A back contact cell assembly
By designing cell overlap and conductive strip connection in the back contact cell module, the problems of deformation and reduced power generation caused by high back stress were solved, achieving balanced stress and improved power generation of the module.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- TIANJIN ZHONGHUAN SEMICON CO LTD
- Filing Date
- 2025-07-29
- Publication Date
- 2026-07-14
AI Technical Summary
In existing back-contact solar cell modules, the high stress on the back of the cells can lead to module deformation or breakage, and the spacing between the cells reduces the module area and thus the power generation.
The design employs multiple solar cells that are sequentially overlapped along a first direction. Each solar cell has first and second conductive connection areas with different polarities on its back side. The ends of the solar cells overlap each other and are connected by conductive strips. There are solder strips on both the front and back sides of the module to eliminate gaps between adjacent solar cells.
This solves the problem of uneven stress in solar cell modules, avoids deformation and fragmentation, and increases the power generation of the modules without increasing costs.
Smart Images
Figure CN224503863U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of photovoltaic module technology, and in particular to a back-contact cell module. Background Technology
[0002] With the rapid development of photovoltaic technology, solar cell manufacturing processes have evolved from PERC to TOPCon and HJT technologies, increasing cell efficiency from 23% to 26%, and the latest BC cells have further improved efficiency to around 27%. BC cells, also known as back-contact cells, are cells where both positive and negative electrodes are integrated on the back. The front of a BC cell uses a grid-less design, allowing it to absorb more sunlight.
[0003] Current BC (Browser-Based Cell) modules are formed using conventional welding processes. Specifically, the cells are laid out flat and then connected in series using welding wire. Since BC cells only have electrodes on the back side, the welding wire in conventional processes is also entirely on the back of the cells. This results in higher stress on the back of the cells, making them prone to bending and causing deformation or even breakage of the module. Furthermore, the cells in conventional processes have a certain spacing, which occupies the overall area of the module, thus reducing the module's power generation. Utility Model Content
[0004] The purpose of this invention is to provide a back-contact solar cell assembly to solve the technical problems of deformation or even fragmentation of the solar cell assembly caused by the large back stress of the back contact solar cells in the prior art, as well as the technical problem that the spacing of the solar cells will reduce the power generation of the solar cell assembly.
[0005] To achieve the above objectives, the present invention adopts the following technical solution:
[0006] A back-contact battery cell assembly includes a plurality of battery cells arranged to overlap sequentially, each of the battery cells having a first end and a second end along a first direction, the first direction being the sequential arrangement direction of the plurality of battery cells;
[0007] Wherein, on the back of each of the battery cells, a first conductive connection area is provided at the edge of the first end of the battery cell, and a second conductive connection area is provided at the edge of the second end of the battery cell. The first conductive connection area corresponds to a first polarity and the second conductive connection area corresponds to a second polarity. The first polarity is different from the second polarity.
[0008] In the plurality of battery cells, one of the first end and the second end of each battery cell overlaps with the other of the first end and the second end of an adjacent battery cell, and one of the first conductive connection area and the second conductive connection area of each battery cell is connected to the other of the first conductive connection area and the second conductive connection area of an adjacent battery cell.
[0009] In some embodiments, each of the solar cells includes a plurality of first main grids and a plurality of second main grids extending along the first direction, the plurality of first main grids and the plurality of second main grids being alternately arranged in a second direction perpendicular to the first direction;
[0010] Each of the battery cells further includes a plurality of first conductive connection portions, each of which is connected to a corresponding first main grid among the plurality of first main grids;
[0011] The second conductive connection region of each of the solar cells further includes a plurality of second conductive connection portions, each of which is connected to a corresponding second main grid among the plurality of second main grids.
[0012] In some embodiments, each of the plurality of first main grids has a first end and a second end, the first end of each first main grid is located at a first end of the solar cell, and the second end of each first main grid is located at a second end of the solar cell;
[0013] Each of the plurality of second main grids has a first end and a second end, the first end of each second main grid is located at the first end of the solar cell, and the second end of each second main grid is located at the second end of the solar cell;
[0014] At the first end of the battery cell, the first end of each first main gate is aligned with a first alignment line; the first end of each second main gate is aligned with a second alignment line, and the second alignment line is recessed relative to the first alignment line by a first predetermined distance; and
[0015] At the second end of the battery cell, the second end of each of the first main gates is aligned with a first alignment line at the second end; the second end of each of the second main gates is aligned with a second alignment line at the second end, and the first alignment line at the second end is recessed by a second predetermined distance relative to the second alignment line at the second end.
[0016] Wherein, the first alignment line of the first end, the second alignment line of the first end, the first alignment line of the second end, and the second alignment line of the second end are all parallel to the second direction.
[0017] In some embodiments, the first predetermined distance is 1mm-10mm;
[0018] The second predetermined distance is 1mm-10mm;
[0019] The vertical distance between the first alignment line at the first end and the edge of the battery cell at the first end is less than or equal to 5 mm;
[0020] The vertical distance between the second alignment line at the second end and the edge of the battery cell at the second end is less than or equal to 5 mm.
[0021] In some embodiments, the first polarity includes one of the N-pole and the P-pole, and the second polarity includes the other of the N-pole and the P-pole.
[0022] In some embodiments, at least one side of each first main gate is provided with a plurality of first fine gates distributed sequentially along its extension direction;
[0023] At least one side of each second main gate has a plurality of second fine gates distributed sequentially along its extension direction.
[0024] In some embodiments, the first and second fine gates intersect each other between adjacent first and second main gates.
[0025] In some embodiments, the plurality of battery cells includes two end battery cells and a plurality of middle battery cells located between the two end battery cells, wherein:
[0026] One of the end cells has a first conductive connection area connected to a first busbar, and the other end cell has a second conductive connection area connected to a second busbar;
[0027] In the plurality of central battery cells, the first conductive connection area of each central battery cell is connected to the second conductive connection area of the battery cell adjacent to its first end, and its second conductive connection area is connected to the first conductive connection area of the battery cell adjacent to its second end.
[0028] In some embodiments, in the plurality of battery cells, one of the first conductive connection region and the second conductive connection region of each battery cell is connected to the other of the first conductive connection region and the second conductive connection region of an adjacent battery cell via a conductive strip.
[0029] In some embodiments, the cross-section of the conductive strip is U-shaped or V-shaped;
[0030] And / or, the length of the conductive strip is less than or equal to the width of the back side of the battery cell, and the width direction of the back side of the battery cell is perpendicular to the first direction;
[0031] And / or, the thickness of the conductive strip ranges from 20 μm to 100 μm;
[0032] And / or, the conductive strip is made of copper foil with a coating on its surface, and the coating is made of one or more of tin, lead, silver, bismuth, and copper.
[0033] The beneficial effects of this utility model are:
[0034] The back-contact solar cell assembly provided by this utility model includes multiple solar cells sequentially overlapped along a first direction. Each solar cell has a first end and a second end along the first direction. On the back side of each solar cell, a first conductive connection area and a second conductive connection area with different polarities are respectively provided at the edges of the first end and the second end of the solar cell. One of the first end and the second end of each solar cell overlaps with the other of the first end and the second end of an adjacent solar cell, and one of the first conductive connection areas and the second conductive connection area of each solar cell connects with the other of the first conductive connection area and the second conductive connection area of an adjacent solar cell. Because the multiple solar cells are connected by overlapping, the front and back sides of the assembly have solder strips, avoiding the problem of high stress on the back side of the assembly caused by conventional assemblies having solder strips only on the back side. At the same time, it eliminates the gap between adjacent solar cells in conventional back-contact assemblies, increasing the power of the assembly within the same size. Attached Figure Description
[0035] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0036] Figure 1 A schematic diagram of the back side of the back contact battery cell assembly provided in an embodiment of this utility model;
[0037] Figure 2 A frontal schematic diagram of a back-contact battery cell assembly using a first stacking method, provided in an embodiment of this utility model.
[0038] Figure 3 A frontal view of the back contact battery cell assembly provided in this embodiment of the present invention when the second stacking method is adopted;
[0039] Figure 4 for Figure 1 Enlarged view of point A in the middle;
[0040] Figure 5 A schematic diagram of the back side of one of the battery cells in the back contact battery cell assembly provided in this embodiment of the utility model;
[0041] Figure 6 forFigure 5 Enlarged view of point B in the middle;
[0042] Figure 7 for Figure 5 A magnified view of point C in the middle.
[0043] icon:
[0044] 1-Battery cell; 11-First main grid; 12-Second main grid; 13-First fine grid; 14-Second fine grid; 15-First conductive connection; 16-Second conductive connection;
[0045] 2-Conductive strip; 21-First connecting segment; 22-Second connecting segment;
[0046] 3-First busbar;
[0047] 4-Second busbar;
[0048] 100 - First alignment line of the first end; 200 - Second alignment line of the first end; 300 - First alignment line of the second end; 400 - Second alignment line of the second end. Detailed Implementation
[0049] The technical solution of this utility model will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.
[0050] It should be noted that in the description of this utility model, the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used solely for the convenience of describing this utility model and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.
[0051] It should be noted that in the description of this utility model, the terms "connection" and "installation" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or a connection through an intermediate medium; they can refer to a mechanical connection or an electrical connection. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.
[0052] Currently, the welding wires in back-contact solar cell modules are all located on the back of the cells, resulting in higher stress on the back of the cells and causing deformation or even breakage of the modules. Furthermore, the spacing between cells in conventional solar cell modules occupies more of the overall module area, reducing the module's power generation.
[0053] Based on this, this application provides a back-contact solar cell assembly, referring to... Figures 1 to 3 The component includes a plurality of battery cells 1 arranged to overlap sequentially, each battery cell 1 having a first end and a second end along a first direction, the first direction being the direction in which the plurality of battery cells 1 are arranged sequentially.
[0054] In each of the battery cells 1, a first conductive connection area is provided on the edge of the first end of the battery cell 1 on the back side, and a second conductive connection area is provided on the edge of the second end of the battery cell 1. The first conductive connection area corresponds to the first polarity and the second conductive connection area corresponds to the second polarity. The first polarity is different from the second polarity.
[0055] In this configuration, among the multiple battery cells 1, one of the first end and the second end of each battery cell 1 overlaps with the other of the first end and the second end of its adjacent battery cell 1, and one of the first conductive connection area and the second conductive connection area of each battery cell 1 is connected to the other of the first conductive connection area and the second conductive connection area of its adjacent battery cell 1.
[0056] It should be noted that the first end and the second end of the battery cell 1 are two ends in a relative sense. When one end of the battery cell 1 along the first direction is the first end, then the other end along the first direction is the second end. Figure 2 In the structure shown, the left end of each solar cell 1 is the first end, and its right end is the second end; in any two adjacent solar cells 1, the back of the first end of the right solar cell 1 overlaps the front of the second end of the left solar cell 1. Of course, the stacking method for multiple solar cells 1 can also be... Figure 3 In the structure shown, the left end of each battery cell 1 is the second end, and its right end is the first end; in any two adjacent battery cells 1, the back of the second end of the right battery cell 1 overlaps the front of the first end of the left battery cell 1. Figure 2 and Figure 3 As shown, the first conductive connection area and the second conductive connection area can be designed such that the first conductive connection area is above the second conductive connection area, or the first conductive connection area is below the second conductive connection area, depending on the actual situation.
[0057] The back-contact solar cell module provided in this application has the following advantages: First, the stacking design of adjacent solar cells 1 ensures that there are solder strips on both the front and back sides of the module, making the stress on the front and back sides of the module relatively balanced. This avoids the problem of high stress on the back side of the module, easy bending and fragmentation of the solar cells, which is caused by the conventional back-contact module having solder wires only on the back side, thus improving the quality of the module. Second, the ends of two adjacent solar cells 1 are overlapped vertically, eliminating the gap between adjacent solar cells in conventional back-contact modules, thereby increasing the power of the module within the same size.
[0058] As an optional embodiment, the type of battery cell 1 can be any one of IBC battery, TBC battery, or HBC battery. All three types of batteries are back-contact batteries and can all utilize the string welding structure provided in this application.
[0059] As an optional embodiment, the side length of the battery cell 1 ranges from 125mm to 250mm, which can basically cover all sizes of back contact battery cells.
[0060] In this embodiment, the first polarity includes one of the N-pole and the P-pole, and the second polarity includes the other of the N-pole and the P-pole; specifically, the first conductive connection region corresponds to the N-pole, and the second conductive connection region corresponds to the P-pole.
[0061] Continue to refer to Figure 1 and Figure 2 In this embodiment, among the multiple solar cells 1, one of the first conductive connection area and the second conductive connection area of each solar cell 1 is connected to the other of the first conductive connection area and the second conductive connection area of its adjacent solar cell 1 via a conductive strip 2. Specifically, the conductive strip 2 is a solder strip, and each pair of adjacent solar cells 1 is connected by a conductive strip 2 for series welding. This embodiment uses a long conductive strip 2 instead of conventional welding wire, making the welding edges of the solar cells 1 more evenly stressed, reducing the breakage rate of the module during lamination, and improving the welding strength.
[0062] Continue to refer to Figure 1 and Figure 2 The back-contact battery cell assembly also includes a first busbar 3 and a second busbar 4 connected to both ends of the battery string, which collect the current of the battery string. Specifically, the plurality of battery cells 1 include two end battery cells and a plurality of middle battery cells located between the two end battery cells, wherein: the first conductive connection area of one end battery cell is connected to the first busbar 3, and the second conductive connection area of the other end battery cell is connected to the second busbar 4; among the plurality of middle battery cells, the first conductive connection area of each middle battery cell is connected to the second conductive connection area of the battery cell 1 adjacent to its first end, and its second conductive connection area is connected to the first conductive connection area of the battery cell 1 adjacent to its second end.
[0063] In some embodiments, such as Figure 2 As shown, the conductive strip 2 has a U-shaped cross-section and includes a first connecting section 21, a second connecting section 22, and a transition section, wherein the transition section connects the ends of the first connecting section 21 and the second connecting section 22. In two adjacent battery cells 1, the first conductive connection area on one battery cell 1 is welded to the first connecting section 21, and the second conductive connection area on the other battery cell 1 is welded to the second connecting section 22.
[0064] In some other embodiments, the cross-section of the conductive strip 2 can also be V-shaped. Compared to a V-shaped conductive strip 2, a U-shaped conductive strip 2 allows the solder strip to fit more closely to the battery cell 1, thereby improving the welding quality.
[0065] In some embodiments, the length of the conductive strip 2 is less than or equal to the width of the back surface of the battery cell 1, and the width direction of the back surface of the battery cell 1 is perpendicular to the first direction. (Refer to...) Figure 4 The length of the conductive strip 2 should not be greater than the width of the cell 1, so as to prevent the two ends of the conductive strip 2 from extending to the outside of the back of the module; at the same time, the length of the conductive strip 2 should be such that the conductive strip 2 can cover the first conductive connection area on one of the two adjacent cells 1 and the second conductive connection area on the other cell 1.
[0066] In some embodiments, the thickness of the conductive strip 2 ranges from 20 μm to 100 μm. For example, the thickness of the conductive strip 2 is any one of 20 μm, 25 μm, 40 μm, 60 μm, 75 μm, 84 μm, 91 μm, and 100 μm. If the conductive strip 2 is too thin, weak welding may occur; if the conductive strip 2 is too thick, the overall thickness of the component will be too high. Setting the thickness of the conductive strip 2 within the range of 20 μm to 100 μm ensures strong welding without excessively increasing the overall thickness of the component.
[0067] In some embodiments, the conductive strip 2 is made of copper foil with a surface coating, the coating being one or more of tin, lead, silver, bismuth, and copper. Copper foil solder strips have advantages such as light weight, low cost, and strong corrosion resistance. The coating on the surface of the copper foil can optimize the performance of the solder strip. For example, aluminum foil with a tin, silver, or lead coating has higher oxidation and corrosion resistance, while also reducing incomplete soldering and improving weld strength; aluminum foil with a copper coating has higher conductivity, which can reduce energy loss during current transmission.
[0068] In some embodiments, refer to Figure 2 and Figure 3In two adjacent solar cells 1, the first conductive connection area of one solar cell 1 and the second conductive connection area of the other solar cell 1 coincide on the orthographic projection of the back side of either solar cell 1. This arrangement ensures that the solder strips on the front and back sides of the module coincide vertically, which helps to balance the welding stress on the front and back sides of the module.
[0069] Furthermore, referring to Figures 5 to 7 Each battery cell 1 includes a plurality of first main grids 11 and a plurality of second main grids 12 extending along a first direction, the plurality of first main grids 11 and the plurality of second main grids 12 being alternately arranged in a second direction, the second direction being perpendicular to the first direction;
[0070] Each battery cell 1's first conductive connection area further includes a plurality of first conductive connection portions 15, each of which is connected to a corresponding first main grid 11 among the plurality of first main grids 11;
[0071] The second conductive connection area of each cell 1 further includes a plurality of second conductive connection portions 16, each of which is connected to a corresponding second main grid 12 among the plurality of second main grids 12.
[0072] In this embodiment, the first main grid 11 corresponds to the N pole, and the second main grid 12 corresponds to the P pole. The first main grid 11 and the second main grid 12 are alternately distributed side by side along the second direction. This layout can maximize the utilization of the back area of the battery cell 1 and make the power of the module optimal.
[0073] Furthermore, each first main grid 11 has a first end and a second end. The first end of each first main grid 11 is located at the first end of the solar cell 1, and the second end of each first main grid 11 is located at the second end of the solar cell 1. The first end of each first main grid 11 is connected to a corresponding first conductive connection portion 15. Each second main grid 12 has a first end and a second end. The first end of each second main grid 12 is located at the first end of the solar cell 1, and the second end of each second main grid 12 is located at the second end of the solar cell 1. The second end of each second main grid 12 is connected to a corresponding second conductive connection portion 16. Through the above arrangement, the current on each main grid is ultimately guided to the corresponding conductive connection portion.
[0074] In some embodiments, each first conductive connection portion 15 and each second conductive connection portion 16 is provided with a solder pad, which can be one of various shapes such as square, round, rhomboid, semi-circular, or concave-convex. By providing solder pads, the welding area between the conductive connection portion and the conductive strip 2 can be increased, thereby improving the welding strength.
[0075] Based on the above structure, in some embodiments, at least one side of each first main gate 11 is provided with a plurality of first fine gates 13 along its extending direction;
[0076] At least one side of each second main gate 12 has a plurality of second fine gates 14 distributed sequentially along its extension direction.
[0077] In this embodiment, in the two main grids located on both sides of the battery cell 1, a plurality of fine grids are sequentially distributed on the inner side of each main grid along its extension direction; in each main grid located between the two edge main grids, a plurality of fine grids are sequentially distributed on the opposite sides of each main grid along its extension direction.
[0078] Furthermore, between adjacent first main grids 11 and second main grids 12, first fine grids 13 and second fine grids 14 interweave with each other. For example... Figure 6 and Figure 7 As shown, each of the first main grids 11 in the middle is connected to multiple first fine grids 13 on both sides, and each of the second main grids 12 in the middle is connected to multiple second fine grids 14 on both sides; between adjacent first main grids 11 and second main grids 12, the first fine grids 13 and the second fine grids 14 are alternately distributed and form a forked structure, which maximizes the use of the area on the back of the solar cell without interfering with each other.
[0079] In some embodiments, refer to Figure 6 At the first end of the battery cell 1, the first end of each first main busbar 11 is aligned with a first alignment line 100; the first end of each second main busbar 12 is aligned with a second alignment line 200, and the second alignment line 200 is recessed by a first predetermined distance relative to the first alignment line 100. (Refer to...) Figure 7 At the second end of the battery cell 1, the second end of each first main grid 11 is aligned with a second end first alignment line 300; the second end of each second main grid 12 is aligned with a second end second alignment line 400, and the second end first alignment line 300 is recessed relative to the second end second alignment line 400 by a second predetermined distance. The first end first alignment line 100, the first end second alignment line 200, the second end first alignment line 300, and the second end second alignment line 400 are all parallel to a second direction. Figure 6 and Figure 7 The two dashed lines in the diagram represent two alignment lines.
[0080] The above arrangement causes the first conductive connection portion 15 and the first end of the second main grid 12 to be misaligned in the first direction, and at the same time, causes the second conductive connection portion 16 and the second end of the first main grid 11 to be misaligned in the first direction, thereby preventing the conductive strip 2 from connecting the first main grid 11 and the second main grid 12 on the same battery cell 1 and causing a short circuit.
[0081] Based on the above structure, the first predetermined distance is 1mm-10mm, preferably within the range of 1mm-2mm. The second predetermined distance is 1mm-10mm, preferably within the range of 1mm-2mm.
[0082] like Figure 6 and Figure 7 As shown, at one end of the first conductive connection portion 15 near the side, the second main grid 12 and the second fine grid 14 are recessed towards the center of the back side by 1-10mm (preferably 1mm-2mm) so that the end of the second main grid 12 does not contact the conductive strip 2, preventing the conductive strip 2 from connecting the ends of the first conductive connection portion 15 and the second main grid 12 on the same cell 1 after stacking; similarly, at one end of the second conductive connection portion 16 near the side, the first main grid 11 and the first fine grid 13 are recessed towards the center of the back side by 1-10mm (preferably 1mm-2mm) so that the end of the first main grid 11 does not contact the conductive strip 2.
[0083] Continue to refer to Figure 6 and Figure 7 In some embodiments, the vertical distance between the first alignment line 100 at the first end and the edge of the battery cell 1 at the first end is less than or equal to 5 mm, preferably less than or equal to 2 mm. The vertical distance between the second alignment line 400 at the second end and the edge of the battery cell 1 at the second end is less than or equal to 5 mm, preferably less than or equal to 2 mm.
[0084] The distance between the conductive connection and the edge of the same-side battery cell is generally between 0.1mm and 5mm (preferably between 0.1mm and 2mm). The conductive connection cannot extend beyond the edge of the battery cell and be located on the outer side of the back of the battery cell. For example, the distance between the conductive connection and the edge of the same-side battery cell is any value among 0.1mm, 1mm, 2mm, 3mm, 4mm, and 5mm.
[0085] In summary, in the back-contact solar cell assembly provided in this embodiment, each solar cell 1 has a first main grid 11, a second main grid 12, a first fine grid 13, and a second fine grid 14 on its back side. The first main grid 11 is connected to the first fine grid 13, ultimately leading to the first conductive connection portion 15 at the first end of the solar cell 1; the second main grid 12 is connected to the second fine grid 14, ultimately leading to the second conductive connection portion 16 at the second end of the solar cell 1. Multiple solar cells 1 are connected in series via conductive strips 2, which connect the N and P poles of adjacent solar cells 1 to form a conductive circuit. This assembly, through the special configuration of the conductive strips 2 and the overlapping design of the ends of adjacent solar cells 1, ensures that both the front and back sides of the assembly have solder strips. This avoids the problems of high stress on the back side of the assembly, easy bending of the solar cells, and breakage caused by conventional back-contact assemblies only having solder wires on the back side. Simultaneously, there are no gaps between adjacent solar cells 1, increasing the power output of the assembly within the same size. Furthermore, the back-contact solar cell assembly provided in this embodiment achieves significant results without increasing costs, thus achieving the goal of cost reduction and efficiency improvement.
[0086] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.
Claims
1. A back-contact solar cell assembly, characterized in that: It includes a plurality of battery cells (1) arranged to overlap in sequence, each of the battery cells (1) having a first end and a second end along a first direction, the first direction being the direction in which the plurality of battery cells (1) are arranged in sequence; Wherein, on the back side of each of the battery cells (1), a first conductive connection area is provided at the edge of the first end of the battery cell (1), and a second conductive connection area is provided at the edge of the second end of the battery cell (1). The first conductive connection area corresponds to a first polarity and the second conductive connection area corresponds to a second polarity. The first polarity is different from the second polarity. Among the plurality of battery cells (1), one of the first end and the second end of each battery cell (1) overlaps with the other of the first end and the second end of its adjacent battery cell (1), and one of the first conductive connection area and the second conductive connection area of each battery cell (1) is connected with the other of the first conductive connection area and the second conductive connection area of its adjacent battery cell (1).
2. The back contact cell assembly according to claim 1, characterized in that: Each of the solar cells (1) includes a plurality of first main grids (11) and a plurality of second main grids (12) extending along the first direction, the plurality of first main grids (11) and the plurality of second main grids (12) being alternately arranged in a second direction perpendicular to the first direction; The first conductive connection area of each of the battery cells (1) further includes a plurality of first conductive connection portions (15), each of which is connected to a corresponding first main grid (11) among the plurality of first main grids (11); The second conductive connection area of each of the battery cells (1) further includes a plurality of second conductive connection portions (16), each of which is connected to a corresponding second main grid (12) among the plurality of second main grids (12).
3. The back-contact battery cell assembly according to claim 2, characterized in that: Each of the plurality of first main grids (11) has a first end and a second end, the first end of each first main grid (11) being located at the first end of the battery cell (1), and the second end of each first main grid (11) being located at the second end of the battery cell (1); Each of the plurality of second main grids (12) has a first end and a second end, the first end of each second main grid (12) being located at the first end of the battery cell (1), and the second end of each second main grid (12) being located at the second end of the battery cell (1); At the first end of the battery cell (1), the first end of each first main grid (11) is aligned with the first end first alignment line (100); the first end of each second main grid (12) is aligned with the first end second alignment line (200), and the first end second alignment line (200) is recessed by a first predetermined distance relative to the first end first alignment line (100); as well as At the second end of the battery cell (1), the second end of each of the first main grids (11) is aligned with the second end first alignment line (300); the second end of each of the second main grids (12) is aligned with the second end second alignment line (400), and the second end first alignment line (300) is recessed by a second predetermined distance relative to the second end second alignment line (400); The first alignment line (100), the second alignment line (200), the first alignment line (300), and the second alignment line (400) at the first end are parallel to the second direction.
4. The back-contact battery cell assembly according to claim 3, characterized in that: The first predetermined distance ranges from 1mm to 10mm; The second predetermined distance ranges from 1mm to 10mm; The vertical distance between the first alignment line (100) at the first end and the edge of the battery cell at the first end of the battery cell (1) is less than or equal to 5 mm; The vertical distance between the second alignment line (400) at the second end and the edge of the battery cell at the second end of the battery cell (1) is less than or equal to 5 mm.
5. The back-contact battery cell assembly according to claim 1, characterized in that: The first polarity includes one of the N-pole and the P-pole, and the second polarity includes the other of the N-pole and the P-pole.
6. The back-contact battery cell assembly according to claim 2, characterized in that: At least one side of each of the first main grids (11) has a plurality of first fine grids (13) distributed sequentially along its extension direction. Each of the second main gates (12) has a plurality of second fine gates (14) distributed sequentially on at least one side along its extension direction.
7. The back-contact battery cell assembly according to claim 6, characterized in that: Between adjacent first main gate (11) and second main gate (12), the first fine gate (13) and the second fine gate (14) interweave with each other.
8. The back-contact battery cell assembly according to claim 1, characterized in that: The plurality of battery cells (1) includes two end battery cells and a plurality of middle battery cells located between the two end battery cells, wherein: One of the end cells has a first conductive connection area connected to a first busbar (3), and the other end cell has a second conductive connection area connected to a second busbar (4); In the plurality of central battery cells, the first conductive connection area of each central battery cell is connected to the second conductive connection area of the battery cell (1) adjacent to its first end, and its second conductive connection area is connected to the first conductive connection area of the battery cell (1) adjacent to its second end.
9. The back-contact solar cell assembly according to any one of claims 1 to 8, characterized in that: In the plurality of battery cells (1), one of the first conductive connection area and the second conductive connection area of each battery cell (1) is connected to the other of the first conductive connection area and the second conductive connection area of the adjacent battery cell (1) by a conductive strip (2).
10. The back-contact solar cell assembly according to claim 9, characterized in that: The cross-section of the conductive strip (2) is U-shaped or V-shaped; And / or, the length of the conductive strip (2) is less than or equal to the width of the back side of the battery cell (1), and the width direction of the back side of the battery cell (1) is perpendicular to the first direction; And / or, the thickness of the conductive strip (2) is in the range of 20 μm - 100 μm; And / or, the conductive strip (2) is made of copper foil with a coating on its surface, and the coating is made of one or more of tin, lead, silver, bismuth and copper.