Photovoltaic module

Abstract

The invention provides a photovoltaic module which comprises a plurality of solar cells with gaps therebetween, each solar cell has a first surface and a second surface opposite to the first surface, and the photovoltaic module also comprises a confluence piece arranged on the second surface, an insulating piece, a plurality of first welding strips electrically connected with the confluence piece and a plurality of second welding strips insulated from the confluence piece, the projection of the confluence piece in the plane where the first face is located in the direction perpendicular to the first face is at least partially overlapped with the projection of the gap in the plane where the first face is located in the direction perpendicular to the first face. The projection, in the plane where the first face is located, of the insulating part in the direction perpendicular to the first face is at least partially overlapped with the projection, in the plane where the first face is located, of the gap in the direction perpendicular to the first face, and the projection overlapping area, in the plane where the first face is located, of the confluence part and the solar cell piece is insulated through the insulating part in the direction perpendicular to the first face. By optimizing the position relation between the welding strip and the convergence piece, the reliability and the safety of the photovoltaic module are enhanced.

Description

Technical Field

[0001] The present application relates to the field of photovoltaic technology, and in particular, to photovoltaic modules. Background Art

[0002] In today's era, solar energy has attracted much attention because of its considerable potential. Improving the photoelectric conversion efficiency of solar cells has always been at the core of solar cell design and optimization, and is a key task of utmost importance. In the process of continuous development and evolution of science and technology, the photovoltaic field has always been pursuing the goal of higher power and higher conversion efficiency per unit area of ​​components. Among them, the back-contact cell module stands out with its unique advantages of no grid lines and no solder strips on the front. However, in the layout of conventional back-contact cell modules, the busbars and the solder strips electrically connected to the busbars will cumulatively occupy a space of 30mm in width of the cell module, and this part of the occupied space cannot be used directly for power generation. Due to the existence of these busbars and solder strips, not only the effective power generation area of ​​the cell module is reduced, but also to a certain extent, the increase in module power and the reduction in cost per kilowatt-hour are limited.

[0003] Therefore, it is necessary to provide an improved photovoltaic module to overcome or reduce at least some of the disadvantages existing in the above-mentioned prior art. Summary of the invention

[0004] In order to solve the above technical problems, the present application provides a photovoltaic module, which includes a plurality of solar cells, a busbar, an insulating member, a plurality of first welding strips and a plurality of second welding strips, wherein gaps are arranged between the solar cells, and each of the solar cells has a first surface and a second surface opposite to the first surface; the busbar is arranged on the second surface of the solar cell, and the projection of the busbar in a direction perpendicular to the first surface and in a plane where the first surface is located at least partially overlaps with the projection of the gap in a direction perpendicular to the first surface and in a plane where the first surface is located; the insulating member is arranged on the second surface of the solar cell, and the projection of the insulating member in a direction perpendicular to the first surface and in a plane where the first surface is located at least partially overlaps with the projection of the gap in a direction perpendicular to the first surface and in a plane where the first surface is located at least partially overlaps, and the overlapping area of ​​the projection of the busbar and the solar cell in a direction perpendicular to the first surface and in the plane where the first surface is located is electrically insulated by the insulating member; the first welding strip is arranged on the second surface and is electrically connected to the busbar; the second welding strip is arranged on the second surface and is electrically insulated from the busbar.

[0005] Optionally, the width d of the busbar and the spacing c between the solar cells satisfy the following formula: c+k≤d≤2x+ck, wherein x is the distance from the edge pad of the solar cell to the edge of the solar cell, and k is a constant.

[0006] Optionally, the photovoltaic module has a front glass; c≤(b-2z-na) / (n-1), wherein b is the length of the front glass, n is the number of solar cells in a battery string arranged from one end to the other end of the photovoltaic module along the length of the front glass, z is the distance from the edge of the battery string at one end and the other end of the photovoltaic module to the corresponding edge of the front glass, and a is the length of the solar cell.

[0007] Optionally, a plurality of fine grid lines are arranged on the second surface of the solar cell, and a constant k satisfies the following formula: k≥2y, wherein y is the distance between adjacent fine grid lines.

[0008] Optionally, a plurality of fine grid lines are arranged on the second surface of the solar cell, and the current collector covers at least one of the fine grid lines located on the second surface of the solar cell.

[0009] Optionally, adhesive spots are further provided on the second surface of the solar cell sheet, and the current collector does not cover the adhesive spots, or partially covers the adhesive spots, or completely covers the adhesive spots.

[0010] Optionally, the adhesive dots bond the solar cell sheet to the first welding ribbon and / or the second welding ribbon.

[0011] Optionally, the bus bar, the insulating member, and the first welding strip are pre-assembled, or the bus bar, the insulating member, the first welding strip, and the second welding strip are pre-assembled.

[0012] Optionally, the insulating member includes an insulating tape or an insulating adhesive coating.

[0013] Optionally, the insulating tape includes at least one of a whole insulating tape, a plurality of small insulating tape pieces, and an insulating tape with openings.

[0014] Optionally, a projection of the busbar in a direction perpendicular to the second surface and in a plane where the second surface is located intersects both of the two solar cells adjacent to the busbar; or, intersects only one of the two solar cells adjacent to the busbar.

[0015] Optionally, part of the second welding strip spans the gap, or a projection of part of the second welding strip along a direction perpendicular to the second surface and in a plane where the second surface is located does not intersect the gap.

[0016] Optionally, at least a portion of the second welding strip is not in contact with the insulating member.

[0017] Optionally, in the thickness direction of the photovoltaic module, in the projection area of ​​the busbar, the first welding strip and the second welding strip are located on the same side of the busbar; wherein the busbar is located at the top, and the insulating member is an insulating tape with an opening, which is located between the busbar and the first welding strip and the second welding strip, electrically insulating the second welding strip from the busbar, and the first welding strip is electrically connected to the busbar at the opening; or, the insulating member includes a first insulating member and a second insulating member, the first insulating member is located between the busbar and the battery cell, the second insulating member and the first insulating member are not on the same side of the busbar, and the second insulating member is located between the second welding strip and the busbar.

[0018] Optionally, in the thickness direction of the photovoltaic module, in the projection area of ​​the busbar, the first welding strip and the second welding strip are not on the same side of the busbar; wherein the insulating member and the second welding strip are located between the busbar and the battery cell, the insulating member is located between the second welding strip and the busbar and electrically isolates the second welding strip from the busbar, the first welding strip is located on the topmost layer or between the busbar and the insulating member, or the insulating member includes a first insulating member and a second insulating member, the first insulating member is located between the first welding strip and the battery cell, the first welding strip is located between the first insulating member and the busbar, and the second insulating member is located between the busbar and the second welding strip.

[0019] Optionally, the busbar is an edge busbar and / or a middle busbar.

[0020] Optionally, the length a of the solar cell sheet satisfies the following formula: 30 mm ≤ a ≤ 110 mm; and / or the width of the solar cell sheet is between 180 mm and 220 mm.

[0021] This application hides the busbar on the backlight side of the back contact battery, so that the assembly space occupied by the busbar is greatly reduced, thereby increasing the size of the battery cell or increasing the spacing between the battery cells. Increasing the size of the battery cell can increase the light-receiving area and thus increase the power generation, while increasing the spacing between the battery cells is conducive to optimizing the heat dissipation performance inside the component, thereby further improving the power of the component and reducing the cost per kilowatt-hour. In addition, this application weakens the welding difficulty of the busbar by optimizing the positional relationship of the welding strip, reduces the risk of short-circuit anomalies, improves process quality control, reduces the defective rate of finished products, and enhances the reliability and safety of photovoltaic modules.

[0022] Based on the detailed description of the specific embodiments of the present application in combination with the accompanying drawings below, those skilled in the art will become more aware of the above and other objects, advantages and features of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the specific implementation of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific implementation or the prior art description. Obviously, the drawings described below are some implementations of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0024] Figure 1 A schematic diagram of a photovoltaic assembly according to an embodiment of the present application is shown;

[0025] Figure 2 The positional relationship between adjacent battery cells is shown in more detail;

[0026] Figure 3 It is shown that the projection of the current bus along the direction perpendicular to the first surface in the plane where the first surface is located and the projection of the gap between adjacent battery sheets along the direction perpendicular to the first surface in the plane where the first surface is located at least partially overlap;

[0027] Figure 4 is a partial schematic diagram showing a connection method of edge busbars of a photovoltaic assembly according to an embodiment of the present application;

[0028] Figure 5 yes Figure 4 A partial cross-sectional view of the photovoltaic module shown in FIG. 1 taken along line AA;

[0029] Figure 6 The partial enlarged view shows Figure 4 The edge busbar in the

[0030] Figure 7 A partial top view showing another embodiment of the edge busbar connection method;

[0031] Figure 8 A partial top view showing another embodiment of the edge busbar connection method;

[0032] Fig. 9 is a partial schematic diagram showing a central busbar connection method of a photovoltaic assembly according to an embodiment of the present application;

[0033] Fig.10 yes Fig. 9 A partial cross-sectional view of the photovoltaic module shown in FIG. 1 taken along line BB;

[0034] Fig.11 The partial enlarged view shows Fig. 9 The central manifold in the

[0035] Fig.12 is a partial schematic diagram showing a central busbar connection method of a photovoltaic assembly according to another embodiment of the present application;

[0036] Fig.13 yes Fig.12 A partial cross-sectional view of the photovoltaic module shown in FIG. 1 taken along line CC;

[0037] Fig.14 is a partial schematic diagram showing a central busbar connection method of a photovoltaic assembly according to another embodiment of the present application;

[0038] Fig.15 is a partial schematic diagram showing a central busbar connection method of a photovoltaic assembly according to another embodiment of the present application;

[0039] Fig.16 yes Fig.15 A partial cross-sectional view of the photovoltaic module shown in FIG. 1 taken along line DD;

[0040] Fig.17 A partial top view of a first variant embodiment of the edge busbar connection method is shown;

[0041] Fig.18 A partial top view of a second variant embodiment of the edge busbar connection method is shown;

[0042] Fig.19 A partial top view of a third variant embodiment of the edge busbar connection method is shown;

[0043] Fig. 20 A partial top view of a first variant embodiment of a central busbar connection method is shown;

[0044] Fig.21 A partial top view of a second variant embodiment of the central busbar connection method is shown;

[0045] Fig. 22 A schematic diagram showing an insulating tape having openings; and

[0046] Fig.23 A schematic diagram showing an insulating member in an embodiment of the present application is an insulating tape with openings. DETAILED DESCRIPTION

[0047] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present disclosure. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessary confusion of the concepts of the present disclosure.

[0048] Various structural schematic diagrams according to embodiments of the present disclosure are shown in the accompanying drawings. These figures are not drawn to scale, and some details are magnified and some details may be omitted for the purpose of clear expression. The shapes of various regions and layers shown in the figures and the relative sizes and positional relationships therebetween are only exemplary, and may deviate in practice due to manufacturing tolerances or technical limitations, and those skilled in the art may further design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0049] In the context of the present disclosure, when a layer / element is referred to as being "on" another layer / element, the layer / element may be directly on the other layer / element, or there may be an intermediate layer / element between them. In addition, if a layer / element is "on" another layer / element in one orientation, then when the orientation is reversed, the layer / element may be "under" the other layer / element. In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application clearer, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0050] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, "multiple" means two or more, unless otherwise clearly and specifically defined. "Several" means one or more, unless otherwise clearly and specifically defined.

[0051] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" 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, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0052] Figure 1 A schematic diagram of a photovoltaic assembly 1 according to an embodiment of the present application is shown; Figure 2 The positional relationship between adjacent battery cells is shown in more detail; Figure 3 It is shown that the projection of the busbar 300 in the direction perpendicular to the first surface 110 and in the plane where the first surface 110 is located at least partially overlaps with the projection of the gap between adjacent battery cells in the direction perpendicular to the first surface 110 and in the plane where the first surface 110 is located; Figure 4 is a partial schematic diagram showing a connection method of an edge busbar of a photovoltaic assembly 1 according to an embodiment of the present application; Figure 5 yes Figure 4 A partial cross-sectional view of the photovoltaic module 1 shown in FIG. 1 taken along line AA; Figure 6 The partial enlarged view shows Figure 4 The edge busbar in the Figure 7 A partial top view showing another embodiment of the edge busbar connection method; Figure 8 A partial top view showing another embodiment of the edge busbar connection method; Fig. 9 is a partial schematic diagram showing a central busbar connection method of a photovoltaic assembly 1 according to an embodiment of the present application; Fig.10 yes Fig. 9 A partial cross-sectional view of the photovoltaic module shown in FIG. 1 taken along line BB; Fig.11 The partial enlarged view shows Fig. 9 The central manifold in the Fig.12 is a partial schematic diagram showing a central busbar connection method of a photovoltaic assembly 1 according to another embodiment of the present application; Fig.13 yes Fig.12 A partial cross-sectional view of the photovoltaic module 1 shown in FIG. 1 taken along line CC; Fig.14 is a partial schematic diagram showing a central busbar connection method of a photovoltaic assembly 1 according to another embodiment of the present application; Fig.15 is a partial schematic diagram showing a central busbar connection method of a photovoltaic assembly 1 according to another embodiment of the present application; Fig.16 yes Fig.15 A partial cross-sectional view of the photovoltaic module 1 shown in FIG. 1 taken along line DD; Fig.17 A partial top view of a first variant embodiment of the edge busbar connection method is shown; Fig.18 A partial top view of a second variant embodiment of the edge busbar connection method is shown; Fig.19 A partial top view of a third variant embodiment of the edge busbar connection method is shown; Fig. 20 A partial top view of a first variant embodiment of a central busbar connection method is shown; Fig.21 A partial top view of a second variant embodiment of the central busbar connection method is shown; Fig. 22 A schematic diagram showing an insulating tape having openings; and Fig.23 A schematic diagram showing an insulating member in an embodiment of the present application is an insulating tape with openings.

[0053] like Figures 1 to 3 As shown, the photovoltaic module 1 includes a plurality of solar cells 100, a busbar 300, an insulating member 400, a plurality of first welding strips 201 and a plurality of second welding strips 202. Gaps are provided between the solar cells 100, and each solar cell 100 has a first surface 110 (see Figure 5 ) and a second surface 120 opposite to the first surface 110. The busbar 300 is arranged on the second surface 120 of the solar cell 100, and the projection of the busbar 300 in the direction perpendicular to the first surface 110 and in the plane where the first surface 110 is located at least partially overlaps with the projection of the gap between the solar cells 100 in the direction perpendicular to the first surface 110 and in the plane where the first surface 110 is located. The insulating member 400 is arranged on the second surface 120 of the solar cell, and the projection of the insulating member 400 in the direction perpendicular to the first surface 110 and in the plane where the first surface 110 is located at least partially overlaps with the projection of the gap between the solar cells 100 in the direction perpendicular to the first surface 110 and in the plane where the first surface 110 is located at least partially overlaps, and the busbar 300 and the solar cell 100 are insulated in the overlapping area of ​​the projection in the direction perpendicular to the first surface 110 and in the plane where the first surface 110 is located by the insulating member 400. The first welding strip 201 is arranged on the second surface 120 and is electrically connected to the busbar 300. The second soldering ribbon 202 is disposed on the second surface 120 and is electrically insulated from the current bus 300 .

[0054] Since the light-receiving surface of the solar cell is not blocked, the busbar does not occupy the space between the solar cells 100, thereby increasing the space occupancy rate of the light-receiving surface of the solar cell 100, so that each solar cell can absorb sunlight to the maximum extent, which not only increases the battery density per unit area and the photoelectric conversion efficiency of the photovoltaic module, but also makes the front appearance of the battery more beautiful. In addition, the present application greatly reduces the assembly space occupied by the busbar by hiding the busbar on the backlight surface of the solar cell, thereby increasing the size of the solar cell or increasing the spacing between the solar cells. Increasing the size of the solar cell can increase the light-receiving area and thus increase the power generation, while increasing the spacing between the solar cells is conducive to optimizing the heat dissipation performance inside the assembly, thereby further increasing the assembly power and reducing the cost per kilowatt-hour.

[0055] like Figure 1 As shown, two or more solar cells 100 can be connected in series in sequence to form a plurality of battery strings. The plurality of battery strings can be connected in series, in parallel, or in a combination of series and parallel to achieve current bus output. For example, the connection between the plurality of solar cells 100 can be achieved through a bus bar (also referred to as a bus bar) and a welding ribbon (also referred to as a welding strip).

[0056] like Figures 2 to 3 As shown, the backlight surface of the solar cell 100 is located on the second surface 120, and the light-facing surface of the solar cell 100 is located on the first surface 110. Figure 2 and Figure 3 In the illustrated embodiment, each solar cell 100 is provided with an electrode structure on the second surface 120, the electrode structure having a first polarity pad column including a plurality of first pads and a second polarity pad column including a plurality of second pads, wherein the polarities of the first polarity pad column and the second polarity pad column are opposite, and the first polarity pad column and the second polarity pad column are alternately arranged in the X direction on the second surface of the solar cell 100. For example, the first pad can be connected to the positive electrode fine grid line, and the second pad can be connected to the negative electrode fine grid line, wherein the first pad can be electrically connected by the first welding strip, and the second pad can be electrically connected by the second welding strip. It should be understood that the first pad and the second pad are defined only for the purpose of distinguishing pads and welding strips of different polarities, for example, the first pad can also be connected to the negative electrode fine grid line, and the second pad can be connected to the positive electrode fine grid line. Optionally, the graphic settings of the pad columns in each battery cell 100 can be the same or different.

[0057] In this application, as mentioned above, and as Figure 2 and Figure 3As shown, in the Y direction, the spacing between adjacent solar cells 100 is c, and the width d of the busbar and the spacing c of the solar cell 100 satisfy the following formula: c+k≤d≤2x+ck. Figure 2 As shown, x is the distance from the edge pad 150 of the solar cell 100 to the edge of the solar cell, and k is a constant. Optionally, the inter-cell spacing c can be selected from any value between 0 and 3 mm.

[0058] For example, the sheet spacing c can be 0.2 mm, or 0.4 mm, or 0.6 mm, or 0.8 mm, or 1.0 mm, or 1.2 mm, or 1.4 mm, or 1.6 mm, or 1.8 mm, or 2.0 mm, or 2.2 mm, or 2.4 mm, or 2.6 mm, or 2.8 mm, or 3.0 mm, or any value between any two of the above.

[0059] It should be noted that in the formula c+k≤d≤2x+ck, c+k≤d means: the overlapping width of the busbar and the battery cell is greater than or equal to k, that is, dc≥k. The purpose is to ensure the lower limit of the width of the busbar, ensure the tensile area for welding with the welding strip, and reduce the risk of tensile failure; second, to ensure that the busbar and the battery cell have a certain overlap area, avoid manufacturing offset, and avoid the busbar from deviating from the battery cell; third, the overlap area between the busbar and the battery cell is increased to reduce laminate cracking. In addition, in the formula d≤2x+ck, the distance from the edge of the busbar to the edge pad is greater than or equal to k (the sum of the distances from a single edge to the corresponding edge pad is greater than k), that is, 2x+cd≥k. The purpose is to ensure that the busbar and the edge pad are at a certain distance to avoid the appearance of tin slag and tin beads after the adjacent heterosexual welding strip is welded, the gray glue explodes the tin, and the contact with the busbar causes a short circuit; second, to avoid the manufacturing offset of the busbar and avoid the heterosexual welding strip from overlapping the busbar.

[0060] In addition, the photovoltaic module 1 has a front glass; c≤(b-2z-na) / (n-1), wherein b is the length of the front glass, n is the number of solar cells 100 in a battery string arranged from one end to the other end of the photovoltaic module 1 along the length of the front glass, z is the distance from the edge of the battery string at one end and the other end of the photovoltaic module 1 to the edge of the corresponding front glass, and a is the length of the solar cell 100, wherein the distance z≥25.8mm, preferably, the distance z is 26mm. In addition, n≥2, preferably, n can be 18, 20, 22, 24, 27, 30, 33, 36, 37, 40, 44, 45, 48, 49, 50, 54, 55, 60, 66, 72, 73, 74, 75.

[0061] Optionally, the solar cell in the embodiment of the present application can be a 2-slice cell, a 3-slice cell, a 4-slice cell, a 5-slice cell or a 6-slice cell. The length of the solar cell before separation can be 180 mm, or 181 mm, or 182 mm, or 183 mm, or 184 mm, or 185 mm, or 186 mm, or 187 mm, or 188 mm, or 189 mm, or 190 mm, or 191 mm, or 192 mm, or 193 mm, or 194 mm, or 195 mm, or 196 mm, or 197 mm, or 198 mm, or 199 mm, or 200mm, or 201mm, or 202mm, or 203mm, or 204mm, or 205mm, or 206mm, or 207mm, or 208mm, or 209mm, or 210mm, or 211mm, or 212mm, or 213mm, or 214mm, or 215mm, or 216mm, or 217mm, or 218mm, or 219mm, or 220mm, or any value between any two of the above.

[0062] The length a of the solar cell 100 satisfies the following formula: 30 mm ≤ a ≤ 110 mm. For example, the length a of the solar cell 100 may be 30 mm, or 32 mm, or 35 mm, or 38 mm, or 40 mm, or 42 mm, or 48 mm, or 50 mm, or 52 mm, or 53 mm, or 60 mm, or 64 mm, or 70 mm, or 71 mm, or 80 mm, or 90 mm, or 96 mm, or 100 mm, or 105 mm, or 106 mm, or 110 mm, or any value between any two of the above.

[0063] In addition, the width of the solar cell 100 can be between 180 mm and 220 mm. For example, the width of the solar cell 100 can be 180 mm, or 182 mm, or 184 mm, or 186 mm, or 188 mm, or 190 mm, or 192 mm, or 194 mm, or 196 mm, or 198 mm, or 200 mm, or 202 mm, or 204 mm, or 206 mm, or 208 mm, or 210 mm, or 212 mm, or 214 mm, or 216 mm, or 218 mm, or 220 mm, or any value between any two of the above.

[0064] Optionally, a plurality of fine grid lines are arranged on the second surface 120 of the solar cell 100, and the constant k≥2y. In this embodiment, the busbar 300 covers at least one fine grid line located on the second surface 120 of the solar cell 100, that is, along the direction perpendicular to the second surface 120 and in the plane where the second surface 120 is located, the busbar is arranged to have a certain overlap with the fine grid line. The reason for arranging in this way is that: first, the back of the solar cell is provided with fine grid lines and pads; and the fine grid lines have a height relative to the surface of the cell, that is, the whole is a concave-convex interface, and when the busbar is arranged, the friction force can be increased and the manufacturing deviation of the busbar can be reduced; second, the fine grid lines have a certain height, which relatively raises the busbar, which is conducive to the filling of the film, reduces the lamination cracking, and improves the reliability of the component.

[0065] Among them, Figure 2 As shown, y is the distance between adjacent fine grid lines, optionally, 0.05mm≤y≤1mm, preferably, y can be 0.5mm.

[0066] For example, the distance y can be 0.05 mm, or 0.1 mm, or 0.15 mm, or 0.2 mm, or 0.25 mm, or 0.3 mm, or 0.35 mm, or 0.4 mm, or 0.45 mm, or 0.5 mm, or 0.55 mm, or 0.6 mm, or 0.65 mm, or 0.7 mm, or 0.75 mm, or 0.8 mm, or 0.85 mm, or 0.9 mm, or 0.95 mm, or 1 mm, or any value between any two of the above.

[0067] In the above case, d≤2x+(b-2z-na) / (n-1)-2y.

[0068] In some embodiments of the present application, the busbar 300 includes an edge busbar and a center busbar. Figure 1 As shown, in the Y direction, the photovoltaic component 1 has edge solar cells 100, namely, a left edge solar cell 160 and a right edge solar cell 170, and a gap is provided between each of the edge solar cells 100 and the solar cell 100 adjacent to it in the Y direction, the size of the gap is c, and the cell spacing between any adjacent solar cells in the Y direction is c, and the projection of the edge busbar along the direction perpendicular to the first surface 110 and in the plane where the first surface 110 is located at least partially overlaps with the projection of the gap along the direction perpendicular to the first surface 110 and in the plane where the first surface 110 is located.

[0069] In some implementations, in the Y direction, a battery string column may be provided with multiple battery strings, and a central busbar is further provided between the solar cells in the middle of adjacent battery strings.

[0070] Some embodiments are listed below. For example, in a 72-panel photovoltaic module, each cell string includes 24 solar cells. In this case, the projection of the central busbar along the direction perpendicular to the first surface 110 and in the plane where the first surface 110 is located at least partially overlaps with the projection of the gap between the 12th solar cell and the 13th solar cell in the cell string along the direction perpendicular to the first surface 110 and in the plane where the first surface 110 is located. For example, in a 66-panel photovoltaic module, each cell string includes 22 solar cells. In this case, the projection of the central busbar along the direction perpendicular to the first surface 110 and in the plane where the first surface 110 is located at least partially overlaps with the projection of the gap between the 11th solar cell and the 12th solar cell in the cell string along the direction perpendicular to the first surface 110 and in the plane where the first surface 110 is located. For example, in a 54-format photovoltaic module, each cell string includes 18 solar cells. At this time, the projection of the central busbar along the direction perpendicular to the first surface 110 and in the plane where the first surface 110 is located at least partially overlaps with the projection of the gap between the 9th solar cell and the 10th solar cell in the cell string along the direction perpendicular to the first surface 110 and in the plane where the first surface 110 is located.

[0071] Next, combine Figures 4 to 22 The various connection modes of the edge busbars and the center busbars in the present application are described in more detail.

[0072] Figures 4 to 8 The figure shows the connection method of the edge busbar according to the present application.

[0073] Figures 4 to 6 A schematic diagram of a connection method of an edge busbar 311 according to an embodiment of the present application is shown. In this embodiment, the first welding strip 201 is located on a side of the busbar 311 away from the solar cell. The projection of the edge busbar 311 in a direction perpendicular to the second surface 120 and in a plane where the second surface 120 is located only intersects with one of the two solar cells adjacent to the edge busbar 311, and at least a portion of the second welding strip 202 is not in contact with the insulating member 400. In the thickness direction of the photovoltaic module 1, in the projection area of ​​the edge busbar 311, the first welding strip 201 and the second welding strip 202 are not on the same side of the edge busbar 311.

[0074] like Figures 4 to 6As shown, the projections of the edge bus 311 and the insulating member 400 along a direction perpendicular to the first surface 110 and in a plane where the first surface 110 is located at least partially overlap with the projections of the gap between the first battery cell 101 and the second battery cell 102 along a direction perpendicular to the first surface 110 and in a plane where the first surface 110 is located, wherein a stacking arrangement exists between the first battery cell 101, the second battery cell 102, the first welding strip 201, part of the second welding strip 202, the edge bus 311 and the insulating member 400.

[0075] Specifically, part of the second welding ribbon 202 on the second battery cell 102 is not in contact with the insulating member 400 and the second battery cell 102 , and part of the second welding ribbon 202 connects the first battery cell 101 and the second battery cell 102 .

[0076] like Figure 4 and Figure 5 As shown, in the projection area of ​​the edge busbar 311, the first welding strip 201 and the second welding strip 202 are not on the same side of the busbar, the first welding strip 201 is located at the top layer, and the plurality of second welding strips 202 are arranged between the insulating member 400 and the battery cell, so that the plurality of second welding strips 202 are electrically insulated from the edge busbar 311 by the insulating member 400, thereby preventing the second welding strips 202 from being electrically connected to the edge busbar 311 and causing a short circuit. In this embodiment, as Figure 5 As shown, the first welding strip 201 is located above the edge busbar 311. This arrangement, on the one hand, is conducive to the welding operation of the edge busbar 311. Since the current relevant welding equipment is quite mature, it can effectively guarantee the accuracy and stability of welding, thereby providing solid technical support and feasibility for large-scale mass production; on the other hand, in terms of quality inspection, such an arrangement enables the smooth implementation of the AI ​​inspection process after the welding is completed. With the help of advanced AI inspection technology, the welding effect of the busbar can be accurately confirmed, and defective welding products can be eliminated in a timely and effective manner, which greatly improves the overall quality and reliability of the product.

[0077] Figure 7 Another embodiment of the connection method of the edge busbar 312 is shown. Figure 6 The difference from the embodiment shown in is that the first welding strip 201 is located between the second surface 120 of the solar cell and the busbar, specifically, between the edge busbar 312 and the insulating member 400. This arrangement makes it easy to bond the first welding strip 201, the second welding strip 202, and the edge busbar 312 through the insulating member 400 to form a pre-assembled component.

[0078] Figure 8Another embodiment of the connection method of the edge busbar 313 is shown, and in this embodiment, it also includes: a bonding glue point is also provided on the second surface of the solar cell, and the bonding glue point bonds the solar cell 100 to the first welding strip 201 and / or the second welding strip 202. Optionally, the bonding glue used in the bonding glue point can be a heat-curing glue or a light-curing glue, such as a UV-curing glue.

[0079] The busbar does not cover the adhesive point, or partially covers the adhesive point, or completely covers the adhesive point. Figure 8 In the embodiment shown in Figure 7 The difference from the embodiment shown in is that Figure 8 The placement of the edge busbar 313 of the embodiment shown in FIG. 1 is slightly changed, and the edge busbar 313 covers part of the adhesive point (in Figure 7 The edge bus 313 may be closer to the pad of the second battery cell 102 .

[0080] Specifically, in this embodiment, the edge busbar 313 can be located above the solder strip at the adhesive point and welded thereto. In this way, the edge busbar 313 is located above, which has the advantage of being able to effectively improve the accuracy of solder strip placement, because the head and tail solder strips are not affected by the busbar, thereby improving the stability of the entire process.

[0081] Figures 9 to 16 Some connection modes of the central busbar according to the present application are shown.

[0082] Figures 9 to 11 A schematic diagram of a central busbar 321 connection method according to an embodiment of the present application is shown. In this embodiment, the first welding strip 201 is located on the side of the busbar away from the solar cell, and in the thickness direction of the photovoltaic module 1, in the projection area of ​​the central busbar 321, the first welding strip 201 and the second welding strip 202 are not on the same side of the busbar. Figures 9 to 11 As shown, the third battery cell 103 and the fourth battery cell 104 are arranged at intervals, and the second surfaces 120 of the third battery cell 103 and the fourth battery cell 104 are respectively provided with a plurality of first welding strips 201 and a plurality of second welding strips 202, the central bus 321 and the insulating member 400 are arranged at the second surface 120, and the projections of the central bus 321 and the insulating member 400 along the direction perpendicular to the first surface 110 and in the plane where the first surface 110 is located at least partially overlap with the projections of the gap between the third battery cell 103 and the fourth battery cell 104 along the direction perpendicular to the first surface 110 and in the plane where the first surface 110 is located, wherein a stacked arrangement exists between the third battery cell 103, the fourth battery cell 104, the first welding strip 201, part of the second welding strip 202, the central bus 321 and the insulating member 400.

[0083] like Figure 10 to Figure 11 As shown, specifically, a plurality of first welding strips 201 are arranged above the central bus 321, cross the central bus 321, and are electrically connected to the central bus 321, and a plurality of second welding strips 202 are arranged on the left and right sides of the insulating member 400 and are not in contact with the insulating member 400, so that the plurality of second welding strips 202 are electrically insulated from the central bus 321.

[0084] In this embodiment, if Fig.10 As shown, the first welding strip 201 is located above the central busbar 321. This arrangement is, on the one hand, conducive to the welding operation of the central busbar 321. Since the current relevant welding equipment is quite mature, it can effectively guarantee the accuracy and stability of welding, thereby providing solid technical support and feasibility for large-scale mass production; on the other hand, in terms of quality inspection, such an arrangement enables the AI ​​inspection process to be smoothly implemented after the welding is completed. With the help of advanced AI inspection technology, the welding effect of the busbar can be accurately confirmed, and defective welding products can be removed in a timely and effective manner, greatly improving the overall quality and reliability of the product. It should be noted that although in this embodiment, the insulating member 400 does not cover the adhesive point, in other embodiments not shown in this application, the insulating member 400 can also cover the adhesive point.

[0085] In addition, Figures 9 to 11 In the illustrated embodiment, the projection of the central busbar 321 in the direction perpendicular to the second surface 120 and in the plane where the second surface 120 is located intersects with both of the two solar cells adjacent to the busbar 321. It should be understood that for the edge busbar, the projection of the edge busbar in the direction perpendicular to the second surface 120 and in the plane where the second surface 120 is located may also intersect with both of the two solar cells adjacent to the edge busbar.

[0086] Figure 12 to Figure 13 Another embodiment of the connection method of the central busbar 322 is shown. In this embodiment, Figures 9 to 11 The difference from the embodiment shown in is that part of the second welding strip 202 is arranged below the insulating member 400. In this way, the central busbar 322 (busbar 300) and the first welding strip can be pre-assembled in advance to avoid distortion, offset, and abnormal fixation of the welding strip when it is placed, thereby improving the placement accuracy and manufacturing stability.

[0087] Fig.14 FIG. 1 shows a connection method of the central busbar of a photovoltaic module 1 according to another embodiment of the present application. In this embodiment, the stacking relationship between the third battery cell 103, the fourth battery cell 104, the second welding strip 202, the central busbar 322 and the insulating member 400 is the same as FIG. Figures 9 to 11The embodiment shown in FIG. 1 is the same as that shown in FIG. 2 , except that the first welding ribbon 201 is located between the second surface 120 of the solar cell and the busbar, specifically, between the central busbar 322 and the insulating member 400. In addition, the projection of the central busbar 322 in the plane where the second surface 120 is located in the direction perpendicular to the second surface 120 intersects with the two solar cells adjacent to the central busbar, and the second welding ribbon 202 does not contact the insulating member 400. That is, in this embodiment, the insulating member 400 is located between the first welding ribbon 201 and the cell, and electrically isolates the first welding ribbon 202 and the cell.

[0088] Figure 15 to Figure 16 Another embodiment of the connection method of the central busbar 323 is shown, in which the first welding strip 201 is located between the second surface of the solar cell and the busbar, and the projection of the central busbar 323 in the plane where the second surface 120 is located in the direction perpendicular to the second surface 120 only intersects with one of the two solar cells adjacent to the central busbar 323, and at least a portion of the second welding strip 202 is not in contact with the insulating member 400, wherein the stacking sequence between the third solar cell 103, the fourth solar cell 104, the first welding strip 201, a portion of the second welding strip 202, the central busbar 323 and the insulating member 400 is similar to Fig.14 The embodiment shown in FIG. Fig.14 The difference from the embodiment shown in is that, in this embodiment, a portion of the second welding strip 202 is in direct contact with the insulating member 400, specifically, a portion of the second welding strip 202 is disposed below the insulating member 400. In addition, in the thickness direction of the photovoltaic module 1, in the projection area of ​​the busbar 323, the first welding strip 201 and the second welding strip 202 are located on the same side of the busbar. It should be noted that, in this embodiment, the projection of the central busbar 323 and the insulating member 400 along the direction perpendicular to the second surface 120 and in the plane where the second surface 120 is located only partially overlaps with the projection of the gap between the third battery cell 103 and the fourth battery cell 104 along the direction perpendicular to the second surface 120 and in the plane where the second surface 120 is located, as shown in Fig.16As more clearly shown in FIG. 4 , the insulating member 400 only covers the edge of the third battery cell 103 and a portion of the gap between the third battery cell 103 and the fourth battery cell 104. In this embodiment, the central busbar 323 is arranged above the insulating member 400. This arrangement, on the one hand, is conducive to the welding operation of the central busbar 323. Since the current relevant welding equipment is quite mature, it can effectively guarantee the accuracy and stability of welding, thereby providing solid technical support and feasibility for large-scale mass production; on the other hand, in terms of quality inspection, such an arrangement enables the AI ​​inspection process to be smoothly implemented after welding is completed. With the help of advanced AI inspection technology, the welding effect of the busbar can be accurately confirmed, and defective welding products can be eliminated in a timely and effective manner, greatly improving the overall quality and reliability of the product.

[0089] In addition, it should be noted that part of the second welding ribbon 202 spans the gap between adjacent battery cells, or the projection of part of the second welding ribbon 202 in the plane where the second surface 120 is located along a direction perpendicular to the second surface 120 does not intersect the gap between adjacent battery cells.

[0090] Optionally, the busbar, the insulating member 400, and the first welding strip 201 can be pre-assembled. This arrangement can effectively avoid many problems that may arise from process links during the production process of the photovoltaic module 1. For example, when the conventional process is used to place the welding strip, the welding strip is often prone to distortion. This may be due to factors such as uneven external force or equipment accuracy deviation during operation, which causes the welding strip to be unable to be placed in a predetermined straight line shape; offset problems are also common, causing the welding strip to deviate from the predetermined welding position, thereby affecting the accuracy of welding and the reliability of electrical connection; in addition, there may be an abnormal situation of unfixedness, that is, the welding strip cannot be stably maintained in the set position after placement, and is prone to movement or shaking. The solution of forming a pre-assembled body in advance, because the first welding strip, the insulating member and the busbar have been stably combined before the second welding strip is placed, can provide a more accurate reference and stable basis for the placement of the second welding strip, improve the accuracy of the swinging welding strip, and thus improve the stability of the entire production process. It is particularly important to point out that when the first welding ribbon is placed, if there is a busbar underneath, there is actually an additional interface, which will increase the complexity and instability of the process to a certain extent. For example, it may cause problems such as uneven heat transfer and unreasonable stress distribution during welding. The pre-formed assembly can effectively overcome these disadvantages, optimize the production process, and improve process stability.

[0091] Furthermore, the busbar and the insulating member, the first welding strip and the second welding strip may be preassembled. Arranged in this way, the photovoltaic module 1 has similar advantages as those mentioned above during its production process, which will not be described in detail here.

[0092] Optionally, in the above-described embodiment, the insulating member 400 includes an insulating tape, and the insulating member 400 may be selected from one or more of EVA, EPE, POE, and PET.

[0093] Optionally, the insulating member 400 may include an insulating glue coating (not shown), wherein the insulating glue coating can be accurately printed on the battery cell through an insulating glue printing process, so that the battery cell obtains the relevant characteristics and functions imparted by the insulating glue coating.

[0094] Optionally, the insulating tape may include at least one of a whole strip of insulating tape, a plurality of small insulating tape pieces, and an insulating tape with openings.

[0095] Fig.17 A partial top view of a first variant embodiment of the edge busbar connection method is shown. In this embodiment, the first welding strip 201 is located on the side of the busbar away from the solar cell, and the projection of the edge busbar in a direction perpendicular to the second surface 120 and in the plane where the second surface 120 is located only intersects with one of the two solar cells adjacent to the edge busbar, and at least a portion of the second welding strip 202 does not contact the insulating member 400. In addition, in the thickness direction of the photovoltaic module 1, in the projection area of ​​the busbar, the first welding strip 201 and the second welding strip 202 are not on the same side of the busbar. Fig.17 In the embodiment shown, the insulating member 400 includes a first insulating member and a second insulating member, the first insulating member is an insulating glue coating, and the second insulating member is an insulating glue block. Fig.17 As shown, the first battery cell 101 and the second battery cell 102 are arranged at intervals, and the second surfaces of the first battery cell 101 and the second battery cell 102 are respectively provided with a plurality of first welding strips 201 and a plurality of second welding strips 202, and the edge bus 314 and the insulating glue block 330 are arranged at the second surface 120, and the projections of the edge bus 314 and the insulating glue block 330 in the direction perpendicular to the first surface 110 and in the plane where the first surface 110 is located overlap with the projections of the gap between the first battery cell 101 and the second battery cell 102 in the direction perpendicular to the first surface 110 and in the plane where the first surface 110 is located, and at least partially overlap, wherein the first battery cell 101, the second battery cell 102, the first welding strip 201, part of the second welding strip 202, the edge bus 314 and the insulating glue block 330 are stacked. Specifically, as Fig.17As shown, a plurality of second welding strips 202 are arranged between the insulating glue block 330 and the battery cell, so that the plurality of second welding strips 202 are electrically insulated from the edge bus 314 through the insulating glue block 330, thereby preventing the second welding strips 202 from being electrically connected to the edge bus 314 and causing a short circuit. The edge bus 314 is arranged between the insulating glue block 330 and the first welding strip 201, wherein the first welding strip 201 is used to electrically connect the first pad of the first battery cell 101 to the edge bus 314. In this embodiment, as Fig.17 As shown, the first welding strip 201 is located above the edge bus 314. In addition, since the surfaces of the first battery cell 101 and the second battery cell 102 are provided with an insulating adhesive coating, the edge bus 314 cannot be directly electrically connected to the surfaces of the first battery cell 101 and the second battery cell 102 when it is provided on the surfaces of the first battery cell 101 and the second battery cell 102. In other words, the insulating adhesive coating can electrically insulate the second welding strip 202 and the first welding strip 201 electrically connected to the edge bus 314 from the battery cell. In this way, on the one hand, the risk of short circuit failure or arc damage caused by the direct electrical connection between the edge bus 314 and the surface of the battery cell is avoided; on the other hand, from the perspective of production process optimization, the insulating adhesive coating replaces part of the insulating tape due to the barrier effect of the insulating tape, thereby effectively reducing the use of the insulating tape and correspondingly simplifying the complex process steps related thereto.

[0096] Fig.18 A partial top view of a second variant embodiment of the edge bus connection method is shown. In this embodiment, the first welding strip 201 is located between the second surface of the solar cell and the bus, and the projection of the edge bus 315 in a direction perpendicular to the second surface 120 and in the plane where the second surface 120 is located only intersects with one of the two solar cells adjacent to the edge bus, and at least a portion of the second welding strip 202 does not contact the insulating member 400, and in the thickness direction of the photovoltaic module 1, in the projection area of ​​the edge bus 315, the first welding strip 201 and the second welding strip 202 are not on the same side of the bus. In addition, the insulating member 400 includes a first insulating member and a second insulating member, the first insulating member is located between the first welding strip 201 and the solar cell, the first welding strip 201 is located between the first insulating member and the bus, and the second insulating member is located between the bus and the second welding strip 202. Fig.18 In the embodiment shown, the first insulating member is an insulating glue coating, and the second insulating member is a small piece of insulating glue. Fig.18As shown, the first battery cell 101 and the second battery cell 102 are arranged at intervals, and the second surfaces of the first battery cell 101 and the second battery cell 102 are respectively provided with a plurality of first welding strips 201 and a plurality of second welding strips 202, and the edge bus 315 and the insulating glue block 330 are arranged on the second surface 120, and the projections of the edge bus 315 and the insulating glue block 330 in the direction perpendicular to the first surface 110 and in the plane where the first surface 110 is located overlap with the projections of the gap between the first battery cell 101 and the second battery cell 102 in the direction perpendicular to the first surface 110 and in the plane where the first surface 110 is located, and at least partially overlap, wherein the first battery cell 101, the second battery cell 102, the first welding strip 201, part of the second welding strip 202, the edge bus 315 and the insulating glue block 330 are stacked. Specifically, as Fig.18 As shown, the insulating adhesive block 330 is disposed between the plurality of second welding strips 202 and the edge bus 315, so that the plurality of second welding strips 202 are electrically insulated from the edge bus 315 by the insulating adhesive block 330, thereby preventing the second welding strips 202 from being electrically connected to the edge bus 315 and causing a short circuit. The first welding strip 201 is disposed between the battery cell and the edge bus 315, and is electrically connected to the edge bus 315, wherein the first welding strip 201 is used to electrically connect the first pad of the first battery cell 101 to the edge bus 315. In this embodiment, since the surfaces of the first battery cell 101 and the second battery cell 102 are provided with an insulating adhesive coating, the edge bus 315 and the first welding strip 201 cannot be directly electrically connected to the surfaces of the first battery cell 101 and the second battery cell 102 when they are provided on the surfaces of the first battery cell 101 and the second battery cell 102. That is to say, the insulating adhesive coating can electrically insulate the edge bus 314 and the first welding strip 201 electrically connected to the edge bus 314 from the battery cell, thereby avoiding the short circuit between the bus and the battery cell by printing the insulating adhesive coating. In this way, on the one hand, the risk of short circuit failure or arc damage caused by the direct electrical connection between the edge bus 315 and the first welding strip 201 and the surface of the battery cell is avoided; on the other hand, from the perspective of production process optimization, the insulating adhesive coating replaces part of the insulating tape due to the barrier effect of the insulating adhesive coating, thereby effectively reducing the use of the insulating tape and correspondingly simplifying the complex process steps related thereto.

[0097] Fig.19A partial top view of a third variant embodiment of the edge busbar connection method is shown. In this embodiment, the first welding strip 201 is located on the side of the busbar away from the solar cell, and the projection of the edge busbar in a direction perpendicular to the second surface 120 and in the plane where the second surface 120 is located only intersects with one of the two solar cells adjacent to the edge busbar, and at least a portion of the second welding strip 202 does not contact the insulating member 400, and in the thickness direction of the photovoltaic module 1, in the projection area of ​​the busbar, the first welding strip 201 and the second welding strip 202 are located on the same side of the busbar. In addition, the insulating member 400 includes a first insulating member and a second insulating member, the first insulating member is located between the busbar and the solar cell, the second insulating member and the first insulating member are located on different sides of the busbar, and the second insulating member is located between the second welding strip 202 and the busbar. Fig.18 The difference from the embodiment in is that the first welding strip 201 is arranged above the edge busbar 316 and is electrically connected to the edge busbar 316. This arrangement is, on the one hand, conducive to the welding operation of the edge busbar 316. Since the current relevant welding equipment is quite mature, it can effectively guarantee the accuracy and stability of welding, thus providing solid technical support and feasibility for large-scale mass production; on the other hand, in terms of quality inspection, such an arrangement enables the AI ​​inspection process to be smoothly implemented after welding is completed. With the help of advanced AI inspection technology, the welding effect of the busbar can be accurately confirmed, and defective welding products can be eliminated in a timely and effective manner, greatly improving the overall quality and reliability of the product.

[0098] Fig. 20 A partial top view of a modified embodiment 1 of the central busbar connection method is shown. In this embodiment, the first welding strip 201 is located on the side of the busbar away from the solar cell, and the projection of the central busbar in the direction perpendicular to the second surface 120 and in the plane where the second surface 120 is located intersects with the two solar cells adjacent to the central busbar. In the thickness direction of the photovoltaic module 1, in the projection area of ​​the busbar, the first welding strip 201 and the second welding strip 202 are not on the same side of the busbar. Fig. 20 In the embodiment shown, the insulating member 400 includes a first insulating member and a second insulating member, the first insulating member is an insulating glue coating, and the second insulating member is an insulating glue block. Fig. 20As shown, the third battery cell 103 and the fourth battery cell 104 are arranged at intervals, and the second surfaces 120 of the third battery cell 103 and the fourth battery cell 104 are respectively provided with a plurality of first welding strips 201 and a plurality of second welding strips 202, and the central bus 324 and the small insulating glue block 330 are arranged on the second surface 120, and the projections of the central bus 324 and the small insulating glue block 330 in the direction perpendicular to the first surface 110 and in the plane where the first surface 110 is located overlap with the projections of the gap between the third battery cell 103 and the fourth battery cell 104 in the direction perpendicular to the first surface 110 and in the plane where the first surface 110 is located, and the third battery cell 103, the fourth battery cell 104, the first welding strip 201, the second welding strip 202, the central bus 324 and the small insulating glue block 330 are at least partially overlapped. Fig. 20 As shown, a plurality of first welding strips 201 are arranged above the central busbar 324, so that the first welding strips 201 are electrically connected to the central busbar 324, and a plurality of second welding strips 202 are arranged between the insulating glue block 330 and the battery cell, and the second welding strips 202 are electrically insulated from the central busbar 324 by the insulating glue block 330. Fig. 20 As shown, an insulating glue block 330 is provided below the central busbar 324, and the insulating glue block 330 is provided between the second welding strip 202 and the central busbar 324. In addition, since the surfaces of the first battery cell 101 and the second battery cell 102 are provided with an insulating glue coating, in the area where the insulating glue block 330 is not provided, the central busbar 324 is prevented from being directly electrically connected to the battery cell and causing a short circuit.

[0099] Fig.21 A partial top view of a second variant embodiment of the central busbar connection method is shown. In this embodiment, the second welding strip 202 is located between the second surface of the solar cell and the busbar, and in the thickness direction of the photovoltaic module 1, in the projection area of ​​the busbar 324, the first welding strip 201 and the second welding strip 202 are located on the same side of the busbar. Fig.21 In the illustrated embodiment, the insulating member 400 includes a first insulating member and a second insulating member, wherein the first insulating member is an insulating glue coating, and the second insulating member is a small piece of insulating glue. Fig. 20 The embodiment in is different in that, Fig.21 As shown, the first welding strip 201 is arranged below the central bus 325 and is electrically connected to the central bus 325, and is electrically insulated from the battery cell by the insulating glue coating on the surface of the battery cell. That is, the insulating glue coating can electrically insulate the second welding strip 202 and the first welding strip 201 electrically connected to the central bus 324 from the battery cell, and the small piece of insulating glue can electrically insulate the second welding strip 202 from the central bus 324.

[0100] Fig. 22 FIG. 4 is a schematic diagram showing an insulating tape 410 having openings at an edge busbar. Fig. 22 As shown, the insulating tape 410 with openings is used to electrically insulate the second soldering tape 202 from the busbar and to electrically connect the first soldering tape 201 to the busbar, wherein the insulating perforated tape 410 is provided with holes 401 . Fig.23 A schematic diagram showing an insulating member in an embodiment of the present application as an insulating tape with openings is shown, Fig.23 As shown, in this embodiment, part of the second welding strip 202 is located between the second surface of the solar cell and the bus bar, the bus bar 318 is located at the top, and the insulating member 410 is an insulating tape with an opening, which is located between the bus bar 318 and the first welding strip 201 and the second welding strip 202, electrically insulating the second welding strip 202 from the bus bar 318, and the first welding strip 201 is electrically connected to the bus bar 318 at the opening, and the projection of the bus bar along the direction perpendicular to the second surface 120 and in the plane where the second surface 120 is located only intersects with one of the two solar cells adjacent to the bus bar, and at least a portion of the second welding strip 202 does not contact the insulating member 400, and in the thickness direction of the photovoltaic module 1, in the projection area of ​​the bus bar 324, the first welding strip 201 and the second welding strip 202 are located on the same side of the bus bar. The first battery cell 101 and the second battery cell 102 are arranged at intervals, and the second surfaces 120 of the first battery cell 101 and the second battery cell 102 are respectively provided with a plurality of first welding strips 201 and a plurality of second welding strips 202, and the edge bus 318 and the insulating perforated tape 410 are arranged at the second surface 120, and the projections of the edge bus 318 and the insulating perforated tape 410 in the direction perpendicular to the first surface 110 and in the plane where the first surface 110 is located at least partially overlap with the projections of the gap between the first battery cell 101 and the second battery cell 102 in the direction perpendicular to the first surface 110 and in the plane where the first surface 110 is located. There is a stacked arrangement between the first battery cell 101, the second battery cell 102, the first welding strip 201, part of the second welding strip 202, the edge bus 318 and the insulating perforated tape 410. Fig.23 As shown, a plurality of second welding strips 202 are arranged between the insulating perforated tape 410 and the battery cell, wherein the insulating perforated tape 410 is not provided with holes at the position in contact with the second welding strips 202, so that the plurality of second welding strips 202 are electrically insulated from the edge bus 318 through the insulating perforated tape 410, thereby preventing the second welding strips 202 from being electrically connected to the edge bus 318 and causing a short circuit. Similarly, a plurality of first welding strips 201 are arranged between the insulating perforated tape 410 and the battery cell, wherein the insulating perforated tape 410 is provided with holes 401 at the position in contact with the first welding strips 201, so that the plurality of first welding strips 201 are electrically connected to the edge bus 318 through the holes 401 of the insulating perforated tape 410, thereby electrically connecting the first solder pad of the first battery cell 101 to the edge bus 318. In this embodiment, as Fig.23As shown and described above, since the insulating perforated tape 410 is provided with a hole 401 at the position in contact with the first welding ribbon 201, the first welding ribbon 201 can be directly in contact with the edge bus 318 through the hole 401 of the insulating perforated tape 410 to form an electrical connection. It should be noted that, similar to the aforementioned embodiment, the insulating member 400 includes an insulating adhesive coating, and the first welding ribbon 201 and the second welding ribbon 202 are electrically insulated from the battery cell through the insulating adhesive coating.

[0101] It should be noted that in Figures 17 to 23 In the embodiment shown in , similarly, the busbar, the insulating member, and the first welding strip 201 may be a pre-assembled body; or, the busbar, the insulating member, the first welding strip 201, and the second welding strip 202 may be a pre-assembled body.

[0102] This application hides the busbar on the back of the back-contact battery, so that the assembly space occupied by the busbar is greatly reduced, thereby increasing the size of the battery cell or increasing the spacing between the battery cells. Increasing the size of the battery cell can increase the light-receiving area and thus increase the power generation, while increasing the spacing between the battery cells is conducive to optimizing the heat dissipation performance inside the component, thereby further improving the power of the component and reducing the cost per kilowatt-hour. In addition, this application reduces the welding difficulty of the busbar by optimizing the positional relationship of the welding strip, reduces the risk of short-circuit anomalies, improves process quality control, reduces the defective rate of finished products, and enhances the reliability and safety of solar cells.

[0103] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "an example", "some embodiments", or "preferred embodiment" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0104] The embodiments of the present application are described in detail above. However, aspects of the present application are not limited to the above embodiments. Various modifications and substitutions may be applied to the above embodiments without departing from the scope of the present application.

Claims

1. A photovoltaic module, characterized in that: include: A plurality of solar cells, wherein gaps are provided between the solar cells, and each of the solar cells has a first surface and a second surface opposite to the first surface; A busbar, wherein the busbar is arranged on the second surface of the solar cell, and a projection of the busbar in a direction perpendicular to the first surface and in a plane where the first surface is located at least partially overlaps with a projection of the gap in a direction perpendicular to the first surface and in a plane where the first surface is located; an insulating member, wherein the insulating member is arranged on the second surface of the solar cell, a projection of the insulating member in a direction perpendicular to the first surface and in a plane where the first surface is located at least partially overlaps with a projection of the gap in a direction perpendicular to the first surface and in a plane where the first surface is located, and an overlapping area of ​​the projections of the busbar and the solar cell in a direction perpendicular to the first surface and in a plane where the first surface is located is electrically insulated by the insulating member; A plurality of first welding strips, wherein the first welding strips are arranged on the second surface and are electrically connected to the busbar; as well as A plurality of second welding strips are provided on the second surface and are electrically insulated from the bus bar.

2. The photovoltaic module according to claim 1, characterized in that: The width d of the busbar and the spacing c between the solar cells satisfy the following formula: c+k≤d≤2x+ck, wherein x is the distance from the edge pad of the solar cell to the edge of the solar cell, and k is a constant.

3. The photovoltaic module according to claim 2, characterized in that: The photovoltaic module has a front glass; c≤(b-2z-na) / (n-1), wherein b is the length of the front glass, n is the number of solar cells in a battery string arranged from one end to the other end of the photovoltaic module along the length of the front glass, z is the distance from the edge of the battery string at one end and the other end of the photovoltaic module to the corresponding edge of the front glass, and a is the length of the solar cell.

4. The photovoltaic module according to claim 2, characterized in that: A plurality of fine grid lines are arranged on the second surface of the solar cell sheet, and a constant k satisfies the following formula: k≥2y, wherein y is the distance between adjacent fine grid lines.

5. The photovoltaic module according to any one of claims 1 to 4, characterized in that: A plurality of fine grid lines are arranged on the second surface of the solar cell, and the current collector covers at least one of the fine grid lines on the second surface of the solar cell.

6. The photovoltaic module according to any one of claims 1 to 4, characterized in that: Adhesive spots are also arranged on the second surface of the solar cell sheet, and the current collector does not cover the adhesive spots, or partially covers the adhesive spots, or completely covers the adhesive spots.

7. The photovoltaic module according to claim 6, characterized in that: The adhesive dots bond the solar cell sheet to the first welding ribbon and / or the second welding ribbon.

8. The photovoltaic module according to any one of claims 1 to 7, characterized in that: The busbar, the insulating member, and the first welding strip are pre-assembled, or the busbar, the insulating member, the first welding strip, and the second welding strip are pre-assembled.

9. The photovoltaic module according to any one of claims 1 to 7, characterized in that: The insulating member includes an insulating tape or an insulating adhesive coating.

10. The photovoltaic module according to claim 9, characterized in that: The insulating tape includes at least one of a whole insulating tape, a plurality of insulating tape blocks, and an insulating tape with openings.

11. The photovoltaic module according to any one of claims 1 to 10, characterized in that: The projection of the busbar in the plane where the second surface is located along a direction perpendicular to the second surface intersects both of the two solar cells adjacent to the busbar; or intersects only one of the two solar cells adjacent to the busbar.

12. The photovoltaic module according to any one of claims 1 to 11, characterized in that: Part of the second welding strip spans the gap, or a projection of part of the second welding strip along a direction perpendicular to the second surface and in a plane where the second surface is located does not intersect the gap.

13. The photovoltaic module according to any one of claims 1 to 11, characterized in that: At least a portion of the second welding strip is not in contact with the insulating member.

14. The photovoltaic module according to any one of claims 1 to 13, characterized in that: In the thickness direction of the photovoltaic module, in the projection area of ​​the busbar, the first welding strip and the second welding strip are located on the same side of the busbar; wherein, The busbar is located at the top, the insulating member is an insulating tape with an opening, located between the busbar and the first welding strip and the second welding strip, electrically insulating the second welding strip from the busbar, and the first welding strip is electrically connected to the busbar at the opening, Alternatively, the insulating member includes a first insulating member and a second insulating member, the first insulating member is located between the bus bar and the battery cell, the second insulating member and the first insulating member are not on the same side of the bus bar, and the second insulating member is located between the second welding strip and the bus bar.

15. The photovoltaic module according to any one of claims 1 to 13, characterized in that: In the thickness direction of the photovoltaic module, in the projection area of ​​the busbar, the first welding strip and the second welding strip are not on the same side of the busbar; wherein, The insulating member and the second welding strip are located between the busbar and the battery cell, the insulating member is located between the second welding strip and the busbar and electrically isolates the second welding strip from the busbar, and the first welding strip is located at the top layer or between the busbar and the insulating member. Alternatively, the insulating member includes a first insulating member and a second insulating member, wherein the first insulating member is located between the first welding strip and the battery cell, the first welding strip is located between the first insulating member and the bus bar, and the second insulating member is located between the bus bar and the second welding strip.

16. The photovoltaic module according to any one of claims 1 to 15, characterized in that: The busbar is an edge busbar and / or a middle busbar.

17. The photovoltaic module according to any one of claims 1 to 16, characterized in that: The length a of the solar cell sheet satisfies the following formula: 30 mm ≤ a ≤ 110 mm; and / or the width of the solar cell sheet is between 180 mm and 220 mm.

Images