Solar cells and solar modules

Abstract

This application discloses a solar cell and a solar module, which relate to the photovoltaic technical field and reduce the risk of cracking of the solar cell. The solar cell includes a cell body, a current collecting electrode, and a first interconnect structure. At least some regions of different first interconnect structures distributed at intervals in a second direction are located on the same connection line. The number of connection lines located within the same target surface is N1, and the number of first interconnect structures intersecting with target line segments located within the target surface is N2, where N2 < (1 / 2)N1. The target line segments are line segments connecting the midpoint of the longer of two edges extending in the first direction of the target surface and distributed opposite to each other to the apex end point of the shorter of the two edges. Alternatively, the number of connection lines intersecting with a vector line segment with a 45° inclination angle is N3, and the number of first interconnect structures intersecting with at least one identical vector line segment with a 45° inclination angle is N4, where N3 > N4.

Description

[Technical Field]

[0001] The present application relates to the technical field of photovoltaics, and in particular to solar cells and solar modules.

[0002] (CROSS-REFERENCE TO RELATED APPLICATIONS) This application claims priority from a Chinese patent application entitled "Solar Cell and Solar Module," application number 202410517763.7, filed with the China Patent Office on April 28, 2024, the entire contents of which are incorporated herein by reference. [Background technology]

[0003] Currently, solar cells are increasingly being used as a new alternative energy source. Among them, photovoltaic solar cells are devices that convert light energy from the sun into electrical energy. Specifically, solar cells use the principle of photovoltaic power to generate carriers, and then use electrodes to extract the carriers, which is advantageous for the effective use of electrical energy.

[0004] However, in conventional solar cells, the distribution position of the interconnection structure in the cell body is irrational, resulting in large interconnection stress after interconnecting adjacent solar cells, which significantly increases the risk of cracking and reduces the structural reliability of the solar module. Summary of the Invention

[0005] The objective of the present application is to provide a solar cell and a solar module for reducing interconnection stress formed after interconnecting adjacent solar cells, thereby reducing the risk of cracking of the solar cells and improving the structural reliability of the solar module.

[0006] To achieve the above object, in a first aspect, the present application provides a solar cell including a cell body, a current collecting electrode, and a first interconnect structure. The cell body has opposing first and second surfaces. At least one of the first and second surfaces is a target surface. The current collecting electrode is provided on the target surface. Different current collecting electrodes located on the same target surface all extend in a first direction and are spaced apart in a second direction. The first direction is perpendicular to the second direction. The first interconnect structure is formed in an array on the target surface. Each first interconnect structure is electrically connected to at least one current collecting electrode. At least some regions of different first interconnect structures spaced apart in the second direction are located on the same connection line, and the different connection lines are spaced apart in the first direction. Here, the number of connection lines located within the same target surface is N1, the number of first interconnect structures intersecting with target line segments located within the target surface is N2, where N2<(1 / 2)N1, and the target line segments are line segments connecting the midpoint of the longer of two edges extending in a first direction of the target surface and distributed opposite to each other to the apex end point of the shorter of the two edges. Alternatively, the number of connection lines intersecting with vector line segments with a 45° inclination angle is N3, and the number of first interconnect structures intersecting with at least one same 45° inclination vector line segment is N4, where N3>N4.

[0007] When the above technical solution is adopted, the solar cell provided in the present application includes first interconnection structures provided on the target surface of the cell body, and the first interconnection structures are arrayed on the target surface. Each first interconnection structure is electrically connected to at least one collecting electrode. Furthermore, at least some regions of different first interconnection structures distributed at intervals in the second direction are located on the same connecting line, and the different connecting lines are distributed at intervals in the first direction. In this case, when adjacent solar cells are interconnected in the extension direction of the connecting line using intra-string interconnection members such as solder ribbons, the intra-string interconnection members corresponding to the connecting line in a one-to-one correspondence are electrically connected to collecting electrodes of the same polarity located on the target surface via at least the first interconnection structures, and carriers collected by the collecting electrodes can be sequentially guided through the first interconnection structures and the intra-string interconnection members to form photocurrent. After adjacent solar cells are interconnected, interconnection stress occurs after interconnection due to differences in the materials and thermal expansion coefficients of the first interconnection structures and the cell body. Based on this, the target line segment contacts at most half of all the connecting lines located on the same target surface. Also, when N2<(1 / 2)N1, it can be ensured that none of the first interconnect structures electrically contacting at least one connecting line on the target surface that can intersect with the target line segment are provided on the target line segment, so that after adjacent solar cells are interconnected in the extension direction of the connecting lines by the intra-string interconnect members, none of the corresponding first interconnect structures electrically contacting at least one intra-string interconnect member will generate interconnection stress on the target line segment, and the interconnection stress formed in the extension direction of the target line segment will be reduced. In this case, the direction of the diagonal line within the surface of the semiconductor wafer used in manufacturing solar cells is approximately parallel to the cleavage plane, which is a plane that has the property of allowing mineral crystals to be ruptured in a strictly fixed crystallization direction by an external force and break into a smooth surface. Therefore, when a single-crystal silicon rod is wire-cut to correspond to a silicon wafer, an approximately rectangular silicon wafer is formed, and the cleavage plane intersects with the surface of the silicon wafer and is not parallel to the edge of the silicon wafer.The crystal bar contains numerous parallel cleavage planes, forming numerous target segments parallel to the silicon wafer surface. Among these, the target segments corresponding to the diagonals of the silicon wafer are the longest and experience the greatest stress. However, the positions of the target segments before and after the silicon wafer is cut in half remain unchanged. Therefore, when a target segment is defined as a line segment connecting the midpoint of the longer of two edges (e.g., the non-chamfered edge) that extend in a first direction across the target surface and the apex end point of the shorter of the two edges (e.g., the chamfered edge), the extension direction of the target segment is approximately parallel to the direction of the cleavage planes of the cell body. In this case, the reduction in interconnect stress along the extension direction of the target segments corresponds to the reduction in interconnect stress along the cleavage planes. This reduces the risk of cracking of solar cells after external forces due to high interconnect stress, thereby improving the structural reliability of solar modules fabricated based on the solar cells. Next, if the number N3 of connection lines corresponding to a vector segment with a 45° inclination angle is greater than the number N4 of first interconnect structures intersecting with the connection lines, none of the first interconnect structures on at least one connection line is located on the vector segment with a 45° inclination angle, so that after adjacent solar cells are interconnected in the extension direction of the connection lines by intra-string interconnect members, none of the corresponding first interconnect structures in electrical contact with each of the at least one intra-string interconnect members will generate interconnect stress on the vector segment with a 45° inclination angle, and the length of the interconnect stress zone formed in the extension direction of the vector segment with a 45° inclination angle is shortened. Next, because the cleavage plane of the cell body is approximately parallel to the vector segment with a 45° inclination angle, shortening the length of the interconnect stress zone formed in the extension direction of the vector segment with a 45° inclination angle is also advantageous for shortening the length of the interconnect stress zone formed in the cleavage plane direction, which is advantageous for reducing the risk of cracking problems occurring after the solar cell is subjected to external force due to the long interconnect stress zone, and improving the structural reliability of solar modules formed based on the solar cells.

[0008] In a possible implementation, the thickness of the cell body is H1, the thickness of the first interconnect structure is H2, and the ratio of H2 to H1 is 0.005 or more and 0.1 or less.

[0009] When the above technical solution is adopted, the small ratio also reduces the thickness of the first interconnection structure, which prevents an ineffective electrical interconnection with the interconnecting members within the string (reduced interconnection tension), ensuring high structural and electrical reliability of the solar module obtained after interconnection. The small ratio also reduces the thickness of the first interconnection structure, which indirectly prevents large carrier transmission losses in the first interconnection structure and ensures high output power of the solar cell. The large ratio also increases the thickness of the first interconnection structure, which prevents large interconnection stress between the first interconnection structure and the cell body after interconnection, further reducing the risk of the solar cell being cracked by external forces after interconnection, thereby improving the structural reliability of the solar module.

[0010] In one possible embodiment, the cross-sectional area of ​​the cell body is S1, the cross-sectional area of ​​the first interconnect structure is S2, and the ratio of S2 to S1 is 0.0003 or more and 0.02 or less. In this case, since the ratio is small, the cross-sectional area of ​​the first interconnect structure is also small, which prevents the carrier transmission resistance in the first interconnect structure from increasing and ensures high output of the solar cell. In addition, since the ratio is large, the cross-sectional area of ​​the first interconnect structure is also large, which prevents the shading loss of the cell from increasing and ensures high conversion efficiency of the solar cell.

[0011] In a possible implementation, N2 is equal to 0. In this case, the number of first interconnect structures intersecting the target line segment is 0. Because the diagonal direction within the surface of the semiconductor wafer used to manufacture the solar cell is approximately parallel to the cleavage plane, the number of first interconnect structures provided on the cleavage plane of the cell body parallel to the extension direction of the target line segment is 0, which minimizes the risk of cracking problems occurring on the cleavage plane after the solar cell is subjected to external force and improves the structural reliability of the solar module formed based on the solar cell.

[0012] In a possible implementation, the distance between the geometric center of the first interconnect structure intersecting the target line segment or the vector line segment with a 45° tilt angle and the center line of the solar cell in the second direction is D3, and the distance between the geometric center of the first interconnect structure intersecting the target line segment or the vector line segment with a 45° tilt angle and the edge of the solar cell in the second direction is D4. D3>D4 corresponds to at least one first interconnect structure. In this case, the smaller distance between the geometric center of the first interconnect structure intersecting the target line segment or the vector line segment with a 45° tilt angle and the edge of the solar cell in the second direction is advantageous to prevent the first interconnect structures intersecting the target line segment or the vector line segment with a 45° tilt angle from being densely distributed on the center line of the solar cell in the second direction, thereby reducing the risk of cracking from the position where the center line of the solar cell in the second direction intersects the target line segment (or the vector line segment with a 45° tilt angle) after interconnection, and further improving the structural reliability of the solar module formed based on the solar cell. Next, as the number of first interconnection structures increases, it is also possible to balance the uniformity of current collection by the collecting electrodes and the feasibility of interconnecting adjacent solar cells, which is advantageous for improving the operating performance of the solar module.

[0013] In a possible implementation, the solar cell is a solar cell without a main grid. In the second direction, the target surface includes a central region and an edge region. At least a part of the current collecting electrode located in the edge region is in direct contact with the first interconnect structure.

[0014] When the above technical solution is adopted, when the solar cell is a solar cell without a main grid, the carriers collected by the corresponding collecting electrode can be directly transmitted to the intra-string interconnection member, such as a solder ribbon, through the first interconnection structure that is in contact with the corresponding collecting electrode, and then led out, without having to be conducted through the bus electrode and then sequentially transmitted to the first interconnection structure and the intra-string interconnection member, thereby eliminating the transmission loss of carriers in the bus electrode, reducing shading loss, and improving the operating efficiency of the solar cell.

[0015] In a possible implementation, the solar cell has a back-contact substrate structure, and the current collecting electrodes include first and second current collecting electrodes of opposite polarity, the first and second current collecting electrodes being alternately spaced apart in the second direction, and at least a portion of the first current collecting electrode in the edge region is in direct contact with the first interconnect structure, and at least a portion of the second current collecting electrode in the edge region is in direct contact with the first interconnect structure.

[0016] In a possible implementation, the solar cell further includes second interconnect structures disposed on the target surface. Each second interconnect structure is electrically connected to at least one collecting electrode, and the size of the second interconnect structures is smaller than the size of the first interconnect structure. At least a portion of the second interconnect structures is located on the same straight line and is collinear with the connecting line. Of all the collecting electrodes located on the same target surface, some of the collecting electrodes contact the first interconnect structures, and the remaining collecting electrodes contact the second interconnect structures. Here, the collecting electrodes in contact with the first interconnect structures are connecting electrodes. The distance between two adjacent connecting electrodes in the second direction is D1. At least one connecting electrode located in the edge region contacts multiple first interconnect structures, and different first interconnect structures in contact with the same connecting electrode are distributed at intervals in the first direction. The distance between the geometric centers of two adjacent first interconnect structures in contact with the same connecting electrode is D2. D2 corresponding to at least one pair of first interconnect structures is not equal to D1, and the first interconnect structures of each pair are two adjacent first interconnect structures that contact the same connecting electrode.

[0017] When the above technical solution is adopted, among all the current collecting electrodes located on the same target surface, some of the current collecting electrodes contact the large-sized first interconnection structure, thereby increasing the contact area between the some of the current collecting electrodes and the intra-string interconnection members, which is beneficial for reducing the contact resistance between the intra-string interconnection members and the current collecting electrodes and for improving the connection strength between the intra-string interconnection members and the current collecting electrodes. Next, the remaining current collecting electrodes contact the small-sized second interconnection structure, which is beneficial for reducing metal composite loss on the target surface side and for improving the operating efficiency of the solar cell. Furthermore, in the solar cell, the first interconnection structures in the same layer that contact different connection electrodes are aligned in the first direction, which reduces the connection difficulty of automatic interconnection devices such as stringers that interconnect adjacent solar cells. In this case, when D2 corresponding to at least one pair of first interconnect structures is not equal to D1, the inclination angle of the line connecting the first interconnect structure of a certain layer provided on a certain connection electrode and the first interconnect structure of an adjacent layer provided on an adjacent connection electrode is not equal to 45°, and therefore the inclination angle of the interconnect stress zone corresponding to the pair of first interconnect structures is not equal to 45°, which is advantageous for shortening the length of the interconnect stress zone formed in the extension direction of the vector line segment with an inclination angle of 45° and is also advantageous for shortening the length of the interconnect stress zone formed in the cleavage plane direction, which is advantageous for reducing the risk of cracking problems occurring after the solar cell is subjected to external force due to the long interconnect stress zone, and improving the structural reliability of the solar module formed based on the solar cell.

[0018] In a possible implementation, the number of second interconnect structures intersecting the target line segment or the vector line segment with a 45° tilt angle is N7, where N7>(1 / 3)N1, and / or N7 <N1である。

[0019] When the above technical solution is adopted, when the number N7 of second interconnect structures intersecting with the target line segment or the vector line segment with a 45° inclination angle is greater than (1 / 3)N1, the distribution density of the second interconnect structures on the target surface can be increased to ensure sufficient interconnect strength. Furthermore, in the high-temperature process of solar cell manufacturing, the electrode sintering temperature is generally above 600°C. Due to the difference in thermal expansion coefficients during the sintering and cooling processes, relatively large stress exists between the large-sized first interconnect structure and the cell body. If the stress is too large, cell cracks are likely to occur. Even if the above second interconnect structure is small in size, in the case of a solar cell without a main grid, the distribution density of the second interconnect structures on the target surface may be high, which may intensify the formation of hidden cracks within the solar cell without a main grid, leading to the risk of cell cracking. Based on this, when N7 is smaller than N1, it can be ensured that none of the second interconnect structures on at least one connection line on the target surface that can intersect with the target line segment (or vector line segment with a 45° inclination angle) is located on the target line segment (or vector line segment with a 45° inclination angle), so that after adjacent solar cells are interconnected in the extension direction of the connection line by the intra-string interconnect member, none of the corresponding second interconnect structures that intersect with at least one intra-string interconnect member will generate sintering stress on the target line segment, and the sintering stress formed in the extension direction of the target line segment will be reduced, preventing an increase in the risk of cracking of solar cells due to a large distribution density of the second interconnect structures on the target surface and ensuring a high yield of solar cells.

[0020] In a possible implementation, when the current collecting electrodes in contact with the first interconnect structures are connecting electrodes, the ratio of D1 to D2 corresponding to at least one pair of first interconnect structures is 6 or more and 12 or less.

[0021] When the above technical solution is adopted, the ratio of D1 to D2 corresponding to at least one pair of first interconnect structures within the above range is advantageous in that the small ratio prevents the extension direction of the interconnect stress zone corresponding to at least one pair of first interconnect structures from approaching the extension direction of the cleavage plane, thereby ensuring the length of the interconnect stress zone formed in the cleavage plane direction.In addition, the large ratio also increases the distance between two adjacent first interconnect structures contacted by the same connecting electrode, which is advantageous in preventing large carrier transmission loss in the connecting electrode, and is advantageous in improving the operating efficiency of the solar cell.

[0022] In one possible implementation, the solar cell further includes bus electrodes provided on the target surface. Different bus electrodes located on the same target surface extend in the second direction and are spaced apart in the first direction. Each bus electrode is electrically connected to a current collecting electrode of the same polarity as itself and is in contact with at least one first interconnect structure. Different bus electrodes correspond one-to-one to different connecting lines.

[0023] When the above technical solutions are adopted, in actual application processes, the line width of the collecting electrode is generally small to reduce the light-blocking area thereof, which makes the collecting electrode relatively easy to break. The presence of bus electrodes allows carriers collected by the portions on both sides of the break in the collecting electrode to be transmitted to the connected bus electrodes, respectively, for discharge, thereby improving current collection capability and reducing power loss.

[0024] In a possible implementation, the bus electrode is a connection electrode. Here, the distance between two adjacent connection electrodes in the first direction is D1. At least one connection electrode contacts multiple first interconnection structures, and different first interconnection structures contacting the same connection electrode are spaced apart in the second direction. The distance between the geometric centers of two adjacent first interconnection structures contacting the same connection electrode is D2. D2 corresponding to at least one pair of first interconnection structures is not equal to D1, and each pair of first interconnection structures is two adjacent first interconnection structures contacting the same connection electrode. The beneficial effects of this case can be seen from the previous paragraph, and a detailed description will be omitted here.

[0025] In a possible embodiment, the collecting electrodes include first and second collecting electrodes of opposite polarities. The first and second collecting electrodes are alternately spaced apart and distributed in the second direction. The bus electrodes include first and second bus electrodes of opposite polarities. The first and second bus electrodes are both alternately spaced apart and distributed in the first direction. The bus electrodes and collecting electrodes of opposite polarities are insulated from each other.

[0026] In a possible implementation, when the bus electrodes are the connection electrodes, the ratio of D2 to D1 corresponding to the at least one pair of first interconnect structures is 1 to 1.7.

[0027] When the above technical solution is adopted, it can be understood that, for a given length of the connecting electrodes, the greater the ratio of D2 to D1 corresponding to at least one pair of first interconnecting structures, the greater the distance between two adjacent first interconnecting structures contacted by the same connecting electrodes. Conversely, the smaller the ratio of D2 to D1 corresponding to at least one pair of first interconnecting structures, the smaller the distance between two adjacent first interconnecting structures contacted by the same connecting electrodes. However, the closer the ratio is to 1, the closer the inclination angle of the connecting line between the pair of first interconnecting structures is to 45°, i.e., closer to the extension direction of the cleavage plane. In this case, keeping the ratio of D2 to D1 corresponding to at least one pair of first interconnecting structures within the above range is advantageous for preventing the extension direction of the interconnect stress zone corresponding to at least one pair of first interconnecting structures from approaching the extension direction of the cleavage plane due to the small ratio, thereby ensuring the shortening of the length of the interconnect stress zone formed in the cleavage plane direction. Furthermore, because this ratio is large, the distance between two adjacent first interconnect structures that are in contact with the same connecting electrode also becomes large, which is advantageous in preventing large carrier transmission losses in the connecting electrode and is advantageous in improving the operating efficiency of the solar cell.

[0028] In a second aspect, the present application provides another solar cell including a cell body, a current collecting electrode, and a first interconnect structure. The cell body has opposing first and second surfaces. At least one of the first and second surfaces is a target surface. The current collecting electrode is provided on the target surface. Different current collecting electrodes located on the same target surface all extend in a first direction and are spaced apart in a second direction. The first direction is perpendicular to the second direction. The first interconnect structure is formed in an array on the target surface. Each first interconnect structure is electrically connected to at least one current collecting electrode. At least some regions of different first interconnect structures spaced apart in the second direction are located on the same connection line, and the different connection lines are spaced apart in the first direction. Here, the number of connection lines located on the same target surface is N1, and the number of first interconnect structures intersecting target line segments located on the target surface is N2, where N1>N2, and the target line segments are diagonals of the target surface and intersect all of the connection lines.

[0029] When the above technical solution is adopted, the target line segment is the diagonal line of the target plane and intersects with any of the connection lines. Also, when N2 < N1, it can be ensured that none of the first interconnecting structures where each of at least one connection line in the target plane that can intersect the target line segment is in electrical contact is provided on the target line segment. Thus, after adjacent solar cells are interconnected in the extending direction of the connection lines by the in-string interconnecting members, none of all the corresponding first interconnecting structures that are in electrical contact with each of at least one in-string interconnecting member generates an interconnecting stress on the target line segment, and the interconnecting stress formed in the extending direction of the target line segment is reduced. In this case, the direction of the diagonal line within the surface of the semiconductor wafer used in the manufacture of the solar cell is substantially parallel to the cleavage plane, and the cleavage plane is a plane having the property that a mineral crystal can be broken along a strictly certain crystallization direction by an external force to form a smooth surface. Therefore, corresponding to the silicon wafer, when a single-crystal silicon crystal bar is wire-cut, a substantially rectangular silicon wafer is formed, and the cleavage plane intersects the silicon wafer surface and is not parallel to the edge of the silicon wafer. There are innumerable cleavage planes parallel to each other within the crystal bar, forming innumerable target line segments parallel to the silicon wafer surface. Among them, the target line segment corresponding to the diagonal line of the silicon wafer is the longest and the stress problem is greater. Therefore, when the target line segment is the diagonal line of the target plane, it can be understood that the extending direction of the target line segment is substantially parallel to the direction of the cleavage plane of the battery body. At this time, the reduction of the interconnecting stress formed in the extending direction of the target line segment corresponds to the reduction of the interconnecting stress formed in the cleavage plane direction. Since the interconnecting stress is large, the risk of cracking problems occurring after the solar cell is subjected to an external force is reduced, and the structural reliability of the solar module formed based on the solar cell is improved.

[0030] In a possible implementation, the solar cell further includes bus electrodes disposed on the target surface. Different bus electrodes located on the same target surface extend in the second direction and are spaced apart in the first direction. Each bus electrode is electrically connected to a collecting electrode of the same polarity as itself and is in contact with at least one first interconnect structure. Different bus electrodes correspond one-to-one to different connecting lines. In this case, in actual application processes, the collecting electrodes generally have small line widths to reduce their light-blocking area, which makes the collecting electrodes relatively prone to breakage. The presence of the bus electrodes allows carriers collected by the portions of the collecting electrodes on both sides of the break to be transmitted to the connected bus electrodes, respectively, thereby improving current collection capability and reducing power loss.

[0031] In a possible implementation, when the solar cell includes at least two divided battery cells spaced apart in the second direction, a scribe line is provided between two adjacent divided battery cells. The opposite-polarity current collecting electrodes of the two adjacent divided battery cells are arranged symmetrically with respect to the scribe line, and / or the opposite-polarity first interconnect structures of the two adjacent divided battery cells are arranged symmetrically with respect to the scribe line, and / or the opposite-polarity bus electrodes of the two adjacent divided battery cells are arranged symmetrically with respect to the scribe line. In this case, at least one of the opposite-polarity current collecting electrodes, the first interconnect structure, and the bus electrodes of the two adjacent divided battery cells is arranged symmetrically with respect to the scribe line, which facilitates interconnection between them, prevents misalignment, improves the interconnection yield, and reduces the difficulty of interconnection.

[0032] In a possible implementation, the solar cell includes M divided battery cells spaced apart in the second direction, where M is a positive integer greater than or equal to 1. In the same divided battery cell, the geometric centers of two first interconnect structures located at the edges in the second direction are arranged symmetrically with respect to the center line of the divided battery cell in the second direction.

[0033] When the above technical solution is adopted, for the same divided battery cell, the geometric centers of the two first interconnection structures located on the edges in the second direction are arranged symmetrically with respect to the center of the divided battery cell in the second direction, so that an automatic interconnection device such as a stringer can interconnect different divided battery cells at the same starting position. This prevents misalignment between intra-string interconnection members such as solder ribbons and the first interconnection structures provided on the battery body due to differences in the starting positions corresponding to different divided battery cells, and further prevents carriers in the connection electrodes corresponding to the first interconnection structures that are not electrically connected to the intra-string interconnection members from being unable to be guided through the intra-string interconnection members, resulting in power loss or the corresponding first interconnection structures becoming a load and reducing the operating efficiency of the solar cell. This ensures that the solar module formed based on the solar cell provided in the present application has good operating performance.

[0034] In a possible implementation, the solar cell has a back-contact substrate structure, and the current collecting electrodes include first and second current collecting electrodes of opposite polarity, the first and second current collecting electrodes being alternately spaced apart in the second direction, and at least a portion of the first current collecting electrode in the edge region is in direct contact with the first interconnect structure, and at least a portion of the second current collecting electrode in the edge region is in direct contact with the first interconnect structure.

[0035] In a possible implementation, when the polarities of the two bus electrodes located on the outside in the first direction are opposite, at least two of all the first interconnection structures that intersect with the target line segment are equidistant from the center line of the target surface in the second direction and have the same polarity, which is advantageous for improving the distribution uniformity between first interconnection structures of different polarities located on the same target surface and for reducing the difficulty of interconnecting adjacent solar cells using an automatic interconnection device such as a stringer.

[0036] As a possible implementation form, when the solar cell includes two divided cell units that are spaced apart and distributed in the second direction, the N2 corresponding to the two divided cell units is equal. In the same divided cell unit, the polarities of the two bus electrodes located on the outer side in the first direction are opposite. The polarities of the two bus electrodes that belong to different divided cell units and are oppositely provided on the outer side in the first direction are opposite. In this case, it is beneficial to improve the symmetry between the different first interconnect structures with opposite polarities located on the same target surface, and it is beneficial to reduce the difficulty of realizing the interconnection of adjacent solar cells by an automatic interconnection device such as a stringer.

[0037] As a possible implementation form, when the solar cell includes two divided cell units that are spaced apart and distributed in the second direction, the N2 corresponding to the two divided cell units is not equal. In the same divided cell unit, the polarities of the two bus electrodes located on the outer side in the first direction are the same. The polarities of the two bus electrodes that belong to different divided cell units and are oppositely provided on the outer side in the first direction are opposite. In this case, another possible implementation form of the solar cell provided in the present application is provided, and the applicability of the solar cell provided in the present application in different application scenarios is improved.

[0038] As a possible implementation form, the above-mentioned solar cell is a solar cell without a main grid. The solar cell further includes a second interconnect structure provided on the target surface. Each second interconnect structure is electrically connected to at least one current collecting electrode, and the size of the second interconnect structure is smaller than the size of the first interconnect structure. At least a part of the region of the second interconnect structure is located on the same straight line and is collinear with the connection line. Among all the current collecting electrodes located on the same target surface, some current collecting electrodes are in contact with the first interconnect structure, and the remaining current collecting electrodes are in contact with the second interconnect structure. The number of the second interconnect structures intersecting the target line segment is N8, where N8 > (1 / 2)N1 and / or N8 < 1.5N1. The application principle of the beneficial effect in this case can refer to the application principle of the beneficial effect that N7 > (1 / 3)N1 and N7 < N1 described above, and the detailed description is omitted here.

[0039] In a third aspect, the present application provides a solar module including a solar cell as provided in the first aspect and its various implementations, or including a solar cell as provided in the second aspect and its various implementations.

[0040] The beneficial effects of the third aspect of the present application and its various implementation forms may refer to the analysis of the beneficial effects of the first aspect and its various implementation forms, or may refer to the analysis of the beneficial effects of the second aspect and its various implementation forms, and detailed description thereof will be omitted here.

[0041] In a fourth aspect, the present application provides another solar module including a solar cell and an intra-string interconnection member connecting two adjacent solar cells in series. The solar cell includes a cell body, a current collecting electrode, and a first interconnection structure. The cell body has opposing first and second surfaces. At least one of the first and second surfaces is a target surface. The current collecting electrodes are provided on the target surface. Different current collecting electrodes located on the same target surface all extend in a first direction and are spaced apart in a second direction. The first direction is perpendicular to the second direction. Each first interconnection structure is electrically connected to at least one current collecting electrode. Each intra-string interconnection member is in electrical contact with a corresponding first interconnection structure. The number of first interconnection structures intersecting with a target line segment located in the target surface is N2, and the target line segment is a line segment connecting the midpoint of the longer of two edges extending in the first direction of the target surface and distributed opposite to each other, to the apex corner corresponding to the shorter of the two edges. The number of intra-string interconnection members located on the same target plane is N5. The number of first interconnection structures intersecting with at least one identical 45° oblique vector line segment is N4. The number of intra-string interconnection members intersecting with the identical 45° oblique vector line segment is N6, where N2<(1 / 2)N5 or N6>N4.

[0042] In a possible implementation, N2 is equal for at least two solar cells in the same solar module.

[0043] The beneficial effects of the fourth aspect of the present application and its various implementation forms may refer to the analysis of the beneficial effects of the first aspect and its various implementation forms, and detailed description thereof will be omitted here. [Brief explanation of the drawings]

[0044] The drawings described herein are intended to further the understanding of the present application and constitute a part of the present application, and the illustrative embodiments and the description thereof are intended to interpret the present application and are not intended to unduly limit the present application. [Figure 1] 1 is a schematic diagram of a first structure of a solar cell provided in an embodiment of the present application. [Figure 2] FIG. 2 is a schematic diagram of a second structure of a solar cell provided in an embodiment of the present application. [Figure 3] FIG. 2 is a schematic diagram of a third structure of a solar cell provided in an embodiment of the present application. [Figure 4] FIG. 2 is a schematic diagram of a fourth structure of a solar cell provided in an embodiment of the present application. [Figure 5] FIG. 2 is a schematic cross-sectional view of a semiconductor substrate for manufacturing a battery body in an example of the present application. [Figure 6] FIG. 2 is a schematic diagram of a distribution of diagonal lines on a target surface in an example of the present application. [Figure 7] FIG. 2 is a schematic diagram showing the distribution relationship between a portion of a connection electrode and a portion of an interconnection structure in an example of the present application. [Figure 8] FIG. 1 is a schematic diagram of a fifth structure of a solar cell provided in an embodiment of the present application. [Figure 9] FIG. 1 is a schematic diagram of a sixth structure of a solar cell provided in an embodiment of the present application. [Figure 10] FIG. 1 is a schematic diagram of a seventh structure of a solar cell provided in an embodiment of the present application. [Figure 11] FIG. 10 is a schematic diagram of the eighth structure of the solar cell provided in the examples of the present application. [Figure 12] FIG. 10 is a schematic diagram showing another distribution relationship between a portion of a connection electrode and a portion of an interconnection structure in an embodiment of the present application. [Figure 13]FIG. 10 is a schematic diagram of the ninth structure of the solar cell provided in the examples of the present application. [Figure 14] FIG. 12 is a schematic diagram of the tenth structure of the solar cell provided in the examples of the present application. DETAILED DESCRIPTION OF THE INVENTION

[0045] Hereinafter, embodiments of the present application will be described with reference to the drawings. However, it should be understood that these descriptions are merely illustrative and do not limit the scope of the present application. In addition, in the following description, descriptions of known structures and techniques are omitted so as not to unnecessarily obscure the concept of the present application.

[0046] The drawings show schematic diagrams of various structures according to the embodiments of the present application. These drawings are not drawn to scale, and certain details may be enlarged or omitted for clarity. The shapes of various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are for illustrative purposes only. In reality, differences may occur due to manufacturing tolerances or technical limitations, and those skilled in the art can separately design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0047] In the context of this application, when a layer / element is referred to as being "on" another layer / element, the layer / element may be located directly on the other layer / element, or there may be an intervening layer / element therebetween. Also, if a layer / element is "on" another layer / element in one orientation, the layer / element may be "under" the other layer / element when the orientation is reversed. In order to make the technical problems, technical solutions, and beneficial effects of the present application clearer and easier to understand, the present application will be described in more detail below with reference to the drawings and examples. It should be understood that the specific examples described herein are merely for the purpose of interpreting the present application and are not intended to limit the present application.

[0048] Additionally, the terms "first" and "second" are for descriptive purposes only and should not be understood to indicate or imply relative importance or the quantity of the indicated technical features. Thus, a feature qualified as "first" or "second" may expressly or imply the inclusion of one or more of the feature. In this description, unless expressly and specifically limited, "plurality" means two or more than two. Unless expressly and specifically limited, "some" means one or more than one.

[0049] In the description of this application, unless otherwise clearly specified or limited, the terms "attach," "couple," and "connect" should be understood in a broad sense, and may refer to, for example, fixed connection, detachable connection, integral connection, mechanical connection, electrical connection, direct connection, or indirect connection via an intermediate medium, or to communication between the interiors of two elements, or to an interactive relationship between two elements. Those skilled in the art can understand the specific meanings of the above terms in this application according to specific circumstances.

[0050] Currently, solar cells are increasingly being used as a new alternative energy source. Among them, photovoltaic solar cells are devices that convert light energy from the sun into electrical energy. Specifically, solar cells use the principle of photovoltaic power to generate carriers, and then use electrodes to extract the carriers, which is advantageous for the effective use of electrical energy.

[0051] Specifically, conventional solar cells typically include a cell body, current collecting electrodes, and an interconnection structure. The current collecting electrodes are provided on a first surface and / or a second surface of the solar cell. Different current collecting electrodes located on the same surface all extend in a first direction and are spaced apart in a second direction. The first direction is different from the second direction. The interconnection structure is provided on the surface of the cell body having the current collecting electrodes, and is a conductive structure for achieving electrical connection between the solar cells and the intra-string interconnection members. Each interconnection structure contacts at least one current collecting electrode and achieves interconnection between adjacent solar cells via the interconnection structure and the intra-string interconnection member, such as a solder ribbon. Different interconnection structures located on the same surface form an array. At least some regions of the different interconnection structures spaced apart in the second direction are located on the same connection line, and the different connection lines are spaced apart in the first direction. Here, the specific meaning of the connection line can be determined depending on the type of solar cell. Specifically, if the solar cell is a solar cell without a main grid, the connection line overlaps with the orthogonal projection of the intra-string interconnection member on the cell body, or the connection line is a virtual line formed in the interconnection direction by an interconnection structure of the same polarity. If the solar cell is a solar cell with a main grid, the connection line overlaps with the orthogonal projection of the bus electrode on the cell body. If the solar cell is applied to a solar module, the connection line overlaps with the orthogonal projection of the intra-string interconnection member on the cell body. In the case of a whole battery, the number of connection lines refers to the number of connection lines in a single divided battery cell on the same plane. In the case of a solar cell with a back-contact substrate structure, the number of connection lines refers to the total number of connection lines corresponding to the positive and negative interconnection structures on the back surface of the cell.

[0052] However, in the above-mentioned conventional solar cells, the distribution of the interconnect structures on the cell body is not rational. Specifically, taking the entire cell as an example, in conventional solar cells, the number of connection lines is equal to or less than the number of interconnect structures intersecting the diagonal line. The diagonal line is the longest line segment on the surface of the cell body. In this case, after adjacent solar cells are electrically connected to the interconnect structure in the direction of extension of the connection lines using intra-string interconnect members such as solder ribbons to interconnect the adjacent solar cells, stress occurs between the interconnect structure and the cell body on the surface where the interconnect structure is formed after interconnection due to differences in material and thermal expansion coefficients between the interconnect structure and the cell body. Generally, the battery body has a smaller thermal expansion coefficient than the interconnect structure, resulting in a stress difference between the two. Meanwhile, the main material of the battery body is generally a brittle silicon material, and large stress on its surface can cause cracks. Typically, the ratio of the thermal expansion coefficients of the battery body and the interconnect structure is greater than 10. For example, if the battery body is made of silicon, the electrodes are silver, and the interconnecting members within the string are copper solder ribbons, the thermal expansion coefficient of the battery body is 2.6 x 10 -6 / °C, and the thermal expansion coefficient of the silver electrode is 1.9 x 10 -5 / ℃, and the difference in the thermal expansion coefficient between the two is large. The thermal expansion coefficient of copper solder ribbon is 1.7×10 -5 / °C, and the interconnection and packaging temperatures are generally around 150°C or higher, which means that the difference in thermal expansion coefficient with the battery body is large, causing stress to concentrate at the location of the interconnection structure. Based on this, if the number of connection lines is equal to or less than the number of interconnection structures crossing the diagonal, each connection line will have at least one interconnection structure crossing the diagonal, and after interconnection, a long stress zone extending in the diagonal direction will be formed, resulting in excessive interconnection stress in the diagonal direction. The diagonal direction is approximately parallel to the cleavage plane of the battery body, and excessive interconnection stress in the diagonal direction is likely to significantly increase the risk of cracking and reduce the structural reliability of the solar module.

[0053] To solve the above technical problems, in a first aspect, the present invention provides a solar cell. Specifically, the solar cell provided in the present invention may be any cell that can convert solar energy into electrical energy.

[0054] Regarding the arrangement positions of the positive and negative electrodes, the solar cell provided in the examples of the present application may have a double-sided contact substrate structure, i.e., one of the positive and negative electrodes of the solar cell is disposed on the front side of the solar cell and the other is disposed on the back side, or the solar cell provided in the examples of the present application may have a back-contact substrate structure, i.e., both the positive and negative electrodes of the solar cell are disposed on the back side of the solar cell.

[0055] Regarding the specific electrode structures of the positive and negative electrodes, the solar cell provided in the examples of the present application may be a "solar cell with a main grid," in which the solar cell includes not only collecting electrodes but also bus electrodes, with different bus electrodes corresponding one-to-one to different connecting lines. Alternatively, the solar cell provided in the examples of the present application may be a "solar cell without a main grid," in which the solar cell without a main grid does not have the bus electrodes of the solar cell with a main grid. Specifically, the electrode structure of a solar cell without a main grid may include only collecting electrodes, or may include collecting electrodes and bus electrode segments that assist in current collection (the bus electrode segments may be electrically connected to first interconnect structures located at the edges in the second direction and extend toward the edges of the cell body in the second direction). The specific shape of the bus electrode segments is not limited and may be, for example, linear, curved, or curved.

[0056] Specifically, as shown in FIGS. 2, 4, 5, and 6, the solar cell provided in the embodiments of the present application includes a cell body 11, a current collecting electrode 12, and a first interconnection structure 13. The cell body 11 has opposing first and second surfaces. At least one of the first and second surfaces is a target surface. The current collecting electrode 12 is provided on the target surface. Different current collecting electrodes 12 located on the same target surface all extend in a first direction and are spaced apart in a second direction. The first direction is perpendicular to the second direction. The first interconnection structures 13 are formed in an array on the target surface. Each first interconnection structure 13 is electrically connected to at least one current collecting electrode 12. At least some regions of different first interconnection structures 13 spaced apart in the second direction are located on the same connecting line, and different connecting lines are spaced apart in the first direction. Here, the number of connection lines located within the same target surface is N1, the number of first interconnect structures 13 intersecting with target line segments located within the target surface is N2, where N2<(1 / 2)N1, and the target line segments are line segments connecting the midpoint of the longer of two edges extending in a first direction of the target surface and distributed opposite to each other to the apex end point of the shorter of the two edges. Alternatively, the number of connection lines intersecting with vector line segments with a 45° inclination angle is N3, and the number of first interconnect structures 13 intersecting with at least one same 45° inclination vector line segment is N4, where N3>N4.

[0057] Specifically, the number N1 of the connecting lines is a positive integer greater than or equal to 1. The number N2 of the first interconnect structures intersecting with the target line segments located within the target surface is an integer greater than or equal to 0. Next, it can be understood that there are countless vector line segments with a tilt angle of 45° within the target surface of the solar cell, and among them, at least one vector line segment with a tilt angle of 45° satisfies N3>N4.

[0058] 2 and 4, in the solar cell provided in the embodiment of the present application, first interconnection structures 13 are provided on the target surface of the cell body 11, and the first interconnection structures 13 are arrayed on the target surface. Each first interconnection structure 13 is electrically connected to at least one collecting electrode 12. Furthermore, at least some regions of different first interconnection structures 13 spaced apart in the second direction are located on the same connecting line, and different connecting lines are spaced apart in the first direction. In this case, when adjacent solar cells are interconnected in the extension direction of the connecting line by intra-string interconnection members such as solder ribbons, the intra-string interconnection members corresponding to the connecting line one-to-one are electrically connected to collecting electrodes 12 of the same polarity located on the target surface via at least the first interconnection structures 13. Carriers collected by the collecting electrodes 12 can be sequentially guided through the first interconnection structures 13 and the intra-string interconnection members to form photocurrent. After adjacent solar cells are interconnected, interconnection stress occurs due to the difference in material and thermal expansion coefficient between the first interconnection structure 13 and the cell body 11. Based on this, a target line segment contacts up to half of the connecting lines located on the same target surface. Furthermore, when N2<(1 / 2)N1, it can be ensured that none of the first interconnection structures 13 electrically contacting at least one connecting line on the target surface that can intersect with the target line segment are provided on the target line segment. Therefore, after adjacent solar cells are interconnected in the extension direction of the connecting lines by the intra-string interconnection members, no interconnection stress occurs on the target line segment for any of the corresponding first interconnection structures 13 electrically contacting at least one intra-string interconnection member, thereby reducing the interconnection stress formed in the extension direction of the target line segment.In this case, the direction of the diagonal line within the surface of the semiconductor wafer used in manufacturing solar cells is approximately parallel to the cleavage plane, which is a plane that has the property of allowing mineral crystals to be ruptured in a strictly fixed crystallization direction by an external force and break into a smooth surface. Therefore, when a single-crystal silicon rod is wire-cut to correspond to a silicon wafer, an approximately rectangular silicon wafer is formed, and the cleavage plane intersects with the surface of the silicon wafer and is not parallel to the edge of the silicon wafer. There are countless parallel cleavage planes within the crystal bar, forming countless target segments parallel to the silicon wafer surface. Among these, the target segments corresponding to the diagonals of the silicon wafer are the longest and experience greater stress. However, the positions of the target segments before and after the silicon wafer is cut in half remain unchanged. Therefore, when a target segment is a line segment connecting the midpoint of the longer of two edges (e.g., the non-chamfered edge) that extend in a first direction on the target surface and the apex end point of the shorter of the two edges (e.g., the chamfered edge), the extension direction of the target segment can be understood to be approximately parallel to the direction of the cleavage planes of the cell body 11. In this case, reducing the interconnect stress formed in the extension direction of the target segment corresponds to reducing the interconnect stress formed in the cleavage plane direction. This reduces the risk of cracking of the solar cell after external force is applied due to high interconnect stress, thereby improving the structural reliability of solar modules formed based on the solar cell. Next, when the number N3 of connection lines intersecting with the vector line segment with a 45° inclination angle is greater than the number N4 of first interconnect structures 13 intersecting with it, all of the first interconnect structures 13 on at least one connection line are not located on the vector line segment with a 45° inclination angle, so that after adjacent solar cells are interconnected in the extension direction of the connection lines by intra-string interconnect members, none of the corresponding first interconnect structures 13 that are in electrical contact with each of the at least one intra-string interconnect members will generate interconnect stress on the vector line segment with a 45° inclination angle, and the length of the interconnect stress zone formed in the extension direction of the vector line segment with a 45° inclination angle is shortened.Next, since the cleavage plane of the cell body 11 is approximately parallel to the vector line segment with a tilt angle of 45°, shortening the length of the interconnect stress zone formed in the extension direction of the vector line segment with a tilt angle of 45° is also advantageous for shortening the length of the interconnect stress zone formed in the cleavage plane direction, which is advantageous for reducing the risk of cracking problems occurring after the solar cell is subjected to external force due to the long interconnect stress zone, and improves the structural reliability of the solar module formed based on the solar cell.

[0059] It should be noted that the solar cell provided in the first aspect of the embodiment of the present application is a half-cut solar cell. Next, the direction of the diagonal line in the surface of the semiconductor wafer used in manufacturing the solar cell mentioned in the preceding sentence (i.e., the diagonal line in the target surface of the cell body of the whole cell), the direction of the vector line segment with a tilt angle of 45°, and the direction of the target line segment in the half-cut solar cell are all approximately parallel to the cleavage plane, so even if the direction of the diagonal line in the target surface of the cell body of the whole cell, the direction of the vector line segment with a tilt angle of 45°, and the direction of the target line segment in the half-cut solar cell described in the present specification are replaced with the extension direction of the cleavage plane, the corresponding relationship is satisfied.

[0060] In addition, in an actual application process, the number N1 of connecting lines located on the target surface and the number N2 of first interconnect structures intersecting with the target line segments within the target surface can be determined according to the distance between two adjacent connecting lines or the distance between two adjacent collecting electrodes electrically contacting the first interconnect structures in the second direction, and the distribution of the first interconnect structures on the connecting lines, as long as they are applicable to the solar cells provided in the embodiments of the present application.

[0061] 4, N2 may be equal to 0. In this case, the number of first interconnect structures 13 intersecting the target line segment is 0. The direction of a diagonal line within the surface of a semiconductor wafer used to manufacture a solar cell is approximately parallel to the cleavage plane. Furthermore, after the semiconductor wafer is cut in half, the position of a line segment (i.e., the target line segment) connecting the midpoint of the longer of two edges extending in the first direction of the target surface and distributed opposite to each other to the apex end point of the shorter of the two edges is the position of a diagonal line within the surface of the entire original semiconductor wafer. Therefore, it can be seen that the target line segment is approximately parallel to the cleavage plane. In this case, the number of first interconnect structures 13 arranged on the cleavage plane of cell body 11 parallel to the extension direction of the target line segment is 0. This minimizes the risk of cracking problems occurring on the cleavage plane after the solar cell is subjected to external force, and improves the structural reliability of solar modules formed based on the solar cell. It should be noted that when N2 is equal to 0, it is applicable to solar cells without a main grid, solar cells with a main grid, back-contact substrate structures, and double-sided contact substrate structures.

[0062] The number N3 of connecting lines intersecting with the vector line segment with a 45° inclination angle and the number N4 of first interconnect structures intersecting with the same vector line segment with a 45° inclination angle can also be determined according to the distance between two adjacent connecting lines or the distance between two adjacent collecting electrodes electrically contacting the first interconnect structure in the second direction, and the distribution of the first interconnect structures on the connecting lines, as long as they are applicable to the solar cells provided in the embodiments of the present application.

[0063] Regarding the first interconnect structure, in terms of material, the material of the first interconnect structure may include any one of conductive materials such as silver, copper, aluminum or tungsten.

[0064] Second, as described above, due to differences in the materials and thermal expansion coefficients of the battery body and the first interconnect structure, interconnection stress may occur at the interface between the battery body and the first interconnect structure after interconnection. If the size of the first interconnect structure differs, the magnitude of the interconnection stress occurring at the interface between the battery body and the first interconnect structure after interconnection may also differ. Specifically, with other factors remaining the same, within a certain range, the magnitude of the interconnection stress at the interface between the first interconnect structure and the battery body after interconnection of adjacent solar cells is proportional to the thickness of the first interconnect structure. Furthermore, within a certain range, the thickness of the first interconnect structure is inversely proportional to its own transmission loss. In this case, the size of the first interconnect structure can be determined at least according to the requirements for transmission loss and interconnection stress of the first interconnect structure in actual application scenarios, and is not specifically limited herein.

[0065] For example, the thickness of the cell body is H1, and the thickness of the first interconnect structure is H2. Based on this, the ratio of H2 to H1 may be 0.005 or more and 0.1 or less. For example, the ratio of the thickness H2 of the interconnect structure to the thickness H1 of the cell body may be 0.005, 0.01, 0.02, 0.04, 0.06, 0.08, or 0.1. In this case, if the ratio of the thickness H2 of the first interconnect structure to the thickness H1 of the cell body is within the above range, the small ratio reduces the thickness of the first interconnect structure, which can prevent ineffective electrical interconnection with the intra-string interconnect members (reduced interconnect tension), thereby ensuring high structural and electrical reliability of the solar module obtained after interconnection. Furthermore, the small ratio reduces the thickness of the first interconnect structure, which indirectly prevents large carrier transmission loss in the first interconnect structure and ensures high output power of the solar cell. Furthermore, since this ratio is large, the thickness of the first interconnect structure also becomes large, which prevents the interconnection stress between the first interconnect structure and the cell body from becoming large after interconnection, and further reduces the risk of the solar cell being cracked by external force after interconnection, thereby improving the structural reliability of the solar module.It should be noted that the ratio of H2 to H1 may be between 0.005 and 0.1, which can be applied to solar cells without main grids, solar cells with main grids, back-contact type substrate structures, and double-sided contact type substrate structures.

[0066] For example, the cross-sectional area of ​​the cell body is defined as S1, and the cross-sectional area of ​​the first interconnect structure is defined as S2. Based on this, the ratio of S2 to S1 may be 0.0003 or more and 0.02 or less. For example, the ratio of the cross-sectional area S2 of the interconnect structure to the cross-sectional area S1 of the cell body may be 0.0003, 0.0008, 0.001, 0.003, 0.005, 0.008, 0.01, or 0.02. When the ratio of S2 to S1 is within the above range, the small ratio results in a small cross-sectional area of ​​the first interconnect structure, thereby preventing an increase in carrier transmission resistance in the first interconnect structure and ensuring high output of the solar cell. Furthermore, the large ratio results in a large cross-sectional area of ​​the first interconnect structure, thereby preventing an increase in shading loss of the cell and ensuring high conversion efficiency of the solar cell. It should be noted that the ratio of S2 to S1 between 0.0003 and 0.02 is applicable to solar cells without a main grid, solar cells with a main grid, back-contact substrate structures, and double-sided contact substrate structures.

[0067] Furthermore, when the first interconnect structure simultaneously satisfies the requirements that the ratio of H2 to H1 is 0.005 or more and 0.1 or less, and the ratio of S2 to S1 is 0.0003 or more and 0.02 or less, the four factors of interconnect tension, resistance loss, interconnect stress, and shading loss can be balanced, ensuring that the solar cell has high conversion efficiency, and that the solar module including the solar cell provided in the embodiments of the present application has high structural reliability and electrical properties.

[0068] The distribution of the first interconnection structures on the target surface can be determined according to the distribution and number of the collecting electrodes and / or bus electrodes on the target surface, as long as it is applicable to the solar cells provided in the embodiments of the present application.

[0069] 2 and 4, the distance between the geometric center of the first interconnect structure 13 intersecting the target line segment and the center line of the solar cell in the second direction is defined as D3 (not shown). In this application, the center line in the second direction refers to a center line extending in the first direction and located at the midpoint in the second direction. The distance between the geometric center of the first interconnect structure 13 intersecting the target line segment and the edge of the solar cell in the second direction is defined as D4 (not shown). Based on this, D3 > D4 for at least one first interconnect structure 13. In this case, the smaller distance between the geometric center of the first interconnect structure 13 intersecting the target line segment and the edge of the solar cell in the second direction is advantageous in preventing the first interconnect structures 13 intersecting the target line segment from being densely distributed on the center line of the solar cell in the second direction. This reduces the risk of cracking at the intersection of the center line of the solar cell in the second direction and the target line segment after interconnection, further improving the structural reliability of the solar module formed based on the solar cell. Secondly, as the number of first interconnection structures 13 increases, it is possible to strike a balance between the uniformity of current collection by the current collecting electrodes 12 and the feasibility of interconnecting adjacent solar cells, which is beneficial to improving the operating performance of the solar module. It should be noted that the relationship D3>D4 corresponding to at least one first interconnection structure 13 can be applied to solar cells without a main grid, solar cells with a main grid, back-contact substrate structures, and double-sided contact substrate structures.

[0070] 9 and 11, the distance D3 between the geometric center of the first interconnect structure 13 intersecting the target line segment and the center line of the solar cell in the second direction may be less than or equal to the distance D4 between the geometric center of the first interconnect structure 13 intersecting the target line segment and the edge of the solar cell in the second direction. The specific values ​​of D3 and D4 can be determined according to the distribution of the first interconnect structure 13 and the collecting electrodes 12 on the target surface, and are not specifically limited herein.

[0071] Furthermore, the embodiments of the present application do not specifically limit the structure and materials of the cell body, and these can be determined according to the type of solar cell and the actual application scenario, as long as they are applicable to the solar cells provided in the embodiments of the present application.

[0072] For example, when the solar cell provided in the embodiments of the present application has a double-sided contact substrate structure, the cell body may include at least a semiconductor substrate, a first doped semiconductor layer, and a second doped semiconductor layer. One of the first doped semiconductor layer and the second doped semiconductor layer is formed on a side corresponding to the front surface of the semiconductor substrate, and the other is formed on a side corresponding to the back surface of the semiconductor substrate. In addition, the first doped semiconductor layer and the second doped semiconductor layer have opposite conductivity types.

[0073] Here, the semiconductor substrate may be a substrate made of any one of semiconductor materials such as a silicon substrate, a germanium silicon substrate, a germanium substrate, a gallium arsenide substrate, etc. The conductivity type of the semiconductor substrate may be N-type, P-type, or intrinsic type.

[0074] Regarding the first doped semiconductor layer and the second doped semiconductor layer, the material of the first doped semiconductor layer and / or the second doped semiconductor layer may include any one of semiconductor materials such as silicon, germanium silicon, or germanium. In terms of the material arrangement form, the crystalline phase of the first doped semiconductor layer and / or the second doped semiconductor layer may be amorphous, microcrystalline, nanocrystalline, single crystal, polycrystalline, or the like. In terms of conductivity type, the conductivity type of the first doped semiconductor layer may be N-type, and in this case, the conductivity type of the second doped semiconductor layer may be P-type. Alternatively, the conductivity type of the first doped semiconductor layer may be P-type, and in this case, the conductivity type of the second doped semiconductor layer may be N-type. The thicknesses of the first doped semiconductor layer and the second doped semiconductor layer can be set according to actual needs and are not specifically limited herein. For example, the thicknesses of the first doped semiconductor layer and the second doped semiconductor layer may be 100 nm or more and 500 nm or less.

[0075] For example, the solar cell may have a back-contact substrate structure, and the cell body may include at least a semiconductor substrate, a first doped semiconductor layer, and a second doped semiconductor layer. The first doped semiconductor layer and the second doped semiconductor layer have opposite conductivity types, and are both provided on the back side of the semiconductor substrate. At least a portion of the first doped semiconductor layer and at least a portion of the second doped semiconductor layer are spaced apart. For information on the materials, thicknesses, etc. of the semiconductor substrate, the first doped semiconductor layer, and the second doped semiconductor layer, please refer to the above, and detailed description will be omitted here.

[0076] Regarding the battery body having opposing first and second surfaces, the first surface of the battery body may correspond to the front surface of the solar cell, and in this case the second surface of the battery body may correspond to the back surface of the solar cell. In this case, since the connecting wire is provided on the target surface of the battery body, whether the target surface is specifically the first surface or the second surface of the battery body, or whether both the first surface and the second surface are target surfaces, can be determined according to the type of solar cell and the actual application scenario.

[0077] Here, when the solar cell has a double-sided contact substrate structure, the target surface of the cell body may be only the first surface of the cell body, only the second surface of the cell body, or both the first and second surfaces of the cell body.When the solar cell has a back-contact substrate structure, the target surface of the cell body is either the first or second surface of the cell body, which corresponds to the back surface of the solar cell.

[0078] Next, it should be explained that if the apex angle of the target surface is a sharp angle, the target line segment may be a line segment connecting the midpoint of one of two edges extending in a first direction of the target surface and distributed opposite to each other to the apex corner end point corresponding to the other edge. If the apex angle of the target surface is a chamfer with a smooth transition or the like, the target line segment may be a line segment connecting the midpoint of the longer of the two edges extending in the first direction of the target surface and distributed opposite to each other (i.e., the non-chamfered edge) to the apex corner end point (the apex corner end point is an end point of the chamfered extension line) corresponding to the shorter of the two edges (i.e., the chamfered edge).

[0079] Furthermore, the specific structure and distribution of the electrode structure formed on the target surface of the solar cell can be determined depending on the type of solar cell.

[0080] For example, as shown in FIG. 2 , in the second direction, the target surface includes a central region and an edge region. At least a portion of the current collecting electrode 12 located in the edge region is in electrical contact with the first interconnect structure 13. In this case, if the solar cell is a solar cell without a main grid, at least a portion of the current collecting electrode 12 in the central region is in contact with the second interconnect structure. Carriers collected by the corresponding current collecting electrode 12 can be directly transmitted and led out to an intra-string interconnect member, such as a solder ribbon, through the first interconnect structure 13 in contact with the corresponding current collecting electrode 12, without having to be transmitted to the first interconnect structure 13 and the intra-string interconnect member via a bus electrode. This eliminates carrier transmission loss in the bus electrode, reduces shading loss, and improves the operating efficiency of the solar cell. If the solar cell is a solar cell with a main grid, at least a portion of the current collecting electrode 12 in the central region is in contact with the first interconnect structure 13. Contacting at least a portion of the current collecting electrode 12 located in the edge region and the central region with the first interconnect structure 13 can improve the strength of the interconnection. Illustratively, the size of the first interconnect structures 13 located in the central region is smaller than the size of the first interconnect structures 13 located in the edge region.

[0081] Specifically, the above-mentioned size of the first interconnect structure in the edge region being larger than the size of the first interconnect structure in the central region may mean that, in a first direction, only the length of the first interconnect structure in the edge region is larger than the length of the first interconnect structure in the central region, or that, in a second direction, only the width of the first interconnect structure in the edge region is larger than the width of the first interconnect structure in the central region, or that the length and width of the first interconnect structure in the edge region are larger than the length and width of the first interconnect structure in the central region, respectively.

[0082] Here, the region of the target surface between the two first interconnect structures positioned at the edges in the second direction (i.e., one first interconnect structure positioned at each edge at both ends in the second direction) and the edge of the cell body is defined as the edge region of the target surface, and the remaining region is defined as the central region of the target surface. In this case, if the solar cell has a double-sided contact substrate structure, the polarities of the different current collecting electrodes positioned on the same target surface are the same (all current collecting electrodes included in the positive or negative electrode). In this case, if the solar cell does not have a main grid, the number of all connection lines includes the sum of the number of connection lines intersecting with first interconnect structures of the same polarity, i.e., the number of connection lines formed by first interconnect structures that contact the current collecting electrodes. Next, the number of first interconnect structures intersecting with target line segments positioned within the target surface also includes the number of first interconnect structures that contact the current collecting electrodes of the same polarity that intersect with the target line segments. In case the solar cell has a main grid, the number of all connection lines includes the sum of the number of connection lines corresponding to bus electrodes of the same polarity. Next, the number of first interconnect structures that intersect with target line segments located within the target surface also includes the number of first interconnect structures that intersect with the target line segments and contact bus electrodes of the same polarity.

[0083] When the solar cell has a back-contact substrate structure, all current collecting electrodes located on the same target surface include first and second current collecting electrodes of opposite polarity. The first and second current collecting electrodes are alternately spaced apart in the second direction to prevent electrical leakage. Here, at least a portion of the first current collecting electrode in the edge region is in contact with the first interconnect structure, and at least a portion of the second current collecting electrode in the edge region is in electrical contact with the first interconnect structure. Specifically, the first current collecting electrode may be a current collecting electrode included in the positive electrode, and in this case, the second current collecting electrode may be a current collecting electrode included in the negative electrode, or the first current collecting electrode may be a current collecting electrode included in the negative electrode, and in this case, the second current collecting electrode is a current collecting electrode included in the positive electrode. In this case, if the solar cell is a solar cell without a main grid, the number of all connection lines includes the sum of the number of connection lines intersecting with first interconnect structures of two polarities, i.e., the sum of the number of first connection lines formed by first interconnect structures in contact with the first current collecting electrode and the number of second connection lines formed by first interconnect structures in contact with the second current collecting electrode. Next, the number of first interconnect structures intersecting with target line segments located within the target surface also includes the sum of the number of first interconnect structures of two polarities intersecting with target line segments located within the same target surface, i.e., the sum of the number of first interconnect structures in contact with first current collecting electrodes intersecting with the target line segments and the number of first interconnect structures in contact with second current collecting electrodes intersecting with the target line segments. If the solar cell is a solar cell with a main grid, the number of all connection lines includes the sum of the number of connection lines corresponding to bus electrodes of two polarities. Next, the number of first interconnect structures intersecting with target line segments located within the target surface also includes the number of first interconnect structures directly in contact with bus electrodes of two polarities intersecting with the target line segments.

[0084] Alternatively, the solar cell provided in the embodiments of the present application may include only a first interconnect structure. Here, the sizes of the different first interconnect structures may be the same or different. For example, as shown in FIGS. 3 and 4, when the solar cell is a solar cell with a main grid, the sizes of the different first interconnect structures 13 may be the same. For example, when the solar cell is a solar cell with a main grid, the sizes of the different first interconnect structures may be different, but the size difference between the different sized first interconnect structures is small (e.g., the ratio of the size of the larger sized first interconnect structure to the size of the smaller sized first interconnect structure in the second direction is greater than 1 and less than 2). Optionally, in the second direction, the target surface may include a central region and an edge region, and the larger sized first interconnect structure may be provided in the edge region, and the smaller sized first interconnect structure may be provided in the central region.

[0085] Alternatively, if the solar cell is a solar cell without a main grid, the solar cell may include a second interconnect structure 14 provided on the target surface, as shown in Figures 2, 13, and 14. Each second interconnect structure 14 is electrically connected to at least one current collecting electrode 12, and the size of the second interconnect structure 14 is smaller than the size of the first interconnect structure 13. At least a portion of the second interconnect structure 14 is located on the same straight line and is collinear with the connecting line. Furthermore, among all the current collecting electrodes 12 located on the same target surface, some current collecting electrodes 12 contact the first interconnect structure 13, and the remaining current collecting electrodes 12 contact the second interconnect structure 14, thereby conducting carriers collected by the current collecting electrodes 12 located on the same target surface via the first interconnect structure 13 and the second interconnect structure 14, respectively. In this case, among all the current collecting electrodes 12 located on the same target surface, some of the current collecting electrodes 12 contact the larger first interconnection structure 13, thereby increasing the contact area between the current collecting electrodes 12 and the intra-string interconnection members. This is beneficial for reducing the contact resistance between the intra-string interconnection members and the current collecting electrodes 12 and for improving the connection strength between the intra-string interconnection members and the current collecting electrodes 12. Next, the remaining current collecting electrodes 12 contact the smaller second interconnection structure 14, which is beneficial for reducing metal composite loss on the target surface side and improving the operating efficiency of the solar cell. For example, the current collecting electrodes 12 in the edge region contact the larger first interconnection structure 13, and the current collecting electrodes 12 in the central region contact the smaller first interconnection structure 13. The second interconnection structure 14 may be a thick portion of the current collecting electrodes 12 or a design that assists electrical connection. In solar cells without a main grid, the size difference between the first interconnection structure 13 and the second interconnection structure 14 is large.

[0086] Specifically, the size of the first interconnect structure described above being larger than the size of the second interconnect structure may mean that, in a first direction, only the length of the first interconnect structure is larger than the length of the second interconnect structure, or that, in a second direction, only the width of the first interconnect structure is larger than the width of the second interconnect structure, or that the length and width of the first interconnect structure are larger than the length and width of the second interconnect structure, respectively.

[0087] It should be noted that in the high-temperature process of solar cell manufacturing, the sintering temperature of the electrodes is generally above 600°C. Due to differences in thermal expansion coefficients during the sintering and cooling processes, both the large-sized first interconnect structure and the small-sized second interconnect structure will experience stress between them and the cell body. If the stress is too great, the cell is likely to crack. Even if the second interconnect structure is small in size, in the case of a solar cell without a main grid, the distribution density of the second interconnect structure on the target surface may be high, which may intensify the formation of hidden cracks within the solar cell without a main grid and lead to the risk of cell cracking. Therefore, the specific sizes of the first and second interconnect structures and the distribution of the second interconnect structure on the target surface can be determined based on the requirements for solar cell yield in actual applications, and are not specifically limited herein.

[0088] Exemplarily, when the solar cell is a solar cell without a main grid, the number of the second interconnection structures intersecting with the target line segment or the vector line segment with an inclination angle of 45° is defined as N7. Here, N7 > (1 / 3)N1, and / or N7 < N1. For example, N7 may be equal to 0.35N1, 0.4N1, 0.5N1, 0.6N1, 0.7N1, 0.8N1 or 0.9N1. In this case, when the number N7 of the second interconnection structures intersecting with the target line segment or the vector line segment with an inclination angle of 45° is greater than (1 / 3)N1, sufficient interconnection strength can be ensured by increasing the distribution density of the second interconnection structures on the target surface. Also, in the high-temperature process in the manufacture of solar cells, the sintering temperature of the electrodes is generally 600 °C or higher. Due to the difference in the coefficient of thermal expansion during the sintering and cooling processes, both the first interconnection structure with a large size and the second interconnection structure with a small size have stress with the battery body, and if the stress is too large, battery cracking is likely to occur. Although the size of the second interconnection structure is small, in the case of a solar cell without a main grid, the distribution density of the second interconnection structures on the target surface may be large, which may exacerbate the formation of hidden cracks inside the solar cell without a main grid and bring the risk of battery cracking. Based on this, when N7 is smaller than N1, it can be ensured that none of the second interconnection structures on at least one connection line on the target surface that can intersect with the target line segment (or the vector line segment with an inclination angle of 45°) are provided on the target line segment (or the vector line segment with an inclination angle of 45°). Thus, after adjacent solar cells are interconnected in the extending direction of the connection line by the in-string interconnection members, none of all the corresponding second interconnection structures intersecting with at least one in-string interconnection member generate sintering stress on the target line segment, the sintering stress formed in the extending direction of the target line segment is reduced, and the increase in the cracking risk of the solar cell due to the large distribution density of the second interconnection structures on the target surface is prevented, ensuring a high yield of the solar cell.

[0089] For example, if the solar cell is a cell without a main grid, the size of the second interconnect structure in the second direction is L1, the size of the first interconnect structure is L2, and 9L1>L2>3L1. In this case, the small size of the second interconnect structure prevents the interconnection area between the solar cell and the intra-string interconnect member from becoming small, thereby increasing the interconnect strength between them. Furthermore, the large size of the second interconnect structure prevents an increase in slurry consumption during the manufacture of the first and second interconnect structures, and prevents an increase in the metal composite and shading area, which is advantageous for reducing the manufacturing cost of the solar cell and for improving the conversion efficiency of the solar cell.

[0090] It should be noted that when the solar cell provided in the embodiment of the present application is a solar cell without a main grid, the thickness and cross-sectional area of ​​the second interconnect structure can be determined according to the actual application scenario, and are not specifically limited herein. Also, when the solar cell is a solar cell without a main grid, the solar cell may not include the second interconnect structure, but may only include the first interconnect structure.

[0091] For example, as shown in FIG. 4 , the solar cell may include bus electrodes 16 disposed on the target surface. Different bus electrodes 16 located on the same target surface extend in the second direction and are spaced apart in the first direction. Each bus electrode 16 is electrically connected to a collecting electrode 12 of the same polarity as itself and contacts at least one first interconnect structure 13. Different bus electrodes 16 correspond one-to-one to different connecting lines. In this case, the solar cell provided in the embodiment of the present application is a “solar cell with a main grid.” Based on this, in actual application processes, the collecting electrodes 12 generally have a small line width to reduce their own light-blocking area, which makes the collecting electrodes 12 relatively prone to breakage. The presence of the bus electrodes 16 allows carriers collected by the portions of the collecting electrodes 12 on both sides of the break to be transmitted to the connected bus electrodes 16, respectively, thereby improving current collection capability and reducing power loss.

[0092] Here, in this case, if the solar cell has a double-sided contact substrate structure, the bus electrodes located on the same target surface are electrically connected to all of the collecting electrodes. If the solar cell has a back-contact substrate structure, the collecting electrodes include first and second collecting electrodes of opposite polarity, where the first and second collecting electrodes are alternately spaced apart in the second direction. The bus electrodes include first and second bus electrodes of opposite polarity, where the first and second bus electrodes are alternately spaced apart in the first direction. The opposite-polarity bus electrodes and collecting electrodes are insulated from each other. Specifically, the bus electrodes and collecting electrodes may both be continuous electrodes, and in this case, the bus electrodes may be electrically insulated from the collecting electrodes of the opposite polarity by an insulating material such as an insulating paste. Alternatively, the collecting electrodes may be discontinuous collecting electrodes, and the bus electrodes may be continuous bus electrodes, where the bus electrodes are electrically insulated from the collecting electrodes of the opposite polarity by interruptions in the discontinuous collecting electrodes. Alternatively, the bus electrode may be a discontinuous bus electrode and the collecting electrode may be a continuous collecting electrode, and a collecting electrode may be electrically isolated from a bus electrode of opposite polarity by an interruption in the discontinuous bus electrode. Here, the positive electrode of the back-contact type substrate structure may include the first collecting electrode and the first bus electrode, and the negative electrode of the back-contact type substrate structure may include the second collecting electrode and the second bus electrode, or the negative electrode of the back-contact type substrate structure may include the first collecting electrode and the first bus electrode, and the positive electrode of the back-contact type substrate structure may include the second collecting electrode and the second bus electrode.

[0093] It should be noted that the current collecting electrode included in the positive electrode has a polarity opposite to that of the current collecting electrode included in the negative electrode and to that of the first interconnect structure (or second interconnect structure) electrically connected to the current collecting electrode included in the negative electrode. Also, if the solar cell is a "solar cell with a main grid," the bus electrode included in the positive electrode has a polarity opposite to that of the current collecting electrode included in the negative electrode, to that of the bus electrode included in the negative electrode, and to that of the first interconnect structure electrically connected to the bus electrode included in the negative electrode.

[0094] Furthermore, the embodiments of the present application do not specifically limit the number and shape of collecting electrodes included in the solar cell, or the distance between adjacent collecting electrodes. Specifically, the distances between different pairs of collecting electrodes may be the same or different. It is understood that when the size of the collecting electrodes is fixed, the carrier collection range corresponding to the collecting electrodes is constant. In this case, as shown in Figures 2 and 4, the distances between pairs of different collecting electrodes 12 are equal, thereby uniformly distributing the different collecting electrodes 12 in the second direction. The distance between two adjacent collecting electrodes 12 of the same polarity in at least one pair of collecting electrodes 12 is greater than the distance between two adjacent collecting electrodes 12 of the same polarity in another pair of collecting electrodes 12, which is advantageous in preventing at least one collecting electrode 12 in the pair from having difficulty quickly collecting and extracting carriers within a large separation range, and ensuring a low carrier recombination rate on the target surface side. Furthermore, since the distance between two adjacent collecting electrodes 12 of the same polarity in at least one pair of collecting electrodes 12 is smaller than the distance between two adjacent collecting electrodes 12 of the same polarity in another pair of collecting electrodes 12, the distribution density of the collecting electrodes 12 in a portion of the target surface side increases, which is advantageous in preventing an increase in the light-blocking area of ​​the collecting electrodes 12 and in the metal composite loss between the collecting electrodes 12 and the battery body 11, and is advantageous in improving the photoelectric conversion efficiency of the solar cell.

[0095] Next, when the solar cell provided in the embodiments of the present application includes bus electrodes, the number and shape of the bus electrodes and the distance between adjacent bus electrodes in the embodiments of the present application can be determined according to the requirements for the number and shape of connecting lines and the distance between adjacent connecting lines in actual applications, and no specific limitations are provided herein.

[0096] The specific directions of the first and second directions can be determined according to actual needs and can be applied to the solar cell provided in the embodiments of the present application. For example, if the shape of the target surface is rectangular, the rectangle has first and second sides that are alternately distributed. The first direction can be parallel to the first side of the rectangle, and in this case, the second direction can be parallel to the second side of the rectangle.

[0097] In an actual application process, as shown in FIGS. 2 and 12, if the solar cell is a solar cell without a main grid, the current collecting electrode 12 in contact with the first interconnect structure 13 is defined as the connection electrode 15. The distance between two adjacent connection electrodes 15 in the second direction is defined as D1. At least one connection electrode 15 located in the edge region contacts multiple first interconnect structures 13, and different first interconnect structures 13 electrically contacting the connection electrodes 15 are spaced apart in the first direction. The distance between the geometric centers of two adjacent first interconnect structures 13 in contact with the connection electrode 15 is defined as D2. In this case, it can be seen that the arrangement of different connection electrodes 15 on the target surface is different. Accordingly, the arrangement positions on the target surface of the first interconnect structures 13 electrically contacting different connection electrodes 15 also differ. The arrangement positions of the first interconnect structures 13 on the target surface affect the magnitude of the above-mentioned N2 value. 12, a smaller second interconnect structure 14 may be distributed between the two connection electrodes 15, and the second interconnect structure 14 may be electrically connected to the current collecting electrode 12 between the two connection electrodes 15. In this case, among all the current collecting electrodes 12 located on the same target surface, which part of the current collecting electrodes 12 is in electrical contact with the first interconnect structure 13 and which part of the current collecting electrodes 12 is in electrical contact with the second interconnect structure 14 can be determined according to the size requirement of N2 in actual application scenarios, and is not specifically limited here.

[0098] For example, if the solar cell is a solar cell without a main grid, the first interconnect structures at the two ends located in the edge regions are in electrical contact with the collecting electrodes located in the edge regions, and the second interconnect structure located in the central region is in electrical contact with the collecting electrodes located in the central region, in which case D1 is the distance between two collecting electrodes that are in contact with the first interconnect structures located at the ends and adjacent to each other in the second direction, and D2 is the distance between the geometric centers of two first interconnect structures that are adjacent to each other in the first direction.

[0099] Next, as shown in Figures 4 and 7, when the solar cell is a solar cell having a main grid, the bus electrode 16 is defined as a connection electrode 15. Furthermore, the distance between two adjacent connection electrodes 15 in the first direction is defined as D1. At least one connection electrode 15 contacts multiple first interconnection structures 13, and different first interconnection structures 13 in contact with the same connection electrode 15 are spaced apart in the second direction. The distance between the geometric centers of two adjacent first interconnection structures 13 in contact with the same connection electrode 15 is defined as D2.

[0100] For example, if the solar cell is a solar cell with a main grid, the first interconnect structures at the two ends located in the edge regions are relatively large in size and are in electrical contact with the current collecting electrodes located in the edge regions, and the first interconnect structure located in the central region is relatively small in size and is in electrical contact with the current collecting electrodes located in the central region, in which case D1 is the distance between two bus electrodes adjacent in the first direction, and D2 is the distance between the geometric centers of two first interconnect structures that are in contact with the same bus electrode and are adjacent in the first direction.

[0101] In this case, in the solar cell, the first interconnection structures that contact different connection electrodes and are in the same layer are aligned in the first direction, thereby reducing the connection difficulty of an automatic interconnection device such as a stringer that realizes the interconnection of adjacent solar cells. Based on this, as shown in Figures 7 and 12, when D2 corresponding to each pair of first interconnection structures 13 is equal to D1, the inclination angles of the lines connecting the first interconnection structure 13 of a given layer provided on each connection electrode 15 and the first interconnection structure 13 of an adjacent layer provided on the adjacent connection electrode 15 are all equal to 45°, and therefore N3 corresponding to each vector line segment with an inclination angle of 45° is all equal to N4. When D2 corresponding to at least one pair of first interconnect structures is not equal to D1, the inclination angle of the line connecting the first interconnect structure of a certain layer provided on a certain connection electrode and the first interconnect structure of an adjacent layer provided on an adjacent connection electrode is not equal to 45°, and therefore the inclination angle of the interconnect stress zone corresponding to the pair of first interconnect structures is not equal to 45°, which is advantageous for shortening the length of the interconnect stress zone formed in the extension direction of the vector line segment with an inclination angle of 45° and is also advantageous for shortening the length of the interconnect stress zone formed in the cleavage plane direction, which is advantageous for reducing the risk of cracking problems occurring after the solar cell is subjected to external force due to the long interconnect stress zone, and improving the structural reliability of the solar module formed based on the solar cell.

[0102] Specifically, for a given length of the connecting electrodes, the greater the ratio of D2 to D1 corresponding to at least one pair of first interconnect structures, the greater the distance between two adjacent first interconnect structures contacted by the same connecting electrode. Conversely, the smaller the ratio of D2 to D1 corresponding to at least one pair of first interconnect structures, the smaller the distance between two adjacent first interconnect structures contacted by the same connecting electrode. However, the closer this ratio is to 1, the closer the inclination angle of the connecting line between the pair of first interconnect structures will be to 45°, i.e., the closer it will be to the extension direction of the cleavage plane. In this case, when D2 corresponding to at least one pair of first interconnect structures is not equal to D1, the specific ratio of D2 to D1 can be determined based at least on the inclination angle of the interconnect stress zone formed after interconnection in actual application and the transmission loss of carriers in the bus electrode, and is not specifically limited herein.

[0103] For example, when the solar cell has a main grid, the ratio of D2 to D1 corresponding to at least one pair of first interconnect structures may be 1 or more and 1.7 or less. For example, the ratio of D2 to D1 corresponding to at least one pair of first interconnect structures may be 1, 1.06, 1.1, 1.12, 1.14, 1.16, 1.2, 1.3, 1.4, 1.5, 1.6, or 1.7. In this case, setting the ratio of D2 to D1 corresponding to at least one pair of first interconnect structures within the above range is advantageous in preventing the extension direction of the interconnect stress zone corresponding to at least one pair of first interconnect structures from approaching the extension direction of the cleavage plane, thereby ensuring the length of the interconnect stress zone formed in the cleavage plane direction can be shortened. Furthermore, a large ratio also increases the distance between two adjacent first interconnect structures contacted by the same connecting electrode, which is advantageous in preventing increased carrier transmission loss in the connecting electrode and is advantageous in improving the operating efficiency of the solar cell.

[0104] Exemplarily, when the solar cell is a solar cell without a main grid, the ratio of D1 to D2 corresponding to the at least one pair of first interconnect structures may be greater than or equal to 6 and less than or equal to 12. For example, the ratio of D1 to D2 corresponding to the at least one pair of first interconnect structures may be 6, 7, 8, 9, 10, 11, 12, etc.

[0105] In actual application, the distance between two adjacent first interconnection structures among all first interconnection structures contacting the same connecting line may be the same or different. In the second direction, the distance between the geometric centers of two adjacent first interconnection structures among all first interconnection structures contacting the same connecting line affects the number of pairs of current collecting electrodes provided between the geometric centers of the two adjacent first interconnection structures. Here, each pair of current collecting electrodes has the same polarity as the corresponding first interconnection structure and includes two adjacent current collecting electrodes in the second direction. Specifically, if the distances between different pairs of current collecting electrodes are equal, and the distances between the geometric centers of the two adjacent first interconnection structures are equal, the number of pairs of current collecting electrodes between the geometric centers of the two adjacent first interconnection structures is also equal. Conversely, if the distances between the geometric centers of the two adjacent first interconnection structures are unequal, the number of pairs of current collecting electrodes between the geometric centers of the two adjacent first interconnection structures is also unequal. In this case, by adjusting the number of collecting electrodes located between the geometric centers of two adjacent first interconnect structures, the distance between the geometric centers of two adjacent first interconnect structures can be controlled, and further the extension direction of the interconnect stress zone formed by the two adjacent first interconnect structures after interconnection can be adjusted and controlled.

[0106] In a second aspect, the present embodiment provides another solar cell. Specifically, the solar cell provided in the present embodiment may be any cell that can convert solar energy into electrical energy.

[0107] Regarding the arrangement positions of the positive and negative electrodes, the solar cell provided in the examples of the present application may have a double-sided contact substrate structure, i.e., one of the positive and negative electrodes of the solar cell is disposed on the front side of the solar cell and the other is disposed on the back side, or the solar cell provided in the examples of the present application may have a back-contact substrate structure, i.e., both the positive and negative electrodes of the solar cell are disposed on the back side of the solar cell.

[0108] Regarding the specific electrode structures of the positive and negative electrodes, the solar cell provided in the examples of the present application may be a "solar cell with a main grid," in which the solar cell includes not only collecting electrodes but also bus electrodes, with different bus electrodes corresponding one-to-one to different connecting lines. Alternatively, the solar cell provided in the examples of the present application may be a "solar cell without a main grid," in which the solar cell without a main grid does not have the bus electrodes of the solar cell with a main grid. Specifically, the electrode structure of a solar cell without a main grid may include only collecting electrodes, or may include collecting electrodes and bus electrode segments that serve as current collectors (the bus electrode segments may be electrically connected to first interconnect structures located at the edges in the second direction and extend toward the edges of the cell body in the second direction). The specific shape of the bus electrode segments is not limited and may be, for example, linear, curved, or curved.

[0109] Specifically, as shown in FIGS. 1 and 3, the solar cell includes a cell body 11, current collecting electrodes 12, and first interconnect structures 13. The cell body 11 has opposing first and second surfaces. At least one of the first and second surfaces is a target surface. The current collecting electrodes 12 are disposed on the target surface. Different current collecting electrodes 12 located on the same target surface all extend in a first direction and are spaced apart in a second direction. The first direction is perpendicular to the second direction. The first interconnect structures 13 are formed in an array on the target surface. Each first interconnect structure 13 is electrically connected to at least one current collecting electrode 12. At least some regions of different first interconnect structures 13 spaced apart in the second direction are located on the same connecting line, and different connecting lines are spaced apart in the first direction. The number of connecting lines located within the same target surface is N1, and the number of first interconnect structures 13 that intersect with target line segments located within the target surface is N2, where N1>N2, and the target line segments are diagonal lines of the target surface and intersect with all of the connecting lines. It should be noted that N1>N2 is applicable to solar cells without a main grid, solar cells with a main grid, back-contact substrate structures, and double-sided contact substrate structures.

[0110] Specifically, the number N1 of connecting lines refers to the number of connecting lines in each divided battery cell (generally, the number of connecting lines in two divided battery cells is the same), and the number N1 of connecting lines is a positive integer greater than or equal to 1. The number N2 of first interconnect structures intersecting with target line segments located within the target surface is an integer greater than or equal to 0. The specific values ​​of the number N1 of connecting lines and the number N2 of first interconnect structures intersecting with target line segments located within the target surface can be determined according to actual application scenarios, and are not specifically limited herein.

[0111] When the above technical solution is adopted, the target line segment is the diagonal of the target surface and intersects with any of the connection lines. Also, when N2 < N1, it can be ensured that none of the first interconnect structures where each of at least one connection line in the target surface that can intersect the target line segment is in electrical contact is provided on the target line segment. Thus, after adjacent solar cells are interconnected in the extending direction of the connection lines by the in-string interconnecting members, none of all the corresponding first interconnect structures that are in electrical contact with each of at least one in-string interconnecting member generates an interconnect stress on the target line segment, and the interconnect stress formed in the extending direction of the target line segment is reduced. In this case, the direction of the diagonal in the surface of the semiconductor wafer used in the manufacture of the solar cell is substantially parallel to the cleavage plane. The cleavage plane is a plane having the property that a mineral crystal can be broken along a strictly certain crystallization direction by an external force and split into a smooth surface. Therefore, corresponding to the silicon wafer, when a single-crystal silicon crystal bar is wire-cut, a substantially rectangular silicon wafer is formed. The cleavage plane intersects the silicon wafer surface and is not parallel to the edge of the silicon wafer. There are innumerable cleavage planes parallel to each other in the crystal bar, forming innumerable target line segments parallel to the silicon wafer surface. Among them, the target line segment corresponding to the diagonal of the silicon wafer is the longest and has a greater stress problem. Therefore, when the target line segment is the diagonal of the target surface, it can be understood that the extending direction of the target line segment is substantially parallel to the direction of the cleavage plane of the battery body. At this time, the reduction of the interconnect stress formed in the extending direction of the target line segment corresponds to the reduction of the interconnect stress formed in the cleavage plane direction. Since the interconnect stress is large, the risk of cracking problems occurring after the solar cell receives an external force is reduced, and the structural reliability of the solar module formed based on the solar cell is improved.

[0112] It should be noted that, from the above, it can be seen that the solar cell provided in the first embodiment of the present invention is a half-cut solar cell. The solar cell provided in the second embodiment of the present invention is a whole solar cell. In this case, the solar cell provided in the first embodiment of the present invention may be considered to be obtained by cutting the solar cell provided in the second embodiment of the present invention in half. Based on this, the structure and materials of the cell body, and the distribution of the current collecting electrodes and the first interconnect structure in the solar cell provided in the second embodiment of the present invention can be referred to above, and detailed description thereof will be omitted here.

[0113] In the following, only the differences between the solar cell provided in the second embodiment of the present invention and the solar cell provided in the first embodiment of the present invention will be described.

[0114] Specifically, in the solar cell provided in the second aspect of the present embodiment, the specific distribution positions of the target line segments within the target surface can be determined according to the distribution of the intersection lines between the cleavage plane of the cell body and the target surface and the shape of the target surface, and are not specifically limited herein. Here, if the apex angle of the target surface is a sharp angle, the target line segments may be line segments connecting the diagonal end points of the target surface. If the apex angle of the target surface is a chamfer with a smooth transition, etc., the target line segments may be line segments connecting the end points of the diagonal extension lines of the target surface.

[0115] In actual application processes, the number of connecting lines intersecting the target line segments is defined as N3, as shown in FIGS. 1 and 3. Based on this, N3 > N2. In this case, since the target line segments intersect only with the extension of at least one connecting line, interconnect stress is not generated at the intersections. This ensures that the interconnect stress formed in the extension direction of the target line segments can be reduced. This is advantageous for shortening the length of the interconnect stress zone formed in the cleavage plane direction. The long interconnect stress zone further reduces the risk of cracking after the solar cell is subjected to external force, thereby improving the structural reliability of solar modules formed based on the solar cell. Next, the number of connecting lines on the target surface, N1, is equal to or greater than the number of connecting lines intersecting the target line segments, N3. Here, if a portion of the first interconnect structure included in the solar cell is located at the edge of the target surface in the first direction and the connecting line does not intersect the target line segment, N1 may be greater than N3. Alternatively, if the four vertex angles of the target surface are vertex angles with large chamfers, some of the connecting lines may pass through the chamfers, in which case N1 may be greater than N3. If all of the first interconnect structures included in the solar cell are located at the center of the target surface in the first direction, N1 may be equal to N3. Alternatively, if the four apex angles of the target surface are apex angles without chamfers or with small chamfers, none of the connecting lines may pass through the chamfers, in which case N1 may be equal to N3.

[0116] Next, the distribution of the current collecting electrodes among different first interconnect structures and the distribution between the first interconnect structures located at the edges in the second direction and the boundary of the battery body can be determined according to the requirements for the magnitudes of N1 and N2 in actual application scenarios, and are not specifically limited here.

[0117] 1 and 3, the solar cell may include M divided battery cells spaced apart in the second direction, where M is a positive integer greater than or equal to 1. In the same divided battery cell, the geometric centers of two first interconnect structures 13 located at the edges in the second direction are symmetrically arranged with respect to the center line of the divided battery cell in the second direction. In this case, for the same divided battery cell, the geometric centers of the two first interconnection structures 13 located at the edges in the second direction are arranged symmetrically with respect to the centerline of the divided battery cell in the second direction, thereby allowing an automatic interconnection device such as a stringer to interconnect different divided battery cells at the same starting position. This prevents misalignment between intra-string interconnection members such as solder ribbons and the first interconnection structures 13 provided on the battery body 11 due to differences in the starting positions corresponding to different divided battery cells, and further prevents carriers in connection lines corresponding to first interconnection structures 13 that are not electrically connected to the intra-string interconnection members from being unable to be guided through the intra-string interconnection members, resulting in power loss or the corresponding first interconnection structures 13 becoming a load and reducing the operating efficiency of the solar cell. This ensures good operating performance of solar modules formed based on the solar cells provided in the embodiments of the present application. Naturally, for the same divided battery cell, the number of pairs of current collecting electrodes 12 between each of the geometric centers of the two first interconnection structures 13 located at the edges in the second direction and the edge of the divided battery cell does not have to be arranged symmetrically in order to reduce manufacturing requirements. It should be noted that in the same divided battery cell, the geometric centers of the two first interconnect structures 13 located at the edges in the second direction are arranged symmetrically with respect to the center line of the divided battery cell in the second direction, which can be applied to solar cells without a main grid, solar cells with a main grid, back-contact type substrate structures, and double-sided contact type substrate structures.

[0118] For example, when the number of first interconnection structures located on the same connection line is odd, in the second direction in the same divided battery cell, the remaining first interconnection structures, except for the first interconnection structure located at the center and two other first interconnection structures adjacent to the first interconnection structure located at the center, are edge first interconnection structures. The number of pairs of current collecting electrodes located between the geometric centers of two adjacent edge first interconnection structures is symmetrically arranged with respect to the central axis of the first interconnection structure located at the center. Alternatively, when the number of first interconnection structures located on the same connection line is even, in the same divided battery cell, the remaining first interconnection structures, except for the pair of first interconnection structures located at the center, are edge first interconnection structures. The number of pairs of current collecting electrodes 12 located between the geometric centers of two adjacent edge first interconnection structures is symmetrically arranged with respect to the central axis of the pair of first interconnection structures located at the center.

[0119] When the above technical solution is adopted, if the number of first interconnection structures contacted by the same connecting line for the same divided battery cell is odd, the remaining first interconnection structures in the same divided battery cell in the second direction, excluding the centrally located first interconnection structure and the other two first interconnection structures adjacent to the centrally located first interconnection structure, are defined as edge first interconnection structures. In this case, if the pairs of current collecting electrodes located between the geometric centers of the two adjacent edge first interconnection structures are arranged symmetrically with respect to the central axis of the centrally located first interconnection structure, it is advantageous to arrange different current collecting electrodes as uniformly as possible between the geometric centers of the two adjacent first interconnection structures in the second direction, thereby facilitating lap joints between corresponding current collecting electrodes and first interconnection structures, maximizing current collection, facilitating debugging of the interconnection device that interconnects adjacent solar cells, and preventing misalignment of the interconnections. Furthermore, when the number of pairs of first interconnection structures located on the same connection line is an even number, in the same divided battery cell in the second direction, the remaining first interconnection structures, except for a pair of first interconnection structures located in the center, are edge first interconnection structures. The beneficial effect of the number of pairs of current collecting electrodes located between the geometric centers of two adjacent edge first interconnection structures being symmetrically arranged with respect to the central axis of the pair of first interconnection structures located in the center can be seen from the above description, and a detailed description thereof will be omitted here.

[0120] In the following, we will use an example in which the number of first interconnection structures contacting the same connection line is seven and 92 current collecting electrodes of the same polarity (91 pairs of current collecting electrodes) are provided in the same divided battery cell. When the number of first interconnection structures contacting the same connection line is odd, the number of pairs of current collecting electrodes located between the geometric centers of two adjacent first interconnection structures in the same divided battery cell in the second direction will be described. Different first interconnection structures that cross the same connection line are arranged in order from top to bottom. In this case, the central first interconnection structure is the fourth first interconnection structure. In the same divided battery cell, the first to second first interconnection structures and the sixth to seventh first interconnection structures are edge first interconnection structures. In this case, the number of pairs of current collecting electrodes between the geometric centers of the first and second first interconnection structures is 12 pairs. The number of pairs of current collecting electrodes between the geometric centers of the second and third first interconnection structures is 11 pairs. The number of pairs of current collecting electrodes between the geometric centers of the fifth first interconnect structure and the sixth first interconnect structure is 11. The number of pairs of current collecting electrodes between the geometric centers of the sixth first interconnect structure and the seventh first interconnect structure is 12. In the second direction, the number of pairs of current collecting electrodes between the geometric centers of the first interconnect structures located at the edges (i.e., the first first interconnect structure and the seventh first interconnect structure) and the edges of the battery body is both 11.

[0121] The following describes the number of pairs of current collecting electrodes located between the geometric centers of two adjacent first interconnection structures in the same divided battery cell in the second direction when the number of first interconnection structures contacting the same connecting line is an even number, using the structures shown in FIGS. 1 and 3 as an example. Here, as shown in FIGS. 1 and 3, the number of first interconnection structures 13 contacting the same connecting line is six, and 27 current collecting electrodes 12 of the same polarity (26 pairs of current collecting electrodes 12) are provided in the same divided battery cell. Different first interconnection structures 13 that intersect with the same connecting line are arranged in order from top to bottom. The central pair of first interconnection structures 13 is the third first interconnection structure 13 and the fourth first interconnection structure 13. The first, second, fifth, and sixth first interconnection structures 13 are all edge first interconnection structures. Specifically, the number of pairs of current collecting electrodes 12 between the geometric centers of the first first interconnect structure 13 and the second first interconnect structure 13 is four pairs. The number of pairs of current collecting electrodes 12 between the geometric centers of the fifth first interconnect structure 13 and the sixth first interconnect structure 13 is also four pairs. In the second direction, the number of pairs of current collecting electrodes 12 between the geometric centers of the first interconnect structures 13 located at the edges (i.e., the first first interconnect structure 13 and the sixth first interconnect structure 13) and the edge of the battery body 11 is three pairs.

[0122] In an actual application process, the number of first interconnection structures contacting the same connection line is defined as a, the length of the portion of the battery body corresponding to each divided battery cell in the second direction is defined as b, and the distance between adjacent current collecting electrodes of the same polarity is defined as c. The number of pairs of current collecting electrodes that can be arranged in the divided battery cell, d1, can be obtained by dividing b by c. The average number of pairs of current collecting electrodes that can be arranged within the distance between the geometric centers of two adjacent first interconnection structures corresponding to the same connection line or the geometric centers of first interconnection structures located on an edge in the second direction and the edge of the battery body, d2, can be obtained by dividing d1 by (a + 1). Here, when d2 is an integer, the distance between the geometric centers of different pairs of first interconnection structures contacting the same connection line (the first interconnection structures of each pair are two adjacent first interconnection structures that cross the same connection line) is equal. If d2 has a remainder, the distance between the geometric centers of at least one pair of first interconnect structures that contact the same connecting line is not equal to the distance between the geometric centers of the remaining pairs of first interconnect structures. Specifically, if d2 has a remainder, the actual number of pairs of current collecting electrodes located between the geometric centers of each pair of first interconnect structures can be set according to the above-mentioned symmetry rules, and detailed description thereof will be omitted here.

[0123] For example, when the solar cell has a back-contact substrate structure and includes at least two divided battery cells spaced apart in the second direction, a scribe line is formed between two adjacent divided battery cells. Furthermore, the opposite-polarity current collecting electrodes of the two adjacent divided battery cells are arranged symmetrically with respect to the scribe line, and / or the opposite-polarity first interconnect structures of the two adjacent divided battery cells are arranged symmetrically with respect to the scribe line, and / or the opposite-polarity bus electrodes of the two adjacent divided battery cells are arranged symmetrically with respect to the scribe line. In this case, at least one of the opposite-polarity current collecting electrodes, the first interconnect structures, and the bus electrodes of the two adjacent divided battery cells is arranged symmetrically with respect to the scribe line, which facilitates interconnection between the two adjacent divided battery cells, prevents misalignment, improves the interconnection yield, and reduces the difficulty of interconnection. It should be noted that the fact that the opposite polarity collecting electrodes (and / or first interconnection structures, and / or bus electrodes) of the two adjacent divided battery cells are arranged symmetrically with respect to the scribe line as described above also applies to the back-contact substrate structures of both solar cells without a main grid and solar cells with a main grid.

[0124] For example, when the target line segment is a diagonal line of the target surface, at least two of all first interconnect structures intersecting with the target line segment may be distributed symmetrically around the geometric center of the target surface, and the polarities of the symmetrically distributed first interconnect structures may be the same. In this case, it is advantageous for the first interconnect structures intersecting with the target line segment to be uniformly distributed, and it is advantageous for the interconnect stress generated by the first interconnect structures on the target line segment after interconnection to be uniformly distributed around the geometric center of the target surface. This prevents the interconnect stress from concentrating in a certain region on the target line segment due to the uneven distribution of the first interconnect structures on the target line segment, which increases the risk of the cell body cracking in that region, and further improves the structural reliability of the solar module formed based on the solar cell.

[0125] Alternatively, as shown in Figures 8 and 10, when the target line segment is a diagonal line of the target surface, among all the first interconnect structures 13 that intersect with the target line segment, at least two first interconnect structures 13 may be distributed symmetrically around the geometric center of the target surface, and the polarities of the symmetrically distributed first interconnect structures 13 may be opposite.

[0126] For example, if a solar cell includes two divided battery cells spaced apart in the second direction, the N2 values ​​corresponding to the two divided battery cells are equal. As shown in Fig. 10, in the same divided battery cell, the polarities of the two bus electrodes 16 located on the outside in the first direction are opposite. The polarities of the two bus electrodes 16 located opposite to each other and belonging to different divided battery cells and located on the outside in the first direction are opposite. This is advantageous in improving symmetry between the different first interconnection structures 13 with opposite polarities located on the same target surface and in reducing the difficulty of interconnecting adjacent solar cells using an automatic interconnection device such as a stringer.

[0127] It should be noted that when the aforementioned solar cell includes two divided battery cells spaced apart in the second direction, the equality of N2 corresponding to the two divided battery cells also applies to the back-contact substrate structures of both solar cells without a main grid and solar cells with a main grid.

[0128] For example, if a solar cell includes two divided battery cells spaced apart in the second direction, the N2 values ​​corresponding to the two divided battery cells are not equal. In the same divided battery cell, the two bus electrodes located on the outside in the first direction have the same polarity. The two bus electrodes located opposite to each other and belonging to different divided battery cells have opposite polarities. This provides another possible implementation for the solar cell provided in the embodiments of the present application, improving the applicability of the solar cell provided in the embodiments of the present application in different application scenarios.

[0129] For example, when the polarities of two bus electrodes located on the outside in the first direction are opposite, at least two of all first interconnection structures intersecting the target line segment may be equidistant from the center line of the target surface in the second direction and may have the same polarity, which is advantageous for improving the distribution uniformity between first interconnection structures of different polarities located on the same target surface and for reducing the difficulty of interconnecting adjacent solar cells using an automatic interconnection device such as a stringer.

[0130] Alternatively, as shown in FIG. 11, when the polarities of the two outer bus electrodes 16 are opposite in the first direction, at least two of all first interconnect structures 13 that intersect with the target line segment may be at equal distances from the center line of the target surface in the second direction and may have opposite polarities.

[0131] Exemplarily, when the solar cell is a solar cell without a main grid, the solar cell may include a second interconnect structure provided on the target surface. Each second interconnect structure is electrically connected to at least one current collecting electrode, and the size of the second interconnect structure is smaller than the size of the first interconnect structure. At least a part of the region of the second interconnect structure is located on the same straight line and is collinear with the connection line. Among all the current collecting electrodes located on the same target surface, some current collecting electrodes are in contact with the first interconnect structure. Exemplarily, the first interconnect structure is located in two edge regions in the second direction of the solar cell without a main grid, and the remaining current collecting electrodes are in contact with the second interconnect structure. Exemplarily, the second interconnect structure is located in the central region in the second direction of the cell without a main grid. The number of the second interconnect structures intersecting the target line segment is N8, where N8 > (1 / 2)N1 and / or N8 < 1.5N1. For example, N8 may be equal to 0.6N1, 0.7N1, 0.8N1, 0.9N1, N1, 1.1N1, 1.2N1, 1.3N1 or 1.4N1, etc. The application principle of the beneficial effect in this case can refer to the application principle of the beneficial effect that N7 > (1 / 3)N1 and N7 < N1 described above, and the detailed description is omitted here.

[0132] In a third aspect, an embodiment of the present application provides a solar module including a solar cell and an in-string interconnecting member for serially connecting two adjacent solar cells. The solar cell is the solar cell provided in the first aspect and its various implementation forms, or the solar cell provided in the second aspect and its various implementation forms. Each in-string interconnecting member is in electrical contact with the corresponding first interconnect structure.

[0133] Here, it can be understood that when the solar cell is a double-sided contact type substrate structure, a solar cell without a main grid or a solar cell having a main grid, the in-string interconnecting member may be located on different surfaces of two adjacent solar cells. Or, when the solar cell is a back contact type substrate structure, the in-string interconnecting member is located on the same surface of two adjacent solar cells.

[0134] The beneficial effects of the third aspect of the present application and its various implementation forms may refer to the analysis of the beneficial effects of the first aspect and its various implementation forms, or may refer to the analysis of the beneficial effects of the second aspect and its various implementation forms, and detailed description thereof will be omitted here.

[0135] A fourth aspect, an embodiment of the present application, provides another solar module including solar cells and an intra-string interconnection member connecting two adjacent solar cells in series. As shown in FIGS. 2 and 4 , the solar cell includes a cell body 11, a current collecting electrode 12, and a first interconnection structure 13. The cell body 11 has opposing first and second surfaces. At least one of the first and second surfaces is a target surface. The current collecting electrodes 12 are provided on the target surface. Different current collecting electrodes 12 located on the same target surface all extend in a first direction and are spaced apart in a second direction. The first direction is perpendicular to the second direction. Each first interconnection structure 13 is electrically connected to at least one current collecting electrode 12. Each intra-string interconnection member is in electrical contact with a corresponding first interconnection structure 13. The number of first interconnect structures 13 intersecting with target line segments located within the target surface is N2, where the target line segments are line segments connecting the midpoint of the longer of two edges extending in a first direction of the target surface and distributed opposite to each other to the apex end point of the shorter of the two edges. The number of intra-string interconnect members located on the same target surface is N5. The number of first interconnect structures 13 intersecting with at least one vector line segment with the same 45° inclination angle is N4. The number of intra-string interconnect members intersecting with the same 45° inclination vector line segment is N6, where N2<(1 / 2)N5 or N6>N4.

[0136] In a possible implementation, N2 corresponding to at least two solar cells in the same solar module are equal.

[0137] The beneficial effects of the fourth aspect of the present application and its various implementation forms may be referred to the analysis of the beneficial effects of the first aspect and its various implementation forms, and detailed description thereof will be omitted here.

[0138] Although the above description does not provide a detailed description of the technical details of each layer, such as the structure and etching of each layer, those skilled in the art should understand that layers, regions, etc. of desired shapes can be formed using various technical means. Furthermore, those skilled in the art can also design methods that are not completely identical to the methods described above to form similar structures. Furthermore, although each embodiment has been described above, this does not mean that the means in each embodiment cannot be advantageously combined.

[0139] Although the embodiments of the present application have been described above, these embodiments are merely for illustrative purposes and do not limit the scope of the present application. The scope of the present application is limited by the appended claims and their equivalents. Those skilled in the art can make various substitutions and modifications without departing from the scope of the present application, and all of these substitutions and modifications are intended to be included in the scope of the present application. [Explanation of symbols]

[0140] 11 Battery body 12 Current collecting electrode 13 First interconnect structure 14 Second interconnect structure 15 Connecting electrode 16 Bus electrode

Claims

1. a battery body having a first surface and a second surface facing each other, at least one of the first surface and the second surface being a target surface; current collecting electrodes provided on the target surface, wherein different current collecting electrodes located on the same target surface all extend in a first direction and are spaced apart in a second direction, and the first direction is perpendicular to the second direction; an array of first interconnection structures formed on the target surface, each of the first interconnection structures being electrically connected to at least one of the current collecting electrodes, at least some regions of different first interconnection structures spaced apart in the second direction being located on the same connection line, and the different connection lines being spaced apart in the first direction; A solar cell, wherein the number of the connection lines located within the same target surface is N1, the number of the first interconnect structures intersecting with target line segments located within the target surface is N2, where N2 < (1 / 2)N1, and the target line segments are line segments connecting the midpoint of the longer of two edges extending in the first direction of the target surface and distributed opposite to each other, to the apex end point corresponding to the shorter of the two edges, or the number of the connection lines intersecting with a vector line segment with a tilt angle of 45° is N3, and the number of the first interconnect structures intersecting with at least one same vector line segment with a tilt angle of 45° is N4, where N3 > N4.

2. The thickness of the battery body is H1, the thickness of the first interconnect structure is H2, and the ratio of H2 to H1 is 0.005 or more and 0.1 or less; and / or 2. The solar cell of claim 1, wherein the cross-sectional area of ​​the cell body is S1, the cross-sectional area of ​​the first interconnect structure is S2, and the ratio of S2 to S1 is 0.0003 or more and 0.02 or less.

3. The solar cell of claim 1 , wherein N2 is equal to 0.

4. a distance between the geometric center of the first interconnect structure intersecting the target line segment or the vector line segment with the 45° tilt angle and the center line of the solar cell in the second direction is D3; 2. The solar cell of claim 1, wherein the distance between the geometric center of the first interconnect structure intersecting the target line segment or the vector line segment with a tilt angle of 45° and the edge of the solar cell in the second direction is D4, and D3 > D4 corresponds to at least one of the first interconnect structures.

5. 2. The solar cell of claim 1, wherein the solar cell is a solar cell without a main grid, and in the second direction, the target surface includes a central region and an edge region, and at least a portion of the collecting electrode located in the edge region is in electrical contact with the first interconnect structure.

6. 6. The solar cell of claim 5, wherein the solar cell has a back-contact substrate structure, the collecting electrodes include first and second collecting electrodes of opposite polarity, the first and second collecting electrodes are alternately spaced apart in the second direction, at least a portion of the first collecting electrode on the edge region is in electrical contact with the first interconnect structure, and at least a portion of the second collecting electrode on the edge region is in electrical contact with the first interconnect structure.

7. The solar cell further includes second interconnect structures disposed on the target surface, each of the second interconnect structures electrically connected to at least one of the current collecting electrodes, the size of the second interconnect structures being smaller than the size of the first interconnect structure, and at least a portion of the second interconnect structures being aligned on the same line and being collinear with the connecting line; Among all the current collecting electrodes located on the same target surface, some of the current collecting electrodes contact the first interconnect structure, and the remaining current collecting electrodes contact the second interconnect structure, and the current collecting electrodes in contact with the first interconnect structure are connecting electrodes; 6. The solar cell of claim 5, wherein in the second direction, the distance between two adjacent connection electrodes is D1, at least one of the connection electrodes located in the edge region contacts a plurality of the first interconnect structures, and different first interconnect structures contacting the same connection electrode are distributed spaced apart in the first direction, the distance between the geometric centers of two adjacent first interconnect structures contacting the same connection electrode is D2, D2 corresponding to at least one pair of the first interconnect structures is not equal to D1, and the first interconnect structures of each pair are two adjacent first interconnect structures contacting the same connection electrode.

8. The number of the second interconnect structures intersecting the target line segment or the vector line segment with a tilt angle of 45° is N7; The solar cell according to claim 7 , wherein N7>(1 / 3)N1 and / or N7<N1.

9. The solar cell of claim 7 , wherein a ratio of D1 to D2 corresponding to at least one pair of the first interconnect structures is 6 or more and 12 or less.

10. 2. The solar cell of claim 1, wherein the solar cell further includes bus electrodes provided on the target surface, wherein different bus electrodes located on the same target surface extend in the second direction and are spaced apart in the first direction, each bus electrode is electrically connected to the collecting electrode of the same polarity as itself and is in electrical contact with at least one of the first interconnect structures, and different bus electrodes and different connecting lines correspond one-to-one.

11. the bus electrode is a connection electrode, The distance between two adjacent connection electrodes in the first direction is D1, 11. The solar cell of claim 10, wherein at least one connection electrode contacts a plurality of the first interconnect structures, and different first interconnect structures contacting the same connection electrode are distributed spaced apart in the second direction, the distance between the geometric centers of two adjacent first interconnect structures contacting the same connection electrode is D2, D2 corresponding to at least one pair of the first interconnect structures is not equal to D1, and the first interconnect structures of each pair are two adjacent first interconnect structures contacting the same connection electrode.

12. 12. The solar cell of claim 11, wherein a ratio of D2 to D1 corresponding to at least one pair of the first interconnect structures is 1 to 1.

7.

13. a battery body having a first surface and a second surface facing each other, at least one of the first surface and the second surface being a target surface; current collecting electrodes provided on the target surface, wherein different current collecting electrodes located on the same target surface all extend in a first direction and are spaced apart in a second direction, and the first direction is perpendicular to the second direction; an array of first interconnection structures formed on the target surface, each of the first interconnection structures being electrically connected to at least one of the current collecting electrodes, at least some regions of different first interconnection structures spaced apart in the second direction being located on the same connection line, and the different connection lines being spaced apart in the first direction; A solar cell, wherein the number of connection lines located within the same target surface is N1, the number of first interconnect structures that intersect with target line segments located within the target surface is N2, N1 > N2, and the target line segments are diagonals of the target surface and intersect with any of the connection lines.

14. the solar cell includes at least two divided battery cells spaced apart in the second direction, and a scribe line is formed between two adjacent divided battery cells; The current collecting electrodes of opposite polarities in two adjacent divided battery cells are provided symmetrically with respect to the scribe line, and / or The first interconnection structures of opposite polarities in two adjacent divided battery cells are provided symmetrically with respect to the scribe line; and / or 14. The solar cell according to claim 13, wherein the solar cell further includes bus electrodes provided on the target surface, wherein different bus electrodes located on the same target surface extend in the second direction and are distributed at a distance from each other in the first direction, each bus electrode is electrically connected to the collecting electrode of the same polarity as itself and is in contact with at least one of the first interconnect structures, different bus electrodes and different connecting lines correspond one-to-one, and the bus electrodes of opposite polarities in two adjacent divided battery cells are provided symmetrically with respect to the scribe line.

15. 14. The solar cell of claim 13, wherein the solar cell includes M divided battery cells distributed at a distance from each other in the second direction, where M is a positive integer greater than or equal to 1, and in the same divided battery cell, the geometric centers of two of the first interconnect structures located at edges in the second direction are arranged symmetrically with respect to a center line of the divided battery cell in the second direction.

16. the solar cell further includes bus electrodes provided on the target surface, wherein different bus electrodes located on the same target surface extend in the second direction and are spaced apart in the first direction, each bus electrode is electrically connected to the collecting electrode of the same polarity as itself and contacts at least one of the first interconnect structures, and different bus electrodes correspond to different connecting lines one-to-one; 14. The solar cell of claim 13, wherein the collecting electrodes include first and second collecting electrodes of opposite polarities, the first and second collecting electrodes being alternately spaced apart in the second direction, the bus electrodes include first and second bus electrodes of opposite polarities, the first and second bus electrodes being alternately spaced apart in the first direction, and the bus electrodes and collecting electrodes of opposite polarities being insulated from each other.

17. 17. The solar cell of claim 16, wherein, when the polarities of the two bus electrodes located on the outside in the first direction are opposite, at least two of all the first interconnect structures that intersect with the target line segment are at equal distances from the center line of the target surface in the second direction and have the same polarity.

18. When the solar cell includes two divided battery cells that are spaced apart in the second direction, N2 corresponding to the two divided battery cells is equal, and in the same divided battery cell, the polarities of the two bus electrodes located on the outer side in the first direction are opposite, and the polarities of the two bus electrodes that belong to different divided battery cells and are located on the outer side in the first direction and are provided opposite to each other are opposite, or 17. The solar cell according to claim 16, wherein, when the solar cell includes two divided battery cells spaced apart in the second direction, N2 corresponding to the two divided battery cells is not equal, and in the same divided battery cell, the two bus electrodes located on the outside in the first direction have the same polarity, and the two bus electrodes belonging to different divided battery cells and located on the outside in the first direction and opposite to each other have opposite polarity.

19. The solar cell is a solar cell without a main grid, and the solar cell further includes a second interconnect structure provided on the target surface, each of the second interconnect structures electrically connected to at least one of the current collecting electrodes, the size of the second interconnect structure being smaller than the size of the first interconnect structure, and at least a part of the area of ​​the second interconnect structure being located on the same straight line and being collinear with the connecting line; Among all the current collecting electrodes located on the same target surface, some of the current collecting electrodes contact the first interconnect structure, and the remaining current collecting electrodes contact the second interconnect structure; 14. The solar cell of claim 13, wherein the number of the second interconnect structures crossing the target line segment is N8, where N8>(1 / 2)N1 and / or N8<1.5N1.

20. A solar module comprising the solar cell according to any one of claims 1 to 12 or the solar cell according to any one of claims 13 to 19.

21. A solar module including solar cells and an intra-string interconnection member connecting two adjacent solar cells in series, The solar cell includes a cell body, current collecting electrodes, and first interconnection structures, the cell body having opposing first and second surfaces, at least one of the first and second surfaces being a target surface, the current collecting electrodes being provided on the target surface, different current collecting electrodes located on the same target surface all extending in a first direction and being spaced apart in a second direction, the first direction being perpendicular to the second direction, each of the first interconnection structures being electrically connected to at least one of the current collecting electrodes, each of the intra-string interconnection members being in electrical contact with a corresponding one of the first interconnection structures, and the target surface the number of the first interconnection structures intersecting with the target line segment located within the target surface is N2, and the target line segment is a line segment connecting the midpoint of the longer of two edges extending in the first direction of the target surface and distributed opposite to each other to the apex end point of the shorter of the two edges; the number of the intra-string interconnection members located on the same target surface is N5; the number of the first interconnection structures intersecting with at least one vector line segment with the same 45° inclination angle is N4; and the number of the intra-string interconnection members intersecting with the same 45° inclination vector line segment is N6; A solar module in which N2<(1 / 2)N5 or N6>N4.

22. 22. The solar module of claim 21, wherein N2 corresponding to at least two of the solar cells in the same solar module is equal.

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