A method of manufacturing a photovoltaic module and a photovoltaic module

Abstract

This invention discloses a method for manufacturing photovoltaic (PV) modules and a PV module itself. The method includes: fabricating multiple first back-contact solar cell strings and multiple second back-contact solar cell strings, each containing two parallel sub-cell strings, using a stringer; laying a cover plate; laying a pre-encapsulating film on the cover plate; alternately arranging the multiple first back-contact solar cell strings and multiple second back-contact solar cell strings on the pre-encapsulating film; connecting the multiple first back-contact solar cell strings and multiple second back-contact solar cell strings in series to form a cell array; laying a post-encapsulating film on the cell array; laying a backsheet on the post-encapsulating film; and laminating the components to form a laminate. This manufacturing method ensures that the spacing between the parallel cell strings in the manufactured PV module remains consistent.

Description

Technical Field

[0001] This invention relates to a method for manufacturing photovoltaic modules and a photovoltaic module. Background Technology

[0002] Currently, the back-contact solar cell strings used in the fabrication of photovoltaic modules are generally formed by connecting individual cells cut from back-contact solar cells in series. This requires the use of a layout machine to arrange and deploy the central busbar in the middle area of ​​the photovoltaic module, as well as to arrange and deploy the cell strings on both sides of the central busbar in the middle area. Then, a shingling machine is used to weld the solder strips or interconnect strips on the cell strings to the central busbar in the middle area, so that the back-contact solar cell strings located on both sides of the central busbar are connected in parallel.

[0003] On the one hand, due to the poor precision of the layout machine in controlling the spacing, the spacing between the battery strings on both sides of the intermediate busbar and the central busbar in the middle area is relatively large during the layout and deployment process, and it is difficult to maintain a consistent spacing. On the other hand, because the shingling machine needs to stagger the welding strips or interconnecting strips on the battery strings on both sides of the intermediate busbar to the intermediate busbar, a relatively wide intermediate busbar is required. Therefore, using existing back-contact solar cell strings to prepare photovoltaic modules makes it difficult to reduce the spacing between the battery strings connected in parallel through the intermediate busbar in the photovoltaic module, and it is also difficult to maintain a consistent spacing between different parallel battery strings in the photovoltaic module. Summary of the Invention

[0004] In view of this, the present invention provides a method for preparing a photovoltaic module and a photovoltaic module, which enables the spacing between the parallel battery strings in the prepared photovoltaic module to remain consistent, thereby reducing the difficulty of preparing the photovoltaic module.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0006] In a first aspect, the present invention provides a method for manufacturing a photovoltaic module, comprising:

[0007] Step (2-0): Multiple first back-contact solar cell strings and multiple second back-contact solar cell strings are fabricated using a stringer. Each first back-contact solar cell string and each second back-contact solar cell string includes two sub-cell strings arranged side-by-side along a first direction and connected in parallel by an interconnecting strip. The first direction is the length direction of the sub-cell strings.

[0008] In the first back-contact solar cell string, the first electrode of the right end cell of the left sub-cell string corresponds one-to-one with the first electrode of the left end cell of the right sub-cell string and is connected by an interconnecting wire.

[0009] In the second back-contact solar cell string, the second electrode of the right end cell of the left sub-cell string corresponds one-to-one with the second electrode of the left end cell of the right sub-cell string and is connected by an interconnecting wire.

[0010] The first electrode and the second electrode have opposite polarities;

[0011] Step (2-1): Lay the cover plate and then lay the pre-sealing film on the cover plate;

[0012] Step (2-2): Along a second direction perpendicular to the first direction, the first back-contact solar cell string and the second back-contact solar cell string are alternately laid on the front encapsulation film in the order of first back-contact solar cell string - second back-contact solar cell string ... first back-contact solar cell string - second back-contact solar cell string;

[0013] Step (2-3): Connect multiple first back-contact solar cell strings and multiple second back-contact solar cell strings in series to form a battery array;

[0014] Steps (2-4): A post-encapsulation film is laid on the battery array, a backsheet is laid on the post-encapsulation film, and a laminate is formed after lamination.

[0015] Secondly, embodiments of the present invention provide a photovoltaic module prepared according to the first aspect of the embodiments described above, comprising: the gap between the right-end cell and the left-end cell is equal to the gap between every two adjacent cells in the sub-cell string.

[0016] The technical solution of the first aspect of the above invention has the following advantages or beneficial effects:

[0017] 1. Since both the first back-contact solar cell string and the second back-contact solar cell string laid in the photovoltaic module prepared in the embodiments of the present invention contain two parallel sub-cell strings, the parallel connection process can be prepared by the string welding machine used to prepare the sub-cell strings or by using the same process conditions as the sub-cell strings. This allows the stacking stage of the photovoltaic module to omit the process of the stacking machine to arrange the parallel cell strings, thereby reducing the difficulty of photovoltaic module preparation.

[0018] 2. In the embodiments of the present invention, the back-contact solar cell string (i.e., the first back-contact solar cell string or the second back-contact solar cell string) used to prepare the photovoltaic module is treated as a whole. Compared with the process of preparing sub-cell strings, because the same stringer or the same process is used, the spacing between the two parallel sub-cell strings contained in the back-contact solar cell string can be kept consistent with the spacing between the cells in the sub-cell string. That is to say, the spacing between each cell in the entire back-contact solar cell string is equal. Compared with the prior art, which uses a layout machine to place two parallel sub-cell strings in the stacking process of photovoltaic modules, the layout process of the prior art results in a large spacing between the two parallel sub-cell strings due to the accuracy limitations of the layout machine, which is greater than the spacing between the cells in the sub-cell string. The technical solution of this application can reduce the gap between two parallel sub-cell strings, and can utilize the area of ​​the photovoltaic module more efficiently.

[0019] 3. In the prior art, the two corresponding electrodes (first electrode or second electrode) of the two cells at the ends of two parallel battery strings are first connected to different interconnecting strips, and then the electrodes are connected to the busbar after being arranged by a layout machine. Each interconnecting strip forms a solder joint with the busbar, resulting in a large number of solder joints. In contrast, the technical solution of this application connects each pair of corresponding first electrodes or each pair of corresponding second electrodes in the right end cell of one sub-cell string and the left end cell of another sub-cell string through an interconnecting strip. Then, the interconnecting strip connecting each pair of first electrodes or second electrodes is connected to the intermediate busbar. Compared with each interconnecting strip being connected to the intermediate busbar separately, the number of solder joints required to connect to the intermediate busbar can be reduced by half. The narrower busbar can support the reduced number of solder joints, which reduces the number of solder joints, simplifies the welding process, and improves the manufacturing efficiency. Furthermore, since the interconnecting band connecting a pair of first electrodes or a pair of second electrodes can traverse the intermediate busbar, even if the intermediate busbar becomes narrower, it can still ensure that the interconnecting band contacts and welds with the intermediate busbar. Therefore, the width of the intermediate busbar used in the photovoltaic module fabrication provided in this embodiment of the invention can be smaller. When the spacing between cells is reduced, the shading of the intermediate busbar on the edge of the cell can be reduced or avoided, thereby ensuring the photoelectric conversion efficiency of the manufactured photovoltaic module. Attached Figure Description

[0020] Figure 1 This is a schematic diagram illustrating the relationships between various components in a photovoltaic module based on existing technology;

[0021] Figure 2 This is a schematic diagram of the main process of the photovoltaic module manufacturing method provided in the embodiments;

[0022] Figure 3 This is a schematic diagram of the structure of the first back-contact solar cell string provided according to an embodiment of the present invention;

[0023] Figure 4 This is a schematic diagram of the structure of a second back-contact solar cell string provided according to an embodiment of the present invention;

[0024] Figure 5 This is a schematic diagram of a parallel structure of the right end cell of the left sub-cell string and the left end cell of the right sub-cell string in a first back-contact solar cell string according to an embodiment of the present invention.

[0025] Figure 6 It is provided according to the embodiments of the present invention. Figure 5 A cross-sectional structural diagram of the structure shown.

[0026] Figure 7 This is a schematic diagram of another parallel structure of the right end cell of the left sub-cell string and the left end cell of the right sub-cell string in the first back contact solar cell string according to an embodiment of the present invention.

[0027] Figure 8 It is provided according to the embodiments of the present invention. Figure 6 A cross-sectional structural diagram of the structure shown.

[0028] Figure 9 This is a schematic cross-sectional view of a photovoltaic module parallel to a first direction according to an embodiment of the present invention;

[0029] Figure 10 This is a schematic diagram of the main process of fabricating the first back-contact solar cell string 10 included in the photovoltaic module fabrication method provided according to an embodiment of the present invention;

[0030] Figure 11A This is a schematic diagram of the structural changes in steps S1001 to S1004 of the method for preparing a back-contact solar cell string according to an embodiment of the present invention.

[0031] Figure 11B This is a schematic diagram of the structural changes in steps S1005 to S1008 of the method for preparing a back-contact solar cell string according to an embodiment of the present invention.

[0032] Figure 12 This is a schematic diagram of the main process of fabricating the second back contact solar cell string 10 included in the photovoltaic module fabrication method provided according to an embodiment of the present invention;

[0033] Figure 13 This is a schematic diagram of the structure obtained by implementing step S1006, step S1006' or step S1203 according to an embodiment of the present invention.

[0034] Figure 14 This is a schematic diagram of the relative positions and connections between the middle busbar, the back contact solar cell string and the edge busbar in a photovoltaic module arranged according to an embodiment of the present invention.

[0035] The attached figures are labeled as follows:

[0036] 10-Battery string; 100-First back contact solar cell string; 200-Second back contact solar cell string; 11-Sub-cell string; 111-Cell; 111'-First end cell; 111”-Second end cell; 111a-First cell; 111b-Second cell; 1111-First electrode; 1112-Second electrode; 12-Insulator; 13-Intermediate busbar; 14-Interconnector; 20-Cover plate; 30-Encapsulation layer; 31-Front encapsulation film; 32-Rear encapsulation film; 40-Backplate; 50-Edge busbar; 60-Electrical connector. Detailed Implementation

[0037] Figure 1 This diagram illustrates the relationship between the cell string 10, the intermediate busbar 13, the edge busbar 50, and the interconnecting bands in a photovoltaic module provided by the prior art. Figure 1 The existing photovoltaic module shown has the following manufacturing steps: (a) welding existing cell strings 10 using a stringer; (b) laying the front glass and front encapsulant film; (c) assembling the existing cell strings 10 according to... Figure 1The process involves laying the battery strings 10 on the front adhesive film, forming a series-parallel battery array structure through the central busbar 13 and the end busbars 50; step (d): laying the back adhesive film and backsheet (or back glass) on the battery array; step (e): laminating the above materials, and then framing and mounting the junction box to form the prior art back contact solar cell module. In the prior art electrical connection method, in step (c), during the welding process between the central busbar and the battery strings, the two battery strings 10 are connected in parallel. The electrodes on the two battery strings 10 that are welded to the central busbar 13 have the same polarity, and the electrodes with the same polarity are staggered and then welded to the central busbar 13 respectively through interconnecting strips. This results in a large number of welding points with the central busbar 13, making the process cumbersome. Furthermore, a layout machine and a stacking machine are used respectively when laying the battery strings 10 on the front adhesive film and when connecting the central busbar to the interconnecting strips of the battery strings 10. Because the layout machine and the stacking machine... The limited precision (currently, it is difficult for the typesetting machines used in photovoltaic module production to control the precision within 1mm) results in a large distance (about 11mm) between two parallel battery strings 10, which is generally greater than the spacing between the cells in the battery string 10. The intermediate busbar 13 occupies part of the solar cell module area, which limits the module efficiency. Moreover, when forming a multi-row battery array, the battery strings 10 need to be placed multiple times, causing the distance between two parallel battery strings 10 in the battery array to fluctuate between multiple rows, resulting in inconsistent gap distances between parallel battery strings.

[0038] To address existing problems with photovoltaic modules, this invention provides a method for manufacturing a photovoltaic module and a photovoltaic module itself.

[0039] The multiple battery cells connected in series in the embodiments of this invention generally refer to the multiple battery cells arranged in a row or column, wherein the electrodes of every two adjacent battery cells are electrically connected by interconnection. For example... Figure 3 and Figure 4 The sub-battery string 11 is shown.

[0040] In the embodiments of this invention, the correspondence between one structure and another generally occurs as follows: When one structure is arranged horizontally with another, the other structure is located on the extension line of the first structure; when one structure is arranged vertically with another, part or all of the other structure is located directly above or below the first structure. For example, if the first electrode of one battery cell corresponds to the second electrode of another battery cell, then the second electrode of the other battery cell is located on the extension line of the first electrode of the first battery cell. Similarly, if the first electrode of one battery cell corresponds to the second electrode of another battery cell, then the second electrode of the other battery cell is located on the extension line of the first electrode of the first battery cell. For example, if an intermediate busbar corresponds to an insulating component, then the entire area of ​​the intermediate busbar is located directly above the insulating component, and a portion of the insulating component is located directly below the intermediate busbar.

[0041] In the embodiments of the present invention, a structure is disposed above or below another structure in such a way that all or part of the area of ​​the one structure is located directly above or directly below a part of the area of ​​the other structure. For example, if the intermediate busbar is disposed above the insulating member, then the entire area of ​​the intermediate busbar is located directly above a part of the insulating member; or, for example, if the intermediate busbar is disposed below the interconnecting strip, then a part of the intermediate busbar is located directly below a part of the interconnecting strip.

[0042] In the embodiments of the present invention, the electrical connection between the two structures is generally such that the two structures are in direct or indirect contact and are electrically conductive.

[0043] The embodiment of this invention involves placing one structure on top of another structure during the lamination stage of photovoltaic module manufacturing, where the other structure is placed on top of a main surface of one structure, and the other structure is in direct or indirect contact with the first structure. For example, Figure 9 The arrangement of multiple first back-contact solar cell strings 100 and second back-contact solar cell strings 200 alternately laid on the front encapsulation film 31 means that the first back-contact solar cell strings 100 and second back-contact solar cell strings 200 are placed above the front encapsulation film 31, and the first back-contact solar cell strings 100 and second back-contact solar cell strings 200 are in direct contact with the front encapsulation film 31. For example, Figure 9 The post-encapsulation film 32 shown refers to the fact that the post-encapsulation film 32 is placed on top of the battery array formed by multiple first back-contact solar cell strings 100 and multiple second back-contact solar cell strings 200 connected in series, and the post-encapsulation film 32 is in direct contact with the battery array.

[0044] In the embodiments of this invention, the front side of a structure generally refers to the main surface of the structure facing sunlight during the use of the photovoltaic module. Correspondingly, the back side of a structure generally refers to the main surface of the structure facing away from sunlight during the use of the photovoltaic module. For example, the back and front sides of a solar cell refer to the two relatively large, oppositely arranged main surfaces of the cell that serve as the backlight surface (the side facing away from sunlight) and the light-receiving surface (the side facing sunlight) of the photovoltaic module.

[0045] The terms "first" and "second" used in the embodiments of this invention are only for distinguishing the differences in location, structure, or polarity. However, structures made of the same material, such as a first back-contact solar cell string and a second back-contact solar cell string, a first electrode and a second electrode, a first battery cell and a second battery cell, a first end battery cell and a second end battery cell, etc., are not a limitation on the number or order of structures.

[0046] Figure 2 This diagram illustrates the main flowchart of a photovoltaic module fabrication method provided by an embodiment of the present invention. Figure 2 As shown, the photovoltaic module manufacturing method may include the following steps:

[0047] Step S200: Multiple first back contact solar cell strings 100 and multiple second back contact solar cell strings 200 are prepared by a stringer, wherein each first back contact solar cell string 100 and each second back contact solar cell string 200 includes two sub-cell strings placed side by side along a first direction and connected to each other in parallel by an interconnecting strip, the first direction being the length direction of the sub-cell strings;

[0048] In the first back-contact solar cell string 100, the first electrode 1111 of the right end cell 111' of the left sub-cell string 11 corresponds one-to-one with the first electrode 1111 of the left end cell 111" of the right sub-cell string 11 and are electrically connected by an interconnecting strip 14.

[0049] In the second back-contact solar cell string 200, the second electrode 1112 of the right end cell 111' of the left sub-cell string 11 corresponds one-to-one with the second electrode 1112 of the left end cell 111" of the right sub-cell string 11 and are electrically connected by an interconnecting strip 14.

[0050] The first electrode 1111 and the second electrode 1112 have opposite polarities;

[0051] Step S201: Lay out the cover plate 20 and lay the pre-sealing film 31 on the cover plate 20;

[0052] Step S202: Along a second direction perpendicular to the first direction, the first back-contact solar cell string 100 and the second back-contact solar cell string 200 are alternately laid on the front encapsulation film 31 in the order of first back-contact solar cell string 100-second back-contact solar cell string 200...first back-contact solar cell string 100-second back-contact solar cell string 200.

[0053] Step S203: Connect multiple first back-contact solar cell strings 100 and multiple second back-contact solar cell strings 200 in series to form a battery array;

[0054] Step S204: Lay a post-encapsulation film 32 on the battery array, lay a backing plate 40 on the post-encapsulation film 32, and form a laminate after lamination.

[0055] Among them, after lamination, the rear encapsulation film 32 and the front encapsulation film 31 are combined to form the encapsulation layer 30.

[0056] In the aforementioned photovoltaic module manufacturing process, before lamination and layout, the same equipment and processes as string welding are used, or two parallel back-contact solar cell strings are formed simultaneously during the formation of sub-cell strings. Compared to existing technologies that use layout machines and stacking machines to arrange and connect the cell strings formed in the string welding stage during the lamination stage, this method ensures the spacing between the parallel sub-cell strings. Furthermore, it ensures that the spacing between two parallel cells remains consistent with the cell spacing within the sub-cell string, improving the area utilization rate of the photovoltaic module and enhancing its aesthetics. Moreover, achieving parallel connection during the string welding stage... This method reduces the number of steps involved in the layout of cells in parallel and in the intermediate busbar, effectively improving the manufacturing efficiency of photovoltaic modules. When connecting to the intermediate busbar, the corresponding electrodes of the end cells of the two sub-cell strings are connected by an interconnecting strip. This allows the interconnecting strip to be directly connected to the intermediate busbar when electrically connected, achieving the effect that the end cells of both sub-cell strings are connected to the intermediate busbar. Compared with the existing technology where each electrode of the two end cells is connected to the intermediate busbar separately, this method reduces welding by half, simplifies the process, improves manufacturing efficiency, and effectively reduces problems such as poor welding.

[0057] in, Figure 3 and Figure 4 The following are schematic diagrams of the structure of the first back-contact solar cell string and the second back-contact solar cell string used in the fabrication of photovoltaic modules according to embodiments of the present invention. Figures 5 to 8A schematic diagram of the connection relationship of the end cells of the two sub-cell strings in the first back-contact solar cell string is shown. The connection relationship of the end cells of the two sub-cell strings in the second back-contact solar cell string is basically the same as that of the two sub-cell strings in the first back-contact solar cell string, except that the first electrode is replaced by the second electrode. This diagram is omitted in this application.

[0058] like Figure 3 and Figure 4 As shown, the first back-contact solar cell string 100 and the second back-contact solar cell string 200 used in the photovoltaic module fabrication scheme provided in this embodiment of the invention both include two parallel sub-cell strings 11. Each sub-cell string 11 includes multiple cells 111 connected in series. The back side of each cell 111 includes alternating first electrodes 1111 and second electrodes 1112 with opposite polarities. Specifically, the back side of the first cell 111a is arranged alternately in the order of first electrode 1111-second electrode 1112-...-first electrode 1111-second electrode 1112, and the back side of the second cell 111b is arranged alternately in the order of second electrode 1112-first electrode 1111-...-second electrode 1112-first electrode 1111. Figure 3 In the first back-contact solar cell string, each sub-cell string is arranged in the order of first cell 111a-second cell 111b-...-first cell 111a-second cell 111b-first cell 111a. The first electrode of the preceding first cell 1111 is connected in series with the second electrode of the following second cell 111b via an interconnecting strip 14. The first electrode 1111 of the preceding second cell 111b is connected with the second electrode 1112 of the following first cell 111a via an interconnecting strip 14. In two sub-cell strings arranged side-by-side, the first electrode of the right-end cell of the left sub-cell string is connected to the first electrode of the left-end cell of the right sub-cell string via an interconnecting strip, forming a parallel connection. Figure 4 In the second back-contact solar cell string, each sub-cell string is arranged in the order of first cell 111a-second cell 111b-...-first cell 111a-second cell 111b-first cell 111a. The second electrode of the preceding first cell 1111 is connected in series with the first electrode of the following second cell 111b through an interconnecting strip 14. The second electrode 1111 of the preceding second cell 111b is connected with the first electrode 1112 of the following first cell 111a through an interconnecting strip 14. The second electrodes of the cells at the right end of the left sub-cell string and the second electrodes of the cells at the left end of the right sub-cell string are connected by an interconnecting strip to form a parallel connection.

[0059] In both the first and second back-contact solar cell strings, each sub-string 11 includes individual solar cells 111 that can be a single back-contact solar cell, or they can be obtained by dividing a single back-contact solar cell into half, one-third, or one-fifth pieces. For example, a first electrode-second electrode-...-first electrode-second electrode can be alternately arranged on the back side of a front-side back-contact solar cell, with both the first and second electrodes extending along the width of the front-side solar cell. Then, the front-side solar cell is cut into two halves along a length direction perpendicular to the width, one of which can be... Figure 3 and Figure 4 The first half of the battery cell is formed by rotating the other half 180 degrees up and down. Figure 3 and Figure 4 The second solar cell in the process. Of course, the method for preparing the solar cell described in this application is not limited to this.

[0060] The first electrode 1111 and the second electrode 1112 are electrodes with opposite polarities. That is, if the first electrode 1111 is a positive electrode, then the second electrode 1112 is a negative electrode; if the first electrode 1111 is a negative electrode, then the second electrode 1112 is a positive electrode.

[0061] In this first back-contact solar cell string 100, the right end cell 111' of one sub-cell string 11 (i.e., the left sub-cell string 11) and the left end cell 111" of another sub-cell string 11 (i.e., the right sub-cell string 11) are electrically connected by an interconnecting strip, such as... Figures 5 to 8 As shown, Figures 5 to 8 A schematic diagram is shown showing that in the first back-contact solar cell string 100, each pair of corresponding first electrodes of the left-end cell 111' and the left-end cell 111" are connected in parallel via an interconnecting strip. The second electrodes of each pair of corresponding second electrodes of the right-end cell and the left-end cell in the second back-contact solar cell string are connected in parallel via an interconnecting strip in a similar manner, and are not shown in the figure. Specifically, the first electrode 1111 of the right-end cell 111' in one sub-cell string 11 (i.e., the left-side sub-cell string 11) corresponds to the first electrode 1111 of the left-end cell 111" in another sub-cell string 11 (i.e., the right-side sub-cell string 11); in the right-end cell 111' and the left-end cell 111" respectively, each pair of corresponding first electrodes 1111 is electrically connected via an interconnecting strip 14.

[0062] In this context, the right-end battery cell 111' generally refers to the battery cell located on the far right of the sub-battery string 11 when the individual battery cells 111 in the sub-battery string 11 are arranged left and right. The right-end battery cell 111' is a battery cell in the sub-battery string 11. The left-end battery cell 111" generally refers to the battery cell located on the far left of the sub-battery string 11 when the individual battery cells 111 in the sub-battery string 11 are arranged left and right. The second-end battery cell 111" is a battery cell in the sub-battery string.

[0063] Understandably, such as Figure 3 and Figure 4 As shown, in the first back-contact solar cell string 100 or the second back-contact solar cell string 200, the right end cell 111' of one sub-cell string 11 (e.g., the left sub-cell string 11) is adjacent to the left end cell 111" of another sub-cell string 11 (e.g., the right sub-cell string 11).

[0064] Furthermore, in order to further optimize the photovoltaic module manufacturing process, Figures 3 to 8 This illustration shows the connection between two sub-cell strings 11 in a first back-contact solar cell string 100 or a second back-contact solar cell string 200, as provided in an embodiment of the present invention. Figures 5 to 8 The diagrams show the connection relationship between the interconnecting strip 14 and the intermediate busbar 13 connecting the right-end cell 111' of one sub-cell string 11 and the left-end cell 111" of another sub-cell string 11. The first back-contact solar cell string 100 or the second back-contact solar cell string 200 further includes an insulating member 12 and an intermediate busbar 13. The insulating member 12 is disposed between the right-end cell 111' and the left-end cell 111" and is located below the interconnecting strip 14 that electrically connects the right-end cell 111' and the left-end cell 111"; the insulating member 12 contacts the back edge of the right-end cell 111' and the back edge of the left-end cell 111"; the intermediate busbar 13 is disposed above the insulating member 12 and is electrically connected to the interconnecting strip 14 that electrically connects the right-end cell 111' and the left-end cell 111".

[0065] Specifically, there are two possible structures for the intermediate busbar 13 being positioned above the insulating member 12.

[0066] In the first structure, the intermediate busbar 13 is disposed above the insulating member 12: such as Figure 5 and Figure 6 As shown, the intermediate busbar 13 is disposed above the interconnecting band 14, that is, a section of the interconnecting band 14 that overlaps with the intermediate busbar 13 is located between the intermediate busbar 13 and the insulating member 12.

[0067] Additionally, a second structure is formed where the intermediate busbar 13 is positioned above the insulator 12: (e.g.) Figure 7 and Figure 8 As shown, the intermediate busbar 13 can also be located below the interconnecting band 14.

[0068] Taking the first back-contact solar cell string as an example, Figures 5 to 8 As shown, in the first back-contact solar cell string 100, the connection between the right end cell 111' of one sub-cell string 11 (e.g., the left-hand cell 111") and the left end cell 111" of another sub-cell string 11 (e.g., the right-hand cell 111") is achieved by connecting each pair of first electrodes 1111 or each pair of second electrodes 1112 with an interconnecting strip 14. The interconnecting strip 14 and the intermediate busbar 13 can be securely connected via a solder joint, enabling parallel current collection between the first back-contact solar cell string 100 and the second back-contact solar cell string 200. Figure 1 Compared with the existing technology for preparing photovoltaic modules, the first back-contact solar cell string 100 and the second back-contact solar cell string 200 used in this application to prepare photovoltaic modules have half the number of welding points in the middle busbar 13. This can ensure a relatively stable electrical connection even when the middle busbar 13 is narrowed, avoid the problem of multiple welding points, and reduce the possibility of poor soldering.

[0069] The interconnecting strip 14 can be a solder strip, conductive copper wire, etc.

[0070] Among them, the intermediate busbar 13 is generally a tinned copper strip or a conductive tape, etc.

[0071] Furthermore, the gap between the right-end solar cell 111' and the left-end solar cell 111" is equal to the gap between every two adjacent solar cells 111 in the sub-cell string 11. Achieving consistency in the gap or spacing between adjacent solar cells in the back-contact solar cell string improves the aesthetics of the photovoltaic module when the first back-contact solar cell string 100 and the second back-contact solar cell string 200 are used in photovoltaic modules.

[0072] In addition, the insulating component 12 can be a single-layer or multi-layer film made of one or more of the following materials: PET, EVA, EVE, and POE. This single-layer or multi-layer film overlaps the back edges of two adjacent solar cells. The material used for the insulating component 12 is generally the same as the material of the encapsulation layer, so that after the first back-contact solar cell string 100 and the second back-contact solar cell string 200 are applied to the photovoltaic module, the insulating component 12 and the encapsulation layer become an integral structure, preventing the insulating component from affecting the light absorption and photoelectric conversion efficiency of the photovoltaic module, and further improving the consistency and aesthetics of the photovoltaic module's appearance.

[0073] Furthermore, for the insulating component 12, which is a single-layer or multi-layer adhesive film, the width of the intermediate busbar 13 is smaller than the width of the single-layer or multi-layer adhesive film. This reduces or even eliminates the shading of the solar cells by the intermediate busbar 13, thereby ensuring the photoelectric conversion efficiency of the first back-contact solar cell string 100 and the second back-contact solar cell string 200.

[0074] The first back-contact solar cell string 100 and the second back-contact solar cell string 200 used in the above-mentioned photovoltaic module fabrication can be manufactured in the stringing stage. That is, the first back-contact solar cell string 100 and the second back-contact solar cell string 200 provided in the embodiments of the present invention can complete the series-parallel connection process of multiple cells in the first back-contact solar cell string 100 and the second back-contact solar cell string 200 through the stringing stage, complete the parallel conversion connection, and obtain a first back-contact solar cell string 100 containing parallel sub-cell strings or a second back-contact solar cell string 200 containing parallel sub-cell strings through the stringing stage, and apply the first back-contact solar cell string 100 containing parallel sub-cell strings or the second back-contact solar cell string 200 containing parallel sub-cell strings to the stacking stage to fabricate photovoltaic modules.

[0075] Since the first back-contact solar cell string 100 and the second back-contact solar cell string 200 used in the preparation of photovoltaic modules contain two sub-cell strings connected in parallel, the process of arranging and deploying the intermediate busbar and the cell strings on both sides of the intermediate busbar, as well as the welding of the cell strings to the intermediate busbar, can be omitted during the stacking stage of photovoltaic modules. This reduces the difficulty of photovoltaic module preparation. Moreover, the resulting first back-contact solar cell string 100 and second back-contact solar cell string 200 have simple structures, are easy to operate, and are suitable for large-scale promotion and use.

[0076] Furthermore, in the embodiments of the present invention, the first back-contact solar cell string 100 or the second back-contact solar cell string 200 used to prepare the photovoltaic module are as a whole, and the individual cell structures in the two sub-cell strings are identical, so that these cells can be completed through the same placement process, thereby ensuring that the spacing between the parallel cell strings remains consistent.

[0077] Furthermore, in the first back-contact solar cell string 100 and the second back-contact solar cell string 200 used in the fabrication of photovoltaic modules, an insulating element is provided between the right-end cell in one sub-string and the left-end cell in the adjacent sub-string. The insulating element contacts the back edge of the right-end cell and the back edge of the left-end cell. On the one hand, it can isolate the interconnecting band from contacting the cell edge and prevent the intermediate busbar from directly contacting the right-end and left-end cells, so that even if the right-end and left-end cells have a relatively small gap, normal electrical connection between the cells can be guaranteed. On the other hand, it can also provide support for the intermediate busbar, ensuring that the interconnecting band between the intermediate busbar and the right-end and left-end cells has a better electrical connection effect.

[0078] In addition, with Figure 1 In the example shown, the two electrodes (first electrode or second electrode) of the two cells are connected to different interconnecting bands. Compared to the previous method where each electrode is connected to an interconnecting band and then to a busbar, in the first and second back-contact solar cell strings used to prepare photovoltaic modules in this embodiment of the invention, each pair of corresponding first electrodes or each pair of corresponding second electrodes in the right-end cells of one sub-cell string and the left-end cells of another sub-cell string are electrically connected by an interconnecting band. Then, the interconnecting bands connecting each pair of first electrodes or second electrodes are connected to the intermediate busbar. The number of soldering points required to connect to the intermediate busbar is reduced by half, and the narrower busbar can accommodate the reduced number of soldering points. Furthermore, since the interconnecting band connecting a pair of first electrodes or a pair of second electrodes can traverse the intermediate busbar, even if the intermediate busbar becomes narrower, it can still ensure that the interconnecting band contacts and welds with the intermediate busbar. Therefore, the width of the intermediate busbar in the first and second back-contact solar cell strings used to prepare photovoltaic modules in this embodiment of the invention can be smaller. When the spacing between cells is reduced, the shading of the intermediate busbar on the edge of the cells can be reduced or avoided, thereby ensuring the photoelectric conversion efficiency of the photovoltaic module made using the back-contact solar cell string.

[0079] In the embodiments of the present invention, the first back-contact solar cell string 100 and the second back-contact solar cell string 200 used to prepare photovoltaic modules are both connected in series-parallel. This ensures that the efficiency of the photovoltaic modules is increased. At the same time, the manufacturing difficulty of photovoltaic modules is greatly reduced because the intermediate busbar and the series welding process between the intermediate busbar and the solder strip are omitted in the stacking stage of the photovoltaic modules.

[0080] It is worth noting that the photovoltaic module fabrication method provided in this embodiment of the invention can directly use pre-prepared modules. Figure 3 The first back-contact solar cell string 100 shown and Figure 4 The second back-contact solar cell string 200 shown enables the photovoltaic module fabrication method to be completed in the stacking stage of existing photovoltaic module fabrication processes. The entire process requires no adjustments to existing equipment, resulting in photovoltaic modules with improved performance and appearance while effectively controlling costs. The above process yields... Figure 9 A schematic diagram of the cross-sectional structure of a photovoltaic module parallel to the first direction (the direction of extension of the sub-cell string) is shown.

[0081] In addition, the photovoltaic module manufacturing method provided in this embodiment of the invention may also include Figure 3 The first back-contact solar cell string 100 shown and Figure 4 The fabrication process of the second back-contact solar cell string 200 is shown. Among them, regardless of... Figure 3 The first back-contact solar cell string 100 shown and Figure 4 The second back-contact solar cell string 200 shown can be fabricated using two different processes.

[0082] Specifically, targeting Figure 3 The first fabrication process of the first back-contact solar cell string 100 shown may include the following steps:

[0083] Perform the following during the stringing stage: Figure 10 The following steps S1001 to S1008 are shown:

[0084] Step S1001: Place a first battery cell 111a with its back side facing up at a preset position. The back side of the first battery cell 111a is provided with a first electrode 1111 and a second electrode 1112, which are arranged alternately in the following order: first electrode 1111-second electrode 1112...first electrode 1111-second electrode 1112;

[0085] The following steps S1002 and S1003 are repeated until a sub-battery string 11 is fabricated, at which point the loop ends:

[0086] Step S1002: Place a second battery cell 111b with its back side facing up at the adjacent position of the first battery cell 111a. The back side of the second battery cell 111b with its back side facing up is provided with a first electrode 1111 and a second electrode 1112, and they are arranged alternately in the following order: second electrode 1112-first electrode 1111... second electrode 1112-first electrode 1111. The first electrode 1111 of the first battery cell 111a corresponds one-to-one with the second electrode 1112 of the adjacent second battery cell 111b and is electrically connected to each other through an interconnecting strip 14.

[0087] Step S1003: Place a first battery cell 111a with its back facing up at the adjacent position of the already placed second battery cell 111b. The first electrode 1111 of the second battery cell 111b corresponds one-to-one with the second electrode 1112 of the adjacent first battery cell 111a and is electrically connected by an interconnecting strip 14.

[0088] Step S1004: Place another first battery piece 111a, facing backwards, next to the first battery piece 111' of the right end battery piece 111' of the sub-battery string 11 on the right side, with the battery piece 111' facing backwards.

[0089] Step S1005: Place an insulating member 12 between the right end battery piece 111' and the adjacent left end battery piece 111" and make the insulating member 12 completely overlap the opposite ends in the first direction over the entire edge of the back of the right end battery piece 111' and the left end battery piece 111" extending in the second direction.

[0090] Step S1006: The first electrode 1111 of the right end battery cell 111' and the first electrode 1111 of the adjacent left end battery cell 111” correspond one-to-one and are connected by an interconnecting strip, and all interconnecting strips between the right end battery cell 111' and the adjacent left end battery cell 111” are electrically connected to the intermediate busbar 13 extending along the second direction.

[0091] The following steps S1007 and S1008 are repeated until another sub-battery string 11 is prepared, at which point the loop ends:

[0092] Step S1007: Place a second battery cell 111b with its back facing up next to the first battery cell 111a, which has been placed as the left end battery cell 111 of the right sub-battery string 11. The second electrode 1112 of the first battery cell 111a and the first electrode 1111 of the second battery cell 111b correspond one-to-one and are connected by an interconnecting line.

[0093] Step S1008: Place a first battery cell 111a with its back facing up at the adjacent position of the already placed second battery cell 111b. The second electrode 1112 of the second battery cell 111b corresponds one-to-one with the first electrode 111a of the adjacent first battery cell 111a and is electrically connected by an interconnecting line.

[0094] The connection between the interconnect strip and the first or second electrode can be achieved through existing connection methods such as welding or connection with conductive adhesive.

[0095] During steps S1001 to S1004, the structural changes of the first back-contact solar cell string 100 can be as follows: Figure 11A As shown. During steps S1005 to S1008, the structural changes of the first back-contact solar cell string 100 can be as follows: Figure 11B As shown.

[0096] The above can be obtained through steps S1001 to S1008. Figure 3 The first back-contact solar cell string 100 is shown.

[0097] It is worth noting that steps S1001 to S1008 can be implemented using a stringer for manufacturing battery strings in the prior art. That is, the first back contact solar cell string 100 is prepared in the stringing stage of the existing stringer, without the need to add new production equipment, so as to effectively control the production cost of the first back contact solar cell string 100.

[0098] In addition, regarding Figure 4 The first fabrication process of the second back-contact solar cell string 200 shown is the same as described above. Figure 10 The first fabrication process for the first back-contact solar cell string 100 shown is similar and may specifically include the following steps (not shown in the figure):

[0099] Step S1001': Place a first battery cell 111a with its back side facing up at a preset position. The back side of the first battery cell 111a is provided with a first electrode 1111 and a second electrode 1112, which are arranged alternately in the following order: first electrode 1111-second electrode 1112...first electrode 1111-second electrode 1112.

[0100] Repeat steps S1002' and S1003' until the left sub-battery string 11 is fabricated, then end the loop:

[0101] Step S1002': A second battery cell 111b with its back side facing up is placed at an adjacent position to the first battery cell 111a that has already been placed. The back side of the second battery cell 111b with its back side facing up is provided with a first electrode 1111 and a second electrode 1112, and they are arranged alternately in the following order: second electrode 1112-first electrode 1111... second electrode 1112-first electrode 1111. The second electrode 1112 of the first battery cell 111a corresponds one-to-one with the first electrode 1111 of the adjacent second battery cell 111b and is electrically connected to each other through an interconnecting strip 14.

[0102] Step S1003': Place a first battery cell 111a with its back facing up at the adjacent position of the already placed second battery cell 111b. The second electrode 1112 of the second battery cell 111b corresponds one-to-one with the first electrode 1111 of the adjacent first battery cell 111a and is electrically connected to each other through an interconnecting strip 14.

[0103] Step S1004': Place another first battery piece 111a, facing backwards, next to the first battery piece 111' of the right end battery piece 111' of the sub-battery string 11 on the right side, adjacent to the first battery piece 111a of the right end battery piece 111' of the sub-battery string 11 on the left side;

[0104] Step S1005': Place an insulating member 12 between the right end battery piece 111' and the adjacent left end battery piece 111" and make the insulating member 12 completely overlap the opposite ends in the first direction over the entire edge of the back of the right end battery piece 111' and the left end battery piece 111" extending in the second direction.

[0105] Step S1006': The second electrode 1112 of the right end battery cell 111' and the second electrode 1112 of the adjacent left end battery cell 111" correspond one-to-one and are connected by an interconnecting strip, and all interconnecting strips between the right end battery cell 111' and the adjacent left end battery cell 111" are electrically connected to the intermediate busbar 13 extending along the second direction.

[0106] Repeat steps S1007' and S1008' until the sub-battery string 11 on the right is fabricated, then end the loop:

[0107] Step S1007': Place a second battery cell 111b with its back facing up next to the first battery cell 111a, which is the left end battery cell 111 of the sub-battery string 11 on the right side, at the adjacent position of the first battery cell 111a which has been placed as the left end battery cell 111”. The first electrode 1111 of the first battery cell 111a and the second electrode 1112 of the second battery cell 111b correspond one-to-one and are connected by an interconnecting line.

[0108] Step S1008': Place a first battery cell 111a with its back facing up at the adjacent position of the already placed second battery cell 111b. The first electrode 1111 of the second battery cell 111b corresponds one-to-one with the second electrode 1112 of the adjacent first battery cell 111a and is electrically connected by an interconnecting line.

[0109] Furthermore, for the second fabrication process of the first back contact solar cell string 100 and the second fabrication process of the second back contact solar cell string 200, before fabricating the first back contact solar cell string 100 and the second back contact solar cell string 200, the process may further include the step of fabricating multiple sub-cell strings, wherein in each sub-cell string, the cells are arranged alternately in the order of first cell 111a, second cell 111b, first cell 111a, ..., second cell 111b, first cell 111a.

[0110] Based on the fabricated sub-cell strings, such as Figure 12 As shown, a second fabrication process for the first back-contact solar cell string 100 may include the following steps:

[0111] Step S1201: Select two sub-battery strings 11 and place them side by side along the first direction, wherein the left end of the left sub-battery string (11) is the second electrode and the right end is the first electrode, and the left end of the right sub-battery string (11) is the first electrode and the right end is the second electrode.

[0112] Step S1202: An insulating member 12 is placed between the right end battery piece 111' of the left sub-battery string 11 and the left end battery piece 111” of the right sub-battery string 11, and the insulating member 12 is completely overlapped on the back of the right end battery piece 111' and the left end battery piece 111” in the first direction, respectively, covering the entire edge extending in the second direction. The first electrode 1111 of the right end battery piece 111' and the first electrode 1111 of the left end battery piece 111” correspond one-to-one and are respectively connected by an interconnecting wire.

[0113] Step S1203: Electrically connect all interconnecting strips between the right end battery cell 111' and the left end battery cell 111" to the intermediate busbar 13 extending along the second direction.

[0114] Based on the fabricated sub-cell strings, the second fabrication process of the second back-contact solar cell string 200 is similar to the second fabrication process of the first back-contact solar cell string 100 described above. Specifically, it may include: selecting two sub-cell strings 11 and placing them side by side along a first direction, wherein the left end of the left sub-cell string (11) is a first electrode and the right end is a second electrode, and the left end of the right sub-cell string (11) is a second electrode and the right end is a first electrode, and the battery cell 111' at the right end of the left sub-cell string 11 and the battery cell 111' at the left end of the right sub-cell string 11 are connected. An insulating member 12 is placed between 111”, and the opposite ends of the insulating member 12 in the first direction are respectively completely covered and overlapped over the entire edge of the back of the right end battery cell 111' and the left end battery cell 111” extending in the second direction; the second electrode 1112 of the right end battery cell 111' and the second electrode 1112 of the left end battery cell 111” correspond one-to-one and are electrically connected by an interconnecting strip, and then all interconnecting strips between the right end battery cell 111' and the left end battery cell 111” are electrically connected to the intermediate busbar 13 extending in the second direction.

[0115] The second manufacturing process for the first back-contact solar cell string 100 and the second back-contact solar cell string 200 can also be carried out in the stringing stage of the existing stringer, without the need to add new production equipment, so as to effectively control the production cost of the first back-contact solar cell string 100 and the second back-contact solar cell string 200.

[0116] Furthermore, there are two ways to implement the above steps S1006, S1006', or S1203.

[0117] Method 1: Place a central busbar 13 above the multiple interconnecting strips between the right end battery cell 111' and the left end battery cell 111" at the position corresponding to the insulating member 12, and connect the interconnecting strips to the central busbar 13 by welding.

[0118] Method 2: A central busbar 13 is placed above the insulating component 12. Each pair of corresponding first electrodes 1111 of the right-end battery cell 111' and the left-end battery cell 111" is connected by an interconnecting strip located above the central busbar 13. The interconnecting strip is then welded to the central busbar 13. This method 2 yields the following result: Figure 13 The diagram shown is a structural schematic.

[0119] That is, before or after laying the interconnecting strip between the right end battery cell 111' and the left end battery cell 111", a middle busbar 13 is laid on the insulating member 12.

[0120] Both of the above methods can achieve steps S1006, S1006', or S1203, allowing users to flexibly choose the required implementation method according to their needs, thereby improving the flexibility of preparing the first back contact solar cell string 100 and the second back contact solar cell string 200 with differentiated structures.

[0121] Furthermore, during the formation of the battery array in step S203 above, the ends of multiple back-contact solar cell strings 10 can be connected in pairs via edge busbars 50.

[0122] Specifically, the process of forming the battery array in step S203 above may include the following steps (not shown in the figure):

[0123] Step 3-1: Weld interconnecting strips 14 to each second electrode 1112 of the left end cell of the left sub-cell string 11 in each first back contact solar cell string 100 and to each second electrode 1112 of the right end cell of the right sub-cell string 12; weld interconnecting strips 14 to each first electrode 1111 of the left end cell of the left sub-cell string 11 in each second back contact solar cell string 100 and to each first electrode 1111 of the right end cell of the right sub-cell string 12.

[0124] Step 3-2: Connect the interconnecting strip 14 welded to the second electrode 1112 of each second electrode 1112 of the left end cell of the left sub-cell string 11 in each first back-contact solar cell string 100 and the interconnecting strip 14 welded to the first electrode 1111 of the left end cell of the left sub-cell string 11 in the next adjacent second back-contact solar cell string 200 through an edge busbar 50 extending in the second direction; connect the interconnecting strip 14 welded to the second electrode 1112 of each second electrode 1112 of the right end cell of the right sub-cell string 11 in the first back-contact solar cell string 100 and the interconnecting strip 14 welded to the first electrode 1111 of the right end cell of the right sub-cell string 11 in the next adjacent second back-contact solar cell string 200 through an edge busbar 50 extending in the second direction.

[0125] Step 3-3: Connect the intermediate bus 13 in each second back-contact solar cell string 200 and the intermediate bus 13 in the next adjacent first back-contact solar cell string 100 via the electrical connector 60.

[0126] Regarding the battery array formation process in step S203 above, Figure 14 This diagram illustrates the relative positions and connections between the middle busbar 13, the first back-contact solar cell string 100, the second back-contact solar cell string 200, and the edge busbar 50 in a photovoltaic module.

[0127] Furthermore, embodiments of the present invention provide a photovoltaic module. Figure 9 A schematic diagram of the cross-sectional structure of a photovoltaic module parallel to the first direction is shown. Figure 14 This diagram illustrates the relative positions and connections between the central busbar 13, the back-contact solar cell string 12, and the edge busbar 50 in a photovoltaic module. Figure 9 As shown, the photovoltaic module may include: a cover plate 20, an encapsulation layer 30, a back sheet 40, and multiple back-contact solar cell strings 10 arranged side-by-side and connected in series, each containing two parallel sub-cell strings 11.

[0128] like Figures 3 to 8 As shown, in each first back-contact solar cell string 100 and each second back-contact solar cell string 200, the right end cell 111' of one sub-cell string 11 and each pair of corresponding first electrodes 1111 or second electrodes 1112 with the same polarity in the left end cell 111" of another sub-cell string 11 are electrically connected by an interconnecting strip, and the first electrodes 1111 and the second electrodes 1112 have opposite polarities.

[0129] The gap between the right end battery cell 111' and the left end battery cell 111" is equal to the gap between every two adjacent battery cells 111 in the sub-battery string 11.

[0130] In addition, such as Figure 9 As shown, the encapsulation layer 30 is used to encapsulate multiple back-contact solar cell strings 10 arranged side by side and connected in series between the cover plate 20 and the back plate 40.

[0131] The encapsulation layer 30 is formed by the front encapsulation film 31 and the rear encapsulation film 32 during the lamination process.

[0132] Furthermore, in each of the first back-contact solar cell strings 100 and the second back-contact solar cell strings 200 of the aforementioned photovoltaic module, the gap between the right-end cell 111' and the left-end cell 111" is equal to the gap between every two adjacent cells 111 in the sub-cell string 11. This improves the compactness of the photovoltaic module arrangement, thereby effectively increasing the effective area ratio of the photovoltaic module.

[0133] In the photovoltaic module described above, each of the first back-contact solar cell strings 100 and the second back-contact solar cell strings 200 includes an intermediate busbar 13 disposed above or below the interconnecting band between the first end cell 111' and the second end cell 111".

[0134] In the aforementioned photovoltaic module, the insulating element 12 in each of the first back-contact solar cell string 100 and the second back-contact solar cell string 200 is a single-layer or multi-layer encapsulated film made of one or more materials such as PET, EVA, EVE and POE. It is generally made of the same material as the front encapsulation film 31 and the rear encapsulation film 32. During the lamination process, the insulating element 12 can form an integral structure with the encapsulation layer 30, thereby avoiding the influence of the insulating element 12 on the photoelectric conversion efficiency of the photovoltaic module.

[0135] The back panel can be made of glass or other materials.

[0136] To achieve series connection between multiple first back-contact solar cell strings 100 and second back-contact solar cell strings 200 arranged side-by-side in the aforementioned photovoltaic module, in each adjacent pair of first back-contact solar cell strings 100 and second back-contact solar cell strings 200, the first back-contact solar cell string includes a structure with a middle busbar 13 electrically connected to a first electrode 1111; the second back-contact solar cell string includes a structure with a middle busbar 13 electrically connected to a second electrode 1112. For example, the first back-contact solar cell string is... Figure 3 The back-contact solar cell string with the structure shown is such that the second back-contact solar cell string adjacent to the first back-contact solar cell string is... Figure 4 The diagram shows a back-contact solar cell string structure. The relative positions of the first and second back-contact solar cell strings can be interchanged, but it is necessary to ensure that the relative relationship between any two adjacent first back-contact solar cell strings 100 and second back-contact solar cell strings 200 in the photovoltaic module satisfies the structural relationship described above. For example, regarding... Figure 14 The arrangement shown, comprising multiple first back-contact solar cell strings 100 and second back-contact solar cell strings 200, can be Figure 3 The first back contact solar cell string 100 of the structure shown is with Figure 4 The second back contact solar cell strings in the structure shown are arranged alternately.

[0137] Furthermore, such as Figure 9 and Figure 14 As shown, the photovoltaic module may further include: an edge busbar 50, wherein, as Figure 14 As shown, the ends of multiple first back-contact solar cell strings 100 and second back-contact solar cell strings 200 are connected in pairs via an edge busbar 50. Wherein, as... Figure 14 As shown, the connection of two strings in series via edge busbars 50 generally refers to six strings of alternating first back-contact solar cell strings 100 and second back-contact solar cell strings 200 arranged from bottom to top (first back-contact solar cell string 100 - second back-contact solar cell string 200 - first back-contact solar cell string 100 - second back-contact solar cell string 200 - first back-contact solar cell string 100 - second back-contact solar cell string 200). That is, the two ends of the first back-contact solar cell string 100 of the first string and the adjacent second back-contact solar cell string 200 of the six strings arranged from bottom to top are connected in series via two edge busbars 50 respectively (for example, the first string is...). Figure 3 The first back-contact solar cell string 100 structure shown is shown, and the second string is... Figure 4 The structure of the second back-contact solar cell string 200 shown is as follows. Figure 3The left end of the structure shown is used to connect the interconnecting strip of the second electrode of the battery cell and Figure 4 The left end of the structure shown is used to connect the interconnecting strip of the first electrode of the battery cell to the same edge busbar 50, thereby achieving... Figure 3 The structure shown and Figure 4 The structure shown is connected in series on the left side. Figure 3 The structure shown and Figure 4 Perform the same operation on the right side of the structure shown to achieve... Figure 3 The structure shown and Figure 4 The structure shown is connected in series on the right side (details omitted here); the two ends of the first back-contact solar cell string 100 of the third string and the second back-contact solar cell string 200 of the fourth string, arranged from bottom to top, are connected in series through two edge busbars 50 respectively; the two ends of the first back-contact solar cell string 100 of the fifth string and the second back-contact solar cell string 200 of the sixth string, arranged from bottom to top, are connected in series through two edge busbars 50 respectively; the connection process of the third and fourth strings, and the fifth and sixth strings is similar to that of the first and second strings mentioned above, and will not be described again here.

[0138] Furthermore, such as Figure 14 As shown, the photovoltaic module may further include: an electrical connector 60, wherein, for other first back-contact solar cell strings (e.g., excluding the first back-contact solar cell string 100 of the first string and the second back-contact solar cell string 200 of the sixth string located at the edge) Figure 14 The third and fifth strings of the six strings arranged from bottom to top) and other second back-contact solar cell strings (e.g., Figure 14 The second and fourth strings of the six strings arranged from bottom to top in the diagram, and the intermediate busbars 13 of the other first back-contact solar cell strings and the other second back-contact solar cell strings are electrically connected in pairs via electrical connectors 60. Specifically, the electrical connection of the intermediate busbars 13 of the other first back-contact solar cell strings and the other second back-contact solar cell strings via electrical connectors 60 means, for example... Figure 14 As shown, the intermediate busbars 13 of the second and third strings are electrically connected via electrical connectors 60; the intermediate busbars 13 of the fourth and fifth strings are also electrically connected via electrical connectors 60. This process ensures that the circuit structure of the photovoltaic module is consistent with that of existing photovoltaic modules, allowing the photovoltaic module provided in this embodiment to still be implemented using existing technology in subsequent testing and junction box installation processes. The electrical connectors 60 can be made of the same material as the intermediate busbars 13 to further improve the aesthetics and visual appeal of the photovoltaic module.

[0139] It is worth noting that the aforementioned first back-contact solar cell string 100 and second back-contact solar cell string 200 can also be replaced by shingled cell strings, shingled cell strings, conventional cell strings, etc., composed of cells with electrodes on both the front and back sides.

[0140] Furthermore, embodiments of the present invention also provide a power station, which may include the photovoltaic modules provided in the above embodiments.

[0141] The following two specific embodiments illustrate in detail the preparation method of the photovoltaic module described above.

[0142] Example 1:

[0143] Step A1: Lay a glass cover plate on the stacking platform, and lay an EVA pre-sealing film on the glass cover plate;

[0144] Step B1, apply the encapsulating film to the EVA pre-encapsulation film according to... Figure 14 The structure shown has multiple first back-contact solar cell strings and second back-contact solar cell strings arranged alternately, and an edge busbar is laid at the edge of the alternating arrangement of multiple first back-contact solar cell strings and second back-contact solar cell strings.

[0145] Step C1: Connect the cells at the edges of the alternating arrangement of multiple first back-contact solar cell strings and second back-contact solar cell strings in series to the corresponding edge busbars.

[0146] Step D1: For the other first back contact solar cell strings and other second back contact solar cell strings except for the first back contact solar cell strings and second back contact solar cell strings located at the edge, connect the intermediate busbars contained in the other first back contact solar cell strings and other second back contact solar cell strings in pairs with conductive adhesive.

[0147] Step E1: Perform performance testing on the structure of D1;

[0148] Step F1: Lay a post-encapsulation film on the structure that passed test D1, and lay a backing plate on the post-encapsulation film;

[0149] Step G1: Lamination is performed on the structure formed by F1 to fuse the post-encapsulation film and the pre-encapsulation film into a single structure, thereby achieving encapsulation.

[0150] Example 2:

[0151] Step A2, during the string soldering stage, such as Figure 11A As shown, a first battery cell with its back facing up is placed at a preset position, and an interconnecting strip is connected to each of the first electrodes included on the back of the first battery cell.

[0152] Repeat step B2 until a sub-cell string 11 is fabricated, then end the loop.

[0153] Step B2: Place a new first battery cell with its back facing up at an adjacent position to the already placed first battery cell, wherein the first electrode of the newly placed first battery cell with its back facing up corresponds to the second electrode of the adjacent first battery cell; and connect the first electrode of the newly placed first battery cell with the corresponding second electrode of the adjacent first battery cell using a stringer.

[0154] Step C2: Place a second battery cell with its back facing upwards in the extending direction of a sub-battery string, with the first electrode of the second battery cell corresponding to the first electrode of the adjacent first battery cell;

[0155] Step D2: Place an EVA film between the second battery cell and the adjacent first battery cell, and make the back edge of the second battery cell and the back edge of the adjacent first battery cell support the EVA film.

[0156] Step E2: Connect each pair of corresponding first electrodes in the second cell and the adjacent first cell through an interconnecting strip using a stringer, and connect the multiple interconnecting strips between the second cell and the adjacent first cell through a central busbar.

[0157] The loop continues until another sub-cell string 11 is produced, at which point the loop ends.

[0158] Step F2: Place a second battery cell with its back facing up next to the already placed second battery cell, wherein the first electrode of the replaced second battery cell with its back facing up corresponds to the second electrode of the adjacent second battery cell; connect the first electrode of the replaced second battery cell with the corresponding second electrode in the adjacent second battery cell using a stringer.

[0159] Steps G2 to M2 are the same as steps A1 to G1 above, and will not be repeated here.

[0160] The above steps are provided only to help understand the method, structure, and core ideas of this invention. Those skilled in the art can make various improvements and modifications to this invention without departing from its principles, and these improvements and modifications also fall within the scope of protection of the claims.

Claims

1. A method for manufacturing a photovoltaic module, characterized in that, include: Step (2-0): Multiple first back-contact solar cell strings (100) and multiple second back-contact solar cell strings (200) are fabricated using a stringer, wherein each first back-contact solar cell string (100) and each second back-contact solar cell string (200) includes two sub-cell strings arranged side-by-side along a first direction and connected to each other in parallel by an interconnecting strip, wherein the first direction is the length direction of the sub-cell strings. In the first back-contact solar cell string (100), the first electrode (1111) of the right end cell (111') of the left sub-cell string (11) corresponds one-to-one with the first electrode (1111) of the left end cell (111") of the right sub-cell string (11) and is electrically connected by an interconnecting strip (14). In the second back-contact solar cell string (200), the second electrode (1112) of the right end cell (111') of the left sub-cell string (11) corresponds one-to-one with the second electrode (1112) of the left end cell (111") of the right sub-cell string (11) and is electrically connected by an interconnecting strip (14). The first electrode (1111) and the second electrode (1112) have opposite polarities; Step (2-1): Lay the cover plate (20) and lay the pre-sealing film (31) on the cover plate (20); Step (2-2): Along a second direction perpendicular to the first direction, the first back-contact solar cell string (100) and the second back-contact solar cell string (200) are alternately laid on the front encapsulation film (31) in the order of first back-contact solar cell string (100) - second back-contact solar cell string (200) ... first back-contact solar cell string (100) - second back-contact solar cell string (200); Step (2-3): Connect multiple first back-contact solar cell strings (100) and multiple second back-contact solar cell strings (200) in series to form a battery array; Steps (2-4): A post-encapsulation film (32) is laid on the battery array, a backplate (40) is laid on the post-encapsulation film (32), and a laminate is formed after lamination.

2. The photovoltaic module manufacturing method according to claim 1, characterized in that, In step (2-0), fabricating the first back-contact solar cell string (100) includes: Step (1-1a): Place a first battery cell (111a) with its back side facing up at a preset position. The back side of the first battery cell (111a) is provided with a first electrode (1111) and a second electrode (1112) and arranged alternately in the following order: first electrode (1111) - second electrode (1112) ... first electrode (1111) - second electrode (1112). Repeat steps (1-2a) and (1-3a) until the sub-cell string (11) on the left is fabricated, then end the cycle: Step (1-2a): Place a second battery cell (111b) with its back side facing up at the adjacent position of the first battery cell (111a). The back side of the second battery cell (111b) with its back side facing up is provided with a first electrode (1111) and a second electrode (1112), and they are arranged alternately in the following order: second electrode (1112) - first electrode (1111) ... second electrode (1112) - first electrode (1111). The first electrode (1111) of the first battery cell (111a) corresponds one-to-one with the second electrode (1112) of the adjacent second battery cell (111b) and is electrically connected by an interconnecting strip (14). Step (1-3a): Place a first battery cell (111a) with its back facing up next to the second battery cell (111b) that has already been placed. The first electrode (1111) of the second battery cell (111b) corresponds one-to-one with the second electrode (1112) of the adjacent first battery cell (111a) and is electrically connected by an interconnecting strip (14). Step (1-4a): Place a first battery piece (111a) of the left end battery piece (111”) of the sub-battery string (11) on the right side, with its back facing up, next to the first battery piece (111a) of the right end battery piece (111”) of the sub-battery string (11) on the left side. Step (1-5a): Place an insulating member (12) between the right end battery piece (111') and the adjacent left end battery piece (111"), and make the insulating member (12) completely overlap the opposite ends of the right end battery piece (111') and the left end battery piece (111") on the entire edge of the back of the right end battery piece (111') and the left end battery piece (111") extending in the second direction. In step (1-6a), the first electrode (1111) of the right end battery cell (111') and the first electrode (1111) of the adjacent left end battery cell (111") correspond one-to-one and are connected by an interconnecting strip, and all interconnecting strips between the right end battery cell (111') and the adjacent left end battery cell (111") are electrically connected to the intermediate busbar (13) extending along the second direction; Repeat steps (1-7a) and (1-8a) until the sub-cell string (11) on the right is fabricated, then end the cycle: Step (1-7a): Place a second battery cell (111b) with its back facing up next to the first battery cell (111a) which is the left end battery cell (111”) of the sub-battery string (11) on the right side. The second electrode (1112) of the first battery cell (111a) and the first electrode (1111) of the second battery cell (111b) correspond one-to-one and are connected by an interconnecting line. Step (1-8a): Place a first battery cell (111a) with its back facing up at the adjacent position of the already placed second battery cell (111b). The second electrode (1112) of the second battery cell (111b) corresponds one-to-one with the first electrode (1111) of the adjacent first battery cell (111a) and is electrically connected by an interconnecting line.

3. The photovoltaic module manufacturing method according to claim 2, characterized in that, In step (2-0), fabricating the second back-contact solar cell string (200) includes: Step (1-1b): Place a first battery cell (111a) with its back side facing up at a preset position. The back side of the first battery cell (111a) is provided with a first electrode (1111) and a second electrode (1112) and arranged alternately in the following order: first electrode (1111) - second electrode (1112) ... first electrode (1111) - second electrode (1112). Repeat steps (1-2b) and (1-3b) until the sub-cell string (11) on the left is fabricated, then end the cycle: Step (1-2b): Place a second battery cell (111b) with its back side facing up at the adjacent position of the first battery cell (111a). The back side of the second battery cell (111b) with its back side facing up is provided with a first electrode (1111) and a second electrode (1112), and they are arranged alternately in the following order: second electrode (1112) - first electrode (1111) ... second electrode (1112) - first electrode (1111). The second electrode (1112) of the first battery cell (111a) corresponds one-to-one with the first electrode (1111) of the adjacent second battery cell (111b) and is electrically connected to each other through an interconnecting strip (14). Step (1-3b): Place a first battery cell (111a) with its back facing up at the adjacent position of the already placed second battery cell (111b). The second electrode (1112) of the second battery cell (111b) corresponds one-to-one with the first electrode (1111) of the adjacent first battery cell (111a) and is electrically connected by an interconnecting strip (14). Step (1-4b): Place a first battery piece (111a) of the left end battery piece (111”) of the sub-battery string (11) on the right side, with its back facing up, next to the first battery piece (111a) of the right end battery piece (111”) of the sub-battery string (11) on the left side. Step (1-5b): Place an insulating member (12) between the right end battery piece (111') and the adjacent left end battery piece (111"), and make the insulating member (12) completely overlap the opposite ends of the right end battery piece (111') and the left end battery piece (111") on the entire edge of the back of the right end battery piece (111') and the left end battery piece (111") extending in the second direction. In step (1-6b), the second electrode (1112) of the right end battery cell (111') and the second electrode (1112) of the adjacent left end battery cell (111") correspond one-to-one and are connected by an interconnecting strip, and all interconnecting strips between the right end battery cell (111') and the adjacent left end battery cell (111") are electrically connected to the intermediate busbar (13) extending along the second direction; Repeat steps (1-7b) and (1-8b) until the sub-cell string (11) on the right is fabricated, then end the cycle: Step (1-7b): Place a second battery cell (111b) with its back facing up next to the first battery cell (111a) of the left end battery cell (111”) of the sub-battery string (11) on the right side, where the first electrode (1111) of the first battery cell (111a) and the second electrode (1112) of the second battery cell (111b) correspond one-to-one and are connected by an interconnecting line. Step (1-8b): Place a first battery cell (111a) with its back facing up next to the already placed second battery cell (111b). The first electrode (1111) of the second battery cell (111b) corresponds one-to-one with the second electrode (1112) of the adjacent first battery cell (111a) and is connected by an interconnecting line.

4. The photovoltaic module manufacturing method according to claim 1, characterized in that, Before step (2-0), a step of preparing multiple sub-cell strings is also included, wherein in each sub-cell string, the first cell (111a), the second cell (111b), the first cell (111a), ... the second cell (111b), the first cell (111a) are arranged alternately and connected in series with each other in the order of first cell (111a), the back of the first cell (111a) is provided with a first electrode (1111) and a second electrode (1112) and are arranged alternately in the following order: first electrode (1111)-second electrode (1112) ... first electrode (1111)-second electrode (1112); the back of the second cell (111b) is provided with a first electrode (1111) and a second electrode (1112) and are arranged alternately in the following order: second electrode (1112)-first electrode (1111) ... second electrode (1112)-first electrode (1111).

5. The photovoltaic module manufacturing method according to claim 4, characterized in that, In step (2-0), fabricating the first back-contact solar cell string (100) includes: Two sub-battery strings (11) are selected and placed side by side along a first direction. The left end of the left sub-battery string (11) is the second electrode and the right end is the first electrode, and the left end of the right sub-battery string (11) is the first electrode and the right end is the second electrode. An insulating member (12) is placed between the right end battery piece (111') of the left sub-battery string (11) and the left end battery piece (111") of the right sub-battery string (11). The insulating member (12) is positioned so that its opposite ends in the first direction are respectively The battery completely overlaps the entire edge extending in the second direction on the back of the right end battery cell (111') and the left end battery cell (111"); the first electrode (1111) of the right end battery cell (111') and the first electrode (1111) of the left end battery cell (111") correspond one-to-one and are electrically connected by an interconnecting strip, and then all interconnecting strips between the right end battery cell (111') and the left end battery cell (111") are electrically connected to the intermediate busbar (13) extending in the second direction.

6. The photovoltaic module manufacturing method according to claim 5, characterized in that, In step (2-0), fabricating the second back-contact solar cell string (200) includes: Two sub-battery strings (11) are selected and placed side by side along a first direction. The left end of the left sub-battery string (11) is the first electrode and the right end is the second electrode, and the left end of the right sub-battery string (11) is the second electrode and the right end is the first electrode. An insulating member (12) is placed between the right end battery piece (111') of the left sub-battery string (11) and the left end battery piece (111") of the right sub-battery string (11). The insulating member (12) is positioned so that its opposite ends in the first direction are respectively The battery completely overlaps the entire edge extending in the second direction on the back of the right end battery cell (111') and the left end battery cell (111"); the second electrode (1112) of the right end battery cell (111') and the second electrode (1112) of the left end battery cell (111") correspond one-to-one and are electrically connected by an interconnecting strip, and then all interconnecting strips between the right end battery cell (111') and the left end battery cell (111") are electrically connected to the intermediate busbar (13) extending in the second direction.

7. The photovoltaic module manufacturing method according to claim 3 or 6, characterized in that, Steps (2-3) include: Step (3-1): Weld interconnecting strips (14) to each second electrode (1112) of the left end cell of the left sub-cell string (11) in each of the first back contact solar cell strings (100) and to each second electrode (1112) of the right end cell of the right sub-cell string (11); Weld interconnecting strips (14) to each first electrode (1111) of the left end cell of the left sub-cell string (11) in each of the second back contact solar cell strings (200) and to each first electrode (1111) of the right end cell of the right sub-cell string (11); Step (3-2): Connect the interconnecting strip (14) welded on the second electrode (1112) of the left end cell of the left sub-cell string (11) in each of the first back-contact solar cell strings (100) and the interconnecting strip (14) welded on the first electrode (1111) of the left end cell of the left sub-cell string (11) in the next adjacent second back-contact solar cell string (200) through an edge busbar (50) extending in the second direction; connect the interconnecting strip (14) welded on the second electrode (1112) of the right end cell of the right sub-cell string (11) in the first back-contact solar cell string (100) and the interconnecting strip (14) welded on the first electrode (1111) of the right end cell of the right sub-cell string (11) in the next adjacent second back-contact solar cell string (200) through an edge busbar (50) extending in the second direction. Step (3-3): Connect the intermediate busbar (13) in each of the second back-contact solar cell strings (200) and the intermediate busbar (13) in the next adjacent first back-contact solar cell string (100) via an electrical connector (60).

8. The method for manufacturing photovoltaic modules according to any one of claims 2-3 or 5-6, characterized in that, Electrically connecting all interconnecting bands between the right-end battery cell (111') and the left-end battery cell (111") to the intermediate busbar (13) extending along the second direction includes: A central busbar (13) is placed above all the interconnecting strips between the right end battery cell (111') and the left end battery cell (111") at a position corresponding to the insulating member (12), and the interconnecting strips are electrically connected to the central busbar (13) by welding; or, The central busbar (13) is inserted between the insulator (12) and all the interconnecting bands of the right end battery cell (111') and the left end battery cell (111"), and the interconnecting bands are electrically connected to the central busbar (13) by welding.

9. A photovoltaic module prepared according to the preparation method of any one of claims 1 to 8, characterized in that, The gap between the right end battery cell (111') and the left end battery cell (111") is equal to the gap between any two adjacent battery cells (111) in the sub-battery string (11).

10. The photovoltaic module according to claim 9, characterized in that, The photovoltaic module includes an insulating component (12) made of one or more of the following materials: a single-layer film or a multilayer film. PET, EVA, EVE, and POE; And / or, The width of the intermediate busbar (13) included in the photovoltaic module is smaller than the width of the insulating member (12); And / or, The intermediate busbar (13) of the photovoltaic module is a tin-coated copper strip or a conductive tape.

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