Photovoltaic module
By designing solder strips of varying widths in photovoltaic modules, the problem of buffer components affecting connection reliability was solved, achieving stable connection between the cells and solder strips and improving the performance of photovoltaic modules, while also reducing manufacturing costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- JINKO SOLAR (HAINING) CO LTS
- Filing Date
- 2025-10-22
- Publication Date
- 2026-07-31
AI Technical Summary
The inclusion of a buffer component affects the reliability of the connection between the first solar cell and the solder strip, leading to performance and manufacturing cost issues for the photovoltaic module.
In photovoltaic modules, the solder strip is designed to include a first part and a second part. The first part is located on the cell adjacent to the buffer and is wider than the second part. The second part is wider than the grid lines away from the buffer, which enhances the contact area and connection strength while reducing the shading area.
This improved the reliability of the connection between the solar cells and the solder ribbon, enhanced the performance of the photovoltaic module, and saved manufacturing costs.
Smart Images
Figure CN122497121A_ABST
Abstract
Description
Cross-reference to related applications
[0001] This disclosure is a divisional application of Chinese patent application No. 202511517447.0, filed on October 22, 2025, entitled "Photovoltaic Module". Technical Field
[0002] This disclosure relates to the photovoltaic field, and in particular to a photovoltaic module. Background Technology
[0003] 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.
[0004] Photovoltaic modules are crucial devices for converting solar energy into electrical energy. A photovoltaic module comprises multiple cell strings, each containing multiple adjacent first and second cells, with the second cells overlapping the first cells. To reduce the interaction force between the first and second cells, a buffer is placed in the overlap area to act as a cushion. However, the inclusion of this buffer introduces certain problems, affecting the reliability of the connection between the first cells and the solder strip. Summary of the Invention
[0005] This disclosure provides a photovoltaic module that can at least improve the connection reliability between the solar cells and the solder ribbon, enhance the performance of the photovoltaic module, and save on the manufacturing cost of the photovoltaic module.
[0006] According to some embodiments of this disclosure, this disclosure provides a photovoltaic module, which includes a plurality of cell strings, each cell string including a plurality of cells arranged along a first direction and solder strips electrically connecting adjacent cells. Each cell has a first grid line extending along a second direction, and the solder strips are electrically connected to the first grid line. The plurality of cells include adjacent first and second cells, with the second cell overlapping the first cell. A buffer is provided, located in the overlap area between the first and second cells, and at least a portion of the buffer is located between the first cell and the solder strips. The solder strips include a first portion and a second portion, the first portion being located on the first cell and adjacent to the buffer, and the width of the first portion being greater than the width of the second portion along the second direction.
[0007] In some embodiments, on the first cell, the first grid line near the buffer includes a first portion and a second portion that is in electrical contact with the solder strip.
[0008] In some embodiments, along the first direction, the width of the second portion is greater than the width of the first gate line away from the buffer.
[0009] In some embodiments, the width of the second part is greater than or equal to the width of the first part along the first direction.
[0010] In some embodiments, along the first direction, the width of the second part is 0.06 mm to 0.08 mm, and the width of the first grid line away from the buffer is 0.01 mm to 0.05 mm.
[0011] In some embodiments, the height of the surface of the second part away from the first battery cell relative to the first battery cell is a first height, and the height of the first grid line away from the surface of the first battery cell relative to the first battery cell is a second height, wherein the first height is greater than the second height.
[0012] In some embodiments, the height of the surface of the first part facing away from the first battery cell relative to the first battery cell is a third height, and the first height is greater than or equal to the third height.
[0013] In some embodiments, the first height is 13μm~17μm, and the second height is 8μm~12μm.
[0014] In some embodiments, the battery cell further has a second grid line, the second grid line including a main body extending along the first direction and a forked structure located at both ends of the main body, the forked structure including two branches, wherein at least a portion of the second part is located between the two branches.
[0015] In some embodiments, the battery cell further has a second grid line extending along a first direction, the second grid line on the first battery cell including a third portion and a fourth portion near the buffer, the fourth portion being in electrical contact with the second portion, wherein, along the second direction, the width of the fourth portion is greater than the width of the third portion.
[0016] In some embodiments, along the second direction, the width of the third part is 0.02mm to 0.1mm, and the width of the fourth part is 0.1mm to 0.3mm.
[0017] In some embodiments, the height of the surface of the fourth part away from the first battery cell relative to the first battery cell is a fourth height, and the height of the surface of the third part away from the first battery cell relative to the first battery cell is a fifth height, wherein the fourth height is greater than the fifth height.
[0018] In some embodiments, the fourth height is 14μm~18μm, and the fifth height is 10μm~14μm.
[0019] In some embodiments, the thickness of the buffer is 0.01 mm to 0.03 mm.
[0020] The technical solutions provided in this disclosure have at least the following advantages: In the photovoltaic module technical solution provided in this disclosure, the solder strip includes a first part and a second part. The first part is located on the first solar cell and adjacent to a buffer. Along the second direction, the width of the first part is greater than the width of the second part. The larger width of the first part increases the contact area between the first part and the first grid line, thereby improving the connection strength between the first part and the first grid line, and thus improving the connection reliability between the first solar cell and the solder strip. The smaller width of the second part reduces the shading area of the second part on the solar cell, thereby improving the performance of the photovoltaic module. The smaller width of the second part also helps to save on the manufacturing cost of the photovoltaic module. Attached Figure Description
[0021] 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.
[0022] Figure 1 This is a schematic diagram of a partial structure of a photovoltaic module in related technologies; Figure 2 A top view of the first solar cell and buffer in a photovoltaic module in related technologies; Figure 3 A schematic diagram of a first and second solar cell in a photovoltaic module provided in this embodiment of the present disclosure; Figure 4 A top view of the first solar cell and buffer in a photovoltaic module provided in this embodiment of the present disclosure; Figure 5 A bottom view of the second solar cell and buffer in a photovoltaic module provided in an embodiment of this disclosure; Figure 6 This is a schematic diagram of another structure of the first and second solar cells in a photovoltaic module provided in this embodiment of the present disclosure; Figure 7 For along Figure 4A cross-sectional view along the A1-A2 direction; Figure 8 A cross-sectional view of the first grid line near the buffer in a photovoltaic module provided in an embodiment of this disclosure; Figure 9 This is a schematic diagram of the structure of a first solar cell in a photovoltaic module provided in an embodiment of this disclosure; Figure 10 This is a schematic diagram of a structure of the second grid line in a photovoltaic module provided in an embodiment of the present disclosure; Figure 11 This is a schematic diagram of another structure of the first cell in a photovoltaic module provided in this embodiment of the present disclosure; Figure 12 This is a schematic diagram of another structure of the second grid line in a photovoltaic module provided in an embodiment of this disclosure; Figure 13 This is a cross-sectional view of the second grid line in a photovoltaic module provided in an embodiment of the present disclosure; Figure 14 This is a schematic diagram of a structure of a first solar cell and a solder strip in a photovoltaic module provided in an embodiment of the present disclosure; Figure 15 This is a schematic diagram of a structure of the solder strip in a photovoltaic module provided in an embodiment of the present disclosure; Figure 16 This is a partial structural schematic diagram of a photovoltaic module provided in an embodiment of the present disclosure.
[0023] Explanation of reference numerals in the attached figures: 10. Battery substrate; 101. First battery substrate; 102. Second battery substrate; 11. Conductive strip; 111. First electrical contact portion; 112. Second electrical contact portion; 113. Connecting portion; 12. Electrode; 13. Buffer portion; 20. Battery cell; 201. First battery cell; 202. Second battery cell; 203. First surface; 204. Second surface; 21. Solder strip; 211. First electrical contact portion; 212. Second electrical contact portion; 213. Connecting portion; 214. First part; 215. Second part; 22. First grid line; 221. First part; 222. Second part; 23. Buffer element; 24. Second grid line; 241. Main body; 242. Forked structure; 2421. Support fork; 243. Blank area; 244. Third part; 245. Fourth part; 25. Encapsulating film; 26. Cover plate. Detailed Implementation
[0024] Figure 1 This is a schematic diagram of a partial structure of a photovoltaic module in related technologies. Figure 2 This is a top view of the first cell substrate and buffer section in a photovoltaic module according to related technologies. Figure 1 The electrodes are not shown in the diagram.
[0025] refer to Figure 1 and Figure 2 The photovoltaic module in the related technology includes multiple cell strings, each cell string including multiple cell substrates 10 arranged along a first direction X and conductive strips 11 electrically connecting adjacent cell substrates 10. Each cell substrate 10 has electrodes 12 extending along a second direction Y, and the conductive strips 11 are electrically connected to the electrodes 12. The multiple cell substrates 10 include adjacent first cell substrates 101 and second cell substrates 102, with the second cell substrate 102 overlapping the first cell substrate 101. The photovoltaic module also includes a buffer portion 13 located in the overlap area between the first cell substrate 101 and the second cell substrate 102, and at least a portion of the buffer portion 13 is located between the first cell substrate 101 and the conductive strip 11.
[0026] On the first battery substrate 101, the electrode 12 near the buffer portion 13 includes a first portion (not identified) and a second portion (not identified) that is in electrical contact with the conductive strip 11.
[0027] In related technologies, the widths of the multiple electrodes 12 on the first battery substrate 101 along the first direction X are generally equal. That is, along the first direction X, the width of the second part is equal to the width of the electrode 12 away from the buffer part 13, and the width of the second part is equal to the width of the first part.
[0028] The conductive strip 11 may include a first electrical contact portion 111 and a second electrical contact portion 112 spaced apart, and a connecting portion 113 located between the first electrical contact portion 111 and the second electrical contact portion 112. The first electrical contact portion 111 is in electrical contact with the first battery substrate 101. The second electrical contact portion 112 is in electrical contact with the second battery substrate 102. The connecting portion 113 is located on the side wall of the buffer portion 13 and connects the first electrical contact portion 111 and the second electrical contact portion 112.
[0029] The buffer portion 13 has a certain thickness, which causes the second electrical contact portion 112 and the connecting portion 113 to exert a pulling force on the first electrical contact portion 111 that contacts the second portion. Furthermore, in related technologies, the width of the second portion is equal to the width of the electrode 12 furthest from the buffer portion 13, meaning the width of the second portion is small, resulting in a weak connection strength between the second portion and the first electrical contact portion 111. Therefore, in photovoltaic modules of related technologies, under the pulling force of the second electrical contact portion 112 and the connecting portion 113 on the first electrical contact portion 111, there is a risk of the second portion detaching from the first electrical contact portion 111, leading to low reliability of the connection between the first battery substrate 101 and the conductive strip 11.
[0030] Therefore, this disclosure provides a photovoltaic module in which the width of the second portion is greater than the width of the first grid line away from the buffer member. Thus, the larger width of the second portion near the first grid line in the buffer member, which is in electrical contact with the solder strip, improves the connection strength between the second portion and the solder strip. This prevents the second portion from detaching from the solder strip due to insufficient connection strength, especially from the portion of the solder strip located on the buffer member away from the first solar cell and the portion located on the sidewall of the buffer member, thus affecting the connection reliability between the first solar cell and the solder strip. In other words, a larger width of the second portion improves the connection reliability between the first solar cell and the solder strip.
[0031] Furthermore, along the first direction, the width of the second part is greater than the width of the first grid line farther from the buffer member. The smaller width of the first grid line farther from the buffer member results in a smaller shading area of the first grid line on the first solar cell, which is beneficial for improving the performance of the photovoltaic module. The smaller width of the first grid line farther from the buffer member also helps to reduce the manufacturing cost of the photovoltaic module.
[0032] In the photovoltaic module technical solution disclosed herein, the first part has a larger width, which increases the contact area between the first part and the first grid line, thereby improving the connection strength between the first part and the first grid line, and thus improving the connection reliability between the first cell and the solder ribbon. The second part has a smaller width, which reduces the shading area of the second part on the cell, thereby improving the performance of the photovoltaic module. The smaller width of the second part also helps to save on the manufacturing cost of the photovoltaic module.
[0033] 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.
[0034] 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.
[0035] 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.
[0036] In the description of embodiments of this disclosure, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).
[0037] 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.
[0038] In the description of the embodiments of this disclosure, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this disclosure according to the specific circumstances.
[0039] In the description of the embodiments disclosed herein, an electrical connection between one component and another means that both components are made of conductive materials and are directly connected or connected via other conductive materials, so that current flows between the two components when the photovoltaic module is generating electricity. An electrical contact between one component and another means that the two components are not only in contact, but also, because both components are made of conductive materials, current flows between them when the photovoltaic module is generating electricity.
[0040] 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.
[0041] 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.
[0042] 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.
[0043] Figure 3 This is a schematic diagram of the structure of the first and second solar cells in a photovoltaic module provided in an embodiment of this disclosure. Figure 4 This is a top view of the first solar cell and buffer in a photovoltaic module provided in an embodiment of this disclosure. Figure 5 This is a bottom view of the second solar cell and buffer in a photovoltaic module provided in an embodiment of this disclosure. Figure 3 The first grid line is not shown in the diagram.
[0044] refer to Figures 3 to 5 The photovoltaic module includes multiple cell strings, each cell string including multiple cells 20 arranged along a first direction X and solder ribbons 21 electrically connecting adjacent cells 20. Each cell 20 has a first grid line 22 extending along a second direction Y. The solder ribbons 21 are electrically connected to the first grid line 22. The multiple cells 20 include adjacent first cells 201 and second cells 202, with the second cells 202 overlapping the first cells 201. The photovoltaic module also includes a buffer 23 located in the overlapping area between the first cells 201 and the second cells 202, and at least a portion of the buffer 23 is located between the first cells 201 and the solder ribbons 21. Specifically, on the first cells 201, the first grid line 22 near the buffer 23 includes a first portion 221 and a second portion 222 electrically in contact with the solder ribbons 21. Along the first direction X, the width of the second portion 222 is greater than the width of the first grid line 22 away from the buffer 23.
[0045] Photovoltaic modules are used to convert solar energy into electrical energy.
[0046] 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.
[0047] The battery cell 20 can be a whole cell or a sliced cell. A sliced cell refers to a cell formed by cutting a complete cell. Sliced cells can be two-piece sliced cells, three-piece sliced cells, or four-piece sliced cells, etc.
[0048] The battery cell 20 has a first surface 203 and a second surface 204 that are disposed opposite to each other.
[0049] Figure 6 This is a schematic diagram of another structure of the first and second solar cells in a photovoltaic module provided in an embodiment of this disclosure.
[0050] When the battery cell is a back-contact battery, there is no first grid line on the first surface, and the first grid line is only present on the second surface. (Reference) Figure 6 When the battery cells are in back contact, the orientation of the first surface 203 of the first battery cell 201 is opposite to the orientation of the first surface 203 of the second battery cell 202. The solder ribbon 21 is located between the second surface 204 of the first battery cell 201 and the second surface 204 of the first battery cell 202.
[0051] refer to Figure 3 and Figure 4 When the battery cell 20 is a battery other than a back-contact battery, such as a TOPCON battery, first grid lines 22 are provided on both the first surface 203 and the second surface 204, and in the battery string, the orientation of the first surface 203 of the first battery cell 201 is the same as the orientation of the first surface 203 of the second battery cell 202. A solder ribbon 21 is located between the first surface 203 and the second surface 204 of the first battery cell 201. Figure 3 and Figure 4 Using cell 20 as an example, we have a TOPCON battery.
[0052] The solder strip 21 extends along the first direction X and is used to electrically connect the first battery cell 201 and the second battery cell 202.
[0053] The welding strip 21 may include a first electrical contact portion 211 and a second electrical contact portion 212 spaced apart, and a connecting portion 213 located between the first electrical contact portion 211 and the second electrical contact portion 212. The first electrical contact portion 211 is in electrical contact with the first battery cell 201. The second electrical contact portion 212 is in electrical contact with the second battery cell 202. The connecting portion 213 is located on the side wall of the buffer member 23 and connects the first electrical contact portion 211 and the second electrical contact portion 212.
[0054] In some embodiments, during the fabrication of the photovoltaic module, firstly, a first solar cell 201 and a second solar cell 202 are electrically connected using solder ribbon 21 to form a cell string. Then, a buffer member 23 is inserted into the overlapping area of the first solar cell 201 and the second solar cell 202, such that at least part of the buffer member 23 is located in the overlapping area. The solder ribbon 21 itself has a certain degree of flexibility, so that after the buffer member 23 is inserted, the solder ribbon 21 can still make electrical contact with the first solar cell 201 and the second solar cell 202. Furthermore, the insertion of the buffer member 23 causes a pulling force between the second electrical contact portion 212 and the connecting portion 213 on the first electrical contact portion 211.
[0055] At least a portion of the buffer 23 is located in the overlapping area of the first battery cell 201 and the second battery cell 202 to buffer the force exerted by the first battery cell 201 and the second battery cell 202 in the overlapping area.
[0056] In some embodiments, the thickness of the buffer 23 is 0.01 mm to 0.03 mm, for example, 0.01 mm, 0.015 mm, 0.02 mm, 0.025 mm, or 0.03 mm. The thickness of the buffer 23 is within the above range, which can provide sufficient cushioning for the first battery cell 201 and the second battery cell 202.
[0057] The first gate line 22 is a fine gate. The first gate line 22 is used to collect photogenerated carriers and transfer them to the solder strip 21.
[0058] It should be noted that, Figure 4 The diagram illustrates four first grid lines 22 near the buffer member 23, each including a wider second portion 222. In reality, the number of first grid lines near the buffer member that include a wider second portion can be any number other than four, such as 1, 2, 3, or 5.
[0059] In some embodiments, along the first direction X, the width of the second portion 222 is greater than or equal to the width of the first portion 221. When the width of the second portion 222 is equal to the width of the first portion 221, the width of the entire first grid line 22 near the buffer member 23 is the same, which facilitates the fabrication of the first grid line 22 and improves the fabrication efficiency of the first grid line 22. When the width of the second portion 222 is greater than the width of the first portion 221, the larger width of the second portion 222 can improve the connection strength between the second portion 222 and the solder ribbon 21, and the smaller width of the first portion 221 can reduce the shading area of the first portion 221 on the first solar cell 201, which is beneficial to improving the performance of the photovoltaic module. In addition, the smaller width of the first portion 221 can also save the fabrication cost of the first portion 221.
[0060] In some embodiments, the width of the first portion 221 along the first direction X is 0.01mm to 0.08mm, for example 0.01mm, 0.02mm, 0.03mm, 0.04mm, 0.05mm, 0.06mm, 0.07mm or 0.08mm.
[0061] In some embodiments, the width of the second portion 222 along the first direction X is 0.06 mm to 0.08 mm, for example, 0.06 mm, 0.065 mm, 0.07 mm, 0.075 mm, or 0.08 mm. A wider width within the above range can improve the connection strength between the second portion 222 and the first electrical contact portion 211, thereby improving the connection reliability between the first battery cell 201 and the solder ribbon 21.
[0062] Along the first direction X, the width of the first grid line 22, away from the buffer member 23, is 0.03mm to 0.05mm, for example, 0.03mm, 0.035mm, 0.04mm, 0.045mm, or 0.05mm. The smaller width of the first grid line 22 away from the buffer member 23 results in a smaller shading area of the first grid line 22 on the first solar cell 201, which is beneficial for improving the performance of the photovoltaic module. The smaller width of the first grid line 22 away from the buffer member 23 also helps to reduce the manufacturing cost of the photovoltaic module.
[0063] In some embodiments, the length of the second portion 222 along the second direction Y is 1 mm to 1.5 mm, for example, 1 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, or 1.5 mm. The length of the second portion 222 is within the above range, ensuring that even if the solder strip 21 is offset in the second direction Y due to processing errors when soldering the solder strip 21 to the first gate line 22, it can still make electrical contact with the second portion 222.
[0064] Figure 7 For along Figure 4 A cross-sectional view along the A1-A2 direction. Figure 7 This is a cross-sectional view showing the first grid line 22 near the buffer member 23 and the first grid line 22 away from the buffer member 23.
[0065] refer to Figure 3 , Figure 4 and Figure 7 In some embodiments, the surface of the second part 222 facing away from the first battery cell 201 is at a first height H1 relative to the first battery cell 201, and the surface of the first grid line 22 away from the buffer member 23 is at a second height H2 relative to the first battery cell 201, with the first height H1 being greater than the second height H2. Under the pulling action of the second electrical contact part 212 and the connecting part 213, the portion of the solder ribbon 21 on the first battery cell 201 near the buffer member 23 may be lifted, meaning that there may be a certain distance between the portion of the solder ribbon 21 near the buffer member 23 and the first battery cell 201 in the thickness direction of the battery cell 20. Setting the first height H1 to be greater than the second height H2, i.e., the first height H1 of the second part 222 being larger, ensures that even if the portion of the solder ribbon 21 near the buffer member 23 is lifted, the second part 222 can still make electrical contact with the first electrical contact part 211, thereby improving the connection reliability between the first battery cell 201 and the solder ribbon 21. In addition, the smaller second height H2 of the first grid line 22, which is farther away from the buffer member 23, can prevent the second height H2 from being too large and affecting the absorption of sunlight by the first solar cell 201. Moreover, the smaller second height H2 also helps to save on the manufacturing cost of the first grid line 22.
[0066] Figure 8 This is a cross-sectional view of the first grid line near the buffer in a photovoltaic module provided in an embodiment of the present disclosure.
[0067] refer to Figure 3 , Figure 4 and Figure 8 In some embodiments, the height of the surface of the first part 221 facing away from the first solar cell 201 relative to the first solar cell 201 is a third height H3, where the first height H1 is greater than or equal to the third height H3. When the first height H1 is equal to the third height H3, it facilitates the fabrication of the first grid line 22 and improves the fabrication efficiency of the first grid line 22. When the first height H1 is greater than the third height H3, the third height H3 is smaller, which can prevent the third height H3 from being too high and affecting the absorption of sunlight by the first solar cell 201. Moreover, a smaller third height H3 also helps to save on the manufacturing cost of photovoltaic modules.
[0068] Continue to refer to Figure 3 , Figure 4 , Figure 7 and Figure 8In some embodiments, the first height H1 is 13μm to 17μm, for example, 13μm, 14μm, 15μm, 16μm or 17μm. The first height H1 is within the above range. The first height H1 is relatively large, so that even if the part of the solder ribbon 21 close to the buffer 23 is raised under the pulling action of the connecting part 213 and the second electrical contact part 212, the second part 222 can still make electrical contact with the first electrical contact part 211, thereby improving the connection reliability between the first battery cell 201 and the solder ribbon 21.
[0069] The second height H2 is 8μm to 12μm, for example, 8μm, 9μm, 10μm, 11μm, or 12μm. A smaller second height H2 within this range avoids an excessively large second height H2, which could affect the absorption of sunlight by the first solar cell 201. Furthermore, a smaller second height H2 also helps to reduce the fabrication cost of the first grid line 22.
[0070] In some embodiments, the third height H3 is 8μm to 17μm, for example 8μm, 9μm, 10μm, 11μm, 12μm, 13μm, 14μm, 15μm, 16μm or 17μm.
[0071] In some embodiments, the solar cell 20 can be a gridless solar cell. The solder ribbon 21 achieves electrical connection between the first solar cell 201 and the second solar cell 202 by being electrically connected to the fine grid.
[0072] Figure 9 This is a schematic diagram of the structure of the first cell in a photovoltaic module provided in an embodiment of this disclosure.
[0073] refer to Figure 3 and Figure 9 In some embodiments, the solar cell 20 can be a solar cell with a main grid. The solar cell 20 also has a second grid line 24 electrically connected to the first grid line 22. The second grid line 24 is the main grid, and the second grid line 24 can collect the photogenerated carriers collected by the first grid line 22 and transfer them to the solder ribbon 21.
[0074] Figure 10 This is a schematic diagram of a structure of the second grid line in a photovoltaic module provided in an embodiment of this disclosure.
[0075] refer to Figure 3 , Figure 4 , Figure 9 and Figure 10 In some embodiments, the battery cell 20 also has a second grid line 24, the second grid line 24 including a main body portion 241 extending along a first direction X and a forked structure 242 located at both ends of the main body portion 241, the forked structure 242 including two branches 2421, wherein at least a portion of the second part 222 is located between the two branches 2421.
[0076] The main body 241 is in electrical contact with the welding strip 21.
[0077] The bifurcated structure 242 can increase the contact area between the second gate line 24 and the first gate line 22, thereby improving the efficiency of the second gate line 24 in collecting the current collected by the first gate line 22.
[0078] When the solder ribbon 21 is electrically connected to the first battery cell 201, the solder ribbon 21 will be located between the two forks 2421.
[0079] The fork 2421 can be electrically connected to the second part 222, and the second part 222 has a larger width along the first direction X, which can increase the contact area between the fork 2421 and the second part 222, which is beneficial to improving the efficiency of the fork 2421 in collecting the current collected by the second part 222.
[0080] In some embodiments, a blank area 243 exists near the edge of the first solar cell 201 on the two forks 2421. The blank area 243 contains neither the first grid line 22 nor the second grid line 24, which improves the flatness of the blank area 243 after it is connected to the solder ribbon 21. This prevents stress concentration in the blank area 243 from causing cracks in the first solar cell 201 due to the grid lines on the blank area 243 connecting to the solder ribbon 21, thereby improving the reliability of the photovoltaic module.
[0081] In some embodiments, the width of the blank area 243 along the first direction X is greater than or equal to the width of the overlap area along the first direction X. Thus, there is no first grid line 22 electrically connected to the solder strip 21 between the two prongs 2421 in the overlap area, so that the buffer 23 can be inserted between the first battery cell 201 and the solder strip 21 in the overlap area.
[0082] Figure 11 This is a schematic diagram of another structure of the first cell in the photovoltaic module provided in this embodiment of the present disclosure. Figure 12 This is a schematic diagram of another structure of the second grid line in a photovoltaic module provided in an embodiment of this disclosure.
[0083] refer to Figure 3 , Figure 4 , Figure 11 and Figure 12In some embodiments, the solar cell 20 further includes a second grid line 24 extending along a first direction X. The second grid line 24 on the first solar cell 201 includes a third portion 244 and a fourth portion 245 near the buffer member 23. The fourth portion 245 is in electrical contact with the second portion 222. Along the second direction Y, the width of the fourth portion 245 is greater than the width of the third portion 244. This arrangement, with a larger width of the fourth portion 245, improves the connection strength between the fourth portion 245 and the solder ribbon 21, thereby improving the reliability of the connection between the first solar cell 201 and the solder ribbon 21. Furthermore, the smaller width of the third portion 244 results in a smaller shading area on the first solar cell 201, which is beneficial for improving the performance of the photovoltaic module. The smaller width of the third portion 244 also helps to save on the manufacturing cost of the photovoltaic module.
[0084] It should be noted that even though the solder ribbon 21 is mainly electrically connected to the first battery cell 201 through the electrical connection with the second grid line 24, the width of the solder ribbon 21 along the second direction Y is usually greater than the width of the fourth part 245 along the second direction Y. The second part 222 can still make electrical contact with the solder ribbon 21. Therefore, by setting the width of the second part 222 to be larger, the connection strength between the solder ribbon 21 and the second part 222 can still be improved, thereby improving the connection reliability between the first battery cell 201 and the solder ribbon 21.
[0085] In some embodiments, the width of the third portion 244 along the second direction Y is 0.02 mm to 0.1 mm, for example, 0.02 mm, 0.04 mm, 0.06 mm, 0.08 mm, or 0.1 mm. The smaller width of the third portion 244 within the aforementioned range results in a smaller shading area of the third portion 244 on the first solar cell 201, which is beneficial for improving the performance of the photovoltaic module. Furthermore, the smaller width of the third portion 244 also helps to reduce the manufacturing cost of the photovoltaic module.
[0086] Along the second direction Y, the width of the fourth part 245 is 0.1mm to 0.3mm, for example, 0.1mm, 0.15mm, 0.2mm, 0.25mm, or 0.3mm. The width of the fourth part 245 is within the above range. A larger width of the fourth part 245 can improve the connection strength between the fourth part 245 and the solder strip 21, preventing the fourth part 245 from detaching from the solder strip 21 under the action of the second electrical contact part 212 and the connecting part 213, thus affecting the connection reliability between the first battery cell 201 and the solder strip 21.
[0087] Figure 13 This is a cross-sectional view of the second grid line in a photovoltaic module provided in an embodiment of this disclosure.
[0088] refer to Figure 3 , Figure 4 , Figures 11 to 13In some embodiments, the surface of the fourth part 245 facing away from the first solar cell 201 is at a fourth height H4 relative to the first solar cell 201, and the surface of the third part 244 facing away from the first solar cell 201 is at a fifth height H5 relative to the first solar cell 201, with the fourth height H4 being greater than the fifth height H5. The larger fourth height H4 of the fourth part 245 ensures that even if the portion of the solder ribbon 21 near the buffer 23 is raised, the fourth part 245 can still make electrical contact with the solder ribbon 21, thereby improving the reliability of the connection between the first solar cell 201 and the solder ribbon 21. The smaller fifth height H5 of the third part 244 avoids an excessively large fifth height H5, which could affect the absorption of sunlight by the first solar cell 201. Furthermore, a smaller fifth height H5 also helps to save on the manufacturing cost of the second grid line 24.
[0089] In some embodiments, the fourth height H4 is 14μm to 18μm, for example, 14μm, 15μm, 16μm, 17μm or 18μm. The fourth height H4 is within the above range, and a larger fourth height H4 ensures that even if the portion of the solder ribbon 21 near the buffer 23 is raised, the fourth portion 245 can still make electrical contact with the solder ribbon 21, thereby improving the reliability of the connection between the first battery cell 201 and the solder ribbon 21.
[0090] The fifth height H5 is 10μm to 14μm, for example, 10μm, 11μm, 12μm, 13μm, or 14μm. A smaller fifth height H5 within this range avoids an excessively large H5, which could affect the absorption of sunlight by the first solar cell 201. Furthermore, a smaller fifth height H5 also helps to reduce the fabrication cost of the second grid line 24.
[0091] Figure 14 This is a schematic diagram of a structure of a first solar cell and a solder strip in a photovoltaic module provided in an embodiment of this disclosure. Figure 15 This is a schematic diagram of a structure of the solder strip in a photovoltaic module provided in an embodiment of this disclosure.
[0092] refer to Figure 3 , Figure 4 , Figure 14 and Figure 15 In some embodiments, the solder ribbon 21 includes a first portion 214 and a second portion 215. The first portion 214 is located on the first solar cell 201 and adjacent to the buffer 23. Along the second direction Y, the width of the first portion 214 is greater than the width of the second portion 215. The larger width of the first portion 214 increases the contact area between the second portion 222 and the first portion 214, thereby increasing the connection strength between the second portion 222 and the first portion 214, and thus improving the connection reliability between the first solar cell 201 and the solder ribbon 21. The smaller width of the second portion 215 reduces the shading area of the second portion 215 on the solar cell 20, thereby improving the performance of the photovoltaic module.
[0093] In some embodiments, the width of the first portion 214 along the second direction Y is 0.22mm to 0.3mm, for example, 0.22mm, 0.23mm, 0.24mm, 0.25mm, 0.28mm, or 0.3mm. The width of the first portion 214 is within the above range. A larger width of the first portion 214 is beneficial for increasing the contact area between the second portion 222 and the first portion 214, thereby improving the connection strength between the second portion 222 and the first portion 214, and thus improving the connection reliability between the first battery cell 201 and the solder ribbon 21.
[0094] Along the second direction Y, the width of the second portion 215 is 0.18mm to 0.22mm, for example, 0.18mm, 0.19mm, 0.2mm, 0.21mm, or 0.22mm. The width of the second portion 215 is within the above range. A smaller width of the second portion 215 reduces the shading area of the second portion 215 on the solar cell 20, thereby improving the performance of the photovoltaic module.
[0095] Figure 16 This is a partial structural schematic diagram of a photovoltaic module provided in an embodiment of the present disclosure.
[0096] refer to Figure 3 and Figure 16 In some embodiments, the photovoltaic module further includes an encapsulating film 25 and a cover plate 26. The encapsulating film 25 covers the surface of the cell string; the cover plate 26 is used to cover the surface of the encapsulating film 25 opposite to the cell string.
[0097] In some embodiments, the encapsulating film 25 includes a first encapsulating layer and a second encapsulating layer. The first encapsulating layer covers one of the first surface 203 and the second surface 204 of the battery cell 20, and the second encapsulating layer covers the other of the first surface 203 and the second surface 204 of the battery cell 20. Specifically, at least one of the first encapsulating layer and 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. Alternatively, at least one of the first encapsulating layer and the second encapsulating layer can also be an EP film, an EPE film, or a PVP film. Among them, EP film refers to a co-extruded film composed of stacked EVA film and POE film; EPE film refers to a co-extruded film formed by sequentially stacking EVA film, POE film, and EVA film; and PVP film refers to a co-extruded film formed by stacking POE film, EVA film, and POE film. Co-extruded films can be prepared by sequentially extruding one or more raw materials onto another pre-made film during the film processing, or by bonding different types of pre-made films together.
[0098] In some cases, the first encapsulation layer and the second encapsulation layer still have a boundary line before lamination. After the photovoltaic module is formed by lamination, there is no longer a concept of the first encapsulation layer and the second encapsulation layer. That is, the first encapsulation layer and the second encapsulation layer have formed an integral encapsulation film 25.
[0099] In some embodiments, the cover plate 26 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 26 facing the encapsulating film 25 can be an uneven surface or a textured surface containing multiple raised structures, thereby increasing the utilization rate of incident light. The cover plate 26 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.
[0100] 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 in that, include: Multiple battery strings, each battery string including multiple battery cells arranged along a first direction and solder strips electrically connecting adjacent battery cells, each battery cell having a first grid line extending along a second direction, the solder strips being electrically connected to the first grid line, the multiple battery cells including adjacent first battery cells and second battery cells, the second battery cells overlapping the first battery cells; A buffer element is located in the overlapping area of the first battery cell and the second battery cell, and at least a portion of the buffer element is located between the first battery cell and the solder strip. The solder strip includes a first part and a second part. The first part is located on the first battery cell and adjacent to the buffer. Along the second direction, the width of the first part is greater than the width of the second part.
2. The photovoltaic module according to claim 1, characterized in that, On the first battery cell, the first grid line near the buffer includes a first portion and a second portion that is in electrical contact with the solder strip.
3. The photovoltaic module according to claim 2, characterized in that, In the first direction, the width of the second part is greater than the width of the first grid line away from the buffer.
4. The photovoltaic module according to claim 2, characterized in that, Along the first direction, the width of the second part is greater than or equal to the width of the first part.
5. The photovoltaic module according to claim 2, characterized in that, Along the first direction, the width of the second part is 0.06mm to 0.08mm, and the width of the first grid line away from the buffer is 0.01mm to 0.05mm.
6. The photovoltaic module according to claim 2, characterized in that, The height of the second part away from the surface of the first battery cell relative to the first battery cell is a first height, and the height of the first grid line away from the surface of the first battery cell relative to the first battery cell is a second height, and the first height is greater than the second height.
7. The photovoltaic module according to claim 6, characterized in that, The height of the surface of the first part facing away from the first battery cell relative to the first battery cell is the third height, and the first height is greater than or equal to the third height.
8. The photovoltaic module according to claim 6, characterized in that, The first height is 13μm~17μm, and the second height is 8μm~12μm.
9. The photovoltaic module according to any one of claims 2 to 8, characterized in that, The battery cell also has a second grid line, the second grid line including a main body extending along the first direction and a forked structure located at both ends of the main body, the forked structure including two branches, wherein at least a portion of the second part is located between the two branches.
10. The photovoltaic module according to any one of claims 2 to 8, characterized in that, The battery cell also has a second grid line extending along a first direction. The second grid line on the first battery cell includes a third portion and a fourth portion near the buffer. The fourth portion is in electrical contact with the second portion. In the second direction, the width of the fourth portion is greater than the width of the third portion.
11. The photovoltaic module according to claim 10, characterized in that, Along the second direction, the width of the third part is 0.02mm to 0.1mm, and the width of the fourth part is 0.1mm to 0.3mm.
12. The photovoltaic module according to claim 10, characterized in that, The fourth part, whose surface faces away from the first battery cell, is at a height relative to the first battery cell of the fourth height, and the third part, whose surface faces away from the first battery cell, is at a height relative to the first battery cell of the fifth height, wherein the fourth height is greater than the fifth height.
13. The photovoltaic module according to claim 12, characterized in that, The fourth height is 14μm~18μm, and the fifth height is 10μm~14μm.
14. The photovoltaic module according to claim 1, characterized in that, The thickness of the buffer is 0.1mm to 0.3mm.