Solar cell module

Abstract

The utility model discloses a solar cell module, and relates to the technical field of photovoltaic cells, the solar cell module comprises a welding strip, the welding strip is applied to welding of cell pieces, the welding strip is linear, the welding strip is provided with a plurality of protruding parts, the protruding parts are arranged on the welding strip at intervals, the arrangement path of the protruding parts is consistent with the extension path of the welding strip, and the extension path of the welding strip is consistent with the extension path of the welding strip. The distance between every two adjacent protruding parts is equal to the distance between every two adjacent welding points on the battery piece. According to the solder strip and the solar cell module provided by the invention, the photoelectric conversion efficiency and the current collection efficiency of the solar cell module can be improved.

Description

Technical Field

[0001] The present application relates to the field of photovoltaic cell technology, and in particular to a solar cell module. Background Art

[0002] Solar cell modules are composed of cells or cell slices of different specifications. Since the current and voltage of a single cell are very small, multiple cells need to be connected in series to obtain high voltage, then in parallel to obtain high current, and finally output through a junction box. The presence of grid lines and welding strips on the surface of the cell will block the light-receiving surface of the cell, resulting in reduced power generation efficiency of the cell; at the same time, grid lines have extremely high requirements for conductivity. In the prior art, silver paste is generally used to make grid lines. The cost of silver paste is relatively high compared to other conductive materials, resulting in high costs for cells and solar cell modules.

[0003] Busbar-free (0BB) technology refers to reducing the width of the busbar of the cell or even directly eliminating the busbar, while retaining only the thin grid or no thin grid. When the busbar width is reduced by busbar-free technology, the busbar width is reduced from hundreds of microns to tens of microns. Reducing the width of the busbar or eliminating the busbar by busbar-free (0BB) technology can reduce the amount of silver paste used and reduce component costs.

[0004] There are three main methods of 0BB technology at present, SmartWire, glue dispensing and welding glue dispensing. Among them, the specific process steps of the welding glue dispensing method include: first welding the solder ribbon to the battery cell, then glue dispensing to reinforce the connection between the solder ribbon and the battery cell, and finally laminating and alloying multiple battery cells. That is, the welding glue dispensing method uses welding to achieve preliminary fixation, and glue dispensing for further fixation. The welding glue dispensing method can increase the bonding strength between the solder ribbon and the battery cell, and is a method that is easy to operate and implement, but when the glue solidifies and shrinks, the solder ribbon is easy to pull off the fine grid, reducing the current collection efficiency of the solar cell module. Utility Model Content

[0005] The purpose of the present application is to provide a solar cell module, which can improve the photoelectric conversion efficiency and current collection efficiency of the solar cell module.

[0006] A solar cell assembly provided in an embodiment of the present application includes a cell sheet, wherein the cell sheet includes a grid line structure arranged on two sides of the cell sheet, wherein the grid line structure includes at least a plurality of first grid lines arranged along a first direction, and the first grid lines extend along a second direction;

[0007] The solar cell assembly further includes a welding strip for welding the cell sheet, the welding strip is linear and extends along a first direction, the welding strip has a plurality of protrusions, the plurality of protrusions are arranged at intervals on the welding strip, the arrangement path of the plurality of protrusions is consistent with the extension path of the welding strip, the spacing between two adjacent protrusions is equal to the spacing between adjacent welding points on the cell sheet, the welding strip extends along the first direction, and the protrusions are respectively connected to the first grid lines, and the first direction is perpendicular to the second direction;

[0008] The gate line structure further includes a plurality of second gate lines arranged along a second direction, wherein the plurality of second gate lines extend along the first direction and cross-connect with the first gate lines to form connection points;

[0009] The number of connection points on one of the second gate lines is not less than the number of the protrusions on the corresponding welding strip, and the distance between two adjacent protrusions is an integer multiple of the distance between two adjacent connection points.

[0010] As an practicable manner, the maximum dimension of the cross section of the welding strip is between 0.15-0.2 mm, and the maximum dimension of the cross section of the protrusion is between 0.2-0.8 mm.

[0011] As an practicable manner, along the extension direction of the welding strip, the cross-section of the protrusion has a shape selected from the group consisting of a square, a rectangle, a trapezoid, a circle, a semicircle and a rhombus.

[0012] As an practicable manner, along the extending direction of the welding strip, the cross-sectional area of ​​the protrusion is the same, or the cross-sectional area of ​​the protrusion first gradually increases and then gradually decreases.

[0013] As an implementable manner, the protrusion has a flat surface parallel to the central axis of the welding strip, there are two flat surfaces and they are symmetrical about the central axis of the welding strip, and the distance between the two flat surfaces is consistent with the diameter of the welding strip.

[0014] As an practicable manner, the soldering strip includes a copper substrate and an aluminum coating layer or a silver coating layer wrapped around the outer periphery of the copper substrate, and the protruding portion is a tin structure.

[0015] As an implementable manner, the welding strips include a plurality of strips, and the plurality of welding strips are respectively arranged on the second gate lines, wherein the width of the second gate lines is between 30-60 μm.

[0016] As an practicable manner, the width of the first gate line is between 30-60 μm.

[0017] As an implementable manner, the number of welding points between a second grid line and a corresponding welding strip is between 6 and 12.

[0018] As an implementable manner, the gate line structure and the welding strip are connected by welding, and the welding temperature of the welding connection is between 130° C. and 160° C.

[0019] The beneficial effects of the embodiments of the present application include:

[0020] The soldering strip in the solar cell module provided by the present application is linear, and has a plurality of protrusions on the soldering strip, and the plurality of protrusions are arranged at intervals on the soldering strip, and the protrusions have a larger cross-sectional area relative to the soldering strip, and when the soldering strip is connected to the grid line structure of the battery cell, the protrusions are connected to the welding points in correspondence, so that the contact area between the protrusions and the welding points is increased, the bonding strength between the soldering strip and the battery cell is improved, and the current collection effect is improved. The protrusions of the present application are welded in correspondence with the welding points of the grid line structure, which ensures the bonding strength between the soldering strip and the battery cell, avoids the use of glue, thereby avoiding the glue shrinkage and breaking the fine grid, and improving the current collection efficiency of the solar cell module.

[0021] In addition, compared with SmartWire, the welding method does not use a composite film, thereby avoiding the composite film from blocking the cell, thereby increasing the area of ​​the cell receiving light, thereby improving the photoelectric conversion efficiency of the solar cell module; specifically, the solar cell module of the present application has a photoelectric conversion efficiency that is 1%-5% higher than that of the prior art. Therefore, the embodiment of the present application can improve the bonding strength between the welding ribbon and the cell while improving the photoelectric conversion efficiency of the solar cell module. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 A schematic diagram of the structure of a solar cell assembly provided in an embodiment of the present application;

[0024] Figure 2 for Figure 1 Cross-section along AA;

[0025] Figure 3 for Figure 2 The enlarged view of point B in the middle;

[0026] Figure 4 for Figure 1 The cross-section in C;

[0027] Figure 5 One of the structural schematic diagrams of the welding strip provided in the embodiment of the present application;

[0028] Figure 6 The second structural schematic diagram of the welding strip provided in the embodiment of the present application;

[0029] Figure 7 The third structural schematic diagram of the welding strip provided in the embodiment of the present application;

[0030] Figure 8 This is the fourth structural schematic diagram of the welding strip provided in the embodiment of the present application.

[0031] Icons: 10 - solar cell module; 11 - cell; 12 - grid line structure; 121 - first grid line; 122 - second grid line; 123 - connection point; 124 - welding point; 13 - welding strip; 131 - protrusion. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments.

[0033] As the first generation of cells, silicon-based solar cells are still the solar cells with the highest production and installation volume in the world. At present, in the production of silicon-based solar cells, thinner solder strips are usually used to reduce the shading area, which makes the contact area between the solder strip and the grid structure welding point smaller, and the bonding force between the solder strip and the cell is weaker.

[0034] The embodiment of the present application provides a welding strip 13, which is used for welding a battery cell 11. The welding strip 13 is linear and has a plurality of protrusions 131. The plurality of protrusions 131 are arranged at intervals on the welding strip 13. The arrangement path of the plurality of protrusions 131 is consistent with the extension path of the welding strip 13. The spacing between two adjacent protrusions 131 is equal to the spacing between adjacent welding points 124 on the battery cell 11.

[0035] The welding strip 13 provided in the embodiment of the present application is applied to the welding of the battery cell 11. Specifically, the grid line structure 12 is arranged on both sides of the battery cell 11, and the welding strip 13 is arranged on the side of the grid line structure 12 away from the battery cell 11 to form a solar cell module 10. When the solar cell module 10 is working, light is irradiated to the surface of the battery cell 11 through the gap of the grid line structure 12, and the battery cell 11 receives the light and converts the light energy carried by the light into electrical energy, wherein electrons with negative charge move toward one side of the battery cell 11, are transmitted to the welding strip 13 through the grid line structure 12 on one side, and are then collected through the welding strip 13; holes with positive charge move toward the other side of the battery cell 11, are transmitted to the welding strip 13 through the grid line structure 12 on the other side, and are then collected through the welding strip 13, thereby realizing the conversion of light energy.

[0036] Among them, the welding strip 13 is linear, and has multiple protrusions 131 on the welding strip 13. The protrusions 131 are respectively connected to the welding points 124 of the gate line structure 12 one by one. Because the protrusions 131 have a larger cross-sectional area, the connection strength between the protrusions 131 and the welding points 124 can be increased, thereby increasing the bonding strength between the welding strip 13 and the battery cell 11.

[0037] Since the soldering ribbon 13 is provided with a protrusion 131 for one-to-one connection with the soldering point 124, the soldering ribbon 13 can be set to be thinner, so that the projection area of ​​the soldering ribbon 13 on the battery cell 11 is smaller, so that the exposed area of ​​the battery cell 11 is larger, and the area of ​​the battery cell 11 receiving light is increased. In addition, compared with SmartWire, the welding method does not use a composite film, thereby avoiding the shielding of the battery cell 11 by the composite film, thereby further increasing the area of ​​the battery cell 11 receiving light, thereby improving the photoelectric conversion efficiency of the solar cell module 10. It should be noted that the protrusion 131 has a larger cross-sectional area than the soldering ribbon 13, but the soldering ribbon 13 is thinner, which can reduce the light-blocking area of ​​the soldering ribbon 13 compared with the prior art, thereby increasing the area of ​​the battery cell 11 receiving light.

[0038] In addition, since the protrusion 131 has a larger cross-sectional area relative to the welding strip 13, according to the calculation formula of resistance, the larger the cross-sectional area, the smaller the resistance, that is, the protrusion 131 can reduce the resistance of the welding strip 13. Smaller resistance means less resistance to current, thereby reducing the loss of electrons transmitted by the welding strip 13.

[0039] The welding strip 13 provided in the embodiment of the present application is applied to the welding of the battery cell 11. The welding strip 13 is linear and has a plurality of protrusions 131 on the welding strip 13. The plurality of protrusions 131 are arranged at intervals on the welding strip 13. The protrusions 131 have a larger cross-sectional area than the welding strip 13. When the welding strip 13 is connected to the grid line structure 12 of the battery cell 11, the protrusions 131 are connected to the welding points 124 in a corresponding manner, so that the contact area between the protrusions 131 and the welding points 124 is increased, the bonding force between the welding strip 13 and the battery cell 11 is improved, and the current collection effect is improved. The corresponding welding of the protrusions 131 and the welding points 124 of the present application avoids the use of glue, thereby avoiding the glue from shrinking and breaking the fine grid, and improving the current collection efficiency of the solar cell module 10.

[0040] Optional, such as Figure 1 As shown, the maximum dimension of the cross section of the welding strip 13 is between 0.15-0.2 mm, and the maximum dimension of the cross section of the protrusion 131 is between 0.2-0.8 mm.

[0041] The maximum size of the cross section of the welding ribbon 13 is between 0.15-0.2 mm. Compared with the welding ribbon 13 with a diameter of 0.25 mm in the prior art, the diameter of the welding ribbon 13 in the embodiment of the present application is reduced, thereby reducing the projection area of ​​the welding ribbon 13 on the battery cell 11, thereby increasing the exposed area of ​​the battery cell 11. When the solar cell module 10 is working, when the exposed area of ​​the battery cell 11 increases, the area receiving light increases, thereby improving the photoelectric conversion efficiency of the solar cell module 10. In addition, the cross section area of ​​the welding ribbon 13 is small, which can also reduce the amount of conductive material used in the welding ribbon 13 and reduce the cost of the welding ribbon 13. For example, the maximum size of the cross section of the welding ribbon 13 can be 0.15 mm, 0.18 mm, and 0.2 mm.

[0042] The maximum size of the cross section of the protrusion 131 is set between 0.2-0.8 mm, so that the area of ​​the protrusion 131 is increased. For example, the maximum size of the cross section of the protrusion 131 can be 0.2 mm, 0.4 mm, 0.6 mm and 0.8 mm.

[0043] In one possible implementation of the embodiment of the present application, Figure 5 , Figure 6 , Figure 7 and Figure 8 As shown, along the extension direction of the welding strip 13 , the cross-section of the protrusion 131 is in the shape of a square, a rectangle, a trapezoid, a circle, a semicircle, and a rhombus.

[0044] The shape of the protrusion 131 along the extension direction of the solder strip 13 is one of square, rectangle, trapezoid, circle, semicircle and rhombus, so that the protrusion 131 has more shapes, which is more conducive to the production of the solder strip 13.

[0045] When the cross-section of the protrusion 131 is in the shape of a square, a rectangle or a circle, the protrusion 131 occupies a wider width and can be connected to the welding point 124 in a wider range. When the positions of the welding point 124 and the protrusion 131 deviate, the protrusion 131 can still achieve welding point 124 with the welding point 124, thereby reducing the accuracy of the position alignment of the protrusion 131 and the welding point 124; when the cross-section of the protrusion 131 is in the shape of a circle, a semicircle or a diamond, the center of the protrusion 131 corresponds to the welding point 124. When the protrusion 131 is connected to the welding point 124, the protrusion 131 melts so that more conductive material is connected to the welding point 124, thereby improving the connection strength between the welding point 124 and the protrusion 131.

[0046] A person skilled in the art may select a specific cross-sectional shape of the protrusion 131 according to actual conditions, as long as the cross-sectional area of ​​the protrusion 131 can be increased.

[0047] Specifically, Figure 6 As shown, the protrusion 131 is circular along the extension direction of the welding strip 13, that is, the protrusion 131 is a circular ring structure, the circular ring structure is sleeved on the welding strip 13, and the central axis of the circular ring structure coincides with the central axis of the welding strip 13. The circular ring structure is easy to prepare, and the contact part between the protrusion 131 and the welding point 124 of the battery cell 11 is an arc surface, which can make the protrusion 131 fully contact with the electrode when melting, reduce the risk of cold welding, and help improve welding quality and welding stability. It can effectively solve the problem of cold welding and poor welding stability of the welding strip 13 in the prior art.

[0048] like Figure 7 As shown, the protrusion 131 is semicircular along the extension direction of the welding strip 13, that is, the protrusion 131 is a semi-annular structure. Figure 6 Only a part of it is protruding; the semi-annular structure is arranged on the welding belt 13, and the central axis of the semi-annular structure coincides with the central axis of the welding belt 13.

[0049] In addition, the protrusion 131 may also be a U-shaped structure, and both ends of the U-shaped structure are flush with the surface of the welding strip 13. In other words, the protrusion 131 of the U-shaped structure may be sleeved on the surface of the welding strip 13.

[0050] As an practicable manner, along the extending direction of the welding strip 13 , the cross-sectional area of ​​the protrusion 131 is the same, or the cross-sectional area of ​​the protrusion 131 gradually increases and then gradually decreases.

[0051] Specifically, such as 6 and Figure 7 As shown, the cross-sectional area of ​​the protrusion 131 along the extension direction of the welding strip 13 is the same. Figure 5 and Figure 8 As shown, the cross-sectional area of ​​the protrusion 131 gradually increases and then gradually decreases. Figure 5 The cross-sectional area of ​​the protrusion 131 along the extension direction of the welding strip 13 is rectangular, and gradually increases and then gradually decreases, so that the protrusion 131 is formed by two pyramidal structures connected relatively, and the central axis of the two pyramidal structures coincides with the central axis of the welding strip 13. The embodiment of the present application is more conducive to the traction of the welding strip 13 through the above-mentioned arrangement, and avoids the breaking of the welding strip 13. Therefore, the embodiment of the present application can greatly improve the structural stability of the welding strip 13 and the safety during welding and pulling. In addition, the embodiment of the present application can further reduce the shading area, and by ensuring that the welding strip 13 and the welding point 124 have a larger contact surface, the light receiving area of ​​the battery cell 11 is ensured, while increasing the photoelectric conversion efficiency of the solar cell module 10.

[0052] Figure 8The cross-sectional area of ​​the protrusion 131 along the extension direction of the welding strip 13 is circular, and gradually increases and then gradually decreases, so that the protrusion 131 is formed by two conical structures connected relatively. The above-mentioned arrangement of the embodiment of the present application is more conducive to the pulling of the welding strip 13 and avoids the breaking of the welding strip 13. Therefore, the embodiment of the present application can greatly improve the structural stability of the welding strip 13 and the safety during welding and pulling.

[0053] Optional, such as Figure 5 As shown, the protrusion 131 has a flat surface parallel to the central axis of the welding strip 13 , there are two flat surfaces and they are symmetrical about the central axis of the welding strip 13 , and the distance between the two flat surfaces is consistent with the diameter of the welding strip 13 .

[0054] In the embodiment of the present application, a flat surface is provided on the protrusion 131 . The provision of the flat surface facilitates the contact between the welding strip 13 and the welding point 124 . The provision of the protrusion 131 facilitates the battery cell 11 to collect current.

[0055] In one achievable manner of the embodiment of the present application, the soldering strip 13 includes a copper substrate and a coating layer wrapped around the outer periphery of the copper substrate, an aluminum coating layer or a silver coating layer, and the protrusion 131 is a tin structure.

[0056] Copper has a low resistivity and is relatively cheap, which can reduce costs while ensuring current transmission. The material of the coating layer is aluminum or silver, so that the surface of the welding strip 13 in contact with the light is aluminum and silver. Aluminum and silver have a large reflectivity to light. When light irradiates the welding strip 13, the coating layer reflects the light, so that part of the light is repeatedly reflected between two adjacent welding strips 13 until it finally irradiates the battery cell 11, thereby increasing the light irradiated to the battery cell 11 and further improving the photoelectric conversion efficiency of the solar cell module 10.

[0057] According to the specific structure of the soldering strip 13, the soldering strip 13 is linear and has a plurality of protrusions 131. In practical applications, the substrate of the soldering strip 13 is also linear and has a plurality of protrusions 131. A coating layer is wrapped around the linear substrate and the protrusions to form the soldering strip 13.

[0058] Preferably, the material of the covering layer may be aluminum, because the cost of aluminum is lower than that of silver, which further reduces the cost of the solar cell assembly 10 .

[0059] It should be noted that those skilled in the art may also select other metals according to actual conditions, as long as they can transmit current and have a high reflectivity to light.

[0060] The tin structure can be coated on the surface of the soldering strip 13 by hot-dip or electroplating process. Tin can be melted at a relatively low temperature. During the soldering process of the soldering strip 13, the tin structure is heated and melted, and automatically flows into the hole to level the height difference, thereby achieving the soldering requirements. Therefore, the soldering strip 13 provided in the embodiment of the present application can be melted by the tin structure, and then use its fluidity to flow to the lower place to level the height difference and then achieve soldering, and the precision requirement is relatively low.

[0061] Another aspect of the present invention provides a solar cell assembly 10, such as Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown, it includes a battery cell 11 and a grid line structure 12 respectively arranged on both sides of the battery cell 11, the grid line structure 12 at least includes a plurality of first grid lines 121 arranged along a first direction, each grid line extends along a second direction, and the first grid line 121 is connected to a side away from the battery cell 11 with a welding strip 13 as described above, the welding strip 13 extends along the first direction, and the protrusions 131 on the welding strip 13 are respectively connected to the first grid lines 121, and the first direction is perpendicular to the second direction. The solar cell assembly includes the same structure and beneficial effects as the above-mentioned welding strip, which will not be repeated here.

[0062] In one implementable manner of the embodiment of the present application, the gate line structure 12 also includes a plurality of second gate lines 122 arranged along the second direction, the plurality of second gate lines 122 extend along the first direction, and are cross-connected with the first gate lines 121 to form connection points 123, the welding strips 13 include a plurality of strips, and the plurality of welding strips 13 are respectively arranged on the second gate lines 122, wherein the width of the second gate lines 122 is between 30-60 μm.

[0063] Specifically, the width of the first grid line 121 and the second grid line 122 are both between 30-60 μm. The width of the first grid line 121 and the second grid line 122 is greatly reduced compared to the hundreds of microns in the prior art, thereby reducing the amount of silver paste used; in addition, the projection area of ​​the first grid line 121 and the second grid line 122 on the cell 11 is reduced, thereby increasing the area of ​​the cell 11 receiving light, thereby improving the photoelectric conversion efficiency of the solar cell module 10.

[0064] The welding strips 13 are arranged on the second grid lines 122, and the number of the welding strips 13 is the same as the number of the second grid lines 122. The welding strips 13 are connected to the second grid lines 122 one by one, that is, a welding strip 13 is arranged on each second grid line 122. In this way, the distribution of the welding strips 13 on the battery cell 11 is relatively dense, so that the current generated on the battery cell 11 can be timely discharged through the welding strips 13, thereby realizing timely current collection.

[0065] It should be noted that, in order to make the structure of the second gate line 122 clearer, Figure 1 The welding strip 13 is not marked on the top second gate line 122 . In actual application, the top second gate line 122 is the same as other second gate lines 122 . The welding strip 13 is arranged on the second gate line 122 and connected to the second gate line 122 through the welding point 124 .

[0066] In one achievable manner of the embodiment of the present application, the number of connection points 123 on a second gate line 122 is greater than the number of protrusions 131 on the corresponding welding strip 13 , and the distance between two adjacent protrusions 131 is an integer multiple of the distance between two adjacent connection points 123 .

[0067] The spacing between the first grid lines 121 is relatively small, so that the number of connection points 123 on the second grid lines 122 is relatively large. In order to further reduce the obstruction of the surface of the battery cell 11 by the protrusions 131, the present application sets the number of connection points 123 on the second grid lines 122 to be greater than the number of protrusions 131 on the corresponding welding strips 13, that is, some of the connection points 123 form welding points 124, and the welding points 124 correspond one-to-one with the protrusions 131 on the welding strips 13. In this way, the number of protrusions 131 can be reduced, thereby reducing the obstruction of the surface of the battery cell 11 by the protrusions 131, thereby improving the photoelectric conversion efficiency.

[0068] Optional, such as Figure 1 As shown, the number of welding points 124 between a second gate line 122 and a corresponding welding strip 13 is between 6 and 12.

[0069] The number of welding points 124 between a second gate line 122 and a corresponding welding strip 13 is between 6 and 12, that is, the welding strip 13 connected to a second gate line 122 has 6 to 12 protrusions 131, and the number of welding points 124 is reduced while ensuring the collection current.

[0070] Optionally, the gate line structure 12 and the welding strip 13 are connected by welding, and the welding temperature of the welding connection is between 130° C. and 160° C.

[0071] The grid line structure 12 and the welding strip 13 are connected, that is, the protrusion 131 of the welding strip 13 is connected to the welding point 124 of the grid line structure 12. Specifically, the protrusion 131 is made of a conductive material, and the protrusion 131 is connected to the welding point 124 after melting and solidifying. The embodiment of the present application uses a relatively low temperature welding to connect the protrusion 131 and the welding point 124, which avoids the deformation of the welding strip 13 at high temperature, resulting in the tension of the welding strip 13, thereby reducing the tension between the welding strip 13 and the battery cell 11, thereby avoiding the deviation of the welding strip 13 during the lamination process of multiple battery cells 11. Specifically, the welding temperature is between 130°C and 160°C, and can be 150°C for example.

[0072] Specifically, the embodiment of the present application does not limit the method of welding at a relatively low temperature. For example, ultraviolet irradiation may be used to melt the protrusion 131 .

[0073] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A solar cell assembly, comprising a cell, wherein the cell comprises a grid line structure arranged on two sides of the cell, characterized in that: The gate line structure at least includes a plurality of first gate lines arranged along a first direction, and the first gate lines extend along a second direction; The solar cell assembly further includes a welding strip for welding the cell sheet, the welding strip is linear and extends along a first direction, the welding strip has a plurality of protrusions, the plurality of protrusions are arranged at intervals on the welding strip, the arrangement path of the plurality of protrusions is consistent with the extension path of the welding strip, the spacing between two adjacent protrusions is equal to the spacing between adjacent welding points on the cell sheet, and the protrusions are respectively connected to the first grid lines, and the first direction is perpendicular to the second direction; The gate line structure further includes a plurality of second gate lines arranged along a second direction, wherein the plurality of second gate lines extend along the first direction and cross-connect with the first gate lines to form connection points; The number of connection points on one of the second gate lines is not less than the number of the protrusions on the corresponding welding strip, and the distance between two adjacent protrusions is an integer multiple of the distance between two adjacent connection points.

2. The solar cell assembly according to claim 1, characterized in that: The welding strips include a plurality of strips, and the plurality of welding strips are respectively arranged on the second gate lines, wherein the width of the second gate lines is between 30-60 μm.

3. The solar cell assembly according to claim 2, characterized in that: The number of welding points between one of the second gate lines and a corresponding one of the welding strips is between 6 and 12.

4. The solar cell assembly according to claim 1, characterized in that: The maximum dimension of the cross section of the welding strip is between 0.15-0.2 mm, and the maximum dimension of the cross section of the protrusion is between 0.2-0.8 mm.

5. The solar cell assembly according to claim 1, characterized in that: Along the extension direction of the welding strip, the cross-section of the protrusion has a shape of one of a square, a rectangle, a trapezoid, a circle, a semicircle and a rhombus.

6. The solar cell assembly according to claim 1, characterized in that: Along the extending direction of the welding strip, The cross-sectional areas of the protrusions are the same; Alternatively, the cross-sectional area of ​​the protrusion first gradually increases and then gradually decreases.

7. The solar cell assembly according to claim 1, characterized in that: The protruding portion has a flat surface parallel to the central axis of the welding strip; there are two flat surfaces which are symmetrical about the central axis of the welding strip, and the distance between the two flat surfaces is consistent with the diameter of the welding strip.

8. The solar cell assembly according to claim 1, characterized in that: The welding strip comprises a copper substrate and an aluminum coating layer or a silver coating layer wrapped around the outer periphery of the copper substrate, and the protruding portion is a tin structure.

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