Solar cells, photovoltaic modules and photovoltaic systems

Abstract

The present application relates to a solar cell, a photovoltaic module, and a photovoltaic system. The solar cell includes a cell and an electrode grid structure arranged on the surface of the cell; the electrode grid structure includes a main grid and a fine grid; the main grid includes a plurality of main grid lines arranged on the surface of the cell, the plurality of main grid lines extending along a first direction and spaced apart along a second direction, at least one main grid line includes a plurality of main grid segments spaced apart along the first direction, and gaps are formed between adjacent main grid segments; the fine grid includes a plurality of fine grid lines extending along the second direction and spaced apart along the first direction; the plurality of fine grid lines and the plurality of main grid lines are in a grid-like shape intersecting; the plurality of main grid segments and the plurality of fine grid lines are alternately arranged in the first direction; each fine grid line passes through a corresponding gap and is connected to an adjacent main grid segment. In this way, the fine grid can better collect current, which is beneficial to improving the fill factor of the solar cell, thereby improving the conversion efficiency of the solar cell.

Description

Technical Field

[0001] The present application relates to the field of photovoltaic technology, and in particular to a solar cell, a photovoltaic module and a photovoltaic system. Background Art

[0002] Solar cells, also known as photovoltaic cells, are semiconductor devices that convert sunlight directly into electricity. Because they are environmentally friendly and do not cause environmental pollution, and because solar energy is a renewable resource, solar cells are a promising new type of battery. With the rapid development of solar cells, market competition is becoming increasingly fierce, and the demand for solar cell efficiency is becoming increasingly higher.

[0003] In related technologies, the grid structure of a solar cell consists of main grid lines and fine grid lines (also known as auxiliary grid lines). The fine grid lines are primarily responsible for collecting the current generated by the cell, while the main grid lines are responsible for collecting and transmitting the current collected by the fine grid lines to the outside of the cell. When printing the grid line structure, the main grid is usually printed first, followed by the fine grid lines, with the fine grid lines overlapping the main grid lines. This grid line structure can cause a loss in solar cell efficiency and is detrimental to the development of solar cells. Summary of the Invention

[0004] Based on this, the present application provides a solar cell, a photovoltaic module and a photovoltaic system to improve the conversion efficiency of the solar cell.

[0005] An embodiment of the first aspect of the present application provides a solar cell, comprising a cell and an electrode grid structure arranged on the surface of the cell; the electrode grid structure comprises: a main grid and a fine grid; the main grid comprises a plurality of main grid lines arranged on the surface of the cell, the plurality of main grid lines extending along a first direction and arranged at intervals along a second direction, at least one of the main grid lines comprises a plurality of main grid segments arranged at intervals along the first direction, and gaps are formed between adjacent main grid segments; the first direction and the second direction intersect; the fine grid comprises a plurality of fine grid lines extending along the second direction and arranged at intervals along the first direction; the plurality of fine grid lines and the plurality of main grid lines are in a grid-like shape intersecting the plurality of main grid lines; the plurality of main grid segments and the plurality of fine grid lines are alternately arranged in the first direction; each of the fine grid lines passes through the corresponding gap and is connected to the adjacent main grid segment.

[0006] The solar cell provided by the embodiment of the present application has a plurality of fine grid lines and a plurality of main grid lines arranged in a grid-like manner. At least one main grid line includes a plurality of main grid segments spaced apart along the first direction, gaps are formed between adjacent main grid segments, and the plurality of main grid segments and the plurality of fine grid lines are alternately arranged in the first direction. Each fine grid line passes through a corresponding gap, and each fine grid line is connected to an adjacent main grid segment. As a result, the fine grid lines can directly contact the cell between adjacent main grid segments along the first direction, thereby increasing the direct contact area between the fine grid and the cell, improving the contact between the electrode grid line structure and the cell, and enabling the fine grid to better collect current, thereby improving the fill factor of the solar cell, thereby improving the conversion efficiency of the solar cell, and promoting the development of solar cells.

[0007] In one embodiment, each of the fine gate lines includes a connecting portion and an extending portion; the connecting portion is located between two adjacent main gate segments along the first direction and is connected to both; the extending portion and the connecting portion are staggered along the second direction and are connected to the connecting portion.

[0008] In one embodiment, the main gate segment includes a first end and a second end oppositely disposed along the first direction, and the connecting portion is connected to the first end and the second end adjacent thereto.

[0009] In one embodiment, the connecting portion includes a first sub-portion; the first sub-portion is located between two adjacent main gate segments along the first direction and is connected to both of them; and the extending portion is connected to the first sub-portion.

[0010] In one embodiment, the connecting portion further includes a second sub-portion, which is located on a side of the first sub-portion away from the battery cell, and the orthographic projection of the second sub-portion on the battery cell overlaps with the orthographic projection of the adjacent main grid segment on the battery cell.

[0011] In one embodiment, the spacing between adjacent main gate segments along the first direction is 10 um to 20 um.

[0012] In one embodiment, a dimension of the connecting portion along the second direction is greater than a dimension of the main gate segment along the second direction.

[0013] In one embodiment, the first sub-portion and the extension portion have the same size along the first direction, and the size of the first sub-portion along the first direction is 10 um to 20 um.

[0014] In one embodiment, the size of the second sub-portion along the first direction is 20um-30um.

[0015] In one embodiment, the battery cell includes a substrate, a first doping layer and a first passivation layer stacked in sequence on a first surface of the substrate, and a second passivation layer, a second doping layer and a third passivation layer stacked in sequence on a second surface of the substrate; the first surface and the second surface are arranged opposite to each other.

[0016] An embodiment of the second aspect of the present application provides a photovoltaic assembly, comprising the solar cell according to any of the above embodiments.

[0017] The photovoltaic module provided by the embodiment of the present application includes the solar cell in any of the above embodiments, wherein the multiple fine grid lines of the solar cell and the multiple main grid lines are in a cross-grid shape, and at least one main grid line includes multiple main grid segments spaced apart along the first direction, gaps are formed between adjacent main grid segments, multiple main grid segments and multiple fine grid lines are alternately arranged in the first direction, each fine grid line passes through the corresponding gap, and each fine grid line is connected to the main grid segment adjacent thereto. As a result, the fine grid lines can directly contact the cell between the adjacent main grid segments along the first direction, thereby increasing the direct contact area between the fine grid and the cell, improving the contact between the electrode grid line structure and the cell, and enabling the fine grid to better collect current, which is beneficial to improving the fill factor of the solar cell, thereby improving the conversion efficiency of the solar cell, and further improving the conversion efficiency of the photovoltaic module, which is beneficial to the promotion and application of the photovoltaic module and the development of the photovoltaic industry.

[0018] The third aspect of the present application provides a photovoltaic system comprising a photovoltaic module according to any of the above embodiments, thereby improving the conversion efficiency of the photovoltaic system and facilitating the development of the photovoltaic industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 Schematic diagram of a top view of a solar cell in some embodiments of the present application.

[0020] Figure 2 for Figure 1 Schematic diagram of the structure of the main grid in the solar cell shown in .

[0021] Figure 3 for Figure 1 Schematic diagram of the structure of the connecting portion of the fine grid lines in the solar cell shown in .

[0022] Figure 4 for Figure 1 Schematic diagram of the structure of the cell in the solar cell shown in.

[0023] Description of reference numerals:

[0024] 10. Solar cells;

[0025] 110, battery cell; 111, substrate; 112, first doping layer; 113, first passivation layer; 114, second passivation layer; 115, second doping layer; 116, third passivation layer;

[0026] 120, electrode grid line structure; 121, busbar; 121a, busbar line; 1211, busbar segment; 1211a, first end; 1211b, second end; 1212, notch; 122, fine grid; 122a, fine grid line; 1221, connecting portion; 1221a, first sub-portion; 1221b, second sub-portion; 1222, extension portion;

[0027] X, first direction; Y, second direction. DETAILED DESCRIPTION

[0028] To make the above-mentioned objects, features, and advantages of the present application more clearly understood, the specific embodiments of the present application are described in detail below with reference to the accompanying drawings. The following description sets forth many specific details to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways than those described herein, and those skilled in the art can make similar improvements without violating the scope of the present application. Therefore, the present application is not limited to the specific embodiments disclosed below.

[0029] In the description of this application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0030] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include at least one of such features. In the description of this application, if the term "plurality" appears, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0031] In this application, unless otherwise specified or limited, the terms "mounted," "connected," "connected," "fixed," etc., should be interpreted broadly. For example, these terms may refer to fixed connections, removable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediary; and internal communication between two components or interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of these terms in this application based on the specific circumstances.

[0032] In this application, unless otherwise expressly specified or limited, if a first feature is described as being "above" or "below" a second feature, or similar descriptions, this may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, when a first feature is described as being "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is described as being "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0033] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. If any, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are for illustrative purposes only and do not represent the only embodiment.

[0034] Solar cells, also known as photovoltaic cells, are semiconductor devices that convert sunlight directly into electricity. Because they are environmentally friendly and do not cause environmental pollution, and because solar energy is a renewable resource, solar cells are a promising new type of battery. With the rapid development of solar cells, market competition is becoming increasingly fierce, and the demand for solar cell efficiency is becoming increasingly higher.

[0035] In related technologies, the gridline structure of a solar cell consists of a main gridline and fine gridlines (also known as auxiliary gridlines). The fine gridlines are primarily responsible for collecting the current generated by the cell, while the main gridlines are responsible for collecting and transmitting the current collected by the fine gridlines to the outside of the cell. When printing the gridline structure, the main grid is usually printed first, followed by the fine gridlines. The fine gridlines overlap the main grid, resulting in the fine gridlines not being able to fully contact the cell, causing current loss and, in turn, a loss of solar cell efficiency, which is detrimental to the development of solar cells.

[0036] Based on the above technical problems, the present application provides a solar cell, a photovoltaic module and a photovoltaic system to improve the conversion efficiency of solar cells.

[0037] Figure 1 Schematic diagrams of the top view of solar cells in some embodiments of the present application are shown; Figure 2 A schematic structural diagram of a main grid in a solar cell in some embodiments of the present application is shown.

[0038] See Figure 1 and Figure 2 As shown, an embodiment of the first aspect of the present application provides a solar cell 10, comprising a cell 110 and an electrode grid structure 120 disposed on a surface of the cell 110; the electrode grid structure 120 comprises a main grid 121 and a fine grid 122; the main grid 121 comprises a plurality of main grid lines 121a disposed on the surface of the cell 110, the plurality of main grid lines 121a extending along a first direction X and arranged at intervals along a second direction Y, at least one main grid line 121a comprises a plurality of main grid segments 121 disposed at intervals along the first direction X. 1. A gap 1212 is formed between adjacent main gate segments 1211; the first direction X and the second direction Y intersect; the fine gate 122 includes a plurality of fine gate lines 122a extending along the second direction Y and arranged at intervals along the first direction X; the plurality of fine gate lines 122a and the plurality of main gate lines 121a are arranged in a grid-like manner; the plurality of main gate segments 1211 and the plurality of fine gate lines 122a are alternately arranged in the first direction X; each fine gate line 122a passes through a corresponding gap 1212 and is connected to an adjacent main gate segment 1211.

[0039] The solar cell 10 provided in the embodiment of the present application has a plurality of fine grid lines 122a and a plurality of main grid lines 121a in a cross-grid shape, and at least one main grid line 121a includes a plurality of main grid segments 1211 spaced apart along the first direction X, and gaps 1212 are formed between adjacent main grid segments 1211. The plurality of main grid segments 1211 and the plurality of fine grid lines 122a are alternately arranged in the first direction X, each fine grid line 122a passes through the corresponding gap 1212, and each fine grid line 122a is connected to the main grid segment 1211 adjacent to it. Therefore, the fine grid line 122a can directly contact the battery cell 110 between the main grid segments 1211 adjacent along the first direction X, thereby increasing the direct contact area between the fine grid 122 and the battery cell 110, improving the contact between the electrode grid line structure 120 and the battery cell 110, and enabling the fine grid 122 to better collect current, which is beneficial to improving the fill factor of the solar cell 10, and further improving the conversion efficiency of the solar cell 10, which is beneficial to the development of solar cells.

[0040] like Figure 1As shown, in one embodiment, each fine gate line 122a includes a connecting portion 1221 and an extension portion 1222; the connecting portion 1221 is located between two adjacent main gate segments 1211 along the first direction X and is connected to both; the extension portion 1222 is arranged alternately with the connecting portion 1221 along the second direction Y and is connected to the connecting portion 1221.

[0041] Specifically, if Figure 1 and Figure 2 As shown, if all the main grid lines 121a include a plurality of main grid segments 1211 spaced apart along the first direction X; the connecting portion 1221 is located between two adjacent main grid segments 1211 along the first direction X and is connected to both; the connecting portions 1221 adjacent to each other along the second direction Y are connected via an extension portion 1222. In this way, each fine grid line 122a does not need to be overlapped on the main grid line 121a, and it is also possible to ensure that each fine grid line 122a is connected to all the main grid lines 121a. Moreover, the fine grid line 122a is in direct contact with the cell 110, so that the fine grid line 122a preferentially contacts the doped region, can better collect current, reduce current loss caused by overlap, improve the contact between the electrode grid line structure 120 and the cell 110, improve the fill factor, and thus improve the conversion efficiency of the solar cell 10.

[0042] like Figure 1 and Figure 2 As shown, in one embodiment, the main gate segment 1211 includes a first end 1211a and a second end 1211b that are oppositely disposed along a first direction X, and the connecting portion 1221 is connected to the first end 1211a and the second end 1211b adjacent thereto. Thus, by connecting the connecting portion 1221 to the first end 1211a and the second end 1211b adjacent thereto, the connection between the connecting portion 1221 and the main gate segment 1211 is facilitated, thereby facilitating the connection between the fine gate line 122a and the main gate line 121a.

[0043] like Figure 1 and Figure 3 As shown, in one embodiment, the connecting portion 1221 includes a first sub-portion 1221a; the first sub-portion 1221a is located between and connects two adjacent busbar segments 1211 along the first direction X; and the extension portion 1222 is connected to the first sub-portion 1221a. Thus, the first sub-portion 1221a facilitates the connection between the connecting portion 1221 and the busbar segments 1211.

[0044] like Figure 1 and Figure 3As shown, in one embodiment, the connecting portion 1221 further includes a second sub-portion 1221b, which is located on the side of the first sub-portion 1221a facing away from the cell 110. The orthographic projection of the second sub-portion 1221b on the cell 110 overlaps with the orthographic projection of the adjacent main grid segment 1211 on the cell 110. Thus, the second sub-portion 1221b can ensure a reliable connection between the connecting portion 1221 and the adjacent main grid segment 1211, so that the fine grid lines 122a can better collect current. The current collected by the fine grid lines 122a is then collected and transmitted to the outside of the cell through the main grid lines 121a, thereby improving the conversion efficiency of the solar cell 10.

[0045] like Figure 1 and Figure 2 As shown, in one embodiment, the spacing between adjacent main grid segments 1211 along the first direction X is 10um to 20um. That is, the size of the notch 1212 along the first direction X is 10um to 20um, and the minimum size of the connecting portion 1221 along the first direction X can be 10um to 20um. In this way, the connecting portion 1221 and the adjacent first end 1211a and second end 1211b can be effectively connected, thereby ensuring the effective connection between the fine grid line 122a and the main grid segment 1211, and further ensuring the effective connection between the fine grid line 122a and the main grid line 121a, thereby ensuring the conversion efficiency of the solar cell 10.

[0046] like Figure 1 As shown, in one embodiment, the dimension of the connecting portion 1221 along the second direction Y is greater than the dimension of the busbar segment 1211 along the second direction Y. In other words, the dimension of the connecting portion 1221 along the second direction Y is greater than the line width of the busbar line 121a. In this way, a reliable connection between the connecting portion 1221 and the adjacent busbar segment 1211 can be ensured, thereby ensuring an effective connection between the fine grid line 122a and the busbar line 121a, thereby ensuring the conversion efficiency of the solar cell 10.

[0047] like Figures 1 to 3 As shown, in one embodiment, the first sub-portion 1221a and the extension portion 1222 have the same size along the first direction X, and the size of the first sub-portion 1221a along the first direction X is 10 μm to 20 μm. In other words, the size of the first sub-portion 1221a and the extension portion 1222 along the first direction X can be the same as the size of the notch 1212 along the first direction X. In this way, a reliable connection between the first sub-portion 1221a and the adjacent busbar segment 1211 can be ensured, thereby ensuring an effective connection between the fine grid lines 122a and the busbar lines 121a, thereby ensuring the conversion efficiency of the solar cell 10.

[0048] like Figure 1 and Figure 3As shown, in one embodiment, the size of the second sub-portion 1221b along the first direction X is 20um to 30um. In other words, the size of the second sub-portion 1221b along the first direction X is larger than the size of the notch 1212 along the first direction X. In this way, it is ensured that the two ends of the second sub-portion 1221b along the first direction X can be overlapped on the corresponding main grid segment 1211, thereby ensuring a reliable connection between the connecting portion 1221 and the adjacent main grid segment 1211, so that the fine grid line 122a can better collect current, and the current collected by the fine grid line 122a is collected and transmitted to the outside of the battery through the main grid line 121a, thereby improving the conversion efficiency of the solar cell 10.

[0049] like Figure 4 As shown, in one embodiment, the battery cell 110 includes a substrate 111, a first doping layer 112 and a first passivation layer 113 stacked in sequence on the first side of the substrate 111, and a second passivation layer 114, a second doping layer 115 and a third passivation layer 116 stacked in sequence on the second side of the substrate 111; the first side and the second side are arranged opposite to each other.

[0050] It should be noted that the first doping layer 112 may have a doping type opposite to that of the substrate 111. The second passivation layer 114 includes a tunneling oxide layer and includes at least one of silicon oxide and aluminum oxide. The second doping layer 115 is a doped polysilicon layer and may have the same doping type as the substrate 111.

[0051] In one embodiment, the material of the first passivation layer 113 and the third passivation layer 116 may include at least one of aluminum oxide, silicon nitride, silicon oxide, gallium oxide, aluminum nitride, and silicon oxynitride.

[0052] An embodiment of the second aspect of the present application provides a photovoltaic assembly, comprising the solar cell 10 according to any of the above embodiments.

[0053] The photovoltaic module provided by the embodiment of the present application includes the solar cell 10 described in the first aspect, and the multiple fine grid lines 122a of the solar cell 10 are in a cross grid shape with the multiple main grid lines 121a. At least one main grid line 121a includes multiple main grid segments 1211 arranged at intervals along the first direction X, and gaps 1212 are formed between adjacent main grid segments 1211. The multiple main grid segments 1211 and the multiple fine grid lines 122a are alternately arranged in the first direction X, each fine grid line 122a passes through the corresponding gap 1212, and each fine grid line 122a is connected to the main grid segment 1211 adjacent to it. Therefore, the fine grid line 122a can directly contact the battery cell 110 between the main grid segments 1211 adjacent along the first direction X, thereby increasing the direct contact area between the fine grid 122 and the battery cell 110, improving the contact between the electrode grid line structure 120 and the battery cell 110, and enabling the fine grid 122 to better collect current, which is beneficial to improving the fill factor of the solar cell 10, thereby improving the conversion efficiency of the solar cell 10, and further improving the conversion efficiency of the photovoltaic module, which is beneficial to the promotion and application of photovoltaic modules and the development of the photovoltaic industry.

[0054] The third aspect of the present application provides a photovoltaic system comprising a photovoltaic module according to any of the above embodiments, thereby improving the conversion efficiency of the photovoltaic system and facilitating the development of the photovoltaic industry.

[0055] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0056] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present patent application shall be determined by the appended claims.

Claims

1. A solar cell, characterized in that: It includes a battery cell and an electrode grid line structure arranged on the surface of the battery cell; the electrode grid line structure includes: A busbar, comprising a plurality of busbar lines disposed on a surface of the cell, the plurality of busbar lines extending along a first direction and spaced apart along a second direction, at least one of the busbar lines comprising a plurality of busbar segments spaced apart along the first direction, with through-notches formed between adjacent busbar segments; the first direction and the second direction intersecting; a fine grid, comprising a plurality of fine grid lines extending along the second direction and arranged at intervals along the first direction; the plurality of fine grid lines and the plurality of main grid lines forming a grid pattern that intersects; the plurality of main grid segments and the plurality of fine grid lines being alternately arranged in the first direction; each of the fine grid lines passing through a corresponding through-notch and connected to an adjacent main grid segment; Each of the fine gate lines includes a connecting portion and an extending portion; the connecting portion is located between two adjacent main gate segments along the first direction and is connected to both of them; the extending portion is staggered with the connecting portion along the second direction and is connected to the connecting portion; The connecting portion includes a first sub-portion; the first sub-portion is located between two adjacent main gate segments along the first direction and is connected to both; the extending portion is connected to the first sub-portion; The connecting portion further includes a second sub-portion, which is located on a side of the first sub-portion away from the battery cell. The orthographic projection of the second sub-portion on the battery cell overlaps with the orthographic projection of the adjacent main grid segment on the battery cell.

2. The solar cell according to claim 1, wherein The main gate segment includes a first end and a second end opposite to each other along the first direction, and the connecting portion is connected to the first end and the second end adjacent thereto.

3. The solar cell according to claim 1, wherein The distance between the adjacent main gate segments along the first direction is 10um to 20um.

4. The solar cell according to claim 1, wherein A dimension of the connecting portion along the second direction is greater than a dimension of the main gate segment along the second direction.

5. The solar cell according to claim 1, wherein The first sub-portion and the extending portion have the same size along the first direction, and the size of the first sub-portion along the first direction is 10 um to 20 um.

6. The solar cell according to claim 1, wherein The size of the second sub-portion along the first direction is 20um-30um.

7. The solar cell according to claim 1, wherein The cell comprises a substrate, a first doping layer and a first passivation layer stacked sequentially on a first surface of the substrate, and a second passivation layer, a second doping layer and a third passivation layer stacked sequentially on a second surface of the substrate; the first surface and the second surface are arranged opposite to each other.

8. A photovoltaic module, characterized in that: The solar cell according to any one of claims 1 to 7 is included.

9. A photovoltaic system, characterized in that: Comprising the photovoltaic module according to claim 8.

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