Photovoltaic module

Abstract

The embodiment of the present disclosure relates to the photovoltaic field, and provides a photovoltaic module, which comprises: a first cell string comprising a plurality of first cell pieces arranged along a second direction and a first welding strip connecting adjacent first cell pieces in series; a first bus bar is located at one side end of the first cell string along the second direction and is electrically connected with the first welding strips of two adjacent first cell strings; a second cell string is spaced apart from a first cell string along the second direction and faces the first cell string; a second bus bar connects the first cell string and the second cell string in parallel; a third bus bar is connected with two adjacent first cell strings and two adjacent second cell strings in series, and the third bus bar at least partially overlaps the first cell string and the second cell string; a bridge welding strip is connected with part of the third bus bar in contact; and a fourth bus bar is located at one side of the second cell string away from the first cell string and is electrically connected with the second welding strips of two adjacent second cell strings. The size of the photovoltaic module can be reduced.

Description

Technical Field

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

[0002] A solar cell is a thin film of photovoltaic semiconductors that directly generates electricity using sunlight. Also known as a "solar chip" or "photovoltaic cell," it can instantly output voltage and generate current when a circuit is established, provided it receives sufficient illumination. In physics, this is called solar photovoltaic (PV), or simply photovoltaic.

[0003] Photovoltaic modules generally refer to solar cell modules. Because the output voltage of a single solar cell is relatively low, a certain number of individual cells must be sealed together in series and parallel to form a photovoltaic module.

[0004] However, the photovoltaic modules formed by connecting them in series and parallel are currently quite large, which increases the space occupied by the entire photovoltaic module and reduces the space utilization rate of the photovoltaic module. Summary of the Invention

[0005] This disclosure provides a photovoltaic module that can at least reduce the size of the photovoltaic module.

[0006] According to some embodiments of this disclosure, one aspect of this disclosure provides a photovoltaic module, including: a plurality of first battery strings arranged along a first direction, each first battery string including a plurality of first battery cells arranged along a second direction and a first solder strip connected in series with adjacent first battery cells; a first busbar located at one end of the first battery string along the second direction and electrically connected to the first solder strips of two adjacent first battery strings; a plurality of second battery strings arranged along the first direction, each second battery string including a plurality of second battery cells arranged along the second direction and a second solder strip connected in series with adjacent second battery cells, wherein a second battery string and a first battery string are spaced apart and directly opposite each other along the second direction, and the second battery string is located on the side of the first battery string away from the first busbar; and a second busbar located at a portion of the first battery strings. Between the first battery string and the second battery string, a second busbar connects a first battery string and a second battery string directly opposite each other in parallel; a plurality of third busbars are arranged along the first direction, the third busbars being located at the ends of the first battery strings near the second battery strings, one of the third busbars being connected in series with two adjacent first battery strings and two adjacent second battery strings, the third busbars at least partially overlapping the first battery strings and the second battery strings; a plurality of bridging solder strips are arranged along the first direction, the bridging solder strips contacting and connecting a portion of the third busbars, for electrically connecting the third busbars to one first battery string and one second battery string; a fourth busbar is located on the side of the second battery string away from the first battery string, and is electrically connected to the second solder strips of two adjacent second battery strings.

[0007] In some embodiments, the first battery string includes a first front side and a first back side opposite to each other, the second battery string includes a second front side and a second back side opposite to each other, and the third busbar is located on the first back side and the second back side.

[0008] In some embodiments, the device further includes: a third solder strip, wherein one of the third solder strips is connected in parallel to one of the first battery strings and one of the second battery strings, the third solder strip being located on the first back side and the second back side and electrically connected to the third busbar; and a fourth solder strip, wherein one of the fourth solder strips is connected in parallel to one of the first battery strings and one of the second battery strings, the fourth solder strip being located on the first front side and the second front side, spaced apart from and electrically connected to the third busbar; wherein the third solder strip and the fourth solder strip are connected in parallel to different first battery strings and second battery strings, and the fourth solder strip is electrically connected to the bridging solder strip to be electrically connected to the third busbar through the bridging solder strip.

[0009] In some embodiments, the device further includes: an insulating film located on the first and second back sides of the first and second battery strings connected in parallel by the fourth solder strip, thereby spacing the third busbar from the first and second battery strings.

[0010] In some embodiments, the cross-sectional pattern of the first busbar, the third busbar, and / or the fourth busbar in a third-direction upward direction is a target pattern, the target pattern comprising: a first extension portion extending along the first direction; a second extension portion extending along the first direction, and the second extension portion being offset from the first extension portion in the first direction and in the third-direction upward direction; and a connecting portion, one end of the connecting portion being in contact with the first extension portion and the other end being in contact with the second extension portion.

[0011] In some embodiments, a portion of the first busbar overlaps with the first battery string, and a portion of the fourth busbar overlaps with the second battery string.

[0012] In some embodiments, the device further includes: a plurality of second bridging solder strips, some of which are located between the first busbar and the first solder strip to electrically connect the first battery string to the first busbar via the second bridging solder strips, and some of which are located between the fourth busbar and the second solder strips to electrically connect the second battery string to the fourth busbar via the second bridging solder strips.

[0013] In some embodiments, the first busbar overlaps with the first battery string, and the fourth busbar overlaps with the second battery string.

[0014] In some embodiments, the first battery string includes a first front side and a first back side, the second battery string includes a second front side and a second back side, the first solder strip located on the first front side is bent to the first back side and makes contact with the first busbar for electrical connection, and the second solder strip located on the second front side is bent to the second back side and makes contact with the fourth busbar for electrical connection.

[0015] In some embodiments, along the second direction, the width of the third busbar projected onto the surface of the first battery string is 1 to 7 mm, and the width of the third busbar projected onto the surface of the second battery string is 1 to 7 mm.

[0016] The technical solution provided by the embodiments of this disclosure has at least the following advantages: On the one hand, for the output of the photovoltaic module, the first battery string and the second battery string serve as the basis for providing power to the photovoltaic module. Furthermore, multiple first battery strings are connected in series through a first busbar and a third busbar, and multiple second battery strings are connected in series through a fourth busbar and a third busbar. The first battery strings and the second battery strings are connected in parallel through a second busbar and output through the second busbar. Setting the second busbar between the first battery strings and the second battery strings, that is, setting the second busbar in the middle of the photovoltaic module, can facilitate the wiring of the photovoltaic module and facilitate the output of the photovoltaic module.

[0017] On the other hand, by setting the third busbar to at least partially overlap with the first and second cell strings, the spacing between the first and second cell strings in the second direction can be reduced. This allows for an increase in the size or number of solar cells while maintaining a fixed photovoltaic module area, thereby increasing the effective utilization area of ​​the module and ultimately improving its power output. However, hiding the third busbar below the first and second cell strings presents the problem that one of the adjacent first or second cell strings is easily connected to the third busbar, while the other is not. Therefore, bridging ribbons are also provided to connect the first or second cell strings that are not easily connected to the third busbar. This improves the performance of the photovoltaic module while reducing the difficulty of its manufacturing process. Attached Figure Description

[0018] 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.

[0019] Figure 1 A top view of a photovoltaic module provided in an embodiment of this disclosure;

[0020] Figure 2 Another top view of a photovoltaic module provided in an embodiment of this disclosure;

[0021] Figure 3 Another top view of a photovoltaic module provided in an embodiment of this disclosure;

[0022] Figure 4 For along Figure 1 Cross-sectional view along the AA1 direction;

[0023] Figure 5 For along Figure 1 Cross-sectional view along the AA2 direction;

[0024] Figure 6 for Figure 3 Top view of the opposite sides of the first battery string

[0025] Figure 7 for Figure 3 Top view of the opposite side of the second battery string;

[0026] Figure 8 for Figure 2 Cross-sectional view along the BB1 ​​direction;

[0027] Figure 9 for Figure 2 Cross-sectional view along the BB2 direction;

[0028] Figure 10 for Figure 1 Cross-sectional view along the CC1 direction;

[0029] Figure 11 for Figure 1 Another cross-sectional view along the CC1 direction. Detailed Implementation

[0030] As can be seen from the background technology, the current layout of photovoltaic modules is usually such that there is a gap between the first cell string and the third busbar, and a gap between the second cell string and the third busbar. This makes the photovoltaic module longer in the second direction, and the installation space of the third busbar will take up more space in the photovoltaic module, resulting in poor space utilization of the photovoltaic module.

[0031] This disclosure provides a photovoltaic module. On one hand, for the output of the photovoltaic module, a first battery string and a second battery string serve as the basis for providing power to the photovoltaic module. Multiple first battery strings are connected in series via a first busbar and a third busbar, and multiple second battery strings are connected in series via a fourth busbar and a third busbar. The first and second battery strings are connected in parallel via a second busbar and output through the second busbar. Positioning the second busbar between the first and second battery strings, that is, placing the second busbar in the middle of the photovoltaic module, facilitates the wiring of the photovoltaic module and its output.

[0032] On the other hand, by setting the third busbar to at least partially overlap with the first and second cell strings, the spacing between the first and second cell strings in the second direction can be reduced. This allows for an increase in the size or number of solar cells while maintaining a fixed photovoltaic module area, thereby increasing the effective utilization area of ​​the module and ultimately improving its power output. However, hiding the third busbar below the first and second cell strings presents the problem that one of the adjacent first or second cell strings is easily connected to the third busbar, while the other is not. Therefore, bridging ribbons are also provided to connect the first or second cell strings that are not easily connected to the third busbar. This improves the performance of the photovoltaic module while reducing the difficulty of its manufacturing process.

[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 the embodiments of this disclosure, the term "multiple" refers to two or more (including two), similarly, "multiple groups" refers to two or more (including two groups), 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 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.

[0040] 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.

[0041] 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. Components include layers, films, regions, or plates, etc.

[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] refer to Figures 1 to 3 , Figure 1 This is a top view of a photovoltaic module provided in one embodiment of the present disclosure. Figure 2 This is another top view of a photovoltaic module provided according to an embodiment of the present disclosure. Figure 3 This is another top view of a photovoltaic module provided in an embodiment of the present disclosure, wherein, Figure 1 The first busbar of the photovoltaic module shown partially overlaps with the first cell string, and the fourth busbar partially overlaps with the second cell string. Figure 2 The first and fourth busbars of the photovoltaic module shown are spaced apart from the first and second cell strings. Figure 3 The first busbar of the photovoltaic module shown completely overlaps with the first battery string, and the fourth busbar completely overlaps with the second battery string.

[0044] In some embodiments, a photovoltaic module may include: a plurality of first cell strings 100 arranged along a first direction X, wherein the first cell strings 100 include a plurality of first cell cells 110 arranged along a second direction Y and a first solder strip 120 connecting adjacent first cell cells 110 in series.

[0045] The photovoltaic module may also include: a first busbar 101, which is located at one end of the first cell string 100 along the second direction Y and is electrically connected to the first solder strip 120 of two adjacent first cell strings 100.

[0046] The photovoltaic module may further include: a plurality of second cell strings 102 arranged along a first direction X, the second cell strings 102 including a plurality of second cell cells 112 arranged along a second direction Y and second solder strips 122 connected in series with adjacent second cell cells 112, a second cell string 102 being spaced apart from a first cell string 100 along the second direction Y and facing each other, and the second cell string 102 being located on the side of the first cell string away from the first busbar 101.

[0047] The photovoltaic module may also include: a second busbar 103, which is located between a portion of the first battery string 100 and the second battery string 102, and the second busbar 103 connects the first battery string 100 and the second battery string 102 in parallel.

[0048] The photovoltaic module may further include: a plurality of third busbars 104 arranged along a first direction X, the third busbars 104 being located at the ends of the first battery string 100 near the second battery string 102, one third busbar 104 being connected in series with two adjacent first battery strings 100 and two adjacent second battery strings 102, and the third busbar 104 at least partially overlapping with the first battery string 100 and the second battery string 102.

[0049] The photovoltaic module may further include: a plurality of bridging ribbons 105 arranged along a first direction X, wherein the bridging ribbons 105 are in contact with a portion of the third busbar 104 for electrically connecting the third busbar 104 to a first battery string 100 and a second battery string 102.

[0050] The photovoltaic module may also include: a fourth busbar 106, which is located on the side of the second cell string 102 away from the first cell string 100 and is electrically connected to the second solder strips 120 of the two adjacent second cell strings 102.

[0051] This disclosure provides a photovoltaic module. On one hand, for the output of the photovoltaic module, a first battery string 100 and a second battery string 102 serve as the basis for providing power to the photovoltaic module. Multiple first battery strings 100 are connected in series via a first busbar 101 and a third busbar 104, and multiple second battery strings 102 are connected in series via a fourth busbar 106 and a third busbar 104. The first battery strings 100 and the second battery strings 102 are connected in parallel via a second busbar 103 and output through the second busbar 103. Positioning the second busbar 103 between the first battery strings 100 and the second battery strings 102, that is, placing the second busbar 103 in the middle of the photovoltaic module, facilitates the wiring of the photovoltaic module and its output. On the other hand, by setting the third busbar 104 to overlap at least partially with the first battery string 100 and the second battery string 102, the spacing between the first battery string 100 and the second battery string 102 in the second direction Y can be reduced. Thus, with a fixed photovoltaic module area, the size or number of solar cells can be increased, the effective utilization area of ​​the module can be improved, and the module power can be increased. However, if the third busbar 104 is hidden below the first battery string 100 and the second battery string 102, there will be a problem that one of the adjacent first battery string 100 or the adjacent second battery string 102 is easy to connect to the third busbar 104, while the other is not. Therefore, a bridging ribbon 105 is also provided to connect the part of the first battery string 100 or the second battery string 102 that is not easy to connect to the third busbar 104 to the third busbar 104. This can improve the performance of the photovoltaic module while reducing the difficulty of the photovoltaic module manufacturing process.

[0052] For the first battery string 100, the first battery cell 110 in the first battery string 100 includes, but is not limited to, one or any combination of PERC (Passivated Emitter Rear Cell), IBC (Interdigitated Back Contact) cell, TOPCon (Tunnel Oxide Passivated Contact) cell, HIT / HJT (Heterojunction Technology) cell, thin-film solar cell, and tandem cell. Among them, 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 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.

[0053] It is understandable that for two adjacent first battery strings 100, the structure between the two adjacent first battery strings 100 can be considered the same, but the surface orientation is different. For example, Figure 1 As shown, the first solder strip 120 for electrically connecting two adjacent first battery strings 100 to the first busbar 101 can be located on the bottom surface of the first battery string 100, and the other can be located on the top surface of the first battery string 100. It can be considered that the two adjacent first battery strings 100 face upward and downward respectively. If the surface orientation of the first battery strings 100 is considered to be the same, for example, the two adjacent first battery strings 100 are both considered to face upward, then the two adjacent first battery strings 100 can also be considered to have different structures.

[0054] Reference Figure 1 , Figure 4 and Figure 5 ,in, Figure 4 For along Figure 1 Cross-sectional view along the AA1 direction. Figure 5 For along Figure 1 Cross-sectional view along the AA2 direction.

[0055] In some embodiments, a portion of the first busbar 101 overlaps with the first battery string 100, meaning that a portion of the first busbar 101 is hidden below the first battery string 100, or the first busbar 101 partially obscures the first battery string 100. Thus, even with a fixed photovoltaic module area, the size or number of solar cells can be increased, thereby improving the effective utilization area of ​​the module and ultimately increasing its power output.

[0056] In the second direction Y, the width of the overlapping portion of the first busbar 101 and the first battery string 100 can be 1 to 14 mm, such as 2 mm, 5 mm, 7 mm, 10 mm or 13 mm, etc. The larger the width of the overlapping portion of the first busbar 101 and the first battery string 100, the smaller the overall size of the photovoltaic module. The smaller the width of the overlapping portion of the first busbar 101 and the first battery string 100, the easier it is for the first busbar 101 to be electrically connected to the second bridging solder strip 107.

[0057] In some embodiments, the system further includes: a plurality of second bridging solder strips 107, some of which are located between the first busbar 101 and the first solder strip 120, to electrically connect the first battery string 100 to the first busbar 101 via the second bridging solder strips 107. (Refer to reference) Figure 1 , Figure 4 and Figure 5It is understandable that for two adjacent first battery strings 100, the first solder strip 120 of one is located on the bottom surface of the first battery string 100, and the first solder strip 120 of the other is located on the top surface of the first battery string 100. Taking the first bus bar 101 being hidden below the first battery string 100 as an example, the first solder strip 120 located on the bottom surface of the first battery string 100 can be electrically connected to the first bus bar 101 through direct contact connection. However, the first solder strip 120 located on the top surface of the first battery string 100 needs to be electrically connected to the first bus bar 101 through the second bridging solder strip 107, so that the two adjacent first battery strings 100 can be connected in series through the first bus bar 101.

[0058] For the first battery string 100 that needs to be electrically connected to the first busbar 101 via the second bridging solder strip 107, it is also necessary to avoid direct contact between the first busbar 101 and this part of the first battery string 100. Therefore, an insulating film 108 can be provided on the surface of this part of the first battery string 100 to isolate the first busbar 101 from the first battery string 100. The second bridging solder strip 107 then penetrates the insulating film 108 and makes contact with the first busbar 101 for electrical connection.

[0059] In some embodiments, the distance between the second bridging solder strip 107 and the first solar cell 110 can be 0.5-3mm, such as 0.7mm, 0.9mm, 1.5mm, 2.3mm, or 2.8mm, etc. It can be understood that the larger the distance between the second bridging solder strip 107 and the first solar cell 110, the greater the ability to prevent short circuits between the second bridging solder strip 107 and the first solar cell 110. The smaller the distance between the second bridging solder strip 107 and the first solar cell 110, the more solar cells can be added to the photovoltaic module with a fixed size. Therefore, setting the distance between the second bridging solder strip 107 and the first solar cell 110 to 0.5-3mm can improve the photoelectric conversion efficiency of the photovoltaic module while considering the reliability of the photovoltaic module.

[0060] In other embodiments, the structure for electrically connecting the first battery string 100 to the first busbar 101 can also be conductive adhesive or conductive tape.

[0061] refer to Figure 3 and Figure 6 ,in, Figure 6 for Figure 3 A top view of the opposite side of the first battery string.

[0062] In some embodiments, the first busbar 101 overlaps with the first battery string 100, meaning that the first busbar 101 is entirely hidden beneath the first battery string 100, or the entire first busbar 101 obscures the first battery string 100. This allows for an increase in the size or number of solar cells while maintaining a fixed photovoltaic module area, thereby increasing the effective utilization area of ​​the module and ultimately improving its power output.

[0063] The first battery string 100 includes a first front side 130 and a first back side 140. The first solder strip 120 located on the first front side 130 is bent to the first back side 140 and makes contact with the first busbar 101 for electrical connection. It can be understood that for two adjacent first battery strings 100, the first solder strip 120 of one is located on the first back side 140 of the first battery string 100, and the first solder strip 120 of the other is located on the first front side 130 of the first battery string 100. The first solder strip 120 located on the first back side 140 can be electrically connected to the first busbar 101 through direct contact connection, while the first solder strip 120 located on the first front side 130 is bent to the first back side 140 and makes contact with the first busbar 101 for electrical connection, so that the two adjacent first battery strings 100 are connected in series through the first busbar 101.

[0064] For the first battery string 100 that needs to be bent to the first back surface 140, the bent first solder ribbon 120 cannot directly contact the first back surface 140 of the first battery string 100. Moreover, the first bus bar 101 that is electrically connected to the bent first solder ribbon 120 also needs to be spaced apart from the first battery string 100 to avoid short circuit. Therefore, an insulating film 108 can also be provided on the first back surface 140 of the first battery string 100 to space the first bus bar 101 from the first battery string 100 and to space the bent first solder ribbon 120 from the first back surface 140. This improves the reliability of the photovoltaic module while achieving contact connection between the first bus bar 101 and the bent first solder ribbon 120.

[0065] For the second battery string 102, the second battery cell 112 in the second battery string 102 includes, but is not limited to, one or any combination of PERC cells (Passivated Emitter Rear Cell), IBC (Interdigitated Back Contact) cells, TOPCon (Tunnel Oxide Passivated Contact) cells, HIT / HJT (Heterojunction Technology) cells, thin-film solar cells, and tandem cells. Among them, 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 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.

[0066] The second battery string 102 is similar to the first battery string 100. The structure of two adjacent second battery strings 102 can be regarded as the same, but the surface orientation is different. Alternatively, two adjacent second battery strings 102 can be regarded as having different structures. For relevant information, please refer to the first battery string 100. It will not be repeated below.

[0067] In some embodiments, in the second direction Y, the spacing between the first solar cell 110 and the second solar cell 112 is 0.1–3 mm, for example, 0.2 mm, 0.5 mm, 1 mm, 1.5 mm, or 2.3 mm, etc. This reduces the spacing between adjacent first solar cell strings 100 and second solar cell strings 102, thereby increasing the size or number of solar cells while maintaining a fixed photovoltaic module area, improving the effective utilization area of ​​the module, and ultimately increasing the module power.

[0068] In some embodiments, the width of the first busbar 101 in the second direction Y is 4 to 16 mm, such as 5 mm, 7 mm, 10 mm, or 14 mm, etc. It can be understood that the larger the width of the first busbar 101, the greater the reliability of the connection between the first busbar 101 and the first solder strip 120; the smaller the width of the first busbar 101, the smaller the size of the photovoltaic module and the lower the cost.

[0069] In some embodiments, the thickness of the first busbar 101 can be adjusted according to the width of the first busbar 101. A larger width of the first busbar 101 allows for a smaller thickness, thereby controlling the resistance of the first busbar 101. The thickness of the first busbar 101 can be 0.1–0.3 mm, for example, 0.1 mm, 0.15 mm, 0.2 mm, or 0.27 mm, etc.

[0070] Reference Figure 1 , Figure 4 and Figure 5 In some embodiments, a portion of the fourth busbar 106 overlaps with the second battery string 102. That is, a portion of the fourth busbar 106 is hidden beneath the second battery string 102, or the fourth busbar 106 partially obscures the second battery string 102. In this way, given a fixed photovoltaic module area, the size or number of solar cells can be increased, thereby improving the effective utilization area of ​​the module and ultimately increasing its power output.

[0071] In the second direction Y, the width of the overlapping portion of the fourth busbar 106 and the second battery string 102 can be 1 to 14 mm, such as 2 mm, 5 mm, 7 mm, 10 mm or 13 mm, etc. The larger the width of the overlapping portion of the fourth busbar 106 and the second battery string 102, the smaller the overall size of the photovoltaic module. The smaller the width of the overlapping portion of the fourth busbar 106 and the second battery string 102, the easier it is for the fourth busbar 106 to be electrically connected to the second bridging solder strip 107.

[0072] In some embodiments, the system further includes: a plurality of second bridging solder strips 107, some of which are located between the fourth busbar 106 and the second solder strips 122, to electrically connect the second battery string 102 to the fourth busbar 106 via the second bridging solder strips 107. (Continue to refer to...) Figure 1 It is understandable that for two adjacent second battery strings 102, the second solder strip 122 of one is located on the bottom surface of the second battery string 102, and the second solder strip 122 of the other is located on the top surface of the second battery string 102. Taking the fourth bus bar 106 being hidden below the second battery string 102 as an example, the second solder strip 122 located on the bottom surface of the second battery string 102 can be electrically connected to the fourth bus bar 106 through direct contact connection. However, the second solder strip 122 located on the top surface of the second battery string 102 needs to be electrically connected to the fourth bus bar 106 through the second bridging solder strip 107, so that the two adjacent second battery strings 102 can be connected in series through the fourth bus bar 106.

[0073] For the second battery string 102 that needs to be electrically connected to the fourth busbar 106 via the second bridging solder strip 107, it is also necessary to avoid direct contact between the fourth busbar 106 and this part of the second battery string 102. Therefore, an insulating film 108 can be provided on the surface of this part of the second battery string 102 to isolate the fourth busbar 106 from the second battery string 102. The second bridging solder strip 107 then penetrates the insulating film 108 and makes contact with the fourth busbar 106 for electrical connection.

[0074] On the cross section perpendicular to the first direction X and the second direction Y, the cross-sectional shape of the second bridging weld strip 107 can be circular or square, that is, the second bridging weld strip 107 can be a round weld strip or a flat weld strip.

[0075] refer to Figure 3 and Figure 7 ,in, Figure 7 for Figure 3 A top view of the opposite side of the second battery string.

[0076] In some embodiments, the fourth busbar 106 overlaps with the second battery string 102, meaning that the fourth busbar 106 is entirely hidden beneath the second battery string 102, or the entire fourth busbar 106 obscures the second battery string 102. This allows for an increase in the size or number of solar cells while maintaining a fixed photovoltaic module area, thereby increasing the effective utilization area of ​​the module and ultimately improving its power output.

[0077] The second battery string 102 includes a second front side 132 and a second back side 142. The second solder strip 122 located on the second front side 132 is bent to the second back side 142 and makes contact with the fourth busbar 106 for electrical connection. It can be understood that for two adjacent second battery strings 102, the second solder strip 122 of one is located on the second back side 142 of the second battery string 102, and the second solder strip 122 of the other is located on the second front side 132 of the second battery string 102. The second solder strip 122 located on the second back side 142 can be electrically connected to the fourth busbar 106 through direct contact connection, while the second solder strip 122 located on the second front side 132 is bent to the second back side 142 and makes contact with the fourth busbar 106 for electrical connection, so that the two adjacent second battery strings 102 are connected in series by the fourth busbar 106.

[0078] For the second battery string 102 that needs to be bent to the second back side 142, the bent second solder strip 122 cannot directly contact the second back side 142 of the second battery string 102. Moreover, the fourth bus bar 106, which is electrically connected to the bent second solder strip 122, also needs to be spaced from the second battery string 102 to avoid short circuits. Therefore, an insulating film 108 can also be provided on the second back side 142 of the second battery string 102 to space the fourth bus bar 106 from the second battery string 102 and to space the bent second solder strip 122 from the second back side 142. This improves the reliability of the photovoltaic module while achieving contact connection between the fourth bus bar 106 and the bent second solder strip 122.

[0079] In some embodiments, the width of the fourth busbar 106 in the second direction Y is 4 to 16 mm, such as 5 mm, 7 mm, 10 mm, or 14 mm, etc. It is understood that the larger the width of the fourth busbar 106, the greater the reliability of the connection between the fourth busbar 106 and the second solder strip 122; the smaller the width of the fourth busbar 106, the smaller the size of the photovoltaic module and the lower the cost.

[0080] In some embodiments, the thickness of the fourth busbar 106 can be adjusted according to the width of the fourth busbar 106. A larger width of the fourth busbar 106 allows for a smaller thickness, thereby controlling the resistance of the fourth busbar 106. The thickness of the fourth busbar 106 can be 0.1–0.3 mm, for example, 0.1 mm, 0.15 mm, 0.2 mm, or 0.27 mm, etc.

[0081] In some embodiments, the first battery string 100 includes a first front side 130 and a first back side 140, and the second battery string 102 includes a second front side 132 and a second back side 142, with a first busbar 101 located on the first back side 140 and / or a fourth busbar 106 located on the second back side 142. By setting the first busbar 101 to be located on the first back side 140 and / or the fourth busbar 106 to be located on the second back side 142, the first busbar 101 can be prevented from affecting the light absorption of the first battery string 100 and / or the fourth busbar 106 can be prevented from affecting the light absorption of the second battery string 102.

[0082] In some embodiments, the first battery cell 110 and the second battery cell 112 are single-sided batteries, in which case the first front surface 130 and the second front surface 132 can serve as light-receiving surfaces to receive incident light, and the first back surface 140 and the second back surface 142 serve as backlighting surfaces. In some embodiments, the first battery cell 110 and the second battery cell 112 are double-sided batteries, in which case the first front surface 130, the second front surface 132, the first back surface 140, and the second back surface 142 can all serve as light-receiving surfaces and can all be used to receive incident light. It is understood that the backlighting surface referred to in the embodiments of this disclosure can also receive incident light, but the degree of reception of incident light is weaker than that of the light-receiving surface, and therefore it is defined as a backlighting surface.

[0083] In some embodiments, the first busbar 101 and the fourth busbar 106 may have the same structure, thereby reducing the specifications of photovoltaic module materials and lowering the manufacturing process difficulty of photovoltaic modules.

[0084] For the second busbar 103, the photovoltaic module can have two second busbars 103, one of which serves as the total positive output and the other as the total negative output. The two second busbars 103 can be located on opposite sides of the photovoltaic module along the first direction X. On the one hand, they connect the first battery string 100 and the second battery string 102 in parallel, and on the other hand, they serve as the total positive and total negative outputs.

[0085] Reference Figure 2 , Figure 8 and Figure 9 ,in, Figure 8 for Figure 2 Cross-sectional view along the BB1 ​​direction. Figure 9 for Figure 2 Cross-sectional view along the BB2 direction.

[0086] In some embodiments, the third busbar 104 is located on the first back side 140 and the second back side 142. In this way, with a fixed photovoltaic module area, the size or number of solar cells can be increased, the effective utilization area of ​​the module can be increased, and the power of the photovoltaic module can be increased. At the same time, the third busbar 104 is prevented from blocking the light absorption of the first cell string 100 and the second cell string 102, thereby improving the photoelectric conversion efficiency of the photovoltaic module.

[0087] In some embodiments, the photovoltaic module may further include: a third solder ribbon 109, wherein a third solder ribbon 109 is connected in parallel to a first battery string 100 and a second battery string 102, the third solder ribbon 109 is located on a first back side 140 and a second back side 142, and is electrically connected to a third busbar 104; and a fourth solder ribbon 200, wherein a fourth solder ribbon 200 is connected in parallel to a first battery string 100 and a second battery string 102, the fourth solder ribbon 200 is located on a first front side 130 and a second front side 132, and is spaced apart from and electrically connected to the third busbar 104; wherein the third solder ribbon 109 and the fourth solder ribbon 200 are connected in parallel to different first battery strings 100 and second battery strings 102, and the fourth solder ribbon 200 is electrically connected to a bridging solder ribbon 105 to be electrically connected to the third busbar 104 through the bridging solder ribbon 105.

[0088] For the first battery string 100 and the second battery string 102 that need to be connected in parallel, a third solder strip 109 located on the first back side 140 and the second back side 142 and a fourth solder strip 200 located on the first front side 130 and the second front side 132 are needed to connect the first battery string 100 and the second battery string 102 in parallel. Moreover, for the third bus bar 104, taking the third bus bar 104 located on the back side as an example, the third solder strip 109 located on the first back side 140 and the second back side 142 can be directly contacted and electrically connected to the third bus bar 104. The fourth solder strip 200 located on the first front side 130 and the second front side 132 is spaced apart from the third bus bar 104 and needs to be electrically connected to the third bus bar 104 through a bridging solder strip 105. By setting the bridging solder strip 105, the fourth solder strip 200 can be electrically connected to the third bus bar 104.

[0089] In some embodiments, the photovoltaic module may further include: an insulating film 108, which is located on the first back side 140 and the second back side 142 of the first battery string 100 and the second battery string 102 connected in parallel by the fourth solder strip, and spaced the third busbar 104 from the first battery string 100 and the second battery string 102.

[0090] For the third busbar 104, the third busbar 104 needs to be spaced apart from the first battery string 100 and the second battery string 102 connected in parallel by the fourth solder strip, so as to avoid short circuits between adjacent first battery strings 100 and adjacent second battery strings 102. Therefore, an insulating film 108 can also be provided to separate the third busbar 104 from the first battery string 100 and the second battery string 102, thereby improving the reliability of the photovoltaic module.

[0091] In some embodiments, the insulating film 108 may be a two-layer structure, with one layer covering the first back surface 140 and the other layer covering the second back surface 142, thereby reserving space for the bridging solder strip 105 to extend in the middle portion, thereby facilitating the contact between the bridging solder strip 105 and the third busbar 104; in other embodiments, holes may be cut in the portion of the insulating film 108 corresponding to the bridging solder strip 105, so that the bridging solder strip 105 can pass through these holes and make contact with the third busbar 104 for electrical connection.

[0092] For the bridging solder strip 105, the bridging solder strip 105 penetrates the insulating film 108 and makes contact with the third busbar 104.

[0093] In some embodiments, the width of the third busbar 104 in the second direction Y is 4 to 16 mm, such as 5 mm, 7 mm, 10 mm, or 14 mm, etc. It is understood that the larger the width of the third busbar 104, the greater the reliability of the connection between the third busbar 104 and the third and fourth solder strips; the smaller the width of the third busbar 104, the smaller the size of the photovoltaic module and the lower the cost.

[0094] Along the second direction Y, the width of the third busbar 104 projected onto the surface of the first battery string 100 is 1–7 mm, for example, 2 mm, 3 mm, 4 mm, 5 mm, or 6 mm, etc. The width of the third busbar 104 projected onto the surface of the second battery string 102 is also 1–7 mm, for example, 2 mm, 3 mm, 4 mm, 5 mm, or 6 mm, etc. In other words, the overlap width between the third busbar 104 and the first battery string 100 is 1–7 mm, and the overlap width between the third busbar 104 and the second battery string 102 is 1–7 mm. The larger the overlap width between the third busbar 104 and the first and second battery strings 100, the smaller the overall size of the photovoltaic module. Conversely, the smaller the overlap width between the third busbar 104 and the first and second battery strings 100, the easier it is for the third busbar 104 to be electrically connected to the bridging solder strip 105.

[0095] In some embodiments, the thickness of the third busbar 104 can be adjusted according to the width of the third busbar 104. A larger width of the third busbar 104 allows for a smaller thickness, thereby controlling the resistance of the third busbar 104. The thickness of the third busbar 104 can be 0.1–0.3 mm, for example, 0.1 mm, 0.15 mm, 0.2 mm, or 0.27 mm, etc.

[0096] In some embodiments, the width of the first busbar 101 may be smaller than the width of the third busbar 104. It is understood that the first busbar 101 is only electrically connected to the first battery string 100, while the third busbar 104 needs to be electrically connected to both the first battery string 100 and the second battery string 102. Therefore, setting the width of the first busbar 101 to be shorter can reduce costs and decrease the size of the photovoltaic module. Similarly, the width of the fourth busbar 106 may also be smaller than that of the third busbar 104.

[0097] Reference Figure 1 and Figure 10 ,in, Figure 10 for Figure 1 Cross-sectional view along the CC1 direction.

[0098] In some embodiments, the cross-sectional pattern of the first busbar 101, the third busbar 104, and / or the fourth busbar 106 in the third-direction upward direction is a target pattern. The target pattern includes: a first extension 116 extending along a first direction X; a second extension 126 extending along the first direction X, and the second extension 126 being offset from the first extension 116 in both the first direction X and the third-direction upward direction; and a connecting portion 136, one end of which is in contact with the first extension 116, and the other end of which is in contact with the second extension 126. In other words, the cross-sectional pattern of the first busbar 101, the third busbar 104, and / or the fourth busbar 106 in the third-direction upward direction resembles a lightning bolt. Thus, the first busbar 101, the third busbar 104, and / or the fourth busbar 106 can reserve space between themselves and a portion of the first battery string 100 and the second battery string 102, thereby facilitating the assembly of the entire photovoltaic module.

[0099] It is understood that in some embodiments, an insulating film 108 is also included, which is located on the surface of a portion of the first battery string 100 and a portion of the second battery string 102. The first busbar 101, the third busbar 104 and / or the fourth busbar 106 are arranged in a lightning-like cross-sectional pattern in a third direction, and space can also be reserved for the insulating film 108.

[0100] Reference Figure 1 and Figure 11 , Figure 11 Another approach provided for an embodiment of this disclosure Figure 1 Cross-sectional view along the CC1 direction.

[0101] In some embodiments, the thickness of the first extension 116 may be greater than the thickness of the second extension 126, thereby reducing the height difference between the bottom surface of the first extension 116 and the bottom surface of the second extension 126, which facilitates the subsequent installation of the encapsulating film and the cover plate.

[0102] The thickness difference between the thickness of the first extension 116 and the thickness of the second extension 126 can be equal to the thickness of the insulating film 108, thereby controlling the bottom surface of the first extension 116 and the bottom surface of the second extension 126 to be relatively flat.

[0103] This disclosure provides a photovoltaic module. On one hand, for the output of the photovoltaic module, a first battery string 100 and a second battery string 102 serve as the basis for providing power to the photovoltaic module. Multiple first battery strings 100 are connected in series via a first busbar 101 and a third busbar 104, and multiple second battery strings 102 are connected in series via a fourth busbar 106 and a third busbar 104. The first battery strings 100 and the second battery strings 102 are connected in parallel via a second busbar 103 and output through the second busbar 103. Positioning the second busbar 103 between the first battery strings 100 and the second battery strings 102, that is, placing the second busbar 103 in the middle of the photovoltaic module, facilitates the wiring of the photovoltaic module and its output. On the other hand, by setting the third busbar 104 to overlap at least partially with the first battery string 100 and the second battery string 102, the spacing between the first battery string 100 and the second battery string 102 in the second direction Y can be reduced. Thus, with a fixed photovoltaic module area, the size or number of solar cells can be increased, the effective utilization area of ​​the module can be improved, and the module power can be increased. However, if the third busbar 104 is hidden below the first battery string 100 and the second battery string 102, there will be a problem that one of the adjacent first battery string 100 or the adjacent second battery string 102 is easy to connect to the third busbar 104, while the other is not. Therefore, a bridging ribbon 105 is also provided to connect the part of the first battery string 100 or the second battery string 102 that is not easy to connect to the third busbar 104 to the third busbar 104. This can improve the performance of the photovoltaic module while reducing the difficulty of the photovoltaic module manufacturing process.

[0104] 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 the embodiments of this disclosure. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the embodiments of this disclosure; therefore, the scope of protection of the embodiments of this disclosure should be determined by the scope defined in the claims.

Claims

1. A photovoltaic module, characterized by, The application comprises: a plurality of first battery strings arranged along a first direction, each first battery string comprising a plurality of first battery pieces arranged along a second direction and first welding bands connecting adjacent first battery pieces in series; a first busbar located at one end of the first battery string along the second direction and electrically connected to the first welding bands of two adjacent first battery strings; a plurality of second battery strings arranged along the first direction, each second battery string comprising a plurality of second battery pieces arranged along the second direction and second welding bands connecting adjacent second battery pieces in series, one second battery string being spaced apart from and facing one first battery string along the second direction, and the second battery string being located at one side of the first battery string away from the first busbar; a second busbar located between part of the first battery string and the second battery string, one second busbar connecting one first battery string and one second battery string in parallel; a plurality of third busbars arranged along the first direction, each third busbar being located at the end of the first battery string close to the second battery string, each third busbar being connected in series to two adjacent first battery strings and two adjacent second battery strings, and each third busbar at least partially overlapping the first battery string and the second battery string; a plurality of bridge welding bands arranged along the first direction, each bridge welding band being in contact with part of the third busbar and electrically connecting the third busbar with one first battery string and one second battery string; a fourth busbar located at one side of the second battery string away from the first battery string and electrically connected to the second welding bands of two adjacent second battery strings; the first battery string comprises opposite first front and back surfaces, the second battery string comprises opposite second front and back surfaces, and the third busbar is located at the first back surface and the second back surface; a fourth welding band connecting one first battery string and one second battery string in parallel, the fourth welding band being located at the first front surface and the second front surface, spaced apart from and electrically connected to the third busbar, and electrically connected to the bridge welding band to be electrically connected to the third busbar through the bridge welding band.

2. The photovoltaic module of claim 1, wherein, Further comprising: a third welding band connecting one first battery string and one second battery string in parallel, the third welding band being located at the first back surface and the second back surface and in contact with the third busbar; wherein the third welding band and the fourth welding band connect different first battery strings and second battery strings in parallel.

3. The photovoltaic module of claim 2, wherein, Further comprising: an insulating adhesive film located at the first back surface and the second back surface of the first battery string and the second battery string connected in parallel by the fourth welding band, spacing apart the third busbar from the first battery string and the second battery string.

4. The photovoltaic module of claim 1, wherein, The first busbar, the third busbar and / or the fourth busbar have a target pattern in a cross-sectional pattern in a third direction, the target pattern comprising: a first extension extending along the first direction; A second extension part extending in the first direction and staggered with the first extension part in the first and third directions; A connecting part having one end in contact with the first extension part and the other end in contact with the second extension part.

5. The photovoltaic module of claim 1, wherein, Part of the first bus bar overlaps with the first battery string, and part of the fourth bus bar overlaps with the second battery string.

6. The photovoltaic module of claim 5, wherein, Further comprising: A plurality of second bridge welding strips, part of which are located between the first bus bar and the first welding strip to electrically connect the first battery string and the first bus bar through the second bridge welding strip, and part of which are located between the fourth bus bar and the second welding strip to electrically connect the second battery string and the fourth bus bar through the second bridge welding strip.

7. The photovoltaic module of claim 1, wherein, The first bus bar overlaps with the first battery string, and the fourth bus bar overlaps with the second battery string.

8. The photovoltaic module of claim 7, wherein, The first battery string includes opposite first front and back surfaces, and the second battery string includes opposite second front and back surfaces, the first welding strip located on the first front surface is bent to the first back surface to be in contact and electrically connected with the first bus bar, and the second welding strip located on the second front surface is bent to the second back surface to be electrically connected with the fourth bus bar.

9. The photovoltaic module of claim 1, wherein, In the second direction, the width of the third bus bar in the surface orthographic projection of the first battery string is 1-7 mm, and the width of the third bus bar in the surface orthographic projection of the second battery string is 1-7 mm.

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