Photovoltaic module

Abstract

The embodiment of the invention relates to the photovoltaic field, and provides a photovoltaic module, which comprises a first battery string and a second battery string, and is characterized in that the first battery string comprises a plurality of first battery pieces arranged along a second direction and first welding strips connected in series with the adjacent first battery pieces; the first bus bars are positioned at the end parts of one sides of the first battery strings along the second direction and are electrically connected with the first welding strips of the two adjacent first battery strings; a second battery string and a first battery string are spaced along a second direction and directly face each other; a second bus bar connects a first battery string and a second battery string which are opposite to each other in parallel; a third bus bar is connected in series with the two adjacent first battery strings and the two adjacent second battery strings, and at least part of the third bus bar is overlapped with the first battery strings and the second battery strings; the bridging welding strip is in contact connection with part of the third bus bars; and the fourth bus bar is positioned on one side, far away from the first battery string, of the second battery string, and is electrically connected with the second welding strips of the two adjacent second battery strings. The size of the photovoltaic module can be reduced.

Description

Technical Field

[0001] The embodiments of the present disclosure relate to the photovoltaic field, and in particular to a photovoltaic module. Background Art

[0002] Solar cells are a type of photoelectric semiconductor sheet that uses sunlight to generate electricity directly. They are also called "solar chips" or "photovoltaics". As long as they are illuminated under certain conditions, they can instantly output voltage and generate current in a circuit. In physics, this is called solar photovoltaic (PV), or photovoltaic for short.

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

[0004] However, the size of the photovoltaic modules currently formed by series-parallel connection is relatively large, resulting in a larger occupied space for the entire photovoltaic module, which will reduce the space utilization rate of the photovoltaic module. Summary of the invention

[0005] The embodiments of the present disclosure provide a photovoltaic module, which can at least reduce the size of the photovoltaic module.

[0006] According to some embodiments of the present disclosure, on the one hand, the embodiments of the present disclosure provide a photovoltaic module, including: a plurality of first battery strings arranged along a first direction, the first battery string including a plurality of first battery cells arranged along a second direction and a first welding strip connecting adjacent first battery cells in series; a first bus bar, the first bus bar is located at one end of the first battery string along the second direction, and is electrically connected to the first welding strips of two adjacent first battery strings; a plurality of second battery strings arranged along the first direction, the second battery strings including a plurality of second battery cells arranged along the second direction and a second welding strip connecting adjacent second battery cells in series, a second battery string is spaced apart and opposite to a first battery string along the second direction, and the second battery string is located on a side of the first battery string away from the first bus bar; a second bus bar, the second bus bar is located at a portion of the first battery string Between the battery string and the second battery string, a second bus bar connects the first battery string and the second battery string facing each other in parallel; a plurality of third bus bars arranged along the first direction, the third bus bar is located at the end of the first battery string close to the second battery string, a third bus bar is connected in series with two adjacent first battery strings and two adjacent second battery strings, and the third bus bar at least partially overlaps with the first battery string and the second battery string; a plurality of bridging welding strips arranged along the first direction, the bridging welding strips are in contact with and connected to part of the third bus bars, and are used to electrically connect the third bus bar with one of the first battery strings and one of the second battery strings; a fourth bus bar, the fourth bus bar is located on the side of the second battery string away from the first battery string, and is electrically connected to the second welding 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 bus bar is located at the first back side and the second back side.

[0008] In some embodiments, it also includes: a third welding strip, the third welding strip is connected with the first battery string and the second battery string in parallel, the third welding strip is located at the first back side and the second back side, and is in contact with and electrically connected to the third bus bar; a fourth welding strip, the fourth welding strip is connected with the first battery string and the second battery string in parallel, the fourth welding strip is located at the first front side and the second front side, and is spaced from and electrically connected to the third bus bar; wherein the third welding strip and the fourth welding strip are connected with different first battery strings and second battery strings in parallel, and the fourth welding strip is electrically connected to the bridging welding strip, so as to be electrically connected to the third bus bar through the bridging welding strip.

[0009] In some embodiments, it also includes: an insulating adhesive film, which is located on the first back side and the second back side of the first battery string and the second battery string connected in parallel by the fourth welding strip, separating the third bus bar from the first battery string and the second battery string.

[0010] In some embodiments, the cross-sectional pattern of the first bus bar, the third bus bar and / or the fourth bus bar in the third direction is a target pattern, and the target pattern includes: a first extension portion, the first extension portion extends along the first direction; a second extension portion, the second extension portion extends along the first direction, and the second extension portion is staggered with the first extension portion in the first direction and the third direction; a connecting portion, one end of the connecting portion is in contact and connected with the first extension portion, and the other end is in contact and connected with the second extension portion.

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

[0012] In some embodiments, it also includes: a plurality of second bridging welding strips, some of which are located between the first bus bar and the first welding strip, so as to electrically connect the first battery string with the first bus bar through the second bridging welding strip, and some of which are located between the fourth bus bar and the second welding strip, so as to electrically connect the second battery string with the fourth bus bar through the second bridging welding strip.

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

[0014] In some embodiments, the first battery string includes a first front side and a first back side relative to each other, the second battery string includes a second front side and a second back side relative to each other, the first welding strip located on the first front side is bent to the first back side to contact and electrically connect with the first bus bar, and the second welding strip located on the second front side is bent to the second back side to electrically connect with the fourth bus bar.

[0015] In some embodiments, along the second direction, the width of the third bus bar projected on the surface of the first battery string is 1-7 mm, and the width of the third bus bar projected on the surface of the second battery string is 1-7 mm.

[0016] The technical solution provided by the embodiments of the present 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, and a plurality of first battery strings are connected in series through a first bus bar and a third bus bar, a plurality of second battery strings are connected in series through a fourth bus bar and a third bus bar, and the first battery string and the second battery string are connected in parallel through the second bus bar, and output through the second bus bar, and the second bus bar is set between the first battery string and the second battery string, that is, the second bus bar is set in the middle of the photovoltaic module, which can facilitate the wiring of the photovoltaic module and the output of the photovoltaic module.

[0017] On the other hand, setting the third bus bar to at least partially overlap the first cell string and the second cell string can reduce the spacing between the first cell string and the second cell string in the second direction, so that when the area of ​​the photovoltaic module is constant, 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 module can be increased. Hiding the third bus bar under the first cell string and the second cell string will cause the problem that one of the adjacent first cell string or the adjacent second cell string is convenient to be electrically connected to the third bus bar, while the other is not convenient to be electrically connected to the third bus bar. Therefore, a bridging welding strip is also provided, and the part of the first cell string or the second cell string that is not convenient to be electrically connected to the third bus bar is connected to the third bus bar by the bridging welding strip, so as to improve the performance of the photovoltaic module while reducing the difficulty of the photovoltaic module manufacturing process. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] One or more embodiments are exemplarily illustrated by pictures in the corresponding drawings, and these exemplified descriptions do not constitute a limitation on the embodiments. Unless otherwise specified, the pictures in the drawings do not constitute a scale limitation. In order to more clearly illustrate the embodiments of the present disclosure or the technical solutions in the traditional technology, the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 A top view of a photovoltaic assembly provided by an embodiment of the present disclosure;

[0020] Figure 2 Another top view of a photovoltaic module provided by an embodiment of the present disclosure;

[0021] Figure 3 Another top view of a photovoltaic module provided by an embodiment of the present disclosure;

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

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

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

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

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

[0027] Fig. 9 for Figure 2 Cross-section along the BB2 direction;

[0028] Fig.10 for Figure 1 The cross-section along CC1 direction;

[0029] Fig.11 for Figure 1 Another cross-sectional view along CC1 direction. DETAILED DESCRIPTION

[0030] From the background technology, it can be known that the current layout of photovoltaic modules is usually that the first battery string is spaced from the third bus bar, and the second battery string is spaced from the third bus bar. This will make the size of the photovoltaic module longer in the second direction, and the installation space of the third bus bar will increase the space occupied by the photovoltaic module, resulting in poor space utilization of the photovoltaic module.

[0031] The disclosed embodiment provides a photovoltaic module. 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 for the photovoltaic module, and a plurality of first battery strings are connected in series through a first bus bar and a third bus bar, a plurality of second battery strings are connected in series through a fourth bus bar and a third bus bar, and the first battery string and the second battery string are connected in parallel through the second bus bar, and output is performed through the second bus bar. The second bus bar is arranged between the first battery string and the second battery string, that is, the second bus bar is arranged in the middle of the photovoltaic module, which can facilitate the wiring of the photovoltaic module and the output of the photovoltaic module.

[0032] On the other hand, setting the third bus bar to at least partially overlap the first cell string and the second cell string can reduce the spacing between the first cell string and the second cell string in the second direction, so that when the area of ​​the photovoltaic module is constant, 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 module can be increased. Hiding the third bus bar under the first cell string and the second cell string will cause the problem that one of the adjacent first cell string or the adjacent second cell string is convenient to be electrically connected to the third bus bar, while the other is not convenient to be electrically connected to the third bus bar. Therefore, a bridging welding strip is also provided, and the part of the first cell string or the second cell string that is not convenient to be electrically connected to the third bus bar is connected to the third bus bar by the bridging welding strip, so as to improve the performance of the photovoltaic module while reducing the difficulty of the photovoltaic module manufacturing process.

[0033] In the description of the embodiments of the present disclosure, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present disclosure, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0034] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present disclosure. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0035] In the description of the embodiments of the present disclosure, the term "and / or" is only a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists, A and B exist at the same time, and B exists. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0036] In the description of the embodiments of the present disclosure, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0037] In the description of the embodiments of the present disclosure, the orientations or positional relationships indicated by technical terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", and "circumferential" are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of describing the embodiments of the present disclosure and simplifying the description. They do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the embodiments of the present disclosure.

[0038] In the description of the embodiments of the present disclosure, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present disclosure can be understood according to the specific circumstances.

[0039] In the accompanying drawings corresponding to the embodiments of the present disclosure, the thickness and area of ​​the layers are magnified for better understanding and ease of description. When describing a component (such as a layer, a film, a region or a substrate) on another component or on the surface of another component, the component may be "directly" located on the surface of the other component, or a third component may be present between the two components. On the contrary, when describing a component on the surface of another component or when another component is formed or provided on the surface of a component, it means that there is no third component between the two components. In addition, when describing a component as being "substantially" 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 partial edge of the entire surface.

[0040] In the description of the embodiments of the present disclosure, when a component "includes" another component, unless otherwise specified, other components are not excluded, and other components may be further included. In addition, when a component such as a layer, a film, a region, or a plate is referred to as being "on / located on" another component, it may 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 exist in between. In addition, when a component such as a layer, a film, a region, a plate, etc. is "directly located on" another component, or when a component such as a layer, a film, a region, a plate, etc. is located on the surface of another component, it means that no other components are located in between.

[0041] The terms used in the description of the various embodiments described herein are only used to describe specific embodiments and are not intended to be limiting. As used in the description of the various embodiments described and in the appended claims, "the components" are also intended to include plural forms unless the context clearly indicates otherwise. Among them, components include components such as layers, films, regions, or plates.

[0042] The following will describe the various embodiments of the present disclosure in detail with reference to the accompanying drawings. However, it will be appreciated by those skilled in the art that in the various embodiments of the present disclosure, many technical details are provided in order to enable the reader to better understand the present disclosure. However, even without these technical details and various changes and modifications based on the following embodiments, the technical solutions claimed in the present disclosure can be implemented.

[0043] refer to Figures 1 to 3 , Figure 1 A top view of a photovoltaic assembly provided by an embodiment of the present disclosure, Figure 2 Another top view of a photovoltaic module provided by an embodiment of the present disclosure, Figure 3 Another top view of a photovoltaic assembly provided by an embodiment of the present disclosure, wherein: Figure 1 The first bus bar of the photovoltaic assembly shown overlaps partially with the first battery string, and the fourth bus bar overlaps partially with the second battery string. Figure 2 The first bus bar and the fourth bus bar of the photovoltaic assembly shown are spaced apart from the first battery string and the second battery string. Figure 3 The first bus bar of the photovoltaic assembly shown completely overlaps with the first battery string, and the fourth bus bar completely overlaps with the second battery string.

[0044] In some embodiments, a photovoltaic module may include: a plurality of first battery strings 100 arranged along a first direction X, the first battery string 100 including a plurality of first battery cells 110 arranged along a second direction Y and a first welding ribbon 120 connecting adjacent first battery cells 110 in series.

[0045] The photovoltaic module may further include: a first bus bar 101 , which is located at one end of the first battery string 100 along the second direction Y and is electrically connected to the first welding strips 120 of two adjacent first battery strings 100 .

[0046] The photovoltaic module may also include: a plurality of second battery strings 102 arranged along a first direction X, the second battery string 102 including a plurality of second battery cells 112 arranged along a second direction Y and a second welding strip 122 connecting adjacent second battery cells 112 in series, a second battery string 102 being spaced apart and facing a first battery string 100 along the second direction Y, and the second battery string 102 being located on a side of the first battery string away from the first bus bar 101.

[0047] The photovoltaic assembly may further include: a second bus bar 103 , the second bus bar 103 is located between a portion of the first battery string 100 and the second battery string 102 , and a second bus bar 103 connects a first battery string 100 and a second battery string 102 facing each other in parallel.

[0048] The photovoltaic module may also include: a plurality of third bus bars 104 arranged along the first direction X, the third bus bar 104 being located at the end of the first battery string 100 close to the second battery string 102, a third bus bar 104 being connected in series with two adjacent first battery strings 100 and two adjacent second battery strings 102, and the third bus bar 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 the first direction X, the bridging ribbons 105 contacting and connecting with a portion of the third bus bar 104 , for electrically connecting the third bus bar 104 with a first battery string 100 and a second battery string 102 .

[0050] The photovoltaic assembly may further include: a fourth bus bar 106 , which is located at a side of the second battery string 102 away from the first battery string 100 and is electrically connected to the second welding strips 120 of two adjacent second battery strings 102 .

[0051] The disclosed embodiment provides a photovoltaic module. On the one hand, for the output of the photovoltaic module, the first battery string 100 and the second battery string 102 serve as the basis for providing power to the photovoltaic module, and multiple first battery strings 100 are connected in series through the first bus bar 101 and the third bus bar 104, and multiple second battery strings 102 are connected in series through the fourth bus bar 106 and the third bus bar 104, and the first battery string 100 and the second battery string 102 are connected in parallel through the second bus bar 103, and output is performed through the second bus bar 103. The second bus bar 103 is set between the first battery string 100 and the second battery string 102, that is, the second bus bar 103 is set in the middle of the photovoltaic module, which can facilitate the wiring of the photovoltaic module and the output of the photovoltaic module. On the other hand, by setting the third bus bar 104 to at least partially overlap the first cell string 100 and the second cell string 102, the spacing between the first cell string 100 and the second cell string 102 in the second direction Y can be reduced, so that when the area of ​​the photovoltaic module is constant, 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 module can be increased. Hiding the third bus bar 104 under the first cell string 100 and the second cell string 102 will cause the problem that one of the adjacent first cell string 100 or the adjacent second cell string 102 is convenient to be electrically connected to the third bus bar 104, while the other is not convenient to be electrically connected to the third bus bar 104. Therefore, a bridging welding strip 105 is also provided, and the part of the first cell string 100 or the second cell string 102 that is not convenient to be electrically connected to the third bus bar 104 is connected to the third bus bar 104 through the bridging welding strip 105, so as to 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 battery (Passivated Emitter Rear Cell), IBC (Interdigitated Back Contact), TOPCon (Tunnel Oxide Passivated Contact), HIT / HJT (Heterojunction Technology) battery, solar thin film battery, and stacked battery. Among them, solar thin film battery includes, but is not limited to, perovskite solar thin film battery, copper indium selenide solar thin film battery, gallium arsenide solar thin film battery, and cadmium sulfide solar thin film battery. Stacked battery includes, but is not limited to, perovskite battery superimposed on crystalline silicon battery, perovskite battery superimposed on perovskite battery, and perovskite battery superimposed on thin film battery.

[0053] It is understandable that, for two adjacent first battery strings 100, the structures of the two adjacent first battery strings 100 can be considered to be the same, but the surface orientations are different. For example, Figure 1 As shown, one first welding strip 120 of two adjacent first battery strings 100 for electrically connecting to the first bus bar 101 may be located on the bottom surface of the first battery string 100, and the other may be located on the top surface of the first battery string 100. It can be regarded that one of the two adjacent first battery strings 100 faces upward and the other faces downward. If the surface orientations of the first battery strings 100 are regarded as the same, for example, the two adjacent first battery strings 100 are regarded as both facing upward, then the two adjacent first battery strings 100 can also be regarded as having different structures.

[0054] Combined with reference Figure 1 , Figure 4 and Figure 5 ,in, Figure 4 For along Figure 1 The cross-section view along the AA1 direction, Figure 5 For along Figure 1 Cross-sectional view along the AA2 direction.

[0055] In some embodiments, part of the first bus bar 101 overlaps with the first battery string 100, that is, part of the first bus bar 101 is hidden under the first battery string 100, or the first bus bar 101 covers part of the first battery string 100. In this way, the size or number of solar cells can be increased when the area of ​​the photovoltaic module is constant, and the effective utilization area of ​​the module can be increased, thereby increasing the power of the module.

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

[0057] In some embodiments, the present invention further comprises: a plurality of second bridging ribbons 107, wherein some of the second bridging ribbons 107 are located between the first bus bar 101 and the first ribbon 120, so as to electrically connect the first battery string 100 to the first bus bar 101 through the second bridging ribbons 107. Figure 1 , Figure 4 and Figure 5It can be understood that, for two adjacent first battery strings 100, the first welding ribbon 120 of one of them is located at the bottom surface of the first battery string 100, and the first welding ribbon 120 of the other is located at the top surface of the first battery string 100. Taking the first bus bar 101 being hidden under the first battery string 100 as an example, the first welding ribbon 120 located at the bottom surface of the first battery string 100 can be electrically connected to the first bus bar 101 by direct contact connection, but the first welding ribbon 120 located at the top surface of the first battery string 100 needs to be electrically connected to the first bus bar 101 through the second bridging welding ribbon 107, so as to connect the two adjacent first battery strings 100 in series through the first bus bar 101.

[0058] For the first battery string 100 that needs to be electrically connected to the first bus bar 101 through the second bridging welding strip 107, it is also necessary to avoid direct contact between the first bus bar 101 and this part of the first battery string 100. Therefore, an insulating film 108 can also be set on the surface of this part of the first battery string 100 to isolate the first bus bar 101 from the first battery string 100, and the second bridging welding strip 107 penetrates the insulating film 108 and contacts and electrically connects with the first bus bar 101.

[0059] In some embodiments, the distance between the second bridging ribbon 107 and the first cell 110 can be 0.5-3mm, for example, 0.7mm, 0.9mm, 1.5mm, 2.3mm or 2.8mm, etc. It can be understood that the greater the distance between the second bridging ribbon 107 and the first cell 110, the greater the ability to avoid short circuit between the second bridging ribbon 107 and the first cell 110, and the smaller the distance between the second bridging ribbon 107 and the first cell 110, the more the number of cells in the photovoltaic module can be increased when the size of the photovoltaic module is constant. Therefore, setting the distance between the second bridging ribbon 107 and the first cell 110 to 0.5-3mm can improve the photoelectric conversion efficiency of the photovoltaic module while taking into account the reliability of the photovoltaic module.

[0060] In other embodiments, the structure for electrically connecting the first battery string 100 and the first bus bar 101 may also be conductive glue 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 bus bar 101 overlaps with the first battery string 100, that is, the first bus bar 101 is completely hidden under the first battery string 100, or the entire first bus bar 101 will block the first battery string 100. In this way, when the area of ​​the photovoltaic module is constant, the size or number of solar cells can be increased, the effective utilization area of ​​the module can be increased, and the module power can be increased.

[0063] The first battery string 100 includes a first front side 130 and a first back side 140 opposite to each other, and the first welding ribbon 120 located at the first front side 130 is bent to the first back side 140 to contact and electrically connect with the first bus bar 101. It can be understood that, for two adjacent first battery strings 100, the first welding ribbon 120 of one is located at the first back side 140 of the first battery string 100, and the first welding ribbon 120 of the other is located at the first front side 130 of the first battery string 100, the first welding ribbon 120 located at the first back side 140 can be electrically connected to the first bus bar 101 by direct contact connection, and the first welding ribbon 120 located at the first front side 130 is bent to the first back side 140 to contact and electrically connect with the first bus bar 101, so as to connect the two adjacent first battery strings 100 in series through the first bus bar 101.

[0064] For the first battery string 100 that needs to bend the first welding strip 120 to the first back side 140, the bent first welding strip 120 cannot directly contact the first back side 140 of the first battery string 100, and the first bus bar 101 electrically connected to the bent first welding strip 120 also needs to be spaced apart from the first battery string 100 to avoid a short circuit. Therefore, an insulating adhesive film 108 may also be provided on the first back side 140 of the first battery string 100 to space the first bus bar 101 from the first battery string 100, and the bent first welding strip 120 may also be spaced apart from the first back side 140, thereby improving the reliability of the photovoltaic module while achieving contact and connection between the first bus bar 101 and the bent first welding strip 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, PERC battery (Passivated Emitter Rear Cell), IBC (Interdigitated Back Contact), TOPCon (Tunnel Oxide Passivated Contact), HIT / HJT (Heterojunction Technology) battery, solar thin film battery, laminated battery, or any combination thereof. Among them, solar thin film battery includes, but is not limited to, perovskite solar thin film battery, copper indium selenide solar thin film battery, gallium arsenide solar thin film battery, and cadmium sulfide solar thin film battery. Laminated battery includes, but is not limited to, perovskite battery superimposed on crystalline silicon battery, perovskite battery superimposed on perovskite battery, and perovskite battery superimposed on thin film battery.

[0066] The second battery string 102 is similar to the first battery string 100. The structures of two adjacent second battery strings 102 can be considered to be the same, but the surface orientations are different. The two adjacent second battery strings 102 can also be considered to have different structures. The relevant content can refer to the first battery string 100 and will not be repeated below.

[0067] In some embodiments, in the second direction Y, the spacing between the first battery cell 110 and the second battery 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. Thus, the spacing between the adjacent first battery string 100 and the second battery string 102 can be reduced, so that when the area of ​​the photovoltaic module is constant, the size or number of solar cells can be increased, the effective utilization area of ​​the module can be increased, and the module power can be increased.

[0068] In some embodiments, the width of the first bus bar 101 in the second direction Y is 4 to 16 mm, such as 5 mm, 7 mm, 10 mm or 14 mm, etc. It is understandable that the greater the width of the first bus bar 101, the greater the reliability of the connection between the first bus bar 101 and the first welding ribbon 120, and the smaller the width of the first bus bar 101, the smaller the size of the photovoltaic module, and the lower the cost.

[0069] In some embodiments, the thickness of the first bus bar 101 can be adjusted according to the width of the first bus bar 101, and the greater the width of the first bus bar 101, the smaller the thickness of the first bus bar 101 can be, so as to control the resistance of the first bus bar 101. The thickness of the first bus bar 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] Combined with reference Figure 1 , Figure 4 and Figure 5 In some embodiments, part of the fourth bus bar 106 overlaps with the second battery string 102, that is, part of the fourth bus bar 106 is hidden under the second battery string 102, or the fourth bus bar 106 blocks part of the second battery string 102. In this way, the size or number of solar cells can be increased when the area of ​​the photovoltaic module is constant, and the effective utilization area of ​​the module can be increased, thereby increasing the power of the module.

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

[0072] In some embodiments, the present invention further comprises: a plurality of second bridging ribbons 107, wherein some of the second bridging ribbons 107 are located between the fourth bus bar 106 and the second ribbon 122, so as to electrically connect the second battery string 102 to the fourth bus bar 106 through the second bridging ribbons 107. Figure 1 It can be understood that, for two adjacent second battery strings 102, the second welding ribbon 122 of one of them is located at the bottom surface of the second battery string 102, and the second welding ribbon 122 of the other is located at the top surface of the second battery string 102. Taking the fourth bus bar 106 hidden under the second battery string 106 as an example, the second welding ribbon 122 located at the bottom surface of the second battery string 102 can be electrically connected to the fourth bus bar 106 by direct contact connection, but the second welding ribbon 122 located at the top surface of the second battery string 102 needs to be electrically connected to the fourth bus bar 106 through the second bridging welding ribbon 107, so as to connect the two adjacent second battery strings 102 in series through the fourth bus bar 106.

[0073] For the second battery string 102 that needs to be electrically connected to the fourth bus bar 106 through the second bridging welding strip 107, it is also necessary to avoid direct contact between the fourth bus bar 106 and this part of the second battery string 102. Therefore, an insulating film 108 can also be set on the surface of this part of the second battery string 102 to isolate the fourth bus bar 106 from the second battery string 102, and the second bridging welding strip 107 passes through the insulating film 108 and contacts the fourth bus bar 106 for electrical connection.

[0074] In the cross section perpendicular to the first direction X and the second direction Y, the cross section of the second bridging welding strip 107 may be circular or square, that is, the second bridging welding strip 107 may be a round welding strip or a flat welding 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 bus bar 106 overlaps with the second battery string 102, that is, the fourth bus bar 106 is completely hidden under the second battery string 102, or the entire fourth bus bar 106 will block the second battery string 102. In this way, when the area of ​​the photovoltaic module is constant, 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 module can be increased.

[0077] The second battery string 102 includes a second front side 132 and a second back side 142 opposite to each other, and the second welding ribbon 122 located at the second front side 132 is bent to the second back side 142 to contact and electrically connect with the fourth bus bar 106. It can be understood that, for two adjacent second battery strings 102, the second welding ribbon 122 of one is located at the second back side 142 of the second battery string 102, and the second welding ribbon 122 of the other is located at the second front side 132 of the second battery string 102, the second welding ribbon 122 located at the second back side 142 can be electrically connected with the fourth bus bar 106 by direct contact connection, and the second welding ribbon 122 located at the second front side 132 is bent to the second back side 142 to contact and electrically connect with the fourth bus bar 106, so that the two adjacent second battery strings 102 are connected in series through the fourth bus bar 106.

[0078] For the second battery string 102 that needs to bend the second welding strip 122 to the second back side 142, the bent second welding strip 122 cannot directly contact the second back side 142 of the second battery string 102, and the fourth bus bar 106 electrically connected to the bent second welding strip 122 also needs to be spaced apart from the second battery string 102 to avoid a short circuit. Therefore, an insulating adhesive film 108 may be further 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 the bent second welding strip 122 may also be spaced apart from the second back side 142, thereby improving the reliability of the photovoltaic module while achieving contact and connection between the fourth bus bar 106 and the bent second welding strip 122.

[0079] In some embodiments, the width of the fourth bus bar 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 understandable that the greater the width of the fourth bus bar 106, the greater the reliability of the connection between the fourth bus bar 106 and the second welding ribbon 122, and the smaller the width of the fourth bus bar 106, the smaller the size of the photovoltaic module, and the lower the cost.

[0080] In some embodiments, the thickness of the fourth bus bar 106 can be adjusted according to the width of the fourth bus bar 106, and the larger the width of the fourth bus bar 106, the smaller the thickness of the fourth bus bar 106 can be, so as to control the resistance of the fourth bus bar 106. The thickness of the fourth bus bar 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 relative to each other, the second battery string 102 includes a second front side 132 and a second back side 142 relative to each other, the first bus bar 101 is located at the first back side 140, and / or the fourth bus bar 106 is located at the second back side 142. By arranging the first bus bar 101 to be located at the first back side 140, and / or the fourth bus bar 106 to be located at the second back side 142, it is possible to avoid the first bus bar 101 affecting the light absorption of the first battery string 100, and / or the fourth bus bar 106 affecting the light absorption of the second battery string 102.

[0082] In some embodiments, the first cell 110 and the second cell 112 are single-sided cells, then the first front side 130 and the second front side 132 can be used as light-receiving surfaces for receiving incident light, and the first back side 140 and the second back side 142 can be used as backlight surfaces. In some embodiments, the first cell 110 and the second cell 112 are double-sided cells, then the first front side 130, the second front side 132, the first back side 140 and the second back side 142 can all be used as light-receiving surfaces, and can all be used to receive incident light. It can be understood that the backlight surface referred to in the embodiments of the present disclosure can also receive incident light, but the degree of receiving the incident light is weaker than the degree of receiving the incident light by the light-receiving surface, and therefore is defined as the backlight surface.

[0083] In some embodiments, the structures of the first bus bar 101 and the fourth bus bar 106 may be the same, thereby reducing the specifications of the photovoltaic module materials and lowering the process difficulty of photovoltaic module manufacturing.

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

[0085] Combined with reference Figure 2 , Figure 8 and Fig. 9 ,in, Figure 8 for Figure 2 The cross-section view in the BB1 ​​direction, Fig. 9 for Figure 2 Cross-sectional view along the BB2 direction.

[0086] In some embodiments, the third bus bar 104 is located on the first back side 140 and the second back side 142. In this way, when the area of ​​the photovoltaic module is constant, 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 bus bar 104 can be avoided from blocking the light absorption of the first battery string 100 and the second battery string 102, thereby improving the photoelectric conversion efficiency of the photovoltaic module.

[0087] In some embodiments, the photovoltaic module may also include: a third welding ribbon 109, a third welding ribbon 109 connected in parallel with a first battery string 100 and a second battery string 102, the third welding ribbon 109 is located at the first back side 140 and the second back side 142, and is in contact with and electrically connected to the third bus bar 104; a fourth welding ribbon 200, a fourth welding ribbon 200 connected in parallel with a first battery string 100 and a second battery string 102, the fourth welding ribbon 200 is located at the first front side 130 and the second front side 132, and is spaced from and electrically connected to the third bus bar 104; wherein the third welding ribbon 109 and the fourth welding ribbon 200 are connected in parallel with different first battery strings 100 and second battery strings 102, and the fourth welding ribbon 200 is electrically connected to the bridging welding ribbon 105, so as to be electrically connected to the third bus bar 104 through the bridging welding ribbon 105.

[0088] For the first battery string 100 and the second battery string 102 that need to be connected in parallel, the third welding strip 109 located on the first back side 140 and the second back side 142 and the fourth welding 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 welding strip 109 located on the first back side 140 and the second back side 142 can directly contact and electrically connect with the third bus bar 104, and the fourth welding strip 200 located on the first front side 130 and the second front side 132 is spaced from the third bus bar 104, and needs to be electrically connected to the third bus bar 104 through the bridging welding strip 105. By setting the bridging welding strip 105, the fourth welding 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 welding ribbon, separating the third bus bar 104 from the first battery string 100 and the second battery string 102.

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

[0091] In some embodiments, the insulating film 108 can be a two-layer structure, one layer covering the first back side 140, and the other layer covering the second back side 142, thereby reserving an extension space for the bridging welding strip 105 in the middle part, thereby facilitating the contact between the bridging welding strip 105 and the third bus bar 104; in other embodiments, holes can be made in the parts corresponding to the insulating film 108 and the bridging welding strip 105, so that the bridging welding strip 105 can pass through these through holes and contact and electrically connect with the third bus bar 104.

[0092] As for the bridging welding strip 105 , the bridging welding strip 105 penetrates the insulating adhesive film 108 and contacts and electrically connects with the third bus bar 104 .

[0093] In some embodiments, the width of the third bus bar 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 understandable that the greater the width of the third bus bar 104, the greater the reliability of the connection between the third bus bar 104 and the third welding strip and the fourth welding strip, and the smaller the width of the third bus bar 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 bus bar 104 projected on the surface of the first battery string 100 is 1 to 7 mm, for example, 2 mm, 3 mm, 4 mm, 5 mm or 6 mm, and the width of the third bus bar 104 projected on the surface of the second battery string 102 is 1 to 7 mm, for example, 2 mm, 3 mm, 4 mm, 5 mm or 6 mm, etc. In other words, the overlapping width between the third bus bar 104 and the first battery string 100 is 1 to 7 mm, and the overlapping width between the third bus bar 104 and the second battery string 102 is 1 to 7 mm. The larger the width of the overlapping portion of the third bus bar 104 with the first battery string 100 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 third bus bar 104 with the first battery string 100 and the second battery string 102, the easier it is for the third bus bar 104 to be electrically connected to the bridging welding strip 105.

[0095] In some embodiments, the thickness of the third bus bar 104 can be adjusted according to the width of the third bus bar 104, and the greater the width of the third bus bar 104, the smaller the thickness of the third bus bar 104 can be, so as to control the resistance of the third bus bar 104. The thickness of the third bus bar 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 bus bar 101 may be smaller than the width of the third bus bar 104. It is understood that the first bus bar 101 is only electrically connected to the first battery string 100, and the third bus bar 104 needs to be electrically connected to the first battery string 100 and the second battery string 102. Therefore, setting the width of the first bus bar 101 shorter can reduce costs and reduce the size of the photovoltaic module. Similarly, the width of the fourth bus bar 106 can also be smaller than the third bus bar 104.

[0097] Combined with reference Figure 1 and Fig.10 ,in, Fig.10 for Figure 1 Cross-section along CC1 direction.

[0098] In some embodiments, the cross-sectional pattern of the first bus bar 101, the third bus bar 104 and / or the fourth bus bar 106 in the third direction is a target pattern, and the target pattern includes: a first extension portion 116, the first extension portion 116 extends along the first direction X; a second extension portion 126, the second extension portion 126 extends along the first direction X, and the second extension portion 126 is staggered from the first extension portion 116 in the first direction X and the third direction; a connecting portion 136, one end of the connecting portion 136 is in contact with and connected to the first extension portion 116, and the other end is in contact with and connected to the second extension portion 126. In other words, the cross-sectional pattern of the first bus bar 101, the third bus bar 104 and / or the fourth bus bar 106 in the third direction is similar to lightning, so that the first bus bar 101, the third bus bar 104 and / or the fourth bus bar 106 can reserve a space between the first battery string 100 and the second battery string 102, thereby facilitating the assembly of the entire photovoltaic module.

[0099] It can be understood that in some embodiments, an insulating film 108 is also included. The insulating film 108 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 bus bar 101, the third bus bar 104 and / or the fourth bus bar 106 are arranged to have a lightning-like cross-sectional pattern in the third direction, and space for the insulating film 108 can also be reserved.

[0100] Combined with reference Figure 1 and Fig.11 , Fig.11 Another embodiment of the present disclosure provides Figure 1 Cross-sectional view along CC1 direction.

[0101] In some embodiments, the thickness of the first extension portion 116 may be greater than the thickness of the second extension portion 126 , thereby reducing the height difference between the bottom surfaces of the first extension portion 116 and the second extension portion 126 , thereby facilitating the subsequent installation of the packaging film and the cover.

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

[0103] The disclosed embodiment provides a photovoltaic module. On the one hand, for the output of the photovoltaic module, the first battery string 100 and the second battery string 102 serve as the basis for providing power to the photovoltaic module, and multiple first battery strings 100 are connected in series through the first bus bar 101 and the third bus bar 104, and multiple second battery strings 102 are connected in series through the fourth bus bar 106 and the third bus bar 104, and the first battery string 100 and the second battery string 102 are connected in parallel through the second bus bar 103, and output is performed through the second bus bar 103. The second bus bar 103 is set between the first battery string 100 and the second battery string 102, that is, the second bus bar 103 is set in the middle of the photovoltaic module, which can facilitate the wiring of the photovoltaic module and the output of the photovoltaic module. On the other hand, by setting the third bus bar 104 to at least partially overlap the first cell string 100 and the second cell string 102, the spacing between the first cell string 100 and the second cell string 102 in the second direction Y can be reduced, so that when the area of ​​the photovoltaic module is constant, 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 module can be increased. Hiding the third bus bar 104 under the first cell string 100 and the second cell string 102 will cause the problem that one of the adjacent first cell string 100 or the adjacent second cell string 102 is convenient to be electrically connected to the third bus bar 104, while the other is not convenient to be electrically connected to the third bus bar 104. Therefore, a bridging welding strip 105 is also provided, and the part of the first cell string 100 or the second cell string 102 that is not convenient to be electrically connected to the third bus bar 104 is connected to the third bus bar 104 through the bridging welding strip 105, so as to improve the performance of the photovoltaic module while reducing the difficulty of the photovoltaic module manufacturing process.

[0104] Those skilled in the art can understand that the above-mentioned embodiments are specific examples for implementing the present disclosure, and in practical applications, various changes can be made to them in form and detail without departing from the spirit and scope of the embodiments of the present disclosure. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the embodiments of the present disclosure, so the protection scope of the embodiments of the present disclosure shall be based on the scope defined in the claims.

Claims

1. A photovoltaic module, characterized in that: include: A plurality of first battery strings arranged along a first direction, wherein the first battery strings include a plurality of first battery cells arranged along a second direction and first welding strips connecting adjacent first battery cells in series; A first bus bar, the first bus bar is located at one end of the first battery string along the second direction and is electrically connected to the first welding strips of two adjacent first battery strings; A plurality of second battery strings arranged along the first direction, the second battery strings comprising a plurality of second battery sheets arranged along the second direction and second welding strips connecting adjacent second battery sheets in series, a second battery string being spaced apart from and facing a first battery string along the second direction, and the second battery string being located on a side of the first battery string away from the first bus bar; A second bus bar, the second bus bar is located between a portion of the first battery string and the second battery string, and the second bus bar connects the first battery string and the second battery string facing each other in parallel; a plurality of third bus bars arranged along the first direction, the third bus bars being located at an end of the first battery string close to the second battery string, one of the third bus bars being connected in series with two adjacent first battery strings and two adjacent second battery strings, and the third bus bar at least partially overlapping with the first battery string and the second battery string; a plurality of bridging welding strips arranged along the first direction, the bridging welding strips being in contact and connected with a portion of the third bus bars, and being used to electrically connect the third bus bar with one of the first battery strings and one of the second battery strings; A fourth bus bar, the fourth bus bar is located at a side of the second battery string away from the first battery string, and is electrically connected to the second welding strips of two adjacent second battery strings.

2. The photovoltaic module according to claim 1, characterized in that: 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 bus bar is located at the first back side and the second back side.

3. The photovoltaic module according to claim 2, characterized in that: Also includes: A third welding strip, wherein the third welding strip is connected in parallel with the first battery string and the second battery string, and the third welding strip is located on the first back surface and the second back surface, and is in contact with and electrically connected to the third bus bar; A fourth welding strip, wherein the fourth welding strip is connected in parallel to the first battery string and the second battery string, and the fourth welding strip is located on the first front surface and the second front surface, and is spaced from and electrically connected to the third bus bar; The third welding strip and the fourth welding strip are connected in parallel to different first battery strings and second battery strings, and the fourth welding strip is electrically connected to the bridging welding strip so as to be electrically connected to the third bus bar through the bridging welding strip.

4. The photovoltaic module according to claim 3, characterized in that: Also includes: An insulating adhesive film is located on the first back side and the second back side of the first battery string and the second battery string connected in parallel by the fourth welding ribbon, and separates the third bus bar from the first battery string and the second battery string.

5. The photovoltaic module according to claim 1, characterized in that: The cross-sectional pattern of the first bus bar, the third bus bar and / or the fourth bus bar in the third direction is a target pattern, and the target pattern includes: a first extending portion, the first extending portion extending along the first direction; a second extending portion, the second extending portion extending along the first direction, and the second extending portion and the first extending portion are staggered in the first direction and the third direction; A connecting portion, one end of which is in contact and connected with the first extending portion, and the other end of which is in contact and connected with the second extending portion.

6. The photovoltaic module according to claim 1, characterized in that: A portion of the first bus bar overlaps with the first battery string, and a portion of the fourth bus bar overlaps with the second battery string.

7. The photovoltaic module according to claim 6, characterized in that: Also includes: A plurality of second bridging welding strips, some of which are located between the first bus bar and the first welding strip, so as to electrically connect the first battery string to the first bus bar through the second bridging welding strip, and some of which are located between the fourth bus bar and the second welding strip, so as to electrically connect the second battery string to the fourth bus bar through the second bridging welding strip.

8. The photovoltaic module according to claim 1, characterized in that: The first bus bar overlaps with the first battery string, and the fourth bus bar overlaps with the second battery string.

9. The photovoltaic module according to claim 8, characterized in that: The first battery string includes a first front side and a first back side relative to each other, the second battery string includes a second front side and a second back side relative to each other, the first welding strip located on the first front side is bent to the first back side to contact and electrically connect with the first bus bar, and the second welding strip located on the second front side is bent to the second back side to electrically connect with the fourth bus bar.

10. The photovoltaic module according to claim 1, characterized in that: Along the second direction, the width of the third bus bar projected on the surface of the first battery string is 1 to 7 mm, and the width of the third bus bar projected on the surface of the second battery string is 1 to 7 mm.

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