Solar cell and photovoltaic module

Abstract

The application discloses a solar cell and a photovoltaic module, and belongs to the technical field of photovoltaic modules. The solar cell comprises a substrate; a transmission electrode, which is arranged on the surface of the substrate and is electrically connected with the substrate, and a plurality of protruding parts arranged in sequence on the side of the transmission electrode away from the substrate, wherein the plurality of protruding parts are arranged in an array, and adjacent protruding parts are at least partially connected.

Description

Technical Field

[0001] This application relates to the field of photovoltaic module technology, specifically to a solar cell and a photovoltaic module. Background Technology

[0002] With the rapid development of the photovoltaic industry, competition is becoming increasingly fierce, and the cost of photovoltaic modules has attracted widespread attention. Solar cells, as the core component of photovoltaic modules, convert solar energy into electrical energy. A solar cell consists of a substrate and transmission electrodes disposed on the surface of the substrate. These transmission electrodes collect the current generated by the substrate and transmit it to an external circuit.

[0003] In related technologies, base metal pastes are used to prepare transmission electrodes in order to reduce the cost of solar cells. For example, the base metal can be copper, aluminum, etc.

[0004] However, in the photovoltaic industry, how to further reduce the cost of transmission electrodes while ensuring current transmission efficiency remains a pressing issue. Summary of the Invention

[0005] This application discloses a solar cell and a photovoltaic module to solve, or at least partially solve, the problems existing in the prior art, such as the high cost of transmission electrodes and the inability to guarantee current transmission efficiency.

[0006] To solve the above-mentioned technical problems, this application is implemented as follows:

[0007] In a first aspect, this application discloses a solar cell, the solar cell including a substrate; a transmission electrode disposed on the surface of the substrate and electrically connected to the substrate, wherein a plurality of protrusions are sequentially disposed on the side of the transmission electrode away from the substrate, the plurality of protrusions are arranged in an array, and adjacent protrusions are at least partially connected.

[0008] Optionally, the protrusions include multiple groups, and the multiple groups of protrusions are arranged sequentially along a first direction; each group of protrusions includes multiple protrusions, and the multiple protrusions are arranged sequentially along a second direction; wherein, the extension direction of the transmission electrode is a third direction, the second direction intersects the third direction, and the first direction intersects the second direction and the third direction.

[0009] Optionally, the second direction and the third direction have a first included angle, which is greater than or equal to 0 degrees and less than or equal to 60 degrees.

[0010] Optionally, the first included angle is greater than or equal to 0 degrees and less than or equal to 45 degrees.

[0011] Optionally, there is a second angle between the first direction and the second direction, and the second angle is less than or equal to 90 degrees.

[0012] Optionally, adjacent protrusions enclose a first region, and the transmission electrode corresponding to the first region is a recess.

[0013] Optionally, along the thickness direction of the solar cell, the height of the protrusion is greater than or equal to 5 μm and less than or equal to 30 μm; the height of the protrusion is the distance between the top of the protrusion and the recess.

[0014] Optionally, along the thickness direction of the solar cell, the height of the protrusion is greater than or equal to 5 μm and less than or equal to 15 μm.

[0015] Optionally, the projection of the protrusion onto the plane of the base is at least one of a cross-shaped structure, a hexagonal structure, or a triangular structure.

[0016] Optionally, the line connecting the center points of each group of protrusions lies on a straight line.

[0017] Optionally, the recessed portion includes multiple recesses, which are arranged in an array.

[0018] Optionally, the recessed portion includes a first recessed portion and a second recessed portion, the area of ​​the second recessed portion being a multiple of the area of ​​the first recessed portion; and / or, the protruding portion includes a first protruding portion and a second protruding portion, the area of ​​the second protruding portion being a multiple of the area of ​​the first protruding portion.

[0019] Optionally, the distance between the center points of two adjacent recesses is greater than or equal to 20 μm and less than or equal to 100 μm.

[0020] Optionally, along the thickness direction of the solar cell, the recess has a first depth relative to the top of the protrusion, and the ratio of the first depth to the distance between the center points of two adjacent recesses is greater than or equal to 0.1 and less than or equal to 1.

[0021] Optionally, along the thickness direction of the solar cell, the sum of the thickness of the transmission electrode corresponding to the protrusion and the thickness of the protrusion is greater than or equal to 9 μm and less than or equal to 50 μm; and / or, along the thickness direction of the solar cell, the thickness of the transmission electrode corresponding to the recess is greater than or equal to 1 μm and less than or equal to 20 μm.

[0022] Optionally, the projection of the recessed portion onto the plane of the substrate is at least one of a circular structure, an elliptical structure, a square structure, or a near-square structure.

[0023] Optionally, the transmission electrodes include a plurality of electrodes, each extending along a third direction and spaced apart along a fourth direction; wherein the fourth direction intersects the third direction.

[0024] Optionally, the solar cell further includes: a passivation layer stacked between the substrate and the transmission electrode; and a contact electrode passing through the passivation layer, with one end of the contact electrode electrically connected to the substrate and the other end of the contact electrode electrically connected to the transmission electrode.

[0025] Optionally, the transmission electrode has a first projection on the plane where the substrate is located, and the contact electrode has a second projection on the plane where the substrate is located, the second projection falling within the first projection.

[0026] Optionally, along the fourth direction, the width of the transmission electrode is greater than or equal to 60 μm; and / or, along the fourth direction, the width of the contact electrode is greater than or equal to 10 μm and less than or equal to 40 μm.

[0027] Optionally, the substrate has a first surface and a second surface disposed opposite to each other, the passivation layer is stacked on the first surface of the substrate, and / or the passivation layer is stacked on the second surface of the substrate.

[0028] Optionally, along the second direction, the distance between the center points of two adjacent protrusions is W1; along the fourth direction, the width of the contact electrode is W2, satisfying -2 < lg(W2 / W1) < 2; wherein, the second direction intersects the third direction, and the fourth direction is perpendicular to the third direction.

[0029] Optionally, -1 < lg(W2 / W1) < 1 is satisfied.

[0030] Optionally, W2 ≥ 30 μm must be satisfied.

[0031] Optionally, W1 < 2W2 must be satisfied.

[0032] Optionally, the distance between the center points of two adjacent recesses is W3, and the width of the contact electrode along the fourth direction is W2, satisfying W2-W3>10μm.

[0033] Optionally, the substrate includes a first surface and a second surface disposed opposite to each other, the second surface having a first electrode region and a second electrode region disposed adjacent to each other, the first electrode region and the second electrode region having opposite polarities; the transmission electrode includes a first transmission electrode and a second transmission electrode, the first transmission electrode being disposed in the first electrode region and electrically connected to the first electrode region, the second transmission electrode being disposed in the second electrode region and electrically connected to the second electrode region; wherein, along the thickness direction of the solar cell, the height of the protrusion in the first transmission electrode is the same as or different from the height of the protrusion in the second transmission electrode.

[0034] Optionally, the distance between the center points of two adjacent recesses in the first transmission electrode is different from the distance between the center points of two adjacent recesses in the second transmission electrode.

[0035] Secondly, this application discloses a photovoltaic module comprising the solar cells described in the first aspect.

[0036] This application discloses a solar cell and a photovoltaic module. The solar cell includes a substrate and a transmission electrode. The transmission electrode is disposed on the surface of the substrate and electrically connected to the substrate. A plurality of protrusions are sequentially disposed on the side of the transmission electrode away from the substrate. The plurality of protrusions are arranged in an array, and adjacent protrusions are at least partially connected.

[0037] In this application, multiple protrusions are sequentially arranged on the side of the transfer electrode away from the substrate, and these protrusions are arranged in an array. That is, the area formed between adjacent protrusions on the transfer electrode 40 is a recess. This arrangement reduces the amount of transfer electrode material used and lowers the cost of the transfer electrode.

[0038] Furthermore, in this application, multiple protrusions are arranged in an array, and adjacent protrusions are at least partially connected, which can also ensure the current transmission efficiency of the transmission electrode, reduce the power loss of the transmission electrode, and ensure the photoelectric conversion efficiency of the solar cell. Attached Figure Description

[0039] Figure 1 This diagram illustrates the structure of the solar cell described in the embodiments of this application. Figure 1 ;

[0040] Figure 2 This diagram illustrates the structure of the solar cell described in the embodiments of this application. Figure 2 ;

[0041] Figure 3 This diagram illustrates the structure of the solar cell described in the embodiments of this application. Figure 3 ;

[0042] Figure 4 This diagram illustrates the structure of the solar cell described in the embodiments of this application. Figure 4 ;

[0043] Figure 5 This diagram illustrates the structure of the solar cell described in the embodiments of this application. Figure 5 ;

[0044] Figure 6 This diagram illustrates the structure of the solar cell described in the embodiments of this application. Figure 6 ;

[0045] Figure 7 This is a side view of the solar cell described in an embodiment of this application;

[0046] Figure 8 This is a schematic diagram showing the structure of the contact electrode described in the embodiments of this application.

[0047] Figure label:

[0048] 10: Base;

[0049] 20: Passivation layer;

[0050] 30: Contact electrode;

[0051] 40: Transmission electrode; 41: Protrusion; 411: First protrusion; 412: Second protrusion; 42: Connecting part; 43: Recess; 431: First recess; 432: Second recess;

[0052] A: First direction; B: Second direction; C: Third direction; D: Fourth direction. Detailed Implementation

[0053] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of the present invention.

[0054] It should be understood that the phrase "one embodiment" or "an embodiment" throughout the specification means that a specific feature, structure, or characteristic related to the embodiment is included in at least one embodiment of the invention. Therefore, "in one embodiment" or "in an embodiment" appearing throughout the specification do not necessarily refer to the same embodiment. Furthermore, these specific features, structures, or characteristics can be combined in any suitable manner in one or more embodiments.

[0055] Reference Figure 1The diagram illustrates the structure of the solar cell described in the embodiments of this application. Figure 1 ;reference Figure 2 The diagram illustrates the structure of the solar cell described in the embodiments of this application. Figure 2 ;reference Figure 3 The diagram illustrates the structure of the solar cell described in the embodiments of this application. Figure 3 ;reference Figure 4 The diagram illustrates the structure of the solar cell described in the embodiments of this application. Figure 4 ;reference Figure 5 The diagram illustrates the structure of the solar cell described in the embodiments of this application. Figure 5 ;reference Figure 6 The diagram illustrates the structure of the solar cell described in the embodiments of this application. Figure 6 ;reference Figure 7 A side view of the solar cell described in an embodiment of this application is shown; refer to Figure 8 The diagram shows a schematic representation of the contact electrode in an embodiment of this application.

[0056] like Figures 1 to 8 As shown in the figure, this application discloses a solar cell, which includes a substrate 10 and a transmission electrode 40. The transmission electrode 40 is disposed on the surface of the substrate 10 and electrically connected to the substrate 10. A plurality of protrusions 41 are sequentially disposed on the side of the transmission electrode 40 away from the substrate 10. The plurality of protrusions 41 are arranged in an array, and adjacent protrusions 41 are at least partially connected.

[0057] This application discloses a solar cell comprising a substrate 10 and a transmission electrode 40. The substrate 10 absorbs solar energy and converts it into electrical energy. The substrate 10 can be P-type, N-type, or a silicon wafer of a near-intrinsic conductivity type. The crystal type of the substrate 10 can be monocrystalline or polycrystalline. In this application embodiment, no excessive restrictions are placed on the specific type of the substrate 10. In practical applications, those skilled in the art can choose according to their needs.

[0058] The substrate 10 in this embodiment has a first surface and a second surface disposed opposite to each other. The first surface can be a sun-receiving surface facing the sunlight, also known as the front surface. The first surface can also be a shadow-receiving surface facing away from the sunlight, also known as the back surface. When the first surface is the front surface, the second surface is the back surface. When the first surface is the back surface, the second surface is the front surface.

[0059] The following will use the first surface of the substrate 10 as the front side and the second surface as the back side as an example to describe the relevant embodiments of this application.

[0060] like Figures 1 to 8As shown, in this embodiment, the transmission electrode 40 is disposed on the surface of the substrate 10 and electrically connected to the substrate 10 to collect the current generated by the substrate 10. It should be noted that the transmission electrode 40 may be disposed only on the second surface of the substrate 10, meaning the solar cell is a back-contact solar cell. Alternatively, the transmission electrode 40 may be disposed on both the first and second surfaces of the substrate 10, meaning the solar cell is a bifacial cell.

[0061] In this embodiment, a plurality of protrusions 41 are sequentially arranged on the side of the transmission electrode 40 away from the substrate 10. These protrusions 41 are arranged in an array, and adjacent protrusions 41 are at least partially connected. In other words, the area formed between adjacent protrusions 41 on the transmission electrode 40 is a recess 43. This arrangement reduces the amount of material used in the transmission electrode 40, thereby reducing its cost.

[0062] Furthermore, in this embodiment, the multiple protrusions 41 are arranged in an array, and adjacent protrusions 41 are at least partially connected, which can also ensure the current transmission efficiency of the transmission electrode, reduce the power loss of the transmission electrode 40, and ensure the photoelectric conversion efficiency of the solar cell.

[0063] It should be noted that the transmission electrode 40 in this embodiment is made of a base metal. This base metal can be copper, aluminum, or other metals that are cheaper than copper or aluminum.

[0064] like Figures 1 to 4 As shown, the multiple protrusions 41 in this embodiment have the same structure and are arranged in an array on the side of the transmission electrode 40 away from the substrate 10. This not only reduces the amount of material used in the transmission electrode 40 and lowers the manufacturing cost of the transmission electrode 40, thereby reducing the cost of the solar cell and enhancing its market competitiveness, but also ensures the current transmission efficiency of the transmission electrode 40 and the photoelectric conversion efficiency of the solar cell.

[0065] It should be noted that in the embodiments of this application, the structures of the multiple protrusions 41 can be completely identical. For example, the multiple protrusions 41 can all be cross-shaped structures. The structures of the multiple protrusions 41 can also be partially identical. For example, some of the multiple protrusions 41 can be cross-shaped structures, while others can have other structures.

[0066] Optionally, such as Figures 1 to 6As shown, the protrusion 41 in this embodiment includes multiple groups, and the multiple groups of protrusions 41 are arranged sequentially along the first direction A; each group of protrusions 41 includes multiple protrusions, and the multiple protrusions 41 are arranged sequentially along the second direction B; wherein, the extension direction of the transmission electrode 40 is the third direction C, the second direction B intersects the third direction C, and the first direction A intersects the second direction B and the third direction C.

[0067] like Figures 1 to 6 As shown, the protrusions 41 in this embodiment include multiple groups, each group of protrusions 41 including multiple protrusions, and the multiple groups of protrusions 41 are arranged sequentially along the first direction A. The multiple protrusions 41 in each group are arranged sequentially along the second direction B. The first direction A may be the same as the extension direction of the transmission electrode 40, i.e., the third direction C. The first direction A may also have an angle with the extension direction of the transmission electrode 40, which is typically an acute angle. The second direction B intersects the first direction A; exemplarily, the second direction B is perpendicular to the first direction A.

[0068] In this embodiment, multiple sets of protrusions 41 are arranged sequentially along a first direction A, and multiple protrusions 41 in each set are arranged sequentially along a second direction B, so that the multiple protrusions 41 are arranged in an array on the side of the transmission electrode 40 away from the substrate 10. The arrayed arrangement of multiple protrusions 41 not only reduces the amount of material used in the transmission electrode 40 and lowers the manufacturing cost of the transmission electrode 40, thereby reducing the cost of the solar cell and enhancing its market competitiveness, but also ensures the current transmission efficiency of the transmission electrode 40 and the photoelectric conversion efficiency of the solar cell.

[0069] Optionally, such as Figure 3 As shown in the embodiment of this application, there is a first included angle between the second direction B and the third direction C, which is greater than or equal to 0 degrees and less than or equal to 60 degrees.

[0070] like Figure 3 As shown in the embodiment of this application, the first angle between the second direction B and the third direction C is set to be greater than or equal to 0 degrees and less than or equal to 60 degrees, so that the extension direction of each set of protrusions 41 has an angle of less than or equal to 60 degrees with the extension direction of the transmission electrode 40, thereby further enhancing the current transmission capability of the transmission electrode 40 and improving the photoelectric conversion efficiency of the solar cell.

[0071] For example, the first included angle between the second direction B and the third direction C can be set to 0°, 10°, 20°, 30°, 40°, 50°, 60°, etc.

[0072] In a preferred embodiment of this application, the first included angle can be set to be greater than or equal to 0 degrees and less than or equal to 45 degrees. This ensures that the extension direction of each set of protrusions 41 has an angle of less than or equal to 45 degrees with the extension direction of the transmission electrode 40, thereby further increasing the current transmission capability of the transmission electrode 40 and improving the photoelectric conversion efficiency of the solar cell.

[0073] For example, the first included angle between the second direction B and the third direction C can be set to 0°, 15°, 25°, 35°, 45°, etc.

[0074] As a preferred embodiment, such as Figure 3 As shown in the embodiment of this application, there is a second included angle between the first direction A and the second direction B, and the second included angle is less than or equal to 90 degrees.

[0075] In this embodiment, the second included angle between the first direction A and the second direction B is set to be less than or equal to 90 degrees. Taking a 90-degree second included angle between the first direction and the second direction B as an example, this means that the first direction A is perpendicular to the second direction B. This arrangement allows adjacent groups of protrusions 41 to be arranged in a direction perpendicular to the extension direction of each group of protrusions 41. This results in more protrusions 41 being located on the side of the transmission electrode 40 away from the substrate 10, further improving the current transmission efficiency of the transmission electrode 40, reducing the amount of material used in the transmission electrode 40, and enhancing the market competitiveness of the solar cell.

[0076] Of course, the above arrangement also makes the connection between adjacent protrusions 41 more reliable, thereby helping to improve the current transmission efficiency of the transmission electrode 40 and the photoelectric conversion efficiency of the solar cell. It avoids the situation where adjacent protrusions 41 are not connected, which would affect the transmission efficiency of the solar cell.

[0077] For example, the second included angle between the first direction A and the second direction B can be 90 degrees, 85 degrees, 80 degrees, 75 degrees, 70 degrees, 65 degrees, etc.

[0078] Optionally, such as Figures 1 to 6 As shown, in this embodiment of the application, adjacent protrusions 41 enclose a first region, and the transmission electrode 40 corresponding to the first region is a recess 43.

[0079] In the embodiments of this application, such as Figures 1 to 6 As shown, adjacent protrusions 41 enclose a first region, and the transmission electrode 40 corresponding to the first region is a recess 43. The recess 43 can reduce the amount of material used in the transmission electrode 40, reduce the cost of the transmission electrode 40, thereby helping to reduce the cost of solar cells and enhance the market competitiveness of solar cells.

[0080] Taking the protrusion 41 as a cross-shaped structure as an example, two adjacent protrusions 41 along the first direction A and two protrusions 41 opposite to the two protrusions 41 along the second direction B can enclose and form a first region. The transmission electrode 40 corresponding to this first region is a recess 43. It can be understood that the transmission electrode 40 has multiple first regions, that is, the transmission electrode 40 has multiple recesses 43.

[0081] Optionally, along the thickness direction of the solar cell, the height of the protrusion 41 is greater than or equal to 5 μm and less than or equal to 30 μm, and the height of the protrusion 41 is the distance between the top of the protrusion 41 and the recess 43.

[0082] In this embodiment, the height of the protrusion 41 is set to be greater than or equal to 5 μm and less than or equal to 30 μm along the thickness direction of the solar cell. This setting not only reduces the amount of material used in the transmission electrode 40 and lowers the manufacturing cost of the transmission electrode 40, thereby helping to reduce the cost of the solar cell and enhance its market competitiveness, but also enables the transmission electrode 40 to have higher transmission efficiency, ensuring the photoelectric conversion efficiency of the solar cell.

[0083] For example, the height of the protrusion 41 can be set to 5μm, 8μm, 10μm, 15μm, 20μm, 25μm, 30μm, etc. along the thickness direction of the solar cell.

[0084] In a preferred embodiment, the height of the protrusion 41 can be set to be greater than or equal to 5 μm and less than or equal to 15 μm along the thickness direction of the solar cell. This setting can further reduce the amount of material used in the transmission electrode 40, thus reducing the manufacturing cost of the transmission electrode 40. Simultaneously, it enables the transmission electrode 40 to have higher current transmission efficiency, thereby ensuring the photoelectric conversion efficiency of the solar cell.

[0085] For example, the height of the protrusion 41 can be set to 5μm, 7μm, 9μm, 10μm, 12μm, 14μm, 15μm, etc. along the thickness direction of the solar cell.

[0086] In this embodiment, the height of the protrusion 41 is set to be greater than or equal to 5 μm and less than or equal to 15 μm along the thickness direction of the solar cell. This further reduces the amount of material used in the transmission electrode 40, reduces the manufacturing cost of the transmission electrode 40, and ensures that the transmission electrode 40 has a high current transmission capability to guarantee the photoelectric conversion efficiency of the solar cell.

[0087] Optionally, such as Figures 1 to 6As shown, in the embodiments of this application, the projection of the protrusion 41 onto the plane of the base 10 is at least one of a cross-shaped structure, a hexagonal structure, and a triangular structure.

[0088] like Figures 1 to 6 As shown, in this embodiment, the protrusion 41 has a projection onto the plane of the base 10. This projection includes, but is not limited to, one or more of a cross-shaped structure, a hexagonal structure, and a triangular structure. That is, the projection of the protrusion 41 onto the plane of the base 10 may include only a cross-shaped structure, or only a hexagonal structure, or only a triangular structure. The projection of the protrusion 41 onto the plane of the base 10 may include a cross-shaped structure and a hexagonal structure, or the projection of the protrusion 41 onto the plane of the base 10 may include a cross-shaped structure and a triangular structure, or the projection of the protrusion 41 onto the plane of the base 10 may also include a hexagonal structure and a triangular structure.

[0089] Of course, the above are merely individual examples of embodiments of this application and are not intended to limit the scope of this application. In practical applications, those skilled in the art can customize the specific structure of the protrusion 41 as needed.

[0090] In this embodiment, the projection of the protrusion 41 onto the plane of the substrate 10 is set as at least one of a cross-shaped structure, a hexagonal structure, and a triangular structure. These structures have multiple connecting edges around the center point to facilitate the connection of adjacent protrusions 41, thereby reducing the power loss of the transmission electrode 40, improving the current transmission efficiency of the transmission electrode 40, and ensuring the photoelectric conversion efficiency of the solar cell.

[0091] Furthermore, the above-mentioned configuration can reduce the amount of material used in the transmission electrode 40, reduce the manufacturing cost of the transmission electrode 40, thereby reducing the cost of the solar cell and enhancing its market competitiveness.

[0092] like Figures 1 to 6 As shown, when the projection of the protrusion 41 onto the plane of the substrate 10 forms a cross shape, multiple connecting portions 42 can be sequentially arranged on the side of the transmission electrode 40 away from the substrate 10. Each connecting portion 42 connects two adjacent protrusions 41, thereby increasing the current transmission path of the transmission electrode 40. When poor contact occurs in some areas of the transmission electrode 40, or when the resistance of some areas of the transmission electrode 40 is high, the current can be transmitted along the path with lower resistance, thereby reducing the current transmission distance and improving the current transmission efficiency of the transmission electrode 40.

[0093] Taking the protrusion 41 as a cross-shaped structure as an example, the connecting part 42 can be a ridge strip, which connects adjacent protrusions 41. The extension line of the ridge strip connecting the two opposite vertices of the protrusion 41 points to the center of the protrusion 41.

[0094] Optionally, such as Figures 1 to 6 As shown in the embodiment of this application, the connecting line of the center points of each group of protrusions 41 is on a straight line.

[0095] like Figures 1 to 6 As shown in the embodiment of this application, the connecting line of the center point of each group of protrusions 41 is set on a straight line to shorten the current transmission path of the transmission electrode 40, improve the current transmission efficiency, and ensure the photoelectric conversion efficiency of the solar cell.

[0096] Optionally, such as Figures 1 to 4 As shown, the recessed portion 43 in the embodiments of this application includes a plurality of recessed portions 43 arranged in an array.

[0097] like Figures 1 to 4 As shown, the multiple recesses 43 in the embodiments of this application have the same or similar structures, and the multiple recesses 43 are arranged in an array. This reduces the amount of material used in the transmission electrode 40, reduces the manufacturing cost of the transmission electrode 40, thereby reducing the cost of the solar cell and enhancing its market competitiveness.

[0098] It should be noted that in the embodiments of this application, the structures of the multiple recesses 43 can be completely identical. For example, the projections of the multiple recesses 43 onto the plane where the base 10 is located are all circular. The structures of the multiple recesses 43 can also be partially identical. For example, a portion of the multiple recesses 43 may have a circular projection onto the plane where the base 10 is located, while another portion may be rectangular.

[0099] Optionally, such as Figure 5 As shown, the recessed portion 43 in this embodiment includes a first recessed portion 431 and a second recessed portion 432, and the area of ​​the second recessed portion 432 is many times the area of ​​the first recessed portion 431.

[0100] like Figure 5 As shown, the recessed portion 43 in this embodiment includes a first recessed portion 431 and a second recessed portion 432, and the second recessed portion 432 includes a plurality of first recessed portions 431. That is, the plurality of first recessed portions 431 are directly connected to form the second recessed portion 432, and no protrusion 41 is provided in the middle. Therefore, the area of ​​the second recessed portion 432 is many times the area of ​​the first recessed portion 431.

[0101] For example, the second recess 432 is formed by connecting four first recesses 431, and there is no protrusion 41 in the middle. Therefore, the area of ​​the second recess 432 is greater than four times the area of ​​the first recess 431.

[0102] In this embodiment, by setting the area of ​​the second recess 432 to be multiple times the area of ​​the first recess 431, the amount of material used in the transmission electrode 40 is further reduced, the manufacturing cost of the transmission electrode 40 is reduced, thereby reducing the cost of the solar cell and enhancing its market competitiveness.

[0103] Optionally, such as Figure 6 As shown, the protrusion 41 in this embodiment includes a first protrusion 411 and a second protrusion 412, and the area of ​​the second protrusion 412 is many times the area of ​​the first protrusion 411.

[0104] like Figure 6 As shown, the protrusion 41 in this embodiment includes a first protrusion 411 and a second protrusion 412, and the second protrusion 412 includes a plurality of first protrusions 411. That is, the plurality of first protrusions 411 are directly connected to form the second protrusion 412, and there is no recess 43 in the middle. Therefore, the area of ​​the second protrusion 412 is many times the area of ​​the first protrusion 411.

[0105] For example, the second protrusion 412 is formed by connecting three first protrusions 411, and there is no recess 43 in the middle. Therefore, the area of ​​the second protrusion 412 is greater than three times the area of ​​the first protrusions 411.

[0106] In this embodiment of the application, the area of ​​the second protrusion 412 is set to be multiple times the area of ​​the first protrusion 411 to enhance the current transmission capability of the transmission electrode 40 and ensure the photoelectric conversion efficiency of the solar cell.

[0107] In a preferred embodiment of this application, the angle between the extending direction of the second protrusion 412 and the extending direction of the transmission electrode 40 is set to be less than or equal to 30 degrees. Since the current transmission direction in the transmission electrode 40 is typically the same as the extending direction of the transmission electrode 40, setting the angle between the extending direction of the second protrusion 412 and the extending direction of the transmission electrode 40 to be less than or equal to 30 degrees can further enhance the current transmission capability of the transmission electrode 40 and improve the photoelectric conversion efficiency of the solar cell.

[0108] Optionally, in this embodiment of the application, the distance between the center points of two adjacent recesses 43 is greater than or equal to 20 μm and less than or equal to 100 μm.

[0109] like Figures 1 to 3 As shown, taking the projection of the recessed portion 43 onto the plane of the base 10 as a circle as an example, the distance between two adjacent center circles is greater than or equal to 20 μm and less than or equal to 100 μm. Figures 4 to 6As shown, taking the projection of the recessed portion 43 onto the plane of the base 10 as a near-square structure as an example, the distance between the center points of two adjacent squares is greater than or equal to 20μm and less than or equal to 100μm. Here, the near-square is a quadrilateral with four arc-shaped sides and two oppositely arranged sides that are symmetrical.

[0110] In this embodiment, the distance between the center points of two adjacent recesses 43 is set to be greater than or equal to 20 μm and less than or equal to 100 μm to reduce the amount of material used in the transmission electrode 40 and reduce the manufacturing cost of the transmission electrode 40. Simultaneously, it also avoids the situation where a large distance between two adjacent protrusions 41 affects the current transmission efficiency of the transmission electrode 40.

[0111] For example, the distance between the center points of two adjacent recesses 43 can be set to 20μm, 30μm, 40μm, 50μm, 60μm, 70μm, 80μm, 90μm, 100μm, etc.

[0112] Optionally, along the thickness direction of the solar cell, the recess 43 has a first depth relative to the top of the protrusion 41, and the ratio of the first depth to the distance between the center points of two adjacent recesses 43 is greater than or equal to 0.1 and less than or equal to 1.

[0113] In this embodiment, along the thickness direction of the solar cell, the recessed portion 43 has a first depth relative to the top of the protrusion 41, and this first depth is equal to the height of the top of the protrusion 41 relative to the recessed portion 43. The ratio of the first depth to the distance between the center points of two adjacent recessed portions 43 is set to be greater than or equal to 0.1 and less than or equal to 1, so that the size of the recessed portion 43 is more optimized, thereby further reducing the amount of material used in the transmission electrode 40, reducing the manufacturing cost of the transmission electrode 40, and at the same time ensuring the current transmission efficiency of the transmission electrode 40, thus ensuring the photoelectric conversion efficiency of the photovoltaic module.

[0114] For example, in the embodiments of this application, the ratio of the first depth of the recess 43 relative to the top of the protrusion 41 to the distance between the center points of two adjacent recesses 43 can be set to 0.1, 0.3, 0.5, 0.7, 0.8, 1.0, etc.

[0115] Optionally, along the thickness direction of the solar cell, the sum of the thickness of the transmission electrode 40 corresponding to the protrusion 41 and the thickness of the protrusion 41 is greater than or equal to 9 μm and less than or equal to 50 μm; and / or, along the thickness direction of the solar cell, the thickness of the transmission electrode 40 corresponding to the recess 43 is greater than or equal to 1 μm and less than or equal to 20 μm.

[0116] In this embodiment of the application, along the thickness direction of the solar cell, the sum of the thickness of the transmission electrode 40 corresponding to the protrusion 41 and the thickness of the protrusion 41 is set to be greater than or equal to 9 μm and less than or equal to 50 μm. That is, the sum of the thickness of the protrusion 41 and the thickness of the transmission electrode 40 is greater than or equal to 9 μm and less than or equal to 50 μm.

[0117] By implementing the above configuration, not only can the amount of material used in the transmission electrode 40 be reduced, thus lowering its manufacturing cost and helping to reduce the cost of solar cells and enhance their market competitiveness, but the transmission electrode 40 can also achieve higher transmission efficiency, ensuring the photoelectric conversion efficiency of the solar cell.

[0118] For example, along the thickness direction of the solar cell, the sum of the thickness of the transmission electrode 40 corresponding to the protrusion 41 and the thickness of the protrusion 41 can be set to 9μm, 10μm, 20μm, 30μm, 40μm, 50μm, etc.

[0119] In this embodiment of the application, along the thickness direction of the solar cell, the thickness of the transmission electrode 40 corresponding to the recess 43 is set to be greater than or equal to 1 μm and less than or equal to 20 μm.

[0120] In this embodiment, along the thickness direction of the solar cell, the thickness of the transmission electrode 40 corresponding to the recess 43 is set to be greater than or equal to 1 μm and less than or equal to 20 μm, thereby reducing the amount of material used in the transmission electrode 40 and reducing the manufacturing cost of the transmission electrode 40. Furthermore, the transmission electrode 40 corresponding to the recess 43 can be connected to an adjacent protrusion 41, thereby improving the current transmission efficiency of the transmission electrode 40 and enhancing the photoelectric conversion efficiency of the solar cell.

[0121] Optionally, such as Figures 1 to 6 As shown, in the embodiments of this application, the projection of the recessed portion 43 onto the plane of the base 10 is at least one of a circular structure, an elliptical structure, a square structure, and a square-like structure.

[0122] like Figures 1 to 6 As shown, the recessed portion 43 in this embodiment of the application has a projection on the plane where the base 10 is located. The projection can be a circular structure, an elliptical structure, a square structure, such as a square structure, a rectangular structure, or a square-like structure. The square-like structure refers to a square structure with each side being arc-shaped.

[0123] In this embodiment, the projection of the recessed portion 43 onto the plane of the substrate 10 is set to at least one of a circular structure, an elliptical structure, a square structure, or a near-square structure. This helps to reduce the amount of material used in the transmission electrode 40, reduce the manufacturing cost of the transmission electrode 40, thereby reducing the cost of the solar cell and enhancing its market competitiveness.

[0124] Optionally, the transmission electrode 40 in this embodiment includes a plurality of electrodes, each of which extends along a third direction C and is arranged at intervals along a fourth direction D; wherein the fourth direction D intersects with the third direction C.

[0125] The transmission electrode 40 in this embodiment includes multiple electrodes, each extending along a third direction and arranged at intervals along the fourth direction D, so as to collect the current generated by the substrate 10 through the multiple transmission electrodes 40, improve the current transmission efficiency, and ensure the photoelectric conversion efficiency of the solar cell.

[0126] For example, when the solar cell is a back-contact solar cell, a plurality of transmission electrodes 40 are disposed on the back side of the substrate 10, and the plurality of transmission electrodes 40 include a positive transmission electrode and a negative transmission electrode. The positive transmission electrode and the negative transmission electrode may be alternately arranged on the back side of the substrate 10.

[0127] When the solar cell is a bifacial cell, a portion of the multiple transmission electrodes 40 are disposed on the front side of the substrate 10 and another portion are disposed on the back side of the substrate 10. The polarities of the transmission electrodes 40 disposed on the front side of the substrate 10 and the transmission electrodes 40 disposed on the back side of the substrate 10 are different.

[0128] Optionally, such as Figure 7 and Figure 8 As shown, the solar cell disclosed in this application embodiment also includes a passivation layer 20, which is stacked between the substrate 10 and the transmission electrode 40; and a contact electrode 30, which is disposed through the passivation layer 20, with one end of the contact electrode 30 electrically connected to the substrate 10 and the other end of the contact electrode 30 electrically connected to the transmission electrode 40.

[0129] like Figure 7 and Figure 8 As shown in the embodiment of this application, a passivation layer 20 is stacked between the substrate 10 and the transmission electrode 40. The passivation layer 20 has insulating properties and protects the substrate 10 to avoid problems such as short circuits in the solar cell.

[0130] It should be noted that the passivation layer 20 in the embodiments of this application includes, but is not limited to, at least one of silicon nitride layer, silicon oxide layer, silicon oxynitride layer, aluminum oxide layer, silicon carbide layer, and amorphous silicon layer.

[0131] In this embodiment, a contact electrode 30 is disposed through the passivation layer 20, with one end of the contact electrode 30 abutting against the substrate 10 and electrically connected to the substrate 10, and the other end of the contact electrode 30 abutting against the transmission electrode 40 and electrically connected to the transmission electrode 40. The contact electrode 30 connects the substrate 10 and the transmission electrode 40, thereby conducting the current generated by the substrate 10 to the transmission electrode 40, and then transmitting the current to the external circuit through the transmission electrode 40.

[0132] It should be noted that the contact electrode 30 in this embodiment can be made of metals such as silver, copper, aluminum, nickel, gold, zinc, tin, and lead. The contact electrode 30 can also be made of metal oxides, metal nitrides, metal carbides, or metal sulfides. For example, the metal oxide can be indium tin oxide, and the metal nitride can be tin nitride, etc. In this embodiment, no excessive restrictions are placed on the specific material of the contact electrode 30; in practical applications, those skilled in the art can choose according to their needs.

[0133] In this embodiment, a point contact technique is used to connect the substrate 10 and the transmission electrode 40. On one hand, this effectively reduces the direct connection area between the transmission electrode 40 and the substrate 10, thereby improving the passivation capability of the substrate 10 surface. On the other hand, the contact electrode 30 can be selected from structures and materials with a low recombination rate after contacting the substrate 10, thus reducing the recombination rate at the contact interface between the contact electrode 30 and the substrate 10. Furthermore, the contact electrode 30 can be made from materials with better contact performance; for example, materials with lower resistance can be used to reduce resistance and improve transmission performance. Finally, since the material cost of the contact electrode 30 is relatively high, the above-mentioned design can reduce the amount of material used in the contact electrode 30, thereby significantly reducing the production cost of the solar cell.

[0134] Optionally, such as Figure 8 As shown, in this embodiment of the application, the transmission electrode 40 has a first projection on the plane where the substrate 10 is located, and the contact electrode 30 has a second projection on the plane where the substrate 10 is located, with the second projection falling into the first projection.

[0135] like Figure 8 As shown, in this embodiment, the transmission electrode 40 has a first projection on the plane of the substrate 10, and the contact electrode 30 has a second projection on the plane of the substrate 10, with the second projection falling within the first projection. It can be understood that along the fourth direction D, the width of the transmission electrode 40 is greater than or equal to the width of the contact electrode 30. This allows the contact electrode 30 to connect the substrate 10 and the transmission electrode 40, thereby ensuring the current transmission efficiency of the transmission electrode 40 and guaranteeing the photoelectric conversion efficiency of the solar cell.

[0136] Optionally, such as Figure 8As shown in the embodiments of this application, the width of the transmission electrode 40 along the fourth direction D is greater than or equal to 60 μm; and / or, the width of the contact electrode 30 along the fourth direction D is greater than or equal to 10 μm and less than or equal to 40 μm.

[0137] like Figure 8 As shown in this embodiment, along the fourth direction D, the width of the transmission electrode 40 is set to be greater than or equal to 60 μm, and the width of the contact electrode 30 is set to be greater than or equal to 10 μm and less than or equal to 40 μm. Even if the transmission electrode 40 is significantly offset from the contact electrode 30 along the fourth direction D, the transmission electrode 40 can still be electrically connected to the contact electrode 30, giving the transmission electrode 40 good current transmission capability, thereby ensuring the current transmission efficiency of the transmission electrode 40 and the photoelectric conversion efficiency of the solar cell. Although the width of the transmission electrode 40 is relatively wide, because there are multiple arrayed protrusions 41 on the side of the transmission electrode 40 away from the substrate 10, the amount of paste used in the transmission electrode 40 can be reduced without affecting the transmission efficiency of the transmission electrode 40, thus reducing the cost of the paste and helping to reduce the manufacturing cost of the solar cell and enhance its market competitiveness.

[0138] For example, along the fourth direction D, the width of the transmission electrode 40 can be set to 60μm, 65μm, 70μm, 75μm, 80μm, 85μm, 90μm, etc. Along the fourth direction D, the width of the contact electrode 30 can be set to 10μm, 15μm, 20μm, 25μm, 30μm, 35μm, 40μm, etc.

[0139] Optionally, such as Figure 7 As shown, in this embodiment of the application, the substrate 10 has a first surface and a second surface disposed opposite to each other, the passivation layer 20 is stacked on the first surface of the substrate 10, and / or the passivation layer 20 is stacked on the second surface of the substrate 10.

[0140] like Figure 7 As shown, the substrate 10 in this embodiment has a first surface and a second surface disposed opposite to each other, with the first surface of the substrate 10 as the front and the second surface as the back. The passivation layer 20 may be stacked only on the first surface of the substrate 10, meaning the transmission electrode 40 is also disposed only on the first surface of the substrate 10. Alternatively, the passivation layer 20 may be stacked only on the second surface of the substrate 10, meaning the transmission electrode 40 is also disposed only on the first surface of the substrate 10, and the solar cell is a back-contact solar cell. Or, the passivation layer 20 may be stacked on both the first and second surfaces of the substrate 10, meaning the transmission electrode 40 is disposed on both the first and second surfaces of the substrate 10, and the solar cell is a bifacial solar cell.

[0141] Optionally, along the second direction B, the distance between the center points of two adjacent protrusions 41 is W1; along the fourth direction D, the width of the contact electrode 30 is W2, satisfying -2 < lg(W2 / W1) < 2; wherein, the second direction B intersects the third direction C, and the fourth direction D is perpendicular to the third direction C.

[0142] In this embodiment, along the second direction B, the distance between the center points of two adjacent protrusions 41 is set to W1, and along the fourth direction D, the width of the contact electrode 30 is set to W2, satisfying -2 < lg(W2 / W1) < 2. This setting reduces the transmission resistance between the contact electrode 30 and the transmission electrode 40, ensuring current transmission efficiency and improving the photoelectric conversion efficiency of the solar cell.

[0143] For example, lg(W2 / W1) can be set to -2, -1.5, -1, 0, 0.5, 1, 2, etc.

[0144] In a preferred embodiment of this application, -1 < lg(W2 / W1) < 1 is satisfied. This further reduces the transmission resistance between the contact electrode 30 and the transmission electrode 40, ensuring current transmission efficiency and improving the photoelectric conversion efficiency of the solar cell.

[0145] For example, lg(W2 / W1) can be set to -1, -0.8, -0.5, -0.2, 0, 0.2, 0.5, 0.7, 1, etc.

[0146] Optionally, W2 ≥ 30 μm must be satisfied.

[0147] In this embodiment, along the fourth direction D, the width W2 of the contact electrode 40 can be set to be greater than or equal to 30 μm to ensure that the contact electrode 30 can make good contact with the transmission electrode 40, and the current can be better transmitted from the contact electrode 30 to the transmission electrode 40, thus ensuring the photoelectric conversion efficiency of the solar cell.

[0148] For example, along the fourth direction D, the width W2 of the contact electrode 40 can be set to 30μm, 32μm, 35μm, 38μm, 40μm, etc.

[0149] Optionally, W1 < 2W2 must be satisfied.

[0150] In this embodiment, the distance W1 between the center points of two adjacent protrusions 41 is set to be less than twice the width W2 of the contact electrode 30, so as to ensure that the contact electrode 30 is at least partially located below the protrusion 41, that is, the contact electrode 30 and the protrusion 41 of the transmission electrode 40 are in contact. The protrusion 41 is thicker and has a smaller transmission resistance, thereby reducing the resistance during current transmission and increasing the current transmission efficiency, which helps to improve the photoelectric conversion efficiency of the solar cell.

[0151] Optionally, the distance between the center points of two adjacent recesses 43 is W3, and the width of the contact electrode 30 along the fourth direction D is W2, satisfying W2-W3>10μm.

[0152] In this embodiment, the difference between the width W2 of the contact electrode 30 and the distance W3 between the center points of two adjacent recesses 43 is set to be greater than 10 μm, so that the contact electrode 30 is located below more protrusions 41, and the contact electrode 30 and more protrusions 41 of the transmission electrode 40 are in contact. The protrusions 41 are thicker and have lower transmission resistance, thereby reducing the resistance during current transmission and increasing the current transmission efficiency, which helps to improve the photoelectric conversion efficiency of the solar cell.

[0153] For example, the difference between the width W2 of the contact electrode 30 and the distance W3 between the center points of two adjacent recesses 43 can be set to 11μm, 12μm, 13μm, 14μm, 15μm, etc.

[0154] One alternative implementation, such as Figure 8 As shown, the contact electrode 30 in this embodiment is a long strip structure. The contact electrode 30 extends along a third direction C, which is the same as the extension direction of the transmission electrode 40.

[0155] Another alternative implementation, such as Figure 8 As shown, the projection of the contact electrode 30 on the plane of the substrate 10 in this embodiment can be circular, square, elliptical, or square-like.

[0156] The contact electrode 30 may include a group of multiple contact electrodes 30, which are spaced apart along a third direction C; the third direction C is the same as the extending direction of the transmission electrode 40. Alternatively, the contact electrode 30 may include multiple groups of contact electrodes 30, which are spaced apart along a fourth direction D; wherein the fourth direction D intersects with the third direction C.

[0157] Of course, such as Figure 8 As shown, the contact electrode 30 can also include the two types mentioned above, and the contact electrodes 30 of the two types are arranged at intervals along the third direction C.

[0158] The above are just a few examples of specific structures for the contact electrode 30 and are not intended to limit this application. In practical applications, those skilled in the art can customize the specific structure of the contact electrode 30 as needed.

[0159] Optionally, in this embodiment, the substrate 10 includes a first surface and a second surface disposed opposite to each other. The second surface has a first electrode region and a second electrode region disposed adjacent to each other, and the polarities of the first electrode region and the second electrode region are opposite. The transmission electrode 40 includes a first transmission electrode and a second transmission electrode. The first transmission electrode is disposed in the first electrode region and is electrically connected to the first electrode region. The second transmission electrode is disposed in the second electrode region and is electrically connected to the second electrode region. In this embodiment, along the thickness direction of the solar cell, the height of the protrusion 41 in the first transmission electrode and the height of the protrusion 41 in the second transmission electrode are the same or different.

[0160] When the solar cell is a back-contact solar cell, the first surface of the substrate 10 is the sunlight-receiving surface, also known as the front side. The second surface of the substrate 10 is the back-contact surface, also known as the back side. The second surface has adjacent first and second electrode regions, each comprising multiple regions. Both the multiple first and second electrode regions extend along a third direction C and are alternately arranged along a fourth direction D. For example, the first electrode region is a P region and the second electrode region is an N region, or vice versa.

[0161] The contact electrode includes a first contact electrode and a second contact electrode. The first contact electrode passes through the passivation layer, and one end of the first contact electrode is connected to a first electrode region. A first transmission electrode is disposed on the first contact electrode and electrically connected to the other end of the first contact electrode. The second contact electrode passes through the passivation layer, and one end of the second contact electrode is connected to a second electrode region. A second transmission electrode is disposed on the second contact electrode and electrically connected to the other end of the second contact electrode.

[0162] It should be noted that in this embodiment, both the first and second transmission electrodes have multiple protrusions 41 on the side away from the substrate 10, and these protrusions 41 are arranged in an array. The height of the protrusions 41 included in the first transmission electrode and the height of the protrusions 41 included in the second transmission electrode can be the same or different. This embodiment does not impose specific limitations on this; in practical applications, those skilled in the art can adjust the heights according to the needs of current collection. This allows for more suitable heights of the protrusions 41 included in the first and second transmission electrodes, further controlling the amount of material used in the transmission electrode 40, reducing the production cost of the solar cell, and enhancing the market competitiveness of the solar cell.

[0163] Optionally, the distance between the center points of two adjacent recesses 43 in the first transmission electrode is different from the distance between the center points of two adjacent recesses 43 in the second transmission electrode.

[0164] In this embodiment, the distance between the center points of two adjacent recesses 43 in the first transmission electrode is different from the distance between the center points of two adjacent recesses 43 in the second transmission electrode. For example, the distance between the center points of two adjacent recesses 43 in the first transmission electrode is greater than the distance between the center points of two adjacent recesses 43 in the second transmission electrode. Alternatively, the distance between the center points of two adjacent recesses 43 in the first transmission electrode is less than the distance between the center points of two adjacent recesses 43 in the second transmission electrode.

[0165] In this embodiment, by setting the distance between the center points of two adjacent recesses 43 in the first transmission electrode to be different from the distance between the center points of two adjacent recesses 43 in the second transmission electrode, the distance between the center points of two adjacent recesses 43 in the first transmission electrode and the distance between the center points of two adjacent recesses 43 in the second transmission electrode are made more suitable, thereby further controlling the amount of material used in the transmission electrode 40, reducing the production cost of the solar cell, and enhancing the market competitiveness of the solar cell.

[0166] This application also discloses a photovoltaic module, which includes the solar cells described in the above embodiments.

[0167] It should be noted that in this embodiment, the photovoltaic module includes solar cells with the same structure as those described in the above embodiments, and their beneficial effects are similar. Further details will not be repeated here.

[0168] It should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0169] Although alternative embodiments of the present invention have been described, those skilled in the art, upon learning the basic inventive concept, can make further changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the alternative embodiments as well as all changes and modifications falling within the scope of the embodiments of the present invention.

[0170] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used merely to distinguish one entity from another, and do not necessarily require or imply any such actual relationship or order between these entities. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that an article or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an article or terminal device. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the article or terminal device that includes that element.

[0171] The technical solution provided by the present invention has been described in detail above. Specific examples have been used to illustrate the principle and implementation of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation and application scope based on the principle and implementation of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A solar cell, characterized in that, include: Base; A transmission electrode is disposed on the surface of the substrate and electrically connected to the substrate. A plurality of protrusions are sequentially disposed on the side of the transmission electrode away from the substrate. The plurality of protrusions are arranged in an array, and adjacent protrusions are at least partially connected. The protrusions include multiple sets, and the multiple sets of protrusions are arranged sequentially along the first direction; Each group of protrusions includes multiple protrusions, and the multiple protrusions are arranged sequentially along the second direction; Wherein, the extension direction of the transmission electrode is a third direction, the second direction intersects the third direction, and the first direction intersects the second direction and the third direction; The first direction and the second direction have a second included angle, which is less than or equal to 90 degrees; the second direction and the third direction have a first included angle. The adjacent protrusions enclose a first region, and the transmission electrode corresponding to the first region is a recess. Along the thickness direction of the solar cell, the height of the protrusion is greater than or equal to 5 μm and less than or equal to 30 μm; the height of the protrusion is the distance between the top of the protrusion and the recess.

2. The solar cell according to claim 1, characterized in that, The first included angle is greater than or equal to 0 degrees and less than or equal to 60 degrees.

3. The solar cell according to claim 1, characterized in that, The first included angle is greater than or equal to 0 degrees and less than or equal to 45 degrees.

4. The solar cell according to claim 1, characterized in that, Along the thickness direction of the solar cell, the height of the protrusion is greater than or equal to 5 μm and less than or equal to 15 μm.

5. The solar cell according to claim 1, characterized in that, The projection of the protrusion onto the plane of the base is at least one of a cross-shaped structure, a hexagonal structure, or a triangular structure.

6. The solar cell according to claim 1, characterized in that, The line connecting the center points of each group of protrusions lies on a straight line.

7. The solar cell according to claim 1, characterized in that, The recessed portion includes multiple recessed portions, which are arranged in an array.

8. The solar cell according to claim 7, characterized in that, The recessed portion includes a first recessed portion and a second recessed portion, wherein the area of ​​the second recessed portion is multiple times the area of ​​the first recessed portion. And / or, the protrusion includes a first protrusion and a second protrusion, wherein the area of ​​the second protrusion is multiple times the area of ​​the first protrusion.

9. The solar cell according to claim 7, characterized in that, The distance between the center points of two adjacent recesses is greater than or equal to 20 μm and less than or equal to 100 μm.

10. The solar cell according to claim 7, characterized in that, Along the thickness direction of the solar cell, the recess has a first depth relative to the top of the protrusion, and the ratio of the first depth to the distance between the center points of two adjacent recesses is greater than or equal to 0.1 and less than or equal to 1.

11. The solar cell according to claim 7, characterized in that, Along the thickness direction of the solar cell, the sum of the thickness of the transmission electrode corresponding to the protrusion and the thickness of the protrusion is greater than or equal to 9 μm and less than or equal to 50 μm. And / or, along the thickness direction of the solar cell, the thickness of the transmission electrode corresponding to the recess is greater than or equal to 1 μm and less than or equal to 20 μm.

12. The solar cell according to claim 7, characterized in that, The projection of the recessed portion onto the plane of the substrate is at least one of a circular structure, an elliptical structure, a square structure, or a near-square structure.

13. The solar cell according to claim 7, characterized in that, The transmission electrodes include a plurality of electrodes, each extending along a third direction and spaced apart along a fourth direction. The fourth direction intersects with the third direction.

14. The solar cell according to claim 13, characterized in that, The solar cell also includes: A passivation layer is stacked between the substrate and the transmission electrode; A contact electrode is disposed through the passivation layer, with one end of the contact electrode electrically connected to the substrate and the other end of the contact electrode electrically connected to the transmission electrode.

15. The solar cell according to claim 14, characterized in that, The transmission electrode has a first projection on the plane of the substrate, and the contact electrode has a second projection on the plane of the substrate, the second projection falling within the first projection.

16. The solar cell according to claim 15, characterized in that, Along the fourth direction, the width of the transmission electrode is greater than or equal to 60 μm; And / or, along the fourth direction, the width of the contact electrode is greater than or equal to 10 μm and less than or equal to 40 μm.

17. The solar cell according to claim 14, characterized in that, The substrate has a first surface and a second surface disposed opposite to each other, the passivation layer is stacked on the first surface of the substrate, and / or the passivation layer is stacked on the second surface of the substrate.

18. The solar cell according to claim 14, characterized in that, Along the second direction, the distance between the center points of two adjacent protrusions is W1; Along the fourth direction, the width of the contact electrode is W2, which satisfies -2 < lg(W2 / W1) < 2; Wherein, the second direction intersects with the third direction, and the fourth direction is perpendicular to the third direction.

19. The solar cell according to claim 18, characterized in that, The condition is satisfied that -1 < lg(W2 / W1) < 1.

20. The solar cell according to claim 18, characterized in that, The W2 ≥ 30 μm requirement is met.

21. The solar cell according to claim 18, characterized in that, The condition is satisfied that W1 < 2W2.

22. The solar cell according to claim 18, characterized in that, The distance between the center points of two adjacent recesses is W3, and the width of the contact electrode along the fourth direction is W2, satisfying W2-W3>10μm.

23. The solar cell according to claim 1, characterized in that, The substrate includes a first surface and a second surface disposed opposite to each other, the second surface having a first electrode region and a second electrode region disposed adjacent to each other, the first electrode region and the second electrode region having opposite polarities; The transmission electrode includes a first transmission electrode and a second transmission electrode. The first transmission electrode is disposed in the first electrode region and electrically connected to the first electrode region, and the second transmission electrode is disposed in the second electrode region and electrically connected to the second electrode region. Wherein, along the thickness direction of the solar cell, the height of the protrusion in the first transmission electrode is the same as or different from the height of the protrusion in the second transmission electrode.

24. The solar cell according to claim 23, characterized in that, The distance between the center points of two adjacent recesses in the first transmission electrode is different from the distance between the center points of two adjacent recesses in the second transmission electrode.

25. A photovoltaic module, characterized in that, The photovoltaic module includes the solar cell according to any one of claims 1-24.

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