METHODS FOR MANUFACTURING PHOTOELECTRIC MODULES AND PHOTOELECTRIC MODULES

Abstract

The invention relates to a method for the manufacture of photovoltaic modules and photovoltaic modules. This method includes: fitting a pre-packaging structure, a photovoltaic cell and a base plate, the pre-packaging structure comprising a cover plate and a packing layer; making an insulating layer and making through-holes on the surface of at least one side of the photovoltaic cell, such that the location of the through-holes corresponds to the electrode lines of the photovoltaic cell; making a conductive layer on the base plate; applying a conductive adhesive to the through-holes and / or on the conductive layer; joining the base plate to the photovoltaic cell such that the insulating layer matches the conductive layer and the conductive adhesive electrically connects the electrode wires and the conductive layer through the through-holes; making a packing layer on one side of the photovoltaic cell away from the base plate; placing a cover plate on one side of the packing layer away from the photovoltaic cell; and laminating the cover plate, packing layer, photovoltaic cell and base plate to form a photovoltaic module.According to the method for manufacturing photovoltaic modules proposed in the invention, the complexity of the photovoltaic module manufacturing process can be reduced, thus making the steps in the process easier to perform.

Description

A method for preparing a photovoltaic module and a photovoltaic module

[0001] This invention claims priority to the Chinese patent application filed with the Patent Office of China on September 5, 2022, with application number 202211075516.3 and application name “A method for preparing a photovoltaic module and a photovoltaic module”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of photovoltaic technology, and in particular to a method for preparing a photovoltaic module and a photovoltaic module. Background Art

[0003] A photovoltaic module typically consists of a front-side encapsulation structure, a back-side encapsulation structure, a photovoltaic cell, an insulating layer, and a conductive layer. The positive and negative grid lines on the photovoltaic cell need to be connected to the conductive layer to form an electrical connection path. The insulating layer is used to insulate the conductive layer from the area on the photovoltaic cell other than the connection points of the positive and negative grid lines.

[0004] The photovoltaic modules in the prior art have high requirements on process precision during preparation, so there is a problem of relatively complicated process steps.

[0005] Summary of the Invention

[0006] The present application provides a method for preparing a photovoltaic module and a photovoltaic module, which can reduce the complexity of the process for preparing the photovoltaic module.

[0007] In a first aspect, the present application provides a method for preparing a photovoltaic module, comprising the following steps:

[0008] Providing a front encapsulation structure, a photovoltaic cell and a back sheet, wherein the front encapsulation structure includes a cover plate and an encapsulation layer;

[0009] Arranging an insulating layer and a through hole on the surface of at least one side of the photovoltaic cell, so that the through hole corresponds to the position of the grid line of the photovoltaic cell;

[0010] providing a conductive layer on the back plate;

[0011] Disposing conductive glue in the through hole and / or on the conductive layer;

[0012] Connecting the back plate to the photovoltaic cell, laminating the insulating layer to the conductive layer, and electrically connecting the gate line and the conductive layer through the conductive adhesive via the through hole;

[0013] Arrange the encapsulation layer on a side of the photovoltaic cell away from the backsheet;

[0014] Arrange the cover plate on a side of the encapsulation layer away from the photovoltaic cell;

[0015] The cover plate, the encapsulation layer, the photovoltaic cell and the back plate are laminated to form the photovoltaic module.

[0016] In one possible design, when an insulating layer and a through hole are provided on the surface of at least one side of the photovoltaic cell, the method for preparing the photovoltaic module specifically includes: printing insulating glue on the surface of at least one side of the photovoltaic cell; curing the insulating glue to form the insulating layer, and forming the through hole in the area on the surface of the photovoltaic cell where the insulating glue is not printed.

[0017] In a possible design, the insulating glue is transparent insulating glue.

[0018] In one possible design, before printing the insulating glue on the surface of at least one side of the photovoltaic cell or curing the insulating glue to form the insulating layer, and after forming the through hole in the area on the surface of the photovoltaic cell where the insulating glue is not printed, the method for preparing the photovoltaic module further includes: performing an electrical performance test on the photovoltaic cell; and / or, after curing the insulating glue to form the insulating layer, and after forming the through hole in the area on the surface of the photovoltaic cell where the insulating glue is not printed, the method for preparing the photovoltaic module further includes: sorting the photovoltaic cells according to their color and appearance.

[0019] In a possible design, the thickness of the insulating layer is D1, the thickness of the conductive adhesive is D2, and 1.2≤D2:D1≤1.5.

[0020] In one possible design, when a conductive layer is provided on the backplane, the method for preparing the photovoltaic module specifically includes: providing a mask plate on the backplane; depositing a transparent metal oxide on the surface of the backplane through the opening of the mask plate to form a metal conductive layer; removing the mask plate, and forming an insulating groove in the area of ​​the backplane where the transparent metal oxide is not deposited.

[0021] In one possible design, after removing the mask plate and forming an insulating groove in the area of ​​the backplane where the transparent metal oxide is not deposited, the method for preparing the photovoltaic module further includes: forming an electrode connection layer on the surface of the metal conductive layer by printing and sintering, and the metal conductive layer and the electrode connection layer together constitute the conductive layer.

[0022] In a possible design, the back panel material is one of glass, polycarbonate, and polyethylene terephthalate.

[0023] In one possible design, the backplane material is one of polyvinyl fluoride, ethylene-tetrafluoroethylene copolymer, and polyvinylidene fluoride, and before laminating the cover plate, the encapsulation layer, the photovoltaic cell and the backplane to form the photovoltaic module, the method for preparing the photovoltaic module further includes: flipping the cover plate, the encapsulation layer, the photovoltaic cell and the backplane as a whole so that the cover plate is at the bottom and the backplane is at the top.

[0024] A second aspect of the present application provides a photovoltaic module, which is prepared using the above-mentioned preparation method. Along the thickness direction of the photovoltaic module, the photovoltaic module comprises:

[0025] a back plate, wherein a conductive layer is provided on the back plate;

[0026] A photovoltaic cell, comprising a grid line, wherein a surface of at least one side of the photovoltaic cell is provided with an insulating layer and a through hole, wherein the through hole corresponds to the position of the grid line;

[0027] Conductive glue is located in the through hole, and two ends of the conductive glue are respectively connected to the conductive layer and the gate line;

[0028] an encapsulation layer, covering a side of the photovoltaic cell away from the backsheet;

[0029] A cover plate covers the side of the packaging layer away from the photovoltaic cell, and the cover plate and the back plate jointly clamp the packaging layer and the photovoltaic cell.

[0030] In one possible design, the conductive layer includes a metal conductive layer and an electrode connection layer, and the electrode connection layer is arranged on the side surface of the metal conductive layer close to the photovoltaic cell; one end of the conductive glue is connected to the positive or negative pole of the photovoltaic cell, and the other end is connected to the electrode connection layer.

[0031] In one possible design, the material of the electrode connection layer is one or more of Au, Ag, Cu, Al, Bi, Sn, and Pb.

[0032] In one possible design, an insulating groove is formed on the back plate, and the conductive layer is arranged around the insulating groove;

[0033] The region where the electrode connection layer is connected to the positive electrode of the photovoltaic cell and the region where the electrode connection layer is connected to the negative electrode of the photovoltaic cell are located on both sides of the insulating groove.

[0034] The method for preparing a photovoltaic module provided in the present application directly arranges the insulating layer on the surface of the photovoltaic cell, which can reduce the process complexity of preparing the photovoltaic module, and can also improve the position accuracy of the through-hole, ensuring that it is opened at a position corresponding to the grid line, thereby reducing the risk of poor contact of the conductive adhesive due to misalignment between the through-hole and the grid line. In the lamination process, it can also reduce the risk of poor contact and short circuit caused by the position change of the conductive adhesive due to misalignment between the insulating layer and the photovoltaic cell during the lamination process. At the same time, the conductive layer is also directly arranged on the surface of the backplane, which can also reduce the risk of poor contact caused by misalignment of the conductive adhesive.

[0035] It should be understood that the foregoing general description and the following detailed description are merely illustrative and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] FIG1 is a schematic diagram of the structure of a photovoltaic module provided in this application;

[0037] FIG2 is a flow chart of preparing a photovoltaic module provided in this application;

[0038] FIG3 is a schematic structural diagram of one side surface of a photovoltaic cell;

[0039] FIG4 is a flow chart of preparing a photovoltaic module provided in this application;

[0040] FIG5 is a flow chart of preparing a photovoltaic module provided in this application;

[0041] FIG6 is a flow chart of preparing a photovoltaic module provided in this application;

[0042] FIG7 is a schematic diagram of the cross-sectional structure of a photovoltaic module;

[0043] FIG8 is a schematic diagram of the cross-sectional structure of a photovoltaic cell;

[0044] FIG9 is a flow chart of preparing a photovoltaic module provided in this application;

[0045] FIG10 is a flow chart of preparing a photovoltaic module provided in this application;

[0046] FIG11 is a schematic structural diagram of a backplane;

[0047] FIG12 is a flow chart of preparing a photovoltaic module provided in this application.

[0048] Figure 1: 1-backplane; 11-conductive layer; 111-metal conductive layer; 112-electrode connection layer; 113-insulating groove; 2-photovoltaic cell; 20-gate line; 21-insulating layer; 211-through hole; 3-conductive adhesive; 4-encapsulation layer; 5-cover plate.

[0049] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application. DETAILED DESCRIPTION

[0050] In order to better understand the technical solution of the present application, the embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0051] It should be clear that the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0052] The terms used in the embodiments of the present application are for the purpose of describing specific embodiments only and are not intended to limit the present application. The singular forms "a", "an", "the" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms unless the context clearly indicates otherwise.

[0053] It should be understood that the term "and / or" as used herein is merely a description of the relationship between associated objects, indicating that three possible relationships exist. For example, "A and / or B" can represent: A exists alone, A and B exist simultaneously, or B exists alone. Furthermore, the character " / " in this document generally indicates that the associated objects are in an "or" relationship.

[0054] It should be noted that the directional words such as "upper", "lower", "left", and "right" described in the embodiments of the present application are described based on the angles shown in the accompanying drawings and should not be understood as limiting the embodiments of the present application. In addition, in the context, it should be understood that when it is mentioned that an element is connected to another element "on" or "under", it can not only be directly connected to the other element "on" or "under", but also be indirectly connected to the other element "on" or "under" through an intermediate element.

[0055] The existing method for preparing photovoltaic modules usually sets the insulating layer and the conductive layer separately, and then laminates and assembles the photovoltaic cells, the insulating layer, the conductive layer and the backplane. The process is complicated and easily causes poor contact between the photovoltaic cells and the backplane.

[0056] To this end, an embodiment of the present application provides a method for preparing a photovoltaic module, as shown in Figures 1 and 2, the method comprising the following steps:

[0057] Step S1: providing a front packaging structure, a photovoltaic cell 2 and a back plate 1 , wherein the front packaging structure includes a cover plate 5 and a packaging layer 4 .

[0058] As shown in Figure 1, a photovoltaic module consists of a cover sheet 5, an encapsulation layer 4, photovoltaic cells 2, and a backsheet 1, which are laminated and encapsulated to form a photovoltaic module suitable for long-term outdoor use. This encapsulation process ensures the photovoltaic cells 2 have good mechanical strength, mitigating the effects of hail, wind, and mechanical vibration. It also improves the sealing of the photovoltaic cells 2, enhancing their corrosion resistance and safety.

[0059] Step S2 : providing an insulating layer 21 and a through hole 211 on at least one side of the photovoltaic cell 2 , such that the through hole 211 is aligned with the gate line 20 of the photovoltaic cell 2 .

[0060] As shown in Figure 3, the surface of the photovoltaic cell 2 is covered with an insulating layer 21, which can prevent the positive and negative grid lines of the photovoltaic cell 2 from being connected and causing a short circuit. A plurality of through holes 211 are formed at positions corresponding to the grid lines 20 of the photovoltaic cell 2 on the insulating layer 21. The through holes 211 are used to achieve electrical connection between the photovoltaic cell 2 and the backplane 1. Compared with the prior art of separately setting the insulating layer 21 and then connecting it to the photovoltaic cell 2, this embodiment directly sets the insulating layer 21 on the surface of the photovoltaic cell 2, which can reduce the process complexity of the photovoltaic module, eliminate the layout link of the insulating layer 21, make the process steps simpler, and also reduce the preparation cost of the photovoltaic module. In the subsequent lamination process, it can also reduce the risk of misalignment between the insulating layer 21 and the photovoltaic cell 2 during the lamination process, which causes the position of the conductive adhesive 3 to change, resulting in poor contact and short circuit.

[0061] In addition, directly setting the insulating layer 21 on the surface of the photovoltaic cell 2 can also improve the adhesion between the insulating layer 21 and the photovoltaic cell 2, which is beneficial to improving the insulation effect of the insulating layer 21, thereby improving the electrical insulation of the photovoltaic module, and further increasing the service life and safety of the photovoltaic module.

[0062] Specifically, the insulating layer 21 and the through hole 211 can be simultaneously produced by screen printing or mask printing, or the insulating layer 21 can be coated on the entire surface of the photovoltaic cell 2 first, and then a portion of the insulating layer 21 at the position corresponding to the gate line 20 is removed to form the through hole 211.

[0063] The photovoltaic cell 2 in the present application may be a whole cell or a plurality of cells connected in series or in parallel.

[0064] Step S3: providing a conductive layer 11 on the back plate 1 .

[0065] Compared with the prior art in which a conductive layer 11 is separately provided and then connected to the backboard 1 and the photovoltaic cell 2 , this embodiment directly provides the conductive layer 11 on the surface of the backboard 1 , which can further reduce the process complexity of the photovoltaic module.

[0066] Step S4 : Disposing a conductive adhesive 3 in the through hole 211 and / or on the conductive layer 11 .

[0067] The conductive adhesive 3 is disposed in the through hole 211 and / or on the conductive layer 11 . The conductive adhesive 3 is used to achieve electrical connection between the positive and negative grid lines of the photovoltaic cell 2 and the conductive layer 11 .

[0068] Step S5 : connecting the back plate 1 to the photovoltaic cell 2 , laminating the insulating layer 21 to the conductive layer 11 , and electrically connecting the gate line 20 to the conductive layer 11 through the conductive adhesive 3 via the through hole 211 .

[0069] When the photovoltaic cell 2 is connected to the backboard 1 , the conductive adhesive 3 electrically connects the grid line 20 to the conductive layer 11 through the through hole 211 , which can improve the electrical connection stability of the photovoltaic module and thus improve the yield rate of the photovoltaic module.

[0070] Step S6 : disposing the encapsulation layer 4 on the side of the photovoltaic cell 2 away from the back sheet 1 .

[0071] The encapsulation layer 4 is used to protect the photovoltaic cell 2 from the side of the backsheet 1 and to bond the cover plate 5, photovoltaic cell 2, and backsheet 1 into a single unit. The encapsulation layer 4 can be made of a material such as ethylene-vinyl acetate copolymer (EVA), polyolefin elastomer (POE), or polyvinyl butyral (PVB). Its thickness should be greater than 300 μm to meet the encapsulation requirements of the photovoltaic module. Preferably, the thickness of the encapsulation layer 4 is 400 to 800 μm, which ensures good mechanical strength for the photovoltaic module and helps improve the yield and reliability of the photovoltaic module.

[0072] Step S7 : placing the cover plate 5 on the side of the encapsulation layer 4 away from the photovoltaic cell 2 .

[0073] The cover plate 5, located at the topmost layer of the photovoltaic module, is used to transmit sunlight, improve the module's waterproof and moisture-proof capabilities, and, together with the backsheet 1, seal the photovoltaic cells 2. The cover plate 5 can be made of a rigid material such as tempered glass, polyethylene terephthalate (PET), or polycarbonate (PC), or a flexible material such as polyvinyl fluoride (PVF), ethylene-tetrafluoroethylene copolymer (ETFE), or polyvinylidene fluoride (PVDF). These materials have high light transmittance, ensuring that more light reaches the surface of the photovoltaic cells 2, thereby increasing the photovoltaic module's light absorption.

[0074] Step S8: laminating the cover plate 5, the encapsulation layer 4, the photovoltaic cell 2 and the back plate 1 to form a photovoltaic module.

[0075] Lamination is to bond and fuse the various components of the photovoltaic module together under certain temperature, pressure and vacuum conditions, thereby protecting the photovoltaic cells 2.

[0076] The method for preparing a photovoltaic module provided in the present application sets the insulating layer 21 directly on the surface of the photovoltaic cell 2, which can reduce the complexity of the process for preparing the photovoltaic module, and can also improve the position accuracy of the through hole 211, ensuring that it is opened at a position corresponding to the grid line 20, thereby reducing the risk of poor contact of the conductive adhesive 3 due to the misalignment of the through hole 211 and the grid line 20. In the lamination process, it can also reduce the risk of poor contact and short circuit caused by the position change of the conductive adhesive 3 due to the misalignment of the insulating layer 21 and the photovoltaic cell 2 during the lamination process. At the same time, the conductive layer 11 is also directly set on the surface of the backplane 1, which can also reduce the risk of poor contact caused by the misalignment of the conductive adhesive 3.

[0077] It should be noted that the photovoltaic cell 2 has two side surfaces arranged opposite to each other, specifically the light-facing surface and the backlight surface of the photovoltaic cell 2. The light-facing surface refers to the side surface of the photovoltaic cell 2 facing the light source and used to receive direct sunlight, and the backlight surface refers to the side surface of the photovoltaic cell 2 facing away from the light source and used to receive sunlight reflected from the ground.

[0078] Specifically, in this embodiment, providing an insulating layer 21 and a through-hole 211 on the surface of at least one side of the photovoltaic cell 2 means providing the insulating layer 21 and the through-hole 211 on the backlight side, or providing the insulating layer 21 and the through-hole 211 on both the light-facing side and the backlight side. Preferably, the photovoltaic cell 2 is a back-contact cell. Compared with conventional solar cells, both the positive and negative grid lines are provided on the backlight side of the photovoltaic cell 2, and no metal grid lines are provided on the light-facing side. This can reduce the obstruction of sunlight, increase the light-receiving area of ​​the photovoltaic cell 2, and thus improve the photoelectric conversion efficiency of the photovoltaic module. Moreover, when the photovoltaic cell 2 is a back-contact cell, the insulating layer 21 and the through-hole 211 only need to be provided on the backlight side, which can also reduce the production cost of the photovoltaic module.

[0079] In addition, this embodiment does not limit the shape of the gate line 20 , which may be a through-type, segmented gate line or a dot-shaped electrode point.

[0080] In a specific embodiment, as shown in FIG4 , for step S2: providing an insulating layer 21 and a through hole 211 on the surface of at least one side of the photovoltaic cell 2, the method for preparing the photovoltaic module specifically includes:

[0081] Step A1: Printing insulating glue on at least one side of the photovoltaic cell 2 .

[0082] Printing the insulating adhesive can be done by screen printing, where a template with a pattern is attached to the screen for printing. The photovoltaic cell 2 is placed under the screen with the template, and the insulating adhesive is squeezed by a scraper through the mesh holes in the middle of the screen and printed on the surface of the photovoltaic cell 2. Since the template on the screen seals a portion of the screen holes, the insulating adhesive cannot pass through. Therefore, only the positions corresponding to the image on the screen are coated with insulating adhesive on the surface of the photovoltaic cell 2, while through holes 211 are formed in the remaining positions. Specifically, at the positions on the screen template corresponding to the grid lines 20, a portion of the screen holes are sealed to ensure the accurate positioning of the through holes 211. The thickness of the screen is 10 to 200 μm, and the thickness of the printed insulating adhesive is 15 to 300 μm to ensure that the insulating layer 21 finally formed has a good insulating effect.

[0083] In addition, printed insulating adhesive can also be printed using a mask printing method, using a mask plate with a printed pattern for printing. The principle and effect are similar to those of screen printing, so they will not be described here.

[0084] Step A2: curing the insulating adhesive to form an insulating layer 21 , and forming through holes 211 in the areas on the surface of the photovoltaic cell 2 where the insulating adhesive is not printed.

[0085] After the insulating adhesive is printed on the photovoltaic cell 2, it enters the curing process to form the insulating layer 21. A high-temperature curing process is generally used, with a curing temperature of 100°C to 200°C to prevent the insulating adhesive from failing due to excessive temperatures. The curing time should be controlled to ≤ 10 minutes to improve the production efficiency of the photovoltaic module.

[0086] Specifically, the insulating glue in this embodiment preferentially covers the entire surface of the photovoltaic cell 2 except the through hole 211. During the lamination process, the insulating glue not only has an insulating effect, but also can play a buffering role for the photovoltaic cell 2 and the backboard 1, thereby reducing the lamination fragmentation rate and improving the yield rate of the photovoltaic module.

[0087] In addition, the insulating adhesive can be partially cured during the curing process, maintaining a certain degree of viscosity. When the photovoltaic cell 2 is connected to the backsheet 1, the insulating adhesive can connect the photovoltaic cell 2 and the backsheet 1, achieving a temporary fixation effect. In subsequent processes, there is no need to temporarily fix the photovoltaic cell 2 and the backsheet 1, further simplifying the process steps for preparing the photovoltaic module. The insulating adhesive is fully cured during the lamination process.

[0088] In a specific embodiment, the insulating adhesive is a transparent insulating adhesive.

[0089] The insulating glue can be one or more of silicone, acrylic and epoxy resins. Its viscosity before curing is 0-50 Pa·s, and its transmittance after curing can reach more than 75%, so that the backlight side of the photovoltaic cell 2 maintains a high transmittance, thereby receiving more light reflected from the ground into the photovoltaic module, which is conducive to realizing double-sided power generation of the photovoltaic module.

[0090] In a specific embodiment, as shown in FIG5 and FIG6, before step A1 or after step A2, the method for preparing a photovoltaic module further includes:

[0091] Step A0: Conducting an electrical performance test on the photovoltaic cell 2 .

[0092] Due to the random nature of cell manufacturing conditions, the performance of photovoltaic cells 2 varies from one cell to another. To effectively group photovoltaic cells 2 with consistent or similar performance, they should be classified according to their performance parameters. Testing photovoltaic cells 2 can improve utilization and produce high-quality photovoltaic modules. Electrical performance testing primarily examines the basic characteristics of photovoltaic cells 2 to determine their outdoor power generation capabilities.

[0093] In this embodiment, the electrical performance test can be performed before or after the process of setting the insulating layer 21 and the through hole 211. During the test, the position of the test tool pressure needle should be consistent with the position of the through hole 211 to ensure the accuracy of the test results.

[0094] And / or, after step A2, the method for preparing a photovoltaic module further comprises:

[0095] Step A3: Sorting the photovoltaic cells 2 according to their color and appearance.

[0096] After the process of setting the insulating layer 21 and the through hole 211, the color and appearance of the photovoltaic cell 2 need to be sorted, mainly by visual inspection, to inspect the thickness, defects, flatness, etc. of the photovoltaic cell 2. At the same time, the color of the photovoltaic cell 2 should remain uniform without obvious color difference.

[0097] In a specific embodiment, as shown in Figures 7 and 8, the thickness of the insulating layer 21 is D1, the thickness of the conductive adhesive 3 is D2, and 1.2≤D2:D1≤1.5. Specifically, D2:D1 can be 1.2, 1.3, 1.4, 1.5, etc.

[0098] In this embodiment, the thickness D2 of the conductive adhesive 3 is greater than the thickness D1 of the insulating layer 21, but should not be too large or too small. Specifically, the thickness D2 of the conductive adhesive 3 and the thickness D1 of the insulating layer 21 should satisfy 1.2≤D2:D1≤1.5. When D2:D1 is too large (e.g., greater than 1.5), the amount of conductive adhesive 3 used increases, resulting in an increase in the production cost of the photovoltaic module, but the conductive effect of the conductive adhesive 3 is not significantly improved. When D2:D1 is too small (e.g., less than 1.2), the thickness D2 of the conductive adhesive 3 is close to the thickness D1 of the insulating layer 21, and the amount of conductive adhesive 3 used is insufficient to fill the through hole 211, and it is impossible to ensure that the conductive adhesive 3 can stably connect the gate line 20 and the conductive layer 11.

[0099] As shown in the table below, when the value of D2:D1 is different, the basic situation of the finished photovoltaic module is as follows:

[0100] In addition, the conductive adhesive 3 can be directly applied into the through hole 211 by dispensing, or printed on the position of the conductive layer 11 corresponding to the through hole 211 by printing.

[0101] In a specific embodiment, as shown in FIG9 , for step S3: providing a conductive layer 11 on the backsheet 1 , the method for preparing a photovoltaic module specifically includes:

[0102] Step B1: Set a mask plate on the back plate 1.

[0103] The mask plate with the pattern is tightly attached to the surface of the back plate 1 to indicate the area where the conductive layer 11 needs to be provided.

[0104] Among them, the back sheet 1 is made of a material with high light transmittance, which can further improve the bifacial power generation capability of the photovoltaic module.

[0105] Step B2: depositing a transparent metal oxide on the surface of the back plate 1 through the openings of the mask plate to form a metal conductive layer 111 .

[0106] A transparent metal oxide is deposited on the surface of the backsheet 1 by physical and / or chemical methods to form a metal conductive layer 111 having a thickness of 10 to 100 μm. The transparent metal oxide can be one or more of In2O3, SnO2, ZnO, CdO, CdIn2O4, Cd2SnO4, Zn2SnO4, and In2O3-ZnO. The transparent metal conductive layer 111 ensures that more light reflected from the ground reaches the backlight side of the photovoltaic cell 2, facilitating bifacial power generation of the photovoltaic module.

[0107] Step B3: removing the mask plate, and forming an insulating groove 113 in the area of ​​the back plate 1 where the transparent metal oxide is not deposited.

[0108] As shown in Figure 11, transparent metal oxide is not deposited in the area on the surface of the backplane 1 blocked by the mask plate, so an insulating groove 113 is formed, which can insulate and isolate the area where the metal conductive layer 111 is connected to the positive electrode of the photovoltaic cell 2 and the area where the metal conductive layer 111 is connected to the negative electrode of the photovoltaic cell 2 to prevent short circuit.

[0109] In a specific embodiment, as shown in FIG10 , after step B3, the method for preparing a photovoltaic module further includes:

[0110] Step B4: forming an electrode connection layer 112 on the surface of the metal conductive layer 111 by printing and sintering. The metal conductive layer 111 and the electrode connection layer 112 together constitute the conductive layer 11 .

[0111] The provision of the electrode connection layer 112 can improve the electrical connection stability between the metal conductive layer 111 and the grid lines 20, reducing the risk of poor contact in the photovoltaic module. Specifically, the electrode connection layer 112 is formed by printing and sintering a slurry containing a highly conductive material so that the electrode connection layer 112 can be firmly attached to the metal conductive layer 111.

[0112] This embodiment does not limit the specific structure of the electrode connection layer 112 , which may be a linear, dot-shaped or other structure.

[0113] In a specific embodiment, as shown in FIG12 , the material of the back sheet 1 is one of polyvinyl fluoride, ethylene-tetrafluoroethylene copolymer, and polyvinylidene fluoride, and before step S7, the method for preparing the photovoltaic module further includes:

[0114] Step C2: Turn over the cover plate 5, the encapsulation layer 4, the photovoltaic cell 2 and the back plate 1 as a whole, so that the cover plate 5 is at the bottom and the back plate 1 is at the top.

[0115] The material of the backboard 1 is a flexible material. In order to prevent the flexible material from coming into contact with the loading table and causing deformation and cracking during the lamination process, before the lamination process, the cover plate 5, the encapsulation layer 4, the photovoltaic cell 2 and the backboard 1 need to be flipped over as a whole so that the cover plate 5 is at the bottom and the backboard 1 is at the top. The flipped photovoltaic module is then placed on the loading table of the laminator, thereby avoiding damage to the backboard 1 during the lamination process and improving the yield rate of the photovoltaic module.

[0116] In addition, polyvinyl fluoride (PVF), ethylene-tetrafluoroethylene copolymer (ETFE), and polyvinylidene fluoride (PVDF) are all transparent materials with high light transmittance of 0.2mm to 6mm, which can ensure that more light reflected from the ground reaches the backlight surface of the photovoltaic cell 2, which is conducive to the realization of double-sided power generation of the photovoltaic module.

[0117] In another specific embodiment, the back plate 1 is made of one of glass, polycarbonate, and polyethylene terephthalate.

[0118] In this embodiment, the material of the backboard 1 is a rigid material. When performing the lamination process, there is no need to flip the photovoltaic module as a whole. It can be placed directly on the loading table of the laminator. At this time, the backboard 1 is in contact with the loading table. Due to its high hardness, it will not be deformed or broken during the lamination process. Compared with the backboard 1 made of flexible material, the backboard 1 of this embodiment can reduce the complexity of the process, eliminate the flipping step before lamination, and reduce the risk of adverse reactions in the preparation process of the photovoltaic module.

[0119] In addition, glass, polycarbonate (PC), and polyethylene terephthalate (PET) are all transparent materials with high light transmittance. Their thickness is 0.2 mm to 6 mm, which can ensure that more light reflected from the ground reaches the backlight surface of the photovoltaic cell 2, which is conducive to achieving double-sided power generation of the photovoltaic module.

[0120] The present application also provides a photovoltaic module, which is prepared using the preparation methods described in the above embodiments. As shown in Figures 1, 3, and 7, along the thickness direction X of the photovoltaic module, the photovoltaic module includes: a backsheet 1, a photovoltaic cell 2, a conductive adhesive 3, an encapsulation layer 4, and a cover plate 5. The backsheet 1 is provided with a conductive layer 11; the photovoltaic cell 2 includes a grid line 20, and the surface of at least one side of the photovoltaic cell 2 is provided with an insulating layer 21 and a through hole 211, with the through hole 211 corresponding to the position of the grid line 20; the conductive adhesive 3 is located in the through hole 211, and the two ends of the conductive adhesive 3 are respectively connected to the conductive layer 11 and the grid line 20; the encapsulation layer 4 covers the side of the photovoltaic cell 2 away from the backsheet 1; the cover plate 5 covers the side of the encapsulation layer 4 away from the photovoltaic cell 2, and the cover plate 5 and the backsheet 1 jointly clamp the encapsulation layer 4 and the photovoltaic cell 2.

[0121] In this embodiment, the surface of the photovoltaic cell 2 is covered with an insulating layer 21, which insulates the grid lines 20 from the conductive layer 11, preventing the positive and negative grid lines of the photovoltaic cell 2 from connecting and causing a short circuit. A plurality of through-holes 211 are formed in the insulating layer 21 at positions corresponding to the grid lines 20 of the photovoltaic cell 2. When the photovoltaic cell 2 is connected to the backsheet 1, the conductive adhesive 3 is disposed within the through-holes 211 and / or on the conductive layer 11, so that the conductive adhesive 3 passes through the through-holes 211 to electrically connect the grid lines 20 to the conductive layer 11. This improves the electrical connection stability of the photovoltaic module, thereby increasing the yield rate of the photovoltaic module.

[0122] This embodiment disposes the insulating layer 21 directly on the surface of the photovoltaic cell 2 and the conductive layer 11 directly on the surface of the backsheet 1. This reduces the complexity of the photovoltaic module process and eliminates the layout of the insulating layer 21 and the conductive layer 11, making the process steps simpler. It also reduces the risk of poor contact of the conductive adhesive 3 due to misalignment between the through-hole 211 and the grid line 20. During the lamination process, it also reduces the risk of misalignment between the insulating layer 21 and the photovoltaic cell 2 during the lamination process, which could cause the position of the conductive adhesive 3 to change, resulting in poor contact and short circuits.

[0123] Specifically, as shown in Figure 11, the conductive layer 11 includes a metal conductive layer 111 and an electrode connection layer 112. The electrode connection layer 112 is arranged on the side surface of the metal conductive layer 111 close to the photovoltaic cell 2; one end of the conductive glue 3 is connected to the positive or negative pole of the photovoltaic cell 2, and the other end is connected to the electrode connection layer 112.

[0124] As shown in Figure 2, a plurality of grid lines 20 are arranged at intervals on the surface of the photovoltaic cell 2, and the grid lines 20 include positive grid lines and negative grid lines. The through holes 211 expose part of the positive grid lines, and the conductive glue 3 connects the area with the conductive layer 11 in the through holes 211, so as to achieve the purpose of electrically connecting the positive electrode of the photovoltaic cell 2 with the conductive layer 11; similarly, the through holes 211 expose part of the negative grid lines, and the conductive glue 3 connects the area with the conductive layer 11 in the through holes 211, so as to achieve the purpose of electrically connecting the negative electrode of the photovoltaic cell 2 with the conductive layer 11.

[0125] Specifically, the conductive layer 11 includes a metal conductive layer 111 and an electrode connection layer 112. The electrode connection layer 112 is firmly attached to the metal conductive layer 111 to improve the electrical connection stability between the metal conductive layer 111 and the gate line 20 and reduce the risk of poor contact of the photovoltaic module.

[0126] In a specific embodiment, the material of the electrode connection layer 112 is one or more of Au, Ag, Cu, Al, Bi, Sn, and Pb.

[0127] In this embodiment, Au, Ag, Cu, Al, Bi, Sn, and Pb all have strong conductivity. One or more of the above materials are selected to be made into a highly conductive paste, which is then printed onto the metal conductive layer 111 and sintered to form the electrode connection layer 112. This can ensure that the conductive layer 11 has a good conductive effect and avoid poor contact of the photovoltaic module.

[0128] In a specific embodiment, as shown in Figure 11, an insulating groove 113 is formed on the backboard 1, and the conductive layer 11 is arranged around the insulating groove 113; the area where the electrode connecting layer 112 is connected to the positive pole of the photovoltaic cell 2 and the area where the electrode connecting layer 112 is connected to the negative pole of the photovoltaic cell 2 are located on both sides of the insulating groove 113.

[0129] In this embodiment, the insulating groove 113 is formed on the conductive layer 11, which can insulate and isolate the area where the metal conductive layer 111 is connected to the positive pole of the photovoltaic cell 2 and the area where the metal conductive layer 111 is connected to the negative pole of the photovoltaic cell 2, thereby preventing the positive and negative poles of the photovoltaic cell 2 from being connected and causing a short circuit, thereby improving the reliability and safety of the photovoltaic module.

[0130] The above description is merely a preferred embodiment of the present application and is not intended to limit the present application. Various modifications and variations are possible for those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A method for preparing a photovoltaic module, characterized in that: The steps include: Providing a front encapsulation structure, a photovoltaic cell (2) and a back plate (1), wherein the front encapsulation structure comprises a cover plate (5) and an encapsulation layer (4); An insulating layer (21) and a through hole (211) are provided on the surface of at least one side of the photovoltaic cell (2), so that the through hole (211) corresponds to the position of the grid line (20) of the photovoltaic cell (2); Providing a conductive layer (11) on the back plate (1); Providing a conductive adhesive (3) in the through hole (211) and / or on the conductive layer (11); Connecting the back plate (1) to the photovoltaic cell (2), laminating the insulating layer (21) to the conductive layer (11), and electrically connecting the gate line (20) and the conductive layer (11) through the through hole (211) using the conductive adhesive (3); The encapsulation layer (4) is arranged on a side of the photovoltaic cell (2) away from the back sheet (1); The cover plate (5) is arranged on a side of the encapsulation layer (4) away from the photovoltaic cell (2); The cover plate (5), the encapsulation layer (4), the photovoltaic cell (2) and the back plate (1) are laminated to form the photovoltaic module.

2. The method for preparing a photovoltaic module according to claim 1, wherein: When an insulating layer (21) and a through hole (211) are provided on the surface of at least one side of the photovoltaic cell (2), the method for preparing the photovoltaic module specifically comprises: Printing insulating glue on the surface of at least one side of the photovoltaic cell (2); The insulating glue is cured to form the insulating layer (21), and the through hole (211) is formed in the area on the surface of the photovoltaic cell (2) where the insulating glue is not printed.

3. The method for preparing a photovoltaic module according to claim 2, wherein: The insulating glue is transparent insulating glue.

4. The method for preparing a photovoltaic module according to claim 2, wherein: Before printing insulating glue on at least one side of the surface of the photovoltaic cell (2) or curing the insulating glue to form the insulating layer (21), and after forming the through hole (211) in the area on the surface of the photovoltaic cell (2) where the insulating glue is not printed, the method for preparing the photovoltaic module further comprises: performing an electrical performance test on the photovoltaic cell (2); And / or, after the insulating glue is cured to form the insulating layer (21), and the through hole (211) is formed in the area on the surface of the photovoltaic cell (2) where the insulating glue is not printed, the method for preparing the photovoltaic module further comprises: sorting the photovoltaic cells (2) according to their color and appearance.

5. The method for preparing a photovoltaic module according to any one of claims 1 to 4, characterized in that: The thickness of the insulating layer (21) is D1, the thickness of the conductive adhesive (3) is D2, and 1.2≤D2:D1≤1.

5.

6. The method for preparing a photovoltaic module according to any one of claims 1 to 4, characterized in that: When a conductive layer (11) is provided on the back sheet (1), the method for preparing the photovoltaic module specifically comprises: A mask plate is arranged on the back plate (1); Depositing a transparent metal oxide on the surface of the back plate (1) through the opening of the mask plate to form a metal conductive layer (111); The mask plate is removed, and an insulating groove (113) is formed in the area of ​​the back plate (1) where the transparent metal oxide is not deposited.

7. The method for preparing a photovoltaic module according to claim 6, wherein: After the mask plate is removed and the insulating groove (113) is formed in the area of ​​the back plate (1) where the transparent metal oxide is not deposited, the method for preparing the photovoltaic module further comprises: An electrode connection layer (112) is formed on the surface of the metal conductive layer (111) by printing and sintering, and the metal conductive layer (111) and the electrode connection layer (112) together constitute the conductive layer (11).

8. The method for preparing a photovoltaic module according to claim 6, wherein: The back plate (1) is made of one of glass, polycarbonate and polyethylene terephthalate.

9. The method for preparing a photovoltaic module according to claim 6, wherein: The back sheet (1) is made of a material selected from the group consisting of polyvinyl fluoride, ethylene-tetrafluoroethylene copolymer, and polyvinylidene fluoride, and before laminating the cover sheet (5), the encapsulation layer (4), the photovoltaic cell (2), and the back sheet (1) to form the photovoltaic module, the method for preparing the photovoltaic module further comprises: The cover plate (5), the encapsulation layer (4), the photovoltaic cell (2) and the back plate (1) are turned over as a whole, so that the cover plate (5) is at the bottom and the back plate (1) is at the top.

10. A photovoltaic module, characterized in that: The photovoltaic module is prepared by the preparation method according to any one of claims 1 to 9. Along the thickness direction of the photovoltaic module, the photovoltaic module comprises: A back plate (1), wherein a conductive layer (11) is provided on the back plate (1); A photovoltaic cell (2) comprising a grid line (20), wherein a surface of at least one side of the photovoltaic cell (2) is provided with an insulating layer (21) and a through hole (211), wherein the through hole (211) corresponds to the position of the grid line (20); Conductive glue (3) is located in the through hole (211), and two ends of the conductive glue (3) are respectively connected to the conductive layer (11) and the gate line (20); an encapsulation layer (4), covering a side of the photovoltaic cell (2) away from the backsheet (1); A cover plate (5) covers the side of the encapsulation layer (4) away from the photovoltaic cell (2), and the cover plate (5) and the back plate (1) jointly clamp the encapsulation layer (4) and the photovoltaic cell (2).

11. The photovoltaic module according to claim 10, characterized in that: The conductive layer (11) comprises a metal conductive layer (111) and an electrode connection layer (112), wherein the electrode connection layer (112) is arranged on a side surface of the metal conductive layer (111) close to the photovoltaic cell (2); One end of the conductive glue (3) is connected to the positive electrode or the negative electrode of the photovoltaic cell (2), and the other end is connected to the electrode connection layer (112).

12. The photovoltaic module according to claim 11, characterized in that: The material of the electrode connection layer is one or more of Au, Ag, Cu, Al, Bi, Sn, and Pb.

13. The photovoltaic module according to claim 11, characterized in that: An insulating groove (113) is formed on the back plate (1), and the conductive layer (11) is arranged around the insulating groove (113); The region where the electrode connection layer (112) is connected to the positive electrode of the photovoltaic cell (2) and the region where the electrode connection layer (112) is connected to the negative electrode of the photovoltaic cell (2) are located on both sides of the insulating groove (113).

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