Solar cell, cell assembly and photovoltaic system

Abstract

This disclosure can be applied to the field of photovoltaic technology and provides a solar cell, a cell assembly, and a photovoltaic system. The solar cell comprises the following: a silicon substrate containing a first region, wherein the first region is provided with a plurality of first tower base structures and a plurality of second tower base structures, with at least some of the second tower base structures being arranged on top of the first tower base structures. The composite arrangement of the first tower base structures and the second tower base structures increases the complexity of the surface morphology of the first region and can significantly enhance the photoelectric conversion efficiency and the mechanical strength of the solar cell.

Description

Cross-reference to related registration

[0001] This disclosure claims priority over Chinese patent application No. 202410950720.8, filed with the Chinese Patent Office on July 15, 2024, entitled “SOLAR CELL, CELL ASSEMBLY AND PHOTOVOLTAIC SYSTEM”, which is hereby incorporated in full by reference. Technical field

[0002] This disclosure pertains to the field of photovoltaic technology and specifically concerns a solar cell, a cell assembly and a photovoltaic system. State of the art

[0003] The efficiency of the photoelectric conversion and the mechanical strength of solar cells are two crucial performance indicators. On the one hand, the characteristic dimensions of existing textured surface structures, which are either too large or too small, have a certain negative impact on the subsequent film passivation and the contact areas of the paste, which in turn impairs cell performance.

[0004] On the other hand, conventional silicon wafers tend to develop stress concentrations during manufacturing and use, and particularly during the growth of polycrystalline silicon films at high temperatures, this stress concentration leads to wafer warping. During the automated manufacturing and delivery process, silicon wafers are susceptible to mechanical damage such as hidden cracks, chips, scratches, and edge breakage due to stress, which impairs product yield and reliability. Brief description

[0005] This disclosure provides a solar cell, a cell assembly and a photovoltaic system and aims to solve the problems that, in the prior art, there are significant deficiencies regarding mechanical performance, the efficiency of the photoelectric conversion is low and the product reliability is inadequate.

[0006] This revelation is implemented in the following way: A solar cell contains: a silicon substrate that includes a first region, wherein the first region is provided with a plurality of first tower base structures and a plurality of second tower base structures, wherein at least some of the second tower base structures are arranged on the first tower base structures.

[0007] In some embodiments, the longest diagonal length of the first tower base structures is greater than or equal to 2 µm and less than or equal to 60 µm.

[0008] In some embodiments, the longest diagonal length of the first tower base structures is greater than or equal to 5 µm and less than or equal to 40 µm.

[0009] In some embodiments, the longest diagonal length of the first tower base structures is greater than or equal to 10 µm and less than or equal to 30 µm.

[0010] In some embodiments, the longest diagonal length of the first tower base structures is greater than or equal to 15 µm and less than or equal to 30 µm.

[0011] In some embodiments, the longest diagonal length of the second tower base structures is greater than or equal to 0.5 µm and less than or equal to 30 µm.

[0012] In some embodiments, the longest diagonal length of the second tower base structures is greater than or equal to 1 µm and less than or equal to 30 µm.

[0013] In some embodiments, the longest diagonal length of the second tower base structures is greater than or equal to 1 µm and less than or equal to 20 µm.

[0014] In some embodiments, the longest diagonal length of the second tower base structures is greater than or equal to 5 µm and less than or equal to 20 µm.

[0015] In some embodiments, the ratio of the total area of ​​orthographic projections of the second tower base structures on the first region to the area of ​​the first region is greater than 60%.

[0016] In some embodiments, a second region is also included, and the second region and the first region are located on the same side of the silicon substrate or on two opposite sides of the silicon substrate.

[0017] In some embodiments, the second region is provided with a multitude of third tower base structures.

[0018] In some embodiments, the longest diagonal length of the third tower base structures is greater than or equal to 2 µm and less than or equal to 60 µm.

[0019] In some embodiments, the longest diagonal length of the third tower base structures is greater than or equal to 5 µm and less than or equal to 40 µm.

[0020] In some embodiments, the longest diagonal length of the third tower base structures is greater than or equal to 10 µm and less than or equal to 30 µm.

[0021] In some embodiments, the longest diagonal length of the third tower base structures is greater than or equal to 15 µm and less than or equal to 30 µm.

[0022] In some embodiments, the longest diagonal length of the first tower base structures is greater than the longest diagonal length of the second tower base structures.

[0023] In some embodiments, the ratio of the longest diagonal length of the first tower base structures to the longest diagonal length of the third tower base structures is in the range of 0.5 to 2.

[0024] In some embodiments, the roughness of the first region is greater than the roughness of the second region.

[0025] In some embodiments, the multitude of first tower base structures are arranged in a linear series.

[0026] In some embodiments, the multitude of third tower base structures are arranged in a linear series.

[0027] In some embodiments, the first tower base structures are downward-curved structures, or the second tower base structures are downward-curved structures, or the first tower base structures and the second tower base structures are downward-curved structures.

[0028] In some embodiments, the depth of a downward bulge of the first tower base structures is greater than or equal to 0.05 µm and less than or equal to 2 µm, or the depth of a downward bulge of the second tower base structures is greater than or equal to 0.05 µm and less than or equal to 2 µm, or the depth of a downward bulge of the first tower base structures and the depth of a downward bulge of the second tower base structures are greater than or equal to 0.05 µm and less than or equal to 2 µm.

[0029] In some embodiments, the third tower base structures are downward-curving structures.

[0030] In some embodiments, the depth of a downward curvature of the third tower base structures is greater than or equal to 0.05 µm and less than or equal to 1.5 µm.

[0031] This disclosure further provides a cell assembly comprising the above solar cell.

[0032] This disclosure further provides a photovoltaic system comprising the above cell assembly.

[0033] This disclosure has the advantageous effects that the composite arrangement of the first tower base structures and the second tower base structures increases the complexity of the surface morphology of the first region and can enhance the photoelectric response and mechanical strength of the solar cell. Brief description of the drawings Fig. Figure 1 shows a scanning electron microscope image of a first region of a solar cell according to this disclosure at a magnification of 1000x; Fig. Figure 2 shows a scanning electron microscope image of first tower base structures of the solar cell according to this disclosure at a first angle; Fig. Figure 3 shows a scanning electron microscope image of the first tower base structures of the solar cell according to this disclosure at a second angle; Fig. Figure 4 shows a scanning electron microscope image of the first tower base structures of the solar cell according to this disclosure at a third angle; Fig. Figure 5 shows a scanning electron microscope image of a second region of a solar cell according to this disclosure at a magnification of 1000x; Fig. Figure 6 shows a scanning electron microscope image of the third tower base structures of the solar cell according to this disclosure at a first angle, and Fig. Figure 7 shows a scanning electron microscope image of the third tower base structures of the solar cell according to this disclosure at a third angle. Descriptions of the reference symbols:

[0034] 101 - first tower base structure; 102 - second tower base structure and 103 - third tower base structure. Detailed description of the embodiments

[0035] To make the objectives, technical solutions, and advantages of this disclosure clearly understandable, it is described in detail below in conjunction with the accompanying drawings and the embodiments specified below. Examples of the embodiments are shown in the accompanying drawings, and the same or similar elements, or elements having the same or similar functions, are identified throughout the description by the same or similar reference numerals. The embodiments described below with reference to the accompanying drawings are exemplary, are used only to illustrate this disclosure, and must not be interpreted as limiting it. Furthermore, it is understood that the specific embodiments described here serve only to illustrate this disclosure and do not limit it.

[0036] In describing this disclosure, it should be noted that orientation or position relationships indicated by terms such as "length," "width," "top," "bottom," "left," "right," "horizontal," "top," and "bottom" are based on orientation and position relationships illustrated in the accompanying drawings and serve only to facilitate and simplify the description of this disclosure. They do not indicate or imply that a device or element referred to must have a particular orientation or be manufactured or operated in a particular orientation. Such terms should therefore not be understood as limiting this disclosure.

[0037] Furthermore, the terms “first” and “second” are used for descriptive purposes only and should not be interpreted as indicating or implying relative importance or a set of specified technical features. Features defined as “first” and “second” may therefore explicitly or implicitly include one or more of the features. Unless expressly stated otherwise, “a multitude of” in the descriptions of this disclosure means two or more than two.

[0038] In the description of this disclosure, it should be noted that the terms "assembled," "connected," and "linked" are to be understood in a broad sense, unless otherwise expressly stated or defined. For example, they may refer to a fixed connection, a detachable connection, or an integrated connection; they may refer to a mechanical connection, an electrical connection, or a reciprocal connection; or they may refer to a direct connection, an indirect connection through an intermediary, communication between the interiors of two elements, or an interactional relationship between the two elements. Individuals skilled in the art may understand the specific meanings of the above terms in this disclosure according to specific situations.

[0039] Unless otherwise expressly stated or limited, in this disclosure a first feature that is “above” or “below” a second feature may imply direct contact between the first feature and the second feature, or it may imply indirect contact between the first feature and the second feature through an additional feature intervening. Furthermore, a first feature that is “above,” “over,” or “on top” of the second feature implies that the first feature is above and above the second feature, or simply indicates that one level of the first feature is higher than that of the second feature.The first feature, which is “below” the second feature, “under” the second feature, and “below” it, implies that the first feature is below the second feature, or simply indicates that the level of the first feature is lower than that of the second feature.

[0040] The following disclosure provides several different embodiments or examples for implementing different structures of this disclosure. For the sake of simplicity, components and settings are described in specific examples below. These are, of course, merely examples and are not intended to limit this disclosure. Furthermore, reference symbols in numerical and / or letter form may be repeated in several examples in this disclosure, and such repetition serves for simplification and clarity and does not indicate any relationship between the various embodiments and / or settings discussed. In addition, this disclosure provides examples of various specific processes and materials; however, those skilled in the art may implement other processes and / or use other materials.

[0041] According to this revelation, a first tower base structure and a second tower base structure are arranged in a composite, increasing the complexity of the surface morphology of a first region, thereby enhancing the photovoltaic response and the mechanical strength of a solar cell. Design 1

[0042] According to the representations in Fig. 1 to Fig. 3 This embodiment provides a solar cell which includes the following: a silicon substrate that includes a first region, wherein the first region is provided with a plurality of first tower base structures 101 and a plurality of second tower base structures 102, wherein at least some of the second tower base structures 102 are arranged on the first tower base structures 101.

[0043] The tower base structures refer to microstructures arranged on the silicon substrate of the solar cell. Typically, these microstructures have the appearance of towers or cones with a flat top surface and a polygonal outer contour, and in particular include at least one of the following shapes: a rhombus shape, a square, a trapezoid, an approximate rhombus shape, an approximate square, and an approximate trapezoid. The first tower base structures 101 and the second tower base structures 102 are formed on the first region of the silicon substrate by a specific process, with at least some of the second tower base structures 102 being located on the top surfaces of the first tower base structures 101.

[0044] The composite arrangement of the first tower base structures 101 and the second tower base structures 102 can specifically be a parallel arrangement of the second tower base structures 102 and the first tower base structures 101, or the second tower base structures 102 can be arranged on the upper surfaces of the first tower base structures 101. This arrangement method provides a more complex surface morphology, which facilitates the deposition and formation of subsequent films on the silicon substrate.

[0045] Due to the composite arrangement of the first tower base structures 101 and the second tower base structures 102, the complexity of the surface morphology of the first region is increased. The presence of the first tower base structures 101 and the second tower base structures 102 causes multiple reflections and scatterings of incident light on the surface of the silicon substrate, thereby increasing the optical path of the light within the silicon substrate. In particular, diffusely reflected light from the rear side undergoes multiple reflections by the structures of the first tower base structures 101 and the second tower base structures 102, so that it is absorbed more effectively by the silicon substrate. With an increasing optical path, the path length of photons within the silicon substrate becomes longer, thereby increasing the absorption probability and thus enhancing the photoelectric response of the solar cell.

[0046] The composite textures of the first tower base structures 101 and the second tower base structures 102 can also provide superior surface features, enabling the screen-printed metal paste to better fill the spaces between the tower base structures during electrode assembly. This improved contact characteristic reduces the contact resistance between the electrode and the silicon substrate, thereby increasing the open-circuit voltage and cell fill factor.

[0047] Structurally, the composite arrangement of the first tower base structures 101 and the second tower base structures 102 facilitates the dissipation and reduction of stress generated during the growth of a polycrystalline silicon film on a silicon wafer under high-temperature conditions. Stacking the first tower base structures 101 and the second tower base structures 102 can provide multi-stage stress relief pathways, thereby reducing stress concentration phenomena. By optimizing the shape and distribution of the tower base structures, the overall stress on the silicon wafer can be effectively reduced, thus minimizing the degree of warping under high-temperature conditions.Thanks to the improved stress distribution and reduced curvature of the silicon wafer, the silicon wafer is less susceptible to mechanical damage such as chipping, scratches and edge breakage during the automated production and transport process, thus improving production efficiency and product quality.

[0048] In this embodiment, the photoelectric response and the mechanical strength of the solar cell can be enhanced by arranging the first tower base structures 101 and the second tower base structures 102 on the silicon substrate. Design 2

[0049] Based on embodiment 1, the longest diagonal length of the first tower base structures 101 is greater than or equal to 2 µm and less than or equal to 60 µm.

[0050] Since the top surface of a tower base is typically polygonal, the longest diagonal line refers to a diagonal line with the maximum length. Experimental tests show that the shape of the top surface of the tower base is not excessively elongated. In general, the longer the longest diagonal line, the larger the area of ​​the top surface of the tower base.

[0051] When the longest diagonal length of the tower base is measured, a film surface can be directly measured for calibration using test instruments such as an optical microscope, an atomic force microscope, a scanning electron microscope, and a transmission electron microscope.

[0052] Furthermore, by limiting the longest diagonal size of the first tower base structures 101, the tower base structures are optimized. The optimized tower base structures can not only effectively relieve stresses and reduce mechanical damage, but also further improve the passivation quality and electrode contact properties in the first region, thereby increasing the open-circuit voltage and fill factor, and ultimately improving the overall conversion efficiency of the cell. embodiment 3

[0053] Based on embodiment 1, the longest diagonal length of the first tower base structures 101 is greater than or equal to 5 µm and less than or equal to 40 µm.

[0054] Furthermore, by limiting the longest diagonal size of the first tower base structures 101, the tower base structures are optimized. The optimized tower base structures can not only effectively relieve stresses and reduce mechanical damage, but also further improve the passivation quality and electrode contact properties in the first region, thereby increasing the open-circuit voltage and fill factor, and ultimately improving the overall conversion efficiency of the cell. Design 4

[0055] Based on embodiment 1, the longest diagonal length of the first tower base structures 101 is greater than or equal to 10 µm and less than or equal to 30 µm.

[0056] Furthermore, by limiting the longest diagonal size of the first tower base structures 101, the tower base structures are optimized. The optimized tower base structures can not only effectively relieve stresses and reduce mechanical damage, but also further improve the passivation quality and electrode contact properties in the first region, thereby increasing the open-circuit voltage and fill factor, and ultimately improving the overall conversion efficiency of the cell. Design 5

[0057] Based on embodiment 1, the longest diagonal length of the first tower base structures 101 is greater than or equal to 15 µm and less than or equal to 30 µm.

[0058] Furthermore, by limiting the longest diagonal size of the first tower base structures 101, the tower base structures are optimized. The optimized tower base structures can not only effectively relieve stresses and reduce mechanical damage, but also further improve the passivation quality and electrode contact properties in the first region, thereby increasing the open-circuit voltage and fill factor, and ultimately improving the overall conversion efficiency of the cell. Design 6

[0059] Based on embodiment 1, the longest diagonal length of the second tower base structures 102 is greater than or equal to 0.5 µm and less than or equal to 30 µm.

[0060] Furthermore, by limiting the longest diagonal size of the second tower base structures 102, the tower base structures are optimized. The optimized tower base structures can not only effectively relieve stresses and reduce mechanical damage, but also further improve the passivation quality and electrode contact properties in the first region, thereby increasing the open-circuit voltage and fill factor, and ultimately improving the overall conversion efficiency of the cell. Model 7

[0061] Based on embodiment 1, the longest diagonal length of the second tower base structures 102 is greater than or equal to 1 µm and less than or equal to 30 µm.

[0062] Furthermore, by limiting the longest diagonal size of the second tower base structures 102, the tower base structures are optimized. The optimized tower base structures can not only effectively relieve stresses and reduce mechanical damage, but also further improve the passivation quality and electrode contact properties in the first region, thereby increasing the open-circuit voltage and fill factor, and ultimately improving the overall conversion efficiency of the cell. Design 8

[0063] Based on embodiment 1, the longest diagonal length of the second tower base structures 102 is greater than or equal to 1 µm and less than or equal to 20 µm.

[0064] Furthermore, by limiting the longest diagonal size of the second tower base structures 102, the tower base structures are optimized. The optimized tower base structures can not only effectively relieve stresses and reduce mechanical damage, but also further improve the passivation quality and electrode contact properties in the first region, thereby increasing the open-circuit voltage and fill factor, and ultimately improving the overall conversion efficiency of the cell. Design 9

[0065] Based on embodiment 1, the longest diagonal length of the second tower base structures 102 is greater than or equal to 5 µm and less than or equal to 20 µm.

[0066] Furthermore, by limiting the longest diagonal size of the second tower base structures 102, the tower base structures are optimized. The optimized tower base structures can not only effectively relieve stresses and reduce mechanical damage, but also further improve the passivation quality and electrode contact properties in the first region, thereby increasing the open-circuit voltage and fill factor, and ultimately improving the overall conversion efficiency of the cell. Design 10

[0067] Based on one of the embodiments of embodiment 5 to embodiment 10, a total area of ​​the plurality of second tower base structures 102 constitutes more than 60% of an area of ​​the first region.

[0068] Embodiments 5 to 10 define the longest diagonal length of the second tower base structures 102. Not all second tower base structures 102 within the first region need necessarily conform to defined sizes, and it is sufficient that the sum of the areas of all second tower base structures 102 that conform to the defined sizes is greater than 60% of the total area of ​​the first region. In particular, if the total area of ​​the first region is A, the sum of the areas of all second tower base structures 102 that conform to the defined sizes is greater than 0.6 A, thus ensuring sufficiently comprehensive coverage of the second tower base structures 102 within the first region to achieve the desired optimization effects. Design 11

[0069] Based on embodiment 1, the solar cell further includes a second region, and the second region and the first region are located on the same side of the silicon substrate or on two opposite sides of the silicon substrate.

[0070] In particular, both the first region and the second region are located on the same surface of the silicon substrate, meaning that the two regions exist side by side on the same surface, ideally adjacent to each other, or distributed across the surface in a specific manner. Alternatively, the first region and the second region are located on opposite sides of the silicon substrate, meaning that one region is located on a front surface of the silicon substrate and the other region is located on a rear surface of the silicon substrate. Design 12

[0071] According to the representations in Fig. 5 to Fig. 7 is the second region based on embodiment 12 provided with a plurality of third tower base structures 103, wherein Fig. 6 and Fig. 7 each show scanning electron microscope images of the third tower base structures 103 in a first angle and a third angle.

[0072] The arrangement of the third tower base structures 103 increases the complexity of the surface morphology of the second region, thereby allowing a passivation layer to cover the third tower base structures 103 more uniformly. This covering can effectively reduce the surface density and recombination rate, thus improving the passivation quality.

[0073] The third tower base structures 103 can also provide superior surface features, enabling the screen-printed metal paste to better fill the spaces between the tower base structures during electrode assembly. This improved contact characteristic reduces the contact resistance between the electrode and the silicon substrate, thereby increasing the open-circuit voltage and the cell's fill factor.

[0074] The third tower base structures 103 can also be downwardly curved structures. It should be noted that, when considering the example of the third tower base structures 103 arranged on a surface of the second region of the silicon substrate, the downwardly curved structures can be understood as being curved downwards into the second region.

[0075] In some optional implementations, the depth of a downward bulge in the third tower base structures is greater than or equal to 0.05 µm and less than or equal to 1.5 µm. As shown in Fig. 6, the depth of the downward curvature of the third tower base structures 103 is, for example, 556 µm. embodiment 13

[0076] Based on embodiment 13, the longest diagonal length of the third tower base structures 103 is greater than or equal to 2 µm and less than or equal to 60 µm.

[0077] Furthermore, by limiting the longest diagonal size of the third tower base structures 103, the tower base structures are optimized. The optimized tower base structures can not only effectively relieve stresses and reduce mechanical damage, but also further improve the passivation quality and electrode contact properties in the second region, thereby increasing the open-circuit voltage and fill factor, and ultimately improving the overall conversion efficiency of the cell. embodiment 14

[0078] Based on embodiment 13, the longest diagonal length of the third tower base structures 103 is greater than or equal to 5 µm and less than or equal to 40 µm.

[0079] Furthermore, by limiting the longest diagonal size of the third tower base structures 103, the tower base structures are optimized. The optimized tower base structures can not only effectively relieve stresses and reduce mechanical damage, but also further improve the passivation quality and electrode contact properties in the second region, thereby increasing the open-circuit voltage and fill factor, and ultimately improving the overall conversion efficiency of the cell. Design 15

[0080] Based on embodiment 13, the longest diagonal length of the third tower base structures 103 is greater than or equal to 10 µm and less than or equal to 30 µm.

[0081] Furthermore, by limiting the longest diagonal size of the third tower base structures 103, the tower base structures are optimized. The optimized tower base structures can not only effectively relieve stresses and reduce mechanical damage, but also further improve the passivation quality and electrode contact properties in the second region, thereby increasing the open-circuit voltage and fill factor, and ultimately improving the overall conversion efficiency of the cell. Design 16

[0082] Based on embodiment 13, the longest diagonal length of the third tower base structures 103 is greater than or equal to 15 µm and less than or equal to 30 µm.

[0083] Furthermore, by limiting the longest diagonal size of the third tower base structures 103, the tower base structures are optimized. The optimized tower base structures can not only effectively relieve stresses and reduce mechanical damage, but also further improve the passivation quality and electrode contact properties in the second region, thereby increasing the open-circuit voltage and fill factor, and ultimately improving the overall conversion efficiency of the cell. embodiment 17

[0084] Based on embodiment 1, the longest diagonal length of the first tower base structures 101 is greater than the longest diagonal length of the second tower base structures 102.

[0085] The longest diagonal length of the first tower base structures 101 is greater than the longest diagonal length of the second tower base structure 102, meaning that the size of the first tower base structures 101 is larger than that of the second tower base structures 102. The larger first tower base structures 101 facilitate stress distribution on the silicon substrate, thereby reducing the stress concentration phenomenon. The smaller second tower base structures 102 can better adapt to changes in surface morphology, thus reducing the risk of mechanical damage. Furthermore, the larger first tower base structures 101 provide a larger coverage area for the passivation layer, thereby improving the passivation quality.The smaller second tower base structures 102 can better touch the electrode, thereby reducing the contact resistance and increasing the open-circuit voltage and the fill factor of the cell. Design 18

[0086] Based on embodiment 13, the ratio of the longest diagonal length of the first tower base structures 101 to the longest diagonal length of the third tower base structures 103 is in the range of 0.5 to 2.

[0087] The longest diagonal length of the third tower base structures 103 can be greater than or equal to 0.5 times the longest diagonal length of the first tower base structures 101 and less than or equal to 2 times the longest diagonal length of the first tower base structures 101. The design specifies a particular proportional relationship between the longest diagonal lengths of the first tower base structures 101 and the third tower base structures 103 to ensure that the tower base structures in the two regions can work together cooperatively while leveraging their respective advantages. Design 19

[0088] Based on embodiment 12, the roughness of the first region is greater than that of the second region.

[0089] Surface roughness refers to the degree of microscopic unevenness of a surface, with higher roughness indicating more microscopic bumps or depressions. High surface roughness in the first region means that the surface of that region is more uneven and has more microstructures. Low surface roughness in the second region indicates a relatively smooth and flat surface.

[0090] Different surface roughness designs can effectively improve the efficiency of photoelectric conversion, optimize electrode contact properties, reduce surface composition effects, and contribute to increased mechanical performance. Design 20

[0091] According to the representation in Fig. 1, based on embodiment 1, the plurality of first tower base structures 101 are arranged in a linear series.

[0092] The multitude of first tower base structures 101 are arranged in a regular linear row within the first region. This means that the first tower base structures 101 are arranged in a specific direction with a specific spacing and regularity, thus forming a clean linear structure. The linear row arrangement of the first tower base structures 101 can be determined according to design requirements, including parameters such as spacing, arrangement direction, and row density, in order to achieve optimal performance.

[0093] The arrangement method allows the voltage to be distributed evenly, improves the simplicity and uniformity of the manufacturing process, and further optimizes the overall performance and reliability of the solar cell. Design 21

[0094] According to the representation in Fig. 5, based on embodiment 1, the plurality of third tower base structures 101 are arranged in a linear series.

[0095] The multitude of third tower base structures 103 are arranged in a regular linear row within the second region. This means that the first tower base structures 103 are arranged in a specific direction with a specific spacing and regularity, thus forming a clean linear structure. The linear row arrangement of the third tower base structures 103 can be determined according to design requirements, including parameters such as spacing, arrangement direction, and row density, in order to achieve optimal performance.

[0096] The arrangement method allows the voltage to be distributed evenly, improves the simplicity and uniformity of the manufacturing process, and further optimizes the overall performance and reliability of the solar cell. Design 22

[0097] Based on embodiment 1 and embodiment 12, the first tower base structures 101 and / or the second tower base structures 102 are downwardly curved structures. That is, the first tower base structures 101 and / or the second tower base structures 102 have downwardly curved sections.

[0098] In particular, the first tower base structures 101 and the second tower base structures 102 are vaulted, or either the first tower base structures 101 or the second tower base structures 102 are vaulted.

[0099] According to the representation in Fig. 4 are the first tower base structures 101, which are downwardly curved structures. It should be noted that, when considering the example of the first tower base structures 101, which are arranged on a surface of the first region of the silicon substrate, the downwardly curved structures can be understood as meaning that the first tower base structures 101 are curved downwards into the first region.

[0100] In some optional implementations, the depth of a downward bulge of the first tower base structures and / or the second tower base structures is greater than or equal to 0.05 µm and less than or equal to 2 µm. As shown in Fig. 4 The depth of the downward curvature of the first tower base structures 101 is, for example, 1.01 µm. embodiment 23

[0101] This embodiment provides a cell assembly comprising the solar cell according to one of the above embodiments.

[0102] The advantageous effects achieved by the cell assembly in this embodiment are similar to those of the solar cell, which are not repeated here. embodiment 24

[0103] This embodiment provides a photovoltaic system comprising the cell assembly from embodiment 23.

[0104] The advantageous effects achieved by the photovoltaic system in this embodiment are similar to those of the solar cell, which are not repeated here.

[0105] The above descriptions are merely preferred embodiments of this disclosure and are not intended to limit it. All modifications, equivalent replacements, improvements, etc., carried out according to the concept and principle of this disclosure are covered by the scope of protection of this disclosure. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] CN 202410950720.8

[0001]

Claims

[1] Solar cell, comprising: a silicon substrate comprising a first region, wherein the first region is provided with a plurality of first tower base structures and a plurality of second tower base structures, wherein at least some of the second tower base structures are arranged on the first tower base structures. [2] Solar cell according to claim 1, wherein a longest diagonal length of the first tower base structures is greater than or equal to 2 µm and less than or equal to 60 µm or a longest diagonal length of the first tower base structures is greater than or equal to 5 µm and less than or equal to 40 µm or a longest diagonal length of the first tower base structures is greater than or equal to 10 µm and less than or equal to 30 µm or a longest diagonal length of the first tower base structures is greater than or equal to 15 µm and less than or equal to 30 µm. [3] Solar cell according to claim 1, wherein a longest diagonal length of the second tower base structures is greater than or equal to 0.5 µm and less than or equal to 30 µm or a longest diagonal length of the second tower base structures is greater than or equal to 1 µm and less than or equal to 30 µm or a longest diagonal length of the second tower base structures is greater than or equal to 1 µm and less than or equal to 20 µm or The longest diagonal length of the second tower base structures is greater than or equal to 5 µm and less than or equal to 20 µm. [4] Solar cell according to claim 2 or 3, wherein a ratio of a total area of ​​orthographic projections of the second tower base structures on the first region to an area of ​​the first region is greater than 60%. [5] Solar cell according to claim 1, further comprising a second region, wherein the second region and the first region are located on the same side of the silicon substrate or on two opposite sides of the silicon substrate. [6] Solar cell according to claim 5, wherein the second region is provided with a plurality of third tower base structures. [7] Solar cell according to claim 6, wherein a longest diagonal length of the third tower base structures is greater than or equal to 2 µm and less than or equal to 60 µm or a longest diagonal length of the third tower base structures is greater than or equal to 5 µm and less than or equal to 40 µm or The longest diagonal length of the third tower base structures is greater than or equal to 10 µm and less than or equal to 30 µm. [8] Solar cell according to claim 1, wherein a longest diagonal length of the first tower base structures is greater than a longest diagonal length of the second tower base structures. [9] Solar cell according to claim 6, wherein the ratio of the longest diagonal length of the first tower base structures to the longest diagonal length of the third tower base structures is in the range of 0.5 to 2. [10] Solar cell according to claim 5, wherein the roughness of the first region is greater than the roughness of the second region. [11] Solar cell according to claim 1, wherein the plurality of first tower base structures are arranged in a linear series. [12] Solar cell according to claim 6, wherein the plurality of third tower base structures are arranged in a linear series. [13] Solar cell according to claim 1, wherein the first tower base structures are downwardly curved structures or the second tower base structures are downwardly curved structures or the first tower base structures and the second tower base structures are downwardly curved structures. [14] Solar cell according to claim 13, wherein a depth of a downward curvature of the first tower base structures is greater than or equal to 0.05 µm and less than or equal to 2 µm, or a depth of a downward curvature of the second tower base structures is greater than or equal to 0.05 µm and less than or equal to 2 µm, or a depth of a downward curvature of the first tower base structures and a depth of a downward curvature of the second tower base structures are greater than or equal to 0.05 µm and less than or equal to 2 µm. [15] Solar cell according to claim 6, wherein the third tower base structures are downwardly curved structures. [16] Solar cell according to claim 15, wherein the depth of a downward curvature of the third tower base structures is greater than or equal to 0.05 µm and less than or equal to 1.5 µm. [17] Cell assembly comprising the solar cell according to any one of claims 1 to 16. [18] Photovoltaic system comprising the cell assembly according to claim 17.

Images