Welding apparatus and welding method for back contact cells

Abstract

The application belongs to the technical field of battery welding, and discloses a welding device and a welding method for back contact batteries. The welding device for back contact batteries comprises a welding main body, a welding strip conveying unit, a battery piece transplanting unit and a welding unit. The welding main body is provided with a welding heat transfer carrier and a welding strip fixing member. The welding strip conveying unit sends a plurality of parallel welding strips with bus bars at both ends to the welding heat transfer carrier. The welding strip fixing member fixes the bus bars to prevent the welding strips from being straight. The battery piece transplanting unit can grab a plurality of battery pieces and press the back surfaces of the battery pieces to the welding strips on the welding heat transfer carrier. The plurality of battery pieces are arranged in parallel and at intervals along the extension direction of the welding strips. The welding unit is located below the welding heat transfer carrier. The welding unit can move back and forth in the vertical direction to weld the plurality of battery pieces and the plurality of parallel welding strips. The damage and scratches of the welding strips in the accommodating groove can be avoided. The welding rate and the heat dissipation rate of the welding strips are consistent, and false welding or welding separation is avoided.

Description

Technical Field

[0001] This invention relates to the field of battery welding technology, and in particular to a welding apparatus and welding method for a back contact battery. Background Technology

[0002] In existing back-contact (BC) batteries, the electrode grid lines are all located on the back of the battery, as are the PN junction and metal contact plates. This reduces the shading of sunlight by the battery grid lines, maximizes the utilization of incident light, reduces optical loss, and improves the battery's conversion efficiency. Therefore, when BC batteries are wired together, solder ribbons coated with solder paste are usually used for soldering. However, due to the light weight of the solder ribbons, they are prone to misalignment when soldering to the battery cells, resulting in soldering misalignment, reduced soldering quality, increased soldering workload, and decreased soldering efficiency.

[0003] In related technologies, a battery string welding device and welding method are provided. The battery string welding device includes a welding support device, a solder ribbon laying device, and a battery cell laying device. The welding support device includes multiple support platforms, each capable of supporting one battery cell. The solder ribbon laying device lays multiple solder ribbons side by side into multiple solder ribbon receiving grooves within the multiple support platforms. The battery cell laying device lays multiple battery cells with their backs facing down on the multiple support platforms, so that the battery cells are pressed onto multiple solder ribbons. However, if there are burrs on the edge of the receiving groove when the solder ribbon is placed in the receiving groove, they can scratch the tin coating on the surface of the solder ribbon during the laying process, resulting in insufficient tin layer fluidity during welding, affecting the strength of the solder joint. Furthermore, the receiving groove can create a cavity under the solder ribbon. During welding, the solder ribbon located in the receiving groove has a different heat dissipation rate than the solder ribbon in other parts, leading to poor soldering or desoldering at the solder joint between the solder ribbon and the battery cell, resulting in uneven welding quality. Summary of the Invention

[0004] The purpose of this invention is to provide a welding apparatus and welding method for back contact batteries. This method ensures the welding strip remains straight, preventing damage and scratches within the receiving groove. It also ensures complete contact between the welding strip and the heat transfer bearing component, preventing the formation of cavities. Furthermore, it maintains consistent welding and heat dissipation rates, avoiding incomplete welds or detachment, and thus improving welding quality.

[0005] To achieve this objective, the present invention adopts the following technical solution:

[0006] A welding apparatus for the back contact battery, comprising:

[0007] A welding body, wherein a welding heat transfer bearing component and a welding strip fixing component are provided on the welding body;

[0008] A welding strip conveying unit is configured to convey multiple parallel welding strips to the welding heat transfer bearing, and each of the multiple parallel welding strips is connected to a busbar at both ends. The welding strip fixing member fixes the busbars at both ends of the welding strips to keep the multiple parallel welding strips straight.

[0009] A battery cell transfer unit is disposed on the side of the welding body. The battery cell transfer unit can grasp multiple battery cells and press them onto the welding strip located on the welding heat transfer support, so that the back of the battery cell is in contact with the welding strip. The multiple battery cells are arranged in parallel and spaced along the extension direction of the welding strip.

[0010] The welding unit is located below the welding heat transfer support and is capable of reciprocating in the vertical direction to weld multiple battery cells and multiple parallel welding strips.

[0011] Preferably, the welding heat transfer bearing member has multiple fixing grooves extending along the conveying direction of the welding strip, and the multiple fixing grooves are spaced apart along the extension direction of the welding strip. The welding device for the back contact battery further includes:

[0012] A fixing unit is disposed on the welding body, and the output end of the fixing unit can pass through the fixing groove and be fixedly connected to multiple parallel welding strips.

[0013] Preferably, the welding heat transfer bearing is transparent tempered glass.

[0014] Preferably, the welding unit includes:

[0015] Welding drive components;

[0016] The welded component is connected to the output end of the welding drive component, which is capable of driving the welded component to reciprocate in the vertical direction.

[0017] Preferably, the welding device for the back contact battery further includes:

[0018] A ribbon breaking unit is provided, which is spaced apart from the welding body. The cell transfer unit can transfer multiple welded cells and multiple parallel ribbons to the ribbon breaking unit. The ribbon breaking unit is used to break part of the ribbon between two adjacent cells to form a battery string.

[0019] Preferably, the solder strip breaking unit further includes:

[0020] A ribbon breaking platform is provided with multiple breaking grooves extending along the conveying direction of the ribbon, and the multiple breaking grooves are arranged at intervals along the extension direction of the ribbon. The projections of multiple parallel ribbons connecting the middle of two adjacent solar cells are located in the breaking grooves along a direction perpendicular to the solar cell.

[0021] A ribbon breaking component is provided on the ribbon breaking platform. The output end of the ribbon breaking component can pass through the breaking groove to break part of the ribbon between two adjacent battery cells.

[0022] Preferably, the welding device for the back contact battery further includes:

[0023] A collection unit is provided on the ribbon breaking platform, and the collection unit is used to collect the ribbon broken by the ribbon breaking component.

[0024] Preferably, the solder strip breaking unit includes:

[0025] A battery cell conveying platform is provided, which is spaced apart from the welding ribbon breaking platform. The battery cell transfer unit is capable of transferring multiple welded battery cells and multiple parallel welding ribbons to the battery cell conveying platform. The battery cell conveying platform is capable of temporarily holding the multiple welded battery cells and multiple parallel welding ribbons.

[0026] Preferably, the welding device for the back contact battery further includes:

[0027] A visual inspection unit is electrically connected to the welding conveying unit and the welding strip conveying unit. The visual inspection unit is used to detect the position of the welding strip on the welding heat transfer support.

[0028] A method for welding a back contact battery, the method utilizing the welding apparatus for a back contact battery as described above, the method comprising:

[0029] S1: The welding strip conveying unit conveys multiple parallel welding strips connected to the busbars at opposite ends to the welding heat transfer bearing;

[0030] S2: The welding strip fastener secures the two busbars;

[0031] S3: The battery cell transfer unit presses multiple battery cells onto the welding strip located on the welding heat transfer support, so that the back of the battery cell is in contact with the welding strip;

[0032] S4: The welding unit rises to weld multiple of the battery cells and multiple parallel welding strips.

[0033] The beneficial effects of this invention are:

[0034] This invention provides a welding apparatus and method for back-contact batteries. The welding apparatus includes a welding body, a welding strip conveying unit, a cell transfer unit, and a welding unit. The welding body is provided with a welding heat transfer bearing and a welding strip fixing component. The welding strip conveying unit is configured to convey multiple parallel welding strips to the welding heat transfer bearing, and each of the opposite ends of the multiple parallel welding strips is connected to a busbar. The welding strip fixing component fixes the busbars at opposite ends of the welding strips to keep the multiple parallel welding strips straight. The cell transfer unit is located beside the welding body and can grasp multiple cells and press them onto the welding strips located on the welding heat transfer bearing, so that the back of the cells is in contact with the welding strips. The multiple cells are arranged in parallel intervals along the extension direction of the welding strips. The welding unit is located below the welding heat transfer bearing and can reciprocate in the vertical direction to weld multiple cells and multiple parallel welding strips.

[0035] The welding strip conveying unit delivers parallel welding strips with busbars to the welding heat transfer support. The welding strip fixing component secures the busbars, ensuring the welding strip is straight. The cell transfer unit picks up the cell and presses it onto the welding strip at a preset position, ensuring close contact between the cell and the welding strip. The welding unit rises from below to weld the bonded cell and welding strip, then descends to await the next welding cycle. The design of the welding heat transfer support and welding strip fixing component ensures that the multiple welding strips placed on the welding heat transfer support remain straight, preventing damage and scratches to the welding strips within the receiving groove. Simultaneously, it presses the back of the cell onto the straight welding strip. Maintaining close contact between the cell and the welding strip, the welding heat transfer support ensures complete contact between the welding strip and the support, preventing cavities and ensuring consistent welding and heat dissipation rates. This avoids incomplete welds or detachment, contributing to improved welding quality. Attached Figure Description

[0036] Figure 1 This is a first schematic diagram of the welding device for a back contact battery provided in an embodiment of the present invention;

[0037] Figure 2 This is a second schematic diagram of the welding device for the back contact battery provided in an embodiment of the present invention;

[0038] Figure 3 This is a third schematic diagram of the welding device for the back contact battery provided in an embodiment of the present invention.

[0039] In the picture:

[0040] 1. Welding body; 11. Welding heat transfer bearing component; 12. Welding strip fixing component;

[0041] 2. Cell transfer unit;

[0042] 3. Welding unit; 31. Welded component;

[0043] 4. Welding strip breaking unit; 41. Breaking groove. Detailed Implementation

[0044] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0045] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; 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; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0046] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0047] In the description of this embodiment, the terms "upper," "lower," "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device 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 the present invention. In addition, the terms "first" and "second" are used only for distinction in description and have no special meaning.

[0048] This embodiment provides a welding device for back-contact batteries, including a welding body 1, a welding strip conveying unit, a battery cell transfer unit 2, and a welding unit 3. The welding body 1 is provided with a welding heat transfer bearing 11 and a welding strip fixing member 12. The welding strip conveying unit is configured to convey multiple parallel welding strips to the welding heat transfer bearing 11, and each of the two ends of the multiple parallel welding strips is connected to a busbar. The welding strip fixing member 12 fixes the busbars at the two ends of the welding strips to keep the multiple parallel welding strips straight. The battery cell transfer unit 2 is located beside the welding body 1. The battery cell transfer unit 2 can grasp multiple battery cells and press them onto the welding strips located on the welding heat transfer bearing 11 so that the back of the battery cells is in contact with the welding strips. The multiple battery cells are arranged in parallel and spaced along the extension direction of the welding strips. The welding unit 3 is located below the welding heat transfer bearing 11. The welding unit 3 can reciprocate in the vertical direction to weld multiple battery cells and multiple parallel welding strips.

[0049] The welding strip conveying unit delivers parallel welding strips with busbars to the welding heat transfer support 11. The welding strip fixing component 12 secures the busbars, ensuring the welding strip is straight. The cell transfer unit 2 picks up the cell and presses it onto the welding strip at a preset position, ensuring the cell and welding strip are in close contact. The welding unit 3 rises from below to weld the adhered cell and welding strip, then descends to await the next welding cycle. The design of the welding heat transfer support 11 and welding strip fixing component 12 ensures that the multiple welding strips placed on the welding heat transfer support 11 remain straight, preventing damage and scratches to the welding strips within the receiving groove and preventing the welding strips from shifting. Simultaneously, it presses the back of the cell onto the straight welding strip. While maintaining the adhesion between the cell and the welding strip, the welding heat transfer support 11 ensures complete contact between the welding strip and the support 11, preventing the formation of cavities. This ensures that the welding rate and heat dissipation rate of the welding strip remain consistent, avoiding incomplete welds or detachment, and contributing to improved welding quality.

[0050] Specifically, such as Figure 1 As shown, in this embodiment, 16 solder strips are provided. In other embodiments, 12 or 18 solder strips are provided, etc. No limitation is made here. It should be noted that in this embodiment, the solder strips are flat solder strips. In other embodiments, the solder strips are circular solder strips or trapezoidal solder strips, etc. No limitation is made here.

[0051] Specifically, in this embodiment, the solder strip is welded to the busbar. In other embodiments, the solder strip and the busbar are riveted or crimped. No limitations are imposed here.

[0052] Specifically, such as Figure 1 As shown, in this embodiment, 10 battery cells are provided. In other embodiments, 10 or 12 battery cells are provided, etc. No limitation is made here.

[0053] Optionally, such as Figure 1 As shown, the welding heat transfer bearing 11 has multiple fixing grooves (not shown in the figure) extending along the conveying direction of the welding strip, and the multiple fixing grooves are arranged at intervals along the extension direction of the welding strip. The welding device for back contacting the battery also includes a fixing unit (not shown in the figure). The fixing unit is disposed on the welding body 1, and the output end of the fixing unit can pass through the fixing groove and be fixedly connected to multiple parallel welding strips. After the welding strip with the busbar is kept straight by fixing the busbar, the output end of the fixing unit passes through the fixing groove and is fixedly connected to multiple parallel welding strips. By fixing at multiple points in the middle of each welding strip, the straightness of the welding strip can be further maintained, and welding offset caused by the non-straightness of the welding strip in the middle position can be further avoided.

[0054] Specifically, in this embodiment, nine fixing slots are provided. Along a direction perpendicular to the solar cells, the projections of multiple parallel solder strips connecting the middle of adjacent solar cells are located within the fixing slots. This arrangement ensures that both ends of the solder strips are fixed, effectively preventing displacement of the solder strips during subsequent welding, avoiding obstruction of current transmission between solar cells, and guaranteeing welding efficiency. In other embodiments, six, eight, or ten fixing slots are provided, etc. No limitation is made here.

[0055] Specifically, in this embodiment, the fixing unit includes a movable component and multiple fixing clamps. The movable component is disposed on the welding body 1, and the multiple fixing clamps are connected to the output end of the movable component. The movable component can drive the multiple fixing clamps to simultaneously fix multiple parallel welding strips in the middle of two adjacent battery cells.

[0056] Specifically, regarding the existing structure of the moving component, the moving component in this embodiment can be any type of existing moving component, capable of driving multiple fixing clamps to simultaneously fix multiple parallel welding strips in the middle of two adjacent battery cells. No restrictions are imposed here.

[0057] Specifically, in this embodiment, 144 fixing clamps are provided, forming a 16x9 rectangular array, which can fix the 16 parallel solder strips between two adjacent battery cells. In other embodiments, the fixing clamps are formed in a 12x9 rectangular array, or a 12x6 rectangular array, etc. No limitation is made here.

[0058] Specifically, in this embodiment, the welding heat transfer bearing 11 is transparent tempered glass. The transparent tempered glass can both transfer the welding energy of the welding unit 3 and allow observation of the welding process of the battery cell and the welding strip from the direction of the welding unit 3. In other embodiments, the welding heat transfer bearing 11 may be an alumina ceramic sheet, etc. There are no limitations here, as long as it can transfer the welding energy of the welding unit 3 without affecting the welding process.

[0059] Optionally, the battery cell transfer unit 2 includes a robotic arm and multiple suction components. The robotic arm is positioned beside the welding body 1, and the multiple suction components are fixedly connected to the end of the robotic arm. These suction components can pick up multiple battery cells. The robotic arm drives the multiple suction components at its end to move to the battery cell storage area, and the suction components simultaneously pick up multiple battery cells. Then, the robotic arm moves the battery cells onto multiple welding strips on the welding heat transfer support 11 and presses the battery cells onto the welding strips, so that the back of the battery cell is in contact with the welding strips. It should be noted that there are 10 suction components. In other embodiments, there are 8 or 12 suction components, etc. There is no limitation here; the number can be the same as the number of battery cells.

[0060] Specifically, in this embodiment, the suction component includes an air pump, a suction cup, and a support. The support is fixedly connected to the output end of the robotic arm, the suction cup is snapped onto the support, and the suction cup and the air pump are connected and communicate with each other through an air pipe.

[0061] Optionally, such as Figures 1-3 As shown, welding unit 3 includes a welding drive and a welding component 31. The welding component 31 is connected to the output end of the welding drive, which drives the welding component 31 to reciprocate vertically. The welding drive, as a power source, drives the welding component 31 to reciprocate vertically. This movement allows the welding component 31 to move up and down vertically, thus meeting the welding requirements at different positions that may be needed during the welding process, such as switching between welding points at different heights.

[0062] Specifically, such as Figures 1-3 As shown, in this embodiment, the welding component 31 is a welding light box. In other embodiments, the welding component 31 can also be a laser welder, etc. No limitations are imposed here.

[0063] Specifically, in one embodiment, the welding drive is a linear motor, and the welding component 31 is fixedly connected to the output end of the linear motor. In other embodiments, the welding drive is a telescopic cylinder, and the welding component 31 is fixedly connected to the piston rod of the telescopic cylinder; or the welding drive is a rotary motor, and the welding component 31 is connected to the output end of the rotary motor via a gear and rack; or the welding drive is a rotary motor, and the welding component 31 is connected to the output end of the rotary motor via a sprocket and chain, etc. No limitations are imposed here.

[0064] Optionally, the welding device for the back contact battery also includes a ribbon cutting unit 4, which is spaced apart from the welding body 1. The cell transfer unit 2 can transfer multiple welded cells and multiple parallel ribbons to the ribbon cutting unit 4. The ribbon cutting unit 4 is used to cut a portion of the ribbon between two adjacent cells to form a battery string. Since the cells are in a short-circuit state after welding multiple cells and multiple ribbons, after welding multiple cells and multiple ribbons, for the nth cell, all odd-numbered ribbons between the nth and (n+1)th cells are cut, and all even-numbered ribbons between the (n-1)th and nth cells are cut. This alternating odd and even cutting method ensures that the cells form a battery string connected in series. After cutting a portion of the ribbon between two adjacent cells, multiple cells are connected in series through multiple ribbons to form a battery string, increasing the welding speed of the battery string.

[0065] Optionally, the solder ribbon breaking unit 4 includes a cell conveying platform. The cell transfer unit 2 can transfer multiple welded cells and multiple parallel solder ribbons to the cell conveying platform, which can temporarily hold the welded cells and multiple parallel solder ribbons. After the welding process is completed, multiple cells are connected into a single assembly by multiple parallel solder ribbons. The cell transfer unit 2 is activated, and the assembly is moved from the welding heat transfer support 11 to the cell conveying platform by means of gripping, adsorption, etc. The cell conveying platform receives and temporarily stores the assembly, and cools it on the platform. During the welding of the cells and solder ribbons, the solder ribbon melts the tin layer at high temperature, forming a metallurgical bond with the main grid lines of the cells. The cooling process allows the molten tin layer to solidify quickly, forming a strong and stable solder joint between the solder ribbon and the cells. If the cooling is not timely or uniform, the slow solidification of the tin layer may lead to a loose solder joint structure, or even problems such as solder ribbon misalignment and cold solder joints. Reduced welding strength affects the mechanical stability of the battery string; and since battery cells are brittle materials, the high temperature during welding causes localized thermal expansion of the cells. If they are directly exposed to air and cooled slowly, the thermal stress cannot be released quickly, which can easily lead to defects such as microcracks and fragmentation of the cells. Uniform cooling can reduce the accumulation of thermal stress and reduce the damage to the cells caused by temperature gradients. At the same time, the welding strip will deform to a certain extent due to thermal expansion and contraction at high temperatures. If it is not cooled in time, the welding strip may undergo secondary deformation such as bending or displacement under its own tension or external force, resulting in problems such as uneven spacing of the battery string. Cooling can quickly fix the shape and position of the welding strip, ensure the geometric accuracy of the battery string, and avoid secondary deformation of the welding strip.

[0066] Optionally, the ribbon cutting unit 4 also includes a ribbon cutting platform and a ribbon cutting assembly. The ribbon cutting platform is spaced apart from the cell conveying platform. The ribbon cutting platform has multiple cutting grooves 41 extending along the conveying direction of the ribbon, and these grooves are spaced apart. The projections of multiple parallel ribbons connecting two adjacent cells in a direction perpendicular to the cell lie within the cutting grooves 41. The ribbon cutting assembly is positioned on the ribbon cutting platform, and its output end can pass through the cutting grooves 41 to cut a portion of the ribbon between two adjacent cells. The projections of the multiple parallel ribbons between two adjacent cells in a direction perpendicular to the cell fall precisely within these cutting grooves 41. This design provides an "operating channel" for the ribbon cutting assembly, ensuring it can accurately act on the target ribbon without contacting the cell or other components, thus precisely cutting redundant ribbons between two adjacent cells and preventing open circuits between cells.

[0067] Specifically, in this embodiment, the ribbon cutting component is a laser cutter. Laser cutters offer high cutting precision and do not contact the battery cells, reducing the risk of fragmentation. In other embodiments, the ribbon cutting component can also be an integrated pneumatic shearing mechanism or a micro-blade cutter, etc. No limitations are imposed here.

[0068] Optionally, the welding device for the back contact battery also includes a collection unit located on the ribbon cutting platform. The collection unit is used to collect the ribbons cut by the ribbon cutting component. The electrodes of the back contact battery are located on the back side, and the ribbons are also located on the back side. The collection unit simultaneously processes the cut ribbons and collects them to prevent ribbon fragments from scattering and affecting equipment operation, thereby improving the automation level of the device and ensuring production continuity and cleanliness.

[0069] Specifically, the collection unit includes a robotic arm mechanism and a waste bin. The robotic arm mechanism collects the cut welding strip and places it in the waste bin.

[0070] More specifically, regarding the existing robotic arm structure, the robotic arm structure in this embodiment can adopt any existing robotic arm structure that can achieve the collection of cut welding strips. Further details will not be elaborated here.

[0071] Optionally, the welding device for the back contact battery also includes a vision inspection unit. The vision inspection unit is electrically connected to the welding conveying unit and the welding strip conveying unit. The vision inspection unit is used to detect the position of the welding strip on the welding heat transfer support 11. By setting up the vision inspection unit, when the welding strip conveying unit moves the welding strip to the welding heat transfer support 11, it can detect whether the placement of the welding strip is in the preset position. This avoids the welding strip not being placed in the preset position, which would reduce the effective contact area between the battery cell and the welding strip during welding, leading to uneven heat distribution and potential localized incomplete welding. This results in insufficient connection strength between the battery cell and the welding strip, and the strip may detach due to slight vibration or external force during subsequent use. Furthermore, the main function of the welding strip is to conduct current; positional deviation will lengthen or obstruct the current path, increasing the internal resistance of the module. This not only reduces the power generation efficiency of the battery module but may also cause overheating due to localized current concentration, affecting the overall lifespan and safety of the module.

[0072] This embodiment also provides a welding method for a back contact battery. The welding method for the back contact battery utilizes a welding device for the back contact battery and includes:

[0073] S1: The welding strip conveying unit conveys multiple parallel welding strips connected to each other at opposite ends to the welding heat transfer bearing 11;

[0074] S2: Welding strip fastener 12 secures two busbars;

[0075] S3: The cell transfer unit 2 presses multiple cells onto the welding strip located on the welding heat transfer support 11, so that the back of the cell is in contact with the welding strip;

[0076] S4: Welding unit 3 rises to weld multiple battery cells and multiple parallel welding strips.

[0077] By using a welding device that contacts the battery back to weld the battery cells and the welding strip, damage and scratches to the welding strip in the receiving groove are avoided, and the welding strip is prevented from shifting. At the same time, the back of the battery cell is pressed onto the flat welding strip. While maintaining the fit between the battery cell and the welding strip, the welding heat transfer bearing 11 ensures that the welding strip and the welding heat transfer bearing 11 are in complete contact without forming a cavity. This ensures that the welding rate and heat dissipation rate of the welding strip are consistent, avoiding incomplete welding or desoldering, and helping to improve the welding quality.

[0078] The following is combined Figures 1-3 This section describes the complete welding method for back contact batteries:

[0079] S1: The welding strip conveying unit conveys multiple parallel welding strips connected to each other at opposite ends to the welding heat transfer bearing 11;

[0080] S2: Welding strip fastener 12 secures two busbars;

[0081] S3: The cell transfer unit 2 presses multiple cells onto the welding strip located on the welding heat transfer support 11, so that the back of the cell is in contact with the welding strip;

[0082] S4: The welding drive unit drives the welding component 31 to rise, welding multiple battery cells and multiple parallel welding strips;

[0083] S5: The cell transfer unit 2 transfers multiple welded cells and multiple parallel welding strips to the cell transport platform and cools them on the cell transport platform.

[0084] S6: Multiple battery cells and multiple parallel solder ribbons move to the solder ribbon breaking platform. The solder ribbon breaking component moves to break part of the solder ribbon between two adjacent battery cells, so that multiple battery cells are connected in series through multiple solder ribbons to form a battery string.

[0085] Between S2 and S3, there is also:

[0086] S2-1: The output end of the fixed unit passes through the fixed groove and is fixedly connected to multiple parallel welding strips.

[0087] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art will be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A welding apparatus for a back contact battery, characterized in that, include: The welding body (1) is provided with a welding heat transfer bearing (11) and a welding strip fixing component (12); A welding strip conveying unit is configured to convey multiple parallel welding strips to the welding heat transfer bearing (11), and each of the two ends of the multiple parallel welding strips is connected to a busbar. The welding strip fixing member (12) fixes the busbars at the two ends of the welding strips so that the multiple parallel welding strips remain straight. A battery cell transfer unit (2) is disposed on the side of the welding body (1). The battery cell transfer unit (2) can grab multiple battery cells and press them onto the welding strip located on the welding heat transfer support (11) so that the back of the battery cell is in contact with the welding strip. The multiple battery cells are arranged in parallel and spaced along the extension direction of the welding strip. The welding unit (3) is located below the welding heat transfer bearing (11). The welding unit (3) is capable of reciprocating in the vertical direction to weld multiple battery cells and multiple parallel welding strips.

2. The welding apparatus for a back contact battery according to claim 1, characterized in that, The welding heat transfer bearing (11) has multiple fixing grooves extending along the conveying direction of the welding strip, and the multiple fixing grooves are spaced apart along the extension direction of the welding strip. The welding device for the back contact battery further includes: A fixing unit is disposed on the welding body (1), and the output end of the fixing unit can pass through the fixing groove and be fixedly connected to multiple parallel welding strips.

3. The welding apparatus for a back contact battery according to claim 1, characterized in that, The welding heat transfer bearing (11) is made of transparent tempered glass.

4. The welding apparatus for a back contact battery according to any one of claims 1-3, characterized in that, The welding unit (3) includes: Welding drive components; The welding component (31) is connected to the output end of the welding drive component, and the welding drive component can drive the welding component (31) to reciprocate in the vertical direction.

5. The welding apparatus for a back contact battery according to any one of claims 1-3, characterized in that, The welding device for the back contact battery also includes: A strip cutting unit (4) is provided at intervals from the welding body (1). The cell transfer unit (2) can transfer multiple welded cells and multiple parallel strips to the strip cutting unit (4). The strip cutting unit (4) is used to cut a portion of the strip between two adjacent cells to form a battery string.

6. The welding apparatus for a back contact battery according to claim 5, characterized in that, The solder strip breaking unit (4) also includes: The welding strip breaking platform has multiple breaking grooves (41) extending along the conveying direction of the welding strip, and the multiple breaking grooves (41) are arranged at intervals along the extension direction of the welding strip. Along the direction perpendicular to the battery cell, the projections of multiple parallel welding strips connected between two adjacent battery cells are located in the breaking grooves (41). A ribbon breaking assembly is provided on the ribbon breaking platform. The output end of the ribbon breaking assembly can pass through the breaking groove (41) to break part of the ribbon between two adjacent battery cells.

7. The welding apparatus for a back contact battery according to claim 6, characterized in that, The welding device for the back contact battery also includes: A collection unit is provided on the ribbon breaking platform, and the collection unit is used to collect the ribbon broken by the ribbon breaking component.

8. The welding apparatus for a back contact battery according to claim 5, characterized in that, The solder strip breaking unit (4) includes: A battery cell conveying platform is provided at an interval from the welding strip breaking platform. The battery cell transfer unit (2) is capable of transferring multiple welded battery cells and multiple parallel welding strips to the battery cell conveying platform. The battery cell conveying platform is capable of temporarily holding the multiple welded battery cells and multiple parallel welding strips.

9. The welding apparatus for a back contact battery according to any one of claims 1-3, characterized in that, The welding device for the back contact battery also includes: A visual inspection unit is electrically connected to the welding conveying unit and the welding strip conveying unit. The visual inspection unit is used to detect the position of the welding strip on the welding heat transfer support (11).

10. A method for welding a back contact battery, said welding method utilizing the welding apparatus for a back contact battery as described in any one of claims 1-9, said welding method comprising: S1: The welding strip conveying unit conveys multiple parallel welding strips connected to the busbars at opposite ends to the welding heat transfer bearing (11); S2: The welding strip fastener (12) fixes the two busbars; S3: The battery cell transfer unit (2) presses multiple battery cells onto the welding strip located on the welding heat transfer support (11), so that the back of the battery cell is in contact with the welding strip; S4: The welding unit (3) rises to weld multiple battery cells and multiple parallel welding strips.

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