Photovoltaic module

Abstract

This application relates to the photovoltaic field and provides a photovoltaic module, including: at least two solar cells; a plurality of connecting members arranged at intervals along a first direction, the connecting members being used to connect adjacent solar cells; a plurality of insulating layers arranged at intervals along the first direction, each insulating layer covering each connecting member, and at least a portion of the insulating layer also being located on the surface of the solar cell along the first direction; an encapsulation layer covering the surface of the insulating layers and the surface of the solar cells; and a cover plate located on the side of the encapsulation layer away from the solar cells; the thickness D of the encapsulation layer satisfies the formula: D = (B + C) - E, where B is the distance between the bottom surface of the connecting member in contact with the solar cell and the top surface of the connecting member near the encapsulation layer; E is the thickness of the insulating layer; and C is the distance between the top surface of the connecting member and the cover plate. The photovoltaic module provided by this application can at least improve the yield of photovoltaic modules.

Description

Technical Field

[0001] This application relates to the photovoltaic field, and in particular to a photovoltaic module. Background Technology

[0002] A solar cell is a device that directly converts light energy into electrical energy through the photoelectric effect or photochemical effect. A single solar cell cannot generate electricity directly. Several individual cells must be connected in series or parallel using solder strips and then tightly sealed to form a module before use. A solar cell module (also called a solar panel) is the core and most important component of a solar power generation system. The function of a solar cell module is to convert solar energy into electrical energy, which can then be either stored in batteries or used to power loads.

[0003] Solar cells are very fragile, and generally require an adhesive film and a cover plate on the top and bottom surfaces of the solar module to protect them. The cover plate is usually made of photovoltaic glass, which cannot be directly attached to the solar cells; an adhesive film is needed in between to act as a bond. Connecting solar cells typically requires solder ribbons for current collection. In conventional solder ribbons, alloying is achieved between the ribbon and the grid during welding. Common solder ribbons include a tin solder layer, composed of 60% tin and 40% lead. The eutectic point temperature of the tin-lead alloy in the phase diagram is around 183°C, meaning the melting point of the tin solder layer in the ribbon is 183°C. However, in actual welding, the welding temperature is more than 20°C higher than the melting point of the solder. Due to significant warping and deformation during welding, solar cells have a high risk of microcracks and a high breakage rate after welding. Especially for PERC cells (Passivated Emitter and Rear Cell), which inherently have high internal stress, warping and breakage are more likely to occur after welding, leading to increased module rework rates and reduced yield. Against this backdrop, low-temperature solder ribbons were developed to improve welding quality. However, many factors still affect module yield, such as welding and the contact resistance between the solder ribbon and the grid. Summary of the Invention

[0004] This application provides a photovoltaic module that at least helps to improve the yield of photovoltaic modules.

[0005] According to some embodiments of this application, one aspect of this application provides a photovoltaic module, including: at least two solar cells; a plurality of connecting members spaced apart along a first direction, the connecting members being used to connect adjacent solar cells; a plurality of insulating layers spaced apart along the first direction, each insulating layer covering each connecting member, and at least a portion of the insulating layer being located on the surface of the solar cell along the first direction; an encapsulation layer covering the surface of the insulating layers and the surface of the solar cells; a cover plate located on the side of the encapsulation layer away from the solar cells; the thickness D of the encapsulation layer satisfies the formula: D = (B + C) - E, where B is the bottom surface of the connecting member in contact with the solar cell, and the distance is the distance between the top surface of the connecting member and the side of the encapsulation layer; E is the thickness of the insulating layer, and C is the distance between the top surface of the connecting member and the cover plate.

[0006] In some embodiments, along the first direction, the ends of both sides of the insulating layer are located on the surface of the battery cell.

[0007] In some embodiments, along the first direction, the width of the isolation layer is greater than or equal to the perimeter of the outer side of the connecting member.

[0008] In some embodiments, the length of the insulating layer is greater than or equal to the length of the connecting member along the arrangement direction of the battery cells.

[0009] In some embodiments, the melting point of the isolation layer is greater than the melting point of the encapsulation layer.

[0010] In some embodiments, the isolation layer is a pre-crosslinked adhesive film, and the degree of crosslinking of the pre-crosslinked adhesive film is 50% to 70%.

[0011] In some embodiments, the material of the isolation layer is the same as the material of the encapsulation layer.

[0012] In some embodiments, the insulating layer is an insulating adhesive layer.

[0013] In some embodiments, the device further includes: a plurality of connecting layers, the connecting layers being spaced apart along the direction in which the connecting member extends, the connecting layers being located between the battery cell and the connecting member.

[0014] In some embodiments, along the first direction, the width of the connecting layer is greater than the width of the connecting member, and the connecting layer surrounds the connecting member at a certain height.

[0015] In some embodiments, along the first direction, the width of the isolation layer ranges from 0.8 to 5 mm; the thickness of the isolation layer ranges from 70 to 300 μm.

[0016] The technical solution provided in this application has at least the following advantages:

[0017] In the photovoltaic module provided in this application embodiment, an isolation layer is formed on the surface of the connecting component. This isolation layer covers the surface of the connecting component, preventing the encapsulation layer from flowing between the connecting component and the solar cell during the lamination process, and even causing electrical insulation issues. The connecting component is connected to two solar cells, and each isolation layer covers each connecting component. This prevents encapsulation material from entering between the grid structure and the connecting component through the edge of the solar cell, further ensuring the safety of the assembly of the solar cell and the connecting component. Furthermore, by reasonably setting the thickness of the isolation layer, it is equivalent to locally thickening the protective layer at the location of the connecting component. This prevents the film thickness on the connecting component from being insufficient to cover the connecting component during subsequent lamination, causing the connecting component to puncture the film and affecting its isolation performance, thus improving the yield of the photovoltaic module. Therefore, the thickness of the film in areas other than the connecting component can be set smaller; that is, the thickness D of the encapsulation layer is equal to the thickness of the conventional film minus the thickness of the isolation layer, reducing the overall weight of the film and thus saving on the cost of manufacturing the photovoltaic module. Attached Figure Description

[0018] One or more embodiments are illustrated by way of example with reference to the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Unless otherwise stated, the drawings in the accompanying drawings do not constitute a limitation on scale. In order to more clearly illustrate the technical solutions in the embodiments of this application or in the conventional art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of a photovoltaic module provided in one embodiment of this application;

[0020] Figure 2 for Figure 1 A schematic diagram of the first type of cross-sectional structure of a photovoltaic module along section a1-a2;

[0021] Figure 3 for Figure 1 A schematic diagram of the first type of cross-sectional structure of a photovoltaic module along section b1-b2;

[0022] Figure 4 This is a schematic diagram of the structure of an isolation layer in a photovoltaic module according to an embodiment of this application;

[0023] Figure 5 This is a schematic diagram of a first structure in a laminated photovoltaic module provided in an embodiment of this application;

[0024] Figure 6 This is a schematic diagram of a second structure in a laminated photovoltaic module provided in one embodiment of this application;

[0025] Figure 7 for Figure 1 A schematic diagram of the second type of cross-sectional structure of a photovoltaic module along section a1-a2;

[0026] Figure 8 for Figure 1 A schematic diagram of the second type of cross-sectional structure of a photovoltaic module along section b1-b2;

[0027] Figure 9 This is a schematic diagram of a connecting component provided in an embodiment of this application;

[0028] Figure 10 A schematic diagram of a third structure in a laminated photovoltaic module provided in one embodiment of this application;

[0029] Figure 11 This is a schematic diagram of a fourth structure in a laminated photovoltaic module provided in one embodiment of this application;

[0030] Figure 12 This is a schematic diagram of a fifth structure in a laminated photovoltaic module provided in an embodiment of this application. Detailed Implementation

[0031] As can be seen from the background technology, the yield of photovoltaic modules using related technologies is poor.

[0032] Analysis revealed that one reason for the poor yield of photovoltaic modules is that sunlight enters the cell from the front, and the metal electrodes on the front block part of the silicon wafer. This portion of the light energy reaching the electrodes cannot be converted into electrical energy. From this perspective, we want the grid lines to be as thin as possible. However, the grid lines are responsible for conducting current. From a resistivity perspective, thinner grid lines result in a smaller conductive cross-sectional area and greater resistance loss. Therefore, the core of the main and sub-grid design is to achieve a balance between light blocking and conductivity. Similarly, the solder ribbons that make electrical contact with the grid lines also need to achieve a balance between light blocking and conductivity. Furthermore, conventional alloying of the solder ribbons and grid lines typically involves radiating heat from the top of the solder ribbon towards the cell at a temperature 20°C higher than the solder ribbon temperature. This high melting temperature of the solder ribbon requires a higher reflow temperature during soldering, which can make the cell prone to thermal warping. Thermal warping of the cell can damage the integrity of the formed solder joints, thus affecting its performance. Thermal warping of the cell can also lead to various solder defects, such as cell breakage, pillow effect, and cold solder joints.

[0033] Furthermore, when low-melting-point metals are used as solder for connecting components, and lamination is employed to alloy the grid structure with the connecting components—for example, in module lamination processes, the pressure and temperature of the laminator help bond the low-melting-point metal to the grid structure—the welding process between the low-melting-point metal and the grid structure can lead to issues such as solder strip misalignment due to the pushing action of the molten adhesive film, or adhesive overflow between the solder strip and the grid, resulting in cell breakage or poor soldering, thus affecting cell performance.

[0034] This application provides a photovoltaic module that forms an isolation layer on the surface of a connecting component. This isolation layer covers the surface of the connecting component, preventing the encapsulation layer from flowing between the connecting component and the solar cell during lamination, and even causing electrical insulation issues. The connecting component connects to two solar cells, and each isolation layer covers each connecting component. This prevents encapsulation material from entering between the grid structure and the connecting component through the edge of the solar cell, further ensuring the safety of the solar cell and connecting component assembly. Furthermore, by appropriately setting the thickness of the isolation layer, it is equivalent to locally thickening the protective layer at the location of the connecting component. This prevents the encapsulation film on the connecting component from being insufficiently thick to cover the connecting component during subsequent lamination, which could cause the connecting component to puncture the encapsulation film, affecting its isolation performance and improving the yield of the photovoltaic module. Therefore, the thickness of the encapsulation film in areas without connecting components can be set smaller; that is, the thickness D of the encapsulation layer is equal to the thickness of a conventional encapsulation film minus the thickness of the isolation layer, reducing the overall weight of the encapsulation film and thus saving on the cost of manufacturing the photovoltaic module.

[0035] The embodiments of this application will now be described in detail with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details have been provided in the embodiments of this application to facilitate a better understanding of the application. However, the technical solutions claimed in this application can be implemented even without these technical details and various variations and modifications based on the following embodiments.

[0036] Figure 1 This is a schematic diagram of a photovoltaic module provided in one embodiment of this application; Figure 2 for Figure 1 A schematic diagram of the first type of cross-sectional structure of a photovoltaic module along section a1-a2; Figure 3 for Figure 1 A schematic diagram of the first type of cross-sectional structure of a photovoltaic module along section b1-b2;

[0037] Figure 4 This is a schematic diagram of the structure of an isolation layer in a photovoltaic module according to an embodiment of this application; Figure 5 This is a schematic diagram of a first structure in a laminated photovoltaic module provided in an embodiment of this application; Figure 6This is a schematic diagram of a second structure in a laminated photovoltaic module provided in one embodiment of this application; Figure 7 for Figure 1 A schematic diagram of the second type of cross-sectional structure of a photovoltaic module along section a1-a2; Figure 8 for Figure 1 A schematic diagram of the second type of cross-sectional structure of a photovoltaic module along section b1-b2; Figure 9 This is a schematic diagram of a connecting component provided in an embodiment of this application; Figure 10 A schematic diagram of a third structure in a laminated photovoltaic module provided in one embodiment of this application; Figure 11 This is a schematic diagram of a fourth structure in a laminated photovoltaic module provided in one embodiment of this application; Figure 12 This is a schematic diagram of a fifth structure in a laminated photovoltaic module provided in an embodiment of this application.

[0038] in, Figure 1 The encapsulation layer and cover plate of the photovoltaic module are not shown, or the encapsulation layer and cover plate are shown in a transparent state to show and illustrate the position and connection relationship between the cells and the connecting components. Figure 2 , Figure 3 , Figures 5 to 8 as well as Figures 10-12 The cross-sectional view in the image only shows the film structure on one side of the solar cell. The film structure on the other side of the solar cell may be the same as or different from the film structure on the corresponding side of the solar cell. Figures 2-3 as well as Figures 7-8 This is a schematic diagram showing a structure where the connecting components and the gate wire structure are not alloyed, as no lamination process has been performed. Figures 5 to 6 as well as Figures 10 to 12 A schematic diagram of the structure of a photovoltaic module formed by lamination.

[0039] refer to Figures 1 to 11 Some embodiments of this application provide a photovoltaic module, including: at least two solar cells 10; a plurality of connecting members 11 arranged at intervals along a first direction Y, the connecting members 11 being used to connect adjacent solar cells 10; a plurality of isolation layers 12 arranged at intervals along the first direction Y, each isolation layer 12 covering each connecting member 11, and at least a portion of the isolation layer 12 being located on the surface of the solar cell 10 along the first direction Y; an encapsulation layer 13 covering the surface of the isolation layers 12 and the surface of the solar cell 10; and a cover plate 14 located on the side of the encapsulation layer 13 away from the solar cell 10, wherein the cover plate 14 may be a front cover plate located on the front of the photovoltaic module, typically photovoltaic glass, or a back cover plate located on the back of the photovoltaic module, typically photovoltaic glass or a backsheet.

[0040] In some embodiments, the solar cell 10 can be a monocrystalline silicon solar cell, a polycrystalline silicon solar cell, an amorphous silicon solar cell, or a multi-component compound solar cell. Specifically, the multi-component compound solar cell can be a cadmium sulfide solar cell, a gallium arsenide solar cell, a copper indium selenide solar cell, or a perovskite solar cell. In some embodiments, the solar cell 10 includes, but is not limited to, any one of PERC cells, PERT cells (Passivated Emitter and Rear Totally-diffused cell), TOPCon cells (Tunnel Oxide Passivated Contact cell), and HIT / HJT cells (Heterojunction Technology). The front side of the solar cell 10 has a first electrode, and the back side opposite the front side has a second electrode. The first electrode and the second electrode have different polarities. Therefore, in the cross-sectional view shown in the figure, the film layer structures on one side of the solar cell 10 are the same as those on the other side.

[0041] In some embodiments, a first electrode is present on a first surface of the battery cell 10, and a second electrode is present on a side opposite to the first surface. The first electrode is either a positive electrode or a negative electrode, and the second electrode is either a positive electrode or a negative electrode. A connecting member 11 connects the first electrode of any battery cell 10 to the second electrode of an adjacent battery cell. This is an embodiment of the present application. Figure 1 The battery cells 10 shown are arranged in sequence with the first surface facing up, the second surface facing up, and the first surface facing up, so that the connecting component 11 does not need to be bent.

[0042] In some embodiments, the battery cells 10 can be arranged with the first surface facing up and the second surface facing down, the connecting parts are designed to be bent, and the insulating layer covers the connecting parts on the surfaces of multiple battery cells. That is, the insulating layer does not cover only one connecting part, but covers the connecting parts on the upper surface or the lower surface of multiple battery cells.

[0043] In some embodiments, the solar cell 10 is an interdigitated back contact (IBC) crystalline silicon solar cell. An IBC cell is a back-junction back-contact solar cell structure in which the positive and negative metal electrodes are arranged in an interdigitated manner on the back surface of the cell. Its PN junction and electrodes are located on the back of the cell, that is, the electrodes of the emitter region and the base region of the IBC cell are both on the back, and there is no grid line obstruction on the front, which can improve the photoelectric conversion performance of the cell. Therefore, the film layer structure on one side of the solar cell 10 in the cross-sectional view shown in the figure is different from the film layer structure on the other side of the solar cell 10. The film layer structure of the solar cell 10 includes an encapsulation layer 13 and a cover plate 14.

[0044] The solar cell 10 can be a whole cell or a sliced ​​cell. A sliced ​​cell refers to a cell formed by cutting a complete whole cell. Cutting processes include: Laser grooving + cutting (Linear Spectral Clustering, LSC) and Thermal Stress Cell Separation (TMC). In some embodiments, the sliced ​​cell is a half cell, which can also be understood as a halved cell or a two-part cell. In some embodiments, the sliced ​​cell can be a three-part cell, a four-part cell, or an eight-part cell, etc. The function of the halved cell module is to increase power generation by reducing resistance loss. According to Ohm's law, the interconnection power loss of solar cells is proportional to the square of the current. After cutting the cell in half, the current is also reduced by half, and the power loss is reduced to one-quarter of that of a full-size cell. Increasing the number of cells will also increase the number of cell gaps. Through reflection from the module backsheet, the cell gaps help to increase the short-circuit current. In addition, the halved cell module can optimize the width of the cell solder strip. Conventionally, an optimization balance needs to be struck between increasing the solder strip width to reduce power loss and decreasing the solder strip width to reduce shading loss. By cutting the battery into half, battery losses are reduced, and the width of the solder strip can be set to be thinner to reduce shading losses, which is beneficial to improving battery efficiency and power generation.

[0045] In some embodiments, two battery cells 10 are connected in series or in parallel through a connecting member 11 to form a battery string, with battery gaps between the battery cells to achieve electrical insulation between different battery cells 10.

[0046] In some embodiments, the grid structure 101 is used to collect the photocurrent generated within the solar cell and lead it to the outside of the cell 10. The grid structure 101 is an auxiliary grid line, also known as a sub-grid line, used to guide current. In some embodiments, the grid structure 101 includes only auxiliary grid lines, i.e., the cell 10 has a gridless design, thereby shortening the carrier transport path and reducing the series resistance, thus increasing the front-side light-receiving area, improving module power, and helping to increase short-circuit current, thereby reducing the amount of silver paste used for grid line printing and reducing production costs.

[0047] In some embodiments, the connecting component 11 is a solder ribbon, which is used for interconnecting the solar cells 10 and collecting current to transmit it to components outside the photovoltaic module. The solder ribbon includes bus solder ribbon and interconnect solder ribbon. The bus solder ribbon is used to connect the photovoltaic cell string and the junction box, and the interconnect solder ribbon is used to connect the solar cells 10 to each other.

[0048] In some embodiments, reference Figure 9 , Figure 9This is the initial state of the connecting component 11 before welding or lamination. The connecting component 11 includes a body portion 113 and a coating 114 covering the surface of the body portion 113. The body portion 113 is a conductive layer with a certain strength and good conductivity. This conductive layer serves as the main conductive transport layer for the connecting component 11. Therefore, the lower the resistivity of the body portion 113, the smaller the electrical loss of the connecting component 11, and the better the battery efficiency and power generation. The coating 114 can be plated or coated on the surface of the body portion 113. Specifically, it can be applied using special processes such as electroplating, vacuum deposition, spraying, or hot-dip coating to uniformly coat the coating source material of the coating 114 around the body portion 113 according to a certain composition ratio and thickness. The main function of the coating 114 is to ensure the connecting component 11 is weldable and to firmly weld the connecting component 11 to the grid structure 101 of the battery cell 10, thus providing good current conduction.

[0049] In some embodiments, the body portion 113 is made of a conductive material with good conductivity, such as copper, nickel, gold, or silver, or an alloy material with low resistivity. When the resistivity of the body portion 113 is less than 1×10⁻⁶... -7 Ω·m, or conductivity greater than or equal to 1×10 7 At a resistance of S / m, the electrical loss of the body portion 113 is relatively small, resulting in higher battery efficiency and power generation. Resistivity is a physical quantity used to represent the electrical resistance of various materials, reflecting the property of a material to impede the flow of electric current. Conductivity is a parameter used to describe the ease with which charge flows through a material. In some embodiments, the body portion 113 is made of a copper layer, which has a low resistivity (1.75 × 10⁻⁶). -8 Copper has a lower cost than gold and silver (Ω·m). Furthermore, copper has high chemical stability and moderate strength, preventing deformation during soldering and lamination processes, thus minimizing the obstruction area of ​​the connecting component 11.

[0050] In some embodiments, the coating 114 is made of a metal or alloy with a lower melting point than the body 113, such as a tin alloy. Tin alloys may include tin-zinc alloys, tin-bismuth alloys, or tin-indium alloys. Tin is used as a welding material because of its low melting point and good affinity with metals such as copper, resulting in good weld strength. Lead in tin-lead alloys can lower the melting point of the solder strip, and tin and lead can form a eutectic point with a melting point of 183°C, exhibiting good welding and performance characteristics. Embodiments disclosed in this application use other metal elements to replace lead or add other elements, such as bismuth, to the tin-lead alloy. The use of bismuth can lower the melting point temperature and reduce surface tension. The melting point of the tin-bismuth alloy can be reduced to 139°C, meeting the requirements for low-temperature welding.

[0051] In some embodiments, coating 114 contains flux, which refers to a chemical substance that helps and promotes the welding process while providing protection and preventing oxidation. Flux includes inorganic flux, organic flux, and resin flux. It is understood that the flux has a lower melting point than coating 114 and increases the fluidity of the molten coating 114 to allow for good alloying between coating 114 and the grid structure 101.

[0052] In some embodiments, the cross-sectional shape of the connecting component 11 along the first direction Y is circular. Circular solder strips do not have orientation or alignment problems and are easier to mass-produce. In some embodiments, the cross-sectional shape of the connecting component 11 can be triangular or any other arbitrary shape to increase the contact area between the solder strip and the gate structure and reduce the alignment misalignment problem between the connecting component 11 and the gate structure.

[0053] In some embodiments, the surface of the connecting member 11 away from the battery casing has a reflective layer, which is located on the outer side of the coating 114 away from the battery. The reflective layer is used to reduce the shading area of ​​the connecting member 11 on the battery cell 10. In some embodiments, the outer surface of the coating 114 has reflective grooves, which are recessed grooves or channels extending from the coating 114 toward the body portion 113. Sunlight is reflected onto the battery cell 10 through the sidewalls of the reflective grooves, thereby improving the utilization rate of sunlight.

[0054] In some embodiments, the separator 12 serves two purposes: firstly, as a fixing film layer for the connecting component 11, it prevents the connecting component 11 from being pushed or deviated during the manufacturing process before alloying, thereby preventing situations such as poor soldering or missing soldering between the battery cell 10 and the connecting component 11; secondly, as a separator film layer for the connecting component 11, it prevents the molten adhesive film from flowing between the battery cell 10 and the connecting component 11 during the lamination process, and further flowing between the grid structure 101 and the connecting component 11, affecting the alloying of the grid structure 101 and the connecting component 11, and even affecting battery efficiency and power generation.

[0055] In some embodiments, the isolation layer 12 is an isolation adhesive layer. The isolation adhesive layer may include isolation tape or isolation adhesive. Isolation tape refers to a new material formed by coating an adhesive onto a substrate, while isolation adhesive refers to an adhesive. Therefore, isolation tape and isolation adhesive are not the same. When the isolation layer 12 is isolation tape, the isolation tape has two different film layers: the adhesive is used to fix the connecting component 11, and the substrate serves as the isolation film layer. Firstly, it prevents the molten adhesive film from flowing between the connecting component 11 and the grid structure 101 during the lamination process; secondly, it can serve as part of the encapsulation layer 13, reducing the probability of the connecting component 11 puncturing the encapsulation layer 13 during subsequent lamination processes, thus improving the yield of the photovoltaic module; and thirdly, it serves as an isolation film layer to isolate external moisture, protecting the solar cells from the danger of moisture corrosion, further improving the yield of the photovoltaic module.

[0056] In some embodiments, when the isolation layer 12 is an isolation adhesive, the adhesive has strong fluidity and adhesion, which can expel as much air as possible between the grid structure 101, the connecting component 11, and the isolation layer 12. This prevents subsequent issues such as poor mechanical strength due to gaps within individual solar photovoltaic cells, easy breakage, and gradual oxidation and corrosion of the grid structure 101 by moisture and corrosive gases in the air, thus affecting the performance of the grid structure 101. The properties of the isolation adhesive itself are beneficial to improving the yield of photovoltaic modules.

[0057] In some embodiments, the material of the isolation layer 12 is the same as the material of the encapsulation layer 13. (See reference...) Figure 7 The separator 12 is bonded to the adhesive film in the subsequent lamination process. As part of the encapsulation layer 13, the separator 12 does not suffer from incompatibility between film layers. The encapsulation layer 13 can better protect the solar cell 10 from moisture erosion and the risk of damage to the solar cell 10 due to internal voids.

[0058] In some embodiments, the separator 12 is a pre-crosslinked adhesive film with a crosslinking degree of 50% to 70%. The pre-crosslinked adhesive film refers to an adhesive film layer made of the same material as the subsequent encapsulation layer 13, which has been pre-treated with ultraviolet or infrared light to induce the small molecules within the film to combine and form macromolecules. With the pre-crosslinking degree within this range, the separator 12 can fix the connecting component 11 before lamination, preventing the connecting component 11 from moving. The separator 12 also prevents the solder ribbon from shifting due to the pushing of the molten adhesive film or the adhesive overflowing between the solder ribbon and the fine grid, which could cause the battery cell 10 to break or have poor soldering during the welding process between the connecting component 11 and the fine grid. Furthermore, if the degree of crosslinking is greater than 85%, the subsequent crosslinking reaction of the encapsulation layer 13 during lamination will increase adhesion, which will further crosslink the separator layer 12. As a result, the degree of crosslinking of the separator layer 12 is large and its hardness is large. This may lead to gaps between the separator layer 12, the battery cell 10 and the connecting component 11, or damage to the surface of the battery cell 10 caused by the hard separator layer 12, thus affecting the battery performance.

[0059] In some embodiments, along the first direction Y, the width of the insulating layer 12 satisfies both the requirement of being greater than the outer perimeter of the connecting member 11 and the requirement of discontinuity between adjacent insulating layers 12, or discontinuity between insulating layers 12 covering adjacent connecting members 11. This ensures that the insulating layer 12 covers the surface of the connecting member 11 and fulfills its function, namely, allowing the insulating film to flow between the grid structure 101 and the connecting member 11 and to isolate moisture. Furthermore, the discontinuity of adjacent insulating layers 12 serves two purposes: firstly, it reduces the amount of insulating layer 12 used, thus reducing costs; secondly, the spaced insulating layers 12 can maximize the removal of air between the battery cell 10 and the insulating layer 12.

[0060] In some embodiments, reference Figure 4 Along the first direction Y, the width L of the isolation layer 12 ranges from 0.8 to 5 mm. The width L of the isolation layer 12 can range from 0.8 to 4.8 mm, 0.8 to 4.2 mm, 1.0 to 4.8 mm, 1.0 to 3.7 mm, 0.8 to 2.6 mm, 0.8 to 2 mm, 0.9 to 4.9 mm, or 1.5 to 4.9 mm. Specifically, the width of the isolation layer 12 can be 0.8 mm, 1.95 mm, 2.21 mm, 3.39 mm, 3.82 mm, 4.18 mm, 4.39 mm, or 4.98 mm. With the width of the isolation layer 12 within the above range, the isolation layer 12 can both cover the surface of the connecting component 11 and ensure that adjacent isolation layers 12 are discontinuous.

[0061] In some embodiments, reference Figure 6The thickness E of the separator 12 ranges from 70 to 300 μm. Along the direction Z perpendicular to the surface of the solar cell 10, the thickness E of the separator 12 can range from 70 to 280 μm, 70 to 2000 μm, 70 to 150 μm, 70 to 110 μm, 100 to 300 μm, 100 to 230 μm, 150 to 300 μm, or 160 to 270 μm. Specifically, the thickness of the separator 12 can be 70 μm, 120 μm, 170 μm, 210 μm, 225 μm, 260 μm, or 290 μm. The thickness of the isolation layer 12 is within the above range, which can prevent the connecting component 11 from directly piercing the thickness of the isolation layer 12. At the same time, it can also make the side of the connecting component 11 away from the grid structure 101 after lamination not only have the isolation layer 12 but also have a certain thickness of encapsulation layer 13. The encapsulation layer 13 itself has adhesive properties, which can make the cover plate 14 more tightly combined with the connecting component 11 and the battery cell 10, thus playing a good encapsulation function.

[0062] In some embodiments, reference Figure 7 Along the first direction Y, one end of the separator 12 is located on the surface of the battery cell 10. The separator 12 can prevent the connecting component 11 from being pushed or deflected during the manufacturing process before alloying, thereby preventing the battery cell 10 and the connecting component 11 from having poor soldering or missing soldering. Being located on one side can also prevent the molten adhesive film of the connecting component 11 from flowing between the battery cell 10 and the connecting component 11 during the lamination process, and then flowing between the grid structure 101 and the connecting component 11, affecting the alloying of the grid structure 101 and the connecting component 11, and even affecting the battery efficiency and power generation.

[0063] In some embodiments, reference Figure 2 Along the first direction Y, the ends of both sides of the insulating layer 12 are located on the surface of the battery cell 10. Since both sides of the insulating layer 12 are located on the surface of the battery cell 10, the insulating layer 12 completely covers the surface of the battery cell 10, thereby preventing the encapsulation layer 13 from insulating the battery cell 10 and the connecting component 11 in all directions, and allowing the connecting component 11 to be fixed between the battery cells 10 without shifting during the manufacturing process.

[0064] In some embodiments, if the width of the isolation layer 12 is greater than or equal to the perimeter of the outer side of the connecting member 11 along the first direction, it can ensure that the isolation layer 12 isolates the battery cell 10 from the encapsulation layer 13 on at least one side, thereby ensuring that the isolation layer 12 covers the surface of the connecting member 11 and plays the role of the isolation layer 12, that is, the isolation film flows to the grid structure 101 and between the connecting member 11 and isolates moisture.

[0065] In some embodiments, along the arrangement direction X of the battery cells 10, the length of the separator 12 is greater than or equal to the length of the connecting member 11. Since the encapsulation layer 13 covers the surface of all battery cells 10, it is known that the encapsulation layer 13 also covers the battery gaps. The connecting member 11 is also located in the battery gaps to connect adjacent battery cells 10 in series or in parallel. When the length of the separator 12 is greater than or equal to the length of the connecting member 11, the molten adhesive film will not penetrate into the grid structure 101 and the connecting member 11 through the battery gaps or the edges of the battery cells 10, thereby improving the battery yield.

[0066] In some embodiments, the insulating layer 12 located in the battery gap can cover the surface of the connecting member 11 to ensure all-around alloying of the grid structure 101 and the connecting member 11. In some embodiments, the side of the insulating layer 12 away from the connecting member 11 has a reflective layer or reflective groove to improve the utilization rate of incident light.

[0067] In some embodiments, the encapsulation layer 13 includes a first encapsulation layer and a second encapsulation layer. The first encapsulation layer covers one of the front or back sides of the battery cell 10, and the second encapsulation layer covers the other of the front or back sides of the battery cell 10. Specifically, at least one of the first encapsulation layer or the second encapsulation layer may be an organic encapsulation film such as ethylene-vinyl acetate copolymer (EVA) film, polyvinyl octene coelastomer (POE) film, or polyvinyl butyral (PVB) film.

[0068] In some embodiments, the melting point of the encapsulation layer 13 is lower than the lamination temperature during the lamination process. The encapsulation layer 13 is a film layer composed of small molecules in the adhesive film that are in a molten state at the temperature of the laminator, and then the initiator in the encapsulation layer 13 causes the small molecules in the adhesive film to combine with each other to form cross-linked macromolecules.

[0069] In some embodiments, the melting points of the encapsulation layer 13 and the connecting member 11 can be set according to actual needs. When the melting point of the encapsulation layer 13 is greater than the melting point of the connecting member 11, the connecting member 11 can be alloyed before the encapsulation layer 13 reaches a molten state, which can effectively prevent the molten film from penetrating into the grid structure 101 and the connecting member 11 and from pushing the connecting member 11 to cause it to shift. When the melting point of the encapsulation layer 13 is less than the melting point of the connecting member 11, the lamination temperature can be set to be lower, thereby improving the thermal stress on the cell 10 and increasing the yield of the photovoltaic module.

[0070] In some embodiments, the melting point of the isolation layer 12 is greater than that of the encapsulation layer 13. When the encapsulation layer 13 is in a molten state, the isolation layer 12 still maintains a good morphology, thereby effectively preventing the molten adhesive film from penetrating into the grid structure 101 and the connecting member 11 and from pushing the connecting member 11 to cause it to shift.

[0071] In some embodiments, when the isolation layer 12 is a pre-crosslinked adhesive film, the increase in the degree of crosslinking makes the melting point of the isolation layer 12 greater than that of the encapsulation layer 13. Therefore, even if the material of the isolation layer 12 is the same as that of the encapsulation layer 13, the melting point of the isolation layer 12 will be greater than that of the encapsulation layer 13, thereby effectively preventing the molten adhesive film from immersing into the gate structure 101 and the connecting member 11 and from pushing the connecting member 11 to cause it to shift.

[0072] In some embodiments, the cover plate 14 can be a glass cover plate, a plastic cover plate, or other cover plate with light-transmitting function. Specifically, the surface of the cover plate 14 facing the encapsulation layer 13 can be an uneven surface, thereby increasing the utilization rate of incident light. The cover plate 14 includes a first cover plate and a second cover plate, the first cover plate being opposite to the first encapsulation layer, and the second cover plate being opposite to the second encapsulation layer.

[0073] In some embodiments, the thickness D of the encapsulation layer 13 satisfies the formula: D = (B + C) - E, where B is the bottom surface of the connecting member 11 in contact with the solar cell 10, and C is the distance between the top surface of the connecting member 11 and the side of the encapsulation layer 13 closest to the connecting member 11; E is the thickness of the isolation layer 12, and C is the distance between the top surface of the connecting member 11 and the cover plate 14. By reasonably setting the thickness of the isolation layer 12, it is equivalent to locally thickening the protective layer where the connecting member 11 is located, preventing the film thickness on the connecting member 11 from being insufficient to cover the connecting member 11 during subsequent lamination, causing the connecting member 11 to puncture the film, affecting the isolation performance of the film, and improving the yield of the photovoltaic module. Therefore, the thickness of the film in areas other than the connecting member 11 can be set smaller, that is, the thickness D of the encapsulation layer 13 is equal to the thickness of the conventional film minus the thickness of the isolation layer 12, reducing the overall weight of the film, thereby saving the cost of manufacturing the photovoltaic module. Figure 2In some embodiments, the thickness D of the encapsulation layer 13 is the thickness before lamination, the thickness E of the separator layer 12 is the thickness before lamination, the distance B between the bottom surface of the connecting member 11 in contact with the battery cell 10 and the top surface of the connecting member 11 near the encapsulation layer 13 is the distance before lamination, and the distance C between the top surface of the connecting member 11 and the cover plate 14 is the distance before lamination. It is understood that the above formulas are used to obtain the optimal thickness range of the encapsulation layer to achieve better power generation and manufacturing costs. The thickness D of the encapsulation layer is substantially equal to the formula. That is, there can be a relative error of ±20% between the thickness D of the encapsulation layer and (B+C)-E. In other words, D can meet the following formula: 0.8×[(B+C)-E]≤D≤1.2×[(B+C)-E].

[0074] In some embodiments, the distance C between the top surface of the connecting member 11 and the cover plate 14 is a fixed value, and the distance between the connecting member 11 and the cover plate 14 depends on the diameter of the connecting member 11 or the bottom surface of the connecting member 11 that contacts the battery cell 10, and the distance B of the top surface of the connecting member 11 near the encapsulation layer 13. That is, the larger B is, the larger C is. In some embodiments, C can be 1.2 to 4 times B.

[0075] In some embodiments, the distance B between the bottom surface of the connecting member 11 that contacts the battery cell 10 and the top surface of the connecting member 11 near the encapsulation layer 13 ranges from 80 to 200 μm. Specifically, B can be 80–150 μm, 80–100 μm, 80–130 μm, 100–200 μm, 120–150 μm, or 120–150 μm. B can specifically be 81 μm, 93 μm, 107 μm, 135 μm, 154 μm, 168 μm, or 300 μm. The thickness D of the encapsulation layer 13 can be 200–300 μm. D can range from 210–300 μm, 243–300 μm, 280–300 μm, 200–280 μm, 243–298 μm, or 220–300 μm. Specifically, D can be 201um, 232um, 245um, 254um, 273um, 283um, or 297um.

[0076] In some embodiments, reference Figure 8It also includes multiple connecting layers 105, which are spaced apart along the direction of extension of the connecting member 11 and located between the battery cell 10 and the connecting member 11. The connecting layer 105 is a positioning adhesive, which positions the connecting member 11 by applying adhesive dots, accurately positioning the positional relationship between the connecting member 11 and the grid structure 101, and ensuring good contact between the connecting member 11 and the battery in subsequent welding or lamination processes, thereby maximizing battery efficiency. In addition, the positioning adhesive makes the length of the grid structure 101 between adjacent connecting members 11 similar, resulting in a more uniform transmission path for the current collected by the battery cell 10 and reducing transmission loss.

[0077] In some embodiments, along the first direction Y, the width of the connecting layer 105 is greater than the width of the connecting member 11, and the connecting layer 105 surrounds a portion of the height of the connecting member 11. Thus, the thickness of the connecting layer 105 can firmly position the connecting member 11 onto the battery cell 10, preventing the connecting member 11 from shifting during subsequent operations. In some embodiments, the material of the connecting layer 105 is adhesive.

[0078] In some embodiments, the extending direction X of the battery cell 10 and the first direction Y can be perpendicular to each other, or they can have an angle of less than 90 degrees, such as 60 degrees, 45 degrees, 30 degrees, etc., as long as the extending direction X of the battery cell 10 and the first direction Y are not in the same direction. For ease of explanation and understanding, this embodiment uses the example of the extending direction X of the battery cell 10 being perpendicular to the first direction Y. In specific applications, the angle between the extending direction X of the battery cell 10 and the first direction Y can be adjusted according to actual needs and application scenarios; this embodiment does not impose any limitations on this.

[0079] In the photovoltaic module provided in this application embodiment, an isolation layer 12 is formed on the surface of the connecting component 11. The isolation layer 12 covers the surface of the connecting component 11, preventing the encapsulation layer 13 from flowing between the connecting component 11 and the cell 10 during the lamination process, and even preventing electrical insulation. The connecting component 11 is connected to two cells 10, and each isolation layer 12 covers each connecting component 11. This prevents the material of the encapsulation layer 13 from entering between the grid structure 101 and the connecting component 11 through the edge of the cell 10, further ensuring the safety of the assembly of the cell 10 and the connecting component 11. In addition, by reasonably setting the thickness of the isolation layer 12, it is equivalent to locally thickening the protective layer position where the connecting component 11 is located. This prevents the film thickness on the connecting component 11 from being insufficient to cover the connecting component 11 during subsequent lamination processes, causing the connecting component 11 to puncture the film and affect the isolation performance of the film, thereby improving the yield of the photovoltaic module. Therefore, the thickness of the encapsulant film in areas other than the non-connecting component 11 can be set to be smaller, that is, the thickness D of the encapsulation layer 13 is equal to the thickness of the conventional encapsulant film minus the thickness of the isolation layer 12, which reduces the overall weight of the encapsulant film and thus saves the cost of manufacturing photovoltaic modules.

[0080] Accordingly, another aspect of this application provides a method for preparing a photovoltaic module, which is used to prepare the photovoltaic module provided in the above embodiments. The same or similar components as those in the above embodiments will not be described in detail here.

[0081] refer to Figure 2 A battery cell 10 is provided, the surface of which has a grid line structure 101 extending along a first direction Y.

[0082] In some embodiments, a series of interconnecting layers 105 are provided on the surface of the battery cell 10 at intervals. The interconnecting layers 105 are located between adjacent grid line structures 101. The interconnecting layers 105 can be arranged at intervals along the battery cell arrangement direction X; or they can be arranged in a staggered manner along the battery cell arrangement direction X. That is, the first interconnecting layer 105 is located between the first grid line structure 101 and the second grid line structure 101, the second interconnecting layer 105 is located between the second grid line structure 101 and the third grid line structure 101, the third interconnecting layer 105 is located between the first grid line structure 101 and the second grid line structure 101, and so on.

[0083] In some embodiments, the connection layer 105 may be omitted.

[0084] In some embodiments, a layer such as... is laid on the surface of the battery cell 10. Figure 1The connecting component 11 shown has an insulating layer 12 covering its surface. The length of the insulating layer 12 along the second direction X is greater than 2 / 3 of the outer perimeter of the coating 114, to form a relatively complete encapsulation. Furthermore, the length of the insulating layer 12 is greater than the outer perimeter of the coating 114, and both ends of the insulating layer 12 are located on the surface of the battery cell 10. It is understood that due to the insulating layer 12's certain toughness and the effect of gravity, a certain amount of porosity is formed between the insulating layer 12, the battery cell 10, and the connecting component 11, i.e., reference... Figure 10 If part of the coating 114 is not completely covered by the insulating layer 12, the uncovered coating 114 will be transformed into the first part 111 in subsequent lamination, and the coating 114 covered by the insulating layer 12 will be transformed into the second part 112. Due to the temperature transfer and the sealing of the insulating layer 12, the thickness of the second part 112 increases as it moves further away from the surface of the battery cell 10. The second part 112 can act as a partial thickness barrier layer to prevent the main body 113 from piercing the encapsulation layer 13; the encapsulation layer 13 other than the connecting member 11 can be made thinner, achieving the effect of a low-weight adhesive film and reducing costs. In addition, since the second part 112 does not melt, the shading area of ​​the connecting member 11 on the battery cell 10 will be reduced accordingly. On the one hand, the thickness of the second part 112 can be made thinner than the thickness of the first part 111 in the initial stage of setting the connecting member 11, reducing costs; on the other hand, the smaller shading area caused by the connecting member 11 reduces the optical loss of the battery cell 10 and is beneficial to improving battery efficiency.

[0085] In some embodiments, the first part 111 and the second part 112 are discontinuous; that is, during the welding process, part of the coating 114 melts to form the first part 111, and part of the coating 114 is retained due to the action of the insulating layer 12 to form the second part 112, and the first part 111 and the second part 112 are disconnected. In some embodiments, the first part 111 and the second part 112 are continuous film layers, with the coating 114 in a defined portion area and the coating 114 on the surface of the battery cell 10 constituting the first part 111, and the remaining coating 114 constituting the second part 112.

[0086] In some embodiments, if the proportion of the second part 112 is greater than that of the first part 111, then compared to a situation where the proportion of the second part 112 is less than or equal to that of the first part 111, the shading area formed by the alloying of the connecting component 11 and the grid structure is smaller, resulting in lower electrical losses in the photovoltaic module. If the proportion of the unmelted second part 112 is greater than that of the melted first part 111, the lamination temperature can be set lower, avoiding problems such as thermal warping of the solar cell 10 caused by higher temperatures.

[0087] In some embodiments, in a cross-sectional view perpendicular to the extending direction of the connecting member 11, the proportion of the first part 111 is 1 / 4 to 2 / 3 times that of the second part 112. Regarding the proportion range of the first part 111 and the second part 112, when the first part 111 is larger, the contact surface between the connecting member 11 and the grid structure is larger, resulting in a larger contact area, lower contact resistance, and a wider current collection range for the connecting member 11, which is beneficial for improving power generation. When the first part 111 is smaller, the shading area of ​​the connecting member 11 is smaller, electrical losses are lower, and the lamination temperature is lower, thus reducing the degree of thermal stress on the solar cell 10, which is beneficial for improving the yield of the photovoltaic module.

[0088] In some embodiments, the region having the connecting layer 105 is subjected to ultraviolet (UV) fixation to enhance the adhesion of the connecting layer 104. (Reference) Figure 12 Since the connecting layer 104 encapsulates the coating 114, the portion of the coating 114 located within the connecting layer 104 constitutes the third part 116. For the same connecting component 11, the proportion of the third part 116 is smaller than that of the first part 111. A larger proportion of the third part 116 indicates a thicker connecting layer 104, ensuring that the connecting component 11 will not shift during operations prior to lamination. Conversely, a smaller proportion of the third part 116 indicates a smaller proportion of the first part 111, resulting in a smaller diffusion and shielding area for the connecting component 11 and reduced electrical losses.

[0089] In some embodiments, an adhesive film is provided, which is laid on the surface of the battery cell 10 and covers the surfaces of the battery cell 10, the connecting member 11, and the insulating layer 12; a cover plate 14 is provided on the surface of the adhesive film away from the battery cell 10; a lamination process is performed, and the coating 114 is transformed into a first part and a second part, or a first part, a second part, and a third part. (See reference) Figure 10 When the material of the separator 12 and the adhesive film is the same, that is, when the separator 12 is a pre-crosslinked adhesive film, the adhesive film and the separator 12 are bonded together to form the encapsulation layer 13. (Reference) Figure 11 When the material of the isolation layer 12 is different from that of the adhesive film, the adhesive film is transformed into the encapsulation layer 13, while the isolation layer 12 is still retained.

[0090] Example 0: Without the isolation layer 12, the connecting components and grid structure are alloyed before the encapsulation layer 13 is laid. Alloying is typically achieved through welding. Then, the encapsulation layer and cover plate are laid, followed by lamination. The thickness D of the encapsulation layer 13 is 420 μm. After lamination, the distance B between the bottom surface of the connecting component 11 in contact with the battery cell 10 and the top surface of the connecting component 11 near the encapsulation layer 13 is 200 μm, and the distance C between the top surface of the connecting component 11 and the cover plate 14 is 400 μm.

[0091] Example 1: The thickness E of the separator 12 is 70 μm. The thickness D of the encapsulation layer 13 is 230 μm. The lamination process alloys the connecting component 11 and the grid structure. The distance B between the bottom surface of the connecting component 11 in contact with the cell 10 and the top surface of the connecting component 11 near the encapsulation layer 13 is 80 μm, and the distance C between the top surface of the connecting component 11 and the cover plate 14 is 300 μm.

[0092] Example 2: The thickness E of the separator 12 is 210 μm. The thickness D of the encapsulation layer 13 is 200 μm. The lamination process alloys the connecting component 11 and the grid structure. The distance B between the bottom surface of the connecting component 11 in contact with the cell 10 and the top surface of the connecting component 11 near the encapsulation layer 13 is 200 μm, and the distance C between the top surface of the connecting component 11 and the cover plate 14 is 400 μm.

[0093] Example 3: The thickness E of the isolation layer 12 is 150 μm. The thickness D of the encapsulation layer 13 is 250 μm. The lamination process alloys the connecting component 11 and the grid structure. The distance B between the bottom surface of the connecting component 11 in contact with the cell 10 and the top surface of the connecting component 11 near the encapsulation layer 13 is 200 μm, and the distance C between the top surface of the connecting component 11 and the cover plate 14 is 400 μm.

[0094] Example 4: The thickness E of the separator 12 is 150 μm. The thickness D of the encapsulation layer 13 is 150 μm. The lamination process alloys the connecting component 11 and the grid structure. The distance B between the bottom surface of the connecting component 11 in contact with the cell 10 and the top surface of the connecting component 11 near the encapsulation layer 13 is 80 μm, and the distance C between the top surface of the connecting component 11 and the cover plate 14 is 300 μm.

[0095] Comparative Example 1: The thickness E of the separator 12 is 0. The thickness D of the encapsulation layer 13 is 200 μm. The lamination process alloys the connecting component 11 and the grid structure. The distance B between the bottom surface of the connecting component 11 in contact with the cell 10 and the top surface of the connecting component 11 near the encapsulation layer 13 is 80 μm, and the distance C between the top surface of the connecting component 11 and the cover plate 14 is 180 μm.

[0096] Comparative Example 2: The thickness E of the separator 12 is 0. The thickness D of the encapsulation layer 13 is 420 μm. The lamination process alloys the connecting component 11 and the grid structure. The distance B between the bottom surface of the connecting component 11 in contact with the cell 10 and the top surface of the connecting component 11 near the encapsulation layer 13 is 200 μm, and the distance C between the top surface of the connecting component 11 and the cover plate 14 is 400 μm.

[0097] Comparative Example 3: The thickness E of the separator 12 is 150 μm. The thickness D of the encapsulation layer 13 is 300 μm. The lamination process alloys the connecting component 11 and the grid structure. The distance B between the bottom surface of the connecting component 11 in contact with the cell 10 and the top surface of the connecting component 11 near the encapsulation layer 13 is 80 μm, and the distance C between the top surface of the connecting component 11 and the cover plate 14 is 300 μm.

[0098] Table 1

[0099]

[0100] As shown in Table 1, increasing the thickness of the isolation layer can reduce costs, decrease the probability of the connecting component piercing the encapsulation layer, and improve the welding effect between the connecting component and the gate wire structure. Specifically, the ratio of welding pull force in each embodiment, Comparative Examples 1 and 2, and Example 0 demonstrates that the isolation layer can effectively prevent the encapsulation layer from seeping into the space between the gate wire structure and the connecting component during the alloying process of lamination, thereby improving the yield of electrical connection between the connecting component and the gate wire structure.

[0101] By comparing the various embodiments and Comparative Example 3, it is found that the thickness of the isolation layer and the encapsulation layer is much greater than the distance C between the top surface of the connecting component 11 and the cover plate 14, which increases the manufacturing cost without significantly improving the prevention of puncture or the yield of electrical connections. Furthermore, compared with Embodiment 4, Comparative Example 3 increased the thickness of the encapsulation layer, but all performance characteristics decreased. This demonstrates that the isolation layer in this application has a significant impact on both cost and battery yield.

[0102] While this application discloses preferred embodiments as described above, it is not intended to limit the scope of the claims. Any person skilled in the art can make various possible variations and modifications without departing from the concept of this application. Therefore, the scope of protection of this application should be determined by the scope defined in the claims. Furthermore, the embodiments and accompanying drawings in this specification are merely illustrative and do not represent the full scope of protection of the claims.

[0103] Those skilled in the art will understand that the above embodiments are specific examples of implementing this application, and in practical applications, various changes can be made in form and detail without departing from the spirit and scope of this application. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of this application; therefore, the scope of protection of this application should be determined by the scope defined in the claims.

Claims

1. A photovoltaic module, characterized by, include: At least two battery cells; Multiple connecting components are arranged at intervals along a first direction, the connecting components being used to connect adjacent battery cells; Multiple insulating layers are spaced apart along the first direction, each insulating layer covers each of the connecting components, and at least a portion of the insulating layers are also located on the surface of the battery cell along the first direction; An encapsulation layer that covers the surface of the insulating layer and the surface of the battery cell; A cover plate, the cover plate being located on the side of the encapsulation layer away from the battery cell; The thickness D of the encapsulation layer satisfies the formula: D=(B+C)-E, where B is the bottom surface of the connecting component that contacts the battery cell, and E is the distance between the top surface of the connecting component and the side of the encapsulation layer; E is the thickness of the isolation layer, and C is the distance between the top surface of the connecting component and the cover plate. Wherein, the thickness D of the encapsulation layer is the thickness before lamination; B is the distance between the bottom surface of the connecting component and the battery cell before lamination, and the distance between the top surface of the connecting component and the side of the encapsulation layer; and E is the thickness of the isolation layer before lamination.

2. The photovoltaic module of claim 1, wherein, Along the first direction, the ends of both sides of the insulating layer are located on the surface of the battery cell.

3. The photovoltaic module according to claim 1 or 2, characterized in that Along the first direction, the width of the isolation layer is greater than or equal to the perimeter of the outer side of the connecting component.

4. The photovoltaic module of claim 1, wherein, Along the arrangement direction of the battery cells, the length of the insulating layer is greater than or equal to the length of the connecting component.

5. The photovoltaic module according to claim 1, characterized in that, The melting point of the isolation layer is greater than that of the encapsulation layer.

6. The photovoltaic module of claim 1 or 5, wherein, The isolation layer is a pre-crosslinked adhesive film, and the degree of crosslinking of the pre-crosslinked adhesive film is 50%~70%.

7. The photovoltaic module of claim 6, wherein, The material of the isolation layer is the same as the material of the encapsulation layer.

8. The photovoltaic module of claim 1, wherein, The isolation layer is an isolation adhesive layer.

9. The photovoltaic module of claim 1, wherein, Also includes: Multiple connecting layers are arranged at intervals along the direction of extension of the connecting component, and the connecting layers are located between the battery cell and the connecting component.

10. The photovoltaic module according to claim 9, characterized in that, Along the first direction, the width of the connecting layer is greater than the width of the connecting member, and the connecting layer surrounds the connecting member at a certain height.

11. The photovoltaic module of claim 1, wherein, Along the first direction, the width of the isolation layer ranges from 0.8 to 5 mm; the thickness of the isolation layer ranges from 70 to 300 μm.

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