Solar cells and photovoltaic assemblies

Abstract

This disclosure is applicable to the field of photovoltaic technology and provides a solar cell and a photovoltaic assembly, the solar cell comprising a silicon wafer and a fine grid provided on the silicon wafer, the fine grid comprising a first fine grid and a second fine grid alternately distributed along a first direction, the silicon wafer having a first edge, a second edge, a third edge and a fourth edge, a first inclined edge connecting the first edge and the third edge, a first connecting line adjacent to the first inclined edge and the first connecting line connected to the first fine grid or the second fine grid, the distance between the first inclined edge and the intersection of the first edge and the third edge being 2.5 millimeters or less, and the number of first fine grids or second fine grids connected to the first connecting line being 4 or less. By making the first inclined edge small and further shortening the first connecting line located on the first inclined edge, and by making it possible to connect only 4 or fewer first fine grids or second fine grids, the light-receiving area of ​​the cell is secured as much as possible and the conversion efficiency of the cell is secured.

Description

Cross - reference to related applications

[0001] This disclosure claims priority from a Chinese patent application with application number 202420895917.1, titled "Back - contact solar cell without bus bar, battery assembly and photovoltaic system", filed with the China National Intellectual Property Administration on April 26, 2024, and a Chinese patent application with application number 202411028463.9, titled "Solar cell and photovoltaic assembly", filed with the China National Intellectual Property Administration on July 29, 2024. All of its content is incorporated herein by reference.

Technical Field

[0002] This disclosure belongs to the field of photovoltaic power generation technology, and particularly relates to solar cells and photovoltaic assemblies.

Background Art

[0003] A solar cell is a device that directly converts light energy into electrical energy by the photovoltaic effect. Crystalline silicon cells use a silicon wafer as a substrate and are divided into P - type cells and N - type cells according to the difference in silicon wafers. There is no essential difference in the power generation principles of these two types of cells, and both are based on the separation of optical carriers by a PN junction.

[0004] In the production process of solar cells, by cutting and smoothing the crystal columns, sheets of appropriate size and shape can be obtained. After subsequent processes such as etching, polishing, cleaning, and evaluation, qualified silicon wafers can be obtained. For a silicon wafer, the size of the front (light - receiving surface) of the silicon wafer plays an important role in the power generation conversion efficiency. It is optimal to adopt a square silicon wafer. Also, when the oriented silicon wafers form a square lattice, the gap between adjacent silicon wafers is very small, without gaps, ensuring the power generation efficiency.

[0005] Conventional silicon wafers are chamfered, and the chamfered edges of the silicon wafer have relatively low central stress, making them stronger. However, the chamfering of conventional silicon wafers is usually made large, which reduces the surface area of ​​the silicon wafer that receives light, affecting power generation efficiency. [Overview of the project] [Problems that the invention aims to solve]

[0006] The embodiments of this disclosure provide solar cells and photovoltaic assemblies intended to solve the problem that the small surface area of ​​conventional solar cells affects power generation efficiency. [Means for solving the problem]

[0007] The embodiments of this disclosure are implemented as follows, and the solar cell is The silicon wafer comprises a silicon wafer having a few fine grids, the fine grids comprising a first fine grid and a second fine grid that are alternately distributed along a first direction. Silicon wafers are A first edge and a second edge are provided opposite to each other along a second direction that is perpendicular to the first direction, and a third edge and a fourth edge are provided opposite to each other along the first direction, A first beveled edge connects the first edge and the third edge, A first connecting line provided adjacent to a first inclined edge, having a first connecting line connected to at least one first thin grid or at least one second thin grid, The intersection of the first inclined edge and the first edge is the first intersection, the intersection of the first inclined edge and the third edge is the second intersection, the distance between the first intersection and the second intersection is 2.5 millimeters or less, and the number of first thin grids or second thin grids connected to the first connecting line is 4 or less.

[0008] In some embodiments, the first inclined edge is a straight line or an arc.

[0009] In some embodiments, the first connecting line is not parallel to the first inclined edge.

[0010] In some embodiments, the first connecting wire includes a first connecting portion and a second connecting portion, wherein the width of the first connecting portion is smaller than the width of the second connecting portion.

[0011] In some embodiments, the first connection is connected to the second connection, and the first connection is diagonally marked.

[0012] In some embodiments, the second connection and the first connection are connected by a single thin grid.

[0013] In some embodiments, the second connection and the first connection are parallel to the first direction.

[0014] In some embodiments, the ratio of the width of the narrow grid to the width of the first connecting line is from 1:1.2 to 1:2.

[0015] In some embodiments, the ratio of the width of the thin grid to the width of the first connecting line is 1:1.6 to 1:1.8.

[0016] In some embodiments, the distance between the first intersection and the second intersection is between 0.7 millimeters and 2.5 millimeters.

[0017] In some embodiments, the distance between the first intersection and the second intersection is between 1.2 millimeters and 1.6 millimeters.

[0018] In some embodiments, the silicon wafer includes a second beveled edge connecting the first edge and the fourth edge. The silicon wafer is provided with a second connection line adjacent to the second inclined edge, and the second connection line is connected to at least one first thin grid or at least one second thin grid. The first connection line and the second connection line are connected to a thin grid having the same polarity.

[0019] In some embodiments, the silicon wafer includes a third inclined edge connecting the second edge and the third edge, a third connection line adjacent to the third inclined edge is provided on the silicon wafer, and the third connection line is connected to at least one first thin grid or at least one second thin grid, The first connection line and the third connection line are connected to thin grids having opposite polarities.

[0020] In some embodiments, the angle formed between the first connection line and the second direction is greater than the angle formed between the third connection line and the second direction.

[0021] In some embodiments, the first connection line is connected to the first thin grid, and along the second direction, the distance between the end point adjacent to the first connection line of the second thin grid and the first connection line is smaller than the distance between the first connection line and the first inclined edge, or the first connection line is connected to the second thin grid, and along the second direction, the distance between the end point adjacent to the first connection line of the first thin grid and the first connection line is smaller than the distance between the first connection line and the first inclined edge.

[0022] In some embodiments, along the second direction, the distance between the first connection line and the first inclined edge is greater than the distance between the third connection line and the third inclined edge.

[0023] In some embodiments, the first connection line is connected to the first thin grid, and the third connection line is connected to the second thin grid, along the second direction, the width of the first connection line is smaller than the width of the third connection line. In some embodiments, the width of the second thin grid is greater than the width of the first thin grid. According to a second aspect, the present disclosure further provides a photovoltaic assembly including a solar cell as described above.

Advantages of the Invention

[0024] The beneficial effects of the present disclosure are as follows. The solar cell of the present disclosure includes a silicon wafer and thin grids provided on the silicon wafer (an intermediate layer may be provided between the thin grids and the silicon wafer). The thin grids include first thin grids alternately distributed along a first direction and second thin grids. The silicon wafer has a first edge and a second edge provided opposite to each other along a second direction perpendicular to the first direction, and a third edge and a fourth edge provided opposite to each other along the first direction. A first inclined edge connects the first edge and the third edge. A first connection line is adjacent to the first inclined edge. The first connection line is connected to a first thin grid or a second thin grid. The intersection of the first inclined edge and the first edge is a first intersection point, and the intersection of the first inclined edge and the third edge is a second intersection point. The distance between the first intersection point and the second intersection point is 2.5 millimeters or less. The number of first thin grids or second thin grids connected to the first connection line is 4 or less. By providing as described above, the first inclined edge can be made very small, and further, the first connection line located on the first inclined edge can be shortened so that only 4 or less first thin grids or second thin grids can be connected continuously, ensuring the light receiving area of the cell as much as possible and ensuring the conversion efficiency of the cell.

Brief Description of the Drawings

[0025] [Figure 1] It is a schematic module diagram of a photovoltaic system according to an embodiment of the present disclosure. [Figure 2] It is a schematic module diagram of a battery assembly according to an embodiment of the present disclosure. [Figure 3] It is a schematic plan view of the back surface of a solar cell according to an embodiment of the present disclosure. [Figure 4] It is a schematic local enlargement view of the first conductive contact structure of the solar cell in FIG. 3. [Figure 5] It is another schematic local enlargement view of the first conductive contact structure of the solar cell in FIG. 3. [Figure 6] Figure 3 is another localized, enlarged schematic diagram of the first conductive contact structure of the solar cell. [Figure 7] Figure 3 is yet another localized, enlarged schematic diagram of the first conductive contact structure of the solar cell. [Figure 8] Figure 3 is a localized, magnified schematic diagram of the second conductive contact structure of the solar cell. [Figure 9] Figure 3 is another localized, enlarged schematic diagram of the second conductive contact structure of the solar cell. [Figure 10] Figure 3 is another localized, enlarged schematic diagram of the second conductive contact structure of the solar cell. [Figure 11] Figure 3 is yet another localized magnified schematic of the second conductive contact structure of the solar cell. [Figure 12] This is a schematic diagram of another planar structure of the back surface of a solar cell according to an embodiment of the present disclosure. [Figure 13] This is yet another schematic diagram of the planar structure of the back surface of a solar cell according to an embodiment of the present disclosure. [Figure 14] This is a schematic diagram of the structure of one embodiment of a solar cell according to the present disclosure. [Figure 15] This is an enlarged schematic diagram of section A in Figure 14. [Figure 16] This is an enlarged schematic diagram of section B in Figure 14. [Figure 17] This is a schematic diagram of a structure in which the chamfered edge of one embodiment of the solar cell according to this disclosure is an arc. [Figure 18] This is a schematic diagram of the structure of one embodiment of a solar cell according to this disclosure, in which the chamfered edge is a combination of an arc and a straight line. [Figure 19] This is a schematic diagram showing the structure of a step-like arrangement of connection lines in one embodiment of the solar cell according to this disclosure. [Figure 20] This is a schematic diagram showing the line width between a thin grid and connecting lines in one embodiment of the solar cell according to this disclosure. [Figure 21] This is an enlarged schematic diagram of section C in Figure 14. [Figure 22]This is a schematic diagram of the structure of the first inclined edge of one embodiment of the solar cell according to the present disclosure. [Figure 23] This is a schematic diagram of the structure of the first inclined edge of one embodiment of the solar cell according to the present disclosure. [Modes for carrying out the invention]

[0026] To further clarify the purpose, technical proposal, and advantages of this disclosure, the disclosure will be described in more detail below in conjunction with the drawings and examples. Examples of examples are shown in the drawings, where the same or similar reference numerals from beginning to end represent the same or similar elements, or elements having the same or similar function. The examples described below with reference to the drawings are illustrative and are used solely for the purpose of interpreting this disclosure and should not be understood as limiting this disclosure. It should be understood that the specific embodiments described herein are for the purpose of interpreting this disclosure and are not intended to limit it.

[0027] In the descriptions of this disclosure, the orientations or positional relationships indicated by terms such as “length,” “width,” “top,” “bottom,” “left,” “right,” “horizontal,” “top,” and “bottom” are based on the orientations or positional relationships shown in the drawings and are merely for the purpose of facilitating the explanation of this disclosure and simplifying the description. They do not indicate or imply that the shown devices or elements have a specific orientation, or that they must be configured and operate in a specific orientation, and therefore should not be understood as limitations on this disclosure.

[0028] Furthermore, the terms “first” and “second” are used solely for descriptive purposes and should not be understood as indicating or implying relative importance or implicitly representing the number of technical features described. Thus, features defining “first” and “second” may explicitly or implicitly include one or more features. In this disclosure, “plural” means two or more unless otherwise specified.

[0029] In this disclosure, unless otherwise explicitly stated and limited, the terms “attach,” “connect,” and “connect” should be understood in a broad sense, for example, whether they are fixed connections, detachable connections, or integrated connections; whether they are mechanical connections or electrical connections; whether they communicate with each other, are directly connected, are indirectly connected through an intermediary, or are internal communications or interaction relationships between two elements. A person skilled in the art will be able to understand the specific meaning of these terms in this disclosure depending on the specific circumstances.

[0030] In this disclosure, unless otherwise expressly provided or limited, the presence of a first feature "above" or "below" a second feature may include direct contact between the first and second features, or it may include contact between the first and second features via another feature between them, even if they are not in direct contact. The presence of a first feature "above," "above," and "on the top surface" of a second feature includes the first feature being directly above and diagonally above the second feature, or simply indicates that the horizontal altitude of the first feature is higher than that of the second feature. The presence of a first feature "below," "below," and "on the bottom surface" of a second feature includes the first feature being directly below and diagonally below the second feature, or simply indicates that the horizontal altitude of the first feature is lower than that of the second feature.

[0031] The following disclosure provides many different embodiments or examples to realize the different structures of this disclosure. For the sake of simplicity, the components and arrangements of specific examples are described below. Of course, these are merely examples and are not intended to limit this disclosure. For the sake of simplification and clarity, this disclosure does not show the relationship between the various embodiments and / or settings discussed, but reference numbers and / or reference letters may be repeated in various examples. While this disclosure provides examples of various specific processes and materials, those skilled in the art will be able to recognize the application of other processes and / or the use of other materials.

[0032] The solar cell of this disclosure includes a silicon wafer and a fine grid provided on the silicon wafer (an intermediate layer may be provided between the fine grid and the silicon wafer), wherein the fine grid includes a first fine grid and a second fine grid alternately distributed along a first direction, the silicon wafer has a first edge and a second edge provided opposite to each other along a second direction perpendicular to the first direction, and a third edge and a fourth edge provided opposite to each other along the first direction, the first inclined edge connects the first edge and the third edge, the first connecting line is adjacent to the first inclined edge, the first connecting line is connected to the first fine grid or the second fine grid, the intersection of the first inclined edge and the first edge is the first intersection, the intersection of the first inclined edge and the third edge is the second intersection, the distance between the first intersection and the second intersection is 2.5 millimeters or less, and the number of first fine grids or second fine grids connected to the first connecting line is 4 or less. By arranging it as described above, the first inclined edge can be made very small, and the first connecting line located at the first inclined edge can be made short, so that only four or fewer first thin grids or second thin grids can be connected, thereby maximizing the light-receiving area of ​​the cell and ensuring the conversion efficiency of the cell.

[0033] Example 1 Referring to Figures 1-2, the photovoltaic system 1000 in the embodiments of the present disclosure may include a battery assembly 200 in the embodiments of the present disclosure, which may include several battery strings, and the battery strings may include several busbar-less back-contact solar cells 100 in the embodiments of the present disclosure. In the present disclosure, multiple busbar-less back-contact solar cells 100 in the battery assembly 200 can be formed into battery strings by sequentially connecting welding tapes. Each battery string in the battery assembly 200 can achieve a combined current output after being connected in series, parallel, or series-parallel, and connections between each battery string can be achieved, for example, by busbars.

[0034] Referring to Figure 3, the busbar-less back-contact solar cell 100 in the embodiment of the present disclosure may include a silicon wafer 10, some first fine grids 20, some second fine grids 30, some first conductive contact structures 40, and some second conductive contact structures 50.

[0035] The silicon wafer 10 has opposing front and back surfaces 11, the back surface 11 having some first regions 111 and some second regions 112, some first thin grids 20 and some second thin grids 30 are provided on the back surface 11 of the silicon wafer 10, some first thin grids 20 and some second thin grids 30 are arranged alternately and spaced apart along the first direction, and both the first thin grids 20 and the second thin grids 30 extend along the second direction, the second direction intersects the first direction. Specifically, as shown in Figure 3, the first direction and the second direction may be the longitudinal and transverse directions of the busbar-less back-contact solar cell 100, respectively, and of course, in other embodiments, the first direction and the second direction may be other directions, for example, they may be the diagonal directions of the silicon wafer 10, and are not specifically limited here.

[0036] The first conductive contact structure 40 is located within the first region 111 and is connected to a number of first thin grids 20, while the second thin grid 30 is cut off by the first conductive contact structure 40. The second conductive contact structure 50 is located within the second region 112 and is connected to a number of second thin grids 30, while the first thin grid 20 is cut off by the second conductive contact structure 50.

[0037] In the busbar-less back-contact solar cell 100, battery assembly 200, and photovoltaic system 1000 of the embodiments of the present disclosure, in a first region 111 and a second region 112 on the back surface 11 of a silicon wafer 10, a first conductive contact structure 40 is provided in the first region 111 and connected to a number of first thin grids 20, and a second conductive contact structure 50 is provided in the second region 112 and connected to a number of second thin grids 30, and the first conductive contact structure 40 and the second conductive contact structure 50 may be used to contact the positive and negative electrode probes of a test instrument, respectively. Thus, by providing a small number of first conductive contact structures 40 and a small number of second conductive contact structures 50, the area of ​​the first conductive contact structure 40 and the second conductive contact structure 50 is larger than the area of ​​one first thin grid 20 and one second thin grid 30. When performing tests such as heat spot and EL on a busbar-less back-contact type solar cell 100, the positive and negative electrode probes of the test equipment form stable contact between the first conductive contact structure 40 and the second conductive contact structure 50, reducing the difficulty of the test and increasing the reliability and stability of the test. At the same time, when welding welding tape thereafter, the first conductive contact structure 40 and the second conductive contact structure 50 can function as welding points with the welding tape. Since the first conductive contact structure 40 and the second conductive contact structure 50 are connected to a small number of first thin grids 20 and a small number of second thin grids 30 respectively, it is not necessary to provide welding points or welding layers on all the thin grids during welding, thus reducing the use of welding slurry.

[0038] Specifically, to make it easier to understand, the present disclosure provides that the back surface 11 of the silicon wafer 10 has a small amount of first impurity layer (not shown) and a second impurity layer (not shown), which are a P-type impurity layer and an N-type impurity layer, respectively, and a back surface passivation layer (not shown) is provided on the first and second impurity layers, and a first thin grid 20 is provided above the first impurity layer and penetrates the back surface passivation layer to form ohmic contact with the first impurity layer, and a second thin grid 30 is provided corresponding to the second impurity layer and penetrates the back surface passivation layer to form ohmic contact with the second impurity layer.

[0039] Taking a heat spot test as an example, when performing a heat spot test on the busbar-less back-contact solar cell 100 of this disclosure, the positive electrode probe and negative electrode probe of the test equipment are made to make stable contact with the first conductive contact structure 40 and the second conductive contact structure 50, respectively. Then, a scenario in which the busbar-less back-contact solar cell 100 is shielded is simulated, and the temperature of various parts of the busbar-less back-contact solar cell 100 can be observed.

[0040] In some embodiments, the area of ​​the first region 111 may be 5-60 mm², that is, the orthogonal projection area of ​​the first conductive contact structure 40 onto the back surface 11 may be 5-60 mm².

[0041] In this way, by setting the area of ​​the first region 111 within this reasonable range, it is possible to avoid a situation where the area of ​​the first region 111 is too small, preventing the first conductive contact structure 40 from forming stable contact with the test probe. It is also possible to avoid a situation where the area of ​​the first region 111 is too large, resulting in a relatively small area on the back surface 11 where a thin metal grid cannot be provided, thus affecting the current collection efficiency.

[0042] Specifically, in such embodiments, the area of ​​the first region 111 may be, for example, 5 mm², 10 mm², 15 mm², 20 mm², 25 mm², 30 mm², 35 mm², 40 mm², 45 mm², 50 mm², 55 mm², 60 mm², or any value between 5 mm² and 60 mm², and is not specifically limited herein.

[0043] In some embodiments, the area of ​​the second region 112 may be 5-60 mm², that is, the orthogonal projection area of ​​the second conductive contact structure 50 onto the back surface 11 may be 5-60 mm².

[0044] In this way, by setting the area of ​​the second region 112 within this reasonable range, it is possible to avoid a situation where the area of ​​the second region 112 is too small, preventing the second conductive contact structure 50 from forming stable contact with the test probe, and to avoid a situation where the area of ​​the second region 112 is too large, resulting in a relatively small area on the back surface 11 where a thin metal grid cannot be provided, thus affecting the current collection efficiency.

[0045] Specifically, in such embodiments, the area of ​​the second region 112 may be any value between 5mm², 10mm², 15mm², 20mm², 25mm², 30mm², 35mm², 40mm², 45mm², 50mm², 55mm², and 60mm², and is not specifically limited thereto.

[0046] In some embodiments, the first conductive contact structure 40 and the second conductive contact structure 50 may both be pad points, i.e., welding points for welding to the welding tape.

[0047] In this way, the first conductive contact structure 40 and the second conductive contact structure 50 achieve stable and reliable contact with the test probe, while simultaneously functioning as welding points that come into contact with the weld, thereby reducing the number of welding points during subsequent welding.

[0048] Referring to Figures 3-5, in some embodiments, the first conductive contact structure 40 may include several first conductive connection wires 41 arranged at intervals within the first region 111 along a second direction, the first conductive connection wires 41 intersecting and connecting to several first thin grids 20.

[0049] In this way, the test probe can improve the reliability of the contact by forming a stable electrical contact simply by contacting any of the first conductive connecting wires 41 in the mesh structure within the first region 111.

[0050] In some embodiments, as shown in Figure 5, in such embodiments, some first conductive connecting wires 41 surround some first thin grids 20 and first filling areas 411, or

[0051] As shown in Figure 6, some first conductive connecting wires 41 intersect with some first thin grids 20 to form a first mesh structure 412.

[0052] Thus, the first conductive connection wire 41 forms a first filled region 411 or a first mesh structure 412 with a few first thin grids 20, and during testing, the test probe can improve the reliability of the contact by forming a stable electrical contact by simply making contact with any of the first conductive connection wires 41 in the first region 111 or with any of the first conductive connection wires 41 and the first thin grids 20 in the first mesh structure 412.

[0053] As shown in Figures 6 and 7, in some embodiments, the first conductive contact structure 40 may further include a first conductive material 413 that fills an adjacent first filled area 411 or first mesh structure 412 in order to further improve the contact stability of the test probe. In this way, the area of ​​the first conductive contact structure 40 can be increased, thereby enabling the first conductive contact structure 40 to form a more reliable and stable contact with the test probe during testing, and in such embodiments, the reliability of the welding can be increased when the first conductive contact structure 40 functions as a welding point.

[0054] Of course, in some embodiments, the first conductive contact structure 40 does not need to be filled with the first conductive material 413. If the first conductive contact structure 40 needs to function as a welding point, it can be welded to the welding tape by filling the first filling area 411 or the first mesh structure 412 with a conductive welding material such as solder during subsequent welding.

[0055] Referring to Figures 8 and 9, in some embodiments, the second conductive contact structure 50 includes several second conductive connection wires 51 spaced apart within the second region 112 along the second direction, the second conductive connection wires 51 intersecting and connecting to several second thin grids 30.

[0056] In this way, the test probe can improve the reliability of the contact by forming a stable electrical contact simply by contacting any of the second conductive connecting wires 51 in the mesh structure within the second region 112.

[0057] In some embodiments, as shown in Figure 9, in such embodiments, some second conductive connecting wires 51 surround some second thin grids 30 and second filling areas 511, or

[0058] As shown in Figure 8, some second conductive connecting wires 51 intersect with some second thin grids 30 to form a second mesh structure 512.

[0059] Thus, the second conductive connecting wire 51 forms a second filled region 511 or a second mesh structure 512 with a few second thin grids 30, and during testing, the test probe can improve the reliability of the contact by forming a stable electrical contact by simply making contact with any of the second conductive connecting wires 51 in the second region 112 or with any of the second conductive connecting wires 51 and second thin grids 30 in the second mesh structure 512.

[0060] As shown in Figures 10 and 11, in some embodiments, the second conductive contact structure 50 may further include a second conductive material 513 that fills an adjacent second filled area 511 or second mesh structure 512 in order to further improve the contact stability of the test probe. In this way, the area of ​​the second conductive contact structure 50 can be increased, thereby enabling the second conductive contact structure 50 to form a more reliable and stable contact with the test probe during testing, and in such embodiments, the reliability of the welding can be improved when the second conductive contact structure 50 functions as a welding point.

[0061] Of course, in some embodiments, the second conductive contact structure 50 does not need to be filled with the second conductive material 513. If the second conductive contact structure 50 needs to function as a welding point, it can be welded to the welding tape by filling the second filling area 511 or the second mesh structure 512 with a conductive welding material such as solder during subsequent welding.

[0062] Referring to Figures 3-5, in some embodiments, each first conductive contact structure 40 is connected to correspond to 2-7 first thin grids 20.

[0063] In this manner, the first conductive contact structure 40 can have a relatively large area, and when it functions as a welding point, the number of welding points on the welding tape can be reduced by 2 to 7, thereby reducing the amount of slurry used and improving the reliability of the welding. Furthermore, it is possible to avoid the transmission loss that would occur if there were too many first thin grids 20 connected to the first conductive contact structure 40.

[0064] Specifically, in such embodiments, the number of first thin grids 20 connected to each first conductive contact structure 40 may be, for example, two, three, four, five, six, and seven. For example, as shown in Figure 3, there are seven first thin grids 20 connected to each first conductive contact structure 40.

[0065] Referring to Figures 3, 8, and 9, in some embodiments, each second conductive contact structure 50 is connected to correspond to 2-7 second thin grids 30.

[0066] In this manner, the second conductive contact structure 50 can have a relatively large area, and when it functions as a welding point, the number of welding points on the welding tape can be reduced by 2 to 7, thereby reducing the amount of slurry used and improving the reliability of the welding. Furthermore, it is possible to avoid the transmission loss that would occur if there were too many second thin grids 30 connected to the second conductive contact structure 50.

[0067] Specifically, in such embodiments, the number of second thin grids 30 connected to each second conductive contact structure 50 may be, for example, two, three, four, five, six, and seven. For example, as shown in Figure 3, there are seven second thin grids 30 connected to each second conductive contact structure 50.

[0068] As described above, in some embodiments, both the first conductive contact structure 40 and the second conductive contact structure 50 may be used for welding to a welding point. Specifically, the first conductive contact structure 40 can perform welding tape welding to combine and output the current collected by the first thin grid 20, and the second conductive contact structure 50 can perform welding tape welding to combine and output the current collected by the second thin grid 30.

[0069] In this way, the first conductive contact structure 40 and the second conductive contact structure 50 can form stable contact with the test probe while simultaneously functioning as welding points for the welding tape, thereby achieving functional redundancy.

[0070] Specifically, in such cases, the specific structures of the first conductive contact structure 40 and the second conductive contact structure 50 can be understood by referring to the above.

[0071] Referring to Figure 3, in some embodiments, the silicon wafer 10 has a first edge 101 and a second edge 102 along a first direction, and both the first edge 101 and the second edge 102 have some first conductive contact structure 40 and a second conductive contact structure 50.

[0072] At the first edge 101, some first conductive contact structures 40 and some second conductive contact structures 50 are arranged alternately and spaced apart along the second direction.

[0073] At the second edge 102, some first conductive contact structures 40 and some second conductive contact structures 50 are arranged alternately and spaced apart along the second direction.

[0074] In this way, by providing both the first conductive contact structure 40 and the second conductive contact structure 50 on the edge of the silicon wafer 10, contact with the test probe can be easily facilitated.

[0075] In some embodiments, referring to Figure 3, in such embodiments, a first conductive contact structure 40 located on the first edge 101 is connected to the first thin grid 20 closest to the first edge 101, a second conductive contact structure 50 located on the first edge 101 is connected to the second thin grid 30 closest to the first edge 101, and / or

[0076] The first conductive contact structure 40 located at the second edge 102 is connected to the first thin grid 20 closest to the second edge 102, and the second conductive contact structure 50 located at the second edge 102 is connected to the second thin grid 30 closest to the second edge 102.

[0077] Thus, the first conductive contact structure 40 and the second conductive contact structure 50 are both provided at the outermost ends of the first edge 101 and the second edge 102, respectively. When the first conductive contact structure 40 and the second conductive contact structure 50 function as welding points, they function as the initial and / or final welding points during welding, thereby ensuring welding stability.

[0078] Referring to Figures 3 and 12, in some embodiments, the first conductive contact structure 40 located at the first edge 101 and the first conductive contact structure 40 located at the second edge 102 are aligned in the first direction.

[0079] The second conductive contact structure 50 located at the first edge 101 and the second conductive contact structure 50 located at the second edge 102 are aligned in the first direction.

[0080] Thus, the first conductive contact structure 40 of the first edge 101 is aligned with the first conductive contact structure 40 of the second edge 102, and the second conductive contact structure 50 of the first edge 101 is aligned with the second conductive contact structure 50 of the second edge 102. The two aligned first conductive contact structures 40 can function as the initial and final welding points during welding tape welding to merge the current of the first thin grid 20, respectively, and the two aligned second conductive contact structures 50 can function as the initial and final welding points during welding tape welding to merge the current of the second thin grid 30, respectively. This ensures the reliability of the welding while eliminating the need to set additional initial and final welding points.

[0081] Referring to Figure 12, in some embodiments, between two of the first conductive contact structures 40 aligned in a first direction, there is further at least one of the first conductive contact structures 40 aligned with the first conductive contact structure 40 located at the first edge 101 and the second edge 102, and / or

[0082] Between the two second conductive contact structures 50 aligned in the first direction, there is further at least one second conductive contact structure 50 aligned with the second conductive contact structure 50 located at the first edge 101 and the second edge 102.

[0083] Thus, by providing at least one first conductive contact structure 40 between two first conductive contact structures 40 aligned along opposing directions, and welding the welding point with at least three first conductive contact structures 40 when the first conductive contact structure 40 functions as a welding point, the reliability of the welding can be further ensured. Similarly, by providing at least one second conductive contact structure 50 between two second conductive contact structures 50 aligned along opposing directions, and welding the welding point with at least three second conductive contact structures 50 when the second conductive contact structure 50 functions as a welding point, the reliability of the welding can be further ensured.

[0084] Referring to Figures 3 and 4, in some embodiments, the silicon wafer 10 further has a third edge 103 and a fourth edge 104 facing each other along a second direction, and the third edge 103 is provided with a first edge confluence gate line 60.

[0085] If the conductive contact structure closest to the third edge 103 along the first direction is the first conductive contact structure 40, then the first edge merging gate line 60 is connected to the portion of the second thin grid 30 located at the third edge 103 that is cut by the first conductive contact structure 40 and to at least one second thin grid 30 that is not cut by the first conductive contact structure 40.

[0086] If the conductive contact structure closest to the third edge 103 along the first direction is the second conductive contact structure 50, then the first edge junction gate line 60 connects to the portion of the first thin grid 20 located at the third edge 103 that is cut by the second conductive contact structure 50 and to at least one portion of the first thin grid 20 that is not cut by the first conductive contact structure 40.

[0087] Specifically, if the conductive contact structure closest to the third edge 103 along the first direction is the first conductive contact structure 40, and the first conductive contact structure 40 closest to the third edge 103 functions as a welding point for welding with the welding tape, then the second thin grid 30 needs to be cut by the first conductive contact structure 40. In such a case, the current of the second thin grid 30 located between the first conductive contact structure 40 and the third edge 103 cannot be collected and merged. In this embodiment, by providing a first edge merging gate line 60, the current collected in the second thin grid 30 in this portion is collected in at least one uncut second thin grid 30, thereby enabling the merging of the current in the thin grid in this portion and reducing efficiency losses.

[0088] If the conductive contact structure closest to the third edge 103 along the first direction is the second conductive contact structure 50, and the second conductive contact structure 50 closest to the third edge 103 functions as a welding point for welding with the welding tape, then the first thin grid 20 needs to be cut by the second conductive contact structure 50. In such a case, the current of the portion of the first thin grid 20 located between the second conductive contact structure 50 and the third edge 103 cannot be collected and merged. In this embodiment, by providing a first edge merging gate line 60, the current collected in the first thin grid 20 in this portion can be collected in at least one uncut first thin grid 20, thereby enabling the merging of the current in the thin grid in this portion and reducing efficiency losses.

[0089] Referring to Figures 3 and 8, in some embodiments, a second edge merging gate line 70 is provided at the fourth edge 104.

[0090] If the conductive contact structure closest to the fourth edge 104 in the first direction is the first conductive contact structure 40, then the second edge merging gate line 70 is connected to the portion of the second thin grid 30 located at the fourth edge 104 that is cut by the first conductive contact structure 40 and to at least one second thin grid 30 that is not cut by the first conductive contact structure 40.

[0091] If the conductive contact structure closest to the fourth edge 104 in the first direction is the second conductive contact structure 50, then the second edge merging gate line 70 is connected to the portion of the first thin grid 20 located at the fourth edge 104 that is cut by the second conductive contact structure 50 and to at least one first thin grid 20 that is not cut by the first conductive contact structure 40.

[0092] Specifically, if the conductive contact structure closest to the fourth edge 104 in the first direction is the first conductive contact structure 40, and the first conductive contact structure 40 closest to the fourth edge 104 functions as a welding point for welding with the welding tape, then the second thin grid 30 needs to be cut by the first conductive contact structure 40. In such a case, the current of the second thin grid 30 located between the first conductive contact structure 40 and the fourth edge 104 cannot be collected and merged. In this embodiment, by providing a second edge merging gate line 70, the current collected in the second thin grid 30 in this portion is collected in at least one uncut second thin grid 30, thereby enabling the merging of the current in the thin grid in this portion and reducing efficiency losses.

[0093] If the conductive contact structure closest to the fourth edge 104 in the first direction is the second conductive contact structure 50, and the second conductive contact structure 50 closest to the fourth edge 104 functions as a welding point for welding with the welding tape, then the first thin grid 20 needs to be cut by the second conductive contact structure 50. In such a case, the current of the portion of the first thin grid 20 located between the second conductive contact structure 50 and the fourth edge 104 cannot be collected and merged. In this embodiment, by providing a second edge merging gate line 70, the current collected in this portion of the first thin grid 20 is collected in at least one uncut first thin grid 20, thereby enabling the merging of the current in this portion of the thin grid and reducing efficiency losses.

[0094] Referring to Figure 13, in some embodiments, the silicon wafer 10 has a first centerline L1 and a second centerline L2 that are perpendicular to each other, the first centerline L1 is parallel to the second direction, the second centerline L2 is parallel to the first direction, the silicon wafer 10 is symmetric with respect to the first centerline L1 in the first direction, and the silicon wafer 10 is symmetric with respect to the second centerline L2 in the second direction.

[0095] The first conductive contact structure 40 and the second conductive contact structure 50 are both provided on the first center line L1, and in the first direction, the portions of the first conductive contact structure 40 located on both sides of the first center line L1 are provided symmetrically with respect to the first center line L1, and the portions of the second conductive contact structure 50 located on both sides of the first center line L1 are also provided symmetrically with respect to the first center line L1. Here, the first thin grids 20 on both sides of the first centerline L1 are symmetric with respect to the first centerline L1, and the second thin grids 30 on both sides of the first centerline L1 are also symmetric with respect to the first centerline L1. A first conductive contact structure 40 and a second conductive contact structure 50 are provided on both sides of the second center line L2. The first conductive contact structures 40 located on both sides of the second center line L2 are provided symmetrically with respect to the second center line L2, and the second conductive contact structures 50 located on both sides of the second center line L2 are also provided symmetrically with respect to the second center line L2.

[0096] In this way, rotational symmetry can be achieved between the first conductive contact structure 40 and the second conductive contact structure 50. Thus, in the manufacturing process, after printing the first conductive contact structure 40, the first thin grid 20 and the second thin grid 30 are provided, allowing the busbar-less back-contact type solar cell 100 to be freely moved and replaced without the need for alignment and calibration.

[0097] Specifically, as shown in Figure 13, in this embodiment, the same number of first conductive contact structures 40 (for example, one, two, or three) are provided on both sides of the second center line L2, and the first conductive contact structures 40 on both sides are symmetrical with respect to the second center line L2. The same number of second conductive contact structures 50 are also provided, and the second conductive contact structures 50 on both sides are also symmetrical with respect to the second center line L2. At the same time, the center point of each conductive contact structure is located on the first center line L1, and the portions of each conductive contact structure located on both sides of the first center line L1 are symmetrical with respect to the first center line L1.

[0098] In some embodiments, it is not necessary to provide another thin grid on the first centerline L1. Of course, in order to make the most of the area of ​​the silicon wafer 10, a central thin grid 80 may be provided on the first centerline L1, and the central thin grid 80 has the same polarity as the thin grids (first thin grid 20 or second thin grid 30, shown in Figure 13) on the thin grids (first thin grid 20 or second thin grid 30, second thin grid 30 shown) on both opposing edges (i.e., first edge 101 and second edge 102) along the first direction that are closest to the silicon wafer 10.

[0099] Thus, by providing a central thin grid 80 with the same polarity as the thin grid closest to the first edge 101 and the second edge 102, all thin grids on both sides of the central gate line can be made symmetrical with respect to the central thin grid 80, thereby achieving the objective of allowing movement and exchange during the thin grid provisioning process. As can be easily understood, in such embodiments, an impurity layer corresponding to its polarity can be provided below the central thin grid 80, and the central thin grid 80 penetrates the passivation layer and comes into contact with the impurity layer below, thereby increasing area utilization and enhancing current collection capability.

[0100] Specifically, as shown in Figure 13, if the thin grids closest to the first edge 101 and the second edge 102 are both the second thin line 30, then the central thin grid 80 is the same gate line as the second thin grid 30. This corresponds to the first thin grid 20 and the second thin grid 30 being arranged alternately at equal intervals on the silicon wafer 10, and the thin grids located at both the upper and lower edges in the first direction being the second thin grid 30, with N second thin grids 30 and N-1 first thin grids 20, and the increased number of second gate lines 30 coinciding with the first center line L1 being the central thin grid 80. Similarly, if the thin grids closest to the first edge 101 and the second edge 102 are both the first thin line 20, then the central thin grid 80 is the same thin grid as the first thin grid 20 in terms of polarity, which will not be explained in detail here.

[0101] Continuing with reference to Figure 13, in such an embodiment, the first conductive contact structure 40 may include a first Pad point 401 located on a first centerline L1 and two first connecting lines 402 connected to both ends of the first Pad point and extending in a first direction, the first connecting lines 402 being connected to at least one first thin grid 20, and the second conductive contact structure 50 may include a second Pad point 501 located on the first centerline L1 and two second connecting lines 502 connected to both ends of the second Pad point 501 and extending in a first direction, the second connecting lines 502 being connected to at least one second thin grid 30.

[0102] By using pad points to ensure stable contact with the probe, and then connecting a thin portion of the grid with connecting wires, it is possible to perform stable testing of electrical performance and heat spots.

[0103] In some embodiments, the width of the first connecting line 402 may be greater than the width of the first thin grid 20, and the width of the second connecting line 502 may be greater than the width of the second thin grid 30, and the width of the first connecting line 402 and the second connecting line 502 is the length of the second side of both, and the width of the first thin grid 20 and the second thin grid 30 is the length of the first side of both.

[0104] Example 2 As shown in Figures 14 to 23, one embodiment of the present disclosure provides a solar cell.

[0105] A silicon wafer 100 having a few fine grids, the silicon wafer 100 includes a first fine grid 200 and a second fine grid 300 that are alternately distributed along a first direction.

[0106] Silicon wafer 100 is A first edge 111 and a second edge 112 are provided opposite to each other along a second direction perpendicular to the first direction, and a third edge 113 and a fourth edge 114 are provided opposite to each other along the first direction, A first inclined edge 121 connects the first edge 111 and the third edge 113, A first connecting line 410 provided adjacent to the first inclined edge 121, having a first connecting line 410 connected to at least one first thin grid 200 or at least one second thin grid 300, The intersection of the first inclined edge 121 and the first edge 111 is the first intersection J2, the intersection of the first inclined edge 121 and the third edge 113 is the second intersection J1, the distance between the first intersection J2 and the second intersection J1 is 2.5 millimeters or less, and the number of first thin grids 200 or second thin grids 300 connected to the first connecting line 410 is 4 or less.

[0107] During implementation, the silicon wafer 100, the first thin grid 200, and the second thin grid 300 may refer to the silicon wafer 10, the first thin grid 20, and the second thin grid 30 in the above example 1, respectively. The silicon wafer 100 is, in other words, a silicon substrate, and the silicon substrate may be an N-type silicon wafer or a P-type silicon wafer. Here, an N-type silicon wafer is obtained by adding a pentavalent element (e.g., valine, arsenic, or bismuth) to intrinsic semiconductor silicon, and a P-type silicon wafer is obtained by adding a trivalent element (e.g., boron, gallium, or indium) to intrinsic semiconductor silicon. Further explanation is omitted.

[0108] The silicon wafer 100 has a front and a back surface, where the front surface of the silicon wafer 100 corresponds to the light-receiving surface of the solar cell, and similarly, the back surface of the silicon wafer 100 corresponds to the backlight surface of the solar cell.

[0109] In some embodiments, the thin grid may be provided on the front or back surface of the silicon wafer 100, where the thin grid is a metallic thin grid and includes a first thin grid 200 and a second thin grid 300, which are distributed alternately along the first direction. Exemplarily, if the first direction is the longitudinal direction, the first thin grid 200 and the second thin grid 300 are sequentially distributed alternately from top to bottom on the silicon wafer 100, with one second thin grid 300 between two adjacent first thin grids 200, and similarly, one first thin grid 200 between two adjacent second thin grids 300, and so on, which are omitted from further explanation.

[0110] The silicon wafer 100 has four edges in a sheet-like or plate-like shape, a third edge 113 and a fourth edge 114 that are opposite each other along the first direction, and a first edge 111 and a second edge 112 that are opposite each other along the second direction, with the second direction being perpendicular to the first direction.

[0111] For example, if the first direction is the vertical direction, the second direction is the horizontal direction, in which case the first edge 111 and the second edge 112 can be considered as the left edge and the right edge of the silicon wafer 100, and similarly, the third edge 113 and the fourth edge 114 can be considered as the top edge and the bottom edge of the silicon wafer 100. In some other embodiments, if the first direction is the horizontal direction, the second direction is the vertical direction, in which case the first edge 111 and the second edge 112 can be considered as the top edge and the bottom edge of the silicon wafer 100, and similarly, the third edge 113 and the fourth edge 114 can be considered as the left edge and the right edge of the silicon wafer 100, and further explanation is omitted.

[0112] The silicon wafer 100 is provided with a first inclined edge 121 connected to a first edge 111 and a third edge 113, and a first connecting line 410 is provided adjacent to the first inclined edge 121, and the first connecting line 410 can be connected to a first thin grid 200 or a second thin grid 300, and at the same time the distance between the first intersection J2 and the second intersection J1 is less than 2.5 millimeters, that is, by designing the first inclined edge 121 to be a relatively small chamfered area, the number of first thin grids 200 or second thin grids 300 to which the first connecting line 410 can be connected is limited to four or less. For illustrative purposes, taking as an example that the first connecting line 410 is connected to the first thin grid 200, the first connecting line 410 may connect four first thin grids 200, or three first thin grids 200, or two first thin grids 200, or one first thin grid 200.

[0113] Selectively, the distance between the first intersection J2 and the second intersection J1 is 2.5 millimeters or less. For example, the distance between the first intersection J2 and the second intersection J1 can be designed to be any of the following values: 0.9 millimeters, 1.1 millimeters, 1.2 millimeters, 1.5 millimeters, 1.6 millimeters, 1.8 millimeters, 2.0 millimeters, 2.4 millimeters, or between 0.7 millimeters and 2.5 millimeters. Preferably, the distance between the first intersection J2 and the second intersection J1 is between 1.2 millimeters and 1.6 millimeters. For example, the preset threshold is any of the following values: 1.3 millimeters, 1.4 millimeters, 1.45 millimeters, 1.5 millimeters, or between 1.2 millimeters and 1.6 millimeters, but is not limited to these.

[0114] In some possible embodiments, the silicon wafer 100 includes a second beveled edge 122, a third beveled edge 123, and a fourth beveled edge 124, where the second beveled edge 122 connects the first edge 111 to the fourth edge 114, the third beveled edge 123 connects the second edge 112 to the third edge 113, and the fourth beveled edge 124 connects the second edge 112 to the fourth edge 114.

[0115] The silicon wafer 100 is further provided with a second connection line 420, a third connection line 430, and a fourth connection line 440, where the second connection line 420 is adjacent to the second inclined edge 122, the third connection line 430 is adjacent to the third inclined edge 123, and the fourth connection line 440 is adjacent to the fourth inclined edge 124. The second connection line 420, the third connection line 430, and the fourth connection line 440 are all connected to at least one first thin grid or at least one second thin grid.

[0116] During implementation, the first connection line 410 and the second connection line 420 are connected to thin grids having the same polarity, and the first connection line 410 and the third connection line 430 are connected to thin grids having opposite polarity. For example, if the first connection line 410 is connected to the first thin grid 200, the second connection line 420 is similarly connected to the first thin grid 200, the third connection line 430 is connected to the second thin grid 300, and the fourth connection line 430 is similarly connected to the second thin grid 300.

[0117] The fact that the intersection points of the first inclined edge 121 and the corresponding edge are J1 and J2 is illustrative in the embodiment of this disclosure, but not a specific limitation to this disclosure. In some other embodiments, the second inclined edge 122, the third inclined edge 123, and the fourth inclined edge 124 can be described by referring to the first inclined edge 121, and their description is omitted.

[0118] In some possible embodiments, taking as an example that the first connection line 410 is connected to the first thin grid 200, the first connection line 410 may connect two first thin grids 200, the third connection line 430 is connected to one second thin grid 300, the second connection line 420 is connected to two first thin grids 200, and the fourth connection line 440 is connected to one second thin grid 300.

[0119] Selectively, the first connection line 410 may connect three first thin grids 200, the third connection line 430 may connect two second thin grids 300, the second connection line 420 may connect three first thin grids 200, and the fourth connection line 440 may connect two second thin grids 300. Selectively, the first connection line 410 may connect four first thin grids 200, the third connection line 430 may connect three second thin grids 300, the second connection line 420 may connect four first thin grids 200, and the fourth connection line 440 may connect three second thin grids 300.

[0120] The number of thin grids connected to the connecting lines of each of the above-described inclined edges is an illustrative description of one embodiment of the present disclosure, but is not a specific limitation to the present disclosure. In some other embodiments, the number of thin grids connected to the connecting lines of each inclined edge can be set as needed and is not limited.

[0121] The solar cell of this disclosure includes a silicon wafer 100 and a fine grid provided on the silicon wafer 100, the fine grid including a first fine grid 200 and a second fine grid 300 that are alternately distributed along a first direction, the silicon wafer 100 having a first edge 111 and a second edge 112 that are opposite to each other along a second direction perpendicular to the first direction, a third edge 113 and a fourth edge 114 that are opposite to each other along the first direction, a first inclined edge 121 that connects the first edge 111 and the third edge 113, and a first inclined edge A first connecting line 410 is provided adjacent to 121 and has a first connecting line 410 that is connected to at least one first thin grid 200 or at least one second thin grid 300, the intersection point of the first inclined edge 121 and the first edge 111 is the first intersection point J2, the intersection point of the first inclined edge 121 and the third edge 113 is the second intersection point J1, the distance between the first intersection point J2 and the second intersection point J1 is 2.5 millimeters or less, and the number of first thin grids 200 or second thin grids 300 connected to the first connecting line 410 is 4 or less. By providing it as described above, the first inclined edge 121 can be made very small, and the first connecting line 410 located on the first inclined edge 121 can be made even shorter, so that only 4 or fewer first thin grids 200 or second thin grids 300 can be connected, the light-receiving area of ​​the cell can be secured as much as possible, and the conversion efficiency of the cell can be secured.

[0122] In some selective embodiments, the first inclined edge 121 is a straight line or an arc.

[0123] During implementation, each inclined edge can be a straight line, as shown in Figures 14, 15, and 16, with the first inclined edge 121 as an example. In some possible embodiments, each inclined edge may be an arc, as shown in Figure 17, with the first inclined edge 121 as an example. Of course, each inclined edge can be a combination of a straight line and an arc, as shown in Figure 18.

[0124] In some selective embodiments, the connecting lines are not parallel to the corresponding beveled edges. For example, the first connecting line 410 is not parallel to the first beveled edge 121, the second connecting line 420 is not parallel to the second beveled edge 122, the third connecting line 430 is not parallel to the third beveled edge 123, and the fourth connecting line 440 is not parallel to the fourth beveled edge 124, as shown in Figure 21 (details omitted).

[0125] In some selective embodiments, the first connecting wire 410 includes a first connector 450 and a second connector 460, the first connector 450 being used to connect two thin grids of the same polarity, and the second connector 460 being connected to the first connector 450.

[0126] The entire network of connection lines can be designed in a stepped manner, and as shown in Figure 19, exemplary, the silicon wafer 100 has the first first thin grid 200, the first second thin grid 300, the second first thin grid 200, the second second thin grid 300, ..., the Nth first thin grid 200 and the Nth second thin grid 300 distributed sequentially from top to bottom. The first end of the first connection portion 450 of the first connection line 410 is connected to the first first thin grid 200, the second end of the first connection portion 450 of the first connection line 410 is connected to the second first thin grid 200, and the second connection portion 460 of the first connection line 410 is perpendicular or nearly perpendicular to the first connection portion 450 of the first connection line 410. Similarly, the first end of the first connector 450 of the second connector 420 is connected to the first second thin grid 300, the second end of the first connector 450 of the second connector 420 is connected to the second second thin grid 300, and the second connector 460 of the second connector 420 is perpendicular or nearly perpendicular to the first connector 450 of the second connector 420.

[0127] During implementation, the second connection 460 and the first connection 450 are connected by a single thin grid, and selectively, the second connection 460 and the first connection 450 are parallel to the first direction, and selectively, the first connection 450 is diagonal. The first connection part 450 and the second connection part 460 are distributed along the flow of current; that is, the first end of the first connection part 450 is connected to the first thin grid 200, and the second end of the first connection part 450 is connected to the second thin grid 200, at which point the current of the first thin grid 200 flows through the first connection part 450. The second connection part 460 is connected to the first connection part 450, at which point the sum of the currents of the first and second thin grids 200 flows through the second connection part 460. By making the width of the first connection part 450 smaller than the width of the second connection part 460, the wiring resistance (resistance) of the second connection part 460 is effectively reduced, thereby reducing the overall electrical energy loss of the connection line and improving the power generation efficiency of the solar cell.

[0128] In some selective embodiments, the width of the connecting wire 400 is greater than the width of the narrow grid. In practice, the width of the connecting wire 400 relates to the wiring resistance, and generally, the wider the wire, the lower the wiring resistance, and the wiring resistance loss of connecting wires of different widths differs. For example, if the width of the connecting wire 400 is 150 μm, the wiring resistance loss is 0.0095 W. If the width of the connecting wire 400 is 300 μm, the wiring resistance loss is 0.0048 W. If the width of the connecting wire 400 changes gradually, for example, if the width of the connecting wire 400 changes gradually from 150 μm to 300 μm, the wiring resistance loss is 0.0062 W. Therefore, as shown in Figure 20, by employing a connecting wire 400 with a relatively large width, the wiring resistance of the connecting wire 400 can be effectively reduced, thereby reducing the loss when current flows through the connecting wire 400.

[0129] By selectively designing the width of the connecting wire 400 to be wider, the wiring resistance of the connecting wire 400 can be effectively reduced. However, if the width of the connecting wire 400 is increased, it obstructs the light-receiving area of ​​the solar cell, thereby reducing the power generation efficiency of the solar cell. In this case, the ratio of the width of the narrow grid to the width of the connecting wire 400 can be designed from 1:1.2 to 1:2. For example, the ratio of the width of the narrow grid to the width of the connecting wire 400 can be designed to be 1:1:3, 1:1.5, or 1:1.9, and preferably, the ratio of the width of the narrow grid to the width of the connecting wire 400 is 1:1.6-1:1.8. For example, the ratio of the width of the narrow grid to the width of the connecting wire 400 can be designed to be 1:1:7, or 1:1.75, and is not limited to these. By providing the above configuration, it is possible to effectively balance the wiring resistance of the connecting wire 400 with the power generation efficiency of the solar cell.

[0130] In some selective embodiments, the angle between the first connecting line 410 and the second direction is greater than the angle between the third connecting line 420 and the second direction, and similarly, the angle between the second connecting line 420 and the second direction is greater than the angle between the fourth connecting line 440 and the second direction.

[0131] During implementation, the second direction is the direction parallel to the thin grid. For example, if the first thin grid 200 and the second thin grid 300 are arranged alternately in the vertical direction, the second direction is the horizontal direction, meaning that the first thin grid 200 and the second thin grid 300 extend horizontally. For example, if the angle between the first connecting line 410 and the second direction is Z1, and the angle between the third connecting line 430 and the second direction is Z2, then Z1 > Z2. Similarly, if the angle between the second connecting line 420 and the second direction is Z3, and the angle between the fourth connecting line 440 and the second direction is Z4, then Z3 > Z4.

[0132] In some selective embodiments, the first connection line 410 and the second connection line 420 are both used to connect to the first narrow grid 200, and the third connection line 430 and the fourth connection line 440 are both used to connect to the second narrow grid 300.

[0133] If the first connecting line 410 is connected to the first thin grid 200 along the second direction, the distance between the first connecting line 410 and the endpoint of the second thin grid 300 adjacent to the first connecting line 410 is smaller than the distance between the first connecting line 410 and the first inclined edge 121, or if the first connecting line 410 is connected to the second thin grid 300, the distance between the first connecting line 410 and the endpoint of the first thin grid 200 adjacent to the first connecting line 410 is smaller than the distance between the first connecting line 410 and the first inclined edge 121.

[0134] As an example, selectively, the first connecting line 410 is connected to the first thin grid 200, as shown in Figure 22. In this case, the first connecting line 410 and the second thin grid 300 are spaced apart, and the distance between the first connecting line 410 and the end of the second thin grid 300 is considered to be D1, and the distance between the first connecting line 410 and the first inclined edge 121 is considered to be D2. <D2である。

[0135] In some possible embodiments, when the connecting line is spaced apart from multiple thin grids, as shown in Figure 23, the first thin grid 200, the first second thin grid 300, the second first thin grid 200, and the second second thin grid 300 are distributed sequentially from top to bottom. The first connecting line 410 is connected to the first thin grid 200 and the second first thin grid 200. When the first connecting line 410, the first second thin grid 300, and the second second thin grid 300 are all spaced apart, the thin grid closest to the connecting line is selected to check the distance. For example, if the distance between the first connecting line 410 and the end of the first second thin grid 300 is less than the distance between the first connecting line 410 and the end of the second second thin grid 300, and the distance between the first connecting line 410 and the end of the first second thin grid 300 is considered to be D1, and the distance between the first connecting line 410 and the first inclined edge 121 is considered to be D2, then D1 <D2である。

[0136] Similarly, in some other embodiments, the second connection line 420, the third connection line 430, and the fourth connection line 440 may refer to the design of the first connection line 410 described above, and their explanation will be omitted.

[0137] In some selective embodiments, along the second direction, the distance between the first connecting line 410 and the first inclined edge 121 is greater than the distance between the third connecting line 430 and the third inclined edge 123.

[0138] If the second direction is the lateral direction, the first inclined edge 121 is located at the upper left corner of the silicon wafer 100, the second inclined edge 122 is located at the lower left corner of the silicon wafer 100, the third inclined edge 123 is located at the upper right corner of the silicon wafer 100, and the fourth inclined edge 124 is located at the lower right corner of the silicon wafer 100. The distance between the first connection line 410 and the edge of the first inclined edge 121 is greater than the distance between the third connection line 430 and the edge of the third inclined edge 123, and similarly, the distance between the second connection line 420 and the edge of the second inclined edge 122 is greater than the distance between the fourth connection line 440 and the edge of the fourth inclined edge 124.

[0139] Selectively, the connecting lines are not parallel to the corresponding inclined edges. For example, the first connecting line 410 is not parallel to the first inclined edge 121, and similarly, the second connecting line 420 is not parallel to the second inclined edge 122, and so are the third and fourth connecting lines 430 and 440, which will not be explained further. The point of the inclined edge closest to the connecting line can be selected to determine the distance. Taking the first connecting line 410 as an example, if the distance between the upper end of the first connecting line 410 and the first inclined edge 121 is greater than the distance between the lower end of the first connecting line 410 and the first inclined edge 121, then the distance between the lower end of the first connecting line 410 and the first inclined edge 121 is considered the distance between the first connecting line 410 and the first inclined edge 121. Of course, the average of the distances between both ends of the first connecting line 410 and the first inclined edge 121 can be selected as the distance between the first connecting line 410 and the first inclined edge 121, which will not be explained further.

[0140] In some selective embodiments, a first connecting line 410 is connected to a first thin grid 200, a third connecting line 430 is connected to a second thin grid 300, and along the second direction, the width of the first connecting line 410 is smaller than the width of the third connecting line 430; similarly, a second connecting line 420 is connected to the first thin grid 200, and a fourth connecting line 440 is connected to a second thin grid 300, and along the second direction, the width of the second connecting line 420 is smaller than the width of the fourth connecting line 440.

[0141] In some selective embodiments, the width of the second thin grid 300 is greater than the width of the first thin grid 200.

[0142] In some selective embodiments, if the first direction is the vertical direction, the second direction is the horizontal direction, and the second thin grid 300 and the first thin grid 200 are distributed alternately along the first direction and provided on the silicon wafer 100 so that the first thin grid 200 and the second thin grid 300 are distributed symmetrically vertically. For example, if the first thin grid 200 is closest to the third edge 113, then the first thin grid is also closest to the fourth edge 114. Furthermore, the first thin grid 200 and the second thin grid 300 are asymmetrical horizontally.

[0143] Example 2 In some selective embodiments, the present disclosure provides a photovoltaic assembly including a solar cell as described above.

[0144] The photovoltaic assembly consists of at least one solar cell, in which a first thin grid 200 in the solar cell is connected by a positive electrode welding tape 500, and a second thin grid 300 is connected by a negative electrode welding tape 600. The welding tapes of adjacent solar cells can be connected in series or parallel, and further details are omitted.

[0145] As will be readily apparent to those skilled in the art, for the convenience and brevity of description, the structure and implementation principle of the photovoltaic assembly described above may refer to the corresponding structure and implementation principle of Embodiment 1, and will not be explained further here.

[0146] The solar cell of this disclosure includes a silicon wafer 100 and a fine grid provided on the silicon wafer 100, the fine grid including a first fine grid 200 and a second fine grid 300 that are alternately distributed along a first direction, the silicon wafer 100 having a first edge 111 and a second edge 112 that are opposite to each other along a second direction perpendicular to the first direction, a third edge 113 and a fourth edge 114 that are opposite to each other along the first direction, a first inclined edge 121 that connects the first edge 111 and the third edge 113, and a first inclined edge A first connecting line 410 is provided adjacent to 121 and has a first connecting line 410 that is connected to at least one first thin grid 200 or at least one second thin grid 300, the intersection point of the first inclined edge 121 and the first edge 111 is the first intersection point J2, the intersection point of the first inclined edge 121 and the third edge 113 is the second intersection point J1, the distance between the first intersection point J2 and the second intersection point J1 is 2.5 millimeters or less, and the number of first thin grids 200 or second thin grids 300 connected to the first connecting line 410 is 4 or less. By providing it as described above, the first inclined edge 121 can be made very small, the first connecting line 410 located on the first inclined edge 121 can be made even shorter, and only 4 or fewer first thin grids 200 or second thin grids 300 can be connected, thereby securing as much light-receiving area as possible of the cell and ensuring the conversion efficiency of the cell.

[0147] The foregoing are merely preferred embodiments of the Disclosure and are not intended to limit the Disclosure. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the Disclosure should be included within the scope of the Disclosure's protection.

Claims

1. It is a solar cell, The present invention includes a silicon wafer, the silicon wafer having a number of fine grids, the fine grids comprising a first fine grid and a second fine grid that are alternately distributed along a first direction, The aforementioned silicon wafer is A first edge and a second edge are provided opposite to each other along a second direction perpendicular to the first direction, and a third edge and a fourth edge are provided opposite to each other along the first direction, A first inclined edge connecting the first edge and the third edge, A first connecting line provided adjacent to the first inclined edge, having a first connecting line connected to at least one of the first thin grids or at least one of the second thin grids, A solar cell in which the intersection point of the first inclined edge and the first edge is the first intersection point, the intersection point of the first inclined edge and the third edge is the second intersection point, the distance between the first intersection point and the second intersection point is 2.5 millimeters or less, and the number of the first thin grid or the second thin grid connected to the first connecting line is 4 or less.

2. The solar cell according to claim 1, wherein the first inclined edge is a straight line or an arc.

3. The solar cell according to claim 2, wherein the first connection line is not parallel to the first inclined edge.

4. The solar cell according to any one of claims 1 to 2, wherein the first connecting line includes a first connecting portion and a second connecting portion, and the width of the first connecting portion is smaller than the width of the second connecting portion.

5. The solar cell according to claim 4, wherein the first connection portion is connected to the second connection portion, and the first connection portion is shaded.

6. The solar cell according to claim 4, wherein the second connection portion and the first connection portion are connected by a single thin grid.

7. The solar cell according to claim 6, wherein the second connection portion and the first connection portion are parallel to the first direction.

8. The solar cell according to claim 4, wherein the ratio of the width of the thin grid to the width of the first connecting line is 1:1.2 to 1:

2.

9. The solar cell according to claim 8, wherein the ratio of the width of the thin grid to the width of the first connecting line is 1:1.6 to 1:1.

8.

10. The solar cell according to claim 1, wherein the distance between the first intersection and the second intersection is 0.7 millimeters to 2.5 millimeters.

11. The solar cell according to claim 10, wherein the distance between the first intersection and the second intersection is 1.2 millimeters to 1.6 millimeters.

12. The silicon wafer includes a second inclined edge connecting the first edge and the fourth edge. The silicon wafer is provided with a second connection line adjacent to the second inclined edge, and the second connection line is connected to at least one of the first thin grids or at least one of the second thin grids. The solar cell according to claim 1, wherein the first connection line and the second connection line are connected to a thin grid having the same polarity.

13. The silicon wafer includes a third inclined edge connecting the second edge and the third edge, The silicon wafer is provided with a third connection line adjacent to the third inclined edge, and the third connection line is connected to at least one of the first thin grids or at least one of the second thin grids. The solar cell according to claim 12, wherein the first connection line and the third connection line are connected to a thin grid having opposite polarity.

14. The solar cell according to claim 13, wherein the angle between the first connecting line and the second direction is greater than the angle between the third connecting line and the second direction.

15. The first connecting line is connected to a first thin grid, and along the second direction, the distance between the first connecting line and an endpoint of the second thin grid adjacent to the first connecting line is less than the distance between the first connecting line and the first inclined edge, or The solar cell according to claim 1, wherein the first connection line is connected to a second thin grid, and the distance between the first connection line and an endpoint of the first thin grid adjacent to the first connection line along the second direction is less than the distance between the first connection line and the first inclined edge.

16. The solar cell according to claim 13, wherein, along the second direction, the distance between the first connection line and the first inclined edge is greater than the distance between the third connection line and the third inclined edge.

17. The first connecting wire is connected to the first thin grid, and the third connecting wire is connected to the second thin grid. The solar cell according to claim 13, wherein, along the second direction, the width of the first connecting line is smaller than the width of the third connecting line.

18. The solar cell according to claim 1, wherein the width of the second narrow grid is greater than the width of the first narrow grid.

19. A photovoltaic assembly comprising a solar cell according to any one of claims 1 to 18.

Images