Photovoltaic module and bus bar positioning tool

Abstract

The utility model provides a photovoltaic module and a bus bar positioning tool. The photovoltaic module comprises bus bars which are located on the edges of the battery strings and fall into the coverage range of the battery pieces at the ends, insulating strips are arranged between the bus bars and the battery pieces, and the bus bars are electrically connected with the battery pieces at the ends of the battery strings through welding strips. According to the photovoltaic module provided by the technical scheme of the utility model, the bus bar is fixed to the back surface of the battery piece in a Z shape or a straight line shape, and the welding strip is directly welded to the bus bar, so that the problems of local overheating and resistance increase of the welding strip caused by welding strip folding are avoided, the fire risk is reduced, and the power generation efficiency of the module is improved; the welding strip is welded to the back bus bar of the battery piece, so that the creepage distance can be reduced, a narrow-edge assembly is obtained, the attractiveness of the assembly is improved, and meanwhile the efficiency of the assembly is maximized. The bus bar positioning tool provided by the invention can be well matched with the photovoltaic module, and is favorable for improving the production efficiency of the photovoltaic module and ensuring the production quality of the photovoltaic module.

Description

Technical Field

[0001] The present application relates to the field of photovoltaic cell technology, and in particular to a photovoltaic module and busbar positioning tool. Background Art

[0002] As modern society places increasing demands on the aesthetics of photovoltaic modules, designs tend to reduce white space in order to maximize the use of module size and improve overall efficiency. However, in traditional photovoltaic module designs, due to the presence of busbars, the distance between the cell and the edge of the module has to be increased to meet the regulatory requirements for creepage distance. This practice results in too much white space in the module, which not only affects the aesthetics of the photovoltaic module, but also reduces the effective area of ​​the module, thereby reducing the power generation efficiency of the module. Therefore, how to reduce white space has become a technical problem that needs to be solved in the current field of photovoltaic module design. Utility Model Content

[0003] The purpose of the present application is to provide a photovoltaic module and busbar positioning tool, wherein the busbar of the photovoltaic module is fixed to the back of the battery cell, effectively avoiding the problems of local overheating and increased resistance caused by folding of the welding ribbon.

[0004] In a first aspect, the present application provides a photovoltaic module, comprising a plurality of battery strings, and at least comprising a first battery string and a second battery string arranged in parallel along a first direction, each battery string comprising a plurality of battery cells sequentially connected in series along a second direction, and a welding strip for connecting the battery cells in series along the second direction;

[0005] It also includes a bus bar located at the edge of the battery string and falling within the coverage of the battery sheet at the end, the bus bar includes a first bus bar and a second bus bar connected in sequence, and an insulating strip is arranged between the bus bar and the battery sheet;

[0006] The bus bar is electrically connected to the end battery cell of each battery string through the welding strip, and the extending direction of the welding strip is always in the same direction as the second direction;

[0007] A positive pole grid line is arranged on the back of the battery string, and a negative pole grid line is arranged on the front of the battery string;

[0008] The positive grid line on the back side of the first battery string covers the insulating strip, and the first bus bar is arranged on the insulating strip and electrically connected to the positive grid line;

[0009] The negative pole grid line on the front side of the second battery string covers the insulating strip, and the second bus bar is arranged on the insulating strip and electrically connected to the negative pole grid line;

[0010] The bus bar passes through the gap between the first battery string and the second battery string from the back side of the first battery string to the front side of the second battery string, and is respectively connected to the positive grid line and the negative grid line to connect the first battery string and the second battery string in series;

[0011] The first direction and the second direction are perpendicular to each other.

[0012] In an implementable solution, there is an inter-group spacing D between the first battery string and the second battery string, and the inter-group spacing is between 10 mm and 30 mm.

[0013] In an practicable solution, the bus bar has a first edge close to the end of the battery cell where the bus bar is arranged, and a second edge away from the end of the battery cell;

[0014] There is a distance between the second edge and the end of the battery cell, and the distance is between 0 mm and 20 mm.

[0015] In an operative solution, the insulating strip has a first insulating edge close to the end of the battery cell where the insulating strip is disposed, and a second insulating edge away from the end of the battery cell;

[0016] There is a distance between the second insulating edge and the end of the battery cell, and the distance is between 0 mm and 20 mm; the first insulating edge overlaps with the first edge of the bus bar.

[0017] In one feasible solution, the busbar is a flexible busbar.

[0018] In an implementable solution, the thickness of the insulating strip is between 0.01 mm and 0.1 mm; the thickness of the bus bar is between 0.05 mm and 0.2 mm; and the thickness of the battery cell is between 0.1 mm and 0.2 mm.

[0019] In a second aspect, the present application provides a busbar positioning tool for installing a busbar of a photovoltaic module, wherein the photovoltaic module includes a first battery string and a second battery string arranged in parallel, and the busbar positioning tool includes a base and further includes:

[0020] A barrier portion, disposed on the surface of the base and abutting against the end of the photovoltaic assembly to position the first battery string and the second battery string;

[0021] At least one pressing portion is arranged on the barrier portion, the first battery string abuts against the barrier portion and the end of the first battery string close to the second battery string is located below the pressing portion, and the pressing portion is used to press and position the bus bar and the end of the first battery string.

[0022] In an implementable solution, the pressing portion includes a pressing plate, and a plurality of elastic members are arranged on the bottom surface of the pressing plate; when the first battery string and the bus bar enter under the pressing portion and are located at the welding operation position, the bus bar is pressed to fit tightly and fix to the first battery string.

[0023] In an implementable solution, the holding portion further includes a buffer block, which is disposed below a plurality of the elastic members and connected to each of the elastic members.

[0024] In an implementable solution, one end of the buffer block away from the blocking portion has an arc transition surface.

[0025] In an implementable solution, the position of the pressing portion on the blocking portion can be adjusted along the length direction of the blocking portion.

[0026] In an implementable solution, the busbar positioning tool is used to install the busbar of the photovoltaic module as described in any of the above technical solutions.

[0027] Compared with the prior art, the beneficial effects of the technical solution of this application include at least the following aspects:

[0028] The photovoltaic module provided by the technical solution of this application fixes the busbar to the back of the battery cell in a "Z" shape, and the welding strip is directly welded to the busbar, avoiding the problem of local overheating and increased resistance of the welding strip caused by folding the welding strip, reducing the risk of fire and improving the power generation efficiency of the module; welding the welding strip to the busbar on the back of the battery cell can reduce the creepage distance, thereby obtaining a narrow-edge module, improving the aesthetics of the module while maximizing the efficiency of the module. The busbar positioning tool provided by this application can be well adapted to the above-mentioned photovoltaic module, which is conducive to improving the production efficiency of the photovoltaic module and ensuring its production quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0030] Figure 1 It is a schematic diagram of the structure of a photovoltaic module in the prior art.

[0031] Figure 2 A schematic diagram of the partial structure of a photovoltaic module provided in one embodiment of the present application.

[0032] Figure 3A schematic diagram of the structure of a narrow-edge photovoltaic module with grid lines on both the front and back sides provided in an embodiment of the present application.

[0033] Figure 4 A schematic diagram of the partial structure of a photovoltaic module provided in another embodiment of the present application.

[0034] Figure 5 A schematic diagram of the structure of a narrow-edge photovoltaic module in which all grid lines are present on the back side according to another embodiment of the present application.

[0035] Figure 6 Schematic diagram of the relative position relationship between the cross section of the bus bar and the battery cell.

[0036] Figure 7 A schematic diagram of the internal structure of the busbar positioning tool provided in this application.

[0037] Figure 8 A schematic diagram of the top structure of the busbar positioning tool provided in this application.

[0038] In the figure:

[0039] 10. Photovoltaic module; 11. First battery string; 12. Second battery string; 13. Welding strip; 14. Bus bar; 141. First edge; 142. Second edge; 15. Insulating strip; 151. First insulating edge; 152. Second insulating edge; 16. Positive grid line; 17. Negative grid line;

[0040] 20. Positioning tool; 21. Blocking part; 22. Holding part; 221. Pressing plate; 222. Elastic member; 23. Buffer block. DETAILED DESCRIPTION

[0041] Existing technologies such as Figure 1 As shown, the setting of the busbar 14 significantly increases the distance from the edge of the battery cell to the edge of the module. Although it meets the creepage distance requirements in the safety specifications, it sacrifices the aesthetics and efficiency of the module. In order to solve this problem, existing technologies have proposed improvement schemes, such as a foldable busbar, circuit connection structure and shingled assembly disclosed in Chinese patent CN202010321149.5, and a battery pack structure, photovoltaic module and production method proposed in Chinese patent CN201811468415.6. Both patents attempt to shorten the creepage distance by folding the welding strip from the front to the back of the battery cell, thereby reducing the blank space and improving the efficiency of the photovoltaic module.

[0042] However, although the above scheme can effectively reduce the blank space and improve efficiency in theory, it faces new problems in practical applications. The welding ribbon is prone to folding at the folding position during the folding process. This folding may not only cause local overheating of the welding ribbon, but also increase resistance, affect the current transmission efficiency, and thus have an adverse effect on the overall performance of the photovoltaic module. Therefore, how to reduce the blank space while avoiding the problems caused by the folding of the welding ribbon has become a technical problem that needs to be solved urgently in the current photovoltaic module design field. In view of this, the present application provides a photovoltaic module and busbar positioning tooling.

[0043] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0044] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0045] The present application provides a photovoltaic module and busbar positioning tool, wherein the busbar 14 of the photovoltaic module is fixed to the back of the battery cell, effectively avoiding the problem of local overheating and increased resistance caused by the folding of the welding ribbon 13. Figures 2 to 5 As shown, the photovoltaic module includes a plurality of cell strings, welding ribbons 13 , bus bars 14 and insulating strips 15 .

[0046] The battery string at least includes a first battery string 11 and a second battery string 12 arranged in parallel along a first direction, each battery string includes a plurality of battery cells sequentially connected in series along a second direction, and a welding strip 13 for connecting the battery cells in series along the second direction;

[0047] The bus bar 14 is located at the edge of the battery string and falls within the coverage range of the end battery cell, and an insulating strip 15 is arranged between the bus bar 14 and the battery cell; the bus bar 14 is electrically connected to the end battery cell of each battery string through the welding strip 13, and the extension direction of the welding strip 13 is always in the same direction as the second direction; the first direction is perpendicular to the second direction.

[0048] In an optional embodiment, Figure 2 and Figure 3As shown, there is an inter-group spacing D between the first battery string 11 and the second battery string 12, and the inter-group spacing is between 10mm and 30mm. At least two battery strings are connected in series to meet the voltage and power requirements of the photovoltaic module; a certain spacing can avoid short circuits between battery cells, and appropriate spacing can make the battery panel more neat and orderly, thereby improving its overall aesthetics. Further, the inter-group spacing is between 15mm and 35mm.

[0049] In an optional embodiment, the bus bar 14 has a first edge 141 close to the end of the battery cell on which it is arranged, and a second edge 142 away from the end of the battery cell; the second edge 142 has a distance from the end of the battery cell, and the distance is between 0mm and 20mm.

[0050] In an optional embodiment, the insulating strip 15 has a first insulating edge 151 close to the end of the battery sheet where it is arranged, and a second insulating edge 152 away from the end of the battery sheet;

[0051] The second insulating edge 152 has a spacing with the end of the battery cell, and the spacing is between 0mm and 20mm; the first insulating edge 151 coincides with the first edge 141 of the busbar 14. If the size of the insulating strip 15 is smaller than the size of the busbar 14, a short circuit will occur. As an example, the size of the battery cell used in the technical solution of the present application is: length 182*width 91*thickness 0.16mm, the length and width of the insulating strip 15 are determined according to the length and width of the busbar 14, and it is better to increase the length and width of the busbar 14 by 10mm respectively. The thickness of the insulating strip is preferably 0.02mm, and the insulating strip 15 is close to the edge of the battery.

[0052] In an optional implementation scheme, the thickness of the insulating strip 15 is between 0.01 mm and 0.1 mm; the thickness of the bus bar 14 is between 0.05 mm and 0.2 mm; and the thickness of the battery cell is between 0.1 mm and 0.2 mm.

[0053] In one embodiment, if Figure 2 and Figure 3 As shown, a positive electrode grid line 16 is arranged on the back of the battery string, and a negative electrode grid line 17 is arranged on the front of the battery string;

[0054] The positive grid line 16 on the back side of the first battery string 11 covers the insulating strip 15, and the first bus bar is disposed on the insulating strip 15 and electrically connected to the positive grid line 16;

[0055] The negative grid line 17 on the front side of the second battery string 12 covers the insulating strip 15, and the second bus bar is disposed on the insulating strip 15 and is electrically connected to the negative grid line 17;

[0056] Among them, Figure 6As shown, the first bus bar and the second bus bar are the same bus bar 14, and the bus bar 14 passes through the gap between the first battery string 11 and the second battery string 12 from the back of the first battery string 11 to the front of the second battery string 12, and is respectively connected to the positive grid line 16 and the negative grid line 17 to connect the first battery string 11 and the second battery string 12 in series. Further, the bus bar 14 is a flexible bus bar, and the flexible bus bar usually uses staggered copper strands or silver-impregnated copper wires as the conductive body to meet the requirements of the flexible bus bar for current transmission and flexibility. The arrangement and number of copper strands or silver-impregnated copper wires are adjusted according to the specifications of the flexible bus bar and the current transmission requirements of the photovoltaic panel, and no further details are given here. For the battery cell with grid lines on both the front and back sides, the bus bar 14 is fixed to the back of the battery cell in a "Z" shape, and the welding strip 13 is welded to the bus bar 14, which well avoids the problem of local overheating and increased resistance of the welding strip caused by the folding of the welding strip 13.

[0057] Figure 3 is a schematic diagram of the structure of a narrow-edge photovoltaic module with grid lines on both the front and back sides in the above technical solution. Figure 1 ) Due to the presence of the busbar 14, the distance from the cell to the glass edge is relatively large, usually 20.4 mm. Figure 3 In the narrow-edge photovoltaic module shown, the distance from the cell to the glass edge is only 10.4 mm, which meets the creepage requirements while reducing the blank edge.

[0058] In one embodiment, if Figure 4 and Figure 5 As shown, a positive electrode grid line 16 is disposed on the back of the first battery string 11; a negative electrode grid line 17 is disposed on the back of the second battery string 12;

[0059] The positive grid lines 16 on the back of the first battery string 11 and the positive grid lines 16 on the back of the second battery string 12 are both covered with insulating strips 15, and the busbars 14 are arranged on the insulating strips 15 and are electrically connected to the positive grid lines 16 of the first battery string 11 and the negative grid lines 17 of the second battery string 12, respectively, so as to connect the first battery string 11 and the second battery string 12 in series, and the busbars are flexible busbars. For battery cells without grid lines on the front, the busbars are fixed in a "one" shape on the back of the battery cell, and the welding strips 13 are welded to the busbars 14 on the back of the battery cell to avoid the problem of local overheating and increased resistance of the welding strips 13 caused by the folding of the welding strips 13. Figure 5 is a schematic diagram of the structure of a narrow-edge photovoltaic module in which all grid lines are present on the back in the above technical solution. Figure 1 As shown in the figure, due to the presence of the busbar 14, the distance between the cell and the edge of the glass is relatively large, usually 20.4 mm. Figure 5 In the narrow-edge photovoltaic module shown, the distance from the cell to the glass edge is only 10.4 mm, which meets the creepage requirements while reducing the blank edge.

[0060] In one embodiment, the present application also provides a busbar positioning tool, such as Figure 7 and Figure 8 As shown, the busbar positioning tool includes a baffle 21 and at least one pressing portion 22 arranged on the surface of the base. It can be understood that the base can be a plate with a planar structure, independent of the operating platform of the photovoltaic module; the base can also be the operating platform of the photovoltaic module, and the baffle 21 is installed on the operating platform to form an integral structure with the operating platform. Specifically:

[0061] The barrier 21 abuts against the end of the photovoltaic module 10 to position the first battery string 11 and the second battery string 12; the pressing portion 22 is arranged on the barrier 21, the first battery string 11 abuts against the barrier 21 and the end of the first battery string 11 close to the second battery string 12 is located below the pressing portion 22, and the pressing portion 22 is used to press and position the bus bar 14 with the end of the first battery string 11. Furthermore, since the gap between the two first battery strings 11 and the second battery string 12 is the main reason for the bending, loose attachment or warping of the flexible bus bar 14, the clamping position of the pressing portion 22 in the first battery string 11 is relatively close to the gap between the two battery strings, but not clamped at the corners of the first battery string 11 to avoid damage to the battery cells.

[0062] In an optional embodiment, if Figure 7 and Figure 8 As shown, the pressing part 22 includes a pressing plate 221, and a plurality of elastic members 222 are arranged on the bottom surface of the pressing plate 221; when the first battery string 11 and the bus bar 14 enter the bottom of the pressing part 22 and are located at the welding operation position, the bus bar 14 is pressed and tightly fit and fixed to the first battery string 11. In order to adapt to more application scenarios and bus bar welding requirements of photovoltaic modules of different sizes, the position of the pressing part 22 on the baffle 21 can be adjusted along the length direction of the baffle 21, so as to accurately position and fix the bus bar 14.

[0063] In an optional embodiment, if Figure 7 and Figure 8 As shown, the pressing portion 22 further includes a buffer block 23, which is disposed below a plurality of elastic members 222 and connected to each elastic member 222. Preferably, the elastic member 222 is a compression spring, and further, the number of the elastic members 222 is at least two to achieve balanced pressure.

[0064] In an optional embodiment, if Figure 7 and Figure 8 As shown, the end of the buffer block 23 away from the barrier portion 21 has an arc transition surface, which prevents the tooling from causing collision damage to the edge of the battery cell when the battery cell approaches the tooling.

[0065] The above description is only a partial embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A photovoltaic module, comprising a plurality of battery strings, and at least comprising a first battery string (11) and a second battery string (12) arranged in parallel along a first direction, each battery string comprising a plurality of battery cells sequentially connected in series along a second direction, and a welding strip (13) for connecting the battery cells in series along the second direction; characterized in that: It also includes a bus bar (14) located at the edge of the battery string and falling within the coverage of the battery slice at the end, the bus bar (14) including a first bus bar and a second bus bar connected in sequence, and an insulating strip (15) is provided between the bus bar (14) and the battery slice; the bus bar (14) is electrically connected to the end battery slice of each battery string through the welding strip (13), and the extension direction of the welding strip (13) is always in the same direction as the second direction; A positive electrode grid line (16) is arranged on the back of the battery string, and a negative electrode grid line (17) is arranged on the front of the battery string; The positive grid line (16) on the back side of the first battery string (11) covers the insulating strip (15), and the first bus bar is arranged on the insulating strip (15) and is electrically connected to the positive grid line (16); The negative electrode grid line (17) on the front side of the second battery string (12) covers the insulating strip (15), and the second bus bar is arranged on the insulating strip (15) and is electrically connected to the negative electrode grid line (17); The bus bar (14) extends from the back side of the first battery string (11) through the gap between the first battery string (11) and the second battery string (12) to the front side of the second battery string (12), and is respectively connected to the positive electrode grid line (16) and the negative electrode grid line (17) to connect the first battery string (11) and the second battery string (12) in series; The first direction and the second direction are perpendicular to each other.

2. The photovoltaic module according to claim 1, characterized in that: There is an inter-group spacing D between the first battery string (11) and the second battery string (12), and the inter-group spacing D is between 10 mm and 30 mm.

3. The photovoltaic module according to claim 1, characterized in that: The bus bar (14) has a first edge (141) close to the end of the battery cell on which it is arranged, and a second edge (142) away from the end of the battery cell; There is a distance between the second edge (142) and the end of the battery sheet, and the distance is between 0 mm and 20 mm.

4. The photovoltaic module according to claim 3, characterized in that: The insulating strip (15) has a first insulating edge (151) close to the end of the battery slice on which it is arranged, and a second insulating edge (152) away from the end of the battery slice; The second insulating edge (152) has a distance from the end of the battery cell, the distance being between 0 mm and 20 mm; the first insulating edge (151) overlaps with the first edge (141) of the bus bar (14).

5. The photovoltaic module according to claim 1, characterized in that: The bus bar (14) is a flexible bus bar.

6. The photovoltaic module according to claim 1, characterized in that: The thickness of the insulating strip (15) is between 0.01 mm and 0.1 mm; the thickness of the bus bar (14) is between 0.05 mm and 0.2 mm; and the thickness of the battery cell is between 0.1 mm and 0.2 mm.

7. A busbar positioning tool for installing a busbar of a photovoltaic module according to any one of claims 1 to 6, wherein the photovoltaic module comprises a first battery string (11) and a second battery string (12) arranged in parallel, the busbar positioning tool comprising a base, characterized in that: Also includes: A barrier portion (21) is arranged on the surface of the base and abuts against the end of the photovoltaic assembly to position the first battery string (11) and the second battery string (12); At least one pressing portion (22) is arranged on the barrier portion (21), the first battery string (11) abuts against the barrier portion (21), and an end of the first battery string (11) close to the second battery string (12) is located below the pressing portion (22), and the pressing portion (22) is used to press and position the bus bar and the end of the first battery string (11).

8. The busbar positioning tool according to claim 7, characterized in that: The pressing portion (22) comprises a pressing plate (221), and a plurality of elastic members (222) are arranged on the bottom surface of the pressing plate; when the first battery string (11) and the bus bar (14) enter below the pressing portion (22) and are located at the welding operation position, the bus bar (14) is pressed to be tightly fitted and fixed to the first battery string (11).

9. The busbar positioning tool according to claim 8, characterized in that: The pressing portion further comprises a buffer block (23), which is arranged below a plurality of the elastic members (222) and connected to each of the elastic members (222).

10. The busbar positioning tool according to claim 9, characterized in that: One end of the buffer block (23) away from the blocking portion (21) has an arc transition surface.

11. The busbar positioning tool according to claim 7, characterized in that: The position of the pressing portion (22) on the blocking portion (21) can be adjusted along the length direction of the blocking portion (21).

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