Welding method and welding apparatus

Abstract

This invention provides a welding method and welding equipment. The welding method includes: heating an electrode tab to a predetermined temperature range to soften the non-conductive layer; bidirectionally extruding and shaping the heated electrode tab in its thickness direction, thereby extruding a portion of the non-conductive layer within the electrode tab to reduce its thickness; placing a foil on the surface of at least one conductive layer; detecting the thickness of the non-conductive layer of the extruded electrode tab; if the thickness of the non-conductive layer is within a predetermined range, performing ultrasonic welding; if the thickness of the non-conductive layer is outside the predetermined range, marking it and directly recycling it. This invention reduces the thickness of the non-metallic layer within the electrode tab by extrusion before welding, thereby increasing the effective welding area of ​​the foil and metallic layer. Subsequent welding requires less pressure and fewer parameters, increasing the welding head life and reducing material adhesion during the welding process.

Description

Technical Field

[0001] This invention relates to the field of ultrasonic welding technology, and more particularly to a welding method and welding equipment. Background Technology

[0002] Ultrasonic welding utilizes high-frequency vibration waves transmitted to the surfaces of two objects to be welded. Under pressure, the surfaces of the two objects rub against each other, forming a fusion between molecular layers.

[0003] Traditional ultrasonic welding of metals and non-metals utilizes a toothed mechanism design to rapidly melt and extrude the non-metallic region into the toothless area, completing the metal-to-non-metal weld. Due to the non-conductivity of non-metals, the primary electron conduction capability is achieved through the weld tooth area. For these reasons, traditional ultrasonic welding requires sufficient containment space to accommodate and weld the extruded non-metallic layer during the welding process. Furthermore, welding between metal layers and between metal and non-metal layers places high demands on the equipment's levelness and the design of the weld teeth. While ensuring the weld quality, it is difficult to expand the effective area for metal-to-metal welding. Summary of the Invention

[0004] To address the aforementioned problems, the present invention aims to provide a welding method and welding equipment that reduces the thickness of the non-metallic layer within the electrode tab by extrusion before ultrasonic welding. This reduces the amount of non-metallic layer extruded during ultrasonic welding, thereby enabling the welding head for ultrasonic welding to form a smaller toothless area and a larger toothed area, thus expanding the effective welding area of ​​the foil and metal layer.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A welding method for welding tabs, the tabs comprising a non-conductive layer and conductive layers covering both sides of the non-conductive layer, the welding method comprising: heating the tabs to a predetermined temperature range to soften the non-conductive layer; bidirectionally extruding and shaping the heated tabs in the thickness direction to extrude a portion of the non-conductive layer within the tabs to reduce the thickness of the non-conductive layer; placing foil on the surface of at least one of the conductive layers; detecting the thickness of the non-conductive layer of the extruded and shaped tabs, and if the thickness of the non-conductive layer is within a predetermined range, performing ultrasonic welding; if the thickness of the non-conductive layer is outside the predetermined range, marking it and directly recycling it.

[0007] For example, in the welding method provided in at least one embodiment of the present invention, the moving path of the electrode tab is adjusted by a coil tension adjusting device so that the electrode tab is located on the same straight line during heating, extrusion shaping, foil placement, detection and ultrasonic welding.

[0008] For example, in the welding method provided in at least one embodiment of the present invention, the tension of the electrode tab is adjusted by a coil tension adjusting device.

[0009] For example, in the welding method provided in at least one embodiment of the present invention, the electrode tab is heated to 90°C-150°C.

[0010] For example, in the welding method provided in at least one embodiment of the present invention, the tab is unidirectionally heated by a heating mechanism, which is configured as at least one of a magnetic induction heating device, a hot air heating device, a radiation heating device, an infrared heating device, a microwave heating device, and a hot oil heating device.

[0011] A welding apparatus is provided for welding tabs, the tabs comprising a non-conductive layer and conductive layers covering both sides of the non-conductive layer. The welding apparatus includes an unwinding mechanism, a heating mechanism, a shaping mechanism, a foil placement mechanism, an ultrasonic welding mechanism, and a winding mechanism. The unwinding mechanism outputs the tab, which sequentially passes through the heating mechanism, the shaping mechanism, the foil placement mechanism, the ultrasonic welding mechanism, and the winding mechanism. The heating mechanism heats the non-conductive layer to a softened state. The shaping mechanism bidirectionally extrudes and shapes the tab in its thickness direction, extruding a portion of the non-conductive layer within the tab to reduce its thickness. The foil placement mechanism places foil on the surface of at least one of the conductive layers. The ultrasonic welding mechanism includes a welding head with a weld mark, the weld mark including a toothed area and a toothless area. The toothed area is used to weld the conductive layer and the foil, and the toothless area is used to accommodate and weld the non-conductive layer extruded during the welding process, the area of ​​the toothless area being smaller than the area of ​​the toothed area. The winding mechanism is used to retract the tab.

[0012] For example, in the welding equipment provided in at least one embodiment of the present invention, each of the weld teeth areas in the weld mark is distributed in a matrix.

[0013] For example, in the welding equipment provided in at least one embodiment of the present invention, the welding equipment further includes a detection mechanism disposed downstream of the shaping mechanism and upstream of the ultrasonic welding mechanism. The detection mechanism is used to detect the thickness of the non-conductive layer of the electrode after shaping. If the thickness of the non-conductive layer is within a predetermined range, the electrode is welded and then recycled to the winding mechanism. If the thickness of the non-conductive layer is outside the predetermined range, the electrode is marked and then directly recycled to the winding mechanism.

[0014] For example, in the welding equipment provided in at least one embodiment of the present invention, the electrode moves along a straight path and passes through the heating mechanism, the shaping mechanism, the foil placement mechanism, the detection mechanism and the ultrasonic welding mechanism.

[0015] For example, in the welding equipment provided in at least one embodiment of the present invention, the unwinding mechanism includes a coil unwinding roller, a coil unwinding drive roller, and a coil tension adjusting device. The coil unwinding roller is adapted to wind electrode coils. The coil unwinding drive roller is used to drive the coil unwinding roller to rotate. The coil tension adjusting device is used to change the movement path of the electrode and adjust the tension of the electrode. The coil tension adjusting device is configured as at least two, wherein a first one is located on the movement path of the electrode between the coil unwinding roller and the heating mechanism, and a second one is located on the movement path of the electrode between the ultrasonic welding mechanism and the winding mechanism. The first one, the heating mechanism, the shaping mechanism, the foil placement mechanism, the ultrasonic welding mechanism, and the second one are arranged sequentially along the same straight line.

[0016] For example, in the welding equipment provided in at least one embodiment of the present invention, the heating source of the heating mechanism is configured as at least one of a magnetic induction heating device, a hot air heating device, a radiant heating device, an infrared heating device, a microwave heating device, and a hot oil heating device; and / or

[0017] For example, in the welding equipment provided in at least one embodiment of the present invention, the electrode tab is heated to 90°C-150°C.

[0018] For example, in the welding equipment provided in at least one embodiment of the present invention, the shaping mechanism is located within or outside the heating area of ​​the heating mechanism.

[0019] For example, in the welding equipment provided in at least one embodiment of the present invention, the shaping mechanism includes two extruders for bidirectional extrusion shaping of the tab in the thickness direction, wherein at least one of the extruders is configured as a circular roller.

[0020] For example, in the welding equipment provided in at least one embodiment of the present invention, the outer peripheral surface of the circular roller is provided with a pattern, or the outer peripheral surface of the circular roller is provided with a smooth surface.

[0021] For example, in the welding apparatus provided in at least one embodiment of the present invention, the foil is welded to the upper and / or lower layer of the tab.

[0022] Because the present invention adopts the above technical solution, it has at least the following advantages:

[0023] I. In the welding method and welding equipment provided by the present invention, the thickness of the non-metallic layer inside the electrode tab is reduced by extrusion before ultrasonic welding. In this way, the amount of non-metallic layer extruded during the welding process can be reduced. As a result, the welding head for ultrasonic welding can form a toothless area with a smaller distribution area and a toothed area with a larger distribution area, thereby expanding the effective welding area of ​​the foil and metal layer and making the welding effect more stable.

[0024] Second, the increased welding area between metals increases the product's flow capacity.

[0025] Third, due to the early extrusion of the non-conductive layer, the welding head pressure required in the subsequent welding process is reduced.

[0026] Fourth, due to the early extrusion of the non-metallic layer, the overall welding parameters are reduced, while the service life of the welding head is increased.

[0027] Fifth, due to the reduction in welding area between non-metals and metals and the increase in welding area between metals, the power required for ultrasonic welding has limited adaptability. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of a welding method provided in at least one embodiment of the present invention;

[0029] Figure 2 A schematic diagram of the structure of the electrode lug coil welded by the welding equipment provided in at least one embodiment of the present invention;

[0030] Figure 3 This is a schematic diagram of the structure of the electrode tab in a welding device provided in at least one embodiment of the present invention;

[0031] Figure 4 This is a schematic diagram of the structure of the electrode tab in the welding equipment provided in at least one embodiment of the present invention after it has been squeezed.

[0032] Figure 5 This is a schematic diagram of the structure of the welding equipment provided in at least one embodiment of the present invention during welding.

[0033] Figure 6 This is a schematic diagram of the structure of a welding device provided in at least one embodiment of the present invention;

[0034] Figure 7 This is a schematic diagram of the weld mark structure of the welding equipment provided in at least one embodiment of the present invention;

[0035] Figure 8 This is a schematic diagram of the solder mark structure formed in the comparative example of the present invention.

[0036] Marked in the attached diagram:

[0037] 10-pole ear;

[0038] 101-Current collector;

[0039] 1011 - Conductive layer;

[0040] 1012 - Non-conductive layer;

[0041] 102-Active substance;

[0042] 1013 - The non-conductive layer after shaping;

[0043] 104-Foil;

[0044] 105 - Solder mark;

[0045] 1051 - Welding area;

[0046] 1052 - Toothless area;

[0047] 201-Unwinding mechanism;

[0048] 202 - Heating mechanism;

[0049] 203-Forming mechanism;

[0050] 204 - Welding mechanism;

[0051] 205 - Receiving mechanism;

[0052] 206 - Foil unwinding mechanism. Detailed Implementation

[0053] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0054] In the description of this invention, it should be noted that the terms "upper", "lower", "front", "rear", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the system or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0055] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "assembly," "setup," and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0056] Reference Figures 1 to 7 As shown, at least one embodiment of the present invention provides a welding method for welding a tab 10, the tab 10 including a non-conductive layer 1012 and a conductive layer 1011 covering both sides of the non-conductive layer 1012. For example, the welding method includes the following steps S100 to S400.

[0057] S100, heat the tab 10 to a predetermined temperature range to soften the non-conductive layer 1012;

[0058] S200, the heated tab 10 is bidirectionally extruded and shaped in the thickness direction of the tab 10, and part of the non-conductive layer 1012 inside the tab 10 is extruded to reduce the thickness of the non-conductive layer 1012.

[0059] S300, a foil 104 is placed on the surface of at least one conductive layer 1011;

[0060] S400: Detect the thickness of the non-conductive layer 1012 of the extruded tab 10. If the thickness of the non-conductive layer 1012 is within a predetermined range, perform ultrasonic welding. If the thickness of the non-conductive layer 1012 is outside the predetermined range, mark it and recycle it directly.

[0061] The welding head used for ultrasonic welding has a weld mark 105, which includes a toothed area 1051 and a toothless area 1052. The toothed area 1051 is used to weld the conductive layer 1011 and the foil 104, and the toothless area 1052 is used to accommodate and weld the non-conductive layer 1012 that is extruded during the welding process. The distribution area of ​​the toothless area 1052 is smaller than that of the toothed area 1051.

[0062] In the welding method of the above embodiment, by reducing the thickness of the non-metallic layer within the tab 10 through extrusion before ultrasonic welding, the amount of non-metallic layer extruded during the welding process can be reduced. Consequently, the welding head stamp 105 used for ultrasonic welding can form a smaller toothless area 1052 and a larger toothed area 1051, thereby expanding the effective welding area of ​​the foil 104 and the metal layer, and making the welding effect more stable. Furthermore, the increased welding area between metals increases the product's flow capacity. Due to the pre-extrusion of the non-conductive layer 1012, the welding head pressure required in subsequent welding processes is reduced, and the overall welding parameters are lowered, while the welding head's lifespan is increased. Furthermore, due to the reduced welding area between non-metals and the increased welding area between metals, the power required for ultrasonic welding can be adapted to a smaller range.

[0063] Specifically, in step S100, after the tab 10 is heated to a predetermined temperature, the non-conductive layer 1012 softens, allowing it to be extruded between the conductive layers 1011 on both sides. For example, the non-conductive layer 1012 is configured as plastic. For example, the predetermined temperature is configured as the melting point temperature of the plastic and the bottom temperature ±10°C.

[0064] For example, in step S200, when the heated tab 10 is bidirectionally extruded in the thickness direction of the tab 10, the conductive layers 1011 on both sides are recessed towards the non-conductive layer 1012 to a certain extent. Then, the non-conductive layer 1012 near the recessed area is squeezed out of the tab 10 under pressure. For example, when the non-conductive layer 1012 cools down and returns to a solid state, the tab 10 completes the extrusion shaping. It should be noted that the non-conductive layer 1012 still has a certain thickness after extrusion shaping. During subsequent ultrasonic welding, the non-conductive layer 1012, after melting, can still be squeezed out into the shallow weld zone.

[0065] For example, in step S300, the outer conductive layer 1011 places a foil 104 as an example adapter piece.

[0066] For example, in step S400, the thickness of the non-conductive layer 1012 of the extruded tab 10 is detected by a detection mechanism, and a predetermined thickness value is set to determine whether the tab 10 is ultrasonically welded before recycling or directly recycled after marking. For example, the predetermined thickness value is set according to the size of the conductive layer 1011, the size of the foil 104, and / or the size of the weld tooth area 1051 and the toothless area 1052.

[0067] For example, in the welding method provided in at least one embodiment of the present invention, the moving path of the tab 10 is adjusted by a coil tension adjusting device so that the tab 10 is located on the same straight line during heating, extrusion shaping, foil placement 104, inspection, and ultrasonic welding. It is understood that adjusting the tab 10 to move continuously along a straight path avoids path bends and tilts during the movement of the tab 10, which facilitates the heating, extrusion shaping, foil placement 104, inspection, and ultrasonic welding operations during the movement of the tab 10, and for example, improves the accuracy of the results of these operations.

[0068] For example, in the welding method provided in at least one embodiment of the present invention, the tension of the tab 10 is adjusted by a coil tension adjusting device. In this way, sufficient tension can be maintained during the movement of the tab 10, and slack or wobbling will not occur. This facilitates the heating operation, extrusion shaping operation, foil placement operation, inspection operation, and ultrasonic welding operation of the tab 10 during the movement process, and for example, improves the accuracy of the results of these operations.

[0069] For example, in the welding method provided in at least one embodiment of the present invention, the tab 10 is heated to 90°C-150°C, that is, the tab 10 can be heated to 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, or other values ​​among 90°C-150°C.

[0070] For example, in the welding method provided in at least one embodiment of the present invention, the tab 10 is unidirectionally heated by the heating mechanism 202, which is configured as, but not limited to, at least one of a magnetic induction heating device, a hot air heating device, a radiation heating device, an infrared heating device, a microwave heating device, and a hot oil heating device.

[0071] Reference Figures 2 to 7 As shown, at least one embodiment of the present invention provides a welding device for welding tabs 10. The tabs 10 include a non-conductive layer 1012 and a conductive layer 1011 covering both sides of the non-conductive layer 1012. The welding device includes an unwinding mechanism 201, a heating mechanism 202, a shaping mechanism 203, a foil placement mechanism 206, an ultrasonic welding mechanism 204, and a winding mechanism 205.

[0072] The unwinding mechanism 201 outputs the tab 10, which sequentially passes through the heating mechanism 202, the shaping mechanism 203, the foil placement mechanism 206, the ultrasonic welding mechanism 204, and the winding mechanism 205. The heating mechanism 202 heats the non-conductive layer 1012 to a softened state. The shaping mechanism 203 bidirectionally extrudes and shapes the tab 10 in its thickness direction, extruding a portion of the non-conductive layer 1012 within the tab 10 to reduce its thickness. The foil placement mechanism 206 places foil 104 on the surface of at least one conductive layer 1011. The ultrasonic welding mechanism 204 includes a welding head with a weld mark 105. The weld mark 105 includes a toothed area 1051 and a toothless area 1052. The toothed area 1051 is used to weld the conductive layer 1011 and the foil 104, and the toothless area 1052 is used to accommodate and weld the non-conductive layer 1012 that is extruded during the welding process. The distribution area of ​​the toothless area 1052 is smaller than that of the toothed area 1051. The winding mechanism 205 is used to retract the tab 10.

[0073] In the welding equipment of the above embodiment, by reducing the thickness of the non-metallic layer within the tab 10 through extrusion before ultrasonic welding, the amount of non-metallic layer extruded during the welding process can be reduced. Consequently, the welding head stamp 105 used for ultrasonic welding can form a smaller toothless area 1052 and a larger toothed area 1051, thereby increasing the effective welding area of ​​the foil 104 and the metal layer, and making the welding effect more stable. Furthermore, the increased welding area between metals increases the flow capacity of the product. Due to the pre-extrusion of the non-conductive layer 1012, the welding head pressure required in subsequent welding processes is reduced, and the overall welding parameters are lowered, while the service life of the welding head is increased. Furthermore, due to the reduced welding area between non-metals and the increased welding area between metals, the power required for ultrasonic welding can be adapted to a smaller range.

[0074] It should be noted that, in this embodiment of the invention, the weld tooth area 1051 is exposed on the surface of the toothless area 1052, and the area between two adjacent weld tooth areas 1051 is the toothless area 1052. The non-conductive layer 1012 is extruded and housed in the toothless area 1052. Each protruding weld tooth area 1051 can abut against the conductive layer 1011 and the foil 104.

[0075] For example, active material 102 is coated on current collector 101 (i.e. tab 10), and then rolled to form tab 10 roll material.

[0076] For example, after the tab 10 is heated to a predetermined temperature, the non-conductive layer 1012 softens, allowing it to be extruded between the conductive layers 1011 on both sides. For example, the non-conductive layer 1012 is configured as a plastic. For example, the predetermined temperature is configured as the melting point temperature of the plastic and the bottom temperature ±10°C.

[0077] For example, when the heated tab 10 is bidirectionally extruded along its thickness direction, the conductive layers 1011 on both sides are recessed towards the non-conductive layer 1012 to a certain extent. Then, the non-conductive layer 1012 near the recessed area is squeezed out of the tab 10 under pressure. For example, when the non-conductive layer 1012 cools down and returns to a solid state, the tab 10 completes its extrusion shaping. It should be noted that the non-conductive layer 1012 still has a certain thickness after extrusion shaping. During subsequent ultrasonic welding, the non-conductive layer 1012, after melting, can still be squeezed out into the shallow weld zone.

[0078] For example, the outer conductive layer 1011 may hold foil 104, which may be used as an adapter piece, for example.

[0079] For example, in the welding apparatus provided in at least one embodiment of the present invention, the weld tooth areas 1051 in the weld mark 105 are arranged in a matrix. For example, the shape of each weld tooth area 1051 can also be configured as rectangular. However, the design is not limited to this, and in other embodiments, each weld tooth area 1051 can also be configured as, for example, elliptical.

[0080] For example, in the welding equipment provided in at least one embodiment of the present invention, the welding equipment further includes a detection mechanism located downstream of the shaping mechanism 203 and upstream of the ultrasonic welding mechanism 204. The detection mechanism is used to detect the thickness of the non-conductive layer 1012 of the shaped electrode 10. If the thickness of the non-conductive layer 1012 is within a predetermined range, the electrode 10 is welded and then recycled to the winding mechanism 205. If the thickness of the non-conductive layer 1012 is outside the predetermined range, the electrode 10 is marked and then directly recycled to the winding mechanism 205.

[0081] For example, a predetermined thickness value is set. The testing agency determines whether the tab 10 should be ultrasonically welded before recycling or directly recycled after marking based on the comparison between the detected value and the predetermined thickness value. For instance, if the detected value is greater than the predetermined value, it is determined that the tab 10 corresponding to the detected value is unqualified in extrusion and shaping. The tab 10 is then marked and directly recycled by the winding mechanism 205. For example, the predetermined thickness value is set based on the size of the conductive layer 1011, the size of the foil 104, and / or the size of the weld tooth area 1051 and the toothless area 1052.

[0082] For example, in the welding apparatus provided in at least one embodiment of the present invention, the electrode 10 moves along a straight path, passing through the heating mechanism 202, the shaping mechanism 203, the foil placement mechanism 206, the detection mechanism, and the ultrasonic welding mechanism 204. It is understood that the electrode 10 is configured to move continuously along a straight path, avoiding path bends and tilts during its movement. This facilitates the heating, extrusion shaping, foil placement 104, detection, and ultrasonic welding operations of the electrode 10 during its movement, and for example, improves the accuracy of these operations.

[0083] For example, in the welding equipment provided in at least one embodiment of the present invention, the unwinding mechanism 201 includes a coil unwinding roller, a coil unwinding drive roller, and a coil tension adjusting device. The coil unwinding roller is adapted to wind the electrode 10 coil. The coil unwinding drive roller is used to drive the coil unwinding roller to rotate. The coil tension adjusting device is used to change the moving path of the electrode 10 and adjust the tension of the electrode 10. The coil tension adjusting device is configured as at least two, wherein the first one is located on the moving path of the electrode 10 between the coil unwinding roller and the heating mechanism 202, and the second one is located on the moving path of the electrode 10 between the ultrasonic welding mechanism 204 and the winding mechanism 205. The first one, the heating mechanism 202, the shaping mechanism 203, the foil placement mechanism 206, the ultrasonic welding mechanism 204, and the second one are arranged sequentially along the same straight line.

[0084] In this embodiment, the movement speed of the electrode 10 can be controlled by adjusting the rotation speed of the unwinding drive roller. A moderate movement speed of the electrode 10 ensures that the heating, extrusion and shaping, foil placement, inspection, and ultrasonic welding operations of the electrode 10 proceed smoothly. Furthermore, the unwinding drive roller can be adjusted to start and stop based on the inspection results from the inspection mechanism.

[0085] Furthermore, the first and second components of the roll tension adjusting device straighten the tab 10 in opposite directions, allowing the tab 10 to pass along a straight path through the heating mechanism 202, the shaping mechanism 203, the foil placement mechanism 206, the detection mechanism, and the ultrasonic welding mechanism 204. Even further, the roll tension adjusting device ensures that the tab 10 maintains sufficient tension during movement, preventing slackness or wobbling. This facilitates the heating, extrusion shaping, foil placement 104, detection, and ultrasonic welding operations during the tab 10's movement, thereby improving the accuracy of these operations.

[0086] For example, in the welding equipment provided in at least one embodiment of the present invention, the heating source of the heating mechanism 202 is configured as, but not limited to, at least one of a magnetic induction heating device, a hot air heating device, a radiation heating device, an infrared heating device, a microwave heating device, and a hot oil heating device.

[0087] For example, in the welding equipment provided in at least one embodiment of the present invention, the tab 10 is heated to 90°C-150°C, that is, the tab 10 can be heated to 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, or other values ​​among 90°C-150°C.

[0088] For example, in the welding equipment provided in at least one embodiment of the present invention, the shaping mechanism 203 is located within or outside the heating area of ​​the heating mechanism 202. Understandably, when the shaping mechanism 203 is located within the heating area of ​​the heating mechanism 202, the non-conductive layer 1012, after heating, can be promptly shaped by the shaping mechanism 203 if it is not yet shaped. When the shaping mechanism 203 is located outside the heating area of ​​the heating mechanism 202, the non-conductive layer 1012, after heating, can remain in a softened state for a period of time even after moving away from the heating area, and is shaped by the shaping mechanism 203 outside the heating area. In this case, the solidification rate of the non-conductive layer 1012 is not significantly affected by the decrease in temperature.

[0089] For example, in the welding equipment provided in at least one embodiment of the present invention, the shaping mechanism 203 includes two extruders for bidirectional extrusion shaping of the tab 10 in the thickness direction, wherein at least one extruder is configured as a circular roller. During the extrusion process, the circular roller can maintain a continuous rotation state, thereby enabling low-resistance extrusion operation on the tab 10 during movement.

[0090] For example, in the welding equipment provided in at least one embodiment of the present invention, the outer peripheral surface of the circular roller is provided with a pattern, or the outer peripheral surface of the circular roller is provided as a smooth surface. It is understood that providing the outer peripheral surface of the circular roller as a smooth surface can reduce the resistance to the movement of the tab 10.

[0091] For example, in the welding apparatus provided in at least one embodiment of the present invention, foil 104 is welded to the upper and / or lower layer of tab 10.

[0092] Below is a comparative example of the welding method and welding equipment provided by embodiments of the present invention:

[0093] Reference Figure 8 As shown, the electrode roll, composed of current collector and active material, is placed on an ultrasonic welding machine via an unwinding mechanism; the electrode and foil are welded together to form a weld mark 105. Since the comparative example did not undergo the processing described in the embodiments of this invention, the area of ​​the toothed region 1051 in the weld mark 105 is smaller, while the area of ​​the toothless region 1052 is larger.

[0094] Welding pressure (bar) Welding amplitude (%) Resistance (mΩ) Example 2.5 30 15 Comparative Example 1.5 28 10

[0095] Table 1

[0096] Table 1 shows the welding data obtained from the embodiments and comparative examples of the present invention.

[0097] In the welding method and welding equipment provided in this embodiment of the invention, the increased welding area of ​​the conductive layer 1011 in the weld mark 105 reduces the welding resistance, lowers the overall welding parameters used, and increases the service life of the subsequent welding head.

[0098] It should be noted that the "and / or" in the text includes three options. Taking "A and / or B" as an example, it includes technical option A, technical option B, and technical option that satisfies both A and B.

[0099] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A welding method using a welding device, the welding device being used for welding electrode tabs, the electrode tabs comprising a non-conductive layer and a conductive layer covering both sides of the non-conductive layer, wherein... The welding equipment includes an unwinding mechanism, a heating mechanism, a shaping mechanism, a foil placement mechanism, an ultrasonic welding mechanism, and a winding mechanism; The unwinding mechanism is used to output the electrode tab, which moves along a straight path and passes sequentially through the heating mechanism, the shaping mechanism, the foil placement mechanism, the ultrasonic welding mechanism, and the winding mechanism. The heating mechanism is used to heat the non-conductive layer to a softened state; The shaping mechanism is used to bidirectionally extrude and shape the tab in the thickness direction, thereby extruding a portion of the non-conductive layer within the tab to reduce the thickness of the non-conductive layer; specifically, the shaping mechanism includes two extruders for bidirectionally extruding and shaping the tab in the thickness direction, wherein at least one of the extruders is configured as a circular roller. The foil placement mechanism is used to place foil on the surface of at least one of the conductive layers, the foil being used to be soldered to the upper and / or lower layers of the electrode tab; The ultrasonic welding mechanism includes a welding head for welding the metal layer of the electrode tab of the foil; The winding mechanism is used to retract the electrode tab; The welding head is characterized by having a weld mark, which includes a toothed area and a toothless area. The toothed area is used to weld the conductive layer and the foil, and the toothless area is used to accommodate and weld the non-conductive layer that is extruded during the welding process. The area of ​​the toothless area is smaller than the area of ​​the toothed area. The toothed area is exposed on the surface of the toothless area, and the area between two adjacent toothed areas is a toothless area. The toothed areas in the weld mark are arranged in a matrix. The welding equipment also includes a detection mechanism located downstream of the shaping mechanism and upstream of the ultrasonic welding mechanism. The detection mechanism is used to detect the thickness of the non-conductive layer of the electrode after shaping. If the thickness of the non-conductive layer is within a predetermined range, the electrode is welded and then recycled to the winding mechanism. If the thickness of the non-conductive layer is outside the predetermined range, the electrode is marked and then directly recycled to the winding mechanism. The welding method includes: S100: Heat the tab to a predetermined temperature range to soften the non-conductive layer; S200: The heated electrode is bidirectionally extruded and shaped in the thickness direction of the electrode tab, thereby extruding a portion of the non-conductive layer inside the electrode tab to reduce the thickness of the non-conductive layer; wherein, the non-conductive layer is a non-metallic layer, and after being extruded, the non-conductive layer is housed in a toothless area, and the protruding welding teeth can abut against the conductive layer and the foil; the soldering forms a toothless area with a smaller distribution area and a welding teeth area with a larger distribution area, thereby expanding the effective welding area of ​​the foil and the metal layer, and making the welding effect more stable; S300: A foil is placed on the surface of at least one of the conductive layers; S400: Detect the thickness of the non-conductive layer of the electrode after extrusion and shaping. If the thickness of the non-conductive layer is within a predetermined range, perform ultrasonic welding. If the thickness of the non-conductive layer is outside the predetermined range, mark it and recycle it directly. The movement path of the electrode tabs is adjusted by a roll tension adjustment device to ensure that the electrode tabs are all on the same straight line during heating, extrusion shaping, foil placement, testing, and ultrasonic welding; and / or The tension of the tabs is adjusted by the roll tension adjusting device; and / or The electrode tab is heated to 90℃-150℃; and / or The electrode tab is unidirectionally heated by a heating mechanism, which is configured as at least one of a magnetic induction heating device, a hot air heating device, a radiation heating device, an infrared heating device, a microwave heating device, and a hot oil heating device.

2. The welding method according to claim 1, characterized in that, The unwinding mechanism includes a roll unwinding roller, a roll unwinding drive roller, and a roll tension adjusting device. The roll unwinding roller is adapted to wind tab roll material. The roll unwinding drive roller is used to drive the roll unwinding roller to rotate. The roll tension adjusting device is used to change the movement path of the tab and adjust the tension of the tab. The roll tension adjusting device is configured as at least two, with a first one located on the movement path of the tab between the roll unwinding roller and the heating mechanism, and a second one located on the movement path of the tab between the ultrasonic welding mechanism and the winding mechanism. The first device, the heating mechanism, the shaping mechanism, the foil placement mechanism, the ultrasonic welding mechanism, and the second device are arranged sequentially along the same straight line.

3. The welding method according to any one of claims 1 to 2, characterized in that, The heating source of the heating mechanism is configured as at least one of a magnetic induction heating device, a hot air heating device, a radiant heating device, an infrared heating device, a microwave heating device, and a hot oil heating device; and / or The shaping mechanism is located either within or outside the heating area of ​​the heating mechanism.

4. The welding method according to any one of claims 1 to 2, characterized in that, The outer circumferential surface of the circular roller is patterned, or the outer circumferential surface of the circular roller is made smooth.

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