photovoltaic modules

Abstract

This disclosure relates to the photovoltaic field and provides a photovoltaic module. The photovoltaic module includes multiple solar cells and a solder strip. Multiple grid lines and solder joints are provided on both the first and second surfaces of the solar cells. The multiple solar cells include first and second solar cells arranged adjacent to each other. The first surface of the first solar cell includes a first edge region and a first middle region, and the second surface of the second solar cell includes a second edge region and a second middle region. The solder strip makes electrical contact with the solder joints on the first surface of the first solar cell and with the solder joints on the second surface of the second solar cell. For the same solder strip, the contact area between at least one solder joint on the first edge region and the solder strip is larger than the contact area between the solder joint on the first middle region and the solder strip, and the contact area between at least one solder joint on the second edge region and the solder strip is larger than the contact area between the solder joint on the second middle region and the solder strip. This disclosure embodiment can at least improve the performance of the photovoltaic module.

Description

Technical Field

[0001] This disclosure relates to the photovoltaic field, and in particular to a photovoltaic module. Background Technology

[0002] With global energy consumption rapidly increasing and traditional fossil fuels becoming increasingly depleted, energy and environmental issues have gradually become two major global concerns. Driven by pressure to address environmental pollution and promote sustainable development, researchers have prioritized the solar photovoltaic industry in the development and utilization of renewable energy.

[0003] Photovoltaic modules are crucial devices for converting solar energy into electrical energy. A photovoltaic module consists of multiple solar cells and solder ribbons. The solar cells have solder joints, and the solder ribbons connect adjacent solar cells. However, currently, there is a risk of incomplete soldering between the solder ribbons and solder joints in some areas of the solar cells, which adversely affects the performance of the photovoltaic module, thus requiring improvement in its performance. Utility Model Content

[0004] This disclosure provides a photovoltaic module that can at least improve the performance of the photovoltaic module.

[0005] According to some embodiments of this disclosure, a photovoltaic module is provided. The photovoltaic module includes: a plurality of solar cells, each solar cell having a first side and a second side facing each other, and each of the first and second sides having a plurality of welding portions along grid lines and electrically in contact with the corresponding grid lines; the plurality of solar cells including first solar cells and second solar cells arranged adjacent to each other, the first side of the first solar cell and the first side of the second solar cell having the same orientation; wherein, the first side of the first solar cell includes a first edge region and a first middle region, the first edge region being adjacent to the second solar cell and located between the first middle region and the second solar cell; the second side of the second solar cell includes a second edge region and a second middle region, the second edge region being adjacent to the first solar cell and located between the second middle region and the first solar cell; a solder ribbon, the solder ribbon being electrically in contact with the welding portions on the first side of the first solar cell and also electrically in contact with the welding portions on the second side of the second solar cell; wherein, for the same solder ribbon, the contact area between at least one welding portion on the first edge region and the solder ribbon is larger than the contact area between the welding portion on the first middle region and the solder ribbon, and the contact area between at least one welding portion on the second edge region and the solder ribbon is larger than the contact area between the welding portion on the second middle region and the solder ribbon.

[0006] In some embodiments, the solder strip includes: a first widening portion electrically connected to at least one solder portion on a first edge region, and / or, the first widening portion electrically contacting at least one of the solder portions on a second edge region; a first extension portion connected to the first widening portion and extending along a first direction; wherein the width of the first widening portion along a second direction is greater than the width of the first extension portion along the second direction.

[0007] In some embodiments, the thickness of the first widened portion is less than the thickness of the first extended portion, and the thickness of the second widened portion is less than the thickness of the second extended portion.

[0008] In some embodiments, the width of the first widened portion along the second direction is 0.4mm to 0.8mm, the width of the first extended portion along the second direction is 0.20mm to 0.28mm, the width of the second widened portion along the second direction is 0.4mm to 0.8mm, and the width of the second extended portion along the second direction is 0.20mm to 0.28mm.

[0009] In some embodiments, the first widened portion is electrically connected to at least one of the welded portions on the first edge region, and the first widened portion is electrically in contact with at least one of the welded portions on the second edge region. The orthographic projection area of ​​the welded portion on the first edge region on the first surface is equal to the orthographic projection area of ​​the welded portion on the first intermediate region on the first surface, and the orthographic projection area of ​​the welded portion on the second edge region on the second surface is equal to the orthographic projection area of ​​the welded portion on the second intermediate region on the second surface.

[0010] In some embodiments, at least one weld portion located on the first edge region is a first weld portion, and a weld portion located on the first intermediate region is a second weld portion, wherein the orthographic projection area of ​​the first weld portion on the first surface is greater than the orthographic projection area of ​​the second weld portion on the first surface; and / or, at least one weld portion located on the second edge region is a third weld portion, and a weld portion located on the second intermediate region is a fourth weld portion, wherein the orthographic projection area of ​​the third weld portion on the second surface is greater than the orthographic projection area of ​​the fourth weld portion on the second surface.

[0011] In some embodiments, the projected area of ​​the first weld portion on the first surface is 0.675 mm². 2 ~1.44mm 2 The projected area of ​​the second welded part on the first surface is 0.18 mm. 2 ~0.6mm 2 The projected area of ​​the third weld on the second surface is 0.675 mm². 2 ~1.44mm 2 The projected area of ​​the fourth weld on the second surface is 0.18 mm. 2 ~0.6mm 2 .

[0012] In some embodiments, the first welding portion includes: a first main body portion and a first gradient portion, the first gradient portion being connected to the first main body portion and located on the side of the first main body portion away from the second battery cell, and the width of the first gradient portion gradually decreasing along a second direction in the direction from the second battery cell to the first battery cell; and / or, the third welding portion includes: a second main body portion and a second gradient portion, the second gradient portion being connected to the second main body portion and located on the side of the second main body portion away from the first battery cell, and the width of the first gradient portion gradually decreasing along a second direction in the direction from the first battery cell to the second battery cell.

[0013] In some embodiments, the first gradient portion includes a first contour line and a second contour line. In the direction from the second battery cell to the first battery cell, the distance between the first contour line and the second contour line along the second direction gradually decreases. The first contour line is an arc, and the second contour line is an arc. In the direction from the second battery cell to the first battery cell, the absolute value of the slope of the first contour line gradually decreases, and the absolute value of the slope of the second contour line gradually decreases. And / or, the second gradient portion includes a third contour line and a fourth contour line. In the direction from the first battery cell to the second battery cell, the distance between the third contour line and the fourth contour line along the second direction gradually decreases. The third contour line is an arc, and the fourth contour line is an arc. In the direction from the first battery cell to the second battery cell, the absolute value of the slope of the third contour line gradually decreases, and the absolute value of the slope of the fourth contour line gradually decreases.

[0014] In some embodiments, the width of the first main body portion along the first direction is 0.6mm to 0.8mm, the length of the first main body portion along the second direction is 1mm to 1.2mm, the width of the first gradient portion along the first direction is 0.3mm to 0.8mm, and the length of the end of the first gradient portion near the first main body portion along the second direction is 1mm to 1.2mm; the width of the second main body portion along the first direction is 0.6mm to 0.8mm, the length of the second main body portion along the second direction is 1mm to 1.2mm, the width of the second gradient portion along the first direction is 0.3mm to 0.8mm, and the length of the end of the second gradient portion near the second main body portion along the second direction is 1mm to 1.2mm.

[0015] In some embodiments, for the same solder strip, the contact area between the solder portion adjacent to the second battery cell on the first edge region and the solder strip is greater than the contact area between the solder portion on the first intermediate region and the solder strip, and the contact area between the solder portion adjacent to the first battery cell on the second edge region and the solder strip is greater than the contact area between the solder portion on the second intermediate region and the solder strip.

[0016] In some embodiments, the battery cell also includes a cut surface and a non-cut surface disposed opposite to each other, wherein the non-cut surface of the first battery cell is disposed opposite to the cut surface of the second battery cell.

[0017] In some embodiments, for the same solder strip, the number of welded portions on the first edge region is less than or equal to 3, and the number of welded portions on the second edge region is less than or equal to 3; and / or, in a first direction, the ratio of the width of the first edge region to the width of the first battery cell is less than or equal to 1 / 4, and the ratio of the width of the second edge region to the width of the second battery cell is less than or equal to 1 / 4.

[0018] In some embodiments, the first side of the first battery cell further includes a third edge region, which is located away from the second battery cell, and a first intermediate region is located between the third edge region and the first edge region; the second side of the second battery cell further includes a fourth edge region, which is located away from the first battery cell, and a second intermediate region is located between the second edge region and the fourth edge region; for the same solder strip, the contact area between at least one welded portion on the third edge region and the solder strip is greater than the contact area between the welded portion on the first intermediate region and the solder strip, and the contact area between at least one welded portion on the fourth edge region and the solder strip is greater than the contact area between the welded portion on the second intermediate region and the solder strip.

[0019] In some embodiments, the solder strip includes: a second widening portion, a third widening portion electrically connected to at least one solder portion on a third edge region, and / or, the second widening portion electrically contacting at least one of the solder portions on a fourth edge region; a first extension portion connected to the second widening portion and extending along a first direction; wherein the width of the second widening portion along a second direction is greater than the width of the first extension portion along the second direction.

[0020] In some embodiments, at least one weld portion located on the third edge region is a fifth weld portion, and a weld portion located on the first intermediate region is a second weld portion, wherein the orthographic projection area of ​​the fifth weld portion on the first surface is greater than the orthographic projection area of ​​the second weld portion on the first surface; and / or, at least one weld portion located on the fourth edge region is a sixth weld portion, and a weld portion located on the second intermediate region is a fourth weld portion, wherein the orthographic projection area of ​​the sixth weld portion on the second surface is greater than the orthographic projection area of ​​the fourth weld portion on the second surface.

[0021] The technical solutions provided in this disclosure have at least the following advantages:

[0022] In the photovoltaic module technical solution provided in this disclosure, for the same solder strip, the contact area between at least one welding part on the first edge region and the solder strip is greater than the contact area between the welding part on the first middle region and the solder strip. That is, the contact area between at least one welding part on the first edge region and the solder strip is larger, which is beneficial to improve the connection strength between at least one welding part on the first edge region and the solder strip, reduce the risk of poor soldering between the welding part on the first edge region and the solder strip, and thus improve the performance of the photovoltaic module.

[0023] Furthermore, for the same solder strip, the contact area between at least one welded part on the second edge region and the solder strip is greater than the contact area between the welded part on the second middle region and the solder strip. That is, the contact area between at least one welded part on the second edge region and the solder strip is larger, which is beneficial to improve the connection strength between at least one welded part on the second edge region and the solder strip, thereby reducing the risk of poor soldering between the welded part and the solder strip on the first edge region, and thus improving the performance of the photovoltaic module. Attached Figure Description

[0024] One or more embodiments are illustrated by way of example with corresponding pictures in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Unless otherwise stated, the pictures in the accompanying drawings do not constitute a limitation on scale. In order to more clearly illustrate the technical solutions in the embodiments of this disclosure or the conventional technology, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of a partial structure of a photovoltaic module in related technologies;

[0026] Figure 2 This is a partial top view of a photovoltaic module in related technologies;

[0027] Figure 3 This is a partial bottom view of a photovoltaic module in related technologies;

[0028] Figure 4 This is a schematic diagram of a first partial structure of a photovoltaic module provided in an embodiment of the present disclosure;

[0029] Figure 5 This is a first partial top view of a photovoltaic module provided in an embodiment of this disclosure;

[0030] Figure 6 This is a first partial bottom view of a photovoltaic module provided in an embodiment of this disclosure;

[0031] Figure 7A schematic diagram of the structure of the first welded part provided in an embodiment of this disclosure;

[0032] Figure 8 A schematic diagram of the structure of the third welding part provided in an embodiment of this disclosure;

[0033] Figure 9 This is another structural schematic diagram of the first welded part provided in an embodiment of the present disclosure;

[0034] Figure 10 This is another structural schematic diagram of the third welded part provided in an embodiment of the present disclosure;

[0035] Figure 11 This is a schematic diagram of a second partial structure of a photovoltaic module provided in an embodiment of this disclosure;

[0036] Figure 12 This is a second partial top view of a photovoltaic module provided in an embodiment of this disclosure;

[0037] Figure 13 This is a second partial bottom view of a photovoltaic module provided in an embodiment of this disclosure;

[0038] Figure 14 This is a schematic diagram of a third partial structure of a photovoltaic module provided in an embodiment of this disclosure;

[0039] Figure 15 This is a third partial top view of a photovoltaic module provided in an embodiment of this disclosure;

[0040] Figure 16 This is a third partial bottom view of a photovoltaic module provided in an embodiment of this disclosure;

[0041] Figure 17 This is a schematic diagram of a fourth partial structure of a photovoltaic module provided in an embodiment of this disclosure;

[0042] Figure 18 This is a fourth partial top view of a photovoltaic module provided in an embodiment of this disclosure;

[0043] Figure 19 This is a fourth partial bottom view of a photovoltaic module provided in an embodiment of this disclosure;

[0044] Figure 20 A schematic diagram of a fifth partial structure of a photovoltaic module provided in an embodiment of this disclosure;

[0045] Figure 21 A fifth partial top view of a photovoltaic module provided in an embodiment of this disclosure;

[0046] Figure 22 This is a fifth partial bottom view of a photovoltaic module provided in an embodiment of the present disclosure;

[0047] Figure 23 A schematic diagram of the structure of the fifth welding part provided in an embodiment of this disclosure;

[0048] Figure 24 This is a schematic diagram of a sixth welding part provided in an embodiment of the present disclosure. Detailed Implementation

[0049] Figure 1 This is a schematic diagram of a partial structure of a photovoltaic module in related technologies. Figure 2 This is a partial top view of a photovoltaic module in related technologies. Figure 3 This is a partial bottom view of a photovoltaic module in related technologies.

[0050] refer to Figures 1 to 3 The photovoltaic module includes multiple solar cells 10 and solder ribbons 14. Each solar cell 10 includes a first surface 11 and a second surface 12 facing each other. Both the first surface 11 and the second surface 12 are provided with multiple grid lines (not shown) and solder portions 13 that are electrically in contact with the corresponding grid lines. The multiple solar cells 10 include first solar cells 10a and second solar cells 10b arranged adjacent to each other. The first surface 11 of the first solar cell 10a and the first surface 11 of the second solar cell 10b face the same direction. The first surface 11 of the first solar cell 10a includes a first edge region 111 and a first middle region 112. The first edge region 111 is adjacent to the second solar cell 10b and is located between the first middle region 112 and the second solar cell 10b. The second surface 12 of the second solar cell 10b includes a second edge region 121 and a second middle region 122. The second edge region 121 is adjacent to the first solar cell 10a and is located between the second middle region 122 and the first solar cell 10a. The solder strip 14 makes electrical contact with the solder portion 13 on the first side 11 of the first battery cell 10a, and also makes electrical contact with the solder portion 13 on the second side 12 of the second battery cell 10b.

[0051] Among them, the welding parts 13 on the first edge region 111 and the second edge region 121 are prone to poor welding with the welding strip 14 due to stress concentration, which reduces the performance of the photovoltaic module.

[0052] Therefore, the performance of photovoltaic modules in related technologies needs to be improved.

[0053] This disclosure provides a photovoltaic module in which at least one welded part on the first edge region has a large contact area with the solder strip, which is beneficial to improve the connection strength between at least one welded part on the first edge region and the solder strip, reduce the risk of poor soldering between the welded part on the first edge region and the solder strip, thereby improving the performance of the photovoltaic module.

[0054] Furthermore, for the same solder strip, the contact area between at least one welded part on the second edge region and the solder strip is larger, which is beneficial to improve the connection strength between at least one welded part on the second edge region and the solder strip, thereby reducing the risk of poor soldering between the welded part on the first edge region and the solder strip, and thus improving the performance of the photovoltaic module.

[0055] Understandably, for the same solder strip, when the first edge region has multiple solder joints, and only one solder joint in the first edge region has a larger contact area with the solder strip than the solder joint in the first middle region, the larger contact area between this single solder joint and the solder strip results in a stronger connection. This stronger connection allows the solder joint to withstand greater stress, dispersing the stress from other solder joints in the first edge region. This reduces the risk of poor soldering in the entire first edge region and improves the performance of the photovoltaic module. In other words, even if only one solder joint in the first edge region has a larger contact area with the solder strip than the solder joint in the first middle region, the performance of the photovoltaic module can still be improved.

[0056] Similarly, for the same solder strip, when the second edge region has multiple solder joints, if only one solder joint in the second edge region has a larger contact area with the solder strip than the solder joint in the second middle region, the larger contact area between this single solder joint and the solder strip results in a stronger connection. This stronger connection allows the solder joint to withstand greater stress, dispersing the stress from other solder joints in the second edge region. This reduces the risk of poor soldering in the entire second edge region and improves the performance of the photovoltaic module. In other words, even if only one solder joint in the second edge region has a larger contact area with the solder strip than the solder joint in the second middle region, the performance of the photovoltaic module can still be improved.

[0057] In the description of the embodiments of this disclosure, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary or secondary relationship of the indicated technical features. In the description of the embodiments of this disclosure, "a plurality of" means two or more, unless otherwise explicitly defined.

[0058] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this disclosure. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0059] In the description of the embodiments of this disclosure, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent three cases: A exists, A and B exist simultaneously, and B exists. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0060] In the description of the embodiments of this disclosure, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this disclosure and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this disclosure.

[0061] In the accompanying drawings corresponding to the embodiments of this disclosure, the thickness and area of ​​the layers are enlarged for better understanding and ease of description. When describing a component (such as a layer, film, region, or substrate) on or on the surface of another component, the component may be "directly" located on the surface of the other component, or there may be a third component between the two components. Conversely, when describing a component on the surface of another component, or when another component is formed or disposed on the surface of a component, it indicates that there is no third component between the two components. Furthermore, when describing a component as being "generally" formed on another component, it means that the component is not formed on the entire surface (or front surface) of the other component, nor is it formed on a portion of the edge of the entire surface.

[0062] In the description of embodiments of this disclosure, when a component "includes" another component, other components are not excluded unless otherwise stated, and may be further included. Furthermore, when a component such as a layer, film, region, or plate is referred to as being "on / located" on another component, it can be "directly on" the other component (i.e., located on the surface of the other component with no other components between them), or another component may be present therein. Additionally, when a component such as a layer, film, region, or plate is "directly located" on another component, or when a component such as a layer, film, region, or plate is located on the surface of another component, it indicates that no other components are located therein.

[0063] The embodiments of this disclosure will now be described in detail with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details have been provided in the embodiments of this disclosure to facilitate a better understanding of the disclosure. However, the technical solutions claimed in this disclosure can be implemented even without these technical details and various variations and modifications based on the following embodiments.

[0064] Figure 4 This is a schematic diagram of a first partial structure of a photovoltaic module provided in an embodiment of this disclosure. Figure 5 This is a first partial top view of a photovoltaic module provided in an embodiment of this disclosure. Figure 6 This is a first partial bottom view of a photovoltaic module provided in an embodiment of this disclosure.

[0065] refer to Figures 4 to 6 The photovoltaic module includes: a plurality of solar cells 20, each solar cell 20 having a first surface 21 and a second surface 22 facing each other, each of the first surface 21 and the second surface 22 having a plurality of grid lines (not shown) and a welding portion 23 electrically contacting the corresponding grid lines; the plurality of solar cells 20 includes a first solar cell 20a and a second solar cell 20b arranged adjacent to each other, the first surface 21 of the first solar cell 20a and the first surface 21 of the second solar cell 20b having the same orientation; wherein, the first surface 21 of the first solar cell 20a includes a first edge region 211 and a first middle region 212, the first edge region 211 being adjacent to the second solar cell 20b and located between the first middle region 212 and the second solar cell 20b; the second surface 22 of the second solar cell 20b includes a second edge region 221 and a second middle region 222, the second edge region 221 being adjacent to the first solar cell 20a and located between the second middle region 222 and the first solar cell 20a. The photovoltaic module also includes a solder ribbon 24, which makes electrical contact with a welding portion 23 on the first surface 21 of the first cell 20a and also makes electrical contact with a welding portion 23 on the second surface 22 of the second cell 20b. Specifically, for the same solder ribbon 24, the contact area between at least one welding portion 23 on the first edge region 211 and the solder ribbon 24 is greater than the contact area between the welding portion 23 on the first intermediate region 212 and the solder ribbon 24, and the contact area between at least one welding portion 23 on the second edge region 221 and the solder ribbon 24 is greater than the contact area between the welding portion 23 on the second intermediate region 222 and the solder ribbon 24.

[0066] Photovoltaic modules are used to convert solar energy into electrical energy.

[0067] The solar cell 20 can be one or any combination of TOPCon (Tunnel Oxide Passivated Contact), HIT / HJT (Heterojunction Technology), PERC (Passivated Emitter Rear Cell), thin-film solar cells, and tandem solar cells. Thin-film solar cells include, but are not limited to, perovskite thin-film solar cells, copper indium selenide (CIGS) thin-film solar cells, gallium arsenide (GaAs) thin-film solar cells, and cadmium sulfide (CdS) thin-film solar cells. Tandem solar cells include, but are not limited to, perovskite cells stacked with crystalline silicon cells, perovskite cells stacked with perovskite cells, and perovskite cells stacked with thin-film cells.

[0068] The solar cell 20 can be a cell with a main grid, which can shorten the current conduction path and reduce internal losses, thereby increasing the power of the photovoltaic module. The solar cell 20 can also be a cell without a main grid, in which case the solder ribbon 24 is used to replace the original main grid and is directly connected to the fine grid, which can significantly reduce the consumption of silver paste, thereby reducing the cost of the photovoltaic module.

[0069] The battery cell 20 has a first surface 21 and a second surface 22 facing each other. In some embodiments, the battery cell 20 is a single-sided battery, in which case the first surface 21 can serve as a light-receiving surface to receive incident light, and the second surface 22 serves as a backlight surface. In some embodiments, the battery cell 20 is a double-sided battery, in which case both the first surface 21 and the second surface 22 of the substrate can serve as light-receiving surfaces and can both be used to receive incident light.

[0070] Multiple solar cells 20 include first solar cells 20a and second solar cells 20b arranged adjacent to each other. It is understood that the terms first solar cell 20a and second solar cell 20b are merely used to illustrate the positional relationship between adjacent solar cells 20 and the solder ribbon 24; in reality, there is no substantial difference between first solar cell 20a and second solar cell 20b. A solar cell 20 can be either first solar cell 20a or second solar cell 20b. This is because the first surface 21 of a solar cell 20 is connected to a solder ribbon 24, and the second surface 22 of the same solar cell 20 is also connected to a solder ribbon 24. Specifically, when the first surface 21 of a solar cell 20 is connected to a solder ribbon 24, this solar cell 20 is designated as first solar cell 20a. A solar cell 20 connected to the same solder ribbon 24 and with the same solder ribbon 24 connected to the second surface 22 can be designated as second solar cell 20b. When the second side 22 of a cell 20 is connected to another solder strip 24, the cell 20 can be referred to as the second cell 20b. The cell 20 connected to the same solder strip 24 and the same solder strip 24 connected to the first side 21 of the cell 20 is referred to as the first cell 20a.

[0071] The first surface 21 includes a first edge region 211 and a first intermediate region 212, with at least one welded portion 23 provided on the first edge region 211. The second surface 22 includes a second edge and a second intermediate region 222, with at least one welded portion 23 provided on the second edge region 221. It is understood that the first edge region 211 and the first intermediate region 212, as well as the second edge region 221 and the second intermediate region 222, are artificially defined.

[0072] In some embodiments, for the same solder strip 24, the number of solder portions 23 on the first edge region 211 is less than or equal to 3, and the number of solder portions 23 on the second edge region 221 is less than or equal to 3; and / or, in the first direction X, the ratio of the width of the first edge region 211 to the width of the first battery cell 20a is less than or equal to 1 / 4, and the ratio of the width of the second edge region 221 to the width of the second battery cell 20b is less than or equal to 1 / 4.

[0073] The grid lines are used to collect and transmit the current generated by the solar cell 20.

[0074] The grid line material can be one or more of aluminum, silver, gold, nickel, molybdenum, or copper.

[0075] Welding section 23 is used for welding grid lines and welding strips 24.

[0076] The material of the welded part 23 can be one or more of aluminum, silver, gold, nickel, molybdenum or copper.

[0077] The solder strip 24 connects adjacent battery cells 20 by means of the solder portion 23 connecting the first side 21 of the first battery cell 20a and the second side 22 of the second battery cell 20b, thereby forming a battery string.

[0078] In some embodiments, the solder strip 24 includes a first widening portion 241 and a first extension portion 242. The first widening portion 241 is electrically connected to at least one welding portion 23 on the first edge region 211 and is in electrical contact with at least one welding portion 23 on the second edge region 221. The first extension portion 242 is connected to the first widening portion 241 and extends along a first direction. The width of the first widening portion 241 along the second direction Y is greater than the width of the first extension portion 242 along the second direction Y.

[0079] The first extension 242 is connected to the first widening portion 241 and extends along the first direction X, making electrical contact with the welding portions 23 on the first intermediate region 212 and the second intermediate region 222. The width of the first widening portion 241 along the second direction Y is greater than the width of the first extension 242 along the second direction Y, i.e., the width of the first widening portion 241 is larger. This larger width of the first widening portion 241 can increase the contact area between the welding portions 23 and the solder strips 24 on the first edge region 211 and the second edge region 222, reducing the risk of poor soldering between the welding portions 23 and the solder strips 24 on the first edge region 211 and the second edge region 222, thereby improving the performance of the photovoltaic module. Furthermore, the smaller width of the first extension 242 can reduce the shading area of ​​the first extension 242 on the solar cell 20, which is also beneficial to improving the performance of the photovoltaic module.

[0080] In some embodiments, the thickness of the first widened portion 241 is less than the thickness of the first extended portion 242. The larger width of the first widened portion 241 can be achieved by reducing the thickness of the first widened portion 241, thus providing an initial solder strip with the same thickness in all parts. Then, the corresponding area of ​​the first widened portion 241 is flattened to reduce the thickness of the first widened portion 241, thereby increasing the thickness of the first widened portion 241 along the second direction Y. This simplifies the fabrication process of the solder strip 24 and is beneficial for improving the efficiency of the photovoltaic module.

[0081] In some embodiments, the thickness of the first widened portion 241 is 0.06 mm to 0.13 mm, for example 0.06 mm, 0.08 mm, 0.1 mm, 0.12 mm or 0.13 mm, and the thickness of the first extended portion 242 is 0.2 mm to 0.28 mm, for example 0.2 mm, 0.22 mm, 0.24 mm, 0.26 mm or 0.28 mm.

[0082] In some embodiments, the width of the first widened portion 241 along the second direction Y is 0.4mm to 0.8mm, for example, 0.4mm, 0.5mm, 0.6mm, 0.7mm, or 0.8mm. The width of the first widened portion 241 along the second direction Y is within the above range, providing sufficient connection strength with the welded portion 23 to reduce the risk of incomplete soldering between the welded portion 23 and the solder strip 24 on the first edge region 211. It also avoids the first widened portion 241 being too wide, which could affect the absorption of sunlight by the solar cell 20.

[0083] The width of the first extension 242 along the second direction Y is 0.2mm to 0.28mm, for example, 0.2mm, 0.22mm, 0.24mm, 0.26mm, or 0.28mm. Since the width of the first extension 242 along the second direction Y is within the above range, a smaller width of the first extension 242 can reduce the shading area of ​​the first extension 242 on the solar cell 20, thereby improving the performance of the photovoltaic module.

[0084] In some embodiments, at least one welding portion 23 located on the first edge region 311 is a first welding portion 231, and the welding portion 23 located on the first intermediate region 212 is a second welding portion 232. The projected area of ​​the first welding portion 231 on the first surface 21 is larger than the projected area of ​​the second welding portion 232 on the first surface 21. The larger projected area of ​​the first welding portion 231 on the first surface 21 increases the contact area between the first welding portion 231 and the solder strip 24, improving the connection strength between the first welding portion 231 and the solder strip 24. This helps reduce the risk of poor soldering between the welding portion 23 and the solder strip 24 in the first edge region 311, thereby improving the performance of the photovoltaic module. Furthermore, the smaller projected area of ​​the second welding portion 232 on the first surface 21 helps reduce the shading area of ​​the second welding portion 232 on the first surface 21, thus further improving the performance of the photovoltaic module.

[0085] At least one welding portion 23 located on the second edge region 221 is a third welding portion 233, and the welding portion 23 located on the second intermediate region 222 is a fourth welding portion 234. The projected area of ​​the third welding portion 233 on the second surface 22 is larger than that of the fourth welding portion 234 on the second surface 22. The larger projected area of ​​the third welding portion 233 on the second surface 22 increases the contact area between the third welding portion 233 and the solder strip 34, improving the connection strength between the third welding portion 233 and the solder strip 24. This helps reduce the risk of poor soldering between the welding portion 23 and the solder strip 24 in the second edge region 221, thereby improving the performance of the photovoltaic module. Furthermore, the smaller projected area of ​​the fourth welding portion 234 on the second surface 22 helps reduce the shading area of ​​the fourth welding portion 234 on the second surface 22, thus further improving the performance of the photovoltaic module.

[0086] In some embodiments, the projected area of ​​the first welded portion 231 on the first surface 21 is 0.675 mm. 2 ~1.44mm 2 For example, 0.675mm 2 0.7mm 2 0.9mm 2 1.1mm 2 1.3mm 2 Or 1.44mm 2 The projected area of ​​the first welding part 231 on the first surface 21 is within the above-mentioned range. The larger projected area of ​​the first welding part 231 on the first surface 21 can increase the contact area between the first welding part 231 and the welding strip 24, improve the connection strength between the first welding part 231 and the welding strip 24, and help reduce the risk of poor welding between the welding part 23 and the welding strip 24 in the first edge area 311, thereby improving the performance of the photovoltaic module.

[0087] The projected area of ​​the second welded part 232 on the first surface 21 is 0.18 mm. 2 ~0.6mm 2 For example, 0.18mm 2 0.2mm 2 0.3mm 2 0.4mm 2 0.5mm 2 or 0.6mm 2 The projected area of ​​the second welding part 232 on the first surface 21 is within the above-mentioned range. The smaller projected area of ​​the second welding part 232 on the first surface 21 is beneficial to reducing the shading area of ​​the second welding part 232 on the first surface 21, thereby improving the performance of the photovoltaic module.

[0088] The projected area of ​​the third welded part 233 on the second surface 22 is 0.675 mm². 2 ~1.44mm 2 For example, 0.675mm 2 0.7mm 2 0.9mm 2 1.1mm 2 1.3mm 2 Or 1.44mm 2 The projected area of ​​the third weld portion 233 on the second surface 22 is within the aforementioned range. The larger projected area of ​​the third weld portion 233 on the second surface 22 can increase the contact area between the third weld portion 233 and the solder strip 24, improve the connection strength between the third weld portion 233 and the solder strip 24, and help reduce the risk of poor soldering between the weld portion 23 and the solder strip 24 in the third edge area, thereby improving the performance of the photovoltaic module.

[0089] The projected area of ​​the fourth welded part 234 on the second surface 22 is 0.18 mm². 2 ~0.6mm 2 For example, 0.18mm 2 0.2mm 2 0.3mm 2 0.4mm 2 0.5mm 2 or 0.6mm 2 The projected area of ​​the fourth welding part 234 on the second surface 22 is within the above-mentioned range. The smaller projected area of ​​the fourth welding part 234 on the second surface 22 is beneficial to reducing the light-shielding area of ​​the fourth welding part 234 on the second surface 22, thereby improving the performance of the photovoltaic module.

[0090] Figure 7 This is a schematic diagram of a first welded part provided in an embodiment of the present disclosure.

[0091] refer to Figure 5 and Figure 7 In some embodiments, the first welding portion 231 includes a first main body portion 2311 and a first gradient portion 2312. The first gradient portion 2312 is connected to the first main body portion 2311 and is located on the side of the first main body portion 2311 opposite to the second solar cell 20b. In the direction from the second solar cell 20b to the first solar cell 20a, the width of the first gradient portion 2312 gradually decreases along the second direction Y. Compared to using a first gradient portion 2312 with a constant width (i.e., the width of the first gradient portion is the same everywhere along the second direction), the gradual decrease in the width of the first gradient portion 2312 along the second direction Y can reduce the light-shielding area of ​​the first gradient portion 2312 on the solar cell 20, thereby improving the performance of the photovoltaic module.

[0092] Figure 8 This is a schematic diagram of a third welding part provided in an embodiment of the present disclosure.

[0093] refer to Figure 6 and Figure 8 The third welding portion 233 includes a second main body portion 2331 and a second gradient portion 2332. The second gradient portion 2332 is connected to the second main body portion 2331 and is located on the side of the second main body portion 2331 opposite to the first solar cell 20a. In the direction from the first solar cell 20a to the second solar cell 20b, the width of the first gradient portion 2332 gradually decreases along the second direction Y. Compared to using a second gradient portion 2332 with a constant width (i.e., the width of the second gradient portion 2332 is the same everywhere along the second direction Y), the gradually decreasing width of the second gradient portion 2332 along the second direction Y can reduce the light-shielding area of ​​the second gradient portion 2332 on the solar cell 20, thereby improving the performance of the photovoltaic module.

[0094] Figure 9 This is another structural schematic diagram of the first welded part provided in an embodiment of this disclosure.

[0095] refer to Figure 5 and Figure 9In some embodiments, the first gradient portion 2312 includes a first contour line and a second contour line. In the direction from the second battery cell 20b to the first battery cell 20a, the distance between the first and second contour lines along the second direction Y gradually decreases. Both the first and second contour lines are arcs. In the direction from the second battery cell 20b to the first battery cell 20a, the absolute value of the slope of both the first and second contour lines gradually decreases. The distance between the first and second contour lines along the second direction Y is the width of the first gradient portion 2312 along the second direction Y. Compared to a scheme where the first and second contour lines are straight lines, the gradual decrease in the absolute value of the slope of both the first and second contour lines ensures sufficient contact area between the solder ribbon 24 and the first gradient portion 2312 while saving material in the first gradient portion 2312.

[0096] Figure 10 This is another structural schematic diagram of the third welded part provided in an embodiment of this disclosure.

[0097] refer to Figure 6 and Figure 10 The second gradient section 2332 includes a third contour line and a fourth contour line. In the direction from the first battery cell 20a to the second battery cell 20b, the distance between the third and fourth contour lines along the second direction Y gradually decreases. Both the third and fourth contour lines are arcs. In the direction from the first battery cell 20a to the second battery cell 20b, the absolute value of the slope of both the third and fourth contour lines gradually decreases. The distance between the third and fourth contour lines along the second direction Y is the width of the second gradient section 2332 along the second direction Y. Compared to a scheme where the third and fourth contour lines are straight lines, the gradual decrease in the absolute value of the slope of both contour lines ensures sufficient contact area between the solder strip 24 and the second gradient section 2332 while saving material in the second gradient section 2332.

[0098] Figures 5 to 10 In the example, the first main body 2311 is shown to have a rectangular orthographic projection shape on the first surface 21, and the second main body 3331 is shown to have a rectangular orthographic projection shape on the second surface 3232. In reality, the orthographic projection shape of the first main body on the first surface can also be a circle, trapezoid, polygon, etc., and the orthographic projection shape of the second main body on the second surface can also be a circle, trapezoid, polygon, etc.

[0099] Continue to refer to Figure 5 and Figure 6In some embodiments, the width of the first main body portion 2311 along the first direction X is 0.6mm to 0.8mm, for example, 0.6mm, 0.7mm, or 0.8mm, and the length of the first main body portion 2311 along the second direction Y is 1mm to 1.2mm, for example, 1mm, 1.1mm, or 1.2mm. The width and length of the first main body portion 2311 being within the above ranges provides a larger contact area for the first welding portion 331 to contact the welding strip 24, which is beneficial for improving the connection strength between the first welding portion 331 and the welding strip 34.

[0100] The width of the first gradient portion 2312 along the first direction X is 0.3mm to 0.8mm, for example, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm or 0.8mm. The length of the end of the first gradient portion 2312 near the first main body portion 2311 along the second direction Y is 1mm to 1.2mm, for example, 1mm, 1.1mm or 1.2mm.

[0101] The width of the second main body portion 2331 along the first direction X is 0.6mm to 0.8mm, for example, 0.6mm, 0.7mm, or 0.8mm, and the length of the second main body portion 2331 along the second direction Y is 1mm to 1.2mm, for example, 1mm, 1.1mm, or 1.2mm. The width and length of the second main body portion 2331 are within the above ranges. A larger width and length of the second main body portion 2331 can provide a larger contact area for the third welding portion 333 to contact the welding strip 34, which is beneficial for improving the connection strength between the third welding portion 333 and the welding strip 34.

[0102] The width of the second gradient portion 2332 along the first direction X is 0.3mm to 0.8mm, for example, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm or 0.8mm. The length of the end of the second gradient portion 2332 near the second main body portion 2331 along the second direction Y is 1mm to 1.2mm, for example, 1mm, 1.1mm or 1.2mm.

[0103] In other embodiments, the projected area of ​​the weld portion on the first edge region on the first surface can be equal to the projected area of ​​the weld portion on the first middle region on the first surface, and the projected area of ​​the weld portion on the second edge region on the second surface can be equal to the projected area of ​​the weld portion on the second middle region on the second surface. That is, the contact area between at least one weld portion on the first edge region and the solder strip can be increased simply by setting a larger width for the first widening portion, without increasing the projected area of ​​the weld portion on the first edge region on the first surface. This avoids the negative impact on sunlight absorption by the photovoltaic module caused by increasing the projected area of ​​the weld portion on the first edge region on the first surface, thereby improving the performance of the photovoltaic module.

[0104] In some embodiments, for the same solder strip 24, the contact area between the solder portion 23 adjacent to the second cell 20b on the first edge region 211 and the solder strip 24 is larger than the contact area between the solder portion 23 and the solder strip 24 on the first intermediate region 212, and the contact area between the solder portion 23 adjacent to the first cell 20a on the second edge region 221 is larger than the contact area between the solder portion 23 and the solder strip 24 on the second intermediate region 222. The solder portion 23 adjacent to the second cell 20b on the first edge region 211, i.e., the solder portion 23 closest to the second cell 20b, and the solder strip 24 have the greatest risk of poor soldering. Therefore, setting a larger contact area for the solder portion 23 adjacent to the second cell 20b on the first edge region 211 can effectively reduce the risk of poor soldering between the solder portion 23 and the solder strip 24 on the first edge region 211, thereby improving the performance of the photovoltaic module. The weld portion 23 and the solder strip 24 closest to the first cell 20a on the second edge region 221 have the greatest risk of poor soldering. Therefore, by setting the contact area of ​​the weld portion 23 adjacent to the first cell 20a on the second edge region 221 to be larger, the risk of poor soldering between the weld portion 23 and the solder strip 24 on the second edge region 221 can be effectively reduced, thereby improving the performance of the photovoltaic module.

[0105] Continue to refer to Figures 4 to 6 In some embodiments, the solar cell 20 further includes a cut surface 25 and a non-cut surface 26 disposed opposite to each other, with the non-cut surface 26 of the first solar cell 20a facing the cut surface 25 of the second solar cell 20b. This positions the solder ribbon 24 above the non-cut surface 26 of the first solar cell 20a, preventing the solder ribbon 24 from being positioned above the cut surface 25 with some cutting damage when the cut surface 25 of the first solar cell 20a and the non-cut surface 26 of the second solar cell 20b are facing each other. This avoids the risk of the solar cell 20 cracking due to stress from the solder ribbon 24 on the cut surface 25 with cutting damage during the lamination process of the photovoltaic module.

[0106] The solar cell 20 can be a sliced ​​cell. A sliced ​​cell refers to a cell formed by cutting a complete cell into slices.

[0107] The solar cell 20 may include chamfers (not shown) located on opposite sides of the non-cut surface 26. Chamfers can effectively reduce stress concentration at the edges of the solar cell 20, thereby reducing the risk of the solar cell 20 breaking due to impact or mechanical stress during production, transportation, and use.

[0108] In some embodiments, the photovoltaic module further includes an encapsulating film and a cover plate. The encapsulating film covers the surface of the cell string; the cover plate covers the surface of the encapsulating film opposite to the cell string.

[0109] In some embodiments, the encapsulating film includes a first encapsulating layer and a second encapsulating layer. The first encapsulating layer covers one of the first surface 21 and the second surface 22 of the battery cell 20, and the second encapsulating layer covers the other of the first surface 21 and the second surface 22 of the battery cell 20. Specifically, at least one of the first encapsulating layer or the second encapsulating layer can be an organic encapsulating film such as polyvinyl butyral (PVB) film, ethylene-vinyl acetate copolymer (EVA) film, polyvinyl octene coelastomer (POE) film, or polyethylene terephthalate (PET) film.

[0110] In some embodiments, the cover plate can be a glass cover plate, a plastic cover plate, or other cover plate with light-transmitting function. Specifically, the surface of the cover plate facing the encapsulating film can be an uneven surface or a textured surface containing multiple raised structures, thereby increasing the utilization rate of incident light. The cover plate includes a first cover plate and a second cover plate, the first cover plate being opposite to the first encapsulation layer, and the second cover plate being opposite to the second encapsulation layer.

[0111] In this embodiment of the present disclosure, by setting the width of the first widened portion 241 on the first edge region 211 and the second edge region 221 to be larger, and by increasing the orthogonal projection area of ​​the first welding portion 231 on the first surface 21 and the orthogonal projection area of ​​the third welding portion 233 on the second edge region 221 on the second surface 22, the contact area between at least one welding portion 23 on the first edge region 211 and the welding strip 24 and the welding strip 24 on the second edge region 221 can be increased. This can effectively improve the connection strength between the welding portion 23 on the first edge region 211 and the welding strip 24 on the second edge region 221 and enhance the performance of the photovoltaic module.

[0112] The tensile strength of the welded portion and the weld strip in Example 1 and Comparative Example 1 was tested using a tensile testing machine. In Comparative Example 1, the welded portion on the first and second edge regions was rectangular, with a width of 1.2 mm along the first direction and a length of 0.8 mm along the second direction. The weld strip in contact with this welded portion had a width of 0.2 mm along the second direction. In Example 1, the welded portion on the first and second edge regions included a main body (see reference...). Figure 8 and Figure 9 The first or second main body (in the text) and the transition section (see reference) Figure 8 and Figure 9The first or second gradient portion (in the example) has a main body portion with a width of 1.2 mm along the first direction and a length of 0.8 mm along the second direction. The gradient portion has a width of 0.8 mm along the first direction and a length of 1.2 mm at the end of the gradient portion near the main body portion. The weld strip in contact with the weld portion has a width of 0.4 mm along the second direction. Test results show that the tensile force between the weld strip and the weld portion in Comparative Example 1 is 2.4 N / mm, and the tensile force between the weld strip and the weld portion in Example 1 is 3.5 N / mm. The test results show that this embodiment of the present disclosure, by increasing the orthographic projection area of ​​the weld portion and widening the width of the weld strip connected to the corresponding weld portion, can effectively improve the tensile force between the weld strip and the weld portion, thereby improving the connection strength between the weld strip and the weld portion.

[0113] In addition, the photovoltaic modules of Example 1 and Comparative Example 1 were subjected to TC400 thermal cycling aging tests. The cells were subjected to 400 thermal cycles, with each cycle involving a temperature increase from -40°C to 85°C, holding at that temperature for 6 hours, followed by a decrease to -40°C and holding for another 6 hours. The temperature change rate was 20°C / h. The test results showed that the power degradation of the photovoltaic module in Comparative Example 1 was -3.5%, and the power degradation of the photovoltaic module in Example 1 was -2.7%. The test results demonstrate that this embodiment of the invention, by increasing the projected area of ​​the welded portion and widening the width of the weld strip connecting the corresponding welded portion, can reduce the power degradation of the photovoltaic module and improve its performance.

[0114] Figure 11 This is a schematic diagram of a second partial structure of a photovoltaic module provided in an embodiment of this disclosure. Figure 12 This is a second partial top view of a photovoltaic module provided in an embodiment of this disclosure. Figure 13 This is a second partial bottom view of a photovoltaic module provided in an embodiment of this disclosure.

[0115] refer to Figures 11 to 13The photovoltaic module includes: a plurality of solar cells 30, each solar cell 30 having a first surface 31 and a second surface 32 facing each other, each of the first surface 31 and the second surface 32 having a plurality of grid lines (not shown) and a welding portion 33 electrically contacting the corresponding grid lines; the plurality of solar cells 30 includes a first solar cell 30a and a second solar cell 30b arranged adjacent to each other, the first surface 31 of the first solar cell 30a and the first surface 31 of the second solar cell 30b having the same orientation; wherein, the first surface 31 of the first solar cell 30a includes a first edge region 311 and a first middle region 312, the first edge region 311 being adjacent to the second solar cell 30b and located between the first middle region 312 and the second solar cell 30b; the second surface 32 of the second solar cell 30b includes a second edge region 321 and a second middle region 322, the second edge region 321 being adjacent to the first solar cell 30a and located between the second middle region 322 and the first solar cell 30a. The photovoltaic module also includes a solder ribbon 34, which makes electrical contact with a solder portion 33 on the first surface 31 of the first solar cell 30a and also with a solder portion 33 on the second surface 32 of the second solar cell 30b. Specifically, for the same solder ribbon 34, the contact area between at least one solder portion 33 on the first edge region 311 and the solder ribbon 34 is larger than the contact area between the solder portion 33 on the first intermediate region 312 and the solder ribbon 34, and the contact area between at least one solder portion 33 on the second edge region 321 and the solder ribbon 34 is larger than the contact area between the solder portion 33 on the second intermediate region 322 and the solder ribbon 34.

[0116] In some embodiments, the solder strip 34 includes a first widening portion 341 and a first extension portion 342. The first widening portion 341 is electrically connected to at least one solder portion 33 on the first edge region 311. The first extension portion 342 is connected to the first widening portion 341 and extends along a first direction. The width of the first widening portion 341 along the second direction Y is greater than the width of the first extension portion 342 along the second direction Y.

[0117] The first extension 342 makes electrical contact with the welding portion 33 on the first intermediate region 312.

[0118] In some embodiments, the projected area of ​​the weld portion 33 on the first edge region 311 on the first surface 31 is equal to the projected area of ​​the weld portion 33 on the first intermediate region 312 on the first surface 31. That is, the contact area between at least one weld portion 33 on the first edge region 311 and the solder strip 34 can be increased simply by setting the width of the first widening portion 341 on the first edge region 311 to be larger.

[0119] In some embodiments, at least one weld portion 33 located on the second edge region 321 is a third weld portion 333, and the weld portion 33 located on the second middle region 322 is a fourth weld portion 334. The orthogonal projection area of ​​the third weld portion 333 on the second surface 32 is greater than the orthogonal projection area of ​​the fourth weld portion 334 on the second surface 32.

[0120] In some embodiments, the width of the solder strip 34 on the second edge region 321 along the second direction Y is equal to the width of the solder strip 34 on the second middle region 322 along the second direction Y. That is, the contact area between the third solder portion 333 on the second edge region 321 and the solder strip 34 can be increased simply by increasing the projected area of ​​the third solder portion 333 on the second surface 32, without increasing the width of a portion of the solder strip 34 on the second edge region 321. This avoids the negative impact on sunlight absorption by the photovoltaic module caused by increasing the width of a portion of the solder strip 34 on the second edge region 321, thereby improving the performance of the photovoltaic module.

[0121] It should be noted that the relevant parameters of the first widened portion 341, the first extended portion 342, the third welded portion 333, and the fourth welded portion 344 in the embodiments of this disclosure can be referred to the relevant parameters of the first widened portion 241, the first extended portion 242, the third welded portion 233, and the fourth welded portion 244 in the foregoing embodiments, and will not be repeated here.

[0122] Figure 14 This is a schematic diagram of a third partial structure of a photovoltaic module provided in an embodiment of this disclosure. Figure 15 This is a third partial top view of a photovoltaic module provided in an embodiment of this disclosure. Figure 16 This is a third partial bottom view of a photovoltaic module provided in an embodiment of this disclosure.

[0123] refer to Figures 14 to 16The photovoltaic module includes: a plurality of solar cells 40, each solar cell 40 having a first surface 41 and a second surface 42 facing each other, each of the first surface 41 and the second surface 42 having a plurality of grid lines (not shown) and a welding portion 43 electrically contacting the corresponding grid lines; the plurality of solar cells 40 includes a first solar cell 40a and a second solar cell 40b arranged adjacent to each other, the first surface 41 of the first solar cell 40a and the first surface 41 of the second solar cell 40b having the same orientation; wherein, the first surface 41 of the first solar cell 40a includes a first edge region 411 and a first middle region 412, the first edge region 411 being adjacent to the second solar cell 40b and located between the first middle region 412 and the second solar cell 40b; the second surface 42 of the second solar cell 40b includes a second edge region 421 and a second middle region 422, the second edge region 421 being adjacent to the first solar cell 40a and located between the second middle region 422 and the first solar cell 40a. The photovoltaic module also includes a solder ribbon 44, which makes electrical contact with a welding portion 43 on the first surface 41 of the first cell 40a and also makes electrical contact with a welding portion 43 on the second surface 42 of the second cell 40b. Specifically, for the same solder ribbon 44, the contact area between at least one welding portion 43 on the first edge region 411 and the solder ribbon 44 is greater than the contact area between the welding portion 43 on the first intermediate region 412 and the solder ribbon 44, and the contact area between at least one welding portion 43 on the second edge region 421 and the solder ribbon 44 is greater than the contact area between the welding portion 43 on the second intermediate region 422 and the solder ribbon 44.

[0124] In some embodiments, the solder strip 44 includes a first widening portion 441 and a first extension portion 442. The first widening portion 441 is electrically connected to at least one solder portion 43 on the second edge region 421. The first extension portion 442 is connected to the first widening portion 441 and extends along a first direction. The width of the first widening portion 441 along the second direction Y is greater than the width of the first extension portion 442 along the second direction Y.

[0125] The first extension 442 makes electrical contact with the welding portion 43 on the second intermediate region 422.

[0126] In some embodiments, the projected area of ​​the weld portion 43 on the second edge region 421 on the second surface 42 is equal to the projected area of ​​the weld portion 43 on the second middle region 222 on the second surface 42. That is, the contact area between at least one weld portion 43 on the second edge region 421 and the solder strip 44 can be increased simply by setting the width of the first widening portion 441 to be larger.

[0127] In some embodiments, at least one welding portion 43 located on the first edge region 411 is a first welding portion 431, and the welding portion 43 located on the first middle region 312 is a second welding portion 432. The orthogonal projection area of ​​the first welding portion 431 on the first surface 31 is greater than the orthogonal projection area of ​​the second welding portion 432 on the first surface 31.

[0128] In some embodiments, the width of the solder strip 44 on the first edge region 411 along the second direction Y is equal to the width of the solder strip 44 on the first intermediate region 422 along the second direction Y. That is, the contact area between the solder portion 43 and the solder strip 44 on the first edge region 411 can be increased simply by increasing the projected area of ​​the first weld portion 431 onto the first surface 41, without increasing the width of a portion of the solder strip 44 on the first edge region 411. This avoids the negative impact on sunlight absorption by the photovoltaic module caused by increasing the width of a portion of the solder strip 44 on the first edge region 411, thereby improving the performance of the photovoltaic module.

[0129] It should be noted that the relevant parameters of the first widened portion 441, the first extended portion 442, the first welded portion 431 and the second welded portion 432 in the embodiments of this disclosure can be referred to the relevant parameters of the first widened portion 241, the first extended portion 242, the first welded portion 231 and the second welded portion 232 in the foregoing embodiments, and will not be repeated here.

[0130] Figure 17 This is a schematic diagram of a fourth partial structure of a photovoltaic module provided in an embodiment of this disclosure. Figure 18 This is a fourth partial top view of a photovoltaic module provided in an embodiment of this disclosure. Figure 19 This is a fourth partial bottom view of a photovoltaic module provided in an embodiment of this disclosure.

[0131] refer to Figures 17 to 19The photovoltaic module includes: a plurality of solar cells 50, each solar cell 50 having a first surface 51 and a second surface 52 facing each other, each of the first surface 51 and the second surface 52 having a plurality of grid lines (not shown) and a welding portion 53 electrically contacting the corresponding grid lines; the plurality of solar cells 50 includes a first solar cell 50a and a second solar cell 50b arranged adjacent to each other, the first surface 51 of the first solar cell 50a and the first surface 51 of the second solar cell 50b having the same orientation; wherein, the first surface 51 of the first solar cell 50a includes a first edge region 511 and a first middle region 512, the first edge region 511 being adjacent to the second solar cell 50b and located between the first middle region 512 and the second solar cell 50b; the second surface 52 of the second solar cell 50b includes a second edge region 521 and a second middle region 522, the second edge region 521 being adjacent to the first solar cell 50a and located between the second middle region 522 and the first solar cell 50a. The photovoltaic module also includes a solder ribbon 54, which makes electrical contact with a welding portion 53 on the first side 51 of the first cell 50a and also makes electrical contact with a welding portion 53 on the second side 52 of the second cell 50b. Specifically, for the same solder ribbon 54, the contact area between at least one welding portion 53 on the first edge region 511 and the solder ribbon 54 is greater than the contact area between the welding portion 53 on the first intermediate region 512 and the solder ribbon 54, and the contact area between at least one welding portion 53 on the second edge region 521 and the solder ribbon 54 is greater than the contact area between the welding portion 53 on the second intermediate region 522 and the solder ribbon 54.

[0132] In some embodiments, at least one welded portion 53 located on the first edge region 511 is a first welded portion 531, and a welded portion 53 located on the first intermediate region 212 is a second welded portion 532. The orthographic projection area of ​​the first welded portion 531 on the first surface 51 is greater than the orthographic projection area of ​​the second welded portion 532 on the first surface 51. At least one welded portion 53 located on the second edge region 521 is a third welded portion 533, and a welded portion 53 located on the second intermediate region 522 is a fourth welded portion 534. The orthographic projection area of ​​the third welded portion 533 on the second surface 52 is greater than the orthographic projection area of ​​the fourth welded portion 534 on the second surface 52.

[0133] In some embodiments, the width of the solder strip 54 on the first edge region 511 along the second direction Y is equal to the width of the solder strip 54 on the first intermediate region 512 along the second direction Y, and the width of the solder strip 54 on the second edge region 321 along the second direction Y is equal to the width of the solder strip 54 on the second intermediate region 522 along the second direction Y.

[0134] Thus, the contact area between the first weld portion 531 and the solder strip 54 on the first edge region 511 can be increased simply by increasing the projected area of ​​the first weld portion 531 on the first surface 31, without increasing the width of the solder strip 54 on the first edge region 511. This avoids the negative impact on the photovoltaic module's absorption of sunlight caused by increasing the width of the solder strip 54 on the first edge region 511, thereby improving the performance of the photovoltaic module. Similarly, the contact area between the third weld portion 533 and the solder strip 54 on the second edge region 521 can be increased simply by increasing the projected area of ​​the third weld portion 533 on the second surface 52, without increasing the width of the solder strip 54 on the second edge region 521. This avoids the negative impact on the photovoltaic module's absorption of sunlight caused by increasing the width of the solder strip 54 on the second edge region 521, thereby improving the performance of the photovoltaic module.

[0135] It should be noted that the relevant parameters of the first welding part 531, the second welding part 532, the third welding part 533 and the fourth welding part 534 in the embodiments of this disclosure can be referred to the relevant parameters of the first welding part 231, the second welding part 232, the third welding part 233 and the fourth welding part 234 in the foregoing embodiments, and will not be repeated here.

[0136] Figure 20 This is a schematic diagram of a fifth partial structure of a photovoltaic module provided in an embodiment of this disclosure. Figure 21 This is a fifth partial top view of a photovoltaic module provided in an embodiment of this disclosure. Figure 22 This is a fifth partial bottom view of a photovoltaic module provided in an embodiment of this disclosure.

[0137] refer to Figures 20 to 22The photovoltaic module includes: a plurality of solar cells 60, each solar cell 60 having a first surface 61 and a second surface 62 facing each other, each of the first surface 61 and the second surface 62 having a plurality of grid lines (not shown) and a welding portion 63 electrically contacting the corresponding grid lines; the plurality of solar cells 60 includes a first solar cell 60a and a second solar cell 60b arranged adjacent to each other, the first surface 61 of the first solar cell 60a and the first surface 61 of the second solar cell 60b having the same orientation; wherein, the first surface 61 of the first solar cell 60a includes a first edge region 611 and a first middle region 612, the first edge region 611 being adjacent to the second solar cell 60b and located between the first middle region 612 and the second solar cell 60b; the second surface 62 of the second solar cell 60b includes a second edge region 621 and a second middle region 622, the second edge region 621 being adjacent to the first solar cell 60a and located between the second middle region 622 and the first solar cell 60a. The photovoltaic module also includes a solder ribbon 64, which makes electrical contact with a welding portion 63 on the first side 61 of the first cell 60a and also makes electrical contact with a welding portion 63 on the second side 62 of the second cell 60b. Specifically, for the same solder ribbon 64, the contact area between at least one welding portion 63 on the first edge region 611 and the solder ribbon 64 is greater than the contact area between the welding portion 63 on the first intermediate region 612 and the solder ribbon 64, and the contact area between at least one welding portion 63 on the second edge region 621 and the solder ribbon 64 is greater than the contact area between the welding portion 63 on the second intermediate region 622 and the solder ribbon 64.

[0138] It should be noted that the battery cell 60, the first edge region 611, the second edge region 621, the first widening portion 641, the first extension portion 642, the second welding portion 632 and the fourth welding portion 634 in the embodiments of this disclosure can refer to the battery cell 20, the first edge region 211, the second edge region 221, the first widening portion 241, the first extension portion 242, the second welding portion 232 and the fourth welding portion 234 in the foregoing embodiments.

[0139] In some embodiments, the first surface 61 of the first battery cell 60a further includes a third edge region 613, which is located away from the second battery cell 60b, and a first intermediate region 612 is located between the third edge region 613 and the first edge region 611; the second surface 62 of the second battery cell 60b further includes a fourth edge region 623, which is located away from the first battery cell 60a, and a second intermediate region 622 is located between the second edge region 621 and the fourth edge region 623; for the same solder strip 64, the contact area between at least one welded portion 63 on the third edge region 613 and the solder strip 64 is greater than the contact area between the welded portion 63 on the first intermediate region 612 and the solder strip 64, and the contact area between at least one welded portion 63 on the fourth edge region 623 and the solder strip 64 is greater than the contact area between the welded portion 63 on the second intermediate region 622 and the solder strip 64. The larger contact area between at least one welded part 63 and the solder strip 64 on the third edge region 613 and the fourth edge region 623 is beneficial to improving the connection strength between at least one welded part 63 and the solder strip 64 on the third edge region 613 and the fourth edge region 623, reducing the risk of poor soldering between the welded part 63 and the solder strip 64 on the third edge region 613 and the fourth edge region 623, thereby improving the performance of the photovoltaic module.

[0140] In some embodiments, for the same solder strip 64, the number of solder portions 63 on the third edge region 613 is less than or equal to 3, and the number of solder portions 63 on the fourth edge region 623 is less than or equal to 3; and / or, in the first direction X, the ratio of the width of the third edge region 613 to the width of the first battery cell 60a is less than or equal to 1 / 4, and the ratio of the width of the fourth edge region 623 to the width of the second battery cell 60b is less than or equal to 1 / 4.

[0141] In some embodiments, the solder strip 64 includes: a first extension 642 and a second widening 643, the second widening 643 being electrically connected to at least one welding portion 63 on a third edge region 613 and electrically contacting at least one welding portion 63 on a fourth edge region 623; the first extension being connected to the second widening 643 and extending along a first direction X; wherein the width of the second widening 643 along a second direction Y is greater than the width of the first extension along the second direction Y.

[0142] In some embodiments, at least one weld portion 63 located on the third edge region 613 is a fifth weld portion 635, and the weld portion 63 located on the first intermediate region 612 is a second weld portion 632. The orthographic projection area of ​​the fifth weld portion 635 on the first surface 61 is greater than the orthographic projection area of ​​the second weld portion 632 on the first surface 61.

[0143] At least one welded part 63 located on the fourth edge region 623 is the sixth welded part 636, and the welded part 63 located on the second intermediate region 622 is the fourth welded part 634. The orthographic projection area of ​​the sixth welded part 636 on the second surface 62 is greater than the orthographic projection area of ​​the fourth welded part 634 on the second surface 62.

[0144] In some embodiments, the projected area of ​​the fifth welded portion 635 on the first surface 61 is 0.675 mm. 2 ~1.44mm 2 For example, 0.675mm 2 0.7mm 2 0.9mm 2 1.1mm 2 1.3mm 2 Or 1.44mm 2 The projected area of ​​the second welded part 632 on the first surface 61 is 0.18 mm². 2 ~0.6mm 2 For example, 0.18mm 2 0.2mm 2 0.3mm 2 0.4mm 2 0.5mm 2 or 0.6mm 2 .

[0145] The projected area of ​​the sixth welded part 636 on the second surface 62 is 0.675 mm². 2 ~1.44mm 2 For example, 0.675mm 2 0.7mm 2 0.9mm 2 1.1mm 2 1.3mm 2 Or 1.44mm 2 The projected area of ​​the fourth welded part 634 on the second surface 62 is 0.18 mm². 2 ~0.6mm 2 For example, 0.18mm 2 0.2mm 2 0.3mm 2 0.4mm 2 0.5mm 2 or 0.6mm 2 .

[0146] In some embodiments, the fifth welding portion 635 includes a third main body portion 6351 and a third gradient portion 6352. The third gradient portion 6352 is connected to the third main body portion 6351 and is located on the side of the third main body portion 6351 near the second solar cell 60b. In the direction from the first solar cell 60a to the second solar cell 60b, the width of the third gradient portion 6352 gradually decreases along the second direction Y. The gradual decrease in the width of the third gradient portion 6352 along the second direction Y can reduce the light-shielding area of ​​the third gradient portion 6352 on the solar cell 60, thereby improving the performance of the photovoltaic module.

[0147] The sixth welding portion 636 includes a fourth main body portion 6361 and a fourth gradient portion 6362. The fourth gradient portion 6362 is connected to the fourth main body portion 6361 and is located on the side of the fourth main body portion 6361 near the first solar cell 60a. In the direction from the second solar cell 60b to the first solar cell 60a, the width of the fourth gradient portion 6362 gradually decreases along the second direction Y. The gradual decrease in the width of the fourth gradient portion 6362 along the second direction Y can reduce the light-shielding area of ​​the fourth gradient portion 6362 on the solar cell 60, thereby improving the performance of the photovoltaic module.

[0148] In some embodiments, the width of the third main body portion 6351 along the first direction X is 0.6mm to 0.8mm, for example 0.6mm, 0.7mm or 0.8mm, and the length of the third main body portion 6351 along the second direction Y is 1mm to 1.2mm, for example 1mm, 1.1mm or 1.2mm.

[0149] The width of the third gradient portion 6352 along the first direction X is 0.3mm to 0.8mm, for example, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm or 0.8mm. The length of the end of the third gradient portion 6352 near the third main body portion 6351 along the second direction Y is 1mm to 1.2mm, for example, 1mm, 1.1mm or 1.2mm.

[0150] The width of the fourth main body 6361 along the first direction X is 0.6mm to 0.8mm, for example 0.6mm, 0.7mm or 0.8mm, and the length of the fourth main body 6361 along the second direction Y is 1mm to 1.2mm, for example 1mm, 1.1mm or 1.2mm.

[0151] The width of the fourth gradient portion 6362 along the first direction X is 0.3mm to 0.8mm, for example, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, or 0.8mm. The length of the end of the fourth gradient portion 6362 near the fourth main body portion 6361 along the second direction Y is 1mm to 1.2mm, for example, 1mm, 1.1mm, or 1.2mm.

[0152] Figure 23 This is a schematic diagram of a fifth welding part provided in an embodiment of the present disclosure.

[0153] refer to Figure 20 and Figure 23 In some embodiments, the third gradient portion 6352 includes a fifth contour line and a sixth contour line. In the direction from the first battery cell 60a to the second battery cell 60b, the distance between the fifth and sixth contour lines along the second direction Y gradually decreases. Both the fifth and sixth contour lines are arcs. In the direction from the first battery cell 60a to the second battery cell 60b, the absolute value of the slope of both the fifth and sixth contour lines gradually decreases. The distance between the fifth and sixth contour lines along the second direction Y is the width of the third gradient portion 6352 along the second direction Y. Compared to a scheme where the fifth and sixth contour lines are straight lines, the gradual decrease in the absolute value of the slope of both contour lines ensures sufficient contact area between the solder ribbon 64 and the third gradient portion 6352 while saving material in the third gradient portion 6352.

[0154] Figure 24 This is a schematic diagram of a sixth welding part provided in an embodiment of the present disclosure.

[0155] refer to Figure 21 and Figure 24 The fourth gradient section 6362 includes a seventh contour line and an eighth contour line. In the direction from the second battery cell 60b to the first battery cell 60a, the distance between the seventh and eighth contour lines along the second direction Y gradually decreases. Both the seventh and eighth contour lines are arcs. In the direction from the second battery cell 60b to the first battery cell 60a, the absolute value of the slope of both the seventh and eighth contour lines gradually decreases. The distance between the seventh and eighth contour lines along the second direction Y is the width of the fourth gradient section 6362 along the second direction Y. Compared to a scheme where the seventh and eighth contour lines are straight lines, the gradual decrease in the absolute value of the slope of both contour lines ensures sufficient contact area between the solder ribbon 64 and the fourth gradient section 6362 while saving material in the fourth gradient section 6362.

[0156] Continue to refer to Figures 20 to 22In this embodiment, by setting a larger width for the solder strip 64 in the third edge region 613 and increasing the projected area of ​​the weld portion 63 on the first surface 61, the contact area between at least one weld portion 63 on the third edge region 613 and the solder strip 64 is made greater than the contact area between the weld portion 63 on the first intermediate region 612 and the solder strip 64. It is understood that in other embodiments, simply setting a larger width for the solder strip 64 in the third edge region 613, or simply increasing the projected area of ​​the weld portion 63 on the first surface 61, can make the contact area between at least one weld portion 63 on the third edge region 613 and the solder strip 64 greater than the contact area between the weld portion 63 on the first intermediate region 612.

[0157] Similarly, in this embodiment, by setting the width of the solder strip 64 in the fourth edge region 623 to be larger and increasing the orthogonal projection area of ​​the weld portion 63 on the first surface 61 in the fourth edge region 623, the contact area between at least one weld portion 63 on the fourth edge region 623 and the solder strip 64 is made greater than the contact area between the weld portion 63 on the first intermediate region 612 and the solder strip 64. It is understood that in other embodiments, simply setting the width of the solder strip 64 in the fourth edge region 623 to be larger, or simply increasing the orthogonal projection area of ​​the weld portion 63 on the first surface 61 in the fourth edge region 623, can make the contact area between at least one weld portion 63 on the fourth edge region 623 and the solder strip 64 greater than the contact area between the weld portion 63 on the second intermediate region 622 and the solder strip 64.

[0158] Those skilled in the art will understand that the above embodiments are specific examples of implementing this disclosure, and in practical applications, various changes in form and detail may be made without departing from the spirit and scope of this disclosure. Any person skilled in the art can make various alterations and modifications without departing from the spirit and scope of this disclosure; therefore, the scope of protection of this disclosure should be determined by the scope defined in the claims.

Claims

1. A photovoltaic module, characterized by, include: A plurality of battery cells are provided, each battery cell including a first side and a second side facing each other. Both the first side and the second side are provided with multiple grid lines and welding portions electrically contacting the corresponding grid lines. The plurality of battery cells include first battery cells and second battery cells arranged adjacent to each other, with the first side of the first battery cell and the first side of the second battery cell facing the same direction. The first side of the first battery cell includes a first edge region and a first middle region, the first edge region being adjacent to the second battery cell and located between the first middle region and the second battery cell. The second side of the second battery cell includes a second edge region and a second middle region, the second edge region being adjacent to the first battery cell and located between the second middle region and the first battery cell. The welding strip is in electrical contact with the welding portion on the first surface of the first battery cell, and also in electrical contact with the welding portion on the second surface of the second battery cell; Specifically, for the same weld strip, the contact area between at least one welded portion on the first edge region and the weld strip is greater than the contact area between the welded portion on the first intermediate region and the weld strip, and the contact area between at least one welded portion on the second edge region and the weld strip is greater than the contact area between the welded portion on the second intermediate region and the weld strip.

2. The photovoltaic module of claim 1, wherein, The welding strip includes: A first widening portion, the first widening portion being electrically connected to at least one of the welded portions on the first edge region, and / or, The first widened portion is in electrical contact with at least one of the welded portions on the second edge region; A first extension portion, which is connected to the first widened portion and extends along a first direction; Wherein, the width of the first widened portion along the second direction is greater than the width of the first extended portion along the second direction.

3. The photovoltaic module of claim 2, wherein, The thickness of the first widened portion is less than the thickness of the first extended portion.

4. The photovoltaic module of claim 2, wherein, The width of the first widened portion along the second direction is 0.4mm to 0.8mm, and the width of the first extended portion along the second direction is 0.20mm to 0.28mm.

5. The photovoltaic module of claim 2, wherein, The first widened portion is electrically connected to at least one of the welded portions on the first edge region, and the first widened portion is electrically in contact with at least one of the welded portions on the second edge region. The orthographic projection area of ​​the welded portion on the first edge region on the first surface is equal to the orthographic projection area of ​​the welded portion on the first middle region on the first surface, and the orthographic projection area of ​​the welded portion on the second edge region on the second surface is equal to the orthographic projection area of ​​the welded portion on the second middle region on the second surface.

6. The photovoltaic module of claim 1 or 2, wherein, At least one of the welded portions located on the first edge region is a first welded portion, and the welded portion located on the first middle region is a second welded portion. The orthographic projection area of ​​the first welded portion on the first surface is greater than the orthographic projection area of ​​the second welded portion on the first surface. And / or, At least one of the welded portions located on the second edge region is a third welded portion, and the welded portion located on the second middle region is a fourth welded portion. The orthographic projection area of ​​the third welded portion on the second surface is greater than the orthographic projection area of ​​the fourth welded portion on the second surface.

7. The photovoltaic module of claim 6, wherein, The projected area of ​​the first welded portion on the first surface is 0.675 mm². 2 ~1.44mm 2 The projected area of ​​the second welded part on the first surface is 0.18 mm. 2 ~0.6mm 2 The projected area of ​​the third welded portion on the second surface is 0.675 mm². 2 ~1.44mm 2 The projected area of ​​the fourth welded part on the second surface is 0.18 mm. 2 ~0.6mm 2 .

8. The photovoltaic module of claim 6, wherein, The first welded portion includes: a first main body portion and a first gradient portion, the first gradient portion being connected to the first main body portion and located on the side of the first main body portion opposite to the second battery cell, and the width of the first gradient portion gradually decreasing along a second direction in the direction from the second battery cell to the first battery cell; and / or, The third welding portion includes: a second main body portion and a second gradient portion. The second gradient portion is connected to the second main body portion and is located on the side of the second main body portion away from the first battery cell. In the direction from the first battery cell to the second battery cell, the width of the first gradient portion gradually decreases along the second direction.

9. The photovoltaic module of claim 8, wherein, The first gradient section includes a first contour line and a second contour line. In the direction from the second battery cell to the first battery cell, the distance between the first contour line and the second contour line along the second direction gradually decreases. The first contour line is an arc, and the second contour line is an arc. In the direction from the second battery cell to the first battery cell, the absolute value of the slope of the first contour line gradually decreases, and the absolute value of the slope of the second contour line gradually decreases; and / or, The second gradient section includes a third contour line and a fourth contour line. In the direction from the first battery cell to the second battery cell, the distance between the third contour line and the fourth contour line along the second direction gradually decreases. The third contour line is an arc, and the fourth contour line is an arc. In the direction from the first battery cell to the second battery cell, the absolute value of the slope of the third contour line gradually decreases, and the absolute value of the slope of the fourth contour line gradually decreases.

10. The photovoltaic module of claim 8, wherein, The width of the first main body portion along the first direction is 0.6mm to 0.8mm, and the length of the first main body portion along the second direction is 1mm to 1.2mm. The width of the first gradient portion along the first direction is 0.3mm to 0.8mm, and the length of the end of the first gradient portion near the first main body portion along the second direction is 1mm to 1.2mm. The width of the second main body portion along the first direction is 0.6mm to 0.8mm, and the length of the second main body portion along the second direction is 1mm to 1.2mm. The width of the second gradient portion along the first direction is 0.3mm to 0.8mm, and the length of the end of the second gradient portion near the second main body portion along the second direction is 1mm to 1.2mm.

11. The photovoltaic module of claim 1, wherein, For the same solder strip, the contact area between the solder portion adjacent to the second battery cell on the first edge region and the solder strip is greater than the contact area between the solder portion and the solder strip on the first middle region; the contact area between the solder portion adjacent to the first battery cell on the second edge region and the solder strip is greater than the contact area between the solder portion and the solder strip on the second middle region.

12. The photovoltaic module of claim 1, wherein, The battery cell also includes a cut surface and a non-cut surface arranged opposite to each other, with the non-cut surface of the first battery cell facing the cut surface of the second battery cell.

13. The photovoltaic module of claim 1, wherein, For the same weld strip, the number of welded portions on the first edge region is less than or equal to 3, and the number of welded portions on the second edge region is less than or equal to 3; and / or, In the first direction, the ratio of the width of the first edge region to the width of the first battery cell is less than or equal to 1 / 4, and the ratio of the width of the second edge region to the width of the second battery cell is less than or equal to 1 / 4.

14. The photovoltaic module of claim 1, wherein, The first side of the first battery cell further includes: a third edge region, the third edge region being away from the second battery cell, and the first middle region being located between the third edge region and the first edge region; The second side of the second battery cell further includes: a fourth edge region, the fourth edge region being away from the first battery cell, and the second middle region being located between the second edge region and the fourth edge region; For the same weld strip, the contact area between at least one welded portion on the third edge region and the weld strip is greater than the contact area between the welded portion on the first intermediate region and the weld strip, and the contact area between at least one welded portion on the fourth edge region and the weld strip is greater than the contact area between the welded portion on the second intermediate region and the weld strip.

15. The photovoltaic module of claim 14, wherein, The welding strip includes: The second widening portion is electrically connected to at least one of the welded portions on the third edge region, and / or the second widening portion is electrically in contact with at least one of the welded portions on the fourth edge region; A first extension portion, which is connected to the second widened portion and extends along a first direction; Wherein, the width of the second widened portion along the second direction is greater than the width of the first extended portion along the second direction.

16. The photovoltaic module of claim 14 or 15, wherein, At least one of the welded portions located on the third edge region is a fifth welded portion, and the welded portion located on the first middle region is a second welded portion. The orthographic projection area of ​​the fifth welded portion on the first surface is greater than the orthographic projection area of ​​the second welded portion on the first surface. And / or, At least one of the welded portions located on the fourth edge region is a sixth welded portion, and the welded portion located on the second middle region is a fourth welded portion. The orthographic projection area of ​​the sixth welded portion on the second surface is greater than the orthographic projection area of ​​the fourth welded portion on the second surface.

Images