Photovoltaic module

Abstract

The embodiment of the present disclosure relates to the photovoltaic technical field, and provides a photovoltaic module, the photovoltaic module includes a cell string, an insulating layer and a bus bar, the cell string includes a plurality of cell pieces, the back surface of each cell piece is provided with a solder strip, so that the plurality of cell pieces are connected in series through the solder strip, the insulating layer is arranged on the side of the solder strip away from the cell piece, the insulating layer is provided with a avoiding area, so that part of the solder strip is exposed from the avoiding area to form a solder strip exposed part, the bus bar is arranged on the side of the insulating layer away from the solder strip, the bus bar is provided with an abutting part towards the solder strip exposed part, the abutting part is in abutment with the solder strip exposed part, so as to conductively connect the bus bar with the solder strip.The embodiment of the present disclosure is at least beneficial to improve the maximum output power of the back contact cell module.

Description

Technical Field

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

[0002] Back-contact (BC) cells have no grid lines obstructing the front, maximizing the utilization of incident light, reducing optical losses, and exhibiting higher short-circuit current, thereby increasing the maximum output power of back-contact cell modules. In existing back-contact cell modules, visible busbars still exist on the front, occupying part of the module area, reducing the cell placement area, and severely limiting the maximum output power of the back-contact cell module. Summary of the Invention

[0003] This disclosure provides a photovoltaic module that at least helps to increase the maximum output power of a back-contact battery module.

[0004] According to some embodiments of this disclosure, one aspect of this disclosure provides a photovoltaic module, including:

[0005] A battery string, comprising multiple battery cells, each battery cell having a solder strip on its back side to connect multiple battery cells in series via the solder strip;

[0006] An insulating layer is disposed on the side of the solder ribbon away from the battery cell, and the insulating layer is provided with a clearance area so that a portion of the solder ribbon is exposed from the clearance area to form a solder ribbon exposure portion;

[0007] A busbar is disposed on the side of the insulating layer away from the solder strip. The busbar has a protruding abutment portion facing the exposed portion of the solder strip, and the abutment portion abuts against the exposed portion of the solder strip to electrically connect the busbar to the solder strip.

[0008] In some embodiments, a portion of the busbar is recessed relative to the portion adjacent to the recessed portion toward the exposed solder strip, and the recessed portion of the busbar forms the abutment portion.

[0009] In some embodiments, the abutment portion is arc-shaped.

[0010] In some embodiments, the dimension of the abutment portion in the width direction of the busbar is equal to the width of the busbar.

[0011] In some embodiments, a conductive adhesive is provided between the abutting portion and the exposed solder strip portion, so that at least a portion of the abutting portion abuts against the exposed solder strip portion through the conductive adhesive.

[0012] In some embodiments, the battery string has a plurality of exposed solder ribbons spaced apart along the length of the busbar, and the busbar is provided with a plurality of abutting portions corresponding to the plurality of exposed solder ribbons in the battery string, with each exposed solder ribbon abutting against a corresponding abutting portion.

[0013] In some embodiments, a plurality of battery strings are arranged along the length of the busbar, and the plurality of battery strings are connected in series through the busbar.

[0014] In some embodiments, the insulating layer includes a coating layer disposed on the battery string, the coating layer covering the back side of the battery cell and the solder strip, the coating layer having openings that form the clearance area.

[0015] In some embodiments, the insulating layer further includes an insulating spacer layer disposed between the coating layer and the busbar, the insulating spacer layer having a clearance structure communicating with the opening.

[0016] In some embodiments, the insulating spacer is provided in the form of a strip extending along the length direction of the busbar, and the insulating spacer is provided with a clearance hole corresponding to the opening, the clearance hole forming the clearance structure, the abutting portion extending into the clearance hole, and the abutting portion abutting against the inner wall of the clearance hole in the length direction of the busbar.

[0017] In some embodiments, the insulating spacer layer includes a plurality of insulator layers spaced apart along the length direction of the busbar, the opening is located between two adjacent insulator layers to form the clearance structure between the two adjacent insulator layers, the abutment extends between two adjacent insulator layers, and the abutment abuts against the two adjacent insulator layers in the length direction of the busbar.

[0018] The technical solutions provided in this disclosure have at least the following advantages:

[0019] The busbars of a photovoltaic module are hidden on the back of the solar cells, so they do not occupy the front area of ​​the module. This maximizes the area of ​​the solar cells that can be laid, increasing the light-receiving area on the front of the module and thus improving the maximum output power of the module. At the same time, by changing the shape of the busbars to form abutment parts, the abutment parts of the busbars abut against the exposed parts of the solder ribbons. In this way, the busbars and solder ribbons are welded together through the abutment parts and the exposed parts of the solder ribbons. This not only reduces the displacement of the busbars caused by sudden localized stress during the welding process, but also allows the busbars to make better contact with the solder ribbons. This effectively reduces the risk of microcracks and fragmentation of the solar cells during subsequent lamination, and reduces the possibility of poor soldering between the busbars and the solder ribbons. Attached Figure Description

[0020] One or more embodiments are illustrated by way of example with corresponding pictures in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Unless otherwise stated, the pictures in the accompanying drawings do not constitute a limitation on scale. In order to more clearly illustrate the technical solutions in the embodiments of this disclosure or the conventional technology, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the structure of a back-contact battery assembly in the prior art.

[0022] Figure 2 This is a schematic diagram of the structure of a photovoltaic module provided in one embodiment of the present disclosure;

[0023] Figure 3 for Figure 2 A cross-sectional view of a photovoltaic module;

[0024] Figure 4 for Figure 3 A magnified view of a section at point A in the middle;

[0025] Figure 5 for Figure 2 A schematic diagram of the structure of a photovoltaic module after the busbars have been removed;

[0026] Figure 6 for Figure 2 A schematic diagram of the structure of a photovoltaic module after removing the busbars and insulating spacer layer;

[0027] Figure 7 This is a schematic diagram of the structure of another photovoltaic module provided in an embodiment of the present disclosure;

[0028] Figure 8 for Figure 7 A schematic diagram of the structure of a photovoltaic module after the busbars have been removed;

[0029] Figure 9 A schematic diagram of an opening in a photovoltaic module provided in another embodiment of the present disclosure;

[0030] Figure 10 This is a cross-sectional view of an abutting portion in another photovoltaic module provided in an embodiment of the present disclosure. Detailed Implementation

[0031] As can be seen from the background technology, reference Figure 1In the existing back-contact battery module 1000A, the front side of the back-contact battery module 1000A still has visible head and tail busbars 100A and middle busbar 200A. Thus, with the size of the back-contact battery module 1000A fixed, the head and tail busbars 100A and middle busbar 200A occupy part of the front area of ​​the back-contact battery module 1000A, thereby reducing the laying area of ​​the battery cells 300A and severely limiting the maximum output power of the back-contact battery module 1000A.

[0032] This disclosure provides a photovoltaic module in which the busbars are hidden on the back of the solar cells, thus not occupying the front area of ​​the photovoltaic module. This maximizes the area of ​​the solar cells and the illumination area on the front of the photovoltaic module, thereby increasing the maximum output power of the photovoltaic module. Simultaneously, by changing the shape of the busbars to form an abutment portion, the abutment portion of the busbar abuts against the exposed portion of the solder ribbon. In this way, the busbar and solder ribbon are welded through the abutment portion and the exposed portion of the solder ribbon. This not only reduces the displacement of the busbar due to sudden localized stress during welding, but also allows for better contact between the busbar and the solder ribbon, effectively reducing the risk of microcracks and fragmentation of the solar cells during subsequent lamination, and reducing the possibility of poor soldering between the busbar and the solder ribbon.

[0033] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined. Similarly, "multiple sets" refers to two or more sets (including two sets), and "multiple pieces" refers to two or more pieces (including two pieces).

[0034] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0035] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent three cases: A exists, A and B exist simultaneously, and B exists. In addition, the character " / " in this document generally indicates that the related objects before and after it have an "or" relationship.

[0036] In the description of the embodiments of this application, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application. For example, if the device or element in the illustration is inverted, then the element described as "below," "under," "below," or "bottom" of other elements or features will be oriented "above" or "top" of said other elements or features. Therefore, the term "below" may cover both above and below orientation depending on the context in which the term is used, which will be obvious to those skilled in the art. Materials may be oriented in other ways (e.g., rotated 90 degrees, inverted, flipped), and the spatial relative descriptive terms used herein may be interpreted accordingly.

[0037] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0038] In the accompanying drawings corresponding to the embodiments of this application, the thickness and area of ​​the layers are enlarged for better understanding and ease of description. Furthermore, when describing a component as "generally" formed on another component, it means that the component is not formed on the entire surface (or front surface) of the other component, nor is it formed on a portion of the edge of the entire surface.

[0039] In the description of the embodiments of this application, when a component "includes" another component, other components are not excluded unless otherwise stated, and other components may be further included. The formation or provision of a second component above or on a first component, or on the surface of a first component, or on one side of a first component, may include embodiments where the first and second components are in direct contact, and may also include embodiments where an additional component may be present between the first and second components, thereby preventing direct contact between the first and second components. For simplicity and clarity, various components may be drawn at different scales. In the drawings, some layers / components may be omitted for simplicity. Unless otherwise specified, the formation or provision of a second component on the surface of a first component refers to direct contact between the first and second components. The term "component" may refer to a layer, film, region, portion, structure, etc.

[0040] The terminology used in the description of the various embodiments herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used in the description of the various embodiments and the appended claims, the term "component" is also intended to include the plural form unless the context clearly indicates otherwise. Components include layers, films, regions, or plates, etc.

[0041] The embodiments of this disclosure will now be described in detail with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details have been provided in the embodiments of this disclosure to facilitate a better understanding of the disclosure. However, the technical solutions claimed in this disclosure can be implemented even without these technical details and various variations and modifications based on the following embodiments.

[0042] Figures 2 to 9 The diagram shows the structure of various photovoltaic modules provided in the embodiments of this disclosure.

[0043] refer to Figures 2 to 4 The photovoltaic module 1000 includes a cell string 100, an insulating layer 300, and a busbar 400. The cell string 100 includes multiple cells 110, and each cell 110 has a solder ribbon 200 on its back side to connect multiple cells 110 in series. The insulating layer 300 is located on the side of the solder ribbon 200 away from the cell 110, and the insulating layer 300 has a clearance area 310 to expose a portion of the solder ribbon 200 from the clearance area 310 to form a solder ribbon exposure portion 210. The busbar 400 is located on the side of the insulating layer 300 away from the solder ribbon 200, and the busbar 400 has a protruding abutment portion 410 facing the solder ribbon exposure portion 210. The abutment portion 410 abuts against the solder ribbon exposure portion 210 to electrically connect the busbar 400 and the solder ribbon 200.

[0044] Specifically, the photovoltaic module 1000 is a back-contact solar module, comprising multiple series-connected cell strings 100, each cell string 100 comprising multiple series-connected solar cells 110. The solar cells 110 are typically sheet-like structures, having a front (or light-absorbing) side and a back side opposite each other in the thickness direction. The front side of the solar cell 110 absorbs light energy and converts it into electrical energy. The back side of the solar cell 110 is provided with a first grid line and a second grid line, one of which is a positive grid line and the other a negative grid line. Each battery cell 110 has multiple solder ribbons 200 on its back side. The solder ribbons 200 extend along the length of the battery string 100 (i.e., the arrangement direction of the multiple battery cells 110 in the battery string 100). The multiple solder ribbons 200 include multiple first solder ribbons 200a and multiple second solder ribbons 200b, which are alternately arranged on the back side of the battery cell 110 along the width direction of the battery string 100. The first solder ribbons 200a are electrically connected to the first grid line, and the second solder ribbons 200b are electrically connected to the second grid line. In this way, the current of the first grid line can be conducted through the first solder ribbons 200a, and the current of the second grid line can also be conducted through the second solder ribbons 200b. The multiple battery cells 110 in the battery string 100 are connected in series through the first solder ribbons 200a and the second solder ribbons 200b.

[0045] An insulating layer 300 is disposed on the side of the solder ribbon 200 away from the cell 110. The insulating layer 300 is provided with a clearance area 310. The portion of the solder ribbon 200 and the clearance area 310 opposite each other in the thickness direction of the cell 110 is the exposed portion 210 of the solder ribbon. The clearance area 310 exposes the exposed portion 210 of the solder ribbon 200, that is, the exposed portion 210 of the solder ribbon is not covered by the insulating layer 300, while the portion of the solder ribbon 200 other than the exposed portion 210 is covered by the insulating layer 300. Busbar 400 is disposed on the side of insulating layer 300 away from solder ribbon 200. By changing the shape of the portion of busbar 400 opposite to solder ribbon exposure 210 in the thickness direction of cell 110, an abutment portion 410 is formed on busbar 400 corresponding to solder ribbon exposure 210. The abutment portion 410 and solder ribbon exposure 210 are opposite to each other in the thickness direction of cell 110. At least a portion of the abutment portion 410 extends into the clearance area 310 of insulating layer 300 and abuts against solder ribbon exposure 210, so that busbar 400 and solder ribbon 200 can be welded to solder ribbon exposure 210 through abutment portion 410.

[0046] The busbar 400 is electrically connected to the solder strip 200, specifically by the busbar 400 being electrically connected to one of the first solder strip 200a and the second solder strip 200b. For example, refer to... Figures 2 to 4In some embodiments, the insulating layer 300 has a clearance area 310 corresponding to the first solder strip 200a, the first solder strip 200a forms a solder strip exposure portion 210, and the busbar 400 is electrically connected to the first solder strip 200a through the contact portion 410 and the solder strip exposure portion 210. In other embodiments, the insulating layer 300 has a clearance area 310 corresponding to the second solder strip 200b, the second solder strip 200b forms a solder strip exposure portion 210, and the busbar 400 is electrically connected to the second solder strip 200b through the contact portion 410 and the solder strip exposure portion 210. The following description will use the example of the busbar 400 and the first solder strip 200a being electrically connected to the solder strip exposure portion 210 through the contact portion 410.

[0047] The busbar 400 of the photovoltaic module 1000 is hidden behind the solar cells 110, and the busbar 400 does not occupy the area on the front of the photovoltaic module 1000. This maximizes the area of ​​the solar cells 110 and the illumination area on the front of the photovoltaic module 1000, thereby increasing the maximum output power of the photovoltaic module 1000. At the same time, by changing the shape of the busbar 400, an abutment portion 410 is formed on the busbar 400, allowing the abutment portion 410 of the busbar 400 to... The exposed portion 210 of the solder ribbon 200 abuts against the solder ribbon 200, so that the busbar 400 and the solder ribbon 200 are welded through the abutting portion 410 and the exposed portion 210 of the solder ribbon. This not only reduces the displacement of the busbar 400 caused by sudden local stress during the welding process, but also allows the busbar 400 to make better contact with the solder ribbon 200, thereby effectively reducing the risk of microcracks and fragmentation of the battery cell 110 in the subsequent lamination process, and reducing the possibility of poor welding between the busbar 400 and the solder ribbon 200.

[0048] The embodiments of this disclosure will now be described in more detail with reference to the accompanying drawings.

[0049] The abutment portion 410 is formed on the busbar 400 by changing its shape. There are various ways to form the abutment portion 410. For example, the portion of the busbar 400 opposite to the exposed solder strip 210 is thickened to form an abutment boss (i.e., the thickened portion) on the surface of the busbar 400 near the exposed solder strip 210. This abutment boss is the abutment portion 410. Alternatively, the portion of the busbar 400 opposite to the exposed solder strip 210 is bent and deformed. This bent and deformed portion is the abutment portion 410.

[0050] refer to Figures 2 to 4 In some embodiments, a portion of the busbar 400 is recessed relative to the portion adjacent to it toward the exposed solder strip 210, and the recessed portion of the busbar 400 forms an abutment portion 410.

[0051] Specifically, the portion of the busbar 400 opposite to the exposed solder strip 210 is recessed towards the exposed solder strip 210, and the recessed portion of the busbar 400 extends into the clearance area 310 of the insulating layer 300 and abuts against the exposed solder strip 210, thus forming an abutment portion 410. This abutment portion 410 can be formed by stamping an existing busbar 400, causing a partial recess to form the abutment portion 410. This method of forming a busbar 400 with such a special shape results in relatively low processing costs.

[0052] The specific shape of the recessed abutment portion 410 is not particularly limited; the abutment portion 410 can be square, trapezoidal, or arc-shaped, etc. (See reference) Figures 2 to 4 In some embodiments, the abutment portion 410 is arc-shaped. The arc-shaped abutment portion 410 is relatively easy to manufacture and can also avoid stress concentration at the abutment portion 410.

[0053] The width of the abutment portion 410 is its dimension in the width direction of the busbar 400. The width of the abutment portion 410 may be less than or equal to the width of the busbar 400. (Reference) Figures 2 to 4 In some embodiments, the dimension of the abutment portion 410 in the width direction of the busbar 400 is equal to the width of the busbar 400. Making the abutment portion 410 as wide as possible not only reduces the processing difficulty of the abutment portion 410, but also helps to increase the effective conductive area between the abutment portion 410 and the exposed solder strip portion 210.

[0054] In other embodiments, conductive adhesive is provided between the abutment portion 410 and the exposed solder strip portion 210, so that at least a portion of the abutment portion 410 abuts against the exposed solder strip portion 210 through the conductive adhesive. Filling the space between the abutment portion 410 and the exposed solder strip portion 210 with conductive adhesive helps to increase the effective conductive area between the abutment portion 410 and the exposed solder strip portion 210, and reduces the possibility of poor soldering between the abutment portion 410 and the exposed solder strip portion 210.

[0055] refer to Figure 2 , Figure 5 and Figure 6 The battery string 100 typically has multiple first solder strips 200a along its width, and these multiple first solder strips 200a are electrically connected via a busbar 400. For example, see reference... Figure 2 , Figure 5 and Figure 6In some embodiments, the battery string 100 has multiple exposed solder ribbons 210 spaced apart along the length of the busbar 400. The busbar 400 has multiple abutment portions 410 corresponding to the multiple exposed solder ribbons 210 in the battery string 100, with each exposed solder ribbon 210 abutting against a corresponding abutment portion 410. The insulating layer 300 has multiple clearance areas 310 spaced apart along the length of the busbar 400, allowing the battery string 100 to form multiple exposed solder ribbons 210 spaced apart along the length of the busbar 400. The length of the busbar 400 is perpendicular or approximately perpendicular to the length of the solder ribbons 200. This arrangement allows for more diverse placement of the battery cells 110, which is beneficial for increasing the placement area of ​​the battery cells.

[0056] refer to Figure 2 , Figure 5 and Figure 6 A photovoltaic module 1000 typically includes multiple cell strings 100, which are connected in series via a busbar 400. For example, see reference... Figure 2 , Figure 5 and Figure 6 In some embodiments, multiple battery strings 100 are arranged along the length of the busbar 400, and the multiple battery strings 100 are connected in series through the busbar 400. This arrangement allows for more diverse ways of laying the battery cells 110, which is beneficial for increasing the laying area of ​​the battery cells.

[0057] An insulating layer 300 is provided between the busbar 400 and the solder ribbon 200. The insulating layer 300 can insulate the busbar 400 from the second solder ribbon 200b and the second grid line of the battery cell 110. Since the insulating layer 300 has a clearance area 310 corresponding to the exposed portion 210 of the first solder ribbon 200a, the abutting portion 410 of the busbar 400 can extend into the clearance area 310 and abut against the exposed portion 210 of the first solder ribbon 200a, thereby making the busbar 400 and the first solder ribbon 200a electrically connected.

[0058] There are various ways to specifically install the insulating layer 300; for example, the insulating layer 300 can be insulating adhesive, insulating tape, or insulating film, etc. (See reference) Figure 2 , Figure 5 and Figure 6 In some embodiments, the insulating layer 300 includes a coating layer 320 disposed on the battery string 100, the coating layer 320 covering the back of the battery cell 110 and the solder strip 200, and the coating layer 320 having an opening 321 forming a clearance area 310.

[0059] Specifically, the coating layer 320 is an insulating film, and the coating layer 320 is provided with multiple openings 321, which respectively form multiple clearance areas 310. The specific shape of the openings 321 is not particularly limited, and the openings 321 can be square, circular, or diamond-shaped, etc. For example, see reference. Figure 5 and Figure 6 In some embodiments, the opening 321 is a square hole.

[0060] The coating layer 320 can be applied to the back of the solar cell 110 using a low-temperature coating technique. For example, a coating layer 320 is first laid down and perforated; after positioning, solder ribbons 200 are placed on the coating layer 320; then the solar cell 110 is placed; finally, heating and pressurizing are applied to fix the solder ribbons 200 to the solar cell 110 by the coating layer 320. Using a low-temperature coating technique to apply the coating layer 320 to the back of the solar cell 110 can reduce warping of the solar cell 110, and the coating layer 320 can protect most of the grid area of ​​the solar cell 110, thus preventing short circuits caused by solder splatter during the soldering of the busbar 400. The specific material of the coating layer 320 can be set according to the actual situation. For example, the coating layer 320 can be an EVA (ethylene-vinyl acetate copolymer) film, a POE (polyethylene octene coelastomer) film, an EP film (two-layer co-extruded film of EVA and POE) or an EPE film (three-layer co-extruded film of EVA and POE), etc.

[0061] The coating layer 320 covers the back side of each battery cell 110 in the battery string 100, and there are various specific arrangements for the coating layer 320. For example, see reference... Figure 6 In some embodiments, the coating layer 320 includes multiple coating sub-layers 322, which are arranged in a one-to-one correspondence with multiple battery cells 110 in the battery string 100. Each coating sub-layer 322 covers the back side of a corresponding battery cell 110. The shape and size of the coating sub-layers 322 are adapted to the shape and size of the battery cells 110. The multiple coating sub-layers 322 are respectively covered on the back side of the multiple battery cells 110 in the battery string 100. The multiple coating sub-layers 322 are not connected into a whole. In this way, the coating layer 320 is formed by multiple sheet-like coating sub-layers 322, which can reduce the setting area of ​​the coating layer 320 and reduce the amount of coating layer 320 used.

[0062] For example, in other embodiments, the coating layer 320 extends along the length of the battery string 100, and the dimension 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. This not only helps to ensure 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 solder ribbon 200 connecting two adjacent battery cells 110 to be completely covered by the coating layer 320.

[0063] refer to Figures 2 to 4 In some embodiments, the insulating layer 300 further includes an insulating spacer layer 330, which is disposed between the coating layer 320 and the busbar 400. The insulating spacer layer 330 is provided with a clearance structure 331 communicating with the opening 321.

[0064] Specifically, an insulating spacer layer 330 is provided between the coating layer 320 and the busbar 400. Thus, the thickness of the insulating layer 300 at the junction of the busbar 400 and the solder strip 200 is the sum of the thickness of the coating layer 320 and the thickness of the insulating spacer layer 330. This ensures that the insulating layer 300 has sufficient thickness at the junction of the busbar 400 and the solder strip 200, thereby ensuring the insulating effect of the insulating layer 300. The insulating spacer layer 330 can be insulating adhesive, insulating tape, or insulating film, etc.

[0065] The thermoplasticity of the coating layer 320 is generally better than that of the insulating spacer layer 330. This not only ensures that the coating layer 320 has a better coating effect, but also helps to ensure that the insulating layer 300 has sufficient thickness at the connection between the busbar 400 and the solder strip 200 through the setting of the insulating spacer layer 330. The specific material of the insulating spacer layer 330 can be set according to the actual situation. For example, the insulating spacer layer 330 can be a PET (polyethylene terephthalate) film or a PI (polyimide) film.

[0066] The insulating spacer 330 ensures that the insulating layer 300 has sufficient thickness at the connection between the busbar 400 and the solder strip 200, and the specific thickness of the insulating spacer 330 can be set according to the actual situation. In some embodiments, the thickness of the insulating spacer 330 is 0.03 to 0.2 mm.

[0067] 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. By optimizing the thickness range of the insulating spacer 330, it is possible to ensure that the insulating layer 300 has sufficient thickness at the connection between the busbar 400 and the welding strip 200. This avoids the situation where the insulating spacer 330 is too thin, making it inconvenient to apply, easy to be deformed by pulling, and risking damage to the insulation over a long period of time. It also avoids the situation where the insulating spacer 330 is too thick, resulting in a large height difference between the busbar 400 and the welding strip 200, which could cause microcracks and fragmentation of the battery cell 110 during subsequent lamination.

[0068] An insulating spacer 330 is disposed between the coating layer 320 and the busbar 400. The insulating spacer 330 is generally arranged along the length of the busbar 400, and the dimension of the insulating spacer 330 in the width direction of the busbar 400 is greater than or equal to the width of the busbar 400.

[0069] refer to Figure 2 and Figure 5 In some embodiments, the insulating spacer layer 330 includes a plurality of insulator layers 332 spaced apart along the length of the busbar 400, and an opening 321 is located between two adjacent insulator layers 332 to form a clearance structure 331 between two adjacent insulator layers 332.

[0070] Specifically, a single insulator layer 332 is arranged in a block shape, and multiple insulator layers 332 are arranged at intervals along the length of the busbar 400 to form an insulating spacer layer 330. Furthermore, the multiple insulator layers 332 and the multiple openings 321 of the coating layer 320 are arranged alternately along the length of the busbar 400. The gap between the two insulator layers 332 on both sides of each opening 321 forms a clearance structure 331, thereby ensuring that the insulating spacer layer 330 forms multiple clearance structures 331 corresponding to the multiple openings 321 of the coating layer 320. The distance between two adjacent insulator layers 332 is greater than or equal to the size of the opening 321 along the length of the busbar 400. By forming the insulating spacer layer 330 with multiple insulator layers 332, the area and quantity of the insulating spacer layer 330 can be reduced.

[0071] The number of insulator layers 332 can be less than the number of openings 321; the number of insulator layers 332 can also be equal to the number of openings 321; the number of insulator layers 332 can also be greater than the number of openings 321. (Reference) Figure 2 and Figure 5 In some embodiments, multiple openings 321 are provided at intervals along the length direction of the busbar 400, and each opening 321 is provided with an insulator layer 332 on both sides of the busbar 400 along the length direction.

[0072] Specifically, the number of insulator layers 332 is greater than the number of openings 321, so that two insulator layers 332 can be distributed on both sides of each opening 321. In this way, the insulator layers 332 are provided on both sides of each opening 321, which can reduce the gap between the busbar 400 and the coating layer 320, so that the contact position between the busbar 400 and the welding strip 200 can be relatively flat.

[0073] refer to Figure 10 In some embodiments, the abutment portion 410 extends between two adjacent insulator layers 332, and the abutment portion 410 abuts against the two adjacent insulator layers 332 in the length direction of the busbar 400.

[0074] Specifically, the dimension of the abutment portion 410 in the length direction of the busbar 400 is the length of the abutment portion 410. The length of the longest part of the abutment portion 410 is equal to or approximately equal to the distance between two adjacent insulator layers 332, so that the abutment portion 410 can abut against the two adjacent insulator layers 332 in the length direction of the busbar 400. This can reduce the displacement of the busbar 400 in the length direction caused by sudden local stress.

[0075] refer to Figure 7 and Figure 8 In 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 a clearance hole 331a corresponding to the opening 321, the clearance hole 331a forming a clearance 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 elongated. 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 multiple clearance holes 331a corresponding to the multiple openings 321 of the coating layer 320, and each clearance hole 331a communicates with a corresponding opening 321. The size of the clearance hole 331a may be greater than or equal to the size of the opening 321, and the shape of the clearance hole 331a is usually adapted to the shape of the opening 321. For example, refer to Figure 7 and Figure 8 In some embodiments, both the clearance hole 331a and the opening 321 are square holes. By making the insulating spacer layer 330 into a long strip shape, gaps can be avoided between the busbar 400 and the coating layer 320, so that the contact position between the busbar 400 and the solder strip 200 can be relatively flat.

[0077] refer to Figure 10 In some embodiments, the abutment portion 410 extends into the clearance hole 331a, and the abutment portion 410 abuts against the inner wall of the clearance hole 331a in the length direction of the busbar 400.

[0078] Specifically, the dimension of the clearance hole 331a in the width direction of the solder strip 200 (i.e., the length direction of the busbar 400) is equal to the width of the clearance hole 331a. The length of the longest part of the abutment portion 410 is equal to or approximately equal to the width of the clearance hole 331a, so that the abutment portion 410 can abut against the two inner walls of the clearance hole 331a opposite each other in the length direction of the busbar 400. This can reduce the displacement of the busbar 400 in the length direction caused by sudden local stress.

[0079] In other embodiments, the abutment portion 410 extends into the clearance hole 331a, and the abutment portion 410 abuts against the inner wall of the clearance hole 331a in the width direction of the busbar 400.

[0080] Specifically, the dimension of the clearance hole 331a in the length direction of the solder strip 200 (i.e., the width direction of the busbar 400) is the length of the clearance hole 331a. The width of the widest part of the abutment portion 410 is equal to or approximately equal to the length of the clearance hole 331a, so that the abutment portion 410 can abut against the two inner walls of the clearance hole 331a opposite each other in the width direction of the busbar 400. This can reduce the displacement of the busbar 400 in the width direction caused by sudden localized force.

[0081] The thickness of the solder strip 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 solder strip 200 can be less than the thickness of the coating layer 320; the thickness of the solder strip 200 can also be equal to the thickness of the coating layer 320; the thickness of the solder strip 200 can also be greater than the thickness of the coating layer 320. (Reference) Figure 4 In some embodiments, the surface of the exposed ribbon 210 away from the cell 110 is located on the side of the coating layer 320 near the insulating spacer layer 330, and the surface of the insulating spacer layer 330 near the busbar 400 is located on the side of the exposed ribbon 210 away from the cell 110.

[0082] Specifically, the thickness of the solder ribbon 200 can be less than the thickness of the coating layer 320, so that the surface of the solder ribbon exposure 210 away from the cell 110 is located on the side of the coating layer 320 near the insulating spacer layer 330, that is, the solder ribbon exposure 210 extends towards the busbar 400 out of the opening 321 of the coating layer 320. The thickness of the solder 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 near the busbar 400 is located on the side of the solder ribbon exposure 210 away from the cell 110, that is, the portion of the solder ribbon exposure 210 extending out of the opening 321 is located within the clearance structure 331 of the insulating spacer layer 330.

[0083] refer to Figure 9 The back of the solar cell 110 is typically provided with insulating adhesive 120, which can insulate the first grid line and the second grid line of the solar cell 110. Since the back of the solar cell 110 is provided with a coating layer 320, the coating layer 320 can protect most of the grid line area of ​​the solar cell 110, thus reducing the amount of insulating adhesive 120 used.

[0084] refer to Figure 9 In some embodiments, an insulating adhesive 120 is provided between the solder ribbon 200 and the back side of the battery cell 110. The dimension of the insulating adhesive 120 in the width direction of the solder ribbon 200 is greater than or equal to the dimension of the opening 321 in the width direction of the solder ribbon 200, so that the projection of the opening 321 on the back side of the battery cell 110 is located on the insulating adhesive 120.

[0085] Specifically, the dimension of the insulating adhesive 120 in the width direction of the solder ribbon 200 is the width of the insulating adhesive 120, and the dimension of the opening 321 in the width direction of the solder ribbon 200 is the width of the opening 321. The width of the opening 321 is greater than the width of the solder ribbon 200, and the width of the insulating adhesive 120 is greater than or equal to the width of the opening 321. This ensures that the portion of the back side of the battery cell 110 exposed from the opening 321, excluding the exposed portion 210 of the solder ribbon, is entirely covered by the insulating adhesive 120 and the coating layer 320. With the opening of the coating layer 320 exposing the exposed portion 210 of the solder ribbon, as long as the opening position of the coating layer 320 is properly set, the insulating adhesive 120 and the coating layer 320 will protect the busbar 400 after soldering failure, preventing foreign objects from contacting the grid lines of the battery cell 110 and causing a short circuit.

[0086] Those skilled in the art will understand that the above embodiments are specific examples of implementing this disclosure, and in practical applications, various changes in form and detail may be made without departing from the spirit and scope of this disclosure. Any person skilled in the art can make various alterations and modifications without departing from the spirit and scope of this disclosure; therefore, the scope of protection of this disclosure should be determined by the scope defined in the claims.

Claims

1. A photovoltaic module, characterized in that, include: A battery string, comprising multiple battery cells, each battery cell having a solder strip on its back side to connect multiple battery cells in series via the solder strip; An insulating layer is disposed on the side of the solder ribbon away from the battery cell, and the insulating layer is provided with a clearance area so that a portion of the solder ribbon is exposed from the clearance area to form a solder ribbon exposure portion; A busbar is disposed on the side of the insulating layer away from the solder strip. The busbar has a protruding abutment portion facing the exposed portion of the solder strip, and the abutment portion abuts against the exposed portion of the solder strip to electrically connect the busbar to the solder strip.

2. The photovoltaic module according to claim 1, characterized in that, A portion of the busbar is recessed relative to the adjacent portion toward the exposed weld strip, and the recessed portion of the busbar forms the abutment portion.

3. The photovoltaic module according to claim 2, characterized in that, The abutment portion is arc-shaped.

4. The photovoltaic module according to claim 2, characterized in that, The dimension of the abutment portion in the width direction of the busbar is equal to the width of the busbar.

5. The photovoltaic module according to claim 1, characterized in that, A conductive adhesive is provided between the abutting portion and the exposed solder strip portion, so that at least a portion of the abutting portion abuts against the exposed solder strip portion through the conductive adhesive.

6. The photovoltaic module according to claim 1, characterized in that, The battery string has a plurality of exposed solder strips spaced apart along the length of the busbar. The busbar is provided with a plurality of abutting parts corresponding to the plurality of exposed solder strips in the battery string, and each exposed solder strip abuts against a corresponding abutting part.

7. The photovoltaic module according to claim 1, characterized in that, Multiple battery strings are arranged along the length of the busbar, and the multiple battery strings are connected in series through the busbar.

8. The photovoltaic module according to claim 1, characterized in that, The insulating layer includes a coating layer disposed on the battery string, the coating layer covering the back of the battery cell and the solder strip, and the coating layer having openings that form the clearance area.

9. The photovoltaic module according to claim 8, characterized in that, The insulating layer further includes an insulating spacer layer disposed between the coating layer and the busbar, and the insulating spacer layer is provided with a clearance structure communicating with the opening.

10. The photovoltaic module according to claim 9, characterized in that, The insulating spacer layer is arranged in the shape of a strip extending along the length direction of the busbar. The insulating spacer layer is provided with a clearance hole corresponding to the opening. The clearance hole forms the clearance structure. The abutting part extends into the clearance hole and abuts against the inner wall of the clearance hole in the length direction of the busbar. or, The insulating spacer layer includes a plurality of insulator layers spaced apart along the length of the busbar. The opening is located between two adjacent insulator layers to form the clearance structure between the two adjacent insulator layers. The abutting portion extends between two adjacent insulator layers and abuts against the two adjacent insulator layers in the length of the busbar.

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