Photovoltaic module

Abstract

The embodiment of the present application relates to the field of photovoltaics, and provides a photovoltaic module, the photovoltaic module comprising a cell string connected by a plurality of back contact solar cells, the back contact solar cell comprising a cell body, a plurality of thin grids, a connecting line and a conductive part, the plurality of thin grids being located on the surface of one side of the cell body, and the thin grids extending along a first direction; the connecting line extending along a second direction, and the connecting line being electrically connected with each thin grid, the first direction intersecting the second direction; the conductive part extending along the second direction, the conductive part being electrically connected with the connecting line, and at least one conductive part of two adjacent back contact solar cells being electrically connected in the second direction. The solar cell provided by the embodiment of the present application can at least improve the photoelectric conversion efficiency of the photovoltaic module.

Description

Technical Field

[0001] This application relates to the field of photovoltaics, and in particular to a photovoltaic module. Background Technology

[0002] In the existing manufacturing of back-contact photovoltaic modules, since the electrodes of the back-contact cells are all located on the back side, it is necessary to apply insulating glue to isolate the positive and negative electrodes to prevent short circuits, and use solder paste as a connection bridge between the solder ribbon and the cell to ensure electrical connection. This process is not only cumbersome and increases production costs, but the presence of the solder ribbon will also block some light, affecting the photoelectric conversion efficiency of the module.

[0003] Therefore, there is an urgent need for a photovoltaic module that can solve the above problems. Summary of the Invention

[0004] This application provides a photovoltaic module that at least helps improve the photoelectric conversion efficiency of the photovoltaic module.

[0005] According to some embodiments of this application, one aspect of this application provides a photovoltaic module, including: a battery string, formed by connecting multiple back-contact solar cells, wherein each back-contact solar cell includes a cell body, multiple grids, connecting lines, and conductive portions, wherein the multiple grids are located on a surface on one side of the cell body, and the grids extend along a first direction; the connecting lines extend along a second direction and are electrically connected to each of the grids, the first direction intersects the second direction; the conductive portions extend along the second direction and are electrically connected to the connecting lines, wherein at least one conductive portion of two adjacent back-contact solar cells is electrically connected in the second direction.

[0006] In some embodiments, in a third direction, the conductive portion at least partially overlaps with the connecting line, wherein the third direction is perpendicular to the first direction and the second direction, respectively.

[0007] In some embodiments, the plurality of fine gates includes a plurality of first fine gates and a plurality of second fine gates, the first fine gates extending along the first direction, the second fine gates extending along the first direction, the first fine gates and the second fine gates being arranged alternately in the second direction, and the polarity of the second fine gates being different from the polarity of the first fine gates.

[0008] In some embodiments, in the first direction, the width of the conductive portion is less than or equal to the width of the connecting line.

[0009] In some embodiments, in the first direction, the photovoltaic module satisfies at least one of the following: the width of the conductive part is 0.1~0.2mm; the width of the connecting line is 0.1~0.2mm.

[0010] In some embodiments, the back-contact solar cell is a gridless back-contact solar cell.

[0011] In some embodiments, the thickness of the conductive portion is 5~20 μm.

[0012] In some embodiments, the material of the conductive portion includes copper.

[0013] In some embodiments, the conductive portion satisfies at least one of the following: at least one of the conductive portions of two adjacent back-contact solar cells is in direct contact; at least one of the connecting wires of two adjacent back-contact solar cells is electrically connected by conductive adhesive.

[0014] In some embodiments, the photovoltaic module further includes: a busbar extending along the first direction and electrically connected to at least one of the conductive portions; an encapsulating film for covering the surface of the battery string; and a cover plate for covering the surface of the encapsulating film facing away from the battery string.

[0015] The technical solution provided in this application has at least the following advantages:

[0016] Unlike traditional modules where solar cells are interconnected in strings via solder ribbons, in this application, the conductive parts of the cell strings are electrically connected to the connecting wires, enabling current collection and transmission. Furthermore, the conductive parts of adjacent cells are butt-joined or overlapped in a second direction to form an electrical connection, thereby connecting the currents of each cell in series. Therefore, during module fabrication, there is no need for PAD points, solder ribbons, solder paste, insulating adhesive, or other materials, simplifying the module fabrication process and reducing costs. It also reduces shading of the back-contact solar cells, improving photoelectric conversion efficiency. Attached Figure Description

[0017] One or more embodiments are illustrated by way of example with reference to the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Unless otherwise stated, the drawings in the accompanying drawings do not constitute a limitation on scale. In order to more clearly illustrate the technical solutions in the embodiments of this application or in the conventional art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the structure of a photovoltaic module provided in one embodiment of this application;

[0019] Figure 2This is a schematic diagram of another photovoltaic module provided in an embodiment of this application.

[0020] The above figures include the following reference numerals:

[0021] 10. Cell body; 11. Grid; 12. Connecting wire; 13. Conductive part; 111. First grid; 112. Second grid; 14. Conductive adhesive; 1. Cell string; 2. Busbar; 3. Encapsulating film; 4. Cover plate. Detailed Implementation

[0022] As is known from the background art, the presence of solder ribbon affects the photoelectric conversion efficiency of the module. This application provides a photovoltaic module including a cell string composed of multiple back-contact solar cells connected together. Each back-contact solar cell includes a cell body, multiple grids, connecting lines, and conductive portions. The multiple grids are located on a surface on one side of the cell body and extend along a first direction. The connecting lines extend along a second direction and are electrically connected to each grid. The first and second directions intersect. The conductive portions extend along the second direction and are electrically connected to the connecting lines. In the second direction, at least one conductive portion of each of two adjacent back-contact solar cells is electrically connected, which can at least improve the photoelectric conversion efficiency of the photovoltaic module.

[0023] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0024] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0025] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent three cases: A exists, A and B exist simultaneously, and B exists. In addition, the character " / " in this document generally indicates that the related objects before and after it have an "or" relationship.

[0026] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0027] In the description of the embodiments of this application, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0028] In the description of the embodiments of this application, unless otherwise expressly specified and limited, the technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0029] In the accompanying drawings corresponding to the embodiments of this application, the thickness and area of ​​the layers are enlarged for better understanding and ease of description. When describing a component (such as a layer, film, region, or substrate) on or on the surface of another component, the component may be "directly" located on the surface of the other component, or there may be a third component between the two components. Conversely, when describing a component on the surface of another component, or when another component is formed or disposed on the surface of a component, it indicates that there is no third component between the two components. Furthermore, when describing a component as being "generally" formed on another component, it means that the component is not formed on the entire surface (or front surface) of the other component, nor is it formed on a portion of the edge of the entire surface.

[0030] In the description of the embodiments of this application, when a component "includes" another component, other components are not excluded unless otherwise stated, and other components may be further included. Furthermore, when a component such as a layer, film, region, or plate is referred to as being "on / located" on another component, it can be "directly on" the other component (i.e., located on the surface of the other component with no other components between them), or another component may be present therein. Moreover, when a component such as a layer, film, region, or plate is "directly located" on another component, or when a component such as a layer, film, region, or plate is located on the surface of another component, it indicates that no other components are located therein.

[0031] The terminology used in the description of the various embodiments described herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used in the description of the various embodiments and the appended claims, the term "foreword" is also intended to include the plural form unless the context clearly indicates otherwise. Components include layers, films, regions, or plates, etc.

[0032] The embodiments of this application will now be described in detail with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details have been provided in the embodiments of this application to facilitate a better understanding of the application. However, the technical solutions claimed in this application can be implemented even without these technical details and various variations and modifications based on the following embodiments.

[0033] This application provides a photovoltaic module. Figure 1 An exemplary schematic diagram of a photovoltaic module provided in one embodiment of this application is shown, such as... Figure 1 As shown, the photovoltaic module mentioned above includes:

[0034] A battery string is formed by connecting multiple back-contact solar cells. The back-contact solar cells include a cell body 10, multiple grids 11, connecting wires 12, and conductive parts 13.

[0035] Back-contact solar cells refer to solar cells where both the PN junction and the metal contact are located on the same side of the cell (i.e., the back side), with no electrodes obstructing the front, thus maximizing the utilization of incident light. The cell body 10 refers to the silicon-based solar cell that has undergone semiconductor processes such as texturing, diffusion, coating, and etching. In practical applications, multiple back-contact solar cells can be arranged along the second direction D2.

[0036] The aforementioned plurality of fine grids 11 are located on the surface of one side of the battery cell body 10, and the fine grids 11 extend along the first direction D1;

[0037] The aforementioned fine grid 11 is a fine metal grid line for collecting photogenerated carriers, formed by screen printing and sintering silver paste, silver-coated copper paste, or copper paste. The fine grid 11 extends parallel to the first direction D1 and is arranged at intervals to collect the photogenerated current in the polarity region of the solar cell.

[0038] The aforementioned connecting line 12 extends along the second direction D2 and is electrically connected to each of the aforementioned fine grids 11. The aforementioned first direction D1 intersects with the aforementioned second direction D2.

[0039] The connecting line 12 extends along a second direction D2 perpendicular to the fine grid 11, forming an electrical connection with each fine grid 11 of the same polarity, for summing the current collected by the fine grid 11 and conducting it to the edge of the battery. The connecting line 12 can be made of silver paste, silver-coated copper paste, copper paste, or other conductive materials. In practical applications, the width of the connecting line 12 can be greater than the width of the fine grid 11 to provide a low-resistance current path. In some embodiments, the first direction D1 intersects the second direction D2, the fine grid 11 extends along the first direction D1, and the connecting line 12 and the conductive portion 13 extend along the second direction D2.

[0040] The conductive portion 13 extends along the second direction D2 and is electrically connected to the connecting line 12. In the second direction D2, at least one of the conductive portions 13 of two adjacent back-contact solar cells is electrically connected.

[0041] The conductive part 13 can be a metal conductive layer that is covered on the surface of the connecting line 12 by electroplating. The conductive part 13 is electrically connected to the connecting line 12 and electrically connected to the conductive part 13 of the adjacent cell in the second direction D2. It is used to replace the solder strip in the traditional module to realize the collection and transmission of current and the series connection between cells.

[0042] The photovoltaic module of this application includes a cell string composed of multiple back-contact solar cells connected together. Each back-contact solar cell includes a cell body, multiple fine grids, connecting wires, and conductive parts. The multiple fine grids are located on one side of the cell body and extend along a first direction. The connecting wires extend along a second direction and are electrically connected to each fine grid, with the first and second directions intersecting. The conductive parts extend along the second direction and are electrically connected to the connecting wires. In the second direction, at least one conductive part of each of two adjacent back-contact solar cells is electrically connected. Unlike traditional modules where cells are interconnected by solder ribbons, in the cell string of this application, the conductive parts are electrically connected to the connecting wires, enabling current collection and transmission. Furthermore, the conductive parts of two adjacent cells are butt-joined or overlapped in the second direction to form an electrical connection, thereby connecting the current of each cell in series. Therefore, during module fabrication, there is no need for PAD points, solder ribbons, solder paste, insulating adhesive, or other materials, which simplifies the module fabrication process, reduces costs, and minimizes shading of the back-contact solar cells, improving photoelectric conversion efficiency.

[0043] In some embodiments, in a third direction, the conductive portion at least partially overlaps with the connecting line, wherein the third direction is perpendicular to both the first and second directions. The above embodiments further define the spatial relationship between the conductive portion and the connecting line. By ensuring that the conductive portion and the connecting line at least partially overlap in a third direction, the conductive portion can directly cover the surface of the connecting line, forming a stable stacked electrode structure, ensuring the continuity and reliability of current transmission. Furthermore, the stacked structure allows for surface contact between the conductive portion and the connecting line, resulting in a larger contact area, lower contact resistance, and more uniform current distribution compared to line or point contact.

[0044] In specific implementation, the third direction refers to the normal direction of the cell surface, i.e., the direction perpendicular to the cell surface. In this direction, the conductive part and the connecting line at least partially overlap, meaning the conductive part covers the connecting line, forming a stacked structure in the direction perpendicular to the cell surface. The aforementioned "at least partially overlap" means that the projection of the conductive part in the third direction overlaps with the projection of the connecting line. This overlapping area can be that the conductive part completely covers the connecting line, i.e., the width of the conductive part is greater than or equal to the width of the connecting line; or it can be that the conductive part only covers a portion of the connecting line, i.e., the width of the conductive part is less than the width of the connecting line. In actual processes, the conductive part can completely cover the connecting line to ensure better electrical connection and current collection effect.

[0045] In the specific implementation process, such as Figure 1 As shown, the plurality of fine grids 11 include a plurality of first fine grids 111 and a plurality of second fine grids 112. The first fine grids 111 extend along the first direction D1, and the second fine grids 112 extend along the first direction D1. In the second direction D2, the first fine grids 111 and the second fine grids 112 are arranged alternately, and the polarity of the second fine grids 112 is different from that of the first fine grids 111. By using alternating arrangements of first fine grids 111 and second fine grids 112 of different polarities on the battery surface, physical separation of the positive and negative electrode grids can be achieved, effectively avoiding electrode short circuits.

[0046] The first fine gate 111 is either a P-type fine gate or an N-type fine gate, and the second fine gate 112 is the other. Both extend along the first direction D1 and are alternately arranged with connecting lines in the second direction D2 to form an interdigitated electrode pattern. The aforementioned alternating arrangement means that the first fine gate 111 and the second fine gate 112 appear alternately in the second direction D2, and a certain distance is maintained between adjacent first fine gates 111 and second fine gates 112 to achieve physical isolation between the positive and negative electrodes and prevent short circuits.

[0047] In other embodiments, in the first direction, the width of the conductive portion is less than or equal to the width of the connecting line. That is, the conductive portion is entirely within the projection range of the connecting line in the width direction and does not extend beyond the edge of the connecting line. This design allows the stacked structure of the conductive portion and the connecting line to have a cross-sectional shape where the conductive portion completely covers the surface of the connecting line or is recessed into the surface of the connecting line. This facilitates control of the metal shielding area and ensures that the conductive portion is accurately formed above the connecting line during electroplating or deposition.

[0048] When the widths of the conductive part and the connecting line are equal, the edge of the conductive part is aligned with the edge of the connecting line; when the width of the conductive part is less than the width of the connecting line, the edge of the conductive part is recessed into the edge of the connecting line.

[0049] In some embodiments, in the first direction described above, the photovoltaic module satisfies at least one of the following: the width of the conductive portion is 0.1 to 0.2 mm; the width of the connecting line is 0.1 to 0.2 mm. Controlling the width of the conductive portion and / or the connecting line within the range of 0.1 to 0.2 mm can minimize the metal shading area and further reduce optical losses while maintaining sufficient current transmission capacity.

[0050] The first direction mentioned above is the direction of fine grid extension, in which both the conductive part and the connecting line have a certain width. The width of the conductive part and the connecting line is narrower than the width of the main grid or solder strip in a conventional back contact battery (typically 0.3~0.5mm). By controlling the width of the conductive part (copper strip) and the connecting line within this range, a balance can be achieved between current transmission capacity and light-shielding area.

[0051] In some embodiments, the aforementioned back-contact solar cell is a gridless back-contact solar cell. By completely eliminating the traditional grid structure and relying solely on fine grids, connecting lines, and conductive parts for current collection, the metal shading area on the front of the cell can be reduced, thereby increasing the short-circuit current density and further improving the photoelectric conversion efficiency of the back-contact solar cell module.

[0052] Zero Busbar (OBB) structure refers to a solar cell structure that does not have a main grid electrode with a width significantly larger than the fine grid on its surface. Only the fine grid and the connecting lines used to collect the current from the fine grid are retained. These connecting lines are thinner than those of a traditional main grid and function differently. Current flows directly into the connecting lines through the fine grid and is then discharged through conductive parts plated on the connecting lines, eliminating the need for a traditional main grid as an intermediate current collection point.

[0053] In other embodiments, the thickness of the conductive portion is 5 to 20 μm. A thickness of 5 to 20 μm balances low resistance and process compatibility, achieving the lowest series resistance without increasing material costs, thereby further improving the photoelectric conversion efficiency of the photovoltaic module.

[0054] The third direction is the normal to the surface of the solar cell, and the dimension of the conductive part in this direction is the thickness. The above-mentioned thickness range can balance conductivity, process feasibility, and reliability. When the thickness is less than 5μm, the conductive cross-sectional area of ​​the copper layer is insufficient, resulting in high resistance; when the thickness is greater than 20μm, the internal stress of the copper layer increases, which may lead to cell warping or copper layer peeling.

[0055] In some embodiments, the conductive portion is made of copper. Using copper as the conductive portion material, instead of the solder-clad copper or aluminum used in conventional solder strips, results in lower costs. For the same cross-sectional area, the resistance of the copper conductive portion is approximately 30% lower than that of conventional solder strips, thereby further reducing component power loss.

[0056] In practical applications, copper has excellent electrical conductivity and relatively low cost, making it a viable alternative to traditional solder strip materials. The material of the aforementioned conductive part, including copper, refers to the fact that the main conductive component of the conductive part is copper. This can be pure copper, copper alloys (such as copper-silver alloys, copper-tin alloys), or a composite layer with copper as the main component. The conductive part can be a single copper layer or a multi-layer structure (such as a copper-nickel composite layer or a copper-tin composite layer), as long as its main conductive material is copper.

[0057] In other implementations, such as Figure 1 As shown, the conductive portion 13 satisfies at least one of the following: at least one of the conductive portions 13 of two adjacent back-contact solar cells is in direct contact; at least one of the connecting lines 12 of two adjacent back-contact solar cells is electrically connected through conductive adhesive 14. Using direct contact of the conductive portions 13 requires no additional materials, simplifies the process, reduces costs, and provides reliable fixation and insulation protection after lamination. Furthermore, using conductive adhesive 14 instead of traditional solder ribbon and solder paste enables low-temperature and non-molten interconnection, avoiding thermal damage to the solar cells caused by high-temperature soldering, making it particularly suitable for thin silicon wafer solar cells.

[0058] There are two specific methods for achieving electrical connection between adjacent solar cells: one is through direct contact of the conductive parts 13 of adjacent solar cells; the other is through electrical connection of the connecting wires 12 of adjacent solar cells via conductive adhesive 14. Direct contact of the conductive parts 13 means that the conductive parts 13 of two adjacent solar cells are butt-to-button or partially overlap at the gap between the cells, forming an electrical connection through physical contact. This method requires no additional connecting materials and is simple to implement. During lamination, the encapsulating film flows to fill the gaps, fixing the conductive parts 13 together.

[0059] Furthermore, the aforementioned conductive adhesive 14 refers to an adhesive with conductive properties, which can be formed by dispersing conductive fillers (such as silver powder, copper powder, nickel powder, carbon nanotubes, graphene, etc.) in a resin matrix (such as epoxy resin, acrylic resin, silicone resin, etc.). After the conductive adhesive 14 cures, a conductive network is formed between the conductive fillers, achieving electrical connection, while the resin matrix provides mechanical bonding strength. In addition, the bonding process of the conductive adhesive 14 can be achieved through dispensing, printing, or lamination.

[0060] like Figure 2 As shown, the photovoltaic module further includes: a busbar 2 extending along the first direction and electrically connected to at least one conductive part; an encapsulating film 3 covering the surface of the cell string 1; and a cover plate 4 covering the surface of the encapsulating film 3 facing away from the cell string 1. The busbar 2 directly connects to the copper-plated conductive part of the cell, replacing the traditional tin-clad copper solder strip and pad structure, achieving low-resistance copper-copper interconnection, significantly reducing contact resistance and minimizing module power loss. Simultaneously, it eliminates the need for PAD points on the cell to connect the solder strip, simplifying cell design and further increasing the effective light-receiving area of ​​the cell. In practical applications, the busbar 2 structure can be flexibly arranged according to the module's circuit design requirements (such as half-cell, shingled, etc.) to adapt to different module types. Furthermore, the encapsulating film 3 and cover plate 4 further ensure the module's mechanical strength, environmental sealing, and electrical insulation, enabling the module to operate stably for extended periods in harsh outdoor environments.

[0061] Busbar 2 is a conductive strip extending along the first direction, located at the end or middle of the battery string 1, intersecting and electrically connecting with multiple conductive sections. The width of busbar 2 can be 1~5mm, the thickness can be 0.1~0.3mm, and the material can be copper strip, copper foil, or tin-plated copper strip, etc. Busbar 2 is used to collect the current from multiple battery strings 1 and conduct it to the junction box of the module. Encapsulating film 3 is a polymer film material used to encapsulate and protect the battery string 1, and can be made of materials such as ethylene-vinyl acetate copolymer (EVA), polyvinyl butyral (PVB), or polyolefin elastomer (POE). Encapsulating film 3 melts and solidifies during lamination, bonding the battery cells to the cover plate 4 and backplate, while providing electrical insulation and environmental protection. The cover plate 4 is a transparent protective material covering the outermost layer of the module. It can be tempered glass or transparent organic materials, such as ethylene-tetrafluoroethylene copolymer (ETFE) or fluorinated ethylene-propylene copolymer (FEP), to protect the internal cells from mechanical damage and environmental corrosion, while ensuring high transmittance of incident light.

[0062] As can be seen from the above description, the embodiments of this application achieve the following technical effects:

[0063] The photovoltaic module of this application includes a cell string composed of multiple back-contact solar cells connected together. Each back-contact solar cell includes a cell body, multiple fine grids, connecting wires, and conductive parts. The multiple fine grids are located on one side of the cell body and extend along a first direction. The connecting wires extend along a second direction and are electrically connected to each fine grid, with the first and second directions intersecting. The conductive parts extend along the second direction and are electrically connected to the connecting wires. In the second direction, at least one conductive part of each of two adjacent back-contact solar cells is electrically connected. Unlike traditional modules where cells are interconnected by solder ribbons, in the cell string of this application, the conductive parts are electrically connected to the connecting wires, enabling current collection and transmission. Furthermore, the conductive parts of two adjacent cells are butt-joined or overlapped in the second direction to form an electrical connection, thereby connecting the current of each cell in series. Therefore, during module fabrication, there is no need for PAD points, solder ribbons, solder paste, insulating adhesive, or other materials, which simplifies the module fabrication process, reduces costs, and minimizes shading of the back-contact solar cells, improving photoelectric conversion efficiency.

[0064] Those skilled in the art will understand that the above embodiments are specific examples of implementing this application, and in practical applications, various changes in form and detail can be made without departing from the spirit and scope of this application. Any person skilled in the art can make various alterations and modifications without departing from the spirit and scope of this application; therefore, the scope of protection of this application should be determined by the scope defined in the claims.

Claims

1. A photovoltaic module, characterized in that, include: A battery string is composed of multiple back-contact solar cells connected together. Each back-contact solar cell includes a cell body, multiple fine grids, connecting wires, and conductive parts. The plurality of fine grids are located on the surface of one side of the battery cell body, and the fine grids extend along a first direction; The connecting line extends along the second direction and is electrically connected to each of the fine gates, wherein the first direction intersects the second direction; The conductive portion extends along the second direction and is electrically connected to the connecting line. In the second direction, at least one of the conductive portions of two adjacent back-contact solar cells is electrically connected.

2. The photovoltaic module according to claim 1, characterized in that, In the third direction, the conductive portion at least partially overlaps with the connecting line, wherein the third direction is perpendicular to the first direction and the second direction, respectively.

3. The photovoltaic module according to claim 1, characterized in that, The plurality of fine gates includes a plurality of first fine gates and a plurality of second fine gates, the first fine gates extending along the first direction, the second fine gates extending along the first direction, the first fine gates and the second fine gates being arranged alternately in the second direction, and the polarity of the second fine gates being different from that of the first fine gates.

4. The photovoltaic module according to claim 1, characterized in that, In the first direction, the width of the conductive part is less than or equal to the width of the connecting line.

5. The photovoltaic module according to claim 1, characterized in that, In the first direction, the photovoltaic module satisfies at least one of the following: The width of the conductive part is 0.1~0.2mm; The width of the connecting line is 0.1~0.2mm.

6. The photovoltaic module according to claim 1, characterized in that, The back-contact solar cell is a gridless back-contact solar cell.

7. The photovoltaic module according to claim 1, characterized in that, The thickness of the conductive part is 5~20μm.

8. The photovoltaic module according to claim 1, characterized in that, The material of the conductive part includes copper.

9. The photovoltaic module according to claim 1, characterized in that, The conductive portion satisfies at least one of the following: At least one of the conductive portions of two adjacent back-contact solar cells is in direct contact; At least one of the connecting wires of two adjacent back-contact solar cells is electrically connected by conductive adhesive.

10. The photovoltaic module according to claim 1, characterized in that, The photovoltaic module also includes: A busbar extending along the first direction and electrically connected to at least one of the conductive portions; An encapsulating film is used to cover the surface of the battery string; A cover plate is used to cover the surface of the encapsulating film that faces away from the battery string.

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