Photovoltaic module with hidden bus bar

Abstract

A photovoltaic module with a hidden bus bar is provided and comprises battery strings, the battery strings are a plurality of battery pieces connected in series in the X direction, and the plurality of battery strings are arranged in the Y direction; the battery pieces comprise positive electrode grid lines and negative electrode grid lines which are alternately arranged and are connected through positive electrode welding strips and negative electrode welding strips, and the battery pieces in the battery strings are connected through the positive electrode welding strips or the negative electrode welding strips; the bus bars are arranged along the Y direction and are connected with two adjacent battery strings; the bus bar comprises a bus bar main body and a plurality of extension parts which are arranged at intervals along the extension direction of the bus bar main body and are perpendicular to the main body, the extension parts are positioned on one side or two sides of the bus bar main body, and one ends of the extension parts extend out of the bus bar main body and are arranged above the first welding strip to be welded with the first welding strip; the insulating layer is arranged below the bus bar and is arranged on the second welding strip below the bus bar; wherein the first welding strip is a welding strip which is directly connected and welded with the bus bar, and the second welding strip is a welding strip which is not directly connected and welded with the bus bar. The photovoltaic module provided by the utility model does not have a sealing-off problem.

Description

Technical Field

[0001] The present application relates to a photovoltaic module with hidden busbars, belonging to the technical field of photovoltaic modules. Background Art

[0002] In the prior art, a photovoltaic cell module is formed by string welding or full-panel welding of multiple back-contact cells, lamination, and packaging. A photovoltaic cell module includes multiple cell strings, with busbars connecting two cell strings. The busbars of the prior art are placed in the gap between the cell strings, or in the gap on one side of the cell string. Figure 1 Schematic diagram of a photovoltaic module in the prior art; due to the presence of the gap area, the busbars can also be seen from the front of the photovoltaic module, affecting the appearance; moreover, the presence of the gap area also occupies the space of the photovoltaic module and squeezes the area of ​​the battery cell. Utility Model Content

[0003] The present application aims to solve at least one of the problems of the prior art and provide a photovoltaic assembly with hidden bus bars. The photovoltaic assembly with hidden bus bars provided by the present application does not have the problem of desoldering.

[0004] A photovoltaic module with hidden busbars is provided, comprising a battery string, wherein the battery string comprises a plurality of battery cells connected in series along an X direction, and the plurality of battery strings are arranged along a Y direction on the photovoltaic module;

[0005] The battery cell includes alternating positive and negative grid lines on the back side. The positive grid lines are connected by positive welding strips, and the negative grid lines are connected by negative welding strips. Two adjacent battery cells in a battery string are connected by positive welding strips or by negative welding strips.

[0006] The battery further includes a bus bar, which is arranged along the Y direction and connects two adjacent battery strings. The bus bar includes a bus bar body and a plurality of extensions arranged at intervals along the extension direction of the bus bar body. The extension direction of the extension is perpendicular to the extension direction of the bus bar body. The extension is located on one side or both sides of the bus bar body and is arranged above the first welding strip and welded to the first welding strip.

[0007] The busbar further comprises an insulating layer disposed below the busbar, wherein the width of the insulating layer is not less than the width of the busbar body, and the insulating layer is disposed at least on the second welding strip located below the busbar to insulate the busbar from the second welding strip;

[0008] The first welding strip is a welding strip covered by the bus bar and directly connected and welded to the bus bar, and the second welding strip is a welding strip covered by the bus bar and not directly connected and welded to the bus bar;

[0009] When the extension portion is located on one side of the busbar body, one end of the extension portion extends out of the busbar body, and adjacent extension portions extend out of the busbar body in the same direction;

[0010] Among them, when the extension part is located on both sides of the busbar body, one end of the extension part extends out of the busbar body, and the adjacent extension parts extend out of the busbar body in opposite directions; or, both ends of the extension part extend out of the busbar body, and the adjacent extension parts extend out of the same side of the busbar body to different lengths.

[0011] In some embodiments of a photovoltaic assembly with a hidden busbar, the extension portion and the busbar body are integrally formed, or the extension portion is fixedly disposed above or below the busbar body.

[0012] In some embodiments, a photovoltaic assembly with a hidden busbar has a width of 3 mm to 20 mm.

[0013] And / or, the length of the extension portion extending from the busbar body is 1 mm to 60 mm.

[0014] In some embodiments of a photovoltaic assembly with hidden busbars, the width of the extension portion is 0.1 mm to 4 mm; or the width of the extension portion is 0.5 to 4 times the width of the electrical connection ribbon.

[0015] In some embodiments of a photovoltaic module with hidden busbars, the insulating layer is an insulating strip, and its extension direction is the same as the extension direction of the busbar body;

[0016] Alternatively, the insulating layer is an intermittently arranged insulating strip, which covers the corresponding position of the second welding strip covered by the bus bar and is disconnected at the corresponding position of the first welding strip covered by the bus bar;

[0017] Alternatively, the insulating layer includes an insulating strip body and protrusions protruding along the width direction and spaced apart in the length direction of the insulating strip body. The extension direction of the insulating strip body is the same as the extension direction of the bus bar body. The protrusions are arranged corresponding to the extension portion of the bus bar and do not exceed the extension portion.

[0018] In some embodiments, a photovoltaic module with hidden busbars includes three groups of busbars, which are respectively arranged on both sides of the photovoltaic module in the X direction and on a row of solar cells in the middle, namely edge busbars and middle busbars.

[0019] In some embodiments, a photovoltaic module with hidden bus bars comprises a plurality of edge bus bars, wherein the edge bus bars are connected to the same-sex welding strips of a battery cell, or to the opposite-sex welding strips of two adjacent battery cells in the Y direction, and are disconnected in the middle; the middle bus bars comprise a plurality of middle bus bars, wherein the middle bus bars are connected to the same-sex welding strips of a battery cell, or to the opposite-sex welding strips of two adjacent battery cells in the Y direction, and are disconnected in the middle; the position where the middle bus bars are disconnected is staggered with the position where the edge bus bars are disconnected.

[0020] In some embodiments of a photovoltaic module with hidden busbars, the spacing between adjacent solar cells in a battery string is zero spacing or negative spacing.

[0021] In some embodiments of a photovoltaic module with hidden busbars, the cell is a busbar-less back-contact solar cell.

[0022] The photovoltaic module with hidden busbar of the present application has a busbar including a main body and an extension extending outward, and is welded to the cell grid line only through the extension corresponding to the welding strip. Compared with the method of welding the busbar main body and the welding strip, the required welding energy is low, which can effectively avoid the technical problem of desoldering of the welding strip and the cell grid line caused by the high welding energy of the busbar main body; at the same time, the adverse effect of the height difference caused by the insulating layer under the busbar main body on the welding of the busbar main body can be reduced by the extended length of the busbar extension. The overlap area of ​​the busbar extension and the welding strip can be controlled to achieve good welding of the cell grid line, the welding strip and the extension, thereby avoiding problems such as desoldering caused by high-temperature welding. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0024] Figure 1 A schematic diagram of the structure of a photovoltaic module in the prior art;

[0025] Figure 2 A schematic diagram of the arrangement of cells and ribbons of the photovoltaic module of this application;

[0026] Figure 3 A schematic diagram of the structure of a photovoltaic module with an insulating layer provided on the welded cells and welding ribbons;

[0027] Figure 4 is a schematic structural diagram of a bus bar according to an embodiment;

[0028] Figure 5 This is a schematic diagram of the structure of the photovoltaic module after busbar welding is completed;

[0029] Figure 6 A schematic structural diagram of an insulating strip according to one embodiment;

[0030] Figure 7 is a schematic structural diagram of a bus bar according to an embodiment;

[0031] Figure 8 A schematic diagram of the structure of a busbar in one embodiment

[0032] The figure includes: 10 - battery cell, 20 - welding ribbon, 21 - first welding ribbon, 22 - second welding ribbon, 30 - bus bar, 31 - edge bus bar, 32 - middle bus bar, 301 - bus bar body, 302 - extension part, 40 - insulation layer. DETAILED DESCRIPTION

[0033] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below with reference to the accompanying drawings.

[0034] In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application may also be implemented in other ways different from those described herein. Those skilled in the art may make similar generalizations without violating the connotation of the present application. Therefore, the present application is not limited to the specific embodiments disclosed below.

[0035] Secondly, this application is described in detail with reference to schematic diagrams. When describing the embodiments of this application, for ease of explanation, cross-sectional views of device structures may be partially enlarged and not to scale. Furthermore, these schematic diagrams are merely illustrative and should not limit the scope of protection of this application. Furthermore, in actual production, three-dimensional dimensions, including length, width, and depth, should be included.

[0036] In the prior art, a photovoltaic cell module is formed by string welding or full-panel welding of multiple back-contact cells, lamination, and packaging. A photovoltaic cell module includes multiple cell strings, with busbars connecting two cell strings. Figure 1 , is a structural diagram of a photovoltaic module in the prior art. The busbar is arranged in the gap area between the battery string groups, or in the gap area on one side of the battery string group. Due to the existence of the gap area, the busbar can also be seen from the front of the photovoltaic module, affecting the appearance; moreover, the existence of the gap area also occupies the space of the photovoltaic module and squeezes the area of ​​the battery cell.

[0037] An embodiment of the present application provides a back-contact cell photovoltaic module, which reduces or eliminates the gap area between cell strings, arranges the bus bar above a row of cells in the cell string group, and hides the bus bar from the front of the photovoltaic module. The module is aesthetically pleasing and can effectively utilize the position of the photovoltaic module to increase the module power.

[0038] Based on this, see Figures 2 to 8 ,in, Figure 2 The diagram shows the arrangement of cells and ribbons of photovoltaic modules. Figure 3 The figure shows the structure of the photovoltaic module with the completed soldered cells and the insulating layer set on the soldering ribbon. Figure 4 is a schematic diagram of the busbar structure. Figure 5 This is a schematic diagram of the structure of a photovoltaic module after busbar welding is completed. The embodiment of the present application provides a photovoltaic module, including multiple battery strings, see Figure 2 , Figure 2 The X direction and the Y direction are two perpendicular directions, with the X direction being the column direction and the Y direction being the row direction. The battery string is arranged along the X direction. Specifically, a plurality of battery cells 10 are arranged along the X direction and connected by welding ribbons 20 to form a battery string. A plurality of battery strings are arranged along the Y direction, such as Figure 2 As shown, six rows of battery strings are arranged along the Y direction. The battery cells described in this application are back-contact solar cell cells, and the photovoltaic modules are back-contact solar cell photovoltaic modules. Those skilled in the art are aware of the ways in which the welding ribbons of back-contact solar cell photovoltaic modules of different versions are connected to the battery cells, and the ways in which the busbars are connected to the welding ribbons. For details, reference may be made to the prior art. The main improvements of this application lie in the structure of the busbars, and the relative positions of the busbars and the battery cells. Specifically, the battery cells include alternating positive and negative grid lines of opposite sex arranged on the back side thereof. The positive grid lines are connected through the positive welding ribbons, and the negative grid lines are connected through the negative welding ribbons. The grid lines can be set on the back side of the battery cells by screen printing or other methods, and the welding ribbons are welded to the grid lines to electrically connect the battery cells, thereby guiding the current. In a string of battery cells, two adjacent battery cells are connected by the positive welding ribbons, or by the negative welding ribbons, which can be set according to the version of the photovoltaic module. The battery cells of a string of battery cells are connected to each other by the positive welding ribbons and the negative welding ribbons to form a string. Multiple battery strings can be welded into strings with single strings of battery cells and then arranged according to the photovoltaic module layout, or after all battery cells and welding ribbons are placed, the corresponding welding ribbons and battery cells are welded into strings, for example, by laser welding, electromagnetic welding or infrared welding.

[0039] The busbar 30 extends along the Y direction and is arranged on a row of battery cells 1 in the Y direction to connect adjacent battery strings. Figure 5 The busbars 30 may include three groups, which are placed on two rows of battery cells 1 at the edges in the X direction and one row in the middle, wherein the ones arranged at the edges are edge busbars 31 and the ones arranged in the middle are middle busbars 32.

[0040] The busbar 30 is electrically connected to the positive electrode welding ribbon and insulated from the negative electrode welding ribbon, or is connected to the negative electrode welding ribbon and insulated from the positive electrode welding ribbon. For ease of description, the welding ribbon covered by the busbar and electrically connected thereto is referred to as the first welding ribbon 21, and the welding ribbon covered by the busbar but not connected thereto is referred to as the second welding ribbon 22.

[0041] Continue to see Figure 4 and Figure 5 The busbar 30 is arranged above the battery cell 1, wherein, see Figure 4 The busbar 30 includes a busbar body 301 and a plurality of extensions 302 spaced apart along the extending direction of the busbar body 301; the extensions 302 are arranged perpendicular to the extending direction of the busbar body 301, and the extensions 302 are located on one side or both sides of the busbar body 301. Figure 5 The extension portion 302 is arranged in a one-to-one correspondence with the first welding strip 21 and is arranged above the first welding strip 21 and welded to the first welding strip 21 at this location.

[0042] An insulating layer 40 is provided below the bus bar 30. Figure 3 The insulating layer 40 is wider than the busbar body 301 and is at least provided on the second welding strip below the busbar in order to achieve insulation between the busbar and the second welding strip and avoid electrical leakage.

[0043] Preferably, the width of the busbar body 301 is 3-20 mm. The length of the extension portion 302 extending from the busbar body 301 is 1-60 mm, and the width of the extension portion is 0.1-4 mm, or the width of the extension portion is 0.5-4 times the width of the first welding strip.

[0044] The extension portion may be located at the upper portion of the busbar body (away from the battery cells) or at the lower portion of the busbar body (close to the battery cells).

[0045] The busbar of the present application includes a technical solution in which the busbar main body and an extension portion extend outward. The extension portion corresponding to the welding strip is welded to the welding strip. Compared with the method of welding the busbar main body to the welding strip, the required welding energy is low, which can effectively avoid the technical problem of desoldering of the welding strip and the battery cell grid line caused by the high welding energy of the busbar main body; at the same time, the length of the busbar extension portion can also be used to reduce the adverse effect of the height difference caused by the insulating layer under the busbar main body on the welding of the busbar main body. The overlap area of ​​the busbar extension portion and the welding strip can be controlled to achieve good welding of the battery cell grid line, the welding strip and the extension portion, and avoid problems such as desoldering caused by high-temperature welding.

[0046] The insulating layer 40 may be Figure 3 、 Figure 5 The intermittent insulating strip shown covers the corresponding position of the second welding strip covered by the busbar, and is disconnected at the position of the first welding strip covered by the busbar to prevent contact and leakage between the busbar and the second welding strip. It can also be a continuous insulating strip with a width slightly larger than the width of the busbar body. As a preferred embodiment, see Figure 6 It includes an insulating strip body and protrusions that are spaced apart in the length direction of the insulating strip body and protrude in the width direction. The protrusions are arranged corresponding to the extensions of the busbars to avoid current enrichment.

[0047] Those skilled in the art will understand that although the present invention uses the description of arranging insulating strips, the insulating strips can be insulating glue, which can be arranged by coating, dispensing, etc., or they can be insulating strips that can be arranged by placing them.

[0048] As a half-cell BC type battery, the edge bus bar 31 of the component includes multiple bars, wherein the edge bus bar 31 connects the same-sex welding strip of a battery cell, or connects the opposite-sex welding strips of two adjacent battery cells in the Y direction, and is disconnected in the middle. The middle bus bar 32 of the component includes multiple bars, wherein the middle bus bar 32 connects the same-sex welding strip of a battery cell, or connects the opposite-sex welding strips of two adjacent battery cells 1 in the Y direction, and is disconnected in the middle. The disconnection position of the middle bus bar 32 is staggered with the disconnection position of the edge bus bar 31. Figure 5 For example, there are three edge busbars 31, each connecting the soldering ribbons of two adjacent battery cells in the Y direction; there are four middle busbars 32, connecting the soldering ribbons of the top, middle, middle, and bottom battery cells respectively. When the number of battery cells is the same, the polarity of the edge busbars connecting the soldering ribbons is the same, and different from the polarity of the middle busbars connecting the soldering ribbons. Figure 5 , taking six columns of battery cells as an example, from top to bottom they are the first to sixth columns. The edge bus bars are respectively connected to the negative electrode welding ribbon, positive electrode welding ribbon, negative electrode welding ribbon, positive electrode welding ribbon, negative electrode welding ribbon and positive electrode welding ribbon on the first to sixth columns of battery cells; they are disconnected between the second and third columns, and between the fourth and fifth columns. The middle bus bars are respectively connected to the positive electrode welding ribbon, negative electrode welding ribbon, positive electrode welding ribbon, negative electrode welding ribbon, positive electrode welding ribbon and negative electrode welding ribbon on the first to sixth columns of battery cells; they are disconnected between the first and second columns, between the third and fourth columns, and between the fifth and sixth columns. If the component circuit is not a symmetrical half-cell configuration, the way the corresponding welding ribbons connect the battery cells varies with the design of the component circuit.

[0049] Correspondingly, the insulating layer 40 and the bus bar 30 are arranged in a one-to-one correspondence. Specifically, the insulating layer 40 is arranged below the bus bar 30 .

[0050] In one embodiment, the bus bar 30 may be integrally formed, in which case the bus bar body 301 and the extension portion 302 are integrally formed.

[0051] The busbar body 301 and the extensions 302 of the busbar 30 can also be prepared separately and then fixed together. Specifically, a long strip of busbar body 301 and a plurality of extensions 302 are prepared; a plurality of extensions 302 extending along the width direction of the busbar body 301 are placed at intervals along the extension direction of the busbar body 301, and the extensions 302 and the busbar body 301 are welded to form the required busbar 30. Figure 4Compared with one-piece molding, the busbar with a welding portion is prepared using conventional busbars and welding strips. Different busbars can be prepared according to different templates, which is more flexible.

[0052] See also Figure 4 and Figure 5 The extension portion can be located on one side of the busbar body, the extension portion extends out of the busbar body, and adjacent extension portions extend out of the busbar body in the same direction. Figure 4 , all extensions extend beyond the left side of the busbar body.

[0053] See also Figure 7 and Figure 8 , Figure 7 and Figure 8 Both are structural diagrams showing that the extensions are located on both sides of the busbar body. Figure 7 One end of the extension extends out of the busbar body, and the adjacent extensions extend out of the busbar in opposite directions, extending out of the left and right sides of the busbar body respectively. Figure 8 Both ends of each extension extend out of the busbar body, but the lengths of the extensions at both ends are different, such as Figure 8 As shown, adjacent extensions extend from the same side of the busbar body to varying lengths. When interlayer shear forces are present during processing or operation, the technical solution of having extensions on both sides of the busbar body can enhance the overall shear force tolerance of the photovoltaic module and prevent unilateral peeling of the busbar / welding ribbon.

[0054] The insulating layer can be directly affixed to the busbar. The following diagram illustrates the structure of the insulating layer affixed to the busbar. The insulating layer is a non-conductive tape or film, such as a PET or PI tape coated with acrylic or silicone, or a PET or PI substrate coated on one or both sides with ethylene-vinyl acetate copolymer or hot melt adhesive. For example, the insulating layer can be fixed to the busbar by heating. The insulating layer can also be applied by coating, such as spraying, and then cured.

[0055] The photovoltaic module with hidden busbars of the present application can first arrange the cells according to the pattern on the module substrate, then arrange the welding strips on the cell sheets, and then use a flexible film to cover the module substrate, evacuate the area covered by the flexible film, so that the flexible film presses the welding strips and the cell sheets, and the laser penetrates the flexible film for welding. Among them, reference can be made to the public text CN118106614A, a welding, production method and product of a photovoltaic cell module. After welding is completed, the vacuum can be broken and the flexible film can be uncovered. Then, according to the setting of the insulating layer of the present application, an insulating layer is coated, glued or arranged on the welded cell sheets, and the busbars are arranged according to the pattern, and then the extension part and the first welding strip are welded by laser. It is usually photovoltaic glass and a heat-sealing material arranged thereon, such as EVA, POE, etc. Then, the heat-sealing material and photovoltaic glass are placed thereon, and laminated and packaged to form the final photovoltaic module.

[0056] In the embodiments of the present application, the spacing between adjacent cells in a row is very small, preferably zero spacing, or a negative spacing stacking. Adjacent cells are stacked with a negative spacing. When adjacent cells in a row are stacked with a negative spacing, one side of a solar cell is located below its adjacent cell, and the other side is located above its adjacent cell. The stacking dimension of adjacent cells is 0.2 to 0.5 mm.

[0057] By adopting the method of the present invention, the cells can be placed with negative spacing, thereby further improving the utilization rate of the photovoltaic module space and increasing the module power.

[0058] The above is only a preferred embodiment of the present application. Although the present application has been disclosed as a preferred embodiment, it is not intended to limit the present application. Any technician familiar with the art can use the above-disclosed methods and technical contents to make many possible changes and modifications to the technical solution of the present application without departing from the scope of the technical solution of the present application, or modify it into an equivalent embodiment with equivalent changes. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present application without departing from the content of the technical solution of the present application are still within the scope of protection of the technical solution of the present application.

Claims

1. A photovoltaic module with hidden busbars, characterized by: The photovoltaic module comprises a battery string, wherein the battery string comprises a plurality of battery cells connected in series along the X direction, and the plurality of battery strings are arranged along the Y direction on the photovoltaic module; The battery cell includes alternating positive and negative grid lines on the back side. The positive grid lines are connected by positive welding strips, and the negative grid lines are connected by negative welding strips. Two adjacent battery cells in a battery string are connected by positive welding strips or by negative welding strips. The battery further includes a bus bar, which is arranged along the Y direction and connects two adjacent battery strings. The bus bar includes a bus bar body and a plurality of extensions arranged at intervals along the extension direction of the bus bar body. The extension direction of the extension is perpendicular to the extension direction of the bus bar body. The extension is located on one side or both sides of the bus bar body and is arranged above the first welding strip and welded to the first welding strip. The busbar further comprises an insulating layer disposed below the busbar, wherein the width of the insulating layer is not less than the width of the busbar body, and the insulating layer is disposed at least on the second welding strip located below the busbar to insulate the busbar from the second welding strip; The first welding strip is a welding strip covered by the bus bar and directly connected and welded to the bus bar, and the second welding strip is a welding strip covered by the bus bar and not directly connected and welded to the bus bar; When the extension portion is located on one side of the busbar body, one end of the extension portion extends out of the busbar body, and adjacent extension portions extend out of the busbar body in the same direction; Among them, when the extension part is located on both sides of the busbar body, one end of the extension part extends out of the busbar body, and the adjacent extension parts extend out of the busbar body in opposite directions; or, both ends of the extension part extend out of the busbar body, and the lengths of adjacent extension parts extending out of the same side of the busbar body are different.

2. The photovoltaic module with hidden busbars according to claim 1, characterized in that: The extension portion and the busbar body are integrally formed, or the extension portion is fixedly arranged above or below the busbar body.

3. The photovoltaic module with hidden busbars according to claim 1, characterized in that: The width of the busbar body is 3 mm to 20 mm; And / or, the length of the extension portion extending from the busbar body is 1 mm to 60 mm.

4. The photovoltaic module with hidden busbars according to claim 1, characterized in that: The width of the extension portion is 0.1 mm to 4 mm; or the width of the extension portion is 0.5 to 4 times the width of the electrical connection welding strip.

5. The photovoltaic module with hidden busbars according to claim 1, characterized in that: The insulating layer is an insulating strip, and its extension direction is the same as the extension direction of the busbar body; Alternatively, the insulating layer is an intermittently arranged insulating strip, which covers the corresponding position of the second welding strip covered by the bus bar and is disconnected at the corresponding position of the first welding strip covered by the bus bar; Alternatively, the insulating layer includes an insulating strip body and protrusions protruding along the width direction and spaced apart in the length direction of the insulating strip body. The extension direction of the insulating strip body is the same as the extension direction of the bus bar body. The protrusions are arranged corresponding to the extension portion of the bus bar and do not exceed the extension portion.

6. A photovoltaic module with hidden busbars according to any one of claims 1 to 5, characterized in that: The busbars include three groups, which are respectively arranged on both sides of the photovoltaic module in the X direction and on a row of solar cells in the middle, namely edge busbars and middle busbars.

7. The photovoltaic module with hidden busbars according to claim 6, characterized in that: The edge bus bars include multiple bars, which connect the same-sex welding strips of a battery cell, or connect the opposite-sex welding strips of two adjacent battery cells in the Y direction, and are disconnected in the middle; the middle bus bars include multiple bars, which connect the same-sex welding strips of a battery cell, or connect the opposite-sex welding strips of two adjacent battery cells in the Y direction, and are disconnected in the middle; the position where the middle bus bar is disconnected is staggered with the position where the edge bus bar is disconnected.

8. The photovoltaic module with hidden busbars according to claim 1, characterized in that: In a battery string, the spacing between adjacent battery cells is zero spacing, or negative spacing.

9. The photovoltaic module with hidden busbars according to claim 1, characterized in that: The cell is a main grid-free back contact solar cell.

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