Solar cell welding method

Abstract

The present invention discloses a method for welding a solar cell, including welding a strip-shaped conductive connector on one side of a cell; the method comprises the following steps: providing a bearing surface for bonding the cell on the outer surface of a welding carrier, and making the bearing surface an outwardly convex arc surface; bonding the cell on the bearing surface, and making one side surface of the strip-shaped conductive connector to be welded on the cell face outward; tightening and bonding the strip-shaped conductive connector on the outer side of the cell; and heating the strip-shaped conductive connector to weld the strip-shaped conductive connector on the cell. The present invention can simplify the welding process of the strip-shaped conductive connector and the cell, optimize the effective contact between the strip-shaped conductive connector and the cell, improve the welding performance, and improve the welding efficiency.

Description

Technical Field

[0001] The invention relates to the photovoltaic field, and in particular to a solar cell sheet welding method. Background Art

[0002] In the traditional crystalline silicon photovoltaic module manufacturing process, the cells must first be welded with welding ribbons and connected in series to form a cell string. Specifically, the method of forming a string of cells includes: placing the welding ribbons and cells alternately in sequence, with the length of the welding ribbon being approximately twice the width of the cell, so that half of the welding ribbon is on the front of a cell and the other half is on the back of the adjacent cell, and a cell string containing multiple cells and the upper and lower surfaces (i.e., positive and negative electrodes) connected in series is formed in sequence. The cell string is then transferred to the welding station through an adsorption track, and generally multiple pressing wires or pressing blocks are used to compact the upper and lower welding ribbons with the cells, and the welding ribbons are welded to the surface electrodes of the cells through infrared heating.

[0003] When welding the soldering ribbon to the battery cell, the battery cell is generally placed flat on a flat supporting surface, and the soldering ribbon is mainly pressed together with a wire mesh or a pressing block perpendicular to the direction of the soldering ribbon to bring the soldering ribbon into contact with the battery cell to complete the welding. The pressure is applied at several scattered points on the soldering ribbon, and effective contact cannot be guaranteed at the parts without pressure. In particular, when the soldering ribbon is heated, the unpressed parts of the soldering ribbon are very likely to stretch and twist, making welding impossible. In addition, a pressing wire presses multiple soldering ribbons vertically and crosswise at the same time, and the middle soldering ribbon is subjected to little force or the pressing wire is suspended in the air and no effective pressing is formed, resulting in invalid welding at this part. Therefore, the traditional welding process for welding soldering ribbons to battery cells results in many false welds.

[0004] In addition, in photovoltaic modules, triangular welding ribbons and other special-shaped welding ribbons with optical advantages are increasingly used. In traditional welding processes, it is difficult to ensure the consistency of the direction of triangular welding ribbons and other special-shaped welding ribbons through clamping, transportation, pressing, etc., and it is difficult to ensure that triangular welding ribbons and other special-shaped welding ribbons do not flip over on the entire surface of the battery cell. Therefore, the application of special-shaped welding ribbons, especially ultra-fine special-shaped welding ribbons, requires new welding methods and processes to effectively control the consistency of the orientation of the welding ribbons to achieve effective welding of special-shaped welding ribbons.

[0005] In addition, in the development of photovoltaic technology, more main grids and thinning are still important directions for the development of battery module technology. The pattern for collecting current on the surface of the battery cell is a fine grid. Considering the shading and current transmission loss, the aspect ratio of the fine grid should be as large as possible; the pattern used for connecting the battery cells in series and collecting the fine grid current is the main grid. To a certain extent, the more main grids there are, the less silver consumption of the fine grid can be, the narrower the pattern can be, and the thermal resistance loss of the fine grid is reduced, which reduces the silver consumption of the battery cell and improves the efficiency. Therefore, the main grid of the battery cell has been developing in more and more directions. In the cost of photovoltaic modules, the cost of crystalline silicon accounts for about half. The thicker the silicon wafer is, the more crystalline silicon material is used, and the higher the cost of crystalline silicon is, so the application of thin silicon wafers is also one of the important directions for the development of photovoltaic modules.

[0006] The more main grids a cell has, the more and thinner the welding ribbons are needed. The diameter of the smallest round wire welding ribbon currently used is less than 0.2mm. There are as many as 30 welding ribbons on a 210mm wide cell. Conventional welding process equipment mainly uses grippers to grab, pull, transfer, and place, and presses blocks to reduce the offset, rolling, and twisting of the welding ribbons. With so many thin welding ribbons, the control difficulty of using traditional welding processes increases sharply: 1) One welding ribbon corresponds to one reel, and the number of reels is large, which makes it difficult to design the reel position, lay out the wires, and route the wires at the same time; 2) Automation also requires supporting shortening of the flow path of welding wires and batteries, positioning of welding ribbons, and the design of the front-to-back correlation matching between various actions; 3) The impact of equipment disconnection and other failures is also greatly increased, and it is difficult to recover after a failure and to maintain the equipment.

[0007] In addition, in the development of thin silicon wafers, the thinner the silicon wafer, the greater the warping of the cell after welding, the higher the risk of desoldering, hidden cracks, and splits, and the cell warping is not conducive to subsequent stacking and lamination processes. At present, the mainstream cell thickness is about 150um. With the development of battery technology, the battery process can achieve mass production of thinner and thinner cells. Components urgently need to match the thin-sheet welding process to jointly achieve the goal of reducing the cost of component crystalline silicon. Summary of the invention

[0008] The object of the present invention is to provide a method for welding a solar cell, including welding a strip-shaped conductive connector on one side of the cell; the method comprises the following steps:

[0009] A bearing surface for bonding the battery cells is provided on the outer surface of a welding carrier, and the bearing surface is an outwardly convex arc surface (which may be a circular arc surface);

[0010] Laminating the battery cell on the carrying surface so that the battery cell does not protrude beyond the carrying surface to which it is attached, and the surface of one side of the strip-shaped conductive connector on the battery cell to be welded faces outward (that is, the surface of one side of the strip-shaped conductive connector on the battery cell to be welded faces away from the carrying surface);

[0011] The strip-shaped conductive connector is stretched and fitted on the outer side surface of the battery cell (i.e., the side surface of the battery cell opposite to the supporting surface) along the circumference of the supporting surface, so that the strip-shaped conductive connector presses the battery cell onto the supporting surface;

[0012] The strip-shaped conductive connecting member is heated to weld the strip-shaped conductive connecting member onto the battery cell.

[0013] Preferably, if a plurality of mutually parallel grid lines are provided on the outer side surface of the battery cell, when the battery cell is attached to the supporting surface, the extension direction of the grid lines on the outer side surface of the battery cell is made perpendicular to the axis of the supporting surface; and when the strip-shaped conductive connector is stretched and attached to the outer side surface of the battery cell, the strip-shaped conductive connector is attached correspondingly to the grid lines on the outer side surface of the battery cell.

[0014] Preferably, after the strip-shaped conductive connector is welded to the battery cell, the strip-shaped conductive connector is cut off to achieve a small segment of the strip-shaped conductive connector remaining on the battery cell, and the small segment of the strip-shaped conductive connector is used for series connection of the battery cell on which it is located (one end of the small segment of the strip-shaped conductive connector extends beyond the battery cell on which it is located, and the other end of the small segment of the strip-shaped conductive connector does not extend beyond the battery cell on which it is located); then the battery cell is removed from the carrying surface of the welding carrier (after the battery cell is removed, it can be turned over and the strip-shaped conductive connector can be welded to one side of the battery cell again).

[0015] Preferably, the strip-shaped conductive connectors are welded on one side of the battery cell to the front and back sides of the battery cell respectively, thereby completing the double-sided welding of the strip-shaped conductive connectors on the battery cell.

[0016] For the specific selection of the strip-shaped conductive connector, the specific implementation method of tightening the strip-shaped conductive connector to fit the outer surface of the battery cell, the specific implementation method of heating the strip-shaped conductive connector, and other related specific contents, please refer to the embodiments.

[0017] The advantages and beneficial effects of the present invention are:

[0018] The present invention can simplify the welding process of the strip-shaped conductive connecting member (welding wire or welding ribbon) and the battery cell, can optimize the effective contact between the strip-shaped conductive connecting member (welding wire or welding ribbon) and the battery cell, can improve the welding performance, and improve the welding efficiency.

[0019] The bearing surface of the welding carrier of the present invention is an outwardly convex arc surface, the battery cell is attached to the bearing surface, and the strip-shaped conductive connecting member (welding wire or welding strip) is tightly attached to the battery cell along the circumferential direction of the arc surface of the bearing surface; during welding, the battery cell and the strip-shaped conductive connecting member (welding wire or welding strip) are bent on the bearing surface along the circumferential direction of the arc surface of the bearing surface, so that the strip-shaped conductive connecting member (welding wire or welding strip) and the battery cell can be continuously and fully attached together, fully stressed, and fully in contact.

[0020] The present invention can wind multiple rows of battery sheets at one time and weld multiple rows of battery sheets at one time, thereby improving welding efficiency.

[0021] The present invention also has the following characteristics:

[0022] The present invention has less false welds; since the strip-shaped conductive connecting member (welding wire or welding strip) and the battery cell can be continuously attached and evenly stressed, welding is completed under the condition of full contact under stress, so the welding is complete and sufficient, which can greatly reduce the number of false welds.

[0023] The battery cell has less warping after welding in the present invention. Currently, the battery cell is generally placed flat on a flat supporting surface, and then a strip-shaped conductive connector (welding wire or welding strip) is laid on the battery cell and welded. Since the thermal expansion of the strip-shaped conductive connector (welding wire or welding strip) is generally greater than that of the battery cell (silicon wafer), after the welding is cooled, the cooling and contraction of the strip-shaped conductive connector (welding wire or welding strip) will cause the battery cell to curl toward the outer side (i.e., the welding surface), thereby causing the battery cell to warp. In the present invention, the supporting surface is an outwardly convex arc surface, and the bending direction of the supporting surface is exactly opposite to the curling direction of the battery cell after the welding is cooled, which just suppresses the warping of the battery cell, so that the warping amplitude of the battery cell after welding is greatly reduced.

[0024] The number of reels of the strip-shaped conductive connector (welding wire or welding strip) used in the present invention is small and easy to control; the present invention can use only one strip-shaped conductive connector to wind all the battery cells on the welding carrier, and the strip-shaped conductive connectors (welding wire or welding strip) of all the battery cells on the welding carrier are from the same reel, so the number of reels is greatly reduced, which can simplify the equipment space design, and the maintenance of the strip-shaped conductive connector (welding wire or welding strip) such as breakage and deviation and the operation of line replacement are also greatly simplified.

[0025] During the winding process of the present invention, the strip-shaped conductive connecting member (welding wire or welding strip) has less deviation; after the strip-shaped conductive connecting member (welding wire or welding strip) comes out from the reel, it can go directly to the battery cell, and be aligned with the grid line on the battery cell and tightened and fixed, which can completely eliminate the conventional actions of cutting, clamping, stretching, and transporting the strip-shaped conductive connecting member (welding wire or welding strip), and almost completely eliminates the possibility of deviation of the strip-shaped conductive connecting member (welding wire or welding strip).

[0026] The present invention can weld a large number of strip-shaped conductive connector segments (the strip-shaped conductive connector segments are used for the serial connection of the battery slices on which they are located) on a single battery slice at one time, and can weld and form hundreds of strip-shaped conductive connector segments on a single battery slice at one time. Theoretically, the final number of strip-shaped conductive connector segments on a single battery slice is equal to the number of rotations of the side circumference of the welding carrier when winding the strip-shaped conductive connector, which is easy to control and implement.

[0027] The present invention can be applied to the welding of special-shaped welding strips (such as triangular welding strips) that require direction identification; when winding the triangular welding strip, the bearing surface (the convex arc surface) can automatically correct the direction of the top angle of the triangular welding strip, so that the top angle of the triangular welding strip faces upward and the bottom surface faces downward, thereby realizing the welding of special-shaped welding strips such as triangular welding strips, and the triangular welding strip is not easy to flip over and has a high yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figures 1 to 5 It is a schematic diagram of the present invention. DETAILED DESCRIPTION

[0029] The specific implementation of the present invention is further described below in conjunction with the accompanying drawings and embodiments. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

[0030] The present invention provides a solar cell welding method, which completes the double-sided welding of the strip-shaped conductive connector on the solar cell by welding the strip-shaped conductive connector on the front and back sides of the solar cell on the single side.

[0031] The single-sided welding of the strip-shaped conductive connector of the battery cell comprises the following steps:

[0032] A supporting surface for bonding the battery cells is provided on the outer surface of a welding carrier, so that the supporting surface is an outwardly convex arc surface (which may be a circular arc surface), and the arc height of the arc surface is not greater than one quarter of the arc length;

[0033] Laminating the battery cell on the carrying surface so that the battery cell does not protrude beyond the carrying surface to which it is attached, and the surface of one side of the strip-shaped conductive connector on the battery cell to be welded faces outward (that is, the surface of one side of the strip-shaped conductive connector on the battery cell to be welded faces away from the carrying surface);

[0034] Then, the strip-shaped conductive connector is stretched and attached to the outer side surface of the battery cell (i.e., the side surface of the battery cell opposite to the supporting surface) along the circumference of the supporting surface, and then the strip-shaped conductive connector presses the battery cell onto the supporting surface;

[0035] Then, the strip-shaped conductive connector is heated by direct heating, infrared heating or hot air heating, so that the strip-shaped conductive connector is welded on the battery cell;

[0036] Then the strip-shaped conductive connector is cut off to achieve a small segment of the strip-shaped conductive connector remaining on the battery cell, and the small segment of the strip-shaped conductive connector is used for the series connection of the battery cell where it is located (one end of the small segment of the strip-shaped conductive connector exceeds the battery cell where it is located, and the other end of the small segment of the strip-shaped conductive connector does not exceed the battery cell where it is located);

[0037] Then the battery cell is removed from the carrying surface of the welding carrier (after the battery cell is removed, it can be turned over and the strip-shaped conductive connector is welded to the battery cell on one side again).

[0038] Specific:

[0039] 1) The carrying surface can be endowed with a vacuum adsorption function (for example, the carrying surface can be evenly distributed with air suction ports, and vacuum adsorption can be performed through the air suction ports); and when the battery cell is attached to the carrying surface, the battery cell is vacuum adsorbed through the carrying surface, so that the battery cell is stably adsorbed and attached to the carrying surface.

[0040] 2) The welding carrier can be provided with a heating function, and the battery cell on the carrying surface and the strip-shaped conductive connector on the outer surface of the battery cell can be heated by the welding carrier, so that the strip-shaped conductive connector is welded to the battery cell.

[0041] 3) If grid lines are provided on the outer side of the battery cell, when the battery cell is attached to the support surface, the extension direction of the grid lines on the outer side of the battery cell is perpendicular to the axis of the support surface; and when the strip-shaped conductive connector is tightly attached to the outer side of the battery cell, the strip-shaped conductive connector is attached to the grid lines on the outer side of the battery cell accordingly.

[0042] 4) The strip-shaped conductive connector can be a welding wire or a welding strip; if the strip-shaped conductive connector has a flat bottom surface for welding with the battery cell (such as the cross-sectional shape of the strip-shaped conductive connector is a triangle or a rectangle), when the strip-shaped conductive connector is stretched and attached to the outer side of the battery cell, the flat bottom surface of the strip-shaped conductive connector is directed toward the outer side of the battery cell, so that the strip-shaped conductive connector is stably attached to the outer side of the battery cell;

[0043] For example, the strip-shaped conductive connector can be a triangular welding strip; when the strip-shaped conductive connector (triangular welding strip) is stretched and fitted tightly to the outer side of the battery cell, the bottom surface of the triangular welding strip is directed toward the outer side surface of the battery cell (that is, the top angle of the triangular welding strip is opposite to the outer side surface of the battery cell), so that the strip-shaped conductive connector (triangular welding strip) is stably fitted to the outer side surface of the battery cell.

[0044] 5) If Figure 1 As shown, the strip-shaped conductive connector can be stretched and fitted to the outer surface of the battery cell by making it cross the battery cell along the circumference of the supporting surface and pulling the sections of the strip-shaped conductive connector located outside the two sides of the battery cell toward the welding carrier and / or the supporting surface.

[0045] 6) If Figures 2 to 5 As shown, the welding carrier can also be provided with a rotating shaft, and the outer surface of the welding carrier includes a side circumferential surface surrounding the rotating shaft; the bearing surface is located on the side circumferential surface of the welding carrier, and the axis of the bearing surface is parallel to or colinear with the axis of the rotating shaft; and the strip-shaped conductive connecting member is wound around the circumferential direction of the side circumferential surface of the welding carrier and tightly wrapped around the battery cell on the side circumferential surface of the welding carrier, so as to achieve the strip-shaped conductive connecting member being tightly attached to the outer surface of the battery cell;

[0046] In addition, if the axis of the rotating shaft is located on the center line of the welding carrier, when the strip-shaped conductive connector is wound along the circumferential direction of the side surface of the welding carrier and the battery sheet on the side surface of the welding carrier is tightly wound, the side surface of the welding carrier is rotated around the axis of the rotating shaft, which can facilitate the winding of the strip-shaped conductive connector;

[0047] Moreover, only one strip-shaped conductive connection piece may be used to wrap the strip-shaped conductive connection piece around the circumference of the side surface of the welding carrier and tightly wrap the battery sheet on the side surface of the welding carrier;

[0048] More preferably, multiple rows of bearing surfaces can be arranged on the side circumferential surface of the welding carrier, and each row of bearing surfaces is arranged in sequence along the circumference of the side circumferential surface of the welding carrier, and the bearing surfaces in the same row are arranged in sequence along the axial direction of the rotating shaft, and the axis center of each bearing surface is parallel or colinear with the axis center of the rotating shaft; more specifically, multiple rows of bearing surfaces can be evenly distributed along the circumference of the side circumferential surface of the welding carrier, and even each bearing surface can be evenly distributed on the side circumferential surface of the welding carrier; battery cells are respectively bonded on multiple rows of bearing surfaces so that multiple rows of battery cells can be wound at one time and multiple rows of battery cells can be welded at one time, which can improve welding efficiency.

[0049] The specific embodiments of the present invention using the winding strip conductive connecting member are as follows:

[0050] Example 1

[0051] like Figure 2 As shown, this embodiment provides a method for welding a solar cell, by welding a strip-shaped conductive connector on the front and back sides of the cell, respectively, to complete the double-sided welding of the strip-shaped conductive connector on the cell; and a plurality of grid lines parallel to each other are respectively provided on the front and back sides of the cell;

[0052] The single-sided welding of the strip-shaped conductive connector of the battery cell comprises the following steps:

[0053] A welding carrier with a rotating shaft is provided, so that the axis of the rotating shaft is located on the center line of the welding carrier, and the welding carrier has a side circumferential surface surrounding the rotating shaft; a pair of bearing surfaces for battery cells to be attached are provided on the side circumferential surface of the welding carrier, so that the pair of bearing surfaces are both convex arc surfaces (which can be circular arc surfaces), the pair of bearing surfaces are symmetrically arranged, and the axis centers of the pair of bearing surfaces are parallel or colinear with the axis center of the rotating shaft; the pair of bearing surfaces are respectively provided with a vacuum adsorption function (for example, the pair of bearing surfaces are respectively provided with exhaust ports, and vacuum adsorption can be performed through the exhaust ports); the welding carrier has a heating function that can heat the pair of bearing surfaces;

[0054] The battery cells are respectively attached to the pair of supporting surfaces so that the battery cells do not extend beyond the supporting surfaces to which they are attached, so that one side surface of the strip-shaped conductive connector to be welded on the battery cell faces outward (that is, one side surface of the strip-shaped conductive connector to be welded on the battery cell is opposite to the corresponding supporting surface), and the extension direction of the grid lines on the outer side surface of the battery cell (that is, the side surface of the battery cell opposite to the corresponding supporting surface) is perpendicular to the axis of the corresponding supporting surface (that is, perpendicular to the axis of the rotating shaft); and the battery cells on the supporting surface are vacuum-adsorbed so that the battery cells are stably adsorbed and attached to the corresponding supporting surface;

[0055] Then, the strip-shaped conductive connector is wound circumferentially along the side circumference of the welding carrier and tightly wrapped around the battery cells on the side circumference of the welding carrier, so that the strip-shaped conductive connector is tightly fitted on the outer side of each battery cell; and when winding the strip-shaped conductive connector, the strip-shaped conductive connector is made to correspond to the grid lines on the outer side of the battery cell; specifically, only one strip-shaped conductive connector can be used for winding; the strip-shaped conductive connector can be a flat welding strip, and when winding the flat welding strip, the bottom surface of the flat welding strip is made to face the outer side of the battery cell, so that the flat welding strip is stably fitted on the corresponding grid lines on the outer side of the battery cell; and when winding the strip-shaped conductive connector, the side circumference of the welding carrier is rotated around the axis of the rotating shaft, which can facilitate the winding of the strip-shaped conductive connector; more specifically, the rotating shaft can be driven to rotate around its own axis by an external mechanism (such as a motor), and the welding carrier can be driven to rotate as a whole by the rotating shaft, thereby achieving the rotation of the side circumference of the welding carrier around the axis of the rotating shaft;

[0056] Then, the strip-shaped conductive connector is heated, so that the strip-shaped conductive connector is synchronously welded on each battery cell; specifically: 1) the battery cells on each carrying surface and the strip-shaped conductive connector on the outer side of the battery cell can be heated by a welding carrier, so that the strip-shaped conductive connector is synchronously welded on each battery cell; 2) the outer side of each battery cell and the strip-shaped conductive connector on the outer side can also be heated by infrared heating (such as using linear infrared to irradiate the outer side of each battery cell and the strip-shaped conductive connector on the outer side), so that the strip-shaped conductive connector is synchronously welded on each battery cell;

[0057] Then the strip-shaped conductive connector is cut off, so that a small segment of the strip-shaped conductive connector remains on each battery cell, and the small segment of the strip-shaped conductive connector is used for connecting the battery cells where it is located (one end of the small segment of the strip-shaped conductive connector exceeds the battery cell where it is located, and the other end of the small segment of the strip-shaped conductive connector does not exceed the battery cell where it is located);

[0058] Then, each battery cell is removed from the corresponding supporting surface of the welding carrier (after the battery cell is removed, it can be turned over and the strip-shaped conductive connector can be welded to the battery cell on one side again).

[0059] Example 2

[0060] like Figure 3 As shown, this embodiment provides a method for welding a solar cell, by welding a strip-shaped conductive connector on the front and back sides of the cell, respectively, to complete the double-sided welding of the strip-shaped conductive connector on the cell; and a plurality of grid lines parallel to each other are respectively provided on the front and back sides of the cell;

[0061] The single-sided welding of the strip-shaped conductive connector of the battery cell comprises the following steps:

[0062] A welding carrier with a rotating shaft is provided, and the axis of the rotating shaft is located on the center line of the welding carrier; the welding carrier has a side circumferential surface surrounding the rotating shaft, and the side circumferential surface of the welding carrier is surrounded by a plurality of bearing surfaces for battery cells to be attached (the main body of the welding carrier may be a prism coaxial with the rotating shaft); the plurality of bearing surfaces are all convex arc surfaces (may be circular arc surfaces), and the axis of the plurality of bearing surfaces are parallel to or colinear with the axis of the rotating shaft; the plurality of bearing surfaces are respectively provided with a vacuum adsorption function (for example, the plurality of bearing surfaces are respectively provided with exhaust ports, and vacuum adsorption can be performed through the exhaust ports); the welding carrier has a heating function that can heat the plurality of bearing surfaces;

[0063] The battery cells are respectively attached to the multiple carrying surfaces so that the battery cells do not extend beyond the carrying surfaces to which they are attached, so that one side surface of the strip-shaped conductive connector to be welded on the battery cell faces outward (that is, one side surface of the strip-shaped conductive connector to be welded on the battery cell is opposite to the corresponding carrying surface), and the extension direction of the grid lines on the outer side surface of the battery cell (that is, the side surface of the battery cell opposite to the corresponding carrying surface) is perpendicular to the axis of the corresponding carrying surface (that is, perpendicular to the axis of the rotating shaft); and the battery cell on the carrying surface is vacuum-adsorbed so that the battery cell is stably adsorbed and attached to the corresponding carrying surface;

[0064] Then, the strip-shaped conductive connector is wound around the circumferential direction of the side surface of the welding carrier and the battery cells on the side surface of the welding carrier are tightly wound, so that the strip-shaped conductive connector is tightly fitted on the outer side surface of each battery cell; and when winding the strip-shaped conductive connector, the strip-shaped conductive connector is correspondingly fitted with the grid lines on the outer side surface of the battery cell; specifically, only one strip-shaped conductive connector can be used for winding; the strip-shaped conductive connector can be a round wire welding strip; and when winding the strip-shaped conductive connector, the side surface of the welding carrier is rotated around the axis of the rotating shaft, which can facilitate the winding of the strip-shaped conductive connector; more specifically, the rotating shaft can be driven to rotate around its own axis by an external mechanism (such as a motor), and the welding carrier is driven to rotate as a whole by the rotating shaft, thereby realizing the rotation of the side surface of the welding carrier around the axis of the rotating shaft;

[0065] Then, the strip-shaped conductive connector is heated, so that the strip-shaped conductive connector is synchronously welded on each battery cell; specifically: 1) the battery cells on each carrying surface and the strip-shaped conductive connector on the outer side of the battery cell can be heated by a welding carrier, so that the strip-shaped conductive connector is synchronously welded on each battery cell; 2) the outer side of each battery cell and the strip-shaped conductive connector on the outer side can also be heated by hot air heating (such as using hot air to blow the outer side of each battery cell and the strip-shaped conductive connector on the outer side), so that the strip-shaped conductive connector is synchronously welded on each battery cell;

[0066] Then the strip-shaped conductive connector is cut off, so that a small segment of the strip-shaped conductive connector remains on each battery cell, and the small segment of the strip-shaped conductive connector is used for connecting the battery cells where it is located (one end of the small segment of the strip-shaped conductive connector exceeds the battery cell where it is located, and the other end of the small segment of the strip-shaped conductive connector does not exceed the battery cell where it is located);

[0067] Then, each battery cell is removed from the corresponding supporting surface of the welding carrier (after the battery cell is removed, it can be turned over and the strip-shaped conductive connector can be welded to the battery cell on one side again).

[0068] Example 3

[0069] like Figure 4 As shown, this embodiment provides a method for welding a solar cell, by welding a strip-shaped conductive connector on the front and back sides of the cell, respectively, to complete the double-sided welding of the strip-shaped conductive connector on the cell; and a plurality of grid lines parallel to each other are respectively provided on the front and back sides of the cell;

[0070] The single-sided welding of the strip-shaped conductive connector of the battery cell comprises the following steps:

[0071] A welding carrier with a rotating shaft is provided, and the axis of the rotating shaft is located on the center line of the welding carrier; the welding carrier has a side circumferential surface surrounding the rotating shaft, and the side circumferential surface of the welding carrier is a circumferential surface coaxial with the rotating shaft (the main body of the welding carrier can be a cylinder coaxial with the rotating shaft); a plurality of arc surface areas are divided on the side circumferential surface of the welding carrier and are sequentially spaced along the circumference of the side circumferential surface, and the plurality of arc surface areas are evenly distributed along the circumference of the side circumferential surface of the welding carrier; each arc surface area is a bearing surface for battery cells to be attached; each bearing surface has a vacuum adsorption function (for example, each bearing surface is evenly distributed with an exhaust port, and vacuum adsorption can be performed through the exhaust port); the welding carrier has a heating function that can heat each bearing surface;

[0072] The battery cells are respectively attached to each carrying surface so that the battery cells do not extend beyond the carrying surface to which they are attached, so that one side surface of the strip-shaped conductive connector to be welded on the battery cell faces outward (that is, one side surface of the strip-shaped conductive connector to be welded on the battery cell is opposite to the corresponding carrying surface), and the extension direction of the grid lines on the outer side surface of the battery cell (that is, the side surface of the battery cell opposite to the corresponding carrying surface) is perpendicular to the axis of the corresponding carrying surface (that is, perpendicular to the axis of the rotating shaft); and the battery cells on the carrying surface are vacuum-adsorbed so that the battery cells are stably adsorbed and attached to the corresponding carrying surface;

[0073] Then, the strip-shaped conductive connector is wound around the circumferential surface of the welding carrier and the battery cells on the circumferential surface of the welding carrier are tightly wound, so that the strip-shaped conductive connector is tightly fitted on the outer side of each battery cell; and when the strip-shaped conductive connector is wound, the strip-shaped conductive connector is correspondingly fitted with the grid lines on the outer side of the battery cell; specifically, only one strip-shaped conductive connector can be used for winding; the strip-shaped conductive connector can be a triangular welding strip, and when the triangular welding strip is wound, the bottom surface of the triangular welding strip is facing the outer side of the battery cell (that is, the top angle of the triangular welding strip is opposite to the outer side of the battery cell), so that the triangular welding strip is stably fitted on the outer side of the battery cell corresponding grid line; and in the process of winding the triangular welding strip, the state in which the bottom surface of the triangular welding strip is attached to the outer side surface of the battery cell is the most stable, so the triangular welding strip can automatically correct the direction of the top angle during the winding process, so that the top angle faces upward and the bottom surface faces downward, so as to achieve stable attachment to the outer side surface of the battery cell; and when winding the strip-shaped conductive connector, the side circumference of the welding carrier is rotated around the axis of the rotating shaft, which can facilitate the winding of the strip-shaped conductive connector; more specifically, the rotating shaft can be driven to rotate around its own axis by an external mechanism (such as a motor), and the welding carrier can be driven to rotate as a whole by the rotating shaft, thereby achieving the rotation of the side circumference of the welding carrier around the axis of the rotating shaft;

[0074] Then, the strip-shaped conductive connector is heated, so that the strip-shaped conductive connector is synchronously welded on each battery cell; specifically: 1) the battery cells on each carrying surface and the strip-shaped conductive connector on the outer side of the battery cell can be heated by a welding carrier, so that the strip-shaped conductive connector is synchronously welded on each battery cell; 2) the outer side of each battery cell and the strip-shaped conductive connector on the outer side can also be heated by hot air heating (such as using hot air to blow the outer side of each battery cell and the strip-shaped conductive connector on the outer side), so that the strip-shaped conductive connector is synchronously welded on each battery cell;

[0075] Then the strip-shaped conductive connector is cut off, so that a small segment of the strip-shaped conductive connector remains on each battery cell, and the small segment of the strip-shaped conductive connector is used for connecting the battery cells where it is located (one end of the small segment of the strip-shaped conductive connector exceeds the battery cell where it is located, and the other end of the small segment of the strip-shaped conductive connector does not exceed the battery cell where it is located);

[0076] Then, each battery cell is removed from the corresponding supporting surface of the welding carrier (after the battery cell is removed, it can be turned over and the strip-shaped conductive connector can be welded to the battery cell on one side again).

[0077] Example 4

[0078] like Figure 5As shown, this embodiment provides a method for welding a solar cell, by welding a strip-shaped conductive connector on the front and back sides of the cell, respectively, to complete the double-sided welding of the strip-shaped conductive connector on the cell; and a plurality of grid lines parallel to each other are respectively provided on the front and back sides of the cell;

[0079] The single-sided welding of the strip-shaped conductive connector of the battery cell comprises the following steps:

[0080] A welding carrier with a rotating shaft is provided, so that the axis of the rotating shaft is located on the center line of the welding carrier; the welding carrier has a side circumferential surface surrounding the rotating shaft, and the side circumferential surface of the welding carrier is a circumferential surface coaxial with the rotating shaft (the main body of the welding carrier can be a cylinder coaxial with the rotating shaft); a plurality of rows of arc surface areas are divided on the side circumferential surface of the welding carrier, so that the arc surface areas of each row are arranged in sequence along the circumferential direction of the side circumferential surface of the welding carrier, and the arc surface areas of the same row are arranged in sequence along the axial direction of the rotating shaft; each arc surface area is a bearing surface for battery cells to be attached; each bearing surface has a vacuum adsorption function (for example, each bearing surface is evenly distributed with exhaust ports, and vacuum adsorption can be performed through the exhaust ports); the welding carrier has a heating function that can heat each bearing surface;

[0081] The battery cells are respectively attached to each carrying surface so that the battery cells do not extend beyond the carrying surface to which they are attached, so that one side surface of the strip-shaped conductive connector to be welded on the battery cell faces outward (that is, one side surface of the strip-shaped conductive connector to be welded on the battery cell is opposite to the corresponding carrying surface), and the extension direction of the grid lines on the outer side surface of the battery cell (that is, the side surface of the battery cell opposite to the corresponding carrying surface) is perpendicular to the axis of the corresponding carrying surface (that is, perpendicular to the axis of the rotating shaft); and the battery cells on the carrying surface are vacuum-adsorbed so that the battery cells are stably adsorbed and attached to the corresponding carrying surface;

[0082] Then, the strip-shaped conductive connector is wound around the circumferential surface of the welding carrier and the battery cells on the circumferential surface of the welding carrier are tightly wound, so that the strip-shaped conductive connector is tightly fitted on the outer side of each battery cell; and when the strip-shaped conductive connector is wound, the strip-shaped conductive connector is correspondingly fitted with the grid lines on the outer side of the battery cell; specifically, only one strip-shaped conductive connector can be used for winding; the strip-shaped conductive connector can be a triangular welding strip, and when the triangular welding strip is wound, the bottom surface of the triangular welding strip is facing the outer side of the battery cell (that is, the top angle of the triangular welding strip is opposite to the outer side of the battery cell), so that the triangular welding strip is stably fitted on the outer side of the battery cell corresponding grid line; and in the process of winding the triangular welding strip, the state in which the bottom surface of the triangular welding strip is attached to the outer side surface of the battery cell is the most stable, so the triangular welding strip can automatically correct the direction of the top angle during the winding process, so that the top angle faces upward and the bottom surface faces downward, so as to achieve stable attachment to the outer side surface of the battery cell; and when winding the strip-shaped conductive connector, the side circumference of the welding carrier is rotated around the axis of the rotating shaft, which can facilitate the winding of the strip-shaped conductive connector; more specifically, the rotating shaft can be driven to rotate around its own axis by an external mechanism (such as a motor), and the welding carrier can be driven to rotate as a whole by the rotating shaft, thereby achieving the rotation of the side circumference of the welding carrier around the axis of the rotating shaft;

[0083] Then, the strip-shaped conductive connector is heated, so that the strip-shaped conductive connector is synchronously welded on each battery cell; specifically: 1) the battery cells on each carrying surface and the strip-shaped conductive connector on the outer side of the battery cell can be heated by a welding carrier, so that the strip-shaped conductive connector is synchronously welded on each battery cell; 2) the outer side of each battery cell and the strip-shaped conductive connector on the outer side can also be heated by infrared heating (such as using linear infrared to irradiate the outer side of each battery cell and the strip-shaped conductive connector on the outer side), so that the strip-shaped conductive connector is synchronously welded on each battery cell;

[0084] Then the strip-shaped conductive connector is cut off, so that a small segment of the strip-shaped conductive connector remains on each battery cell, and the small segment of the strip-shaped conductive connector is used for connecting the battery cells where it is located (one end of the small segment of the strip-shaped conductive connector exceeds the battery cell where it is located, and the other end of the small segment of the strip-shaped conductive connector does not exceed the battery cell where it is located);

[0085] Then, each battery cell is removed from the corresponding supporting surface of the welding carrier (after the battery cell is removed, it can be turned over and the strip-shaped conductive connector can be welded to the battery cell on one side again).

[0086] Embodiment 4 can wind multiple rows of battery cells at one time and weld multiple rows of battery cells at one time, which can improve welding efficiency.

[0087] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for welding a solar cell, comprising welding a strip-shaped conductive connector on one side of the cell; characterized in that: The single-sided welding of the strip-shaped conductive connector of the battery cell comprises the following steps: A carrying surface for bonding the battery sheet is provided on the outer surface of a welding carrier, and the carrying surface is an outwardly convex arc surface; the welding carrier is provided with a rotating shaft, and the outer surface of the welding carrier includes a side circumferential surface surrounding the rotating shaft; the carrying surface is located on the side circumferential surface of the welding carrier, and the axis of the carrying surface is parallel or colinear with the axis of the rotating shaft; Laminating the battery cell on the supporting surface, with one side of the battery cell on which the strip-shaped conductive connector to be welded faces outward; The strip-shaped conductive connector is wound around the circumference of the side surface of the welding carrier and tightly wrapped around the battery cell on the side surface of the welding carrier, so that the strip-shaped conductive connector is tightly attached to the outer surface of the battery cell; The strip-shaped conductive connecting member is heated to weld the strip-shaped conductive connecting member onto the battery cell.

2. The solar cell welding method according to claim 1, characterized in that: The outer side surface of the battery cell is provided with a plurality of grid lines parallel to each other; When the battery cell is attached to the carrier surface, the extending direction of the grid lines on the outer side of the battery cell is perpendicular to the axis of the carrier surface; When the strip-shaped conductive connecting member is stretched and tightly fitted on the outer side of the battery cell, the strip-shaped conductive connecting member is correspondingly fitted with the grid lines on the outer side of the battery cell.

3. The solar cell welding method according to claim 1, characterized in that: Make sure the axis of the rotating shaft is located on the center line of the welding carrier.

4. The solar cell welding method according to claim 1, characterized in that: When the strip-shaped conductive connector is wound around the circumferential direction of the side surface of the welding carrier and the battery sheet on the side surface of the welding carrier is tightly wound, the side surface of the welding carrier is rotated around the axis of the rotating shaft.

5. The solar cell welding method according to claim 1, characterized in that: At least two bearing surfaces are arranged on the side circumference of the welding carrier, and the axis of each bearing surface is parallel or colinear with the axis of the rotating shaft; Laminating the battery cells on each of the supporting surfaces respectively, with one side of the surface of the battery cell on which the strip-shaped conductive connector to be welded faces outward; The strip-shaped conductive connector is wound around the circumference of the side surface of the welding carrier and tightly wrapped around the battery cells on the side surface of the welding carrier, so that the strip-shaped conductive connector is tightly attached to the outer surface of each battery cell; The strip-shaped conductive connecting members are heated to be welded on each battery cell.

6. The solar cell welding method according to claim 5, characterized in that: A plurality of bearing surfaces are arranged on the side circumferential surface of the welding carrier, and the bearing surfaces are arranged in sequence along the circumferential direction of the side circumferential surface of the welding carrier.

7. The solar cell welding method according to claim 6, characterized in that: Make each bearing surface evenly distributed along the circumferential direction of the side surface of the welding carrier.

8. The solar cell welding method according to claim 5, characterized in that: Multiple rows of bearing surfaces are arranged on the side circumference of the welding carrier, so that each row of bearing surfaces is arranged in sequence along the circumference of the side circumference of the welding carrier, and the bearing surfaces in the same row are arranged in sequence along the axial direction of the rotating shaft, and the axis of each bearing surface is parallel or collinear with the axis of the rotating shaft.

9. The solar cell welding method according to claim 8, characterized in that: The multiple rows of bearing surfaces are evenly distributed along the circumferential direction of the side surface of the welding carrier.

10. The solar cell welding method according to claim 9, characterized in that: Make sure that each bearing surface is evenly distributed on the side circumference of the welding carrier.

11. The solar cell welding method according to claim 5, characterized in that: The side circumference of the welding carrier is surrounded by a plurality of bearing surfaces.

12. The solar cell welding method according to claim 11, characterized in that: Make the side surface of the welding carrier coaxial with the rotating shaft.

13. The solar cell welding method according to claim 5, characterized in that: The side circumference of the welding carrier is made into a circumferential surface coaxial with the rotating shaft.

14. The solar cell welding method according to claim 1, characterized in that: Only one strip-shaped conductive connecting member is used to make the strip-shaped conductive connecting member circumferentially wind along the side circumference of the welding carrier and tightly wind the battery sheet on the side circumference of the welding carrier.

15. The solar cell welding method according to claim 1, characterized in that: The strip-shaped conductive connecting piece is a welding wire or a welding strip.

16. The solar cell welding method according to claim 1, characterized in that: The strip-shaped conductive connecting member has a flat bottom surface for welding with the battery cell; When the strip-shaped conductive connecting member is stretched and fitted tightly on the outer side of the battery cell, the flat bottom surface of the strip-shaped conductive connecting member faces the outer side surface of the battery cell.

17. The solar cell welding method according to claim 1, characterized in that: The strip-shaped conductive connecting piece is heated by direct heating, infrared heating or hot air heating.

18. The solar cell welding method according to claim 17, characterized in that: The welding carrier is provided with a heating function, and the battery cell on the carrying surface and the strip-shaped conductive connecting members on the outer surface of the battery cell are heated by the welding carrier.

19. The solar cell welding method according to claim 1, characterized in that: The carrying surface is provided with a vacuum adsorption function; when the battery cell is attached to the carrying surface, the battery cell is vacuum adsorbed.

20. The solar cell welding method according to claim 1, characterized in that: After the strip-shaped conductive connector is welded on the battery cell, the strip-shaped conductive connector is cut off to leave a small section of the strip-shaped conductive connector on the battery cell, and the small section of the strip-shaped conductive connector is used for connecting the battery cell in series; then the battery cell is removed from the carrying surface of the welding carrier.

21. The solar cell welding method according to claim 20, characterized in that: The strip-shaped conductive connectors are welded on one side of the battery cell and on the back side of the battery cell respectively, so as to complete the double-sided welding of the strip-shaped conductive connectors on the battery cell.

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