Conductive interconnection piece of shingled assembly, shingled assembly and preparation method

Abstract

The present invention provides a conductive interconnection part of a shingled assembly, a shingled assembly and a preparation method, and relates to the field of photovoltaic technology. The conductive interconnection part includes: a conductive layer, and an insulating layer and an electrical connector located on one side of the conductive layer; the conductive layer has a conductive circuit; the insulating layer has an opening, and each electrical connector is located in the opening of the insulating layer; the electrical connector is divided into a first electrical connector and a second electrical connector; the first electrical connector is used to conductively connect the first electrode of the back-contact solar cell, and the conductive circuit; the second electrical connector is used to conductively connect the second electrode of the back-contact solar cell, and the conductive circuit; the polarity of the first electrode and the second electrode are opposite. Two overlapping back-contact solar cells are connected in series to the conductive layer through the first electrical connector and the second electrical connector to form a battery string. The process is simple, and the first electrode and the second electrode are electrically isolated by the insulating layer without openings, which can avoid short circuits.

Description

Technical Field

[0001] The present invention relates to the field of photovoltaic technology, and in particular to a conductive interconnection piece of a shingled assembly, a shingled assembly and a preparation method thereof. Background Art

[0002] Back-contact solar cells have no electrodes on the light-facing side, which reduces shading, increases the short-circuit current of the battery, and is more beautiful, so they are widely used.

[0003] Overlapping portions of each back-contact solar cell to form a shingled module can increase the power output of the module and make it more beautiful in appearance.

[0004] However, in the process of forming a shingled assembly for a back-contact solar cell, the process is complicated because the electrodes are all arranged on the backlight surface. Summary of the invention

[0005] The present invention provides a conductive interconnection piece of a shingled assembly, a shingled assembly and a preparation method, aiming to solve the problem of complex process in forming a shingled assembly for a back-contact solar cell.

[0006] According to a first aspect of the present invention, a conductive interconnection of a shingled assembly is provided, the conductive interconnection comprising: a conductive layer, and an insulating layer and an electrical connector located on one side of the conductive layer; the conductive layer has a conductive line;

[0007] The insulating layer has an opening, and each of the electrical connectors is located in the opening of the insulating layer;

[0008] The electrical connector is divided into a first electrical connector and a second electrical connector;

[0009] The first electrical connector is used to conductively connect the first electrode of the back contact solar cell and the conductive line;

[0010] The second electrical connector is used to conductively connect the second electrode of the back contact solar cell and the conductive line;

[0011] The first electrode and the second electrode have opposite polarities;

[0012] Between the overlapping regions of adjacent back contact solar cells, as the height of the electrical connector increases, the width of the electrical connector gradually increases, wherein the height is the dimension of the electrical connector in a direction perpendicular to the conductive layer;

[0013] The conductive lines are patterned so that the conductive interconnect can connect several back-contact solar cells in series.

[0014] In the embodiment of the present invention, the first electrode of the back contact solar cell and the conductive line of the conductive layer are conductively connected by the first electrical connector located on one side of the conductive layer, and the second electrode of the back contact solar cell and the conductive line of the conductive layer are conductively connected by the second electrical connector located on one side of the conductive layer. The polarities of the first electrode and the second electrode are opposite, that is, the overlapping back contact solar cells are connected in series to the conductive layer through the first electrical connector and the second electrical connector to form a battery string, and the process is simple. At the same time, the above-mentioned conductive connector located on one side of the conductive layer can play a certain supporting role for external forces, can improve the connection strength, reduce the risk of battery or component rupture, and improve the reliability of the component. At the same time, the overlapping arrangement of the back contact solar cells makes full use of the limited area in the component, improves the output power, reduces the loss in the component, and improves the conversion efficiency of the component. Moreover, the first electrical connector connecting the first electrode of the back contact solar cell and the second electrical connector connecting the back contact solar cell are located in the opening of the insulating layer, and the first electrode and the second electrode are further electrically isolated by the insulating layer without openings, which can avoid the short circuit between the first electrode and the second electrode. The above-mentioned insulating layer can also play a certain supporting role for external forces, can improve the connection strength, reduce the risk of battery or component rupture, and improve the reliability of the component.

[0015] According to a second aspect of the present invention, there is provided a shingled assembly comprising at least two overlappingly arranged back-contact solar cells;

[0016] Using the first electrical connector in the conductive interconnection member of the shingled assembly as described above to conductively connect the first electrode of the back-contact solar cell and the conductive line in the conductive interconnection member as described above;

[0017] Adopting the second electrical connector in any of the above-mentioned conductive interconnects to conductively connect the second electrode of the back-contact solar cell and the conductive line;

[0018] The first electrode and the second electrode have opposite polarities.

[0019] According to a third aspect of the present invention, there is provided a method for preparing a shingled assembly, comprising the following steps:

[0020] Providing a conductive interconnection member of the shingled assembly as described above;

[0021] Laying at least a back-contact solar cell on the conductive interconnect to obtain a component precursor, so that a first electrical connector in the conductive interconnect is opposite to a first electrode of the back-contact solar cell, and a second electrical connector is opposite to a second electrode of the back-contact solar cell; the first electrode and the second electrode have opposite polarities;

[0022] A stack including the assembly precursor is laminated such that the first electrode is conductively connected to the conductive trace of the conductive interconnect through the first electrical connector, and the second electrode is conductively connected to the conductive trace of the conductive interconnect through the second electrical connector.

[0023] The above-mentioned conductive interconnect production method, shingled assembly, and shingled assembly preparation method have the same or similar beneficial effects as the aforementioned conductive interconnect, and will not be described again here to avoid repetition. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0025] Figure 1 A schematic structural diagram of a conductive interconnection member in an embodiment of the present invention is shown;

[0026] Figure 2 A schematic structural diagram of an insulating layer in an embodiment of the present invention is shown;

[0027] Figure 3 A schematic structural diagram of a shingled assembly in an embodiment of the present invention is shown;

[0028] Figure 4 A schematic diagram of the structure of a first overlapping back-contact solar cell in an embodiment of the present invention is shown;

[0029] Figure 5 A schematic diagram showing the structure of a second overlapping back-contact solar cell in an embodiment of the present invention is shown;

[0030] Figure 6 A schematic structural diagram of a first back-contact solar cell in an embodiment of the present invention is shown;

[0031] Figure 7 A schematic diagram showing the structure of a third overlapping back-contact solar cell in an embodiment of the present invention is shown;

[0032] Figure 8 A schematic structural diagram of a second conductive interconnection member in an embodiment of the present invention is shown;

[0033] Fig. 9 A schematic structural diagram of a fourth overlapping back-contact solar cell in an embodiment of the present invention is shown.

[0034] Description of the accompanying drawings:

[0035] 1-conductive layer, 2-electrical connector, 21-first electrical connector, 22-second electrical connector, 3-back contact solar cell, 31-first electrode, 32-second electrode, 33-first diffusion region, 34-second diffusion region, 35-semiconductor substrate, 36-short side, 37-chamfer, 311-first connecting electrode, 312-first fine grid line, 321-second connecting electrode, 322-second fine grid line, 4-insulating layer, 41-opening, 11-metal foil, 12-isolation region, 13-binding site, 5-cover plate, 6-back plate, 7-sealing layer, 8-anti-pressure pad. DETAILED DESCRIPTION

[0036] 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 part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] In the embodiment of the present invention, referring to Figure 1 As shown, Figure 1 FIG. 1 is a schematic diagram showing the structure of a conductive interconnection member in an embodiment of the present invention. The conductive interconnection member comprises: a conductive layer 1, an insulating layer 4 and an electrical connector 2 located on one side of the conductive layer 1. The conductive layer 1 has a conductive line ( Figure 1 not shown).

[0038] The insulating layer 4 and the electrical connection body 2 are located on the same side of the conductive layer 1 . Figure 2 FIG. 2 shows a schematic diagram of the structure of an insulating layer in an embodiment of the present invention. Figure 2 As shown, the insulating layer 4 has openings 41. Figure 3 As shown, Figure 3 The schematic diagram of the structure of a shingled assembly in an embodiment of the present invention is shown. Each of the electrical connectors 2 is located in the opening of the insulating layer 4. That is, each of the electrical connectors 2 protrudes out of the conductive layer 1 and extends out of the opening of the insulating layer 4.

[0039] In the shingled assembly, two adjacent back-contact solar cells 3 are arranged in an overlapping manner. The size of the overlapping region is not specifically limited.

[0040] Reference Figure 3As shown, the electrical connector is divided into: a first electrical connector 21 and a second electrical connector 22. The first electrical connector 21 is used to conductively connect the first electrode 31 of the back contact solar cell 3 region and the conductive circuit in the conductive layer 1. For example, the first electrical connector 21 conductively connects the first electrode 31 of the non-overlapping region of one of the two overlapping back contact solar cells 3 and the conductive circuit in the conductive layer 1. Figure 3 In the figure, the back contact solar cell 3 on the left is conductively connected to the conductive layer 1 through the first electrical connector 21 and the first electrode 31. The second electrical connector 21 is used to conductively connect the second electrode 32 of the back contact solar cell 3 and the conductive circuit in the conductive layer 1. For example, the second electrical connector 21 conductively connects the second electrode 32 of the non-overlapping area of ​​the other back contact solar cell 3 of the two overlapping back contact solar cells 3 and the conductive circuit in the conductive layer 1. Figure 3 In the figure, the back-contact solar cell 3 on the right is conductively connected to the conductive layer 1 through the second electrical connector 22 and the second electrode 32. The polarities of the first electrode 31 and the second electrode 32 are opposite. For example, if the first electrode 31 is a positive electrode, the second electrode 32 can be a negative electrode. Furthermore, the two back-contact solar cells 3 on the left and right are connected in series to the conductive layer 1 through the first electrical connector 21 and the second electrical connector 22, forming an overlapping battery string with a simple process. At the same time, the conductive connector 2 protruding from the conductive layer 1 can play a certain supporting role against external forces, which can improve the connection strength, reduce the risk of battery or component rupture, and improve the reliability of the component.

[0041] It should be noted that the first electrical connector is used to conductively connect the first electrode of a back-contact cell, and the second electrical connector is used to conductively connect the second electrode of the same back-contact cell, and the polarities of the first electrode and the second electrode are opposite. The first electrical connector is also used to conductively connect the first electrode of one back-contact cell of two overlapping back-contact solar cells, and the second electrical connector is also used to conductively connect the second electrode of the other back-contact cell of the two overlapping back-contact solar cells.

[0042] The pattern of the conductive lines is arranged so that the conductive interconnects can connect a plurality of back-contact solar cells in series, thereby facilitating the formation of a shingled assembly of back-contact solar cells.

[0043] Figure 4 A schematic structural diagram of a first overlapping back-contact solar cell in an embodiment of the present invention is shown. Figure 5 A schematic structural diagram of a second overlapping back-contact solar cell in an embodiment of the present invention is shown. Figure 4 , Figure 5 Can be a front view. Figure 3 , Figure 4 , Figure 5 As shown, the back contact solar cells 3 are arranged in an overlapping manner, which fully utilizes the limited area within the component, increases the output power, reduces the loss within the component, and improves the conversion efficiency of the component.

[0044] It should be noted that there is an insulating gap between the first electrical connector 21 and the second electrical connector 22. The shape of the surface of the first electrical connector 21 facing the first electrode 31 matches the shape of the backlight surface of the first electrode 31 in the overlapping back-contact solar cell 3, and thus the contact area is large to ensure good electrical conductivity. The shape of the surface of the second electrical connector 22 facing the second electrode 32 matches the shape of the backlight surface of the second electrode 32 in the overlapping back-contact solar cell 3, and thus the contact area is large to ensure good electrical conductivity.

[0045] The electrodes of the back-contact solar cell are all arranged on the backlight side, and the light-facing side is used to collect sunlight radiation. The backlight side of the back-contact solar cell can also collect diffuse light, so that double-sided sunlight collection can be achieved. In the overlapping process, the backlight side of one back-contact solar cell is overlapped and arranged on the light-facing side of another back-contact solar cell. For example, referring to Figure 3 As shown, the light-repelling surface of the back-contact solar cell 3 on the left is arranged to overlap the light-facing surface of the back-contact solar cell 3 on the right.

[0046] Figure 6 FIG. 1 shows a schematic diagram of the structure of a first back-contact solar cell in an embodiment of the present invention. Figure 6 As shown, the back contact solar cell comprises a first electrode 31 in contact with a first diffusion region 33 and a second electrode 32 in contact with a second diffusion region 34. The first electrode 31 and the second electrode 32 are formed on the backlight surface of a semiconductor substrate 35 and there is an electrical insulation gap between them. The polarity of the second electrode 32 is opposite to that of the first electrode 31.

[0047] Figure 7 A schematic structural diagram of a third overlapping back-contact solar cell in an embodiment of the present invention is shown. Figure 7 It can be a bottom view from the backlit side to the lighted side. Figure 7 As shown, the first electrode 31 is composed of a first connecting electrode 311 and a first fine gate line 312. Figure 6The first connecting electrode 311 is connected to the first thin gate line 312. The second electrode 32 is composed of a second connecting electrode 321 and a second thin gate line 322. The second thin gate line 322 is in contact with the second diffusion region 34 on the backlight surface of the semiconductor substrate 35, and the second connecting electrode 321 is connected to the second thin gate line 322. The first electrical connector can be conductively connected to the first connecting electrode 311, and the second electrical connector can be conductively connected to the second connecting electrode 321.

[0048] The above-mentioned back contact solar cell can be a whole cell, or can be a sliced ​​cell after the whole cell is sliced. In the embodiment of the present invention, there is no specific limitation on this. A whole cell can be sliced ​​into 2-10 sliced ​​cells. Each sliced ​​cell can have approximately equal area, approximately equal width, length, etc. In the embodiment of the present invention, there is no specific limitation on this.

[0049] Each of the above-mentioned electrical connectors 2 protrudes out of the conductive layer 1 and extends out from the opening of the insulating layer 4. Then, the first electrical connector 21 is conductively connected to the first electrode 31 of the back-contact solar cell 3 and the conductive circuit in the conductive layer 1. The second electrical connector 22 is conductively connected to the second electrode 32 of the back-contact solar cell 3 and the conductive circuit in the conductive layer 1. Then, the positions of the openings 41 of the insulating layer 4 need to correspond to the positions of the first electrode and the second electrode on the back-contact solar cell, respectively. For the same back-contact solar cell, the first electrical connector connecting the first electrode of the back-contact solar cell and the second electrical connector connecting the same back-contact solar cell both extend out of the opening of the insulating layer 4. The polarities of the first electrode and the second electrode are opposite. The two are further electrically isolated by the insulating layer 4 without openings, which can avoid the short circuit between the first electrode and the second electrode of the same back-contact solar cell. At the same time, the above-mentioned insulating layer 4 can also play a certain supporting role against external forces, which can improve the connection strength, reduce the risk of battery or component rupture, and improve the reliability of the component.

[0050] The insulating layer 4 needs to have a relatively large insulation resistance and a certain resistance to thermal deformation, so that the insulating layer 4 is less deformed during the lamination process, which helps to ensure the alignment of the electrodes of the back-contact solar cell and the electrical connector.

[0051] Optionally, the insulating layer is a polymer multilayer structure composed of an insulating material layer and a thermal bonding layer, and the material of the insulating material layer is selected from at least one of polyimide (PI), polyethylene naphthalate (PEN), polyethylene terephthalate (PET), and polypropylene (PP). The material of the thermal bonding layer is selected from at least one of polyethylene-vinyl acetate (EVA), polyvinyl butyral (PVB), and polyolefin (POE). The insulating layer of the above structure and material has good insulation effect, small deformation during lamination, and is easy to open holes.

[0052] Optional, see Figure 1 As shown, in the stacking direction of the conductive layer 1 and the insulating layer 4, or in the direction perpendicular to the conductive layer 1, the thickness h1 of the insulating layer 4 is less than or equal to 500um. Preferably, the thickness h1 of the insulating layer 4 can be 50-200um, and the insulating layer 4 of the above thickness has the advantages of low cost, good electrical insulation performance, and small thermal deformation.

[0053] Between the overlapping areas of adjacent back-contact solar cells, as the height of the electrical connector increases, the width of the upper electrical connector gradually increases. The height is the dimension of the electrical connector in the direction perpendicular to the conductive layer, so that even if the height of a certain electrical connector is large, since its width is also large, the resistance of the electrical connector will not be very large, reducing power loss. Moreover, the resistance of each electrical connector is not much different or equal, which is convenient for current collection and is conducive to reliable connection between the battery electrode and the conductive layer.

[0054] For example, refer to Figure 1 As shown, in the direction perpendicular to the conductive layer 1, the heights of the three electrical connectors 2 on the right are in a relationship of h4>h3>h2. Then, in the direction parallel to the conductive layer 1, the widths of the three electrical connectors 2 on the right are in a relationship of w4>w3>w2. For the electrical connector 2 with a height of h4, although its height is large, its width is also large, so the resistance will not be very large, reducing power loss. Moreover, the resistances of the three electrical connectors 2 with heights of h4, h3, and h2 are not much different or are equal, which is convenient for current collection and conducive to reliable connection between the battery electrode and the conductive layer 1.

[0055] Optionally, the material of the electrical connector is selected from at least one of conductive paste, solder, solder paste, conductive ink, isotropic conductive adhesive, anisotropic conductive adhesive, metal, and metal alloy conductor, and the electrical connector of the above materials has good conductivity. The shape of the above electrical connector can be set according to actual needs, for example, the shape of the electrical connector can be cylindrical or block-shaped, etc. In the embodiment of the present invention, there is no specific limitation on this.

[0056] Optionally, the conductive layer is a patterned metal foil or a plurality of conductive lines disposed on the adhesive film. Figure 8 As shown, Figure 8 A schematic structural diagram of a conductive layer in an embodiment of the present invention is shown. Figure 8 The conductive layer shown is a patterned metal foil. Figure 8 11 is a metal foil, and 12 is a patterned isolation area. The width of the isolation area 12 is not specifically limited. Patterning methods include mechanical punching, laser punching or chemical etching. The pattern depends on the pattern of the electrode on the back contact surface of the solar cell, and the pattern may include various shapes and / or sizes. The metal foil can be copper foil or aluminum foil or any other suitable metal or metal alloy. For example, the main component of the metal foil can be at least one of: copper, silver, aluminum, nickel, magnesium, iron, titanium, molybdenum, and tungsten.

[0057] The thickness of the metal foil can be 10um-50um, and the metal foil of the above thickness can provide a current path with low resistance. The metal foil 11 can also be provided with binding sites 13 corresponding to each conductive area in the conductive layer to facilitate accurate alignment of the conductive layers.

[0058] The embodiment of the present invention further provides a shingled assembly, such as Figure 3 The shingled assembly shown includes at least two overlapping back-contact solar cells 3, a first electrical connector 21 in any of the aforementioned conductive interconnects is used to conductively connect the first electrode 31 of the back-contact solar cell 3, and a conductive line in any of the aforementioned conductive interconnects, and a second electrical connector 22 in any of the aforementioned conductive interconnects is used to conductively connect the second electrode 32 of the back-contact solar cell 3, and a conductive line. The polarities of the first electrode and the second electrode are opposite.

[0059] The back contact solar cell and the conductive interconnection member in the shingled assembly can refer to the above-mentioned related records, and will not be described here in detail to avoid repetition. The shingled assembly can achieve the same or similar beneficial effects as the above-mentioned conductive interconnection member.

[0060] Reference Figure 7 As shown, the back contact solar cell 3 includes a short side 36 parallel to the series connection direction of each back contact solar cell or parallel to the cell string formed by each back contact solar cell. In the direction parallel to the short side 36, the size L1 of the overlapping area of ​​two overlapping back contact solar cells is 5%-50% of the length L2 of the short side 36. Since the electrodes in the overlapping area usually cannot be connected in series to the conductive layer, or the current loss is large during the process of being connected in series to the conductive layer, the size of the above-mentioned overlapping area makes the area of ​​the remaining non-overlapping area larger, so that more electrodes are connected in series to the conductive layer 1, thereby reducing the problem of current being unable to be collected due to overlap.

[0061] For example, refer to Figure 7As shown, the first electrode 31 is composed of a first connection electrode 311 and a first fine grid line 312, and the first connection electrode 311 is connected to the first fine grid line 312. The first electrical connector is conductively connected to the first connection electrode 311 of the back contact solar cell. The first connection electrode 311 is parallel to the series connection direction of each back contact solar cell or parallel to the battery string formed by each back contact solar cell, and the short side direction is parallel to the first connection electrode 311.

[0062] Optionally, in a direction parallel to the short side of the back contact solar cell, the size of the overlapping area of ​​the two overlapping back contact solar cells is 0.3 mm to 3 mm. Figure 3 As shown, in the direction parallel to the short side of the back contact solar cell 3, the size A of the overlapping area of ​​the two overlapping back contact solar cells 3 is 0.3mm-3mm. The overlapping area of ​​the above size not only makes the overlapping arrangement of the two back contact cells reliable, but also, the electrodes in the overlapping area usually cannot be connected in series to the conductive layer 1, or the current loss is large during the process of being connected in series to the conductive layer 1. The size of the above overlapping area makes the area of ​​the remaining non-overlapping area larger, and thus more electrodes are connected in series to the conductive layer 1, reducing the problem of current being unable to be collected due to overlap.

[0063] It should be noted that the area of ​​the overlapping region of the two overlapping back contact solar cells can be determined by the length L3 of the long side of the back contact solar cell and the size L1 of the overlapping region of the two overlapping back contact solar cells in a direction parallel to the short side 36. In the case of arranging electrodes in the overlapping region, the smaller the area of ​​the overlapping region, the smaller the problem of the current not being able to be collected due to the overlap.

[0064] Optionally, the overlapping region of the two overlapping back-contact solar cells includes a non-electrode region where no electrode is set. Since the electrode in the overlapping region usually cannot be connected in series to the conductive layer, or the current loss is large in the process of being connected in series to the conductive layer, the overlapping region includes the non-electrode region where no electrode is set, which can reduce the output loss from the electrode resistance. In addition, when the back-contact solar cells are connected using a stacking method, the reduction in the photoelectric conversion efficiency of the back-contact solar cells caused by the dark current generated in the overlapping region is reduced, and the output power of the shingled assembly can be improved.

[0065] It should be noted that, in the overlapping region, the first electrode or the second electrode in the electrode region where the electrode is provided is formed adjacent to the non-electrode region.

[0066] Optionally, the area of ​​the non-electrode region of the overlapping region of the two overlapping back-contact solar cells is 50%-90% of the area of ​​the overlapping region, and thus no electrode is provided in most of the overlapping region, which can further reduce the output loss from the electrode resistance. In addition, when the back-contact solar cells are connected by stacking, the reduction in the photoelectric conversion efficiency of the back-contact solar cells caused by the dark current generated in the overlapping region is further reduced, and the output power of the shingled assembly can be improved.

[0067] Optional, see Figure 3 As shown, the shingled component also includes: an anti-pressure pad 8 located in the overlapping area of ​​two overlapping back-contact solar cells, the Young's modulus of the anti-pressure pad 8 is greater than 5Mpa, and the above-mentioned anti-pressure pad 8 can absorb stress, reduce hidden cracks, and improve the reliability of the component.

[0068] The shape of the pressure-proof pad 8 is not specifically limited, for example, the shape of the pressure-proof pad 8 can be circular, etc. The pressure-proof pad 8 can be a continuous whole strip or a discontinuous strip, which is not specifically limited in the embodiment of the present invention.

[0069] Optionally, the material of the pressure-proof pad is selected from at least one of epoxy resin, acrylate, silicone, imide, bismaleimide, siloxane, vinyl acetate, polyolefin, polyimide, acrylate, polyurethane, cyanoacrylate, and phenolic resin. The pressure-proof pad of the above material not only has a good stress absorption effect, but also has a low cost. At the same time, the pressure-proof pad of the above material has a certain bonding performance, which can play the role of bonding two overlapping back-contact solar cells, thereby improving the reliability of the overlap.

[0070] Optionally, the pressure-proof pad is a tape, which includes a backing layer, one side of the backing layer is coated with an adhesive, and the material of the backing layer is selected from: paper, polymer film, cloth, metal foil, and the pressure-proof pad of the material not only has a good stress absorption effect, but also has a low cost. At the same time, the pressure-proof pad of the material has a certain adhesive property, which can play a role in bonding two overlapping back-contact solar cells, thereby improving the reliability of the overlap.

[0071] It should be noted that there is no specific limitation on whether the pressure-proof pad is conductive. For example, the pressure-proof pad may not be conductive, thereby reducing the cost.

[0072] Optionally, the first electrode is composed of a pad and a gate line connecting adjacent pads, and the first electrical connector is conductively connected to the pad of the first electrode, so that the conductive connection is reliable. For example, the first connection electrode of the first electrode is composed of a pad and a gate line connecting adjacent pads, and the first electrical connector is conductively connected to the pad of the first connection electrode.

[0073] And / or, the second electrode is composed of a pad and a gate line connecting adjacent pads, and the second electrical connector is conductively connected to the pad of the second electrode, so that the conductive connection is reliable. For the conductive interconnect with an insulating layer, the opening position of the insulating layer corresponds to the pad one by one. For example, the second connection electrode of the second electrode is composed of a pad and a gate line connecting adjacent pads, and the second electrical connector is conductively connected to the pad of the second connection electrode.

[0074] Optional, see Figure 7 As shown, one end of the back contact solar cell 3 is provided with a chamfer 37, and the other end is not provided with a chamfer. Fig. 9 As shown, Fig. 9 A schematic structural diagram of a fourth overlapping back-contact solar cell in an embodiment of the present invention is shown. Fig. 9 Can be Figure 7 The overlapping back contact cells shown are viewed from the light-facing side to the back-light side. In the shingled module, the end of one back contact solar cell 3 without chamfer is overlapped on the end of another back contact solar cell 3 with chamfer 37, and then the end with chamfer is pressed under the end without chamfer. When viewed from the light-facing side, the chamfer cannot be seen, which can improve the aesthetics of the shingled module. Fig. 9 Reference numeral 11 is an opening in the insulating layer.

[0075] Optional, see Figure 3 As shown, the shingled assembly further includes: a cover plate 5 located on the light-facing side of the back-contact solar cell 3, and a back plate 6 located on the back-light side of the back-contact solar cell 3. A sealing layer 7 is also provided between the cover plate 5 and the back plate 6, around the back-contact solar cell 3. The sealing material of the sealing layer 7 is selected from at least one of ethylene / vinyl acetate copolymer (EVA), ethylene / α-olefin copolymer, polyvinyl butyl ester (PVB), acrylic resin, polyurethane resin, and silicone resin. The sealing layer of the above materials can play a good role in absorbing stress, can reduce hidden cracks, and improve the reliability of the assembly.

[0076] The shape of the sealing layer 7 is specifically adapted to the shape between the cover plate 5 and the back plate 6 and around the back contact solar cell 3, and may be in the form of a sheet, etc. In the embodiment of the present invention, no specific limitation is made to this.

[0077] It should be noted that the cover plate 5 located on the light-facing side of the back-contact solar cell 3 and the sealing layer 7 located on the light-facing side of the back-contact solar cell 3 are light-transmissive. The material of the sealing layer 7 can be liquid or solid, and the sealing material can be added separately and can flow to the overlapping area during lamination. The shingled assembly is encapsulated by curing or laminating the sealant, and the back-contact solar cell is joined between the back plate and the transparent cover plate to form a laminate. The final laminate can be installed together with a frame to produce a shingled assembly. The encapsulant used for the shingled assembly can provide electrical insulation, reduce moisture intrusion, and protect the shingled assembly from mechanical stress and / or corrosion.

[0078] The material of the cover plate is selected from a material that is light-transmitting but resistant to ultraviolet rays, such as glass or a transparent resin such as acrylic resin or polycarbonate resin. The back plate can be a material that prevents water from entering (high water resistance). For example, a resin film such as polyethylene terephthalate (PET), polyethylene (PE), olefin resin, fluorine-containing resin or silicone-containing resin, or a laminate of a light-transmitting plate-shaped resin member such as glass, polycarbonate, acrylic, or a metal foil such as aluminum foil.

[0079] Optionally, the shingled assembly may further include a front anti-reflection layer located on the light-facing surface of the cover plate to reduce light reflection. The light-facing surface and / or the backlight surface of the cover plate may have a light trapping structure to increase the optical path. For example, the light-facing surface and / or the backlight surface of the cover plate may be processed into a concave-convex shape to guide more light into the photovoltaic assembly.

[0080] The embodiment of the present invention also provides a method for preparing a shingled assembly, the production method comprising the following steps:

[0081] Step SA1, providing any conductive interconnection member as described above.

[0082] Step SA2, laying at least two overlapping back-contact solar cells on the conductive interconnect to obtain a component precursor, so that the first electrical connector in the conductive interconnect is opposite to the first electrode of the back-contact solar cell, and the second electrical connector is opposite to the second electrode of the back-contact solar cell; the polarities of the first electrode and the second electrode are opposite.

[0083] Step SA3, laminating the stack including the component precursor so that the first electrode is conductively connected to the conductive line of the conductive interconnection through the first electrical connector, and the second electrode is conductively connected to the conductive line of the conductive interconnection through the second electrical connector.

[0084] The laminated member including the aforementioned component precursor may be: the light-facing surface of the component precursor may be paved with a sealing layer and a cover plate, and the backlight surface of the component precursor may be paved with a sealing layer and a back plate. The various parts of the shingled assembly refer to the aforementioned related records and can achieve similar beneficial effects. In order to avoid repetition, they will not be described here.

[0085] The embodiments of the present invention are described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific embodiments. The above-mentioned specific embodiments are merely illustrative and not restrictive. Under the enlightenment of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the purpose of the present invention and the claims, which all fall within the protection of the present invention.

Claims

1. A conductive interconnection member of a shingled assembly, characterized in that: The conductive interconnection element comprises: a conductive layer, and an insulating layer and an electrical connector located on one side of the conductive layer; the conductive layer has a conductive line; The insulating layer has an opening, and each of the electrical connectors is located in the opening of the insulating layer; The electrical connector is divided into a first electrical connector and a second electrical connector; the first electrical connector is used to conductively connect the first electrode of the back-contact solar cell and the conductive line; the second electrical connector is used to conductively connect the second electrode of the back-contact solar cell and the conductive line; the polarities of the first electrode and the second electrode are opposite; Between the overlapping regions of adjacent back contact solar cells, as the height of the electrical connector increases, the width of the electrical connector gradually increases, wherein the height is the dimension of the electrical connector in a direction perpendicular to the conductive layer; The conductive lines are patterned so that the conductive interconnect can connect several back-contact solar cells in series.

2. The conductive interconnect of the shingled assembly according to claim 1, characterized in that: The material of the electrical connector is selected from at least one of: conductive paste, solder, solder paste, conductive ink, isotropic conductive adhesive, anisotropic conductive adhesive, metal, and metal alloy conductor.

3. The conductive interconnect of the shingled assembly according to claim 1, characterized in that: The insulating layer is a polymer multilayer structure composed of an insulating material layer and a thermal bonding layer; The material of the insulating material layer is selected from at least one of polyimide, polyethylene naphthalate, polyethylene terephthalate, and polypropylene; The material of the thermal bonding layer is selected from at least one of polyethylene-vinyl acetate, polyvinyl butyral, and polyolefin.

4. The conductive interconnection member of the shingled assembly according to any one of claims 1 to 3, characterized in that: The thickness of the insulating layer is less than or equal to 500 um.

5. The conductive interconnection member of the shingled assembly according to any one of claims 1 to 3, characterized in that: The conductive layer is a patterned metal foil or a plurality of conductive lines arranged on an adhesive film; The thickness of the metal foil is 10 μm-50 μm.

6. A shingled assembly, characterized in that: comprising at least two back-contact solar cells arranged in an overlapping manner; A first electrical connector in a conductive interconnection member of a shingled assembly as claimed in any one of claims 1 to 5 is used to conductively connect a first electrode of a back-contact solar cell, and a conductive line in a conductive interconnection member of a shingled assembly as claimed in any one of claims 1 to 5; The second electrical connector in the conductive interconnect of the shingled assembly according to any one of claims 1 to 5 is used to conductively connect the second electrode of the back-contact solar cell and the conductive line; The first electrode and the second electrode have opposite polarities.

7. The shingled assembly according to claim 6, characterized in that: The size of the overlapping area of ​​two overlapping back-contact solar cells is 5%-50% of the short side size.

8. The shingled assembly according to claim 7, characterized in that: In a direction parallel to the short side, a size of an overlapping area of ​​two overlapping back-contact solar cells is 0.3 mm to 3 mm.

9. The shingled assembly according to claim 6 or 7, characterized in that: The overlapping region of the two overlapping back-contact solar cells includes a non-electrode region where no electrode is disposed.

10. The shingled assembly according to claim 9, characterized in that: The area of ​​the non-electrode region is 50%-90% of the area of ​​the overlapping region.

11. The shingled assembly according to claim 6 or 7, characterized in that: Also includes: An anti-pressure pad located at an overlapping area of ​​two overlapping back-contact solar cells; The Young's modulus of the anti-pressure pad is greater than 5 MPa.

12. The shingled assembly according to claim 11, characterized in that: The material of the pressure-proof pad is selected from at least one of epoxy resin, acrylate, silicone, imide, bismaleimide, siloxane, vinyl acetate, polyolefin, polyimide, acrylate, polyurethane, cyanoacrylate, and phenolic resin.

13. The shingled assembly according to claim 11, characterized in that: The pressure-proof pad is an adhesive tape, which comprises a backing layer, one side of which is coated with adhesive, and the material of the backing layer is selected from: paper, polymer film, cloth, and metal foil.

14. The shingled assembly according to claim 6 or 7, characterized in that: The first electrode is composed of a pad and a gate line connecting adjacent pads, and the first electrical connector is conductively connected to the pad of the first electrode; and / or, The second electrode is composed of a pad and a gate line connecting adjacent pads, and the second electrical connection body is conductively connected to the pad of the second electrode.

15. The shingled assembly according to claim 6 or 7, characterized in that: One end of the back contact solar cell is provided with a chamfer, and the other end is not provided with a chamfer; In the shingled assembly, an end of a back-contact solar cell that is not chamfered is overlapped and arranged on an end of another back-contact solar cell that is chamfered.

16. The shingled assembly according to claim 6 or 7, characterized in that: Also included are: a cover plate located on the light-facing side of the back-contact solar cell, and a back plate located on the backlight-receiving side of the back-contact solar cell; A sealing layer is also provided between the cover plate and the back plate and around the back contact solar cell; the material of the sealing layer is selected from at least one of ethylene / vinyl acetate copolymer, ethylene / α-olefin copolymer, polyvinyl butyl ester, acrylic resin, polyurethane resin, and silicone resin.

17. The shingled assembly according to claim 16, characterized in that: Also includes: A front anti-reflection layer located on the light-facing surface of the cover plate; The light-facing surface and / or the backlight surface of the cover plate has a light-trapping structure.

18. A method for preparing a shingled assembly, characterized in that: The steps include: Providing a conductive interconnection member of a shingled assembly as claimed in any one of claims 1 to 5; Laying at least two overlapping back-contact solar cells on the conductive interconnect to obtain a component precursor, so that a first electrical connector in the conductive interconnect is opposite to a first electrode of the back-contact solar cell, and a second electrical connector is opposite to a second electrode of the back-contact solar cell; the first electrode and the second electrode have opposite polarities; A stack including the assembly precursor is laminated such that the first electrode is conductively connected to the conductive trace of the conductive interconnect through the first electrical connector, and the second electrode is conductively connected to the conductive trace of the conductive interconnect through the second electrical connector.

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