Photovoltaic module

Abstract

The embodiment of the invention relates to the field of photovoltaic technology, and provides a photovoltaic module, the photovoltaic module comprises a battery string, an insulating layer, a bus bar and a conductive bridging part, the battery string comprises a plurality of battery pieces, the back surface of each battery piece is provided with a welding strip, and the plurality of battery pieces are connected in series through the welding strips; the insulating layer is arranged on one side, far away from the battery piece, of the welding strip, and the insulating layer is provided with an avoiding area, so that part of the welding strip is exposed from the avoiding area to form a welding strip exposing part; the bus bar is arranged on one side of the insulating layer away from the solder strip; the conductive bridging part is arranged between the bus bar and the solder strip exposing part, so that the bus bar and the solder strip exposing part are conductively connected through the conductive bridging part. The embodiment of the invention is at least beneficial to improving the maximum output power of the back contact battery assembly.

Description

Technical Field

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

[0002] The front of the back contact (BC) cell is free of grid lines, which can maximize the use of incident light, reduce optical losses, and have a higher short-circuit current, thereby increasing the maximum output power of the back contact cell module. In existing back contact cell modules, there are still visible bus bars on the front of the back contact cell module, which occupy part of the module area, reduce the laying area of ​​the battery cells, and severely limit the maximum output power of the back contact cell module. Summary of the invention

[0003] The embodiments of the present disclosure provide a photovoltaic module, which is at least beneficial for improving the maximum output power of the back-contact battery module.

[0004] According to some embodiments of the present disclosure, on one hand, a photovoltaic assembly is provided, including:

[0005] A battery string, the battery string comprising a plurality of battery cells, a welding strip being arranged on the back of each battery cell, so as to connect the plurality of battery cells in series through the welding strip;

[0006] An insulating layer, the insulating layer is arranged on a side of the soldering strip away from the battery cell, and the insulating layer is provided with an avoidance area so that a portion of the soldering strip is exposed from the avoidance area to form a soldering strip exposed portion;

[0007] A bus bar, the bus bar is arranged on a side of the insulating layer away from the welding strip;

[0008] A conductive bridge portion is disposed between the bus bar and the solder strip exposed portion so as to conductively connect the bus bar and the solder strip exposed portion through the conductive bridge portion.

[0009] In some embodiments, the conductive bridging portion is a bridging connector or a conductive adhesive.

[0010] In some embodiments, the conductive bridging portion is a bridging connector, wherein:

[0011] The bridging connector and the exposed portion of the welding strip are integrally formed; and / or,

[0012] The width of the bridging connector is greater than the width of the welding strip.

[0013] In some embodiments, the insulating layer includes a coating layer, the coating layer is disposed on the battery string, the coating layer covers the back side of the battery cell and the welding strip, the coating layer is provided with an opening, and the opening forms the avoidance area.

[0014] In some embodiments, the insulating layer further includes an insulating spacer layer, the insulating spacer layer is disposed between the coating layer and the bus bar, and the insulating spacer layer is provided with a avoidance structure communicating with the opening.

[0015] In some embodiments, an insulating glue is provided between the soldering strip and the back side of the battery cell, and a dimension of the insulating glue in the width direction of the soldering strip is greater than or equal to a dimension of the opening in the width direction of the soldering strip, so that a projection of the opening on the back side of the battery cell is located on the insulating glue.

[0016] In some embodiments, the coating layer is extended along the length direction of the battery string, and the size of the coating layer in the length direction of the battery string is equal to the length of the battery string; or,

[0017] The coating layer includes a plurality of coating sub-layers, and the plurality of coating sub-layers are arranged in a one-to-one correspondence with the plurality of battery cells in the battery string, and each of the coating sub-layers covers the back side of a corresponding battery cell.

[0018] In some embodiments, the insulating spacer layer is arranged in a strip shape extending along the length direction of the busbar, and the insulating spacer layer is provided with avoidance holes corresponding to the openings, and the avoidance holes form the avoidance structure.

[0019] In some embodiments, the insulating spacer layer includes a plurality of insulating sublayers spaced apart along the length direction of the busbar, and the opening is located between two adjacent insulating sublayers to form the avoidance structure between the two adjacent insulating sublayers.

[0020] In some embodiments, a plurality of the openings are arranged at intervals along the length direction of the busbar, and the insulating sublayers are arranged on both sides of each opening in the length direction of the busbar.

[0021] The technical solution provided by the embodiments of the present disclosure has at least the following advantages:

[0022] The busbar of the photovoltaic module is hidden on the back of the battery cell, and the busbar does not occupy the area on the front of the photovoltaic module. This can maximize the laying area of ​​the battery cell and increase the illuminated area on the front of the photovoltaic module, thereby increasing the maximum output power of the photovoltaic module. Adding a conductive bridge part in the contact area between the busbar and the welding ribbon can not only effectively reduce the risk of hidden cracks and fragments of the battery cell in the subsequent lamination process, but also reduce the possibility of poor soldering between the busbar and the welding ribbon. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] 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.

[0024] Figure 1 It is a schematic diagram of the structure of a back contact battery assembly in the prior art;

[0025] Figure 2 A schematic diagram of the structure of a photovoltaic module provided by an embodiment of the present disclosure;

[0026] Figure 3 for Figure 2 A cross-sectional view of a photovoltaic module;

[0027] Figure 4 for Figure 3 A partial enlarged view of the middle A;

[0028] Figure 5 for Figure 2 Schematic diagram of the structure of the photovoltaic module after removing the busbar;

[0029] Figure 6 for Figure 2 Schematic diagram of the structure of the photovoltaic module after removing the busbar and insulating spacer layer;

[0030] Figure 7 A schematic diagram of the structure of another photovoltaic module provided by an embodiment of the present disclosure;

[0031] Figure 8 for Figure 7 Schematic diagram of the structure of the photovoltaic module after removing the busbar;

[0032] Fig. 9 A schematic structural diagram of an opening in another photovoltaic module provided by an embodiment of the present disclosure. DETAILED DESCRIPTION

[0033] As can be seen from the background technology, reference Figure 1 In the existing back contact battery assembly 1000A, the head and tail bus bars 100A and the middle bus bar 200A are still visible on the front of the back contact battery assembly 1000A. In this way, when the size of the back contact battery assembly 1000A is fixed, the head and tail bus bars 100A and the middle bus bar 200A occupy part of the front area of ​​the back contact battery assembly 1000A, thereby reducing the laying area of ​​the battery cell 300A, which seriously limits the maximum output power of the back contact battery assembly 1000A.

[0034] The present disclosure implements a photovoltaic module, in which the bus bar of the photovoltaic module is hidden on the back side of the battery cell, and the bus bar does not occupy the area of ​​the front side of the photovoltaic module. This can maximize the laying area of ​​the battery cell and increase the illuminated area of ​​the front side of the photovoltaic module, thereby improving the maximum output power of the photovoltaic module. A conductive bridging portion is added to the contact area between the bus bar and the welding strip, which can not only effectively reduce the risk of hidden cracks and fragments of the battery cell in the subsequent lamination process, but also reduce the possibility of poor soldering between the bus bar and the welding strip.

[0035] In the description of the embodiments of the present application, 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 application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined. Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0036] 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 application. The appearance of the phrase in various locations 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.

[0037] In the description of the embodiments of the present application, 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 can 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.

[0038] In the description of the embodiments of the present application, the orientation or positional relationship indicated by the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the embodiments of the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present application. For example, if the device or element in the figure is inverted, then the element described as being "below" or "below" or "below" or "bottom" of other elements or features will be oriented "above" or "top" of the other elements or features. Therefore, the term "below" may cover both the above and below orientations depending on the context in which the term is used, which will be obvious to a person of ordinary skill in the art. The material can be oriented in other ways (e.g., rotated 90 degrees, inverted, flipped), and the spatially relative descriptors used herein can be interpreted accordingly.

[0039] In the description of the embodiments of the present application, 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 application can be understood according to the specific circumstances.

[0040] In the accompanying drawings corresponding to the embodiments of the present application, the thickness and area of ​​the layers are exaggerated for better understanding and ease of description. In addition, when describing that a component is "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.

[0041] In the description of the embodiments of the present application, when a certain component "includes" another component, unless otherwise specified, other components are not excluded, and other components may be further included. A second component is formed or provided above or on the first component, or a second component is formed or provided on the surface of the first component, or a second component is formed or provided on one side of the first component, which may include an embodiment in which the first component and the second component are in direct contact, and may also include an embodiment in which an additional component may be provided between the first component and the second component, so that the first component and the second component may not be in direct contact. For the sake of simplicity and clarity, various components may be drawn arbitrarily in different proportions. In the accompanying drawings, some layers / components may be omitted for simplicity. Unless otherwise specified, a second component is formed or provided on the surface of the first component, which means that the first component is in direct contact with the second component. Among them, the above-mentioned "component" may refer to a layer, a film, an area, a part, a structure, etc.

[0042] 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.

[0043] 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.

[0044] Figures 2 to 9 Schematic diagram of the structures of various photovoltaic modules provided in the embodiments of the present disclosure.

[0045] refer to Figures 2 to 4 The photovoltaic module 1000 includes a battery string 100, an insulating layer 300, a bus bar 400 and a conductive bridge portion 500. The battery string 100 includes a plurality of battery cells 110. A welding strip 200 is arranged on the back of each battery cell 110 so as to connect the plurality of battery cells 110 in series through the welding strip 200. The insulating layer 300 is arranged on a side of the welding strip 200 away from the battery cell 110. The insulating layer 300 is provided with an avoidance area 310 so as to allow part of the welding strip 200 to be exposed from the avoidance area 310 to form a welding strip exposed portion 210. The bus bar 400 is arranged on a side of the insulating layer 300 away from the welding strip 200. The conductive bridge portion 500 is arranged between the bus bar 400 and the welding strip exposed portion 210 so as to conductively connect the bus bar 400 to the welding strip exposed portion 210 through the conductive bridge portion 500.

[0046] Specifically, the photovoltaic module 1000 is a back contact battery module, and the photovoltaic module 1000 includes a plurality of battery strings 100 connected in series, and each battery string 100 includes a plurality of battery cells 110 connected in series. The battery cell 110 is generally a sheet structure, and the battery cell 110 has a front side (or light absorbing side) and a back side that are opposite to each other in the thickness direction of the battery cell 110. The front side of the battery cell 110 can absorb light energy and convert the light energy into electrical energy. The back side of the battery cell 110 is provided with a first grid line and a second grid line, and one of the first grid line and the second grid line is a positive grid line, and the other is a negative grid line. A plurality of welding strips 200 are arranged on the back of each battery cell 110, and the welding strips 200 are extended along the length direction of the battery string 100 (i.e., the arrangement direction of the plurality of battery cells 110 in the battery string 100), and the plurality of welding strips 200 include a plurality of first welding strips 200a and a plurality of second welding strips 200b, and the plurality of first welding strips 200a and the plurality of second welding strips 200b are alternately arranged on the back of the battery cell 110 along the width direction of the battery string 100. The first welding strip 200a is conductively connected to the first grid line, and the second welding strip 200b is conductively connected to the second grid line, so that the current of the first grid line can be conducted by the first welding strip 200a, and the current of the second grid line can also be conducted by the second welding strip 200b, and the plurality of battery cells 110 in the battery string 100 are connected in series through the first welding strip 200a and the second welding strip 200b.

[0047] The insulating layer 300 is disposed on the side of the welding ribbon 200 away from the battery cell 110, and the insulating layer 300 is provided with an avoidance area 310, and the portion of the welding ribbon 200 and the avoidance area 310 opposite to each other in the thickness direction of the battery cell 110 is the welding ribbon exposed portion 210, and the avoidance area 310 exposes the welding ribbon exposed portion 210 of the welding ribbon 200, that is, the welding ribbon exposed portion 210 is not covered by the insulating layer 300, and the welding ribbon 200 is covered by the insulating layer 300 except for the welding ribbon exposed portion 210. The bus bar 400 is disposed on the side of the insulating layer 300 away from the welding ribbon 200, and a portion of the bus bar 400 is spaced and opposite to the welding ribbon exposed portion 210 in the thickness direction of the battery cell 110. A conductive bridge portion 500 is provided at the avoidance area 310 of the insulating layer 300, and the conductive bridge portion 500 is located between the solder strip exposed portion 210 and the bus bar 400. The conductive bridge portion 500 is respectively conductively connected to the solder strip exposed portion 210 and the bus bar 400, so that the bus bar 400 is conductively connected to the solder strip 200 through the conductive bridge portion 500. In this way, a conductive bridge portion 500 is added to the contact position between the bus bar 400 and the solder strip 200, so that the contact position between the bus bar 400 and the solder strip 200 can become flat, thereby improving the stress concentration and local deformation of the battery cell 110 generated in the subsequent lamination process.

[0048] The bus bar 400 is electrically connected to the welding strip 200, specifically, the bus bar 400 is electrically connected to one of the first welding strip 200a and the second welding strip 200b. Figures 2 to 4 In some embodiments, the insulating layer 300 is provided with a avoidance area 310 corresponding to the first welding strip 200a, and the bus bar 400 is conductively connected to the first welding strip 200a through the conductive bridge portion 500. For example, in other embodiments, the insulating layer 300 is provided with a avoidance area 310 corresponding to the second welding strip 200b, and the bus bar 400 is conductively connected to the second welding strip 200b through the conductive bridge portion 500. The following will take the bus bar 400 conductively connected to the first welding strip 200a through the conductive bridge portion 500 as an example for description.

[0049] The busbar 400 of the photovoltaic module 1000 is hidden on the back side of the battery cell 110, and the busbar 400 does not occupy the area on the front side of the photovoltaic module 1000. This can maximize the laying area of ​​the battery cell 110 and increase the illuminated area on the front side of the photovoltaic module 1000, thereby improving the maximum output power of the photovoltaic module 1000. A conductive bridging portion 500 is added to the contact area between the busbar 400 and the welding ribbon 200, which can not only effectively reduce the risk of hidden cracks and fragments of the battery cell 110 in the subsequent lamination process, but also reduce the possibility of poor soldering between the busbar 400 and the welding ribbon 200.

[0050] The embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings.

[0051] The bus bar 400 and the welding strip 200 are conductively connected via a conductive bridging portion 500. There are many specific ways to configure the conductive bridging portion 500. For example, the conductive bridging portion 500 may be a bridging connector 500a such as a section of welding strip or a metal part; the conductive bridging portion 500 may also be a conductive adhesive; the conductive bridging portion 500 may also be a combination of a bridging connector 500a and a conductive adhesive.

[0052] refer to Figure 3 to Figure 4 In some embodiments, the conductive bridge portion 500 is a bridge connector 500a, and the bridge connector 500a is a section of a welding strip. Using a section of a welding strip as the conductive bridge portion 500, the configuration of the conductive bridge portion 500 is relatively simple.

[0053] When the conductive bridging portion 500 is a bridging connector 500 a , the bridging connector 500 a and the solder strip exposed portion 210 may be integrally formed; the bridging connector 500 a and the solder strip exposed portion 210 may also be separate bodies.

[0054] The thickness of the bridging connector 500a is the dimension of the bridging connector 500a in the thickness direction of the solder strip 200. The height difference between the bus bar 400 and the solder strip 200 is equal to or approximately equal to the thickness of the bridging connector 500a, so that the contact position between the bus bar 400 and the solder strip 200 can be relatively flat.

[0055] The length of the bridge connector 500a is the dimension of the bridge connector 500a in the length direction of the solder strip 200, and the length of the bridge connector 500a is less than or equal to the length of the solder strip exposed portion 210. Figure 3 to Figure 4 In some embodiments, the length of the bridge connector 500a is equal to the length of the exposed portion 210 of the solder strip. In this way, maximizing the length of the bridge connector 500a is not only conducive to increasing the effective conductive area between the bus bar 400 and the solder strip 200, but also can avoid the appearance of a gap between the bus bar 400 and the solder strip 200 in the length direction of the solder strip 200, so that the contact position between the bus bar 400 and the solder strip 200 can be relatively flat.

[0056] The width of the bridge connector 500a is the size of the bridge connector 500a in the width direction of the solder strip 200. The width of the bridge connector 500a may be greater than or equal to the width of the solder strip 200; the width of the bridge connector 500a may also be less than the width of the solder strip 200. Figure 3 and Figure 4 In some embodiments, the width of the bridge connector 500a is greater than the width of the welding strip 200. The welding strip 200 is usually set to be of equal width, and the width of the welding strip 200 is the width of the welding strip exposed portion 210. In this way, the width of the bridge connector 500a is set slightly larger than the width of the welding strip exposed portion 210, which is not only conducive to increasing the effective conductive area between the bus bar 400 and the welding strip 200, but also can avoid the appearance of a gap between the bus bar 400 and the welding strip 200 in the width direction of the welding strip 200, so that the contact position between the bus bar 400 and the welding strip 200 can be relatively flat.

[0057] refer to Figure 2 , Figure 5 and Figure 6 , the battery string 100 is usually provided with a plurality of first welding strips 200a along the width direction of the battery string 100, and the plurality of first welding strips 200a are conductively connected through the bus bar 400. For example, referring to Figure 2 , Figure 5 and Figure 6In some embodiments, the insulating layer 300 is provided with a plurality of avoidance areas 310 arranged at intervals along the length direction of the bus bar 400, so that the battery string 100 is formed with a plurality of solder strip exposed portions 210 arranged at intervals along the length direction of the bus bar 400, and a plurality of conductive bridge portions 500 are provided corresponding to the plurality of solder strip exposed portions 210 in the battery string 100, and each solder strip exposed portion 210 is conductively connected to the bus bar 400 through a corresponding conductive bridge portion 500. Among them, the length direction of the bus bar 400 is perpendicular or approximately perpendicular to the length direction of the solder strip 200. Such a configuration can make the laying method of the battery cell 110 more abundant, which is conducive to increasing the laying area of ​​the battery cell.

[0058] refer to Figure 2 , Figure 5 and Figure 6 , the photovoltaic module 1000 generally includes a plurality of battery strings 100, and the plurality of battery strings 100 are connected in series via a bus bar 400. For example, referring to Figure 2 , Figure 5 and Figure 6 In some embodiments, multiple battery strings 100 are arranged along the length direction of the bus bar 400, and multiple battery strings 100 are connected in series through the bus bar 400. Such an arrangement can make the laying method of the battery sheet 110 more diverse, which is conducive to increasing the laying area of ​​the battery sheet.

[0059] An insulating layer 300 is provided between the bus bar 400 and the welding strip 200, and the insulating layer 300 can insulate the bus bar 400 from the second welding strip 200b and the second grid line of the battery cell 110. Since the insulating layer 300 is provided with an avoidance area 310 corresponding to the first welding strip 200a, the bus bar 400 can be conductively connected to the first welding strip 200a through the conductive bridge portion 500 provided at the avoidance area 310.

[0060] There are many specific ways to set the insulating layer 300. For example, the insulating layer 300 can be an insulating glue, an insulating tape, or an insulating film. Figure 2 , Figure 5 and Figure 6 In some embodiments, the insulating layer 300 includes a coating layer 320 , which is disposed on the battery string 100 , and covers the back side of the battery cell 110 and the welding strip 200 . The coating layer 320 is provided with an opening 321 , and the opening 321 forms an avoidance area 310 .

[0061] Specifically, the coating layer 320 is an insulating film, and the coating layer 320 is provided with a plurality of openings 321, and the plurality of openings 321 respectively form a plurality of avoidance areas 310. The specific shape of the openings 321 may not be particularly limited, and the openings 321 may be provided in the shape of a square hole, a circular hole, or a diamond hole. Figure 5 and Figure 6In some embodiments, the opening 321 is a square hole.

[0062] The coating layer 320 can be disposed on the back of the battery cell 110 by low-temperature coating technology. For example, a layer of coating layer 320 is first laid and the coating layer 320 is perforated; the welding tape 200 is placed on the coating layer 320 after positioning; the battery cell 110 is then placed; and finally heating and pressurizing are performed so that the welding tape 200 is fixed on the battery cell 110 by the coating layer 320. The coating layer 320 is disposed on the back of the battery cell 110 by the low-temperature coating technology, which can reduce the warping of the battery cell 110, and the coating layer 320 can protect most of the grid line area of ​​the battery cell 110, so as to prevent the tin explosion caused by the welding of the bus bar 400 from short-circuiting the battery cell 110. Among them, the specific material of the coating layer 320 can be set according to actual conditions. For example, the coating layer 320 can be EVA (ethylene-vinyl acetate copolymer) film, POE (polyethylene octene elastomer) film, EP film (EVA and POE two-layer co-extruded film) or EPE film (EVA and POE three-layer co-extruded film), etc.

[0063] The coating layer 320 covers the back side of each battery cell 110 in the battery string 100, and there are many specific configuration methods for the coating layer 320. For example, referring to Figure 6 In some embodiments, the coating layer 320 includes a plurality of coating sub-layers 322, and the plurality of coating sub-layers 322 are arranged in a one-to-one correspondence with the plurality of battery cells 110 in the battery string 100, and each coating sub-layer 322 covers the back side of a corresponding battery cell 110. The shape and size of the coating sub-layer 322 are adapted to the shape and size of the battery cell 110, and the plurality of coating sub-layers 322 are respectively covered on the back side of the plurality of battery cells 110 in the battery string 100, and the plurality of coating sub-layers 322 are not connected into a whole. Thus, the coating layer 320 is formed by a plurality of sheet-shaped coating sub-layers 322, so that the setting area of ​​the coating layer 320 can be reduced, and the amount of the coating layer 320 used can be reduced.

[0064] For example, in other embodiments, the coating layer 320 is extended along the length direction of the battery string 100, and the size of the coating layer 320 in the length direction of the battery string 100 is equal to the length of the battery string 100. The length of the coating layer 320 is equal to or approximately equal to the length of the battery string 100, which is not only conducive to ensuring that the back side of each battery cell 110 in the battery string 100 can be completely covered by the coating layer 320, but also allows the welding ribbon 200 connecting two adjacent battery cells 110 to be completely covered by the coating layer 320.

[0065] refer to Figures 2 to 4In some embodiments, the insulating layer 300 further includes an insulating spacer layer 330 , which is disposed between the coating layer 320 and the bus bar 400 , and the insulating spacer layer 330 is provided with a avoidance structure 331 communicating with the opening 321 .

[0066] Specifically, an insulating spacer layer 330 is provided between the coating layer 320 and the bus bar 400, so that the thickness of the insulating layer 300 at the connection between the bus bar 400 and the welding strip 200 is the sum of the thickness of the coating layer 320 and the thickness of the insulating spacer layer 330, which is conducive to ensuring that the insulating layer 300 has sufficient thickness at the connection between the bus bar 400 and the welding strip 200, thereby ensuring the insulation effect of the insulating layer 300. Among them, the insulating spacer layer 330 can be an insulating glue, an insulating tape or an insulating film.

[0067] The thermoplasticity of the coating layer 320 is usually better than that of the insulating spacer layer 330, which not only ensures that the coating layer 320 has a good coating effect, but also helps to ensure that the insulating layer 300 has a sufficient thickness at the connection between the bus bar 400 and the welding ribbon 200 through the provision of the insulating spacer layer 330. The specific material of the insulating spacer layer 330 can be set according to actual conditions, for example, the insulating spacer layer 330 can be a PET (polyethylene terephthalate) film or a PI (polyimide) film.

[0068] The insulating spacer layer 330 is used to ensure that the insulating layer 300 has sufficient thickness at the connection between the bus bar 400 and the welding ribbon 200, and the specific thickness of the insulating spacer layer 330 can be set according to actual conditions. In some embodiments, the thickness of the insulating spacer layer 330 is 0.03-0.2 mm.

[0069] Specifically, the thickness of the insulating spacer layer 330 is 0.03 to 0.2 mm. For example, the thickness of the insulating spacer layer 330 can be 0.03 mm, 0.04 mm, 0.05 mm, 0.06 mm, 0.07 mm, 0.08 mm, 0.09 mm, 0.1 mm, 0.11 mm, 0.12 mm, 0.13 mm, 0.14 mm, 0.15 mm, 0.16 mm, 0.17 mm, 0.18 mm, 0.19 mm or 0.2 mm, etc. In this way, by optimizing the value range of the thickness of the insulating spacer layer 330, it is possible to ensure that the insulating layer 300 has sufficient thickness at the connection between the bus bar 400 and the welding strip 200. This can not only prevent the thickness of the insulating spacer layer 330 from being too thin, making it inconvenient to operate when pasting the insulating spacer layer 330, and it is easy to deform when pulling, and there is a risk of damage during long-term insulation. It can also prevent the thickness of the insulating spacer layer 330 from being too thick, resulting in a large height difference between the bus bar 400 and the welding strip 200, causing the risk of hidden cracks and fragments of the battery cell 110 during the subsequent lamination process.

[0070] The insulating spacer layer 330 is disposed between the coating layer 320 and the busbar 400 . The insulating spacer layer 330 is generally arranged along the length direction of the busbar 400 . The dimension of the insulating spacer layer 330 in the width direction of the busbar 400 is greater than or equal to the width of the busbar 400 .

[0071] refer to Figure 2 and Figure 5 In some embodiments, the insulating spacer layer 330 includes a plurality of insulating sublayers 332 spaced apart along the length direction of the busbar 400 , and the opening 321 is located between two adjacent insulating sublayers 332 to form an avoidance structure 331 between the two adjacent insulating sublayers 332 .

[0072] Specifically, a single insulating sublayer 332 is arranged in a block shape, and a plurality of insulating sublayers 332 are arranged at intervals along the length direction of the busbar 400 to form an insulating spacer layer 330, and the plurality of insulating sublayers 332 and the plurality of openings 321 of the coating layer 320 are arranged alternately along the length direction of the busbar 400, and the gap between the two insulating sublayers 332 on both sides of each opening 321 forms an avoidance structure 331, so that the insulating spacer layer 330 forms a plurality of avoidance structures 331 corresponding to the plurality of openings 321 of the coating layer 320, and the spacing between two adjacent insulating sublayers 332 is greater than or equal to the size of the opening 321 in the length direction of the busbar 400. In this way, by forming the insulating spacer layer 330 with a plurality of insulating sublayers 332, the setting area of ​​the insulating spacer layer 330 can be reduced, and the amount of the insulating spacer layer 330 can be reduced.

[0073] The number of insulating sublayers 332 may be less than the number of openings 321; the number of insulating sublayers 332 may be equal to the number of openings 321; the number of insulating sublayers 332 may be greater than the number of openings 321. Figure 2 and Figure 5 In some embodiments, a plurality of openings 321 are arranged at intervals along the length direction of the busbar 400 , and each opening 321 is provided with insulating sublayers 332 on both sides of the busbar 400 in the length direction.

[0074] Specifically, the number of insulating sublayers 332 is greater than the number of openings 321, so that two insulating sublayers 332 can be distributed on both sides of each opening 321. In this way, the insulating sublayers 332 are arranged on both sides of each opening 321, which can reduce the gap between the bus bar 400 and the coating layer 320, so that the contact position between the bus bar 400 and the welding strip 200 can be relatively flat.

[0075] refer to Figure 7 and Figure 8In some embodiments, the insulating spacer layer 330 is arranged in a strip shape extending along the length direction of the busbar 400 , and the insulating spacer layer 330 is provided with avoidance holes 331 a corresponding to the openings 321 , and the avoidance holes 331 a form an avoidance structure 331 .

[0076] Specifically, the shape of the insulating spacer layer 330 is adapted to the shape of the busbar 400, and the insulating spacer layer 330 is arranged in a long strip shape. The length of the insulating spacer layer 330 is greater than or equal to the length of the busbar 400, and the width of the insulating spacer layer 330 is greater than or equal to the width of the busbar 400. For example, the length of the insulating spacer layer 330 may be slightly greater than the length of the busbar 400, and the width of the insulating spacer layer 330 may also be slightly greater than the width of the busbar 400. The insulating spacer layer 330 is provided with a plurality of avoidance holes 331a corresponding to the plurality of openings 321 of the coating layer 320, and each avoidance hole 331a is connected to a corresponding opening 321. The size of the avoidance hole 331a may be greater than or equal to the size of the opening 321, and the shape of the avoidance hole 331a is generally adapted to the shape of the opening 321. For example, refer to Figure 7 and Figure 8 In some embodiments, the avoidance hole 331a and the opening 321 are both square holes. By setting the insulating spacer layer 330 in a strip shape, a gap between the bus bar 400 and the coating layer 320 can be avoided, so that the contact position between the bus bar 400 and the welding strip 200 can be relatively flat.

[0077] The thickness of the soldering tape 200 is less than the sum of the thickness of the coating layer 320 and the thickness of the insulating spacer layer 330, and the thickness of the soldering tape 200 may be less than the thickness of the coating layer 320; the thickness of the soldering tape 200 may also be equal to the thickness of the coating layer 320; the thickness of the soldering tape 200 may also be greater than the thickness of the coating layer 320. Figure 4 In some embodiments, the surface of the exposed portion 210 of the solder strip away from the battery cell 110 is located on the side of the coating layer 320 close to the insulating spacer layer 330 , and the surface of the insulating spacer layer 330 close to the bus bar 400 is located on the side of the exposed portion 210 of the solder strip away from the battery cell 110 .

[0078] Specifically, the thickness of the welding ribbon 200 may be less than the thickness of the coating layer 320, so that the surface of the welding ribbon exposed portion 210 away from the battery cell 110 is located on the side of the coating layer 320 close to the insulating spacer layer 330, that is, the welding ribbon exposed portion 210 extends out of the opening 321 of the coating layer 320 toward the bus bar 400. The thickness of the welding ribbon 200 is less than the sum of the thickness of the coating layer 320 and the thickness of the insulating spacer layer 330, so that the surface of the insulating spacer layer 330 close to the bus bar 400 is located on the side of the welding ribbon exposed portion 210 away from the battery cell 110, that is, the portion of the welding ribbon exposed portion 210 extending out of the opening 321 is located within the avoidance structure 331 of the insulating spacer layer 330.

[0079] refer to Fig. 9 The back of the cell 110 is usually provided with an insulating glue 120, which can insulate the first grid line and the second grid line of the cell 110. Since the back of the cell 110 is provided with a coating layer 320, the coating layer 320 can protect most of the grid line area of ​​the cell 110, so that the amount of the insulating glue 120 can be reduced.

[0080] refer to Fig. 9 In some embodiments, an insulating glue 120 is arranged between the soldering ribbon 200 and the back side of the battery cell 110, and the size of the insulating glue 120 in the width direction of the soldering ribbon 200 is greater than or equal to the size of the opening 321 in the width direction of the soldering ribbon 200, so that the projection of the opening 321 on the back side of the battery cell 110 is located on the insulating glue 120.

[0081] Specifically, the size of the insulating glue 120 in the width direction of the welding strip 200 is the width of the insulating glue 120, and the size of the opening 321 in the width direction of the welding strip 200 is the width of the opening 321. The width of the opening 321 is greater than the width of the welding strip 200, and the width of the insulating glue 120 is greater than or equal to the width of the opening 321, so that the portion of the back of the battery cell 110 exposed from the opening 321 is the insulating glue 120 except for the exposed portion 210 of the welding strip, that is, the area of ​​the back of the battery cell 110 except for the exposed portion 210 of the welding strip is covered by the insulating glue 120 and the coating layer 320. In this way, the coating layer 320 has a hole to expose the exposed portion 210 of the welding strip. As long as the opening position of the coating layer 320 is set in place, the bus bar 400 is protected by the insulating glue 120 and the coating layer 320 after soldering and tinning, and there will be no problem of foreign matter overlapping the grid line of the battery cell 110, causing the battery cell 110 to short-circuit.

[0082] Those skilled in the art can understand that the above-mentioned embodiments are specific examples for realizing the present disclosure, and in practical applications, various changes can be made to them in form and details without departing from the spirit and scope 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 present disclosure, so the protection scope of the present disclosure shall be based on the scope defined in the claims.

Claims

1. A photovoltaic module, characterized in that: include: A battery string, the battery string comprising a plurality of battery cells, a welding strip being arranged on the back of each battery cell, so as to connect the plurality of battery cells in series through the welding strip; An insulating layer, the insulating layer is arranged on a side of the soldering strip away from the battery cell, and the insulating layer is provided with an avoidance area so that a portion of the soldering strip is exposed from the avoidance area to form a soldering strip exposed portion; A bus bar, the bus bar is arranged on a side of the insulating layer away from the welding strip; A conductive bridge portion is disposed between the bus bar and the solder strip exposed portion so as to conductively connect the bus bar and the solder strip exposed portion through the conductive bridge portion.

2. The photovoltaic module according to claim 1, characterized in that: The conductive bridging portion is a bridging connector or a conductive adhesive.

3. The photovoltaic module according to claim 2, characterized in that: The conductive bridging portion is a bridging connector, wherein: The bridging connector and the exposed portion of the welding strip are integrally formed; and / or, The width of the bridging connector is greater than the width of the welding strip.

4. The photovoltaic module according to claim 1, characterized in that: The insulating layer includes a coating layer, which is disposed on the battery string, covers the back side of the battery cell and the welding strip, and is provided with openings, which form the avoidance area.

5. The photovoltaic module according to claim 4, characterized in that: The insulating layer further comprises an insulating spacer layer, wherein the insulating spacer layer is arranged between the coating layer and the bus bar, and the insulating spacer layer is provided with a avoidance structure communicating with the opening.

6. The photovoltaic module according to claim 4, characterized in that: An insulating glue is arranged between the soldering strip and the back side of the battery cell, and the size of the insulating glue in the width direction of the soldering strip is greater than or equal to the size of the opening in the width direction of the soldering strip, so that the projection of the opening on the back side of the battery cell is located on the insulating glue.

7. The photovoltaic module according to claim 4, characterized in that: The coating layer is extended along the length direction of the battery string, and the size of the coating layer in the length direction of the battery string is equal to the length of the battery string; or The coating layer includes a plurality of coating sub-layers, and the plurality of coating sub-layers are arranged in a one-to-one correspondence with the plurality of battery cells in the battery string, and each of the coating sub-layers covers the back side of a corresponding battery cell.

8. The photovoltaic module according to claim 5, characterized in that: The insulating spacer layer is arranged in a strip shape extending along the length direction of the busbar, and the insulating spacer layer is provided with avoidance holes corresponding to the openings, and the avoidance holes form the avoidance structure.

9. The photovoltaic module according to claim 5, characterized in that: The insulating spacer layer includes a plurality of insulating sub-layers spaced apart along the length direction of the busbar, and the opening is located between two adjacent insulating sub-layers to form the avoidance structure between the two adjacent insulating sub-layers.

10. The photovoltaic module according to claim 9, characterized in that: A plurality of openings are arranged at intervals along the length direction of the busbar, and the insulating sublayers are arranged on both sides of each opening in the length direction of the busbar.

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