Solar cell and solar cell module

Abstract

The utility model discloses a solar cell sheet and a solar cell module, the solar cell sheet comprises a cell sheet main body and a plurality of auxiliary grid lines which are distributed on the surface of the cell sheet main body in parallel, and the auxiliary grid lines are provided with a plurality of groups of reinforcing lines which are distributed along the direction perpendicular to the extension direction of the auxiliary grid lines. The surface of each reinforcing line in each group of reinforcing lines is provided with one or more recessed parts distributed along the extension direction of the auxiliary grid lines, and the width of each reinforcing line is larger than that of the auxiliary grid line connected with the reinforcing line. According to the solar cell sheet and the solar cell assembly, the contact area between the welding strip and the auxiliary grid line reinforcing line can be increased, the welding area between the welding strip and the auxiliary grid line reinforcing line is further increased, and the welding tension is improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of solar cells, and in particular relates to a solar cell cell and a solar cell assembly. Background Art

[0002] With the rapid development of the photovoltaic industry, the performance and efficiency requirements of solar cells in the domestic and international photovoltaic markets are constantly increasing, and industry manufacturers have focused on the research and development of high-efficiency batteries.

[0003] Existing solar cells are provided with grid lines to collect the current on the cells. In the process of manufacturing battery modules, it is often necessary to weld welding strips on the cells to electrically connect the grid lines on the cells. The current is collected along the welding strips to the busbars, and finally led out from the busbars through leads.

[0004] However, in the existing solar cell, the contact area between the grid lines and the round wire-shaped welding ribbon when welding is small, resulting in a small welding tension of the welding ribbon relative to the solar cell.

[0005] The information disclosed in this background technology section is only intended to increase the understanding of the overall background of the present invention, and should not be regarded as acknowledging or suggesting in any form that the information constitutes the prior art already known to a person skilled in the art. Utility Model Content

[0006] The utility model aims to provide a solar cell sheet and a solar cell assembly, which can increase the contact area between the welding strip and the auxiliary grid line reinforcement line, thereby increasing the welding area of ​​the two and improving the welding tension.

[0007] In order to achieve the above purpose, the technical solution provided by a specific embodiment of the utility model is as follows:

[0008] A solar cell comprises a cell body and a plurality of secondary grid lines distributed in parallel on the surface of the cell body, wherein the secondary grid lines are provided with a plurality of groups of reinforcing lines distributed in a direction perpendicular to the extension direction of the secondary grid lines, and the surface of each reinforcing line in each group of reinforcing lines is formed with one or more recessed portions distributed in the extension direction of the secondary grid lines, and the width of each reinforcing line is greater than the width of the secondary grid line connected thereto.

[0009] In one or more embodiments of the present invention, the surface of the recessed portion is arranged in an arc shape along the extension direction of the secondary grid line.

[0010] In one or more embodiments of the present invention, the reinforcing line includes a base and extensions located at two ends of the base, the recessed portion is disposed on the base, and the extension is integrally connected to the secondary grid line.

[0011] In one or more embodiments of the present invention, at least two adjacent recessed portions are disposed on the base, and an arc-shaped receiving surface is formed in the recessed portion to receive a welding strip.

[0012] In one or more embodiments of the present invention, the width of the extension portion gradually decreases from the base portion to the end portion, and the end of the extension portion is connected to the secondary grid line; and / or,

[0013] The thickness of the extension portion remains constant or gradually decreases from the base portion to the end portion, and the thickness of the extension portion is greater than the thickness at the center position of the recessed portion.

[0014] In one or more embodiments of the present invention, the length of the reinforcement line is 500 μm to 1500 μm; and / or,

[0015] The width of the reinforcement line is 50 μm to 150 μm; and / or,

[0016] The thickness of the reinforcement line is 3 μm to 10 μm.

[0017] In one or more embodiments of the present invention, the length of the base is 400 μm to 1400 μm; and / or,

[0018] The length of the extension portion is 50 μm to 150 μm.

[0019] In one or more embodiments of the present invention, the width of the recessed portion is 35 μm to 135 μm; and / or,

[0020] The depth of the recessed portion ranges from 2 μm to 6 μm.

[0021] In one or more embodiments of the present invention, the secondary grid lines and the reinforcement lines are located on the light-receiving surface and / or the backlight surface of the battery cell body.

[0022] A specific embodiment of the utility model further provides a solar cell assembly, comprising:

[0023] The above-mentioned solar cell;

[0024] A plurality of welding strips, each of which is welded to each group of reinforcing wires in a direction perpendicular to the extension direction of the secondary grid lines;

[0025] The welding strip is at least partially accommodated in the recessed portion of the reinforcing wire, and the diameter or width of the welding strip is smaller than the length of the reinforcing wire.

[0026] Compared with the prior art, the solar cell sheet and solar cell assembly of the utility model provide a recessed portion on the reinforcement line of the secondary grid line to accommodate the welding strip, thereby increasing the contact area between the welding strip and the reinforcement line of the secondary grid line, increasing the welding area of ​​the two, and improving the welding tension.

[0027] The solar cell sheet and solar cell assembly of the utility model reduce the amount of silver paste used in the reinforcing wire and save costs by specially setting the shape of the reinforcing wire extension part.

[0028] In the solar cell sheet and solar cell assembly of the utility model, the welding strip can be better placed in the concave portion of the reinforcement line and is not prone to deviation. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0030] Figure 1 This is a schematic diagram of the planar structure of a solar cell in one embodiment of the utility model;

[0031] Figure 2 for Figure 1 Schematic diagram of the local structure at A in the middle;

[0032] Figure 3 A top view of a reinforcing wire in a solar cell sheet in one embodiment of the utility model;

[0033] Figure 4 It is a front view of a reinforcing wire in a solar cell sheet in one embodiment of the utility model;

[0034] Figure 5 A top view of a reinforcing wire in a solar cell sheet in another embodiment of the utility model;

[0035] Figure 6 A top view of a reinforcing wire in a solar cell sheet in another embodiment of the utility model;

[0036] Figure 7 It is a front view of a reinforcing wire in a solar cell sheet in another embodiment of the utility model;

[0037] Figure 8 for Figure 7 Schematic diagram of the local structure at B in the middle;

[0038] Fig. 9It is a front view of a reinforcing wire in a solar cell sheet in another embodiment of the utility model;

[0039] Fig.10 for Fig. 9 Schematic diagram of the local structure at C in the middle;

[0040] Fig.11 It is a front view of a reinforcing wire in a solar cell sheet in another embodiment of the utility model;

[0041] Fig.12 for Fig.11 Schematic diagram of the local structure at D in the middle;

[0042] Fig.13 This is a cross-sectional view of the contact between the reinforcement wire and the welding ribbon in a solar cell assembly in one embodiment of the utility model. DETAILED DESCRIPTION

[0043] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0044] Furthermore, it should be understood that although the terms first, second, etc. can be used to describe various elements or structures in this article, these described objects should not be limited by these terms. These terms are only used to distinguish these described objects from each other. For example, the first main grid line can be called the second main grid line, and similarly the second main grid line can also be called the first main grid line, which does not deviate from the protection scope of the present utility model.

[0045] As mentioned in the background technology, grid lines are set on solar cells to collect the current on the cells. In the process of manufacturing battery modules, it is often necessary to weld welding strips on the cells to electrically connect the grid lines on the cells. The current is collected along the welding strips to the busbars and finally led out from the busbars through the leads. However, the contact area between the grid lines on the existing solar cells and the round wire-shaped welding strips is small when welding, resulting in a small welding tension of the welding strip relative to the cell.

[0046] In order to solve the above technical problems, the utility model provides a solar cell sheet and a solar cell module, by setting a recessed portion on the reinforcement line of the secondary grid line, so that the welding strip can be located in the recessed portion when welded to the reinforcement line of the secondary grid line, thereby increasing the contact area between the welding strip and the reinforcement line of the secondary grid line, increasing the welding area of ​​the two, and improving the welding tension.

[0047] The present invention is further described below with reference to specific examples.

[0048] like Figures 1 to 4 As shown, a solar cell in an embodiment of the utility model comprises a cell body 10 and a plurality of secondary grid lines 20 parallel to the surface of the cell body 10. The secondary grid lines 20 are provided with a plurality of reinforcing wires 30 distributed along a direction perpendicular to the extension direction of the secondary grid lines 20, and the reinforcing wires 30 are provided with a recessed portion 311.

[0049] The cell body 10 generally includes two identical half-cells with a cut line reserved in the middle. Multiple secondary grid lines 20 are distributed in parallel on the light-receiving surface and / or the backlight surface of each half-cell. Exemplarily, the spacing between adjacent secondary grid lines 20 can be 1.246±0.02 mm.

[0050] In this embodiment, a plurality of reinforcing wires 30 are arranged on each secondary grid line 20, and these reinforcing wires 30 are equally spaced and distributed on the secondary grid line 20 to connect the entire secondary grid line 20, and the width of the reinforcing wire 30 is greater than the width of the secondary grid line 20 connected thereto. Exemplarily, the spacing between adjacent reinforcing wires 30 may be 10.29 mm; the width of the secondary grid line 20 may be 0.02 mm. Multiple groups of reinforcing wires 30 are respectively arranged on multiple secondary grid lines 20 along a direction perpendicular to the extension direction of the secondary grid lines 20, and the reinforcing wires 30 on adjacent secondary grid lines 20 are arranged correspondingly.

[0051] The length of each reinforcing wire 30 is about 500 μm to 1500 μm. The width of each reinforcing wire 30 is about 50 μm to 150 μm. The thickness of each reinforcing wire 30 is about 3 μm to 10 μm. Exemplarily, the total length of the reinforcing wire 30 is 1000 μm, the maximum width is 80 μm, and the maximum thickness is 5 μm.

[0052] refer to Figure 3 and Figure 4 As shown, the surface of each reinforcing line 30 is formed with one or more recessed portions 311 distributed along the extending direction of the secondary grid line 20 and recessed toward the battery cell body 10 .

[0053] Specifically, the reinforcing wire 30 includes a base 31 and extensions 32 located at both ends of the base 31, and the extensions 32 are integrally connected to the secondary grid line 20. The length of the base 31 is 400 μm to 1400 μm, and the length of the extension 32 is 50 μm to 150 μm. One or more recesses 311 are provided on the base 31 of the reinforcing wire 30. When a plurality of recesses 311 are provided on the base 31, the plurality of recesses 311 are adjacent to each other and are provided without spacing.

[0054] It is understandable that the soldering strip is arranged on the reinforcing wire 30 perpendicular to the extension direction of the secondary grid line 20. Therefore, in the extension direction perpendicular to the secondary grid line 20, the corresponding recessed parts 311 on the reinforcing wire 30 are preferably arranged one by one to facilitate the placement of the soldering strip.

[0055] In order to make the recessed portion 311 fit better with the soldering strip to be soldered, in this embodiment, the surface of the recessed portion 311 is arranged in an arc shape along the extension direction of the secondary grid line 20. That is, an arc-shaped receiving surface is formed in each recessed portion 311 to receive a soldering strip. Preferably, the curvature of the arc-shaped receiving surface of the recessed portion 311 is substantially the same as the curvature of the peripheral surface of the soldering strip to be soldered.

[0056] Exemplarily, the width of the recessed portion 311 is about 35 μm to 135 μm, preferably 85 μm. The depth of the recessed portion 311 is in the range of 2 μm to 6 μm, preferably 4 μm.

[0057] In the embodiment of the utility model, by setting the recessed portion 311 on the reinforcing wire 30, the welding strip can be at least partially located in the recessed portion 311 when welded to the reinforcing wire 30 of the secondary grid line 20, thereby increasing the contact area between the welding strip and the reinforcing wire 30 of the secondary grid line 20, increasing the welding area of ​​the two, and improving the welding tension.

[0058] It can be understood that the secondary grid line 20 and the reinforcing line 30 are both printed by conductive paste. In order to save conductive paste, the width of the extension part 32 of the reinforcing line 30 gradually decreases from the base 31 to the end, and the end of the extension part 32 is connected to the secondary grid line 20; the thickness of the extension part 32 of the reinforcing line 30 remains unchanged or gradually decreases from the base 31 to the end, and the thickness of the extension part 32 is greater than the thickness at the center of the recessed part 311.

[0059] Exemplary, reference Figure 3 As shown, in a specific embodiment of the present invention, the width of the extension portion 32 of the reinforcement line 30 gradually decreases linearly from the base portion 31 toward the end portion.

[0060] Exemplary, reference Figure 5 As shown, in another specific embodiment of the present invention, the width of the extension portion 32 of the reinforcement line 30 decreases exponentially from the base portion 31 toward the end portion, that is, the two side edges of the extension portion 32 extend close to each other in a concave arc shape.

[0061] Exemplary, reference Figure 6 As shown, in another specific embodiment of the present invention, the width of the extension portion 32 of the reinforcement line 30 decreases logarithmically from the base 31 toward the end, that is, the two side edges of the extension portion 32 extend close to each other in a convex arc shape.

[0062] Exemplary, reference Figure 7 and Figure 8 As shown, in another specific embodiment of the present invention, the thickness of the extension portion 32 of the reinforcement line 30 gradually decreases linearly from the base portion 31 toward the end portion, that is, the upper surface of the extension portion 32 is an inclined plane.

[0063] Exemplary, reference Fig. 9 and Fig.10 As shown, in another specific embodiment of the present invention, the thickness of the extension portion 32 of the reinforcement line 30 decreases exponentially from the base portion 31 toward the end portion, that is, the upper surface of the extension portion 32 is an inclined concave surface.

[0064] Exemplary, reference Fig.11 and Fig.12 As shown, in another specific embodiment of the present invention, the thickness of the extension portion 32 of the reinforcement line 30 decreases gradually from the base portion 31 toward the end portion in a logarithmic pattern, that is, the upper surface of the extension portion 32 is an inclined convex surface.

[0065] The solar cell sheet and solar cell assembly of the utility model reduce the amount of silver paste used in the reinforcing wire 30 and save costs by specially setting the shape of the extension portion 32 of the reinforcing wire 30 .

[0066] Ginseng Fig.13 As shown, a solar cell assembly in an embodiment of the utility model includes a solar cell and a welding strip 200. The auxiliary grid lines 20 and the reinforcing lines 30 on the light-receiving surface and / or the backlight surface of the solar cell are the same as those in the above embodiment and will not be described in detail here.

[0067] In this embodiment, each welding strip 200 is welded to a row of reinforcing wires 30 in a direction perpendicular to the extension direction of the secondary grid lines 30. The diameter or width of the welding strip 200 in this embodiment is smaller than the length of the reinforcing wires 30. Preferably, the curvature of the circumferential surface of the welding strip 200 is the same as the curvature of the surface of the recessed portion 311 on the reinforcing wire 30, so that when the welding strip 200 is at least partially placed in the recessed portion 311, it can be completely attached to the surface of the recessed portion 311 for better welding. The welding strip 200 is electrically connected to the reinforcing wires 30, thereby achieving conduction of the secondary grid lines 20 electrically connected to the reinforcing wires 30.

[0068] The structure of multiple solar cells connected in series in the solar cell assembly is exactly the same as that in the prior art, and the series structure will not be described in detail here.

[0069] Compared with the prior art, in the solar cell assembly of the present invention, the welding strip 200 can be better placed in the recessed portion 311 of the reinforcing wire 30, is less likely to be offset, and has a large contact area, thereby providing a strong welding tensile force.

[0070] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-restrictive from any point of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention. Any reference numeral in a claim should not be regarded as limiting the claim to which it relates.

[0071] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A solar cell, characterized in that: It includes a battery cell body and a plurality of secondary grid lines distributed in parallel on the surface of the battery cell body, wherein the secondary grid lines are provided with a plurality of groups of reinforcing lines distributed along a direction perpendicular to the extension direction of the secondary grid lines, and the surface of each reinforcing line in each group of reinforcing lines is formed with one or more recessed portions distributed along the extension direction of the secondary grid lines, and the width of each reinforcing line is greater than the width of the secondary grid line connected to it.

2. The solar cell according to claim 1, characterized in that: The surface of the recessed portion is arranged in an arc shape along the extending direction of the secondary gate line.

3. The solar cell according to claim 1, characterized in that: The reinforcing line comprises a base and extensions located at two ends of the base, the recessed portion is arranged on the base, and the extension is integrally connected with the auxiliary grid line.

4. The solar cell according to claim 3, characterized in that: At least two adjacent recessed parts are arranged on the base, and an arc-shaped receiving surface is formed in the recessed part to receive a welding strip.

5. The solar cell according to claim 3, characterized in that: The width of the extension portion gradually decreases from the base portion to the end portion, and the end of the extension portion is connected to the secondary grid line; and / or, The thickness of the extension portion remains constant or gradually decreases from the base portion to the end portion, and the thickness of the extension portion is greater than the thickness at the center position of the recessed portion.

6. The solar cell according to claim 1, characterized in that: The length of the reinforcement line is 500 μm to 1500 μm; and / or, The width of the reinforcement line is 50 μm to 150 μm; and / or, The thickness of the reinforcement line is 3 μm to 10 μm.

7. The solar cell according to claim 3, characterized in that: The length of the base is 400 μm to 1400 μm; and / or, The length of the extension portion is 50 μm to 150 μm.

8. The solar cell according to claim 3, characterized in that: The width of the recessed portion is 35 μm to 135 μm; and / or, The depth of the recessed portion ranges from 2 μm to 6 μm.

9. The solar cell according to claim 1, characterized in that: The secondary grid lines and the reinforcing lines are located on the light-receiving surface and / or the backlight surface of the battery cell body.

10. A solar cell module, characterized in that: include: The solar cell according to any one of claims 1 to 9; A plurality of welding strips, each of which is welded to each group of reinforcing wires in a direction perpendicular to the extension direction of the secondary grid lines; The welding strip is at least partially accommodated in the recessed portion of the reinforcing wire, and the diameter or width of the welding strip is smaller than the length of the reinforcing wire.

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