Special-shaped conductive member and photovoltaic module

Abstract

The application discloses a special-shaped conductive piece and a photovoltaic module, and relates to the technical field of photovoltaic modules. The special-shaped conductive piece comprises a first branch connecting part, a second branch connecting part and a third branch connecting part which are connected with each other; the first branch connecting part is used for connecting a first metal electrode of a first end part cell piece close to a second cell string in a first cell string of the photovoltaic module; the second cell string is arranged in the extension direction of the first cell string; the third branch connecting part is used for connecting a second metal electrode of a second end part cell piece close to the first cell string in the second cell string of the photovoltaic module; the second branch connecting part is used for connecting a middle busbar of the photovoltaic module; and the middle busbar is arranged on the back surface of the first end part cell piece. The embodiment can shorten the transmission distance of the output current of the two cell strings, reduce the circuit transmission loss, and enhance the performance of the photovoltaic module provided with the special-shaped conductive piece.

Description

Technical Field

[0001] This invention relates to the field of photovoltaic module technology, and in particular to an irregularly shaped conductive component and a photovoltaic module. Background Technology

[0002] In the manufacturing process of photovoltaic modules, multiple cell strings are connected in series and parallel to form a cell array, which is then packaged and assembled to form a photovoltaic module. Currently, the main method is to lay conductive components on the electrode grid lines of the cell cells within the cell string. The conductive components extend outward from one end of the cell string and connect to the busbars of adjacent cell strings, thereby achieving series and parallel connections between cell strings. However, the busbars used to collect the output current of the series and parallel cell strings need to be placed adjacent to the cell strings, increasing the ineffective power generation area of ​​the cell array.

[0003] To reduce the ineffective power generation area of ​​battery arrays, existing improvements involve placing the busbars on the back of the end cells of the battery strings. For parallel battery strings, this arrangement requires bending the conductive elements to connect them to the busbars on the back of the end cells. In this structure, the output current of both parallel battery strings must flow into the busbar through the same conductive element; that is, the current of both battery strings must pass through the portion of the conductive element corresponding to the end cell with the busbar on its back before reaching the busbar. This results in battery strings with edge cells not having busbars on their backs requiring their output current to pass through the portion of the conductive element corresponding to the end cell of the other battery string before reaching the busbar. This leads to a longer current transmission distance, exacerbating circuit transmission losses and wasting energy. Summary of the Invention

[0004] In view of this, embodiments of the present invention provide an irregularly shaped conductive component and a photovoltaic module. By providing an irregularly shaped conductive component including a first branch connection portion, a second branch connection portion, and a third branch connection portion, the distance from which the output current of the first battery string and the output current of the second battery string in the photovoltaic module are transmitted to the central busbar is only the distance between the connection point of the three branch connection portions in the second branch connection portion and the part connected to the central busbar. This shortens the transmission distance of the output current of the two battery strings, thereby reducing circuit transmission loss.

[0005] To achieve the above objectives, according to one aspect of the present invention, an irregularly shaped conductive component is provided for use in a photovoltaic module, comprising: The first branch connecting part, the second branch connecting part, and the third branch connecting part are interconnected; The first branch connection portion is used to connect the first metal electrode of the first end cell of the first cell string of the photovoltaic module near the first end of the second cell string; wherein the second cell string is arranged in the extending direction of the first cell string; The aforementioned third branch connection is used to connect the second metal electrode of the second cell in the second cell string of the photovoltaic module, which is close to the second end cell of the first cell string; The second branch connection is used to connect the central busbar of the photovoltaic module; the central busbar is disposed on the back side of the first end cell.

[0006] Optionally, the first conductive segment in the first branch connection portion connected to the first metal electrode is parallel to the second conductive segment in the second branch connection portion connected to the middle busbar, and the projections of the first conductive segment and the second conductive segment on the middle busbar do not overlap.

[0007] Optionally, the length of the first conductive segment is less than or equal to the length of the first metal electrode. The length of the second conductive segment is less than or equal to the width of the middle busbar. The length of the third conductive segment in the third branch connection that is connected to the second metal electrode is less than or equal to the length of the second metal electrode.

[0008] Optionally, the second conductive segment can be a strip structure or a columnar structure.

[0009] Optionally, the length from the connection point between the second branch connection portion and the other two branch connection portions to the second conductive segment is 1mm-2mm.

[0010] Optionally, the orthographic projection of the third branch connection on the horizontal plane is located in the extension direction of the orthographic projection of the first branch connection on the horizontal plane.

[0011] To achieve the above objectives, according to another aspect of the present invention, a photovoltaic module is provided, comprising: a cover plate, a back sheet, a cell array, and an encapsulating film, wherein the encapsulating film encapsulates the cell array between the cover plate and the back sheet. The aforementioned battery array includes: a first battery string, a second battery string arranged in the extending direction of the first battery string, an irregularly shaped conductive element for electrically connecting the first battery string and the second battery string, a central bus bar, and an electrical isolation element; The aforementioned central busbar is disposed on the back side of the first end cell of the first battery string near the first end of the second battery string; The aforementioned electrical isolation element is disposed between the aforementioned middle busbar and the aforementioned first end battery cell; The aforementioned irregularly shaped conductive component includes: a first branch connection portion, a second branch connection portion, and a third branch connection portion that are interconnected; The aforementioned first branch connection portion is connected to the first metal electrode of the aforementioned first end battery cell; The aforementioned second branch connector connects to the aforementioned central busbar; The third branch connection is connected to the second metal electrode of the battery cell at the second end of the second battery string, which is close to the second end of the first battery string.

[0012] Optionally, the second metal electrode has the same polarity as the first metal electrode.

[0013] Optionally, the metal electrodes with opposite polarities included in the first end battery cell are located on the back side of the first end battery cell, and the metal electrodes with opposite polarities included in the second end battery cell are located on the back side of the second end battery cell. Optionally, the first metal electrode of the first end battery cell is located on the front side of the first end battery cell, and the second metal electrode of the second end battery cell is located on the front side of the second end battery cell.

[0014] Optionally, the edges of the first end battery cell and the second end battery cell overlap, with the edge of the first end battery cell located above the edge of the second end battery cell.

[0015] Optionally, the second branch connection is located on the side of the middle busbar near the first end cell.

[0016] Optionally, the second branch connection is located on the side of the middle busbar away from the first end battery cell.

[0017] One embodiment of the above invention has the following advantages or beneficial effects: by providing interconnected first branch connection portions, second branch connection portions, and third branch connection portions in the irregularly shaped conductive component applied to a photovoltaic module, wherein the first branch connection portion is used to connect the first metal electrode of the first end cell of the first cell string of the photovoltaic module near the first end cell of the second cell string, the second cell string is arranged in the extending direction of the first cell string, the third branch connection portion is used to connect the second metal electrode of the second end cell of the second cell string of the photovoltaic module near the second end cell of the first cell string, and the second branch connection portion is used to connect the middle busbar of the photovoltaic module, the middle busbar is disposed on the back side of the first end cell, so that the current of the first cell string can flow into the middle busbar through the first branch connection portion and the second branch connection portion of the irregularly shaped conductive component, and the current of the second cell string can flow into the middle busbar through the third branch connection portion and the second branch connection portion of the irregularly shaped conductive component. The first branch connection only needs to carry the current transmission of the first battery string, and the third branch connection only needs to carry the current transmission of the second battery string. The distance from which the output current of the two battery strings is transmitted to the central busbar is only the distance from the connection point of the three branch connections in the second branch connection to the part that connects to the central busbar. This shortens the transmission distance of the output current of the two battery strings, reduces circuit transmission loss, and improves the performance of photovoltaic modules using the aforementioned irregularly shaped conductive parts.

[0018] The further effects of the aforementioned unconventional alternative methods will be explained below in conjunction with specific implementation methods. Attached Figure Description

[0019] The accompanying drawings are provided to better understand the invention and are not intended to unduly limit the scope of the invention. Wherein: Figure 1 It is a schematic diagram based on the existing technology of two parallel battery strings with their end cells close to each other, as well as conductive components and busbars; Figure 2 This is a schematic diagram of a first structure of an irregularly shaped conductive component according to an embodiment of the present invention; Figure 3 This is a schematic diagram of a second structure of an irregularly shaped conductive component according to an embodiment of the present invention; Figure 4 This is a schematic diagram of a third structure of an irregularly shaped conductive component according to an embodiment of the present invention; Figure 5 This is a perspective view of the first and second battery strings connected in parallel via irregularly shaped conductive components according to an embodiment of the present invention. Figure 6 This is a cross-sectional view of a first structure when the first end battery cell and the second end battery cell are connected in parallel through an irregularly shaped conductive element according to an embodiment of the present invention. Figure 7 This is a schematic diagram of the connection segment of the irregularly shaped conductive component with the first structure shown in the embodiment of the present invention; Figure 8 This is a schematic diagram of the structure of a photovoltaic module according to an embodiment of the present invention; Figure 9 This is a cross-sectional view of a second structure when the first and second end battery cells are connected in parallel via an irregularly shaped conductive element according to an embodiment of the present invention. Figure 10 This is a cross-sectional view of a third structure when the first and second end battery cells are connected in parallel through an irregularly shaped conductive element according to an embodiment of the present invention. Figure 11 This is a cross-sectional view of a fourth structure when the first and second end battery cells are connected in parallel via an irregularly shaped conductive element according to an embodiment of the present invention.

[0020] Figure label: 1-Cover plate; 2-Encapsulating film; 21-Upper encapsulating film; 22-Lower encapsulating film; 3-Battery array; 30m-First battery string; 30n-Second battery string; 31-First end battery cell; 311-First metal electrode; 32-Second end battery cell; 321-Second metal electrode; 33-Irregularly shaped conductive component; 331-First branch connection; 3311-First conductive segment; 332-Second branch connection; 3321-Second conductive segment; 333-Third branch connection; 3331-Third conductive segment; a-Connecting segment; 34-Middle busbar; 35-Electrically isolating component; 4-Back panel; 5- Existing conductive components; x - First direction; y - Second direction. Detailed Implementation

[0021] For the case of battery series and parallel connection, a structure can be adopted in which the middle busbar 34 is set on the back of the end cell of a battery series. This allows the middle busbar 34 to be hidden on the back of the cell without occupying the area of ​​the battery array 3. Compared with the battery array 3 of the same size, this structure can accommodate more cells and improve the light absorption capacity of the photovoltaic module.

[0022] For this structure, the existing conductive element 5 (i.e., the existing conductive element that differs from the irregularly shaped conductive element in the embodiments of the present invention) is located on the back of the end cell. It is necessary to extend the existing conductive element 5 to the surface of the middle busbar 34 so that the existing conductive element 5 is connected to the middle busbar 34, thereby realizing the parallel connection of the cell string. In this case, the existing conductive element 5 needs to be bent. The bending point is close to the edge of the end cell, and the bending degree at the bending position is increased due to the pressure during the lamination process, the height is increased, and even a bulge appears. This position will squeeze the encapsulating film 2, resulting in less local encapsulating film distribution and weaker buffering effect, further increasing the stress on the photovoltaic module at the bending position of the existing conductive element 5, which can easily cause cell cracking.

[0023] Specifically, one of two adjacent battery strings extending in the same direction is designated as the first battery string 30m, and the other battery string is designated as the second battery string 30n. For example... Figure 1As shown, when the middle busbar 34 is disposed on the back of the first end battery cell 31 of the first battery string 30m, it is necessary to connect the first metal electrode 311 of the first end battery cell 31 of the first battery string 30m and the second metal electrode 321 of the second end battery cell 32 of the second battery string 30n through the existing conductive member 5, so as to introduce the current of the two battery strings into the middle busbar 34. The portion of the existing conductive member 5 located on the front of the second end battery cell 32 is connected to the second metal electrode 321 of the second end battery cell 32, and the portion located on the front of the first end battery cell 31 is connected to the first metal electrode 311 of the first end battery cell 31. A portion of the first end battery cell 31 located on the side away from the second end battery cell 32 extends to the back of the first end battery cell 31 and connects to the central busbar 34 on the back of the first end battery cell 31. This causes the output current of both battery strings to flow into the central busbar 34 through the existing conductive member 5. Furthermore, when the existing conductive member 5 transmits the output current of the second battery string 30n, the output current needs to pass through the portion of the existing conductive member 5 corresponding to the first end battery cell 31 and the portion between the first end battery cell 31 and the central busbar 34 before flowing into the central busbar 34 located on the back of the first end battery cell 31. Figure 1 The portion of the existing busbar corresponding to the dashed line, i.e., the output current of the two parallel battery strings, flows into the central busbar 34 through the portion of the existing conductive member 5 corresponding to the end battery cell with the central busbar 34 on the back, and the portion between the end battery cell and the central busbar 34. Thus, the portion of the existing conductive member 5 corresponding to the end battery cell with the central busbar 34 on the back needs to carry the output current of the two parallel battery strings. Typically, the length of this portion of the existing conductive member 5 is about 92mm-94mm, which is a large current transmission distance, increasing the current carrying capacity of the existing conductive member 5. Due to the influence of the resistance of the existing conductive member 5 itself, energy loss is aggravated. At the same time, the heat dissipated by energy loss is dispersed to the end battery cell with the central busbar 34 on the back, which will cause the performance degradation of the battery cell to be accelerated, thereby affecting the overall power generation performance of the photovoltaic module.

[0024] Especially for negative-pitch cell strings, i.e., cell strings where the edges of adjacent cells overlap, this further reduces the area occupied by the cell array 3 to a certain extent. When adjacent cell strings are connected in parallel, the edge of the end cell of one cell string overlaps with the edge of the end cell of another adjacent cell string. The central busbar 34 is located on the back of the end cell of one cell string. The existing conductive element 5 on the front of the end cell is bent and passes through the overlapping position, connecting with the central busbar 34 on the back of the end cell. This further increases the thickness at the overlapping edge of the cell, which greatly increases the stress at this position and makes it more likely to cause microcracks or cell cracks in the photovoltaic module.

[0025] To address the aforementioned issues, embodiments of the present invention provide an irregularly shaped conductive component 33 and a photovoltaic module.

[0026] The following description, in conjunction with the accompanying drawings, illustrates exemplary embodiments of the present invention, including various details to aid understanding. These details should be considered merely exemplary. Therefore, those skilled in the art will recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the invention. Similarly, for clarity and brevity, descriptions of well-known functions and structures are omitted in the following description.

[0027] It should be noted that the front of the solar cell refers to the side of the photovoltaic module that faces the sunlight when it is working; correspondingly, the back of the solar cell refers to the side of the photovoltaic module that faces away from the sunlight when it is working.

[0028] It should be noted that, unless otherwise specified, the embodiments of the present invention and the technical features thereof can be combined with each other.

[0029] like Figures 2-4 As shown, this embodiment of the invention provides an irregularly shaped conductive component 33, which can be applied to photovoltaic modules, including: a first branch connection portion 331, a second branch connection portion 332 and a third branch connection portion 333 that are interconnected.

[0030] in, Figure 5 and Figure 6 As shown, the first branch connection 331 is used to connect the first metal electrode 311 of the first end cell 31 of the first cell string 30m of the photovoltaic module, which is near the first end cell 31 of the second cell string 30n; wherein the second cell string 30n is arranged in the extending direction of the first cell string 30m; the third branch connection 333 is used to connect the second metal electrode 321 of the second end cell 32 of the second cell string 30n of the photovoltaic module, which is near the second end cell 32 of the first cell string 30m; the second branch connection 332 is used to connect the middle busbar 34 of the photovoltaic module; the middle busbar 34 is disposed on the back side of the first end cell 31. The middle busbar 34 refers to a busbar disposed between two adjacent cell strings in the first direction x and collecting the current of the metal electrodes of the same polarity of the two cell strings.

[0031] The first battery string 30m and the second battery string 30n are two adjacent battery strings in the first direction x in the battery array 3 of the photovoltaic module. One of the battery strings is designated as the first battery string 30m, and the other battery string is designated as the second battery string 30n.

[0032] Specifically, both the first battery string 30m and the second battery string 30n include multiple solar cells laid out along the first direction x. Within the same battery string, adjacent solar cells are connected by a strip-shaped ordinary conductive element. The solar cell in the first battery string 30m closest to the end of the second battery string 30n is designated as the first end solar cell 31, and the solar cell in the second battery string 30n closest to the end of the first battery string 30m is designated as the second end solar cell 32. As an example, in the case of forming a first battery string 30m and a second battery string 30n with double-sided electrodes, all solar cells in the first battery string 30m and the second battery string 30n except for the end cells are connected by ordinary conductive components. One end of the ordinary conductive component is connected to the metal electrode on the front of one of the two adjacent solar cells, and the other end is connected to the metal electrode on the back of the other of the two adjacent solar cells. The polarities of the metal electrodes connected at both ends of the ordinary conductive component are opposite, so as to connect multiple solar cells laid along the first direction x in series. In the case of forming a first battery string 30m and a second battery string 30n with back-contact solar cells, all solar cells in the first battery string 30m and the second battery string 30n except for the end cells are connected by ordinary conductive components. One end of the ordinary conductive component is connected to the metal electrode on the back of one of the two adjacent solar cells with positive polarity, and the other end is connected to the metal electrode on the back of the other of the two adjacent solar cells with negative polarity.

[0033] The structure of the irregularly shaped conductive element 33 in this embodiment of the invention includes, but is not limited to, the following three types: The first structure, such as Figure 2 As shown, the first branch connecting part 331 bends downward at one end near the third branch connecting part 333 and connects to the third branch connecting part 333; the second branch connecting part 332 bends upward at one end near the third branch connecting part 333 and connects to the third branch connecting part 333. The bent sections of the first branch connecting part 331 and the second branch connecting part 332 are both arc-shaped structures.

[0034] The second structure, such as Figure 3 As shown, the first branch connecting part 331 bends downward at one end near the third branch connecting part 333 and connects to the third branch connecting part 333; the second branch connecting part 332 and the third branch connecting part 333 are in the same plane. The bent section of the first branch connecting part 331 has an arc-shaped structure.

[0035] The third structure, such as Figure 4As shown, the first branch connecting part 331 bends downward at one end near the third branch connecting part 333 and connects to the third branch connecting part 333; the second branch connecting part 332 bends upward at one end near the third branch connecting part 333 and connects to the third branch connecting part 333. The bent sections of the first branch connecting part 331 and the second branch connecting part 332 are both polygonal structures with bend vertices.

[0036] In one alternative embodiment, such as Figure 5 and Figure 6 As shown, the first conductive segment 3311 in the first branch connection 331 that is connected to the first metal electrode 311 is parallel to the second conductive segment 3321 in the second branch connection 332 that is connected to the middle busbar 34, and the projections of the first conductive segment 3311 and the second conductive segment 3321 on the middle busbar 34 do not overlap.

[0037] By setting the projections of the first conductive segment 3311 and the second conductive segment 3321 onto the middle busbar 34 to be non-overlapping, and staggering them in the second direction y, the thickness of the photovoltaic module is reduced, which can reduce stress and lower the probability of microcracks and cracks in the photovoltaic module.

[0038] Preferably, the length of the first conductive segment 3311 is less than or equal to the length of the first metal electrode 311. Generally, the length of the first metal electrode 311 in the first end battery cell 31 is less than the width of the first end battery cell 31. In order to reduce its manufacturing cost while maintaining the performance of the irregularly shaped conductive component 33, the length of the first conductive segment 3311 can be set to be less than or equal to the length of the first metal electrode 311, so that the first conductive segment 3311 can completely or partially cover the first metal electrode 311 in the length direction. Similarly, the length of the third conductive segment 3331 in the third branch connection portion 333 that is connected to the second metal electrode 321 is less than or equal to the length of the second metal electrode 321.

[0039] The length of the second conductive segment 3321 is less than or equal to the width of the middle busbar 34.

[0040] Preferably, the length of the second conductive segment 3321 is equal to the width of the central busbar 34. The current with the same polarity as the first metal electrode 311 in the first battery string 30m and the current with the same polarity as the second metal electrode 321 in the second battery string 30n both flow into the central busbar 34 via the second branch connection 332. By setting the length of the second conductive segment 3321 to be less than or equal to the width of the central busbar 34, the second conductive segment 3321 can be completely fitted to the central busbar 34. This reduces the manufacturing cost of the irregularly shaped conductive component 33 while increasing the contact area between the second conductive segment 3321 and the central busbar 34, thereby improving the current transmission performance of the irregularly shaped conductive component 33.

[0041] In an optional embodiment, the second conductive segment 3321 can be a strip structure or a column structure. When the second conductive segment 3321 is a flat strip structure, its application to photovoltaic modules can reduce the thickness of the photovoltaic modules, lowering the risk of microcracks in the cells due to stress concentration at that location. Simultaneously, it increases the contact area between the second conductive segment 3321 and the central busbar 34, thereby enhancing the ability of the irregularly shaped conductive element 33 to conduct current to the central busbar 34 and improving welding reliability.

[0042] Optionally, the cross-section of the second conductive segment 3321 of the columnar structure can be circular, elliptical, square, etc., but is generally circular.

[0043] Preferably, the second branch connection portion 332 is a strip structure. Especially when the above-mentioned irregular conductive component 33 is applied to a negative-pitch battery string, that is, in a battery string structure where the edges of the first end battery piece 31 and the second end battery piece 32 are close to each other and overlap, the entire second branch connection portion 332 is a flat structure, which can further reduce the thickness at the overlapping position and reduce the stress at that position.

[0044] In addition, such as Figure 7 As shown, the connecting segment a of the first branch connection portion 331, the second branch connection portion 332, and the third branch connection portion 333 in the irregularly shaped conductive component 33 can also be configured as a strip structure or a column structure. Here, connecting segment a refers to the portion of the irregularly shaped conductive component 33 corresponding to the connection area of ​​the first branch connection portion 331, the second branch connection portion 332, and the third branch connection portion 333, including the end of the first branch connection portion 331 near the third branch connection portion 333, the end of the second branch connection portion 332 near the third branch connection portion 333, and the end of the third branch connection portion 333 near the first branch connection portion 331. In the connecting segment a where the three components connect, the irregularly shaped conductive component 33 has the greatest thickness. To reduce the impact of this connecting segment a on the thickness of the photovoltaic module, and to further reduce the thickness at the overlapping position in the case of negative-pitch cell strings, the connecting segment a can be configured as a strip structure.

[0045] In an optional embodiment, the length of the second branch connection portion 332 from its connection point with the first branch connection portion 331 and the third branch connection portion 333 to the second conductive segment 3321 is 1mm-2mm. Here, the connection point refers to the connection position of the three branch connection portions. The current of the first battery string 30m collected by the first conductive segment 3311 of the first branch connection 331 and the current of the second battery string 30n collected by the third conductive segment 3331 of the third branch connection 333 can be transmitted to the central busbar 34 through the part between the connection point and the second conductive segment 3321 (the part connected to the central busbar 34) in the irregular conductive member 33. The distance of the output current of the two battery strings to the central busbar 34 is only the distance between the connection point and the second conductive segment 3321. Compared with the traditional solution where the output current of the two parallel battery strings must pass through the part of the existing conductive member 5 on the back corresponding to the end battery piece on the back where the busbar is provided, the transmission distance of the output current of the two battery strings is greatly shortened, and the current carrying pressure of the irregular conductive member and the circuit transmission loss are reduced.

[0046] In an optional embodiment, the orthographic projection of the third branch connection portion 333 on the horizontal plane is located in the extension direction of the orthographic projection of the first branch connection portion 331 on the horizontal plane.

[0047] In order to better connect the first battery string 30m and the second battery string 30n in parallel, the first metal electrode 311 in the first end battery cell 31 and the second metal electrode 321 in the second end battery cell 32 are respectively arranged so that the first branch connection part 331 and the first metal electrode 311 form good contact, and the third branch connection part 333 and the second metal electrode 321 form good contact, which facilitates the collection and discharge of current using the irregularly shaped conductive part 33.

[0048] In the fabrication process of the irregularly shaped conductive component 33, an integrally formed elongated ordinary conductive component can be used, and a second branch connection portion 332 is welded to the middle section of the ordinary conductive component in the length direction. This causes the connection point of the ordinary conductive component at the welding position to extend to both sides in the length direction, forming a first branch connection portion 331 and a third branch connection portion 333, which, together with the second branch connection portion 332 welded to the side of the middle section, constitute the irregularly shaped conductive component 33. When the irregularly shaped conductive component 33 is used, the first branch connection portion 331 covers the first metal electrode 311 of the first end battery cell 31, and the third branch connection portion 333 covers the second metal electrode 321 of the second end battery cell 32, such that the orthographic projection of the third branch connection portion 333 on the horizontal plane is located in the extension direction of the orthographic projection of the first branch connection portion 331 on the horizontal plane. Through this arrangement, the irregularly shaped conductive component 33 of this embodiment can be directly fabricated using an elongated ordinary conductive component, simplifying the fabrication process of the irregularly shaped conductive component 33.

[0049] Specifically, when the edges of the first end battery piece 31 of the first battery string 30m and the second end battery piece 32 of the second battery string 30n overlap, after the first conductive segment 3311 of the first branch connection portion 331 and the first metal electrode 311 are connected, the part of the first branch connection portion 331 other than the first conductive segment 3311 (i.e. the end of the first branch connection portion 331 near the third branch connection portion 333) can be bent toward the direction of the second end battery piece 32 so that the second metal electrode 321 can be covered by the third branch connection portion 333.

[0050] According to an embodiment of the present invention, the irregularly shaped conductive component 33 applied to a photovoltaic module is provided with interconnected first branch connection portion 331, second branch connection portion 332, and third branch connection portion 333. The first branch connection portion 331 is used to connect the first metal electrode 311 of the first end cell 31 of the first cell string 30m of the photovoltaic module near the first end cell 31 of the second cell string 30n. The second cell string 30n is arranged in the extending direction of the first cell string 30m. The third branch connection portion 333 is used to connect the second cell string 30n of the photovoltaic module... The second metal electrode 321 near the second end cell 32 of the first cell string 30m and the second branch connection 332 are used to connect the middle busbar 34 of the photovoltaic module. The middle busbar 34 is disposed on the back of the first end cell 31 so that the current of the first cell string 30m can flow into the middle busbar 34 through the first branch connection 331 and the second branch connection 332 of the irregular conductive member, and the current of the second cell string 30n can flow into the middle busbar 34 through the third branch connection 333 and the second branch connection 332 of the irregular conductive member 33. The first branch connection 331 only needs to carry the current transmission of the first battery string 30m, and the third branch connection 333 only needs to carry the current transmission of the second battery string 30n. The distance from which the output current of the two battery strings is transmitted to the central busbar 34 is only the distance from the connection point of the three branch connections in the second branch connection 332 to the part that connects to the central busbar 34. This shortens the transmission distance of the output current of the two battery strings, reduces circuit transmission loss, and improves the performance of the photovoltaic module using the aforementioned irregular conductive component 34.

[0051] Figure 8 This is a schematic diagram of the structure of a photovoltaic module according to an embodiment of the present invention. Figure 8 As shown, the photovoltaic module of this embodiment mainly includes: a cover plate 1, a back sheet 4, a cell array 3, and an encapsulating film 2.

[0052] The cover plate 1 can be made of tempered glass with an anti-reflective coating on its surface. It is mainly used to isolate the internal structure of the photovoltaic module from the outside world, improve the reliability and weather resistance of the photovoltaic module, and at the same time has high light transmittance, so that sunlight can be incident on the front of the cell of the battery array 3, thereby improving the power generation of the photovoltaic module.

[0053] The encapsulating film 2 encapsulates the battery array 3 between the cover plate 1 and the back plate 4, and mainly includes an upper encapsulating film 21 and a lower encapsulating film 22. The upper encapsulating film 21 is mainly disposed between the cover plate 1 and the battery array 3, and the lower encapsulating film 22 is mainly disposed between the battery array 3 and the back plate 4.

[0054] The encapsulating film 2 can be prepared using ethylene-vinyl acetate copolymer (EVA), polyolefin elastomer (POE), or EPE (EVA-POE-EVE three-layer co-extrusion). It is mainly used for insulation between the battery array 3 and the outside world, sealing and buffering of the battery array 3, preventing moisture and dust from entering the photovoltaic module, and reducing the probability of microcracks and fragments in the battery cells.

[0055] The backsheet 4 can be made of a TPT multilayer composite film composed of polyvinyl fluoride (PVF), biaxially oriented polyethylene terephthalate film (BOPET), and PVF. It is mainly used to isolate the internal structure of the photovoltaic module from the outside world, and has the functions of insulation, mechanical protection and improving weather resistance.

[0056] The battery array 3, as the core structure of the photovoltaic module, is mainly used to convert solar energy into electrical energy. It includes: a first battery string 30m, a second battery string 30n arranged along the extending direction of the first battery string 30m, a shaped conductive element 33 for electrically connecting the first battery string 30m and the second battery string 30n, a central busbar 34, and an electrical isolation element 35. The shaped conductive element 33 is the same as any one of the shaped conductive elements described in the above embodiments of the present invention.

[0057] like Figure 5 As shown, the first battery string 30m and the second battery string 30n are connected in parallel via a shaped conductive element 33. The aforementioned central busbar 34 is disposed on the back side of the first battery string 30m near the first end battery cell 31 of the second battery string 30n.

[0058] like Figure 6 , Figures 9-11 As shown, the aforementioned electrical isolation element 35 is made of insulating material and is disposed between the central busbar 34 and the first end battery cell 31 to isolate the central busbar 34 and the first end battery cell 31. This prevents the metal electrode on the back of the first end battery cell 31, which has a conductivity type opposite to that of the irregularly shaped conductive element 33, from contacting the central busbar 34, thus avoiding short circuits or leakage. Furthermore, the aforementioned electrical isolation element 35 can be made of an insulating material with a certain degree of elasticity, such as EVA, POE, or silicone, to achieve isolation while buffering the stress between the first end battery cell 31 and the electrical isolation element 35.

[0059] The second metal electrode 321 has the same polarity as the first metal electrode 311. When the first metal electrode 311 of the first end battery cell 31 connected to the irregularly shaped conductive component 33 is the positive electrode, the second metal electrode 321 of the second end battery cell 32 connected to it is also the positive electrode; when the first metal electrode of the first end battery cell 31 connected to the irregularly shaped conductive component 33 is the negative electrode, the second metal electrode 321 of the second end battery cell 32 connected to it is also the negative electrode.

[0060] The first metal electrode 311 and the second metal electrode 321 can be either main grid lines or fine grid lines. When the first metal electrode 311 and the second metal electrode 321 are fine grid lines, the first end cell 31 and the second end cell 32 can be gridless cells, that is, solar cells that do not have main grids, only fine grids, and collect current through the fine grids and conductive parts welded to them.

[0061] The irregularly shaped conductive component 33 has three branch connection parts that connect to the first metal electrode 311, the second metal electrode 321, and the central busbar 34 respectively. This eliminates the need to bend the irregularly shaped conductive component 33, reducing the risk of increased stress due to increased height at the bending position. At the same time, it can eliminate the problem of microcracks or cracks in the battery cell caused by the reduction of the surrounding encapsulating film 2 due to compression at the bending position during the lamination process, resulting in poor buffering capacity.

[0062] In an optional embodiment, the edges of the first end cell 31 and the second end cell 32 overlap, with the edge of the first end cell 31 located above the edge of the second end cell 32. Specifically, the edges of adjacent cells in the first cell string 30m and the second cell string 30n overlap, and the first cell string 30m and the second cell string 30n are connected with negative spacing. In this case, the edges of the first end cell 31 and the second end cell 32 overlap, thereby further reducing the area of ​​the cell array 3, eliminating gaps between cells and between strings, and thus improving the effective light-receiving area and area utilization of the photovoltaic module.

[0063] In response to the overlapping structure of the first end battery cell 31 and the second end battery cell 32, at least a portion of the second branch connection portion 332 and the middle busbar 34 are disposed on the back side of the first end battery cell 31, which can support the first end battery cell 31, share the pressure on the edge of the second end battery cell 32, and further reduce the possibility of battery cell cracking.

[0064] Preferably, the connection point of the three branch connections in the irregularly shaped conductive component 33 can be located above or below the second end battery piece 32. Since the edges of the first end battery piece 31 and the second end battery piece 32 overlap, there is a certain height difference between the upper surfaces of the first end battery piece 31 and the second end battery piece 32. In the case where the first metal electrode 311 is located on the front of the first end battery piece 31 and the second metal electrode 321 is located on the front of the second end battery piece 32, when the connection point is located above the second end battery piece 32, the connecting segment a of the irregularly shaped conductive component 33 is supported by the corner of the first end battery piece 31 and the upper surface of the second end battery piece 32, allowing the bending... The portion distributed in the irregularly shaped conductive component 33 corresponding to the section between the first end battery cell 31 and the second end battery cell 32 has a larger bending radius and a smaller degree of bending compared to the bending section formed by only the corner of the first end battery cell as support in the traditional solution. The bending radius is larger, the curvature is reduced, and the degree of bending is reduced, resulting in a smoother bending section. The stress experienced during the lamination process is reduced, avoiding problems such as increased bending degree and bulging caused by lamination. This can reduce the compression of the encapsulation film 2 at this position, thereby reducing the risk of battery cell cracking.

[0065] In addition, the first end battery cell 31 and the second end battery cell 32 may also have a gap in the first direction x, that is, the first battery string 30m and the second battery string 30n are connected with a non-negative gap.

[0066] Optionally, for structures where the edges of the first end battery cell 31 and the second end battery cell 32 overlap or have gaps, the electrical isolation member 35 can extend to the overlapping area and the gap area to achieve better electrical isolation and provide a certain buffering effect, reducing the probability of microcracks in the battery cell.

[0067] In one optional embodiment, the metal electrodes with opposite polarities included in the first end battery cell 31 are located on the back side of the first end battery cell 31, and the metal electrodes with opposite polarities included in the second end battery cell 32 are located on the back side of the second end battery cell 32; or, the first metal electrode 311 included in the first end battery cell 31 is located on the front side of the first end battery cell 31, and the second metal electrode 321 included in the second end battery cell 32 is located on the front side of the second end battery cell 32.

[0068] The first metal electrode 311 can be located on the front or back of the first end battery cell 31, and the second metal electrode 321 can be located on the front or back of the second end battery cell 32. The first metal electrode 311 and the second metal electrode 321 are respectively disposed on the same side of their respective end battery cells.

[0069] For the first end cell 31, in addition to the first metal electrode 311 described above, it also includes a metal electrode with the opposite polarity to the first metal electrode 311. Both the first metal electrode 311 and the metal electrode with the opposite polarity can be disposed on the back side of the first end cell 31, meaning the first end cell 31 can be a back-contact solar cell. Alternatively, the first metal electrode 311 and the metal electrode with the opposite polarity can be disposed on opposite sides of the first end cell 31. Specifically, when the first metal electrode 311 is located on the front side of the first end cell 31, the metal electrode with the opposite polarity is disposed on the back side of the first end cell 31; when the first metal electrode 311 is located on the back side of the first end cell 31, the metal electrode with the opposite polarity is disposed on the front side of the first end cell 31, making the first end cell 31 a bifacial electrode solar cell. Similarly, the second end cell 32 follows the same principle and will not be described further here.

[0070] In one alternative embodiment, such as Figure 6 and Figure 10 As shown, the second branch connection 332 is located on the side of the middle busbar 34 near the first end battery cell 31, such that the electrical isolation member 35 and the second branch connection 332 are located between the first end battery cell 31 and the middle busbar 34 to avoid short circuit.

[0071] In addition, such as Figure 9 and Figure 11 As shown, the second branch connection 332 can also be located on the side of the central busbar 34 away from the first end battery cell 31, so that the electrical isolation member 35 and the second branch connection 332 are respectively disposed on both sides of the central busbar 34. By setting the second branch connection 332 on the side of the central busbar 34 away from the first end battery cell 31, short circuits are avoided, and it is also convenient for technicians to inspect and repair poor contact welds after the central busbar 34 and the second branch connection 332 are welded.

[0072] It should be noted that, Figure 5 The structure of a first battery string 30m and a second battery string 30n formed by bifacial electrode solar cells is shown, with the first battery string 30m and the second battery string 30n arranged with a negative spacing. The structure shown is merely exemplary, including a first battery string 30m and a second battery string 30n containing three solar cells. In reality, the first battery string 30m and the second battery string 30n may include any number of solar cells (more than two). No specific limitation is made on the number of solar cells in the first battery string 30m and the second battery string 30n. Additionally, to demonstrate the structure and relative position of the central busbar 34 and the irregularly shaped conductive element 33... Figure 5 The electrical isolation element 35 disposed between the middle busbar 34 and the first end cell 31, as well as the ordinary conductive element for connecting adjacent solar cells in the series battery string, are not shown.

[0073] In summary, the specific structure of the photovoltaic module provided in the embodiments of the present invention may include, but is not limited to, the following four examples. Each example of the photovoltaic module structure includes a cover plate 1, a backplate 4, a cell array 3, and an encapsulating film 2. The encapsulating film 2 encapsulates the cell array 3 between the cover plate 1 and the backplate 4. The cell array 3 includes: a first cell string 30m, a second cell string 30n arranged in the extending direction of the first cell string 30m, a shaped conductive member 33 for electrically connecting the first cell string 30m and the second cell string 30n, a central busbar 34, and an electrical isolation member 35. The central busbar 34 is disposed at the first end of the first cell string 30m near the first end of the second cell string 30n. The back side of the solar cell 31; the aforementioned electrical isolation member 35 is disposed between the aforementioned central busbar 34 and the aforementioned first end solar cell 31; the aforementioned irregularly shaped conductive member 33 includes: a first branch connection portion 331, a second branch connection portion 332, and a third branch connection portion 333 interconnected with each other; the aforementioned first branch connection portion 331 connects to the first metal electrode 311 of the aforementioned first end solar cell 31; the aforementioned second branch connection portion 332 connects to the aforementioned central busbar 34; the aforementioned third branch connection portion 333 connects to the second metal electrode 321 of the second end solar cell 32 in the aforementioned second solar cell string 30n near the aforementioned first solar cell string 30m, the aforementioned second metal electrode 321 having the same polarity as the aforementioned first metal electrode 311. The specific structures of the photovoltaic modules in the four examples are described in detail below: First example, such as Figure 6 As shown, the first battery string 30m and the second battery string 30n are connected with a negative spacing, and the battery cells in them are all bifacial solar cells. The edges of the first end battery cell 31 and the second end battery cell 32 overlap. The first metal electrode 311 is located on the front side of the first end battery cell 31, and the second metal electrode 321 is located on the front side of the second end battery cell 32. The first branch connection portion 331 connects to the first metal electrode 311, the third branch connection portion 333 connects to the second metal electrode 321, and the second branch connection portion 332 is disposed on the side of the central busbar 34 near the first end battery cell 31. The electrical isolation member 35 and the second branch connection portion 332 are disposed between the central busbar 34 and the first end battery cell 31, and the electrical isolation member 35 extends to the overlapping area of ​​the first end battery cell 31 and the second end battery cell 32 to isolate the first end battery cell 31 and the second branch connection portion 332 passing through the overlapping area.

[0074] Second example, such as Figure 9As shown, the cells in the first battery string 30m and the second battery string 30n are both bifacial solar cells. A gap exists between the adjacent edges of the first end cell 31 and the second end cell 32. The first metal electrode 311 is located on the front side of the first end cell 31, and the second metal electrode 321 is located on the front side of the second end cell 32. A first branch connection 331 connects to the first metal electrode 311, a third branch connection 333 connects to the second metal electrode 321, and the second branch connection 332 is located on the side of the central busbar 34 away from the first end cell 31. An electrical isolation member 35 is disposed between the first end cell 31 and the central busbar 34, and extends into the gap between the first end cell 31 and the second end cell 32.

[0075] The third example, such as Figure 10 As shown, the first battery string 30m and the second battery string 30n are connected with a negative spacing. The battery cells can be either bifacial solar cells or back-contact solar cells. The edges of the first end battery cell 31 and the second end battery cell 32 overlap. The first metal electrode 311 is located on the back of the first end battery cell 31, and the second metal electrode 321 is located on the back of the second end battery cell 32. The first branch connection 331 connects to the first metal electrode 311, the third branch connection 333 connects to the second metal electrode 321, and the second branch connection 332 is disposed on the side of the central busbar 34 near the first end battery cell 31. The electrical isolation member 35, the first branch connection 331, and the second branch connection 332 are disposed between the first end battery cell 31 and the central busbar 34.

[0076] Fourth example, such as Figure 11 As shown, the first battery string 30m and the second battery string 30n are connected with a negative spacing. The battery cells can be either bifacial solar cells or back-contact solar cells. The edges of the first end battery cell 31 and the second end battery cell 32 overlap. The first metal electrode 311 is located on the back side of the first end battery cell 31, and the second metal electrode 321 is located on the back side of the second end battery cell 32. The first branch connection 331 connects to the first metal electrode 311, the third branch connection 333 connects to the second metal electrode 321, and the second branch connection 332 is located on the side of the central busbar 34 away from the first end battery cell 31. The first branch connection 331, the electrical isolation member 35, and the central busbar 34 are located between the first end battery cell 31 and the second branch connection 332.

[0077] Regarding the structure shown in the third and fourth examples, where the first metal electrode 311 is disposed on the back side of the first end battery cell 31 and the second metal electrode 321 is disposed on the back side of the second end battery cell 32, the irregularly shaped conductive element 33 and the central busbar 34 are completely hidden on the back side of the first end battery cell 31 and the second end battery cell 32. The bending degree of the section of the first branch connection 331 near the third branch connection 333 is reduced, thereby reducing the edge stress of the battery cell. Furthermore, since the metal electrode on the back side of the battery cell is not affected by the light transmission requirement, its wiring is wider and its area is larger. The welding reliability of the irregularly shaped conductive element 33 and the metal electrode disposed on the back side of the battery cell is higher, and the risk of displacement or desoldering is lower.

[0078] According to an embodiment of the photovoltaic module of the present invention, the cell array 3 includes a first cell string 30m, a second cell string 30n, an irregularly shaped conductive member 33 electrically connecting the first cell string 30m and the second cell string 30n, a central busbar 34, and an electrical isolation member 35. The central busbar 34 is disposed on the back side of the first end cell 31 of the first cell string 30m near the second cell string 30n, replacing the structure where the central busbar 34 is disposed in the gap between the first cell string 30m and the second cell string 30n. This improves the area utilization rate of the cell array 3, allowing more cells to be accommodated within the same module size, thereby increasing the effective light-receiving area and power generation efficiency of the module. The electrical isolation member 35 is disposed between the central busbar 34 and the first end cell. The isolation between the two is achieved, which can effectively avoid the occurrence of short circuits. The irregularly shaped conductive component 33 includes a first branch connection portion 331 connecting the first metal electrode 311 of the first end battery cell 31, a second branch connection portion 332 connecting the middle busbar 34, and a third branch connection portion 333 connecting the second metal electrode 321 of the second end battery cell 32 of the second battery string 30n. The irregularly shaped conductive component 33 realizes the parallel connection of the first battery string 30m and the second battery string 30n. The current of the first battery string 30m and the second battery string 30n both flow into the middle busbar 34 disposed on the back of the first end battery cell 31 through the second branch connection portion 332, which shortens the current transmission path and reduces circuit transmission loss.

[0079] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can occur depending on design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. An irregularly shaped conductive component, characterized in that, Applied to photovoltaic modules, including: The first branch connection part (331), the second branch connection part (332) and the third branch connection part (333) are interconnected. The first branch connection (331) is used to connect the first metal electrode (311) of the first end cell (31) of the first cell string (30m) of the photovoltaic module near the second cell string (30n); wherein the second cell string (30n) is arranged in the extending direction of the first cell string (30m); The third branch connection (333) is used to connect the second metal electrode (321) of the second end cell (32) of the second cell string (30n) of the photovoltaic module, which is close to the first cell string (30m). The second branch connection (332) is used to connect the central busbar (34) of the photovoltaic module; the central busbar (34) is disposed on the back of the first end cell (31).

2. The irregularly shaped conductive component according to claim 1, characterized in that, The first conductive segment (3311) in the first branch connection (331) connected to the first metal electrode (311) is parallel to the second conductive segment (3321) in the second branch connection (332) connected to the middle busbar (34), and the projections of the first conductive segment (3311) and the second conductive segment (3321) on the middle busbar (34) do not overlap.

3. The irregularly shaped conductive component according to claim 2, characterized in that, The length of the first conductive segment (3311) is less than or equal to the length of the first metal electrode (311); The length of the second conductive segment (3321) is less than or equal to the width of the central busbar (34); The length of the third conductive segment (3331) in the third branch connection (333) that is connected to the second metal electrode (321) is less than or equal to the length of the second metal electrode (321).

4. The irregularly shaped conductive component according to claim 2, characterized in that, The second conductive segment (3321) is a strip structure or a column structure; And / or, The length of the second branch connection (332) from its connection point with the first branch connection (331) and the third branch connection (333) to the second conductive segment (3321) is 1mm-2mm.

5. The irregularly shaped conductive component according to claim 1, characterized in that, The orthographic projection of the third branch connection (333) on the horizontal plane is located in the extension direction of the orthographic projection of the first branch connection (331) on the horizontal plane.

6. A photovoltaic module, comprising: The battery array comprises a cover plate (1), a back plate (4), a battery array (3), and an encapsulating film (2), wherein the encapsulating film (2) encapsulates the battery array (3) between the cover plate (1) and the back plate (4), characterized in that... The battery array (3) includes: a first battery string (30m), a second battery string (30n) arranged in the extension direction of the first battery string (30m), a shaped conductive element (33) for electrically connecting the first battery string (30m) and the second battery string (30n), a central bus bar (34), and an electrical isolation element (35). The central busbar (34) is disposed on the back of the first end battery cell (31) of the first battery string (30m) near the second battery string (30n); The electrical isolation element (35) is disposed between the middle busbar (34) and the first end battery cell (31); The irregularly shaped conductive component (33) includes: a first branch connection portion (331), a second branch connection portion (332), and a third branch connection portion (333) that are interconnected. The first branch connection (331) is connected to the first metal electrode (311) of the first end battery cell (31). The second branch connector (332) is connected to the central busbar (34); The third branch connection (333) is connected to the second metal electrode (321) of the second end battery cell (32) of the second battery string (30n) near the first battery string (30m).

7. The photovoltaic module according to claim 6, characterized in that, The first end battery cell (31) includes metal electrodes of opposite polarity located on the back side of the first end battery cell (31), and the second end battery cell (32) includes metal electrodes of opposite polarity located on the back side of the second end battery cell (32). or, The first end battery cell (31) includes a first metal electrode (311) located on the front side of the first end battery cell (31), and the second end battery cell (32) includes a second metal electrode (321) located on the front side of the second end battery cell (32).

8. The photovoltaic module according to claim 6, characterized in that, The second metal electrode (321) has the same polarity as the first metal electrode (311).

9. The photovoltaic module according to any one of claims 6 to 8, characterized in that, The edges of the first end battery piece (31) and the second end battery piece (32) overlap, with the edge of the first end battery piece (31) located above the edge of the second end battery piece (32).

10. The photovoltaic module according to any one of claims 6 to 8, characterized in that, The second branch connection (332) is located on the side of the middle busbar (34) near the first end battery cell (31); or, The second branch connection (332) is located on the side of the middle busbar (34) away from the first end battery cell (31).

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