Solar cell string and photovoltaic module
By introducing auxiliary welding strip sections into the photovoltaic welding strips, the number and cross-sectional area of the backlight photovoltaic welding strips are increased, and the problem of high backlight transmission loss in photovoltaic modules is solved, which improves the output power and avoids optical losses.
Patent Information
- Application Number
- CN202421895521.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-06
- Publication Date
- 2025-07-18
- Estimated Expiration
- 2034-08-06
AI Technical Summary
In existing photovoltaic modules, the photovoltaic welding tape on the backlight surface has high transmission loss, which affects the output power.
The auxiliary welding tape section is introduced into the photovoltaic welding tape, increasing the number of photovoltaic welding tapes and cross-sectional area on the backlight surface, and reducing transmission losses through the connection between the front main welding tape section and the back main welding tape section.
The photovoltaic welding tape transmission loss on the backlight surface is reduced, the output power of the photovoltaic module is increased, and optical losses caused by the obstruction of the light-receiving surface is avoided.
Smart Images
Figure CN223125216U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of solar power generation, and in particular to a solar cell string and a photovoltaic module. Background Art
[0002] Photovoltaic modules can convert light energy into electrical energy and are widely used in daily life. Generally, a photovoltaic module includes a plurality of cells and a photovoltaic ribbon, and the photovoltaic ribbon connects two adjacent cells in series.
[0003] The photovoltaic ribbon includes a front ribbon and a back ribbon. The front ribbon covers the main grid line on the light-receiving side, and the back ribbon covers the main grid line on the backlight side. One end of the front ribbon is connected to one end of the back ribbon. However, such a setting has a high transmission loss of the photovoltaic grid line on the backlight side, which affects the output power of the photovoltaic module. Utility Model Content
[0004] Based on this, it is necessary to provide a solar cell string and a photovoltaic module to reduce the transmission loss of the photovoltaic welding strip on the backlight surface and improve the output power of the photovoltaic module.
[0005] In a first aspect, the present application provides a solar cell string, comprising:
[0006] A battery cell, wherein at least two battery cells are provided, each of the battery cells has a light-receiving surface and a backlight surface, the light-receiving surface is provided with a front grid line, and the backlight surface is provided with a back grid line; and
[0007] Photovoltaic welding strips, wherein a plurality of photovoltaic welding strips are provided, each of the photovoltaic welding strips comprises a front main welding strip segment and a back main welding strip segment, the front main welding strip segment is provided on the light-receiving surface of one of the battery cells, and the front main welding strip segment is connected to the front grid line, the back main welding strip segment is provided on the backlight surface of another adjacent battery cell, and the back main welding strip segment is electrically connected to the back grid line, and the front main welding strip segment is connected to the back main welding strip segment; at least one of the photovoltaic welding strips further comprises an auxiliary welding strip segment, the auxiliary welding strip segment is provided on the backlight surface, and the auxiliary welding strip segment is electrically conductive with the back main welding strip segment.
[0008] In one of the embodiments, the auxiliary welding strip segment is arranged in parallel with the back main welding strip segment, and the outer peripheral surface of the auxiliary welding strip segment is in contact with the outer peripheral surface of the back main welding strip segment.
[0009] In one of the embodiments, the at least one photovoltaic welding strip also includes an auxiliary welding strip segment and a first bent welding strip segment, and the auxiliary welding strip segment is arranged in parallel with the back main welding strip segment; one end of the first bent welding strip segment is connected to one end of the back main welding strip segment away from the front main welding strip segment, and the other end of the first bent welding strip segment is connected to the auxiliary welding strip segment.
[0010] In one embodiment, the at least one photovoltaic welding strip further includes a first bent welding strip segment, a second bent welding strip segment and at least two auxiliary welding strip segments, and all the auxiliary welding strip segments are arranged in parallel with the back main welding strip segment; one end of the first bent welding strip segment is connected to one end of the back main welding strip segment away from the front main welding strip segment, and the other end of the first bent welding strip segment is connected to the auxiliary welding strip segment adjacent to the back main welding strip segment, and both ends of the second bent welding strip segment are respectively connected to two adjacent auxiliary welding strip segments, and the back main welding strip segment, the first bent welding strip segment, the auxiliary welding strip segment and the second bent welding strip segment are connected to form a circuitous structure.
[0011] In one embodiment, the front grid line includes a front main grid line and a front auxiliary grid line, the front main grid line is extended along a first direction, the front auxiliary grid line is extended along a second direction, and the front main welding strip segments are arranged on the front main grid line in a one-to-one correspondence; the back grid line includes a back main grid line and a back auxiliary grid line, the back main grid line is extended along the first direction, the back auxiliary grid line is extended along the second direction, the back main welding strip segments are arranged on the back main grid line in a one-to-one correspondence, and the auxiliary welding strip segments are connected to the back auxiliary grid lines; wherein , the first direction is perpendicular to the second direction; or, the front grid line includes a front auxiliary grid line, the front auxiliary grid line is extended along the second direction or the front auxiliary grid line is in a grid shape, the front main welding band segment is extended along the first direction, and the front main welding band segment is connected to the front auxiliary grid line; the back grid line includes a back auxiliary grid line, the back auxiliary grid line is extended along the second direction or the back auxiliary grid line is in a grid shape, the back main welding band segment is extended along the first direction, and the back main welding band segment and the auxiliary welding band segment are connected to the back auxiliary grid line.
[0012] In one of the embodiments, the number of the auxiliary welding tape segments is an integer multiple of the number of the front main welding tape segments and the back main welding tape segments.
[0013] In one of the embodiments, the front main welding band segment and the back main welding band segment are a continuous integral structure.
[0014] In one of the embodiments, the diameters of the front main welding tape segment, the back main welding tape segment, and the auxiliary welding tape segment are equal.
[0015] In one embodiment, the cross-sectional shapes of the front main solder strip section, the back main solder strip section, and the auxiliary solder strip section are circular; alternatively, the cross-sectional shape of the front main solder strip section is circular, and the cross-sectional shapes of the back main solder strip section and the auxiliary solder strip section are flat, and the cross-sectional areas of the back main solder strip section and the auxiliary solder strip section are larger than the cross-sectional area of the front main solder strip section.
[0016] In a second aspect, the present application further provides a photovoltaic module, including the above-mentioned solar cell string.
[0017] For the above-mentioned solar cell string and photovoltaic module, since each photovoltaic solder strip includes a front main solder strip section and a back main solder strip section, the front grid line of one cell is electrically connected to another adjacent cell through the front main solder strip section and the back main solder strip section, realizing the series connection of two adjacent cells. Since at least one photovoltaic solder strip further includes an auxiliary solder strip section, the auxiliary solder strip section is disposed on the backlight surface and is conducted with the back main solder strip section to increase the number of photovoltaic solder strips on the backlight surface, and correspondingly increase the cross-sectional area of the photovoltaic solder strips on the backlight surface. In this way, the transmission loss of the photovoltaic solder strips on the backlight surface can be reduced, and the output power of the photovoltaic module can be improved. In addition, since the auxiliary solder strip section is not provided on the light-receiving surface of the cell, that is, the number of photovoltaic solder strips on the light-receiving surface is not increased, this can avoid the light-receiving surface of the cell being blocked and avoid optical losses. Description of the Drawings
[0018] Figure 1 It is a schematic structural diagram of the backlight surface of a solar cell string according to an embodiment of the present application.
[0019] Figure 2 is Figure 1 a partial enlarged schematic view of A in
[0020] Figure 3 It is a schematic structural diagram of the backlight surface of a solar cell string according to another embodiment of the present application.
[0021] Figure 4 is Figure 3 a partial enlarged schematic view of B in
[0022] Figure 5 It is a schematic structural diagram of the backlight surface of a solar cell string according to another embodiment of the present application.
[0023] Figure 6 is Figure 5 a partial enlarged schematic view of C in
[0024] Explanation of the Reference Numerals in the Drawings:
[0025] 10. Solar cell; 12. Backlight surface; 20. Photovoltaic welding tape; 22. Main back welding tape segment; 23. Auxiliary welding tape segment; 24. First bent welding tape segment; 25. Second bent welding tape segment. Detailed implementation mode
[0026] To make the above objects, features and advantages of the present application more obvious and understandable, the following will describe the detailed implementation mode of the present application in conjunction with the accompanying drawings. Many specific details are set forth in the following description in order to fully understand the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the connotation of the present application. Therefore, the present application is not limited by the specific embodiments disclosed below.
[0027] Refer to Figure 1 , a solar cell string provided by an embodiment of the present application includes a solar cell 10 and a photovoltaic welding tape 20. There are at least two solar cells 10, and each solar cell 10 has a light-receiving surface and a backlight surface 12. The light-receiving surface is provided with front grid lines, and the backlight surface 12 is provided with back grid lines. The front grid lines of one of the solar cells 10 are electrically connected to the back grid lines of an adjacent other solar cell 10 through the photovoltaic welding tape 20, so that two adjacent solar cells 10 are connected in series.
[0028] Optionally, the front grid lines include front main grid lines and front sub-grid lines. The front main grid lines extend along a first direction, and the front sub-grid lines extend along a second direction. Among them, the first direction is perpendicular to the second direction, and S1 is used to represent the first direction, and S2 is used to represent the second direction. Of course, in other embodiments, the front grid lines may only include front sub-grid lines, and the front sub-grid lines extend along the second direction, or the front sub-grid lines are in a grid structure.
[0029] Optionally, the back grid lines include back main grid lines and back sub-grid lines. The back main grid lines extend along a first direction, and the back sub-grid lines extend along a second direction. Of course, in other embodiments, the back grid lines only include back sub-grid lines, and the back sub-grid lines extend along the second direction, or the back sub-grid lines are in a grid shape.
[0030] In one embodiment, refer to Figure 1 , there are multiple photovoltaic welding tapes 20. Each photovoltaic welding tape 20 includes a front main welding tape segment and a back main welding tape segment 22. The front main welding tape segment is arranged on the light-receiving surface of one of the solar cells 10, and the back main welding tape segment 22 is arranged on the backlight surface 12 of an adjacent other solar cell 10. The front main welding tape segment is connected to the back main welding tape segment 22. At least one photovoltaic welding tape 20 further includes an auxiliary welding tape segment 23, and the auxiliary welding tape segment 23 is arranged on the backlight surface 12 and is in conduction with the back main welding tape segment 22.
[0031] Specifically, if the front grid lines include front main grid lines and front sub-grid lines, the front main solder ribbon segments are disposed on the front main grid lines. If the front grid lines only include front sub-grid lines, the front main solder ribbon segments are disposed on the front sub-grid lines along the first direction.
[0032] Specifically, if the back grid lines include back main grid lines and back sub-grid lines, the back main solder ribbon segments 22 are disposed on the back main grid lines. If the back grid lines only include back sub-grid lines, the back main solder ribbon segments 22 are disposed on the back sub-grid lines along the first direction.
[0033] It should be noted that at least one photovoltaic solder ribbon 20 further includes auxiliary solder ribbon segments 23. It can be understood that some photovoltaic solder ribbons 20 only include front main solder ribbon segments and back main solder ribbon segments 22, and some photovoltaic solder ribbons 20 include front main solder ribbon segments, back main solder ribbon segments 22 and auxiliary solder ribbon segments 23. Alternatively, all photovoltaic solder ribbons 20 include front main solder ribbon segments, back main solder ribbon segments 22 and auxiliary solder ribbon segments 23.
[0034] In the above solar cell string, since each photovoltaic solder ribbon 20 includes a front main solder ribbon segment and a back main solder ribbon segment 22, the front grid lines of one of the cell wafers 10 are electrically connected to another adjacent cell wafer 10 through the front main solder ribbon segment and the back main solder ribbon segment 22, realizing the series connection of two adjacent cell wafers 10. Since at least one photovoltaic solder ribbon 20 further includes auxiliary solder ribbon segments 23, the auxiliary solder ribbon segments 23 are disposed on the backlight surface 12 and are electrically connected to the back main solder ribbon segments 22, so as to increase the number of photovoltaic solder ribbons 20 on the backlight surface 12, and correspondingly increase the cross-sectional area of the photovoltaic solder ribbons 20 on the backlight surface 12. In this way, the transmission loss of the photovoltaic solder ribbons 20 on the backlight surface 12 can be reduced, and the output power of the photovoltaic module can be improved. In addition, since no auxiliary solder ribbon segments 23 are provided on the light-receiving surface of the cell wafer 10, that is, the number of photovoltaic solder ribbons 20 on the light-receiving surface is not increased, this can avoid the light-receiving surface of the cell wafer 10 from being blocked and avoid optical losses.
[0035] In one embodiment, refer to Figure 2 、 Figure 4 and Figure 6 . The auxiliary solder ribbon segments 23 are arranged in parallel with the back main solder ribbon segments 22, and the current flow direction of the auxiliary solder ribbon segments 23 is the same as that of the back main solder ribbon segments 22. Optionally, the auxiliary solder ribbon segments 23 can be parallel to the back main solder ribbon segments 22 or not, as long as it is ensured that the current flow directions of the auxiliary solder ribbon segments 23 and the back main solder ribbon segments 22 are both from the positive pole to the negative pole of two adjacent cell wafers 10.
[0036] In one embodiment, refer to Figure 1 and Figure 2, the auxiliary solder strip segment 23 is in contact with the sub-grid line, and the outer peripheral surface of the auxiliary solder strip segment 23 is in contact with the outer peripheral surface of the back main solder strip segment 22. With such an arrangement, the auxiliary solder strip segment 23 and the back main solder strip segment 22 are in contact to form a whole, and the current collected by the sub-grid line is transmitted through the front main solder strip segment and the back main solder strip segment 22, which is beneficial to reducing the busbar loss.
[0037] It should be noted that in a single photovoltaic solder strip 20, when the number of the auxiliary solder strip segments 23 is one, the outer peripheral surface of the auxiliary solder strip segment 23 is in contact with the outer peripheral surface of the back main solder strip segment 22. When the number of the auxiliary solder strip segments 23 is more than two, all the auxiliary solder strip segments 23 are arranged in parallel with the back main solder strip segment 22, the outer peripheral surfaces of two adjacent auxiliary solder strip segments 23 are in contact, and the outer peripheral surface of the back main solder strip segment 22 is in contact with the outer peripheral surface of the adjacent auxiliary solder strip segment 23.
[0038] In another embodiment, refer to Figure 3 and Figure 5 , at least one end of the back main solder strip segment 22 departing from the front main solder strip segment is bent to form the auxiliary solder strip segment 23. Among them, the number of bends is more than once. In this way, the auxiliary solder strip segment 23 is formed by bending, without the need to additionally increase the number of loading coils of the photovoltaic solder strip 20, improving the convenience of the production of the photovoltaic solder strip 20.
[0039] Optionally, refer to Figure 3 and Figure 4 , when the number of bends is one, there is one auxiliary solder strip segment 23, and the auxiliary solder strip segment 23 is arranged in parallel with the back main solder strip segment 22. At least one photovoltaic solder strip 20 further includes a first bent solder strip segment 24, and two ends of the first bent solder strip segment 24 are respectively connected to the back main solder strip segment 22 and the auxiliary solder strip segment 23. In this way, even if the auxiliary solder strip segment 23 is spaced from the back main solder strip segment 22, the back main solder strip segment 22 and the auxiliary solder strip segment 23 can be electrically connected through the first bent solder strip segment 24.
[0040] Optionally, refer to Figure 5 and Figure 6, when the number of bending times is at least two, there are at least two auxiliary solder tape segments 23, and all the auxiliary solder tape segments 23 are arranged in parallel with the back main solder tape segment 22. Specifically, at least one photovoltaic solder tape 20 further includes a first bent solder tape segment 24 and a second bent solder tape segment 25. One end of the first bent solder tape segment 24 is opposite to the end of the back main solder tape segment 22 away from the front main solder tape segment, and the other end of the first bent solder tape 24 is connected to the auxiliary solder tape segment 23 adjacent to the back main solder tape segment 22. The two ends of the second bent solder tape segment 25 are respectively connected to the ends of two adjacent auxiliary solder tape segments 23. It can be understood that the back main solder tape segment 22, the first bent solder tape segment 24, the auxiliary solder tape segment 23, and the second bent solder tape segment 25 are connected to form a circuitous structure. In this way, even if the auxiliary solder tape segment 23 is spaced from the back main solder tape segment 22, the conduction of the back main solder tape segment 22 and the auxiliary solder tape segment 23 adjacent to the back main solder tape segment 22 can be realized. Even if the two adjacent auxiliary solder tape segments 23 are spaced apart, the conduction of the two adjacent auxiliary solder tape segments 23 can also be realized through the second bent solder tape segment 25.
[0041] In one embodiment, referring to Figure 1 , Figure 3 and Figure 5 , the number of the auxiliary solder tape segments 23 is N times the number of the front main solder tape segments, and the number of the auxiliary solder tape segments 23 is also N times the number of the back main solder tape segments 22. Wherein, N is an integer ≥ 1. Such a setting, on the one hand, ensures the operability of actual production; on the other hand, it can increase the total cross-sectional area of the photovoltaic solder tape 20 on the backlight surface 12, which is beneficial to reducing the transmission loss of the photovoltaic solder tape 20 on the backlight surface 12 and improving the output power of the photovoltaic module.
[0042] In one embodiment, referring to Figure 1 , Figure 3 and Figure 5 , the front main solder tape segment and the back main solder tape segment 22 are a continuous integral structure. It can be understood that the front main solder tape segment and the back main solder tape segment 22 are the two ends of a photovoltaic solder tape 20. One end of the photovoltaic solder tape 20 extends to the light-receiving surface, and the photovoltaic solder tape 20 located on the light-receiving surface is the front main solder tape segment; the other end of the photovoltaic solder tape 20 extends to the backlight surface 12, and the photovoltaic solder tape 20 located on the backlight surface 12 is the back main solder tape segment 22. In this way, it is possible to avoid the lap joint and welding of one end of the front main solder tape segment and one end of the back main solder tape segment 22, and avoid hot spots at the lap joint position.
[0043] In one embodiment, the diameters of the front main solder tape segment, the back main solder tape segment 22, and the auxiliary solder tape segment 23 are equal. Such a setting does not affect the weight of the adhesive film on the backlight surface 12 and avoids an increase in cost.
[0044] It should be noted that the diameters of the front main welding tape section, the back main welding tape section 22, and the auxiliary welding tape section 23 can be set according to actual requirements and are not specifically limited herein.
[0045] In one embodiment, the cross-sectional shapes of the front main welding tape section, the back main welding tape section 22, and the auxiliary welding tape section 23 are the same.
[0046] Optionally, the cross-sectional shapes of the front main welding tape section, the back main welding tape section 22, and the auxiliary welding tape section 23 are circular. In this way, the light-shielding area of the light-receiving surface can be reduced, ensuring the photoelectric conversion efficiency of the solar cell 10, and at the same time facilitating production and processing.
[0047] Of course, in other embodiments, the cross-sectional shape of the front main welding tape section may also be different from the cross-sectional shapes of the back main welding tape section 22 and the auxiliary welding tape section 23. Optionally, the cross-sectional shape of the front main welding tape section is circular, which can reduce the light-shielding area of the light-receiving surface and ensure the photoelectric conversion efficiency of the solar cell 10. The cross-sectional shapes of the back main welding tape section 22 and the auxiliary welding tape section 23 are flat, and the cross-sectional areas of the back main welding tape section 22 and the auxiliary welding tape section 23 are larger than the cross-sectional area of the front main welding tape section. In this way, the total cross-sectional area of the photovoltaic welding tape 20 on the backlight surface 12 can be increased, the transmission loss of the photovoltaic welding tape 20 on the backlight surface 12 can be reduced, and the output power of the photovoltaic module can be improved.
[0048] This application also provides a photovoltaic module, including the solar cell string in any of the above embodiments.
[0049] For the above photovoltaic module, since each photovoltaic welding tape 20 includes a front main welding tape section and a back main welding tape section 22, the front grid line of one solar cell 10 is electrically connected to another adjacent solar cell 10 through the front main welding tape section and the back main welding tape section 22, realizing the series connection of two adjacent solar cells 10. Since at least one photovoltaic welding tape 20 further includes an auxiliary welding tape section 23, and the auxiliary welding tape section 23 is arranged on the backlight surface 12 and is conducted with the back main welding tape section 22 to increase the number of photovoltaic welding tapes 20 on the backlight surface 12 and correspondingly increase the cross-sectional area of the photovoltaic welding tapes 20 on the backlight surface 12. In this way, the transmission loss of the photovoltaic welding tapes 20 on the backlight surface 12 can be reduced, and the output power of the photovoltaic module can be improved. In addition, since the auxiliary welding tape section 23 is not provided on the light-receiving surface of the solar cell 10, that is, the number of photovoltaic welding tapes 20 on the light-receiving surface is not increased, this can avoid the light-receiving surface of the solar cell 10 from being blocked and avoid optical losses.
[0050] In the description of the present application, it should be understood that if terms such as "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" appear, the orientation or positional relationship indicated by these terms is based on the orientation or positional relationship shown in the drawings. These are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation on the present application.
[0051] In addition, if terms such as "first" and "second" appear, these terms are only for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In the description of the present application, if the term "plurality" appears, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise specifically defined.
[0052] In the present application, unless otherwise clearly specified and limited, if terms such as "mounted", "connected", "connected to", "fixed" appear, these terms should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements or the interaction relationship between two elements, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.
[0053] In the present application, unless otherwise clearly specified and limited, if there is a description such as a first feature being "on" or "under" a second feature, the meaning may be that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on top of" the second feature may mean that the first feature is directly above or obliquely above the second feature, or merely indicates that the first feature has a higher horizontal height than the second feature. The first feature being "under", "beneath" and "underneath" the second feature may be that the first feature is directly below or obliquely below the second feature, or merely indicates that the first feature has a lower horizontal height than the second feature.
[0054] It should be noted that if an element is referred to as "fixed to" or "disposed on" another element, it can be directly on the other element or there may be an intermediate element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intermediate element at the same time. If any, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are only for the purpose of illustration and do not represent the only implementation.
[0055] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.
[0056] The above-described embodiments only represent several implementation manners of this application. The description is relatively specific and detailed, but it should not be understood as a limitation on the scope of the patent application. It should be noted that for those of ordinary skill in the art, without departing from the concept of this application, several deformations and improvements can still be made, and these all belong to the protection scope of this application. Therefore, the protection scope of the patent of this application should be subject to the appended claims.
Claims
1. A solar cell string, characterized in that, Including: Solar cells (10), at least two of the solar cells (10) are provided, each of the solar cells (10) has a light-receiving surface and a backlight surface (12), the light-receiving surface is provided with front grid lines, and the backlight surface (12) is provided with back grid lines; and Photovoltaic welding tapes (20), a plurality of the photovoltaic welding tapes (20) are provided, each of the photovoltaic welding tapes (20) includes a front main welding tape section and a back main welding tape section (22), the front main welding tape section is arranged on the light-receiving surface of one of the solar cells (10), and the front main welding tape section is connected to the front grid lines, the back main welding tape section (22) is arranged on the backlight surface (12) of another adjacent solar cell (10), and the back main welding tape section (22) is electrically connected to the back grid lines, the front main welding tape section is connected to the back main welding tape section (22); at least one of the photovoltaic welding tapes (20) further includes an auxiliary welding tape section (23), the auxiliary welding tape section (23) is arranged on the backlight surface (12), and the auxiliary welding tape section (23) is electrically connected to the back main welding tape section (22).
2. The solar cell string according to claim 1, wherein The auxiliary welding tape section (23) is arranged in parallel with the back main welding tape section (22), and the outer peripheral surface of the auxiliary welding tape section (23) is in contact with the outer peripheral surface of the back main welding tape section (22).
3. The solar cell string according to claim 1, wherein, The at least one photovoltaic welding tape (20) further includes one auxiliary welding tape section (23) and a first bent welding tape section (24), the auxiliary welding tape section (23) is arranged in parallel with the back main welding tape section (22); one end of the first bent welding tape section (24) is connected to the end of the back main welding tape section (22) away from the front main welding tape section, and the other end of the first bent welding tape section (24) is connected to the auxiliary welding tape section (23).
4. The solar cell string according to claim 1, wherein, The at least one photovoltaic welding tape (20) further includes a first bent welding tape section (24), a second bent welding tape section (25) and at least two auxiliary welding tape sections (23), all the auxiliary welding tape sections (23) are arranged in parallel with the back main welding tape section (22); one end of the first bent welding tape section (24) is connected to the end of the back main welding tape section (22) away from the front main welding tape section, the other end of the first bent welding tape section (24) is connected to the auxiliary welding tape section (23) adjacent to the back main welding tape section (22), both ends of the second bent welding tape section (25) are respectively connected to the ends of two adjacent auxiliary welding tape sections (23), and the back main welding tape section (22), the first bent welding tape section (24), the auxiliary welding tape section (23) and the second bent welding tape section (25) are connected to form a meandering structure.
5. The solar cell string according to any one of claims 1 to 4, characterized in that, The front grid lines include front main grid lines and front sub-grid lines. The front main grid lines extend along a first direction, and the front sub-grid lines extend along a second direction. The front main solder ribbon segments are respectively disposed on the front main grid lines; the back grid lines include back main grid lines and back sub-grid lines. The back main grid lines extend along the first direction, and the back sub-grid lines extend along the second direction. The back main solder ribbon segments (22) are respectively disposed on the back main grid lines, and the auxiliary solder ribbon segments (23) are connected to the back sub-grid lines; wherein, the first direction is perpendicular to the second direction. Alternatively, the front grid lines include front sub-grid lines. The front sub-grid lines extend along the second direction or the front sub-grid lines are in a grid shape. The front main solder ribbon segments extend along the first direction, and the front main solder ribbon segments are connected to the front sub-grid lines; the back grid lines include back sub-grid lines. The back sub-grid lines extend along the second direction or the back sub-grid lines are in a grid shape. The back main solder ribbon segments (22) extend along the first direction, and the back main solder ribbon segments (22) and the auxiliary solder ribbon segments (23) are connected to the back sub-grid lines.
6. The solar cell string according to any one of claims 1 to 4, characterized in that, The number of the auxiliary solder ribbon segments (23) is an integer multiple of the number of the front main solder ribbon segments and the back main solder ribbon segments (22).
7. The solar cell string according to any one of claims 1 to 4, characterized in that, The front main solder ribbon segments and the back main solder ribbon segments (22) are of a continuous integral structure.
8. The solar cell string according to any one of claims 1 to 4, characterized in that, The front main solder ribbon segments, the back main solder ribbon segments (22), and the auxiliary solder ribbon segments (23) have equal diameters.
9. The solar cell string according to any one of claims 1 to 4, characterized in that, The cross-sectional shapes of the front main solder ribbon segments, the back main solder ribbon segments (22), and the auxiliary solder ribbon segments (23) are circular; Alternatively, the cross-sectional shape of the front main solder ribbon segments is circular, and the cross-sectional shapes of the back main solder ribbon segments (22) and the auxiliary solder ribbon segments (23) are flat. The cross-sectional areas of the back main solder ribbon segments (22) and the auxiliary solder ribbon segments (23) are larger than the cross-sectional area of the front main solder ribbon segments.
10. A photovoltaic module, characterized in that, A solar cell string comprising any one of claims 1 to 9.