Photovoltaic module
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- CHANGSHU CANADIAN SOLAR ELECTRIC POWER TECHCO
- Filing Date
- 2025-08-04
- Publication Date
- 2026-08-07
AI Technical Summary
然而，开孔周围容易存在应力集中，在背板受力时容易从开孔的周围出现破裂
[0019]本申请实施例提供的光伏组件中，多个电池片通过焊带连接成电池串，电池串中的电池片沿光伏组件的长边方向排列(即第一方向)，可以有利于提高电池串中电池片的排列数量，提高光伏组件的集成密度。背面盖板用于保护电池片不受外界环境的影响，同时还可以提供机械支撑和电气绝缘，背面盖板上的开孔用于将电池串上的电流通过引出线引出到光伏组件外部。其中，在沿第二方向上，最邻近光伏组件的中心线的开孔的中心点与光伏组件的中心线之间的距离为N，N大于0可以使得开孔不位于光伏组件短边对应的中心线上，以避免开孔在短边中心线上时应力集中产生较大的形变造成背面盖板破裂的问题。经分析，当开孔位于光伏组件的中心点上时，开孔与两个长边之间的距离小于开孔与两个短边之间的距离，因此，在光伏组件的短边方向(即第二方向)上，开孔处于短边对应的中心线上时，应力集中的问题更为明显，形变也较大，更容易出现背面盖板破损的问题。因此，将开孔位置至少相对于短边对应的中心线处偏移，可以较大程度的解决背面盖板破损的问题，提高光伏组件的载荷性能。此外，在沿第二方向上，开孔的偏移距离根据相邻电池片之间的距离L1，以及最邻近电池片边缘的焊带与电池片边缘之间的距离L2进行计算，以控制偏移距离小于(2L2+L1)/2，可以避免引出线的长度过长导致热能损失，进而避免光伏组件的功率损失。
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Figure CN224611142U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of photovoltaic technology, and in particular to a photovoltaic module. Background Technology
[0002] The function of photovoltaic (PV) modules is to convert solar energy into electrical energy, which can then be stored in batteries or used to power loads. The structure of a PV module mainly includes a front glass panel, cell strings, and a backsheet. The cell strings absorb solar energy and convert it into electrical energy. Busbars on the cell strings collect the electrical energy and lead it to a junction box on the backsheet. The junction box then connects to external circuits or electrical equipment to supply power.
[0003] Typically, circular or elliptical openings are provided on the backplate, through which the busbars on the battery string pass to connect to the junction box on the backplate. However, stress concentration can easily occur around the openings, making the backplate prone to cracking around the openings when subjected to stress. Utility Model Content
[0004] This application provides a photovoltaic module that at least helps to improve the load performance of the photovoltaic module.
[0005] According to some embodiments of this application, one aspect of this application provides a photovoltaic module, including: a battery string, the battery string including a plurality of battery cells arranged along a first direction, and the plurality of battery strings also arranged along a second direction, the length of the photovoltaic module along the first direction being greater than the length along the second direction; a solder strip, the solder strip extending along the first direction and arranged along the second direction, the solder strip being used to connect two adjacent battery cells along the first direction; a back cover plate, the back cover plate being located on the side of the solder strip away from the back of the battery string, the back cover plate having at least one opening for passing through a lead wire; wherein, along the second direction, the distance between adjacent battery cells is L1; along the second direction, the distance between the solder strip closest to the edge of the battery cell and the edge of the battery cell is L2; along the second direction, the distance between the center point of the opening closest to the center line of the photovoltaic module and the center line of the photovoltaic module is N; L1, L2, and N satisfy the following relationship: 0 < N < (2L2 + L1) / 2.
[0006] In some embodiments, L1 ranges from 0.5 mm to 3 mm; L2 ranges from 4 mm to 15 mm.
[0007] In some embodiments, N is greater than 3 mm.
[0008] In some embodiments, the distance between the center point of the opening closest to the center line of the photovoltaic module and the center line of the photovoltaic module is greater than 0 along the first direction.
[0009] In some embodiments, the surface of the solar cell has solder joints for welding to a solder strip. The solder joints include a first solder joint and a second solder joint, which are located on the same solder strip. Along a first direction, the first solder joint is the solder joint closest to the edge of the solar cell, and the second solder joint is adjacent to the first solder joint. Along the first direction, the spacing between adjacent solar cells is L3. Along the first direction, the distance between the first solder joint and the edge of the solar cell is L4, and the distance between the second solder joint and the first solder joint is L5. Along the first direction, the distance between the center point of the opening closest to the center line of the photovoltaic module and the center line of the photovoltaic module is M. Wherein, L3, L4, L5 and M satisfy the following relationship: 0 < M < (2L5 + 2L4 + L3) / 2.
[0010] In some embodiments, L3 ranges from 0.5 mm to 15 mm; L4 ranges from 2 mm to 15 mm; and L5 ranges from 2 mm to 15 mm.
[0011] In some embodiments, the length of the solar cell along the first direction is less than the length of the solar cell along the second direction.
[0012] In some embodiments, the length of the solar cell along the first direction is V, and the length of the solar cell along the second direction is W. W and V satisfy the following relationship: 1 / 5 ≤ V / W ≤ 2 / 5.
[0013] In some embodiments, W ranges from 182 mm to 211 mm; V ranges from 45.5 mm to 108 mm.
[0014] In some embodiments, the device further includes a busbar for connecting solar cells in parallel or in series, wherein the orthographic projection of the opening does not overlap with the orthographic projection of the busbar in a direction perpendicular to the surface of the photovoltaic module.
[0015] In some embodiments, the orthographic projection of the opening is located between adjacent solar cells in a direction perpendicular to the surface of the photovoltaic module.
[0016] In some embodiments, the aperture of the opening ranges from 8 mm to 20 mm.
[0017] In some embodiments, the lead wire is connected to the diode, and the distance between the diode and the center line of the photovoltaic module along the second direction is greater than 1 / 2L1.
[0018] The technical solution provided in this application has at least the following advantages:
[0019] In the photovoltaic module provided in this application embodiment, multiple solar cells are connected into a cell string by solder ribbons. The solar cells in the cell string are arranged along the long side of the photovoltaic module (i.e., the first direction), which can help increase the number of solar cells in the cell string and improve the integration density of the photovoltaic module. The back cover plate is used to protect the solar cells from the influence of the external environment, and also provides mechanical support and electrical insulation. The openings on the back cover plate are used to lead the current on the cell string to the outside of the photovoltaic module through the lead wires. In the second direction, the distance between the center point of the opening closest to the center line of the photovoltaic module and the center line of the photovoltaic module is N. N is greater than 0, which ensures that the opening is not located on the center line corresponding to the short side of the photovoltaic module, so as to avoid stress concentration and large deformation caused by the opening on the center line of the short side, which could lead to the back cover plate cracking. Analysis revealed that when the opening is located at the center point of the photovoltaic module, the distance between the opening and the two long sides is less than the distance between the opening and the two short sides. Therefore, in the direction of the short side of the photovoltaic module (i.e., the second direction), when the opening is located on the center line corresponding to the short side, the stress concentration problem is more pronounced, the deformation is larger, and the back cover plate is more prone to damage. Therefore, offsetting the opening position at least relative to the center line corresponding to the short side can significantly alleviate the back cover plate damage problem and improve the load-bearing performance of the photovoltaic module. Furthermore, along the second direction, the offset distance of the opening is calculated based on the distance L1 between adjacent cells and the distance L2 between the solder strip of the nearest cell edge and the cell edge. Controlling the offset distance to be less than (2L2+L1) / 2 can prevent excessively long lead wires from causing heat loss and thus avoid power loss in the photovoltaic module. Attached Figure Description
[0020] 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 application or in 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 application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0021] Figure 1 A top view of a photovoltaic module provided in an embodiment of this application;
[0022] Figure 2 for Figure 1 A schematic diagram of the local method structure within the dashed box A;
[0023] Figure 3 for Figure 2 A magnified view of the structure within the dashed box B;
[0024] Figure 4 This is a top view of another photovoltaic module provided in an embodiment of this application.
[0025] Explanation of reference numerals in the attached figures:
[0026] 100. Battery string; 101. Battery cell; 110. Busbar; 111. Welding strip; 120. Back cover; 130. Opening; 112. Welding point; 1121. First welding point; 1122. Second welding point. Detailed Implementation
[0027] As is known from the background art, stress concentration is prone to occur around the opening, which can easily lead to cracking around the opening when the back plate is under stress.
[0028] Analysis revealed that when the openings on the backsheet are located in the middle area, the backsheet, especially the glass backsheet of double-glass modules, is prone to cracking at the openings, which will seriously affect the strength of the photovoltaic module.
[0029] This application provides a photovoltaic module in which the opening position is offset at least relative to the centerline corresponding to the short side, thereby significantly addressing the problem of back cover damage and improving the load-bearing performance of the photovoltaic module. Along the second direction, the offset distance of the opening is calculated based on the distance L1 between adjacent cells and the distance L2 between the solder strip of the nearest cell edge and the cell edge, to control the offset distance to be less than (2L2+L1) / 2. This avoids excessively long lead wires that could lead to heat loss, thus preventing power loss in the photovoltaic module.
[0030] In the description of the embodiments of this application, the technical terms "first", "second", etc. are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features.
[0031] In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly specified.
[0032] 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 application. 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.
[0033] In the description of the embodiments of this application, technical terms such as "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 application 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 application.
[0034] In the description of the embodiments of this application, 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. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.
[0035] In the accompanying drawings corresponding to the embodiments of this application, the thickness and area of the layers are enlarged for better understanding and ease of description. When describing a component on another component 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.
[0036] In the description of the embodiments of this application, when a component "includes" another component, other components are not excluded unless otherwise stated, and other components may be further included.
[0037] The terminology used in the description of the various embodiments herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used in the description of the various embodiments and the appended claims, the term "component" is also intended to include the plural form unless the context clearly indicates otherwise.
[0038] The embodiments of this application 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 application to facilitate a better understanding of the application. However, the technical solutions claimed in this application can be implemented even without these technical details and various variations and modifications based on the following embodiments.
[0039] Figure 1 A top view of a photovoltaic module provided in an embodiment of this application; Figure 2 for Figure 1 A schematic diagram of the local method structure within the dashed box A; Figure 3 for Figure 2 A magnified view of the structure within the dashed box B; Figure 4 This is a top view of another photovoltaic module provided in an embodiment of this application. For ease of explanation, Figures 1 to 4 The back cover plate 120 is transparent.
[0040] refer to Figures 1 to 4 One embodiment of this application provides a photovoltaic module, including: a battery string 100, a solder strip 111, and a back cover 120.
[0041] The battery string 100 includes a plurality of battery cells 101 arranged along a first direction X, and the plurality of battery strings 100 are also arranged along a second direction Y. The length of the photovoltaic module along the first direction X is greater than its length along the second direction Y, that is, the side of the photovoltaic module extending along the first direction X is the long side, and the side of the photovoltaic module extending along the second direction Y is the short side.
[0042] The solder strip 111 extends along a first direction X and is arranged along a second direction Y. The solder strip 111 is used to connect two adjacent battery cells 101 along the first direction X.
[0043] The back cover 120 is located on the side of the solder strip 111 away from the back of the battery string 100, and the back cover 120 has at least one opening 130 for passing through the lead wire (not shown).
[0044] Along the second direction Y, the distance between adjacent solar cells 101 is L1; along the second direction Y, the distance between the solder strip 111 closest to the edge of solar cell 101 and the edge of solar cell 101 is L2; along the second direction Y, the distance between the center point of the opening 130 closest to the center line S1 of the photovoltaic module and the center line S1 of the photovoltaic module is N; L1, L2 and N satisfy the following relationship: 0 < N < (2L2 + L1) / 2.
[0045] In the photovoltaic module provided in this application embodiment, multiple solar cells 101 are connected into a solar cell string 100 by solder ribbons 111. The solar cells 101 in the solar cell string 100 are arranged along the long side direction of the photovoltaic module (i.e., the first direction X), which can help increase the number of solar cells 101 in the solar cell string 100 and improve the integration density of the photovoltaic module. The back cover plate 120 is used to protect the solar cells 101 from the influence of the external environment, and also provides mechanical support and electrical insulation. The opening 130 on the back cover plate 120 is used to lead the current on the solar cell string 100 to the outside of the photovoltaic module through the lead wire. In the second direction Y, the distance between the center point of the opening 130 closest to the center line S1 of the photovoltaic module and the center line S1 of the photovoltaic module is N. N is greater than 0 so that the opening 130 is not located on the center line S1 corresponding to the short side of the photovoltaic module, so as to avoid the problem of stress concentration and large deformation caused by the opening 130 being on the center line S1 of the short side, which could lead to the cracking of the back cover plate 120. Analysis revealed that when the opening 130 is located at the center point of the photovoltaic module, the distance between the opening 130 and the two long sides is less than the distance between the opening 130 and the two short sides. Therefore, compared to when the opening 130 is located on the centerline S2 corresponding to the long side, the stress concentration problem is more pronounced and the deformation is larger when the opening 130 is located on the centerline S1 corresponding to the short side along the direction of the photovoltaic module (i.e., the second direction Y), making it more prone to damage to the back cover plate 120. Therefore, offsetting the position of the opening 130 at least relative to the centerline S1 corresponding to the short side can largely solve the problem of damage to the back cover plate 120 and improve the load performance of the photovoltaic module. Furthermore, along the second direction Y, the offset distance of the opening 130 is calculated based on the distance L1 between adjacent cells 101 and the distance L2 between the solder strip 111 closest to the edge of the cell 101 and the edge of the cell 101, to control the offset distance to be less than (2L2+L1) / 2. If the busbar is located on the center line S1 of the short side of the photovoltaic module, one end of the lead wire needs to be connected to the busbar, and the other end needs to pass through the opening 130 to the outside of the photovoltaic module. The offset distance is controlled within the above range. This can avoid the current flow path from being too long due to the lead wire or busbar length, which would lead to an increase in heat loss and thus avoid power loss of the photovoltaic module.
[0046] In some embodiments, the solar cell 101 can be any one of the following: PERC cell (Passivated Emitter and Rear Cell), PERT cell (Passivated Emitter and Rear Totally-diffused cell), TOPCon cell (Tunnel Oxide Passivated Contact), HIT / HJT cell (Heterojunction Technology), or BC cell (Back Contact). The BC cell can be an IBC cell (Interdigitated Back Contact), an HPBC cell (Hybrid Passivated Back Contact), a TBC cell combining TOPCon and IBC technologies, or an HBC cell combining HIT / HJT and IBC technologies; it can also be other types of back contact cells.
[0047] exist Figure 2 Taking a non-back-contact battery cell 101 as an example, the two ends of the solder ribbon 111 are respectively connected to the front of one battery cell 101 and the back of another battery cell 101. In other embodiments, when the battery cell is a back-contact battery, the two ends of the solder ribbon are located on the back of the two battery cells respectively.
[0048] The front side refers to the light-receiving surface, which is used to receive incident light, while the back side refers to the back side. In some embodiments, the photovoltaic module is a bifacial photovoltaic module, in which case both the front and back sides of the solar cell 101 can serve as light-receiving surfaces and can be used to receive incident light.
[0049] In some embodiments, the solar cell 101 can be a monocrystalline silicon solar cell, a polycrystalline silicon solar cell, an amorphous silicon solar cell, or a multi-component compound solar cell. Specifically, the multi-component compound solar cell can be a cadmium sulfide solar cell, a gallium arsenide solar cell, a copper indium selenide solar cell, or a perovskite solar cell.
[0050] In some embodiments, the photovoltaic module further includes an encapsulation layer (not shown) that covers the surface of the solar cell 101, with a back cover 120 located on the surface of the encapsulation layer away from the back of the solar cell 101. The encapsulation layer can be made of organic encapsulation films such as ethylene-vinyl acetate copolymer (EVA) film, polyvinyl octene coelastomer (POE) film, or polyvinyl butyral (PVB) film.
[0051] The photovoltaic module may also include a front cover plate located on the side of the encapsulation layer away from the front of the solar cell 101.
[0052] The front cover can be a glass cover, a plastic cover, or other cover with light transmission function, and the back cover can be a glass cover, a plastic cover, or other cover with light transmission function, to form a bifacial photovoltaic module. Alternatively, the back cover can also be an opaque cover.
[0053] refer to Figure 1 , Figure 2 and Figure 4 The photovoltaic module may also include a busbar 110, which is used to connect cells in series or parallel, and leads are connected to the busbar. Specifically, one end of the lead is connected to the busbar 110, and the other end is bent and extends out through the opening 130 to the outside of the back cover plate 120 of the photovoltaic module. The lead collects the electrical energy on the busbar 110 and leads it to a junction box (not shown in the figure) provided on the back cover plate 120, and then connects the junction box to an external circuit or electrical equipment to supply power to the external circuit or electrical equipment.
[0054] It should be noted that the reference Figure 1 and Figure 4 Depending on the arrangement of the cell strings 100 in the photovoltaic module, the position of the opening 130 can be adjusted according to the position of the busbar 110. The photovoltaic module includes multiple openings 130. Among them, the opening whose original position is on the center line S1 corresponding to the short side is offset relative to the center line S1 along the short side direction (i.e., the second direction Y), and the offset distance is greater than 0 and less than (2L2+L1) / 2, forming the opening 130 closest to the center line S1 of the photovoltaic module; for other openings 130 that are not originally on the center line S1 corresponding to the short side, the distance between their center point and the center line S1 of the photovoltaic module can be greater than (2L2+L1) / 2.
[0055] Along the second direction Y, the distance L1 between adjacent solar cells 101 ranges from 0.5mm to 3mm, for example, it can be 0.5mm, 0.8mm, 1mm, 1.3mm, 1.5mm, 1.7mm, 2mm, 2.2mm, 2.5mm, 2.8mm or 3mm.
[0056] Along the second direction Y, the distance L2 between the solder strip 111 closest to the edge of the battery cell 101 and the edge of the battery cell 101 ranges from 4mm to 15mm, for example, it can be 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, 12mm, 13mm, 14mm or 15mm.
[0057] In some embodiments, N is greater than 3 mm.
[0058] refer to Figure 1 and Figure 2 In some embodiments, the distance between the center point of the opening 130 closest to the center line S2 of the photovoltaic module along the first direction X and the center line S2 of the photovoltaic module is greater than 0. That is, along the long side direction of the photovoltaic module (i.e., the first direction X), the opening 130 is also offset relative to the center line S2 of the photovoltaic module in the long side direction. In this way, the problem of stress concentration when the opening 130 is located on the center line S2 corresponding to the long side can be further solved, and the problem of damage to the back cover plate 120 can be further avoided.
[0059] refer to Figures 1 to 3 In some embodiments, the surface of the battery cell 101 has solder joints 112 for welding to the solder strip 111. Solder joints 112 include a first solder joint 1121 and a second solder joint 1122. The first solder joint 1121 and the second solder joint 1122 are located on the same solder strip and along a first direction X. The first solder joint 1121 is the solder joint 112 closest to the edge of the battery cell 101, and the second solder joint 1122 is disposed adjacent to the first solder joint 1121.
[0060] Along the first direction X, the spacing between adjacent solar cells 101 is L3; along the first direction X, the distance between the first solder joint 1121 and the edge of the solar cell 101 is L4, and the distance between the second solder joint 1122 and the first solder joint 1121 is L5; along the first direction X, the distance between the center point of the opening 130 closest to the center line S2 of the photovoltaic module and the center line S2 of the photovoltaic module is M; wherein L3, L4, L5, and M satisfy the following relationship: 0 < M < (2L5 + 2L4 + L3) / 2. This avoids stress concentration when the opening 130 is located on the center line S2 corresponding to the longer side. In addition, if the busbar is located on the center line S1 of the short side of the photovoltaic module, one end of the lead wire needs to be connected to the busbar, and the other end needs to pass through the opening 130 to the outside of the photovoltaic module. The offset distance is controlled within the above range. This can also avoid the excessive offset of the opening 130 position, which would cause the lead wire length or the busbar length to be too long, resulting in an increase in the current flow path and the resulting increase in heat loss, thereby avoiding power loss of the photovoltaic module.
[0061] It should be noted that the reference Figure 1 and Figure 4 Depending on the arrangement of the cell strings 100 in the photovoltaic module, the position of the opening 130 needs to be adjusted according to the position of the busbar 110. The photovoltaic module includes multiple openings 130, see reference... Figure 3When the original opening position is offset from the opening 130 on the center line S2 corresponding to the long side, and the offset distance is greater than 0 and less than (2L5+2L4+L3) / 2, the opening 130 closest to the center line S2 of the photovoltaic module is formed; Reference Figure 4 For the opening 130 that is not originally located on the center line S2 corresponding to the long side, the distance between its center point and the center line S2 of the photovoltaic module can be greater than (2L5+2L4+L3) / 2.
[0062] Along the first direction X, the spacing L3 between adjacent solar cells 101 ranges from 0.5mm to 15mm, for example, it can be 0.5mm, 1mm, 3mm, 5mm, 7mm, 9mm, 10mm, 12mm, 14mm or 15mm.
[0063] Along the first direction X, the distance L4 between the first solder point 112 and the edge of the battery cell 101 ranges from 2mm to 15mm, for example, it can be 2mm, 3mm, 5mm, 8mm, 10mm, 11mm, 13mm, 14mm or 15mm.
[0064] Along the first direction X, the distance L5 between the second solder point 112 and the first solder point 112 ranges from 2mm to 15mm, for example, it can be 2mm, 3mm, 5mm, 8mm, 10mm, 11mm, 13mm, 14mm or 15mm.
[0065] In some embodiments, the length of the solar cell 101 along the first direction X is less than the length of the solar cell 101 along the second direction Y. Thus, the shorter side of the solar cell 101 corresponds to the longer side of the photovoltaic module, allowing for a greater number of solar cells 101 to be arranged along the longer side of the photovoltaic module, thereby improving the integration density of the photovoltaic module.
[0066] The length of the battery cell 101 along the first direction X is V, and the length of the battery cell 101 along the second direction Y is W. W and V satisfy the following relationship: 1 / 5 ≤ V / W ≤ 2 / 5.
[0067] The length W of the battery cell 101 along the second direction Y ranges from 182mm to 211mm, for example, it can be 182mm, 186mm, 190mm, 193mm, 195mm, 200mm, 205mm, 210mm or 211mm.
[0068] The length V of the battery cell 101 along the first direction X ranges from 45.5mm to 108mm, for example, it can be 45.5mm, 50mm, 56mm, 60mm, 64mm, 70mm, 75mm, 80mm, 83mm, 87mm, 90mm, 92mm, 95.5mm, 100mm, 103mm, 105mm or 108mm.
[0069] refer to Figure 4 The opening 130, which is far from the center line S1 and center line S2 of the photovoltaic module (i.e. Figure 4 The two openings 130 located below the center line S2 can be positioned between the first and second battery strings, and between the fifth and sixth battery strings, respectively. In other words, the openings 130 furthest from the photovoltaic module's center lines S1 and S2 are located on the side of the battery string closest to the edge of the photovoltaic module, away from the module's edge. Thus, the positive and negative bus lines of the photovoltaic module can be correspondingly located on the side of the battery string closest to the module's edge, away from the module's edge. When multiple photovoltaic modules are connected sequentially, the connection lines between adjacent photovoltaic modules can be shorter, thereby reducing power loss in the connection lines.
[0070] In other embodiments, the openings away from the photovoltaic module centerline S1 and centerline S2 may also be located between the second and third battery strings and between the fourth and fifth battery strings.
[0071] refer to Figure 1 and Figure 4 In some embodiments, the orthographic projection of the opening 130 does not overlap with the orthographic projection of the busbar 110 in the direction perpendicular to the surface of the photovoltaic module. Due to variations in the arrangement of the cell strings 100 within the photovoltaic module, the busbar 110 may be located on the centerline S1 corresponding to the short side of the photovoltaic module or on the centerline S2 corresponding to the long side of the photovoltaic module, potentially causing stress concentration at the opening 130 along either centerline S1 or S2. When the position of the opening 130 does not overlap with the position of the busbar 110, the position of the opening 130 does not need to be determined based on the position of the busbar 110. The offset opening 130 can avoid being located on either centerline S1 or centerline S2, thereby preventing stress concentration that could lead to cracking of the back cover 120.
[0072] In some embodiments, the orthographic projection of the opening 130 is located between adjacent solar cells 101 in a direction perpendicular to the surface of the photovoltaic module. The position of the opening 130 corresponds to the position of the junction box. The location of the opening 130 between adjacent solar cells 101 can avoid the junction box from blocking the solar cells 101. For bifacial photovoltaic modules, this is beneficial to improve the light utilization rate on the back side, thereby avoiding the problem of reduced efficiency of the photovoltaic module.
[0073] In the accompanying drawings provided in this embodiment, the circular shape of the opening 130 is used as an example, which does not constitute a limitation on the shape of the opening 130. In other embodiments, the shape of the opening can be elliptical, wherein the major axis of the ellipse is in the same direction as the first direction, and the end axis of the ellipse is in the same direction as the second direction. This allows the deformation along the minor axis to be smaller than the deformation along the major axis when the opening is elliptical. Since the stress concentration problem is more obvious and the deformation is larger in the minor axis direction, the problem of damage to the back cover plate is more likely to occur. When the opening is elliptical, the deformation along the minor axis is smaller than the deformation along the major axis, which can largely solve the problem of easy damage to the back cover plate.
[0074] In some embodiments, the aperture of the opening 130 ranges from 8mm to 20mm, specifically 8mm, 10mm, 11mm, 13mm, 15mm, 18mm, or 20mm. When the opening is elliptical, the aperture range of 8mm to 20mm for the opening 130 refers to the major axis of the opening being 8mm to 20mm.
[0075] refer to Figure 1 and Figure 2 In some embodiments, the lead wire is connected to the diode, and the diode is located as follows: Figure 1 and Figure 2 At the position indicated by the dashed circle C, the distance between the diode and the center line S1 of the photovoltaic module is greater than 1 / 2L1 along the second direction. The opening 130 is used to pass through the lead wire, which connects to the diode. The diode is usually placed in a junction box, and the area of the junction box is larger than the area of the opening 130. Therefore, the position of the opening 130 does not perfectly correspond to the position of the diode; the diode can be placed on the side of the opening 130 away from the center line S1 of the photovoltaic module.
[0076] In other embodiments, the position of the diode can also be based on Figure 1 and Figure 2 The position indicated by the dashed circle C is offset towards the center line S2, that is, it is located between two adjacent battery cells 101 in the first direction X.
[0077] In the photovoltaic module provided in this application embodiment, multiple solar cells 101 are connected into a solar cell string 100 by solder ribbons 111. The solar cells 101 in the solar cell string 100 are arranged along the long side direction of the photovoltaic module (i.e., the first direction X), which can help increase the number of solar cells 101 in the solar cell string 100 and improve the integration density of the photovoltaic module. The back cover plate 120 is used to protect the solar cells 101 from the influence of the external environment, and also provides mechanical support and electrical insulation. The opening 130 on the back cover plate 120 is used to lead the current on the solar cell string 100 to the outside of the photovoltaic module through the lead wire. In the second direction Y, the distance between the center point of the opening 130 closest to the center line S1 of the photovoltaic module and the center line S1 of the photovoltaic module is N. N is greater than 0 so that the opening 130 is not located on the center line S1 corresponding to the short side of the photovoltaic module, so as to avoid the problem of stress concentration and large deformation caused by the opening 130 being on the center line S1 of the short side, which could lead to the cracking of the back cover plate 120. Analysis revealed that when the opening 130 is located at the center point of the photovoltaic module, the distance between the opening 130 and the two long sides is less than the distance between the opening 130 and the two short sides. Therefore, along the short side direction of the photovoltaic module (i.e., the second direction Y), when the opening 130 is located on the centerline S1 corresponding to the short side, the stress concentration problem is more pronounced, the deformation is larger, and the back cover plate 120 is more prone to damage. Therefore, shifting the position of the opening 130 at least relative to the centerline S1 corresponding to the short side can significantly alleviate the problem of back cover plate 120 damage and improve the load-bearing capacity of the photovoltaic module. Furthermore, along the second direction Y, the offset distance of the opening 130 is calculated based on the distance L1 between adjacent cells 101 and the distance L2 between the solder strip 111 closest to the edge of the cell 101 and the edge of the cell 101, so as to control the offset distance to be less than (2L2+L1) / 2. This can avoid the increase in heat loss caused by the increased current flow path due to the excessive length of the lead wire or the busbar, thereby avoiding power loss of the photovoltaic module.
[0078] Those skilled in the art will understand that the above embodiments are specific examples of implementing this application, and in practical applications, various changes in form and detail can be made without departing from the spirit and scope of this application. Any person skilled in the art can make various alterations and modifications without departing from the spirit and scope of this application; therefore, the scope of protection of this application should be determined by the scope defined in the claims.
Claims
1. A photovoltaic module, characterized in that, include: A battery string, the battery string comprising a plurality of battery cells arranged along a first direction, and the plurality of battery strings further arranged along a second direction, wherein the length of the photovoltaic module along the first direction is greater than its length along the second direction; A solder strip extending along a first direction and arranged along a second direction, the solder strip being used to connect two adjacent battery cells along the first direction; A back cover plate located on the side of the solder strip away from the back of the battery string, the back cover plate having at least one opening for the lead wire to pass through; Wherein, along the second direction, the distance between adjacent solar cells is L1; along the second direction, the distance between the solder strip closest to the edge of the solar cell and the edge of the solar cell is L2; along the second direction, the distance between the center point of the opening closest to the center line of the photovoltaic module and the center line of the photovoltaic module is N; L1, L2 and N satisfy the following relationship: 0 < N < (2L2 + L1) / 2.
2. The photovoltaic module according to claim 1, characterized in that, The range of L1 is 0.5mm to 3mm; the range of L2 is 4mm to 15mm.
3. The photovoltaic module according to claim 1 or 2, characterized in that, N is greater than 3mm.
4. The photovoltaic module according to claim 1, characterized in that, Along the first direction, the distance between the center point of the opening closest to the center line of the photovoltaic module and the center line of the photovoltaic module is greater than 0.
5. The photovoltaic module according to claim 4, characterized in that, The surface of the battery cell has solder joints for welding to the solder strip. The solder joints include a first solder joint and a second solder joint. The first solder joint and the second solder joint are located on the same solder strip and along the first direction. The first solder joint is the solder joint closest to the edge of the battery cell, and the second solder joint is arranged adjacent to the first solder joint. Along the first direction, the spacing between adjacent battery cells is L3; Along the first direction, the distance between the first solder joint and the edge of the battery cell is L4, and the distance between the second solder joint and the first solder joint is L5; Along the first direction, the distance between the center point of the opening closest to the center line of the photovoltaic module and the center line of the photovoltaic module is M; Among them, L3, L4, L5 and M satisfy the following relationship: 0 < M < (2L5 + 2L4 + L3) / 2.
6. The photovoltaic module according to claim 5, characterized in that, The range of L3 is 0.5mm to 15mm; the range of L4 is 2mm to 15mm; and the range of L5 is 2mm to 15mm.
7. The photovoltaic module according to claim 1, characterized in that, The length of the battery cell along the first direction is less than the length of the battery cell along the second direction.
8. The photovoltaic module according to claim 7, characterized in that, The length of the battery cell along the first direction is V, and the length of the battery cell along the second direction is W. W and V satisfy the following relationship: 1 / 5 ≤ V / W ≤ 2 / 5.
9. The photovoltaic module according to claim 8, characterized in that, The range of W is 182mm to 211mm; the range of V is 45.5mm to 108mm.
10. The photovoltaic module according to claim 1, characterized in that, Also includes: The busbar is used to connect the solar cells in parallel or in series. In a direction perpendicular to the surface of the photovoltaic module, the orthographic projection of the opening does not overlap with the orthographic projection of the busbar.
11. The photovoltaic module according to claim 1, characterized in that, In a direction perpendicular to the surface of the photovoltaic module, the orthographic projection of the opening is located between adjacent solar cells.
12. The photovoltaic module according to claim 1, characterized in that, The diameter of the opening ranges from 8mm to 20mm.
13. The photovoltaic module according to claim 1, characterized in that, The lead wire is connected to the diode, and along the second direction, the distance between the diode and the center line of the photovoltaic module is greater than 1 / 2L1.