shape; the length of the protective sheets added to the same single cell remains the same, and the number of the length types of the protective sheets is the same as the number of stacked cells; the first end is the end of the protective sheet near each cluster of tabs, and the second end is the end of the protective sheet away from each cluster of tabs.

[0012] Preferably, a horizontal slit is provided so that the protective sheet passes through one side of the slit to the other side, and a roller is used on the other side of the slit to press the protective sheet upward or downward to bend the protective sheet.

[0013] Preferably, in step S4, connecting the protective sheet to each cluster of tabs with flush edges obtained in step S3 includes: connecting each cluster of tabs located at the negative electrode of the battery cell to the protective sheet by ultrasonic welding, and connecting each cluster of tabs located at the positive electrode of the battery cell to the protective sheet by riveting.

[0014] Preferably, before the ultrasonic welding process, the two protective plates to be connected can be placed on the upper and lower sides of any tab on the negative electrode of the battery cell, respectively, for welding; before the riveting process, the two protective plates to be connected can be placed on the upper and lower sides of any tab on the positive electrode of the battery cell, and holes can be drilled to penetrate the two protective plates and the tab.

[0015] Preferably, in step S5, stacking a single cell into the battery housing includes: folding the separator covering the upper edges of the opposite sides of the cell without tabs by 90 degrees; clamping and lifting the folded separator to transfer the single cell with the bottom and side films to the battery housing and placing it into the battery housing.

[0016] Preferably, step S7 includes placing a hot melt plate between the top cover and the battery housing, so that the top cover and the battery housing contact the hot melt plate to heat the top cover and the battery housing respectively; removing the hot melt plate, so that the top cover and the battery housing are brought close together and pressed together to seal the battery housing with the top cover.

[0017] In the second aspect, an assembly line for implementing the cell assembly method provided in the first aspect of the present invention is also provided, the technical solution of which is as follows: The battery cell assembly production line includes the following components arranged sequentially: The membrane supply station is used to place the membrane at the bottom of a single battery cell after adjusting the battery cell to place it in a flat position, and to cover the opposite sides of the battery cell that do not have tabs and the upper edges of said sides. The tab welding station is used to weld each cluster of tabs for a single battery cell so that each cluster of tabs is no longer loose. The tab cutting station is used to cut each cluster of tabs after individual cells are welded, so that the edges of each cluster of tabs are flush. The protective sheet installation station is used to connect the protective sheet to each cluster of tabs after cutting; the length of the protective sheet installed on the same single cell remains the same, and the number of the length types of the protective sheet is the same as the number of cells stacked. The protective sheet bending station is used to bend the second end of the protective sheet connected to each cluster of electrodes downward to make the protective sheet into an L-shaped shape, and then bend the first end of the protective sheet upward to make the protective sheet finally into a Z-shaped shape; the first end is the end of the protective sheet close to each cluster of electrodes, and the second end is the end of the protective sheet away from each cluster of electrodes; The cell stacking station is used to stack individual cells with protective plates of different lengths into the battery casing in descending order of the length of the protective plates connected to each cluster of cut tabs. In the stacked cells, the length of the protective plates connected to each cluster of tabs at the same position on different cells increases sequentially from top to bottom, with the increase in length being the same as the thickness of the individual cell. The "same position" refers to a position with the same horizontal coordinate within the same space. The protective sheet welding station is used to weld protective sheets of different lengths to the same positions of stacked different cells and to each cluster of tabs. The packaging station is used to allow the welded protective sheet to enter the battery housing, connect the protective sheet at the same position to the corresponding terminal in the battery housing, and seal the battery housing.

[0018] Preferably, between the packaging station and the protective sheet welding station, a resistance testing station is further included. The resistance testing station is used to test the resistance value of the battery after the individual cells are assembled into a battery.

[0019] Preferably, the membrane supply station includes a horizontal forming plate and U-shaped molds respectively disposed on both sides of the horizontal forming plate. The thickness of the inner groove of the U-shaped mold is slightly less than the thickness of the horizontal forming plate, so that when the diaphragm is placed on the upper surface and both sides of the horizontal forming plate, the U-shaped mold moves toward the horizontal forming plate to squeeze the diaphragm into the gap between the horizontal forming plate and the U-shaped mold, and forms a concave structure for covering the opposite sides of the battery cell that do not have tabs and the upper edge of the opposite sides.

[0020] Preferably, the tab welding station includes a finger cylinder for clamping each cluster of tabs of the battery cell before tab welding.

[0021] Preferably, the protective sheet installation station includes a first installation module and a second installation module. The first installation module is used to place the two protective sheets to be connected on the upper and lower sides of any tab on the negative electrode of the battery cell, so as to weld the protective sheets to the tab. The second installation module is used to place the two protective sheets to be connected on the upper and lower sides of any tab on the positive electrode of the battery cell, and drill holes to penetrate the two protective sheets and the tab, so as to rivet the protective sheets to the tab.

[0022] Preferably, the first installation module includes two robotic arms with suction cups, used to adsorb protective sheets and place them on the upper and lower sides of the same tab of the negative electrode of the battery cell, respectively, for welding the protective sheets to the tabs; the second installation module includes a first suction cup and a second suction cup symmetrically arranged for adsorbing the protective sheets, the first suction cup and the second suction cup are respectively fixedly connected to a half-tooth gear, the two half-tooth gears are located on opposite sides of the same rack and respectively mesh with the rack, the two half-tooth gears are respectively hinged to a fixed base, the rack is fixedly connected to a lead screw nut, the lead screw nut is slidably arranged relative to the fixed base along the axial direction of the lead screw, and with The lead screw connected to the lead screw nut is used to drive the lead screw nut to move along the axial direction of the lead screw when rotating, so that when the rack drives the two half-tooth gears to rotate around the hinge with the fixed base, the first suction cup and the second suction cup move closer or further apart; the fixed base is also connected to the output end of the rotary motor, which is mounted on the three-axis module. When the first suction cup and the second suction cup move closer together so that their adsorption surfaces are parallel to each other, the three-axis module is used to adjust the relative position of the first suction cup and / or the second suction cup with the positive electrode tab of the battery cell; both the first mounting module and the second mounting module are provided with a protective sheet storage area.

[0023] Preferably, the protective sheet bending station includes a liner for bending, the liner having a slit for the protective sheet to pass through from one side of the liner to the other side, and the other side of the liner being provided with a roller that can conform to the liner and move upward or downward to crush and bend the protective sheet passing through the slit.

[0024] Preferably, the cell stacking station includes two flipping suction cups, which are used to adsorb a first folding film and a second folding film, respectively. The first folding film and the second folding film are diaphragms that cover the upper edges of opposite sides of the cell that do not have tabs. The flipping suction cups have a notch in the middle, and a clamping part is provided above the notch that can be raised and lowered. The clamping part is used to clamp the first folding film and the second folding film to lift or lower the cell whose opposite sides and bottom are covered and to transfer the cell.

[0025] Preferably, it further includes an anti-detachment device located between the two flipping suction cups to prevent the battery cell from falling off. The anti-detachment device includes multiple sets of symmetrically arranged L-shaped hooks, each L-shaped hook being connected to a drive device to adjust the distance between any two symmetrically arranged L-shaped hooks in any set. The drive device is fixedly connected to an adjustment plate, which is adjustable in height relative to the clamping part.

[0026] Preferably, the packaging station includes a hot-melt device, which includes a tray for placing the battery casing and a pressure plate that can be raised and lowered above the tray. The lower surface of the pressure plate is used to adsorb the battery casing and its top cover. When the tray is in a preset position, the pressure plate is located directly above the tray. The station also includes a horizontally extendable hot-melt plate, which is used to be positioned between the tray and the pressure plate. When the tray is in the preset position, the pressure plate adsorbs the battery casing and its top cover and moves downward to jointly squeeze the top cover, the hot-melt plate, and the battery casing, so that the top cover and the battery casing come into contact with the hot-melt plate.

[0027] The technical solution provided in this application may include the following beneficial effects: The method of this invention adjusts the placement of the battery cells, using a separator to cover the bottom, opposite sides, and upper edges of the cells. After adding protective sheets, the cells are individually placed into the battery casing by clamping the protective sheets. This eliminates the need for existing cell assembly methods due to the shape characteristics of the cells, thus saving the cell bonding process, the post-assembly cell shaping process, the installation of end plates and side plates, and the welding process. The production line of this invention implements the aforementioned method by setting up a separator supply station, a tab welding and cutting station, a protective sheet addition and bending station, a cell stacking station, and a protective sheet welding station.

[0028] Compared with the prior art and existing assembly processes, without changing the original electrode tab welding process and the positive and negative electrode connection process, the process method of the present invention and the production line that implements the method can save shaping equipment and side seam welding equipment, as well as the raw material costs of end plates, side plates and partitions. Attached Figure Description

[0029] The above and other objects, features, and advantages of exemplary embodiments of the present invention will become readily apparent from the following detailed description taken in conjunction with the accompanying drawings. In the drawings, several embodiments of the invention are illustrated by way of example and not limitation, and like or corresponding reference numerals denote like or corresponding parts wherein: Figure 1 This is a first top perspective view of the battery cell assembly production line of the present invention; Figure 2This is a second top perspective view of the battery cell assembly production line of the present invention; Figure 3 This is a third top perspective view of the battery cell assembly production line of the present invention; Figure 4 It is shown Figure 2 Enlarged view of a portion at point A; Figure 5 It is shown Figure 2 A magnified view of section B; Figure 6 It is shown Figure 2 A magnified view of a portion at point C; Figure 7 It is shown Figure 3 A magnified view of a portion at point D; Figure 8 It is shown Figure 3 A magnified view of a portion at point E; Figure 9 This is a schematic diagram showing the assembly status of the protective sheet; Explanation of reference numerals in the attached figures: 11. Battery cell; 12. Separator; 13. Tab; 14. Protective sheet; 15. Battery casing; 16. Top cover; 31. Horizontal forming plate; 32. U-shaped mold; 61. First suction cup; 62. Second suction cup; 63. Fixing base; 71. Liner plate; 72. Roller; 81. Tilting suction cup; 82. Notch; 83. Clamping part; 91. Anti-detachment device; 92. Adjusting plate; 101. Tray; 102. Pressure plate; 103. Hot melt plate; 100. Film supply station; 200. Tab welding station; 300. Tab cutting station; 400. Protective sheet installation station; 500. Protective sheet bending station; 600. Battery cell stacking station; 700. Protective sheet welding station; 800. Packaging station. Detailed Implementation

[0030] Embodiments will now be described with reference to the accompanying drawings. It should be understood that, for the sake of simplicity and clarity, reference numerals may be repeated in the drawings to indicate corresponding or similar elements where deemed appropriate. Furthermore, numerous specific details are set forth in this invention to provide a thorough understanding of the embodiments described herein. However, those skilled in the art will understand that the embodiments described herein can be practiced without these specific details. In other instances, well-known methods, processes, and components have not been described in detail so as not to obscure the embodiments described herein. Moreover, this description should not be construed as limiting the scope of the embodiments described herein.

[0031] According to an embodiment of the present invention, a cell assembly method is provided, comprising: S1: Place the battery cell 11 in a flat position; S2: Place the diaphragm 12 at the bottom of the individual cell 11, and make the diaphragm 12 cover the opposite sides of the cell 11 without tabs 13 and the upper edge of the opposite sides. S3: Solder each cluster of tabs 13 of a single cell 11 to make each cluster of tabs 13 no longer loose; trim each cluster of tabs 13 of a single cell 11 after soldering to make its edges flush. S4: Connect the protective sheet 14 to each cluster of tabs 13 with flush edges obtained in step S3, and bend the first end of all the protective sheets 14 upward to make them L-shaped; the first end is the end of the protective sheet 14 near each cluster of tabs 13; the length of the protective sheet 14 added to the same single cell 11 is kept the same, and the number of length types of the protective sheet 14 is the same as the number of stacked cells 11; S5: Individual cells 11 connected to protection plates 14 of different lengths are stacked into the battery casing 15 from bottom to top in order of decreasing length of the connected protection plates 14; among the stacked cells 11, the length of the protection plates 14 connected to each cluster of tabs 13 at the same position of different cells 11 increases sequentially from top to bottom, and the increasing length value is the same as the thickness value of the individual cells 11; the same position refers to the position with the same horizontal coordinate in the same space; S6: Weld protective sheets 14 of different lengths to the same position of stacked different cells 11 and to each cluster of tabs 13; place the end of the welded protective sheet 14 into the battery housing 15, and connect the protective sheet 14 at the same position to the corresponding terminal located in the battery housing 15. S7: Sealed battery casing 15.

[0032] In step S2 mentioned above, before placing the separator 12 at the bottom of the individual battery cell 11, the separator 12 can be bent to make the separator 12 concave, so that the battery cell 11 can be placed into the concave structure of the separator 12, and the separator 12 covers the opposite sides of the battery cell 11 without the tabs 13 and the upper edges of the sides; the separator 12 is made of PP film and has a thickness of 0.5mm.

[0033] In step S3 mentioned earlier, before soldering each cluster of tabs 13 of a single battery cell 11, each cluster of tabs 13 can be held using pneumatic fingers. The advantage of using pneumatic fingers to hold the tabs 13 is that it improves the soldering quality of the tabs 13 and prevents incomplete soldering or cold solder joints. The tabs 13 can be cut using a guillotine.

[0034] In step S6 mentioned above, the second ends of all protective sheets 14 can be bent again to form a Z-shape, facilitating the insertion of the welded second ends of the protective sheets 14 into the battery housing 15 to connect with the corresponding terminals located within the battery housing 15. The second end is the end of the protective sheet 14 furthest from each cluster of tabs 13. The reason for bending the protective sheets 14 into a Z-shape in this step is that if the protective sheets 14 are only bent into an L-shape, the second end of the protective sheets 14 would need to be manually bent again to allow them to enter the battery housing 15. Since the protective sheets 14 have only been bent once into an L-shape, there would be no reference point for manually bending the second end again when inserting them into the battery housing 15, leading to greater arbitrariness and affecting product consistency, thus compromising quality. Therefore, bending the second end of the protective sheets 14 into a Z-shape provides a bending reference for the re-bending when inserting the protective sheets 14 into the battery housing 15, improving production process control and product consistency.

[0035] Alternatively, the protective sheet 14 can be bent twice, that is, bent at its first and second ends. In step S4, the protective sheet 14 can first be connected to each cluster of tabs 13 with flush edges obtained in step S3, and the second ends of all the protective sheets 14 can be bent downwards to form an L-shape. Then, the first ends of all the protective sheets 14 can be bent upwards to form a Z-shape. The length of the protective sheets 14 added to the same single cell 11 remains the same, and the number of length types of the protective sheets 14 is the same as the number of stacked cells 11. The first end is the end of the protective sheet 14 closest to each cluster of tabs 13, and the second end is the end of the protective sheet 14 furthest from each cluster of tabs 13. Obviously, using a bending machine to complete the two bending of the protective sheet 14 at one station, the bending of the second end of the protective sheet 14 is convenient for use when the protective sheet 14 enters the battery casing 15. The bending process is completed in advance, so one less bending machine can be set up at the subsequent station, saving costs.

[0036] Here, the length of the protective plates 14 attached to the same single battery cell 11 remains the same, and the number of different length types of the protective plates 14 is the same as the number of stacked battery cells 11. This means that the length of the protective plates 14 attached to each tab 13 of a battery cell 11 is the same. In this way, after the battery cells 11 are stacked in step S5, the height of the protective plates 14 connected to the tabs 13 of each battery cell 11 is the same. Since the protective plates 14 at the same position of all the stacked battery cells 11 need to be soldered in step S6, the length of the protective plates 14 at the same position of different battery cells 11 connected to each cluster of tabs 13 increases sequentially from top to bottom, and the increase in length is the same as the thickness of a single battery cell 11. This ensures that after all the battery cells 11 are stacked, the height of all the protective plates 14 at the same position is approximately the same, so that each protective plate 14 can contact each other sequentially and facilitate soldering.

[0037] In the above embodiments, in order to bend the first end and / or the second end of the protective sheet 14, a horizontal slit can be provided so that the protective sheet 14 passes through one side of the slit to the other side. On the other side of the slit, a roller 72 is used to press the protective sheet 14 upward or downward to bend the protective sheet 14.

[0038] In one embodiment, in step S4, the protective sheet 14 is connected to each cluster of tabs 13 with flush edges obtained in step S3. Each cluster of tabs 13 located at the negative electrode of the cell 11 can be connected to the protective sheet 14 by ultrasonic welding, and each cluster of tabs 13 located at the positive electrode of the cell 11 can be connected to the protective sheet 14 by riveting.

[0039] The negative electrode protection sheet is made of copper and stainless steel, and the negative electrode is connected by ultrasonic welding; while the positive electrode protection sheet is made of aluminum and stainless steel, and the positive electrode is connected by drilling and riveting. The reason is that the melting points of the positive and negative electrode materials are different, resulting in different connection methods between the positive and negative electrodes and the protection sheet 14.

[0040] Specifically, before the ultrasonic welding process, the two protective plates 14 to be connected can be placed on either side of the tab 13 at any point on the negative electrode of the battery cell 11, above and below, respectively, for welding. For example, two robotic arms with suction cups can be used in cooperation. The first suction cup places the protective plate 14 on the second suction cup, so that the second suction cup is positioned directly below any point on the negative electrode tab 13. The first suction cup then picks up another protective plate 14 and positions it directly above the tab 13 at that point on the negative electrode. Finally, the protective plate 14 is connected to the tab 13 by ultrasonic welding.

[0041] Before the riveting process, the two protective plates 14 to be connected are placed directly above and below the tabs 13 at either point on the positive terminal of the battery cell 11. Holes are drilled to penetrate the two protective plates 14 and the tabs 13 for riveting. The protective plates 14 at the positive terminal of the battery cell 11 can also be provided by two robotic arms with suction cups working together, as described above; or by other methods, such as those described later in the battery cell assembly production line section.

[0042] In step S5 mentioned above, the individual battery cells 11 are stacked into the battery casing 15. Specifically, the separator 12 covering the upper edges of the opposite sides of the battery cell 11 (excluding the tabs 13) can be folded 90 degrees. The folded separator 12 is then clamped and lifted to transfer the individual battery cells 11, with the bottom and sides covered by the separator, to the battery casing 15 and placed inside it. Obviously, the transfer process does not involve contact with the individual battery cells 11, eliminating the risk of damage to the individual battery cells 11.

[0043] In step S7 mentioned above, a hot-melt plate 103 can be used to heat-melt the top cover 16 and the battery casing 15 separately and then bring them into contact to seal them. For example, the hot-melt plate 103 can be placed between the top cover 16 and the battery casing 15, so that the top cover 16 and the battery casing 15 contact the hot-melt plate 103 so that the hot-melt plate 103 heats the top cover 16 and the battery casing 15 respectively; the hot-melt plate 103 can be removed so that the top cover 16 and the battery casing 15 are brought close to each other and pressed together to seal the battery casing 15 with the top cover 16.

[0044] It is easy to understand that after the cells 11 are stacked into the battery casing 15 in step S5 above, the presence of the separator 12 provides a physical isolation effect between the cells 11. The separator between the cells 11 can form a heat insulation layer between the stacked cells 11, which helps to prevent the thermal runaway of a certain cell 11 from spreading from the runaway cell 11 to other cells 11 around it, thus reducing the risk of damage to the battery pack.

[0045] To implement the cell assembly method of the present invention, the present invention also provides a cell assembly production line, such as... Figures 1 to 8 As shown, it includes the following settings in sequence: The membrane supply station 100 is used to place the membrane 12 at the bottom of a single cell 11 after adjusting the cell 11 so that the cell 11 is placed in a flat position, and to cover the opposite sides of the cell 11 that do not have tabs 13 and the upper edges of the sides. The tab welding station 200 is used to weld each cluster of tabs 13 of a single cell 11 so that each cluster of tabs 13 is no longer loose. The tab cutting station 300 is used to cut each cluster of tabs 13 after the individual battery cell is welded, so that the edges of each cluster of tabs 13 are flush. The protective sheet installation station 400 is used to connect the protective sheet 14 to each cluster of tabs 13 after cutting; the length of the protective sheet 14 installed on the same single cell 11 is kept the same, and the number of the length types of the protective sheet 14 is the same as the number of stacked cells 11. The protective sheet bending station 500 is used to bend the second end of the protective sheet 14 connected to each cluster of tabs 13 after cutting downward to make the protective sheet 14 into an L-shaped shape, and then bend the first end of the protective sheet 14 upward to make the protective sheet 14 finally into a Z-shaped shape; the first end is the end of the protective sheet 14 close to each cluster of tabs 13, and the second end is the end of the protective sheet 14 away from each cluster of tabs 13; The cell stacking station 600 is used to stack individual cells 11 with protective plates 14 of different lengths in the battery housing 15 from bottom to top, according to the order of the length of the protective plates 14 connected to each cluster of tabs 13 after cutting, from longest to shortest. In the stacked cells 11, the length of the protective plates 14 connected to each cluster of tabs 13 at the same position of different cells 11 increases sequentially from top to bottom, and the increase in length is the same as the thickness of the individual cell 11. The same position refers to the position with the same horizontal coordinate in the same space. The protective sheet welding station 700 is used to weld protective sheets 14 of different lengths that are connected to each cluster of tabs 13 at the same position of the stacked different cells 11. The encapsulation station 800 is used to allow the welded protective sheet 14 to enter the battery housing 15, connect the protective sheet 14 at the same position to the corresponding terminal in the battery housing 15, and seal the battery housing 15.

[0046] The protection plate installation station 400 mentioned above is used to extend the length of the tab 13, so that all the positive and negative terminals of the battery cell 11 can be connected separately.

[0047] In the battery cell assembly line section, the protective sheet bending station 500 mentioned above is where the first and second ends of the protective sheet 14 are bent, that is, the protective sheet 14 is bent twice to make it into a Z-shaped form.

[0048] In one embodiment, a resistance testing station is included between the packaging station 800 and the protective sheet welding station 700. This resistance testing station is used to test the resistance value of the battery after the individual cells 11 are assembled into a battery. To meet actual production needs, setting up a resistance testing station can effectively avoid rework caused by the failure to detect defective products after packaging.

[0049] In one embodiment, the membrane supply station 100 includes a horizontal forming plate 31 and U-shaped molds 32 respectively disposed on both sides of the horizontal forming plate 31. The thickness of the inner groove of the U-shaped mold 32 is slightly less than the thickness of the horizontal forming plate 31, so that when the diaphragm 12 is placed on the upper surface and both sides of the horizontal forming plate 31, the U-shaped mold 32 moves toward the horizontal forming plate 31 to squeeze the diaphragm 12 into the gap between the horizontal forming plate 31 and the U-shaped mold 32, forming a concave structure for covering the opposite sides and the upper edges of the opposite sides of the battery cell 11 that do not have tabs 13. This achieves the objective of step S2.

[0050] In another embodiment, the tab welding station 200 includes a finger cylinder for clamping each cluster of tabs 13 of the battery cell 11 before tab welding.

[0051] In one embodiment, the protective sheet installation station 400 may include a first installation module and a second installation module. The first installation module is used to place the two protective sheets 14 to be connected on the upper and lower sides of any tab 13 on the negative electrode of the battery cell 11, so as to weld the protective sheet 14 to the tab 13. The second installation module is used to place the two protective sheets 14 to be connected on the upper and lower sides of any tab 13 on the positive electrode of the battery cell 11, and drill holes to penetrate the two protective sheets 14 and the tab 13, so as to rivet the protective sheet 14 to the tab 13.

[0052] In the above embodiment, the first installation module includes two robotic arms with suction cups, which are used to adsorb the protective sheet 14 and place the adsorbed protective sheet 14 on the upper and lower sides of the same tab 13 of the negative electrode of the battery cell 11, respectively, for welding the protective sheet 14 to the tab 13; the second installation module includes a first suction cup 61 and a second suction cup 62 symmetrically arranged for adsorbing the protective sheet 14. The first suction cup 61 and the second suction cup 62 are respectively fixedly connected to half-tooth gears. The two half-tooth gears are located on opposite sides of the same rack and mesh with the rack respectively. The two half-tooth gears are respectively hinged to the fixed base 63. The rack is fixedly connected to the lead screw nut. The lead screw nut is relative to the fixed base 63 along the axis of the lead screw. The screw, connected to the lead screw nut, is slidably mounted in the axial direction. When rotated, it drives the lead screw nut to move axially along the lead screw, so that when the rack drives the two half-tooth gears to rotate around the hinge point with the fixed base 63, the first suction cup 61 and the second suction cup 62 move closer or further apart. The fixed base 63 is also connected to the output end of a rotary motor, which is mounted on a three-axis module. When the first suction cup 61 and the second suction cup 62 move closer together so that their adsorption surfaces are parallel, the three-axis module is used to adjust the relative position of the first suction cup 61 and / or the second suction cup 62 with the positive electrode tab 13 of the battery cell 11. Both the first and second mounting modules have a protective sheet storage area. The protective sheet storage area is used to store protective sheets of different lengths. As mentioned earlier, the lengths of the protective sheets 14 are the same as the number of stacked battery cells 11.

[0053] The protective sheet bending station 500 mentioned above may include a liner 71 for bending. The liner 71 has a slit for the protective sheet 14 to pass through from one side of the liner 71 to the other side. The other side of the liner 71 is provided with a roller 72 that can conform to the liner 71 and move up or down to crush and bend the protective sheet 14 passing through the slit.

[0054] The liner 71 may include an upper liner and a lower liner. The upper and lower liners are brought close to each other to form the gap mentioned above. This structure also makes it easier for the gap and the protective sheet 14 to be aligned, making it easier for the protective sheet 14 to pass through the gap.

[0055] The above structure can achieve the purpose of step S4.

[0056] In one embodiment, the cell stacking station 600 mentioned above may include two flipping suction cups 81, which are used to adsorb a first folding film and a second folding film, respectively. The first folding film and the second folding film are diaphragms 12 that cover the upper edges of opposite sides of the cell 11 that do not have tabs 13. The flipping suction cup 81 has a notch 82 in the middle, and a clamping part 83 is provided above the notch 82 that can be raised and lowered. The clamping part 83 is used to clamp the first folding film and the second folding film to raise or lower the cell 11 covered on opposite sides and bottom and to transfer the cell 11.

[0057] In the above embodiment, an anti-detachment device 91 is also included, located between the two flipping suction cups 81, to prevent the battery cell 11 from falling off. The anti-detachment device 91 includes multiple sets of symmetrically arranged L-shaped hooks, each L-shaped hook being connected to a drive device to adjust the distance between any two symmetrically arranged L-shaped hooks in any set. The drive device is fixedly connected to an adjusting plate 92, which is vertically adjustable relative to the clamping part 83. The drive device here can be a cylinder, specifically configured such that each L-shaped hook is fixedly connected to the movable end of a cylinder, and the fixed end of the cylinder is located on the adjusting plate 92. By controlling the synchronous action of the two cylinders, the distance between the symmetrically arranged L-shaped hooks is controlled.

[0058] The above structure can achieve the purpose of step S5.

[0059] A fixture can be used at the 700 welding station for the protective sheet. The fixture is used to hold the protective sheet 14 before welding to prevent the individual protective sheets from becoming loose and causing incomplete welding or missing welding.

[0060] In one embodiment, the packaging station 800 includes a hot-melt device, which includes a tray 101 for placing a battery housing 15 and a pressure plate 102 that is vertically and vertically disposed above the tray 101. The lower surface of the pressure plate 102 is used to adsorb the top cover 16 of the battery housing 15. When the tray 101 is in a preset position, the pressure plate 102 is located directly above the tray 101. The device also includes a horizontally telescopic hot-melt plate 103, which is positioned between the tray 101 and the pressure plate 102. When the tray 101 is in the preset position, the pressure plate 102 adsorbs the battery housing 15 and moves its top cover 16 downward to jointly squeeze the top cover 16, the hot-melt plate 103, and the battery housing 15, so that the top cover 16 and the battery housing 15 come into contact with the hot-melt plate 103.

[0061] This structure is used to achieve the purpose of step S7.

[0062] In the above embodiments, the hot melt plate 103 can be made of Teflon-plated copper plate, and its horizontal extension and retraction can be controlled by a cylinder.

[0063] It should be understood that the possible terms "first" or "second," etc., in the claims, specification, and drawings disclosed in this invention are used to distinguish different objects, rather than to describe a specific order. The terms "comprising" and "including" used in the specification and claims of this invention indicate the presence of the described features, integrals, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or collections thereof.

[0064] It should also be understood that the terminology used in this disclosure is for the purpose of describing particular embodiments only and is not intended to limit the scope of the disclosure. As used in this disclosure and claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used in this disclosure and claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes such combinations.

[0065] While the embodiments of the present invention are described above, these are merely examples for the purpose of facilitating understanding of the invention and are not intended to limit the scope or application scenarios of the invention. Any person skilled in the art can make any modifications and changes in form and detail of the implementation without departing from the spirit and scope disclosed herein; however, the patent protection scope of the present invention shall still be determined by the scope defined in the appended claims.

Claims

1. A battery cell assembly production line, characterized in that, Including the following settings in sequence: A membrane supply station (100) is used to place a membrane (12) at the bottom of a single cell (11) after adjusting the cell (11) to place the cell (11) in a flat position, and to cover the opposite sides of the cell (11) without tabs (13) and the upper edges of said sides. A tab welding station (200) is used to weld each cluster of tabs (13) of a single cell (11) so that each cluster of tabs (13) is no longer loose; The tab cutting station (300) is used to cut each cluster of tabs (13) after the individual battery cell is welded, so that the edges of each cluster of tabs (13) are flush; The protective sheet installation station (400) is used to connect the protective sheet (14) to each cluster of tabs (13) after cutting; the length of the protective sheet (14) installed on the same single cell (11) is kept the same, and the number of the length types of the protective sheet (14) is the same as the number of stacked cells (11); The protective sheet bending station (500) is used to bend the second end of the protective sheet (14) connected to each cluster of tabs (13) after cutting downwards to make the protective sheet (14) into an L-shape, and then bend the first end of the protective sheet (14) upwards to make the protective sheet (14) finally into a Z-shape; the first end is the end of the protective sheet (14) close to each cluster of tabs (13), and the second end is the end of the protective sheet (14) away from each cluster of tabs (13); The cell stacking station (600) is used to stack individual cells (11) with protective plates (14) of different lengths into the battery casing (15) in order of decreasing length of the protective plates (14) connected to each cluster of tabs (13) after cutting. Among the stacked cells (11), the length of the protective plates (14) connected to each cluster of tabs (13) at the same position of different cells (11) increases sequentially from top to bottom, and the increasing length value is the same as the thickness value of the individual cell (11). The same position refers to the position with the same horizontal coordinate in the same space. The protective sheet welding station (700) is used to weld the protective sheets (14) of different lengths that are connected to each cluster of tabs (13) at the same position of the stacked different cells (11). The packaging station (800) is used to allow the welded protective sheet (14) to enter the battery housing (15), and to connect the protective sheet (14) at the same position to the corresponding terminal in the battery housing (15), and to seal the battery housing (15).

2. The battery cell assembly production line according to claim 1, characterized in that, Between the packaging station and the protective sheet welding station, there is also a resistance testing station, which is used to test the resistance value of the battery after the individual cells (11) are assembled into a battery.

3. The battery cell assembly production line according to claim 1, characterized in that, The film supply station includes a horizontal forming plate (31) and U-shaped molds (32) respectively disposed on both sides of the horizontal forming plate (31). The thickness of the inner groove of the U-shaped mold (32) is slightly less than the thickness of the horizontal forming plate (31). When the diaphragm (12) is placed on the upper surface and both sides of the horizontal forming plate (31), the U-shaped mold (32) moves toward the horizontal forming plate (31) to squeeze the diaphragm (12) into the gap between the horizontal forming plate (31) and the U-shaped mold (32), and forms a concave structure for covering the opposite sides of the battery cell (11) without tabs and the upper edge of the opposite sides.

4. The cell assembly production line according to claim 1, characterized in that, The electrode welding station includes a finger cylinder for holding each cluster of electrodes (13) of the battery cell (11) before electrode welding.

5. A cell assembly production line according to claim 1, characterized in that, The protective sheet installation station includes a first installation module and a second installation module. The first installation module is used to place the two protective sheets (14) to be connected on the upper and lower sides of any tab (13) on the negative electrode of the cell (11) respectively, so as to weld the protective sheet (14) to the tab (13). The second installation module is used to place the two protective sheets (14) to be connected on the upper and lower sides of any tab (13) on the positive electrode of the cell (11) respectively, and drill holes to penetrate the two protective sheets (14) and the tab (13) so as to rivet the protective sheet (14) to the tab (13).

6. A cell assembly production line according to claim 5, characterized in that, The first installation module includes two robotic arms with suction cups, which are used to adsorb the protective sheet (14) and place the adsorbed protective sheet (14) on the upper and lower sides of the same tab (13) of the negative electrode of the cell (11) respectively, so as to weld the protective sheet (14) to the tab (13); the second installation module includes a first suction cup (61) and a second suction cup (62) symmetrically arranged for adsorbing the protective sheet (14). The first suction cup (61) and the second suction cup (62) are respectively fixedly connected to half-tooth gears. The two half-tooth gears are located on opposite sides of the same rack and mesh with the rack respectively. The two half-tooth gears are respectively hinged to the fixed base (63). The rack is fixedly connected to the lead screw nut. The lead screw nut slides relative to the fixed base (63) along the axial direction of the lead screw. The screw connected to the lead screw nut is configured to drive the lead screw nut to move along the axial direction of the lead screw when rotating, so that when the rack drives the two half-tooth gears to rotate around the hinge with the fixed seat (63), the first suction cup (61) and the second suction cup (62) move closer or further away from each other; the fixed seat (63) is also connected to the output end of the rotary motor, which is mounted on the three-axis module. When the first suction cup (61) and the second suction cup (62) move closer to each other so that their adsorption surfaces are parallel to each other, the three-axis module is used to adjust the relative position of the first suction cup (61) and / or the second suction cup (62) with the positive electrode tab (13) of the battery cell (11); both the first mounting module and the second mounting module are provided with a protective sheet storage area.

7. A cell assembly production line according to claim 1, characterized in that, The protective sheet bending station includes a liner (71) for bending, the liner (71) having a slit for the protective sheet (14) to pass through from one side of the liner (71) to the other side, and the other side of the liner (71) is provided with a roller (72) that can conform to the liner (71) and move up or down to crush and bend the protective sheet (14) passing through the slit.

8. A cell assembly production line according to claim 1, characterized in that, The cell stacking station includes two flipping suction cups (81), which are used to adsorb the first folding film and the second folding film respectively. The first folding film and the second folding film are diaphragms that cover the upper edges of the opposite sides of the cell without tabs (13). The flipping suction cup (81) has a notch (82) in the middle. A clamping part (83) can be raised and lowered directly above the notch (82). The clamping part (83) is used to clamp the first folding film and the second folding film to lift or lower the cell (11) covered on the opposite sides and bottom and to transfer the cell (11).

9. A cell assembly production line according to claim 8, characterized in that, It also includes an anti-detachment device (91) located between the two flipping suction cups (81) to prevent the battery cell (11) from falling off. The anti-detachment device (91) includes multiple sets of L-shaped hooks arranged symmetrically. Each L-shaped hook is connected to a drive device to adjust the distance between any two L-shaped hooks arranged symmetrically. The drive device is fixedly connected to an adjustment plate (92), which is adjustable relative to the clamping part (83).

10. A battery cell assembly production line according to claim 1, characterized in that, The packaging station includes a hot-melt device, which includes a tray (101) for placing the battery casing (15) and a pressure plate (102) that can be raised and lowered above the tray (101). The lower surface of the pressure plate (102) is used to adsorb the top cover (16) of the battery casing (15). When the tray (101) is in a preset position, the pressure plate (102) is located directly above the tray (101). It also includes a horizontally extendable hot-melt plate (103), which is used to be placed between the tray (101) and the pressure plate (102). When the tray (101) is in the preset position, the pressure plate (102) adsorbs the top cover (16) of the battery casing (15) and moves downward to jointly squeeze the top cover (16), the hot-melt plate (103), and the battery casing (15) so that the top cover (16) and the battery casing (15) come into contact with the hot-melt plate (103).

Images