XBC solar cell piece hidden confluence connection structure and photovoltaic module

Abstract

The utility model relates to the solar photovoltaic field, and discloses an XBC solar cell piece hidden type bus connection structure comprising a plurality of XBC solar cell pieces, a bus bar, an insulating film and a plurality of welding strips. Wherein the bus bar is hidden below the XBC solar cells and is electrically connected with all the welding strips on the two cells connected with the bus bar. The insulating film is provided with a plurality of notches used for exposing the welding strip. The insulating film is arranged between the bus bar and the XBC solar cell and used for isolating the portions, except the position where the welding strip is located, of the bus bar from making contact with the cell. The utility model further discloses an XBC solar photovoltaic assembly with the hidden bus bar. Convergence connection between XBC solar cell strings in the assembly is achieved through the connection structure. According to the utility model, on the premise of not influencing the convergence capability of the battery piece, the conversion efficiency of the solar module is improved, and even the sizes of glass and a glue film can be reduced, thereby saving the cost.

Description

Technical Field

[0001] The utility model relates to the field of solar photovoltaics, in particular to an XBC solar cell sheet hidden busbar connection structure and a photovoltaic assembly. Background Art

[0002] With the rapid development of the photovoltaic industry, crystalline silicon solar cells and modules have become a hot topic in research to maximize the benefits of solar cell modules. The production of photovoltaic modules uses welding ribbons to weld single cells into strings, and arranges the welded cell strings in a certain order, and then welds bus bars for current extraction on the head and tail of the cell string.

[0003] Packaging batteries into modules can not only ensure the voltage, current and output power of the batteries, but also protect the batteries from environmental damage and mechanical damage. However, after the crystalline silicon solar cells are packaged into modules, there are some parts on the modules that cannot generate electricity. The larger the area, the greater the power loss of the module packaging. The difference between the power of the module (actual power) and the sum of the power of all the cells (theoretical power) is called the module packaging power loss, and its calculation formula is: module power loss = (theoretical power-actual power) / theoretical power.

[0004] In order to reduce the loss of component packaging, the market now uses backplane gap reflection and reduces the gap between the bus bar and the battery cell, but the glass transparent part caused by the bus bar lead-out is still large. Therefore, how to reduce the glass transparent part has become one of the main research and development directions for reducing component packaging power loss. Utility Model Content

[0005] The purpose of the utility model is to provide an XBC solar cell hidden busbar connection structure and a photovoltaic module, which can effectively reduce the light transmission area of ​​the glass and shorten the creepage clearance without affecting the busbar capacity of the cell, thereby improving the conversion efficiency of the solar cell module, and even reduce the size of the glass and the film, thereby saving costs.

[0006] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0007] The utility model discloses an XBC solar cell hidden busbar connection structure, which comprises a plurality of XBC solar cell sheets, a busbar, an insulating film and a plurality of welding strips; the backs of the XBC solar cell sheets are all provided with mutually staggered positive main grid lines and negative main grid lines; wherein two adjacent XBC solar cell sheets connected for busbar connection are respectively a first XBC solar cell sheet and a second XBC solar cell sheet; the plurality of welding strips are respectively electrically connected one by one with all the positive main grid lines or all the negative main grid lines on the first XBC solar cell sheet, and the plurality of welding strips are respectively electrically connected one by one with all the positive main grid lines or all the negative main grid lines on the second XBC solar cell sheet, wherein the electrodes of the first XBC solar cell sheet electrode main grid lines connected with the welding strips are opposite to those of the second XBC solar cell sheet electrode main grid lines.

[0008] The bus bar is hidden under the XBC solar cell sheet and is electrically connected to all the welding strips on the two solar cells connected to the bus; the insulating film is provided with a plurality of notches for exposing the welding strips; the insulating film is provided between the bus bar and the XBC solar cell sheet and is used to isolate the bus bar from contacting the solar cell sheet except for the position of the welding strip.

[0009] Furthermore, the length of the welding strip is consistent with the electrode main grid line of the battery cell, the width is not less than the width of the battery cell main grid line, and does not exceed the width of the insulating layer on both sides of the main grid line.

[0010] Furthermore, the bus bar is aligned with the upper end or the lower end of the battery cell.

[0011] Furthermore, the XBC solar cell sheet is a whole cell or a cell sheet cut into multiple equal parts.

[0012] Furthermore, the thickness of the insulating film is less than or equal to the thickness of the welding strip and the insulating film is one of an insulating tape or an insulating plastic; the width of the notch on the insulating film is not less than the width of the welding strip. It is ensured that the welding strip can have a good contact with the electrode main grid line, and the insulating film itself has a certain flexibility, which can ensure that the busbar will not crush the battery cell during lamination. However, the width of the notch does not exceed the width of the insulating layer on both sides of the main grid line to prevent the positive and negative electrode thin grid lines crossing the battery cell from touching the busbar and causing a short circuit.

[0013] Furthermore, the distance H between the first welding strip and the end of the bus bar is 2-2.5 mm, and the distance L between the first insulating film notch and the end of the insulating film is 4-4.5 mm.

[0014] The utility model also discloses an XBC solar photovoltaic module with hidden busbars, comprising an upper glass, an upper adhesive film, an XBC solar cell string with a good busbar connection, a lower adhesive film, a lower glass or a lower back plate laminated in sequence. Two adjacent XBC solar cell strings connected for busbar connection are respectively a first XBC solar cell string and a second XBC solar cell string, and the head piece or tail piece of the first XBC solar cell string is connected with the head piece or tail piece of the second XBC solar cell string by adopting the above-mentioned XBC solar cell hidden busbar connection structure.

[0015] Furthermore, the XBC solar cell string includes a plurality of XBC solar cell sheets and welding strips, and the electrode main grid lines of two adjacent XBC solar cell sheets are connected in series via welding strips at the head and tail ends thereof to form a string.

[0016] The benefits of the utility model are:

[0017] The utility model adopts the method of back-connected busbar to replace busbar lead-out welding, which effectively reduces the light-transmitting area of ​​the glass and shortens the creepage clearance. At the same time, an insulating film is provided between the busbar and the battery cell to isolate the busbar from contacting the positive and negative electrode main grid lines on the battery cell to prevent the positive and negative electrodes from converging and causing a short circuit. A number of notches are provided on the insulating film to expose the welding strip, so that the welding strip can be completely fitted with the electrode main grid lines on the battery cell, increasing the length of the connection between the welding strip and the electrode main grid lines, so that the battery cell converging capacity of the utility model is not lower than the converging capacity of the busbar in the prior art in an external form. The battery cell will not be damaged. Since the light-transmitting area of ​​the glass is reduced and the creepage clearance is shortened, the conversion efficiency of the solar module is improved, and even the size of the glass and the film can be reduced, thereby saving costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the hidden bus connection of two adjacent XBC solar cells in this embodiment.

[0019] Figure 2 yes Figure 1 Schematic diagram of the cross section at point A in the middle.

[0020] Figure 3 This is a simplified schematic diagram of an XBC solar cell.

[0021] Figure 4 It is a schematic diagram of the connection between the welding ribbon and the bus bar.

[0022] Figure 5 It is a schematic diagram of the structure of the insulating film.

[0023] Figure 6 It is a schematic diagram of the hidden bus connection of three adjacent XBC solar cell strings in this embodiment.

[0024] Main component symbols:

[0025] 1. XBC solar cell, 11. positive busbar, 12. negative busbar, 13. first XBC solar cell, 14. second XBC solar cell;

[0026] 2. Bus bar;

[0027] 3. Welding strip;

[0028] 4. insulating film, 41. notch;

[0029] 5. XBC solar cell string. DETAILED DESCRIPTION

[0030] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0031] like Figures 1 to 5 As shown, the utility model discloses a hidden busbar connection structure of an XBC solar cell, which includes an XBC solar cell 1, a busbar 2, an insulating film 4 and a plurality of welding strips 3. Among them, the XBC solar cell 1 is a whole cell or a cell cut into multiple equal parts. Preferably, the length of the welding strip 3 is consistent with the electrode main grid line of the cell, so as to maximize the effective area where the welding strip 3 fits the electrode main grid line and improve the busbar capacity. The width of the welding strip 3 is not less than the width of the cell main grid line, and does not exceed the width of the insulating layer on both sides of the main grid line.

[0032] like Figure 3 As shown, the back side of the XBC solar cell 1 is provided with positive busbars 11 and negative busbars 12 that are staggered with each other.

[0033] The two adjacent XBC solar cells connected for convergence are respectively the first XBC solar cell 13 and the second XBC solar cell 14; a plurality of welding strips 3 are respectively and completely attached to and electrically connected with all the positive main grid lines 11 or all the negative main grid lines 12 on the first XBC solar cell 13, and a plurality of welding strips 3 are respectively and completely attached to and electrically connected with all the positive main grid lines 11 or all the negative main grid lines 12 on the second XBC solar cell 14, wherein the electrodes of the electrode main grid lines of the first XBC solar cell 13 connected to the welding strips 3 and the electrode main grid lines of the second XBC solar cell 14 are opposite. Figure 1 The dotted line in the figure is the welding point where the welding strip and the electrode grid line are bonded and welded.

[0034] like Figure 2As shown, the bus bar 2 is hidden under the XBC solar cell and electrically connected to all the welding strips 3 on the two connected bus cells. Preferably, the bus bar 2 is aligned with the upper or lower end of the cell. The distance H between the first welding strip 3 and the end of the bus bar 2 is 2-2.5 mm.

[0035] like Figure 2 , Figure 5 As shown, the insulating film 4 is provided with several notches 41 for exposing the welding strips 3. The insulating film 4 is arranged between the busbar 2 and the XBC solar cell sheet, and is used to isolate the busbar 2 from contacting the cell sheet except for the position of the welding strips 3. Preferably, the thickness of the insulating film 4 is less than or equal to the thickness of the welding strips 3, ensuring that the welding strips 3 can have a good contact with the electrode main grid line. And the insulating film 4 is one of an insulating tape or an insulating plastic, which has a certain flexibility, and can ensure that the busbar 2 will not crush the cell sheet during lamination. The width of the notch 41 on the insulating film 4 is not less than the width of the welding strip 3, which is convenient for the placement and installation of the insulating film 4. However, the width of the notch does not exceed the width of the insulating layer on both sides of the main grid line, preventing the positive and negative electrode fine grid lines of the cell sheet from touching the busbar and causing a short circuit. The distance L between the first notch 41 of the insulating film 4 and the end of the insulating film 4 is preferably 4-4.5mm. The distance L is greater than the distance H, which can achieve a better insulation effect.

[0036] like Figures 1 to 6 As shown, the utility model also discloses an XBC solar photovoltaic module with hidden busbar, comprising an upper glass, an upper adhesive film, an XBC solar cell string 5 with a good busbar connection, a lower adhesive film, a lower glass or a lower back plate laminated in sequence. The two adjacent XBC solar cell strings 5 ​​connected with the busbar are respectively a first XBC solar cell string 5 and a second XBC solar cell string 5. The head piece or tail piece of the first XBC solar cell string 5 is connected with the head piece or tail piece of the second XBC solar cell string 5 by adopting the above-mentioned XBC solar cell hidden busbar connection structure.

[0037] The XBC solar cell string 5 includes a plurality of XBC solar cell sheets 1 and welding strips 3. The electrode main grid lines of two adjacent XBC solar cell sheets are connected in series via the welding strips 3 to form a string.

[0038] like Figures 1 to 6 As shown, the manufacturing method of the XBC solar photovoltaic module with hidden busbars comprises the following steps:

[0039] S1. Make a number of XBC solar cell strings 5: The XBC solar cell strings 5 ​​are welded in series by connecting a number of solar cells and welding ribbons 3 end to end. Two adjacent XBC solar cell strings 5 ​​connected and converged are recorded as: a first XBC solar cell string 5 and a second XBC solar cell string 5.

[0040] S2. Make a combination of busbar 2 and welding strips 3: one end of several welding strips 3 is electrically connected to the busbar 2 at equal intervals, wherein the welding strips 3 correspond one-to-one to the positive main grid lines 11 or the negative main grid lines 12 on the battery cell; the electrical connection between the busbar 2 and the welding strips 3 is fixed by a string welding machine or manual welding; the distance H between the first welding strip 3 and the end of the busbar 2 is 2-2.5mm.

[0041] S3, making insulating film 4: cut an insulating elastic material not smaller than the bus bar 2, and cut a plurality of notches 41 in the insulating elastic material for exposing the welding strip 3; the insulating film 4 is made of insulating tape or insulating plastic; the distance L between the first notch 41 of the insulating film 4 and the end of the insulating film 4 is 4-4.5mm.

[0042] S4, with the insulating film 4, the busbar 2 and the welding strip 3 are combined and electrically connected to two adjacent strings of XBC solar cell strings 5 ​​in sequence: the busbar 2 is located below the cell string and is hidden, the insulating film 4 is placed between the busbar 2 and the cell string and the welding strip 3 is exposed from the notch 41, which is used to isolate the busbar 2 other than the welding strip 3 from contacting the cell. Half of the welding strip 3 is electrically connected to the positive main grid line 11 or the negative main grid line 12 of the head or tail of the first XBC solar cell string 5, and the other half of the welding strip 3 is electrically connected to the positive main grid line 11 or the negative main grid line 12 of the head or tail of the second XBC solar cell string 5, wherein the electrodes of the main grid electrodes of the adjacent cell strings connected to the welding strip 3 are opposite. The electrical connection between the welding strip 3 and the cell is to align the welding strip 3 with the electrode main grid line of the cell first, and place a press to fix it, and then fix the welding strip 3 on the cell by sticking a tape or hot welding, so as to draw out the current of the cell and converge it.

[0043] S5, packaging into components: The packaging is carried out by placing the lower glass or lower backplane, the upper adhesive film, the battery string connected in step S4, the lower adhesive film, and the upper glass in sequence from bottom to top, and sending them into lamination to complete the packaging.

[0044] In summary, the utility model can effectively reduce the light transmission area of ​​the glass and shorten the creepage clearance without affecting the current collection capacity of the battery cell, thereby improving the conversion efficiency of the solar module, and can even reduce the size of the glass and the film, thereby saving costs.

[0045] The above are only preferred specific implementation methods of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by any technician familiar with the technical field within the technical scope disclosed in the present invention should be covered within the protection scope of the present invention.

Claims

1. A XBC solar cell hidden busbar connection structure, comprising a plurality of XBC solar cells, a busbar, an insulating film and a plurality of welding strips; the back of each XBC solar cell is provided with mutually staggered positive busbars and negative busbars; wherein two adjacent XBC solar cells connected to the busbar are respectively a first XBC solar cell and a second XBC solar cell; a plurality of welding strips are respectively electrically connected to all positive busbars or all negative busbars on the first XBC solar cell, and a plurality of welding strips are respectively electrically connected to all positive busbars or all negative busbars on the second XBC solar cell, wherein the electrodes of the first XBC solar cell electrode busbar connected to the welding strips and the second XBC solar cell electrode busbar are opposite; characterized in that: The bus bar is hidden under the XBC solar cell sheet and is electrically connected to all the welding strips on the two solar cells connected to the bus; the insulating film is provided with a plurality of notches for exposing the welding strips; the insulating film is provided between the bus bar and the XBC solar cell sheet and is used to isolate the bus bar from contacting the solar cell sheet except for the position of the welding strip.

2. The XBC solar cell hidden busbar connection structure according to claim 1, characterized in that: The length of the welding strip is consistent with the electrode main grid line of the battery cell, the width is not less than the width of the main grid line of the battery cell, and does not exceed the width of the insulating layer on both sides of the main grid line.

3. The XBC solar cell hidden bus connection structure according to claim 1, characterized in that: The bus bar is aligned with the upper end or the lower end of the battery cell.

4. The XBC solar cell hidden busbar connection structure according to claim 1, characterized in that: The XBC solar cell sheet is a whole cell or a cell sheet cut into multiple equal parts.

5. The XBC solar cell hidden busbar connection structure according to claim 1, characterized in that: The thickness of the insulating film is less than or equal to the thickness of the welding strip; the width of the notch on the insulating film is not less than the width of the welding strip and does not exceed the width of the insulating layer on both sides of the main grid line; the insulating film is one of an insulating tape or an insulating plastic.

6. The XBC solar cell hidden busbar connection structure according to claim 1, characterized in that: The distance H between the first welding strip and the end of the busbar is 2-2.5 mm, and the distance L between the first insulating film notch and the end of the insulating film is 4-4.5 mm.

7. An XBC solar photovoltaic module with hidden busbars, comprising an upper glass, an upper adhesive film, an XBC solar cell string with busbar connections, a lower adhesive film, a lower glass or a lower back sheet laminated in sequence; characterized in that: The two adjacent XBC solar cell strings connected for busing are respectively a first XBC solar cell string and a second XBC solar cell string, and the head piece or tail piece of the first XBC solar cell string is connected with the head piece or tail piece of the second XBC solar cell string by adopting the XBC solar cell hidden busing connection structure according to any one of claims 1 to 6.

8. The XBC solar photovoltaic module with hidden busbars according to claim 7, characterized in that: The XBC solar cell string comprises a plurality of XBC solar cell sheets and welding strips. The electrode main grid lines of two adjacent XBC solar cell sheets are connected in series via welding strips to form a string.

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