Back contact battery double-glass assembly

Abstract

The utility model relates to the technical field of photovoltaic cells, and discloses a double-glass assembly of a back contact cell, which comprises a cell layer, and a front adhesive film and front glass are sequentially arranged on the front surface of the cell layer; a shielding adhesive film, a conductive layer, a back adhesive film and back glass are sequentially arranged on the back of the battery piece; the battery piece layer comprises a plurality of battery pieces arranged according to a designed circuit; the shielding adhesive film is provided with a plurality of holes, and the positions of the holes correspond to the positions of the electrodes on the battery piece. The conductive layer passes through the opening and is connected with the electrode. According to the utility model, the processes of integral typesetting, isolation shielding, welding and the like are adopted, the precision required for equipment is lower, the process yield can be improved, and the manufacturing cost can be reduced; an integrated adhesive film laying process is adopted, and compared with a shielding method adopted between strings in the prior art, the laying process is simpler, and the cost is lower; meanwhile, the shielding adhesive film is integrally laid, the color is more uniform, shielding chromatic aberration does not exist, the appearance is more attractive, and the shielding adhesive film is particularly suitable for scenes with high appearance requirements.

Description

Technical Field

[0001] This utility model relates to the field of photovoltaic cell technology, and more specifically, to a back-contact double-glass module. Background Technology

[0002] With the development of the photovoltaic industry, back-contact solar cells have begun to be widely used. Back-contact solar cells have no main grid lines or even any electrode patterns on the front side. Both the positive and negative electrodes are located on the back of the cell, which reduces shading, increases the short-circuit current, improves the energy conversion efficiency, and makes the cell more aesthetically pleasing.

[0003] The gridless back-contact solar cell module mainly adopts a lamination welding method for interconnecting solar cells. This involves first printing solder paste, insulating adhesive, and curing adhesive sequentially onto the solar cells, then pre-fixing the solder ribbons onto the cells, and finally welding the solder ribbons to the grid during the lamination process. The disadvantages of this interconnection method are low yield, poor reliability, complex technology, and high precision requirements for equipment.

[0004] When back-contact battery modules are used in all-black modules for distributed villas, the appearance requirements are extremely high. Existing back-contact modules usually use the method of adding isolation shielding strips between the battery cells to shield the solder ribbons or busbars. On the one hand, with the current half-cell 72-cell process, at least 144 isolation strips are required, which is a large number and the process is complicated. On the other hand, the isolation strips and the encapsulation film are usually from different suppliers, resulting in color differences and overlapping edge marks. Existing standards do not regulate this type of appearance.

[0005] Therefore, it is necessary to propose a back-contact battery double-glass module to at least partially solve the problems existing in the prior art. Utility Model Content

[0006] The utility model description section introduces a series of simplified concepts, which will be further explained in detail in the detailed description section. This utility model description section is not intended to limit the key features and essential technical features of the claimed technical solution, nor is it intended to determine the scope of protection of the claimed technical solution.

[0007] To address the aforementioned problems, this utility model discloses a back-contact battery double-glass assembly; it includes:

[0008] The battery cell layer has a front adhesive film and a front glass layer arranged sequentially on the front side; a shielding adhesive film, a conductive layer, a back adhesive film, and a back glass layer arranged sequentially on the back side; the battery cell layer includes multiple battery cells arranged according to the designed circuit; the shielding adhesive film has multiple openings, the positions of which correspond to the positions of the electrodes on the battery cells; the conductive layer passes through the openings and connects to the electrodes.

[0009] Preferably, the electrodes on the battery cell are centered relative to the opening, the width of the opening is greater than the width of the electrode, and the difference is set to 3-5 mm.

[0010] Preferably, the width of the shielding film is equal to the width of the front glass and the back glass, and the thickness of the shielding film is set to 0.2 to 0.25 mm.

[0011] Preferably, the shielding film is any one of EVA film, EPE film, or POE film.

[0012] Preferably, a positive electrode and a negative electrode are provided on the back of the battery cell, and the positive electrode and the negative electrode are located on the lateral sides of the battery cell respectively; the positive electrodes and negative electrodes of adjacent battery cells are arranged alternately in the lateral and longitudinal directions, and the battery cells in the lateral direction can be symmetrically arranged into two groups.

[0013] Preferably, the back-contact double-glass module further includes a positioning tape, with both ends of the positioning tape connected to adjacent cells in the longitudinal direction, and the connection point being the midpoint of the edge of the cell. The positioning tape is set as a high-temperature photovoltaic tape.

[0014] Preferably, the positioning tape is spaced apart along the transverse direction of each column of battery cells.

[0015] Preferably, the conductive layer includes a solder strip connected between the electrodes of the horizontally arranged solar cells. The two ends of the solder strip correspond to the positive electrode of the preceding solar cell and the negative electrode of the following solar cell, respectively. The horizontally arranged solar cells are welded to form a battery string.

[0016] Preferably, the conductive layer further includes a middle busbar, a head busbar, and a tail busbar. The middle busbar is connected to the solder strip between the two sets of transverse battery cell electrodes; the head busbar is welded to the electrode at the transverse head of the battery cell; and the tail busbar is welded to the electrode at the transverse tail of the battery cell.

[0017] Preferably, the middle busbar is connected to the lead wire, and the back film is provided with a back film opening corresponding to the lead wire; the back glass is provided with a back glass opening corresponding to the lead wire.

[0018] Compared with the prior art, the present invention has at least the following beneficial effects:

[0019] The double-glass back-contact battery module provided in this embodiment adopts processes such as overall layout, isolation and shielding, and welding. Compared with other back-contact module packaging processes, it is simpler and requires lower precision from equipment, which can improve the process yield and further reduce the manufacturing cost of the back-contact module.

[0020] This embodiment provides a back-contact battery double-glass module, which, compared to current back-contact white, all-black, or other colored modules, adopts an integrated film laying process. Compared to the existing string-to-string shielding method, the laying process is simpler and less costly. At the same time, the shielding film is laid as a whole, resulting in more uniform color, no shielding color difference, and a more aesthetically pleasing appearance, making it particularly suitable for scenarios with high appearance requirements.

[0021] The present invention relates to a double-glass back-contact battery assembly. Other advantages, objectives and features of the present invention will be partly apparent from the following description, and partly understood by those skilled in the art through study and practice of the present invention. Attached Figure Description

[0022] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0023] Figure 1 This is a cross-sectional structural diagram of the present invention;

[0024] Figure 2 This is a schematic diagram showing the placement of the entire battery cell on the platform in this utility model;

[0025] Figure 3 This is a schematic diagram of the battery cell arrangement structure in step 1 of this utility model;

[0026] Figure 4 This is a schematic diagram of the adhesive tape pasting structure in step 2 of this utility model;

[0027] Figure 5 This is a schematic diagram of the opening structure of the shielding film in step 3 of this utility model;

[0028] Figure 6 This is a schematic diagram of the shielding film laying structure in step 4 of this utility model;

[0029] Figure 7 This is a schematic diagram of the battery cell welding series connection in step 5 of this utility model;

[0030] Figure 8 This is a schematic diagram of the busbar welding series connection in step 6 of this utility model;

[0031] Figure 9 This is a schematic diagram of the structure for laying the back adhesive film in step 7 of this utility model;

[0032] Figure 10 This is a schematic diagram of the back glass laying structure in step 8 of this utility model;

[0033] Figure 11 This is a schematic diagram of the front adhesive film and front glass laying structure in step 10 of this utility model;

[0034] Figure 12 This is a schematic diagram of the arrangement structure of the half-cell battery in this utility model;

[0035] Figure 13 This is a schematic diagram of the welding structure of a half-cell battery in this utility model.

[0036] In the diagram: 1. Battery cell; 2. Front encapsulant film; 3. Front glass; 4. Shielding encapsulant film; 5. Conductive layer; 6. Back encapsulant film; 7. Back glass; 8. Opening; 9. Positive electrode; 10. Negative electrode; 11. Positioning tape; 12. Solder ribbon; 13. Middle busbar; 14. Head busbar; 15. Tail busbar; 16. Back film opening; 17. Back glass opening. Detailed Implementation

[0037] The technical solution of this utility model will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0038] Example

[0039] The present invention will now be further described with reference to the accompanying drawings.

[0040] like Figures 1-11 As shown, this embodiment provides a back-contact battery double-glass module, comprising:

[0041] The battery cell layer has a front adhesive film 2 and a front glass 3 arranged sequentially on the front side; a shielding adhesive film 4, a conductive layer 5, a back adhesive film 6, and a back glass 7 arranged sequentially on the back side; the battery cell layer includes multiple battery cells 1 arranged according to the designed circuit; the shielding adhesive film 4 has multiple openings 8, the positions of which correspond to the positions of the electrodes on the battery cells 1; the conductive layer 5 passes through the openings 8 and connects to the electrodes.

[0042] In this arrangement, the electrode on the battery cell 1 is centered relative to the opening 8, and the width of the opening 8 is greater than the width of the electrode, with the difference set to 3-5 mm.

[0043] The width of the shielding film 4 is equal to the width of the front glass 3 and the back glass 7, and the thickness of the shielding film 4 is set to 0.2 to 0.25 mm.

[0044] Among them, the shielding film 4 is set to any one of EVA film, EPE film, and POE film.

[0045] The back of the battery cell 1 is provided with a positive electrode 9 and a negative electrode 10, which are located on the lateral sides of the battery cell 1 respectively. The positive electrodes 9 and negative electrodes 10 of adjacent battery cells 1 are arranged alternately in the lateral and longitudinal directions, and the battery cells 1 in the lateral direction can be symmetrically arranged into two groups.

[0046] The back-contact double-glass module further includes a positioning tape 11, with both ends of the positioning tape 11 connected to the adjacent solar cells 1 in the longitudinal direction, and the connection point being the midpoint of the edge of the solar cell 1. The positioning tape 11 is set as a high-temperature photovoltaic tape.

[0047] The positioning tape 11 is spaced apart along the transverse direction of each column of the battery cell 1.

[0048] The conductive layer 5 includes a solder strip 12, which is connected between the electrodes of the horizontal solar cell 1. The two ends of the solder strip 12 correspond to the positive electrode 9 of the previous solar cell 1 and the negative electrode 10 of the next solar cell 1, respectively. The horizontal solar cells 1 are welded to form a battery string.

[0049] The conductive layer 5 also includes a middle busbar 13, a head busbar 14, and a tail busbar 15. The middle busbar 13 is connected to the solder strip 12 between the electrodes of the two sets of transverse battery cells 1; the head busbar 14 is welded to the electrode at the transverse head of the battery cell 1; and the tail busbar 15 is welded to the electrode at the transverse tail of the battery cell 1.

[0050] The central busbar 13 is connected to a lead wire, and the back film 6 is provided with a back film opening 16 corresponding to the lead wire; the back glass 7 is provided with a back glass opening 17 corresponding to the lead wire.

[0051] The working principle and beneficial effects of this utility model are as follows:

[0052] This embodiment provides a back-contact battery double-glass module, which is encapsulated according to the following steps:

[0053] Step 1: Place the battery cell 1 with the back facing up on the platform according to the designed circuit and cell spacing; where:

[0054] The platform is equipped with vacuum holes to enable vacuum adsorption, which helps to adhere and fix the placed battery cells 1. A protective non-stick material (such as PTFE cloth) must be affixed to the platform surface, and the vacuum holes on the PTFE cloth must be aligned with the vacuum holes on the platform. The non-stick material protects the front side of the battery cells 1. Simultaneously, the platform has a 180° rotation function, allowing it to rotate 180° to the back side when the back side of the module is stacked, thus enabling the stacking of the front side materials.

[0055] The battery cell 1 is a back contact battery cell, with both positive and negative electrodes located on the back side. In this example, a back contact battery cell with three points is used, with three positive electrodes 9 on one side and three negative electrodes 10 on the other side. The battery cell 1 is a whole battery cell with a size of 125×125mm.

[0056] The battery cells 1 can be arranged manually or automatically by a robot. The horizontal and vertical spacing between battery cells 1 is set to 1-3 mm; the spacing between the two symmetrical groups is set to 10-15 mm; and the distance between the edge battery cells 1 and the surrounding area is determined according to the pattern design.

[0057] The electrode sequence between the solar cells 1 is arranged horizontally as positive-negative-positive-negative or negative-positive-negative-positive. The number of solar cells 1 arranged is 4 to 12. They can be arranged in a single string or in a symmetrical design to form two strings in parallel. The electrodes of the solar cells 1 in the vertical direction are also arranged as positive-negative-positive-negative or negative-positive-negative-positive.

[0058] Step 2: Use positioning tape 11 to attach and fix the vertical solar cells 1 to each other. The positioning tape 11 is a high-temperature photovoltaic tape with UV resistance. The amount of positioning tape 11 attached depends on the size of the panel. The positioning tape 11 can be attached to each row of solar cells 1 or to the solar cells 1 in alternate rows.

[0059] Step 3: After attaching the positioning tape 11, cover the surface of the battery cell 1 with a layer of shielding film 4, wherein:

[0060] The shielding film 4 needs to be cut open at the electrode welding position of the solar cell 1 to form an opening 8. The size, position and data of the opening 8 are determined according to the number and type of solar cell 1. Considering that the laying accuracy of the existing equipment is about ±1mm, and to be compatible with the welding deviation between the photovoltaic ribbon and the electrode during welding (the existing welding deviation is ±0.3~0.5mm), the width of the opening 8 is set to the electrode width + 3~5mm. The main reason is to take into account the accuracy of the process laying.

[0061] The width of the shielding film 4 is consistent with the width of the front glass 3 and the back glass 7 of the module. The thickness of the shielding film 4 is 1 / 2 or 1 / 3 of the thickness of the conventional film, and the thickness is set to 0.2 to 0.25 mm. The shielding film 4 mainly plays the role of shielding and blocking.

[0062] The shielding film 4 can be white, black, or other colors that meet aesthetic requirements;

[0063] The material of the shielding film 4 can be EVA / EPE / POE or other photovoltaic module encapsulation films;

[0064] Step 4: Evenly lay the perforated shielding film 4 on the back of the battery cell 1 in a centered position. The electrode position of the battery cell 1 should be centered at the center of the opening 8 on the shielding film 4.

[0065] Step 5: Select appropriate solder ribbon 12 to perform series welding on adjacent horizontally connected battery cells 1. The positive electrode 9 of the previous battery cell 1 corresponds to the negative electrode 10 of the next battery cell 1, thus realizing the series connection between battery cells 1. In this example, there are 8 battery strings connected in series.

[0066] The series connection between the battery cells 1 can be achieved by welding with solder strip 12, or by fixing with solder strip and conductive adhesive; the solder strip 12 can be a round solder strip or a flat solder strip.

[0067] Step 6: Perform busbar soldering on the connected battery strings:

[0068] Among them, the middle bus bar 13 connects two horizontal battery strings. The middle bus bar 13 is usually a conventional silver bus bar and mainly serves as a bus bar. The head bus bar 14 connects to the head of the battery string, and the tail bus bar 15 connects to the tail of the battery string. The head bus bar 14 and the tail bus bar 15 are usually conventional silver bus bars and mainly serve as series connections.

[0069] Step 7: Lay the back adhesive film 6. The width of the back adhesive film 6 is consistent with that of the shielding adhesive film 4. The back adhesive film 6 mainly serves to protect the battery cell 1.

[0070] Among them, the back film 6 needs to be cut open at the lead wire position to form the back film opening 16. The size, position and data of the opening are determined according to the number and type of the battery cells.

[0071] Among them, the width of the back film 6 is consistent with the width of the front glass 3 and the back glass 7 of the module, and the thickness of the back film 6 is consistent with that of conventional films, with a thickness of 0.4 to 0.6 mm, which mainly serves to protect the battery cell 1.

[0072] The back adhesive film 6 can be white, black, black inside and white outside, or other colors that meet appearance requirements;

[0073] Step 8: Process the back glass opening 17 on the back glass 7, and lay the back glass 7 with the opening in the center. The back glass 7 can be made of tempered glass or float glass, and the thickness is set to 1.6~2.0mm.

[0074] Step 9: Use a tooling fixture to fix the stacked back material on the vacuum adsorption platform to ensure that the battery cell 1 and the back material will not move during the flipping process; activate the 180° flipping function of the vacuum adsorption platform to flip the stacked back material to another plane, and the vacuum adsorption platform will break the vacuum, so that the glass surface of the back glass 7 is on the plane of the other platform.

[0075] Step 10: Lay the front adhesive film 2 and the front glass 3 in the center to complete the module stacking process;

[0076] Among them, the front encapsulant film 2 is a high-transparency transparent encapsulant film, which can be EVA / EPE / POE or other photovoltaic module encapsulant films. The thickness is the same as or thinner than the encapsulant film used for conventional module encapsulation (there are no grid lines on the front, so it can be thinner).

[0077] Among them, the front glass 3 uses conventional tempered ultra-clear patterned glass with a thickness of 1.6 to 2.0 mm;

[0078] Step 11: Finally, the fabrication of a back-contact battery double-glass module is completed through processes such as lamination and assembly.

[0079] The working principle and beneficial effects of the above technical solution are as follows:

[0080] The double-glass back-contact battery module provided in this embodiment adopts processes such as overall layout, isolation and shielding, and welding. Compared with other back-contact module packaging processes, it is simpler and requires lower precision from equipment, which can improve the process yield and further reduce the manufacturing cost of the back-contact module.

[0081] The back-contact battery double-glass module provided in this embodiment adopts an integrated film laying process compared with the current back-contact white, all-black or other colored modules. Compared with the existing string-to-string shielding method, the laying process is simpler and the cost is lower. At the same time, the shielding film 4 is laid as a whole, the color is more uniform, there is no shielding color difference, and the appearance is more beautiful, which is particularly suitable for scenarios with high appearance requirements.

[0082] like Figure 12 , Figure 13 As shown, in one embodiment, the battery cell 1 can be configured as a half-cell multi-grid back-contact battery, with the number of grid lines set to 10 to 20 lines; the position of the opening 8 on the shielding film 4 corresponds to the position of the grid line solder joint, the solder ribbon 12 connects the grid lines between adjacent battery cells 1, and the busbar connects the head, middle and tail of the solder ribbon 12.

[0083] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0084] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the protection scope of this invention.

Claims

1. A back-contact battery double-glass module, characterized in that, include: The battery cell layer has a front adhesive film (2) and a front glass (3) arranged sequentially on the front side; a shielding adhesive film (4), a conductive layer (5), a back adhesive film (6) and a back glass (7) arranged sequentially on the back side; the battery cell layer includes multiple battery cells (1) arranged according to the design circuit; the shielding adhesive film (4) has multiple openings (8), the positions of the openings (8) correspond to the positions of the electrodes on the battery cells (1); the conductive layer (5) passes through the openings (8) and connects to the electrodes.

2. The back-contact battery double-glass module according to claim 1, characterized in that, The electrode on the battery cell (1) is centered relative to the opening (8), and the width of the opening (8) is greater than the width of the electrode, with the difference set to 3-5 mm.

3. A back-contact battery double-glass module according to claim 2, characterized in that, The width of the shielding film (4) is equal to the width of the front glass (3) and the back glass (7), and the thickness of the shielding film (4) is set to 0.2 to 0.25 mm.

4. A back-contact battery double-glass module according to claim 1, characterized in that, The shielding film (4) is set to any one of EVA film, EPE film, or POE film.

5. A back-contact battery double-glass module according to claim 1, characterized in that, A positive electrode (9) and a negative electrode (10) are provided on the back of the battery cell (1). The positive electrode (9) and the negative electrode (10) are located on the horizontal sides of the battery cell (1), respectively. The positive electrodes (9) and the negative electrodes (10) of adjacent battery cells (1) are arranged alternately in the horizontal and vertical directions. The battery cells (1) in the horizontal direction can be symmetrically arranged into two groups.

6. A back-contact battery double-glass module according to claim 1, characterized in that, It also includes a positioning tape (11), with both ends of the positioning tape (11) connected to the adjacent solar cells (1) in the longitudinal direction, and the connection point is the midpoint of the edge of the solar cell (1). The positioning tape (11) is set as a high-temperature tape for photovoltaic applications.

7. A back-contact battery double-glass module according to claim 6, characterized in that, Positioning tape (11) is set at intervals along the transverse direction of each column of battery cell (1).

8. A back-contact battery double-glass module according to claim 5, characterized in that, The conductive layer (5) includes a solder strip (12), which is connected between the electrodes of the horizontal battery cell (1). The two ends of the solder strip (12) correspond to the positive electrode (9) of the previous battery cell (1) and the negative electrode (10) of the next battery cell (1), respectively. The horizontal battery cells (1) are welded to form a battery string.

9. A back-contact battery double-glass module according to claim 8, characterized in that, The conductive layer (5) also includes a middle busbar (13), a head busbar (14) and a tail busbar (15). The middle busbar (13) is connected to the solder strip (12) between the electrodes of the two sets of battery cells (1) in the lateral direction; the head busbar (14) is welded to the electrode at the head of the battery cell (1) in the lateral direction; and the tail busbar (15) is welded to the electrode at the tail of the battery cell (1) in the lateral direction.

10. A back-contact battery double-glass module according to claim 9, characterized in that, The middle busbar (13) is connected to the lead wire, and the back film (6) is provided with a back film opening (16) corresponding to the lead wire; the back glass (7) is provided with a back glass opening (17) corresponding to the lead wire.

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