Photovoltaic module

Abstract

The embodiment of the invention relates to the photovoltaic field, and provides a photovoltaic module, and the photovoltaic module comprises a battery piece which comprises a welding region and a collection region which are arranged in a first direction; the surface of the battery piece is provided with a plurality of grid lines arranged in the second direction, each grid line comprises at least two welding grid lines located in the welding area and a collection grid line located in the collection area, the welding grid lines are arranged in the second direction, and each welding grid line in the at least two welding grid lines is electrically connected with the same collection grid line; the connecting part is located on the battery piece, the connecting part is electrically connected with the multiple grid lines arranged in the second direction, and the connecting part is connected with each welding grid line in a welding mode. The photovoltaic module provided by the embodiment of the invention at least can reduce the power generation loss.

Description

Technical Field

[0001] The embodiments of the present application relate to the photovoltaic field, and in particular to a photovoltaic module. Background Art

[0002] Solar cells are devices that directly convert light energy into electrical energy through the photoelectric effect or photochemical effect. Single solar cells cannot be used to generate electricity directly. Several single cells must be connected in series and parallel through welding strips and tightly sealed into components before use. Solar cell components (also called solar panels) are the core part of solar power generation systems and the most important part of solar power generation systems. The function of solar cell components is to convert solar energy into electrical energy, or send it to batteries for storage, or drive loads to work.

[0003] The main grid and fine grid on the solar cell are key components to ensure the efficiency of solar energy conversion. The main grid line is responsible for collecting solar energy, while the fine grid line increases the light absorption and current transmission effect. The two work together to ensure the maximum absorption and conversion efficiency of solar energy. The main grid line is directly connected to the external lead of the battery (i.e. the connecting component) and is a relatively thick part. The fine grid line plays the role of collecting and transmitting current to the main line. It is a relatively thin part and is made into a narrow and thin grid line to overcome the resistance of the diffusion layer.

[0004] However, the front grid lines (main grid lines and thin grid lines) will block part of the silicon wafer, so the light energy on the grid lines cannot be converted into electrical energy, resulting in waste. In addition, the main component of the slurry for making the grid lines is the relatively expensive precious metal silver, so there is also a cost issue. Based on this, technicians have made more and thinner connecting components directly connect the battery grids, collect current and realize battery interconnection at the same time, and cancel the traditional main grid at the battery level, that is, "busbar-free" technology. However, there are still many factors that affect the yield rate and power generation loss of photovoltaic modules, such as the welding effect between the connecting components and the thin grids and the welding yield rate. Summary of the invention

[0005] The embodiments of the present application provide a photovoltaic module that at least helps to reduce power generation losses.

[0006] According to some embodiments of the present application, the embodiments of the present application provide a photovoltaic component, including: a battery cell, the battery cell including a welding area and a collecting area arranged along a first direction; a surface of the battery cell having a plurality of grid lines arranged along a second direction, each grid line including at least two welding grid lines located in the welding area and a collecting grid line located in the collecting area, wherein the welding grid lines are arranged along the second direction, and each of the at least two welding grid lines is electrically connected to the same collecting grid line; a connecting component, the connecting component is located on the battery cell, the connecting component is electrically connected to the plurality of grid lines arranged along the second direction, and the connecting component is welded and connected to each welding grid line.

[0007] In some embodiments, a width of the welding grid line along the second direction is greater than or equal to a width of the collecting grid line along the second direction.

[0008] In some embodiments, the welding grid lines include first-type grid lines and second-type grid lines, the first-type grid lines and the collecting grid lines are formed of a burn-through paste, and the second-type grid lines are formed of a non-burn-through paste.

[0009] In some embodiments, the welded grid lines include: a first sub-grid line and a second sub-grid line stacked together, the second sub-grid line is located between the connecting component and the first sub-grid line, and the first sub-grid line and the second sub-grid line are made of different materials.

[0010] In some embodiments, the battery cell is a back-contact battery cell, the gate lines include a first gate line of a first conductive type and a second gate line of a second conductive type, the first gate lines include a first welding gate line corresponding to the first welding area and a first collecting gate line corresponding to the first collecting area, the second gate lines include a second welding gate line corresponding to the second welding area and a second collecting gate line corresponding to the second collecting area, the first welding area is opposite to the second collecting area along the second direction, and the second welding area is opposite to the first collecting area along the second direction; and also includes: an insulating layer, the insulating layer is located between the connecting component and the second collecting gate line.

[0011] In some embodiments, the insulating layer is located on the first gate line and the second gate line, and the region of the insulating layer corresponding to the first welding region exposes the first welding gate line.

[0012] In some embodiments, at least two first welding gate lines of the same first gate line contact each other to form a pad, and a width of the pad along the second direction is greater than a width of the first collecting gate line along the second direction.

[0013] In some embodiments, corresponding to the area of ​​the connection component, the top surface of the first welding wire close to the insulation layer is higher than the top surface of the first welding wire far from the insulation layer.

[0014] In some embodiments, the spacing between the insulating layer and the first welding grid is proportional to the thickness of the insulating layer.

[0015] In some embodiments, the thickness of the insulating layer decreases along the second direction and toward the first welding grid line.

[0016] In some embodiments, the second collecting gate line includes two broken gates and a break located between the two broken gates, the break corresponds to the first welding area, and the broken gates are located on both sides of the connecting component and are insulated from the connecting component.

[0017] The technical solution provided by the embodiments of the present application has at least the following advantages:

[0018] The photovoltaic module provided by the embodiment of the present application comprises a plurality of grid lines and connecting components arranged along the second direction on the surface of the cell, the connecting components are welded and connected to each welding grid line, and the number of welding grid lines is large, that is, the number of welding points between the cell and the connecting components is large, so that the welding tension between the cell and the connecting components can be increased, and the problem of the connecting components detaching from the cell can be avoided, as well as the problem of poor EL appearance and power generation loss caused by cold welding can be avoided. A collecting grid line is electrically connected to a plurality of welding grid lines, so that the grid lines on the cell can be connected to the connecting components through multiple paths, effectively avoiding the situation of power generation loss caused by the broken grid problem. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] One or more embodiments are exemplarily illustrated by the figures in the corresponding drawings. These exemplified descriptions do not constitute a limitation on the embodiments. Unless otherwise specified, the figures in the drawings do not constitute a scale limitation. In order to more clearly illustrate the embodiments of the present application or the technical solutions in the traditional technology, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 A schematic diagram of the structure of a photovoltaic module provided in one embodiment of the present application;

[0021] Figure 2 A top view of a photovoltaic module provided in one embodiment of the present application;

[0022] Figure 3 for Figure 2 A partial cross-sectional view of

[0023] Figure 4 Four schematic diagrams of welding grid lines in a photovoltaic module provided in an embodiment of the present application;

[0024] Figure 5 A top view of a welded grid line in a photovoltaic module provided in one embodiment of the present application;

[0025] Figure 6 A partial cross-sectional view of a photovoltaic module provided in one embodiment of the present application;

[0026] Figure 7 Another top view of a welded grid line in a photovoltaic module provided by an embodiment of the present application;

[0027] Figure 8 for Figure 7 a corresponding cross-sectional view;

[0028] Fig. 9 A schematic structural diagram of a photovoltaic module provided in another embodiment of the present application;

[0029] Fig.10 A top view of a photovoltaic assembly provided by another embodiment of the present application;

[0030] Fig.11 Another top view of a photovoltaic module provided by another embodiment of the present application;

[0031] Fig.12 for Fig.11 A partial cross-sectional view of

[0032] Fig.13 for Fig.11 Another partial cross-sectional view of

[0033] Fig.14 A partial top view of a photovoltaic assembly provided in another embodiment of the present application. DETAILED DESCRIPTION

[0034] As can be seen from the background technology, the power generation loss of current photovoltaic modules is relatively large.

[0035] Analysis found that one of the reasons for the current power generation loss is that the mainstream silver electrode is a combination of silver and glass, with a loose structure and insufficient stability. In addition, it has a different melting point from the copper welding tape. If 0BB technology is used, the single-point welding area is reduced by 90%. When subjected to external force or thermal expansion and contraction, the welding tape and the battery cell are easily separated, causing power generation loss.

[0036] An embodiment of the present application provides a photovoltaic module, which increases the welding area between the connecting component and the battery cell by setting a welding grid line, and the multiple welding grid lines are welded to the connecting component, which is beneficial to improving the welding tension, thereby avoiding the connection component from being cold-soldered and the connection component from being detached from the battery cell, etc., which is beneficial to improving the yield rate of the photovoltaic module and the battery efficiency of the photovoltaic module.

[0037] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0038] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0039] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists, A and B exist at the same time, and B exists. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0040] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0041] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the embodiments of the present application.

[0042] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0043] In the accompanying drawings corresponding to the embodiments of the present application, the thickness and area of ​​the layer are magnified for better understanding and ease of description. When describing a component (such as a layer, film, region or substrate) on another component or on the surface of another component, the component can be "directly" located on the surface of another component, or there can be a third component between the two components. On the contrary, when describing a component on the surface of another component or when another component is formed or provided on the surface of a component, it means that there is no third component between the two components. In addition, when describing a component as "substantially" formed on another component, it means that the component is not formed on the entire surface (or front surface) of the other component, nor is it formed on a partial edge of the entire surface.

[0044] In the description of the embodiments of the present application, when a component "includes" another component, unless otherwise specified, other components are not excluded, and other components may be further included. In addition, when a component such as a layer, film, region, or plate is referred to as being "on / located on" another component, it may be "directly on" the other component (i.e., located on the surface of the other component with no other components between them), or another component may exist in between. In addition, when a component such as a layer, film, region, or plate is "directly located on" another component, or when a component such as a layer, film, region, or plate is located on the surface of another component, it means that no other components are located in between.

[0045] The terms used in the description of the various embodiments described herein are only used to describe specific embodiments and are not intended to be limiting. As used in the description of the various embodiments described and in the appended claims, "the part" is also intended to include the plural form unless the context clearly indicates otherwise. Among them, a component includes a layer, a film, a region, or a plate.

[0046] The following will describe the various embodiments of the present application in detail with reference to the accompanying drawings. However, it will be appreciated by those skilled in the art that in the various embodiments of the present application, many technical details are provided in order to enable the reader to better understand the present application. However, even without these technical details and various changes and modifications based on the following embodiments, the technical solution claimed in the present application can be implemented.

[0047] Figure 1 A schematic diagram of the structure of a photovoltaic module provided in one embodiment of the present application; Figure 2 A top view of a photovoltaic module provided in one embodiment of the present application; Figure 3 for Figure 2 A partial cross-sectional view of. Figure 2 The connecting component in the apparatus is in a semi-transparent state, and the adhesive film and the cover plate are in a transparent state, that is, the welding grid lines under the connecting component can be seen through the connecting component. Figure 3The cross-sectional view in FIG. 1 does not show the adhesive film and the cover plate, but in reality, there is an adhesive film in the gap between the two welding grid lines.

[0048] The present application embodiment provides a photovoltaic module for reducing power generation losses. Figure 1 and Figure 2 The photovoltaic module includes: a cell 100, the cell 100 includes a welding area 101 and a collecting area 102 arranged along a first direction X. The surface of the cell 100 has a plurality of grid lines 110 arranged along a second direction Y, each grid line 110 includes at least two welding grid lines 111 located in the welding area 101 and a collecting grid line 112 located in the collecting area 102, wherein the welding grid lines 111 are arranged along the second direction Y, and each of the at least two welding grid lines 111 is electrically connected to the same collecting grid line 112. The photovoltaic module includes: a connecting component 120, the connecting component 120 is located on the cell 100, the connecting component 120 is electrically connected to the plurality of grid lines 110 arranged along the second direction Y, and the connecting component 120 is welded and connected to each welding grid line 111.

[0049] In the photovoltaic module provided by the embodiment of the present application, the surface of the cell 100 includes a plurality of grid lines 110 and a connecting component 120 arranged along the second direction Y, and the connecting component 120 is welded and connected to each welding grid line 111. The number of welding grid lines 111 is large, that is, the number of welding points between the cell 100 and the connecting component 120 is large, so that the welding tension between the cell 100 and the connecting component 120 can be increased, and the problem of the connecting component 120 being separated from the cell 100 can be avoided, and the problem of poor EL appearance and power generation loss caused by cold welding can be avoided. A collecting grid line 112 is electrically connected to a plurality of welding grid lines 111, so that the grid lines on the cell can be connected to the connecting component 120 through multiple paths, effectively avoiding the situation of power generation loss caused by the broken grid problem.

[0050] In some embodiments, the cell 100 may include but is not limited to any one of a PERC cell (Passivated Emitter Rear Cell), a PERT cell (Passivated Emitter and Rear Totally-diffused cell), a TOPCon cell (Tunnel Oxide Passivated Contact), and a HIT / HJT cell (Heterojunction Technology).

[0051] In some embodiments, the cell 100 can be a monocrystalline silicon solar cell, a polycrystalline silicon solar cell, an amorphous silicon solar cell or a multi-compound solar cell. The multi-compound solar cell can specifically be a cadmium sulfide solar cell, a gallium arsenide solar cell, a copper indium selenide solar cell or a perovskite solar cell.

[0052] In some embodiments, the battery cell 100 is a whole cell or a sliced ​​cell. A sliced ​​cell refers to a cell formed by a complete whole cell through a cutting process. The cutting process includes: a laser slotting + cutting (Linear Spectral Clustering, LSC) process and a thermal stress cell separation (TMC) process.

[0053] In some embodiments, the sliced ​​battery is a half-cell battery, and the half-cell battery can also be understood as a half-cell battery or a two-slice battery. The function of the half-cell assembly is to increase the power generation power by reducing the resistance loss. The half-cell assembly can optimize the width of the connecting component 120 in the battery. Conventionally, it is necessary to increase the width of the connecting component 120 to reduce the power generation loss and reduce the width of the connecting component 120 to reduce the shading loss. An optimized balance is made. The half-cell assembly reduces the battery loss, and the width of the connecting component 120 can be set thinner to reduce the shading loss, which is beneficial to improve the battery efficiency and power consumption of power generation. In other embodiments, the sliced ​​battery can be a three-slice battery, a four-slice battery, or an eight-slice battery.

[0054] The welding area 101 refers to the area where the connection component 120 is welded to the battery cell. In order to make the area contacted by the connection component 120 the welding area 101, the area of ​​the welding area 101 is generally set to be larger than the area of ​​the connection component 120. Figure 2 The width of the connecting member 120 is shown to be smaller than the width of the welding region 101 .

[0055] The collection area 102 refers to the area on the battery cell except the welding area 101, which is used to collect and aggregate current.

[0056] It should be noted that the welding grid lines 111 corresponding to the welding area 101 not only have the function of achieving alloy contact with the connecting component 120, but also have the function of collecting and summing the current.

[0057] The welding grid lines 111 are used to form alloy contact with the connection components 120, so as to achieve the purpose of welding. The alloy contact between the welding grid lines 111 and the connection components 120 can be formed by welding or lamination.

[0058] In some embodiments, the width of the welding gate line 111 is equal to the width of the collecting gate line 112. In this way, the shielding area of ​​the welding gate line 111 can be reduced, thereby improving the photoelectric conversion efficiency of the battery.

[0059] In other embodiments, the width of the welding grid line 111 is greater than the width of the collecting grid line 112. The width of the welding grid line 111 is set to be larger, and the contact area between the connecting component 120 and the welding grid line 111 is larger, so that the performance of the alloy contact between the connecting component 120 and the welding grid line 111 can be improved, thereby improving the welding quality, avoiding the problem of cold solder joints and the problem of power generation loss caused by the connection component 120 being separated from the battery cell. Secondly, the width of the welding grid line 111 is larger, and during the welding process, the probability of the welding grid line 111 being broken due to thermal expansion and contraction of the tin layer on the connecting component 120 also decreases, thereby improving the poor appearance of the EL and reducing power generation loss.

[0060] In some embodiments, the number of welding grid lines 111 may be 2 to 5. A larger number of welding grid lines 111 may increase the number of welding points between the connecting component 120 and the battery cell, thereby improving the welding quality between the battery cell and the connecting component 120 .

[0061] For example, the number of the welding grid lines 111 may be 2, 3, 4 or 5.

[0062] In some embodiments, the shape of the welding grid line 111 can be any one of an arc shape, a straight line shape, a folded line shape or a wavy shape.

[0063] Figure 4 Four schematic diagrams of welding grid lines in a photovoltaic module provided in an embodiment of the present application.

[0064] refer to Figure 4 The number and shape of welding grid lines can be Figure 4 Any one of (a~d) is not limited to it in the embodiments of the present application.

[0065] The width of each welding grid line and the spacing range between each welding grid line are not limited in this application, and those skilled in the art can set them according to actual needs.

[0066] Figure 5 A top view of a welded grid line in a photovoltaic module provided in one embodiment of the present application.

[0067] refer to Figure 5In some embodiments, the welding grid lines 111 include first-type grid lines 1111 and second-type grid lines 1112. The first-type grid lines 1111 and the collecting grid lines 112 are made of a burn-through paste, and the second-type grid lines 1112 are made of a non-burn-through paste. In this way, the first-type grid lines 1111 are used to collect carriers and are welded to the connecting component 120. The second-type grid lines 1112 are used to weld to the connecting component 120 and have good welding tension, so that they can have higher welding quality and lower power generation loss.

[0068] The burn-through paste refers to the electrode paste that can burn through the passivation layer of the cell and electrically connect to the doping layer, for example, welding the gate line to electrically connect the emitter. The non-burn-through paste refers to the electrode paste that cannot burn through the passivation layer.

[0069] It should be noted that the first type gate lines 1111 and the collecting gate lines 112 can be integrally formed gate lines, and the first type gate lines 1111 and the collecting gate lines 112 can be printed in the same printing process, and then the second type gate lines 1112 can be printed in another printing process. In some embodiments, the first type gate lines, the collecting gate lines, and the second type gate lines can also be printed separately.

[0070] Figure 6 A partial cross-sectional view of a photovoltaic assembly provided in one embodiment of the present application.

[0071] In some embodiments, reference Figure 6 The welding grid line 111 includes: a stacked first sub-grid line 131 and a second sub-grid line 132, the second sub-grid line 132 is located between the connecting component 120 and the first sub-grid line 131, and the first sub-grid line 131 and the second sub-grid line 132 are made of different materials. By setting the stacked first sub-grid line 131 and the second sub-grid line 132, the first sub-grid line 131 and the second sub-grid line 132 are made of different materials, so that the first sub-grid line 131 can be set to burn through the passivation layer and contact the doping layer, thereby collecting carriers, thereby having a greater photoelectric conversion efficiency; and the second sub-grid line 132 located on the first sub-grid line 131 is used for welding with the connecting component 120, and the second sub-grid line 132 and the connecting component 120 have good compatibility in the molten state, thereby having better welding quality and higher welding tension, avoiding the problem of power generation loss caused by the separation of the connecting component 120 and the battery cell 100.

[0072] For example, the material of the first sub-grid line 131 may be silver-aluminum material, and the material of the second sub-grid line 132 may be silver material. For another example, the material of the first sub-grid line 131 may be silver-aluminum material, and the material of the second sub-grid line 132 may be solder paste.

[0073] It should be noted that Figure 6The fact that the height of the first sub-gate line 131 is consistent with the height of the collecting gate line 112 is only for illustration. In practice, the surface of the first sub-gate line 131 may be lower than the surface of the collecting gate line 112 or flush with the surface of the first sub-gate line 131 , or even higher than the height of the collecting gate line 112 .

[0074] Figure 7 Another top view of a welded grid line in a photovoltaic module provided by an embodiment of the present application; Figure 8 for Figure 7 A corresponding cross-sectional view.

[0075] In some embodiments, at least two welding gate lines 111 of the same first gate line contact each other to form a pad 113, and the width of the pad 113 along the second direction is greater than the width of the collecting gate line 112 along the second direction. In this way, electrical connection is achieved through the pad 113 and the connecting component 120. Compared with a single gate line, the width of the pad 113 is larger, thereby avoiding the problem of gate line breakage and the problem of insufficient welding tension, thereby improving welding quality.

[0076] In addition, compared with a plurality of welding grid lines 111 , the operable window of the welding pad 113 is larger, thereby reducing the process difficulty of the battery cell and improving the accuracy and precision, thereby improving the yield and aesthetics of the photovoltaic module.

[0077] The connection component 120 is used to realize the interconnection between the cells 100 and gather the current to transmit to the components outside the photovoltaic module. The connection component 120 includes a busbar and an interconnection ribbon. The busbar is used to connect the photovoltaic cell string and the junction box, and the interconnection ribbon is used to connect the first cell and the second cell.

[0078] In some embodiments, the connecting component 120 is a core-wrapped structure, and the connecting component 120 includes a conductive layer and a solder layer covering the surface of the conductive layer. The conductive layer is the main conductive transmission layer of the connecting component 120. Therefore, the lower the resistivity of the conductive layer, the smaller the electrical loss of the connecting component 120, and the better the battery efficiency and power generation. The material of the conductive layer is a conductive material with good conductivity such as copper, nickel, gold, silver, or an alloy material with low resistivity.

[0079] In some embodiments, the solder layer may be plated or coated on the surface of the conductive layer. Specifically, the source material of the solder layer may be uniformly coated around the conductive layer according to a certain composition ratio and thickness by using special processes such as electroplating, vacuum deposition, spraying or hot dip coating. The main function of the solder layer is to make the connection component 120 meet the weldability and firmly weld the connection component 120 to the grid line structure of the battery cell 100, so as to play a good role in current conduction.

[0080] In some embodiments, the material of the solder layer is a metal material or alloy material with a lower melting point than the conductive layer, such as a tin alloy, which may include a tin-zinc alloy, a tin-bismuth alloy, or a tin-indium alloy. Tin is used as a soldering material, and tin has a low melting point, good affinity with metals such as copper, and good soldering fastness. The lead in the tin-lead alloy can reduce the melting point of the solder strip, and tin and lead can form a eutectic point with a melting point of 183°C, and have good soldering performance and performance.

[0081] The embodiments disclosed in the present 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 reduce the melting point temperature and reduce the surface tension. The melting point of the tin-bismuth alloy can be reduced to 129°C, meeting the requirements of low-temperature welding. In this way, the stress of thermal expansion and contraction of the connecting component 120 can be reduced, reducing the risk and probability of the welding grid line 111 being broken.

[0082] In some embodiments, the solder layer contains flux, which refers to a chemical substance that can help and promote the soldering process in the soldering process, and has a protective effect and prevents oxidation reactions. The flux includes inorganic flux, organic flux and resin flux. It is understood that the melting point of the flux is lower than the melting point of the solder layer, and increases the fluidity of the molten solder layer so that the solder layer and the grid line structure form a good alloy.

[0083] In some embodiments, along a section perpendicular to the first direction Y, the cross-sectional shape of the connecting component 120 is circular, and circular welding strips do not have orientation and alignment problems, and circular welding strips are easier to mass produce.

[0084] In some embodiments, the cross-sectional shape of the connection component 120 may be a triangle or any other shape to increase the contact area between the soldering ribbon and the gate line structure and reduce the problem of alignment deviation between the connection component 120 and the gate line structure.

[0085] In some embodiments, the surface of the connection component 120 away from the cell has a reflective layer, which is located on the outer side of the solder layer away from the conductive layer and the cell. The reflective layer is used to improve the electrical loss caused by the shielding area of ​​the cell by the connection component 120.

[0086] In some embodiments, the outer surface of the solder layer has reflective grooves, which are recessed grooves or grooves extending from the solder layer toward the conductive layer. Sunlight is reflected onto the battery cell through the side walls of the reflective grooves, thereby improving the utilization rate of sunlight.

[0087] In some embodiments, continue to refer to Figure 1 The photovoltaic module further includes a battery string, which is composed of a plurality of battery cells in the above-mentioned embodiments through a connecting component 120, wherein the connecting component 120 is used to connect adjacent battery cells 100 in series.

[0088] In some embodiments, the battery cell includes a first battery cell and a second battery cell. The connecting component 120 connects the first electrode of the first battery cell and the second electrode of the adjacent second battery cell, or the connecting component 120 connects the second electrode of the first battery cell and the first electrode of the adjacent second battery cell. The first electrode is one of the positive electrode or the negative electrode, and the second electrode is the other of the positive electrode or the negative electrode.

[0089] In some embodiments, reference Figure 1 , the front sides of the first battery cell and the second battery cell are facing the same side, and the back sides of the first battery cell and the second battery cell are facing the same side, or in other words, the first electrodes of all battery cells 100 are facing the same side, and the second electrodes of all battery cells 100 are facing the same side, then the connecting component 120 needs to naturally extend from the front side of the battery cell to the back side of the adjacent battery cell, so that the connecting component 120 connects the first electrode and the second electrode of the adjacent battery cell.

[0090] In other embodiments, the first battery cell and the second battery cell are arranged in the order of the first surface, the second surface, the first surface and the second surface, and the connecting component will not bend, and the connecting component directly connects the first electrode of the first battery cell and the second electrode of the second battery cell adjacent thereto.

[0091] in, Figure 1 There is a cell gap between adjacent battery cells 100 shown in the figure to achieve electrical insulation between different battery cells 100. In other embodiments, there is no cell gap between adjacent battery cells, that is, the battery cells are stacked.

[0092] Continue to refer Figure 1 The photovoltaic module further includes: an adhesive film 11, which covers the surface of the battery string and fills the gaps between the battery strings. The photovoltaic module further includes: a cover plate 12, which covers the side of the adhesive film 11 away from the battery string.

[0093] The material of the film 11 includes organic packaging films such as EVA, POE or PVB.

[0094] In some embodiments, the glass transition temperature of the adhesive film 11 is -70 to -10°C. The glass transition temperature of the adhesive film is used to ensure that the adhesive film can be in a molten state during the lamination process to fill the gaps of the photovoltaic module and improve the yield of the photovoltaic module.

[0095] In some embodiments, the melting point of the adhesive film and the melting point of the connecting component 120 can be set according to actual needs. When the melting point of the adhesive film 11 is greater than the melting point of the connecting component 120, the connecting component 120 can be alloyed before the adhesive film 11 is molten, which can effectively prevent the molten adhesive film 11 from dipping into the welding grid line 111 and the connecting component 120 and pushing the connecting component 120 to cause it to deviate. When the melting point of the adhesive film 11 is less than the melting point of the connecting component 120, the lamination temperature can be set lower to improve the thermal stress on the battery cell 100 and improve the yield of the photovoltaic module.

[0096] In some embodiments, the cover plate 12 may be a glass cover plate, a plastic cover plate or the like with a light-transmitting function. Specifically, the surface of the cover plate 12 away from the adhesive film 11 may be a concave-convex surface, thereby increasing the utilization rate of the incident light. The cover plate 12 includes a first cover plate and a second cover plate, the first cover plate is opposite to the front side of the battery cell, and the second cover plate is opposite to the back side of the battery cell.

[0097] The photovoltaic module provided by the embodiment of the present application comprises a plurality of grid lines and a connecting component 120 arranged along the second direction on the surface of the cell. The connecting component 120 is welded and connected to each welding grid line 111. The welding grid lines 111 are welded and connected to the connecting component 120. The number of welding grid lines 111 is large, that is, the number of welding points between the cell and the connecting component 120 is large, so that the welding tension between the cell and the connecting component 120 can be increased, and the problem of the connecting component 120 being separated from the cell can be avoided, and the problem of poor EL appearance and power generation loss caused by cold welding can be avoided. A collecting grid line 112 is electrically connected to a plurality of welding grid lines 111. In this way, the grid lines on the cell can be connected to the connecting component 120 through multiple paths, effectively avoiding the situation of power generation loss caused by the broken grid problem.

[0098] Correspondingly, another embodiment of the present application further provides a battery cell, which is different from the above embodiment in that the battery cell in the above embodiment is a non-back-contact battery cell, that is, one side of the battery cell has a gate line of one conductive type, while another embodiment of the present application provides a back-contact battery cell, one side of the battery cell has a first gate line of the first conductive type and a second gate line of the second conductive type. The parts that are the same or corresponding to the above embodiment will not be described in detail here.

[0099] Fig. 9 A schematic structural diagram of a photovoltaic module provided in another embodiment of the present application; Fig.10 A top view of a photovoltaic assembly provided in another embodiment of the present application.

[0100] Another embodiment of the present application provides a photovoltaic module for reducing power generation losses. Fig. 9 and Fig.10The photovoltaic module includes: a battery cell 200, and the battery cell 200 includes a welding area and a collecting area arranged along a first direction X.

[0101] In some embodiments, the cell 200 is a back-contact cell, such as an interdigitated back contact crystalline silicon solar cell (IBC). An IBC cell refers to a back-junction back-contact solar cell structure in which positive and negative metal electrodes are arranged in an interdigitated manner on the backlight side 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 blocking the front, which can improve the photoelectric conversion performance of the cell.

[0102] refer to Fig.10 The welding area may include a first welding area 2011 and a second welding area 2012 , and the collecting area may include a first collecting area 2021 and a second collecting area 2022 .

[0103] The surface of the battery cell 200 has multiple grid lines arranged along the second direction, each grid line includes at least two welding grid lines located in the welding area and a collecting grid line located in the collecting area, wherein the welding grid lines are arranged along the second direction, and each of the at least two welding grid lines is electrically connected to the same collecting grid line.

[0104] In some embodiments, reference Fig.10 The gate lines include a first gate line 240 of a first conductive type and a second gate line 250 of a second conductive type. The first gate line 240 includes a first welding gate line 241 corresponding to the first welding area 2011 and a first collecting gate line 242 corresponding to the first collecting area. The second gate line 250 includes a second welding gate line 251 corresponding to the second welding area 2012 and a second collecting gate line 252 corresponding to the second collecting area 2022. The first welding area 2011 is opposite to the second collecting area 2022 along the second direction Y, and the second welding area 2012 is opposite to the first collecting area 2021 along the second direction Y.

[0105] refer to Fig.10 The photovoltaic module includes: a connecting component, which is located on the solar cell. The connecting component includes a first connecting component 221 and a second connecting component 222. The first connecting component 221 is electrically connected to a plurality of first grid lines 240 arranged along the second direction Y, and the first connecting component 221 is welded to each first welding grid line 241; the second connecting component 222 is electrically connected to a plurality of second grid lines 250 arranged along the second direction Y, and the second connecting component 222 is welded to each second welding grid line 251.

[0106] Continue to refer Fig.10The photovoltaic module further includes an insulating layer 260 , and the insulating layer 260 is located between the first connection component 221 and the second collection grid line 252 . The insulating layer 260 is located between the second connection component 222 and the first collection grid line 242 .

[0107] In some embodiments, the insulating layer 260 is an independent rubber block, corresponding to between the first connecting component 221 and the second collecting gate line 252 and between the second connecting component 222 and the first collecting gate line 242, so as to reduce the amount of the insulating layer 260 and reduce the preparation cost.

[0108] The parameters such as the size, length and thickness of the insulating layer 260 in the embodiment of the present application are not limited in the embodiment of the present application. It is only necessary to ensure electrical insulation between the corresponding first connecting component 221 and the second collecting gate line 252 and electrical insulation between the second connecting component 222 and the first collecting gate line 242.

[0109] In some embodiments, the insulating layer 260 not only covers the first welding area 2011, but also extends beyond the first welding area 2011 and to a partial width of the first collection area 2021, where the width extended to the first collection area 2021 is 0.5 mm to 2.5 mm. This reduces the difficulty of series welding and effectively avoids the risk of short circuit.

[0110] For example, the width of the insulating layer 260 extending to the first collection area 2021 is 0.5 mm, 0.8 mm, 1.0 mm, 1.2 mm, 1.4 mm, 1.6 mm, 1.8 mm, 2.0 mm, 2.2 mm, 2.4 mm or 2.5 mm.

[0111] Similarly, the insulating layer 260 not only covers the second welding area 2012 , but also extends to the second collecting area 2022 , and the extension width is 0.5 mm to 2.5 mm.

[0112] Fig.11 Another top view of a photovoltaic module provided by another embodiment of the present application; Fig.12 for Fig.11 A partial cross-sectional view of Fig.13 for Fig.11 Another partial cross-sectional view of .

[0113] In some embodiments, reference Fig.11, the insulating layer 260 is located on the first grid line 240 and the second grid line 250, and the insulating layer 260 has a hollow area 261, the hollow area 261 corresponds to the first welding area 2011, and the hollow area 261 exposes the first welding grid line 241. The hollow area also corresponds to the second welding area 2012, and the hollow area 261 exposes the second welding grid line 251. In this way, an entire insulating layer 260 is provided, and the hollow area 261 is provided through the corresponding area to achieve the electrical connection between the first connecting component 221 and the first welding grid line 241, and the electrical connection between the second connecting component 222 and the second welding grid line 251, which reduces the difficulty of printing the insulating layer blocks one by one and the alignment requirements, thereby reducing the process difficulty.

[0114] In some embodiments, the insulating layer 260 covers the first welding area 2011, and also extends beyond the first welding area 2011 and to a first collection area 2021 of a partial width, and the width extending to the first collection area 2021 is 0.5mm to 2.5mm; another insulating layer 260 covers the second welding area 2012, and also extends beyond the second welding area 2012 and to a second collection area 2022 of a partial width, and the width extending to the second collection area 2022 is 0.5mm to 2.5mm. In this way, the difficulty of serial welding is reduced, and the risk of short circuit is effectively avoided.

[0115] In some embodiments, at least two first welding grid lines 241 of the same first grid line 240 contact each other to form a pad, and the width of the pad along the second direction is greater than the width of the first collecting grid line 242 along the second direction Y. In this way, electrical connection is achieved through the pad and the connecting component. Compared with a single grid line, the width of the pad is larger, thereby avoiding the problem of grid breakage and insufficient welding tension, thereby improving the welding quality. In addition, compared with multiple welding grid lines, the operable window of the pad is larger, thereby reducing the process difficulty of the battery cell, and improving the accuracy and accuracy rate, thereby improving the yield and aesthetics of the photovoltaic module.

[0116] Similarly, in some embodiments, at least two second welding gate lines 251 of the same second gate line 250 contact each other to form a pad, and the width of the pad along the second direction is greater than the width of the second collecting gate line 252 along the second direction Y.

[0117] In some embodiments, reference Fig.13 , corresponding to the area of ​​the connection component, the top surface of the first welding line 241 close to the insulating layer 260 is higher than the top surface of the first welding line 241 away from the insulating layer 260, that is, the height h1 of the first welding line 241 close to the insulating layer 260 can be greater than the height h2 of the first welding line 241 away from the insulating layer 260. Fig.12 and Fig.13It can be seen that since the height h1 of the first welding grid line 241 close to the insulating layer 260 is slightly higher, the contact area between the first connecting member 221 and the top surface of the first welding grid line 241 close to the insulating layer 260 becomes larger, thereby improving the welding quality and increasing the welding tension.

[0118] In some embodiments, the width of the first welding wire 241 close to the insulating layer 260 may be greater than the width of the first welding wire 241 far from the insulating layer 260 .

[0119] In some embodiments, the distance between the insulating layer 260 and the first welding grid line 241 is proportional to the thickness of the insulating layer 260, that is, the thickness of the insulating layer 260 is larger, the distance between the insulating layer 260 and the first welding grid line 241 is larger, and the area opened by the hollow region is larger, so that the first connecting component 221 has a larger space to deform and the contact area between the connecting component and the first welding grid line 241 is larger. On the contrary, the thickness of the insulating layer 260 is smaller, the distance between the insulating layer 260 and the first welding grid line 241 is smaller, and the area opened by the hollow region is smaller.

[0120] In some embodiments, the thickness of the insulating layer 260 decreases along the second direction Y and toward the first welding grid line 241. In this way, the first connecting member 221 can be welded to the first welding grid line 241 along the thickness variation trend of the insulating layer 260 to increase the welding area and avoid the problem of cold welding.

[0121] Fig.14 A partial top view of a photovoltaic assembly provided in another embodiment of the present application.

[0122] In some embodiments, the first collecting gate line 242 includes two first broken gates 206 and a first break 205 between the two first broken gates 206 , the first break 205 corresponds to the second welding area 2012 , and the first broken gate 206 is located on both sides of the second connecting component and is insulated from the second connecting component.

[0123] The second collecting gate line 252 includes two broken gates 204 and a break 203 between the two broken gates 204 . The break 203 corresponds to the first welding area 2011 . The broken gates 204 are located on both sides of the first connecting component and are insulated from the first connecting component.

[0124] In some embodiments, continue to refer to Fig. 9 The photovoltaic module also includes a battery string, which is composed of a plurality of battery cells in the above embodiments through a connecting component, wherein the connecting component is used to connect adjacent battery cells in series.

[0125] In some embodiments, the battery cell includes a first battery cell and a second battery cell. The connecting component 220 connects the first welding grid line 241 of the first battery cell and the second welding grid line 251 of the adjacent second battery cell, or the connecting component 220 connects the second welding grid line 251 of the first battery cell and the first welding grid line 241 of the adjacent second battery cell.

[0126] Continue to refer Fig. 9 The photovoltaic module further includes: an adhesive film 21, which covers the surface of the battery string and fills the gaps between the battery strings. The photovoltaic module further includes: a cover plate 22, which covers the side of the adhesive film 21 away from the battery string.

[0127] The photovoltaic module provided by the embodiment of the present application comprises a plurality of first grid lines 240 arranged along the second direction, a first grid line 240, a first connecting component 221 and a second connecting component 222 on the surface of the cell, the first connecting component 221 is welded and connected to each first welding grid line 241, and the second connecting component 222 is electrically connected to the second welding grid line 251. The first welding grid lines 241 are electrically connected to the first connecting component 221 and the second welding grid lines 251 are welded and connected to the second connecting component 222, and the number of the first welding grid lines 241 and the number of the second welding grid lines 251 are large, that is, the number of welding points between the cell and the first connecting component 221 is large and the number of the cell and the second connecting component 222 is large, so that the welding tension between the cell and the connecting component can be increased, the problem of the connecting component being separated from the cell can be avoided, and the problem of poor EL appearance and power generation loss caused by cold welding can be avoided. A first collecting grid line 242 is electrically connected to a plurality of first welding grid lines 241, so that the first grid lines on the battery cell can be connected to the first connecting component 221 through a plurality of paths, effectively avoiding power generation loss due to grid breakage.

[0128] Those skilled in the art will appreciate that the above-mentioned embodiments are specific examples for implementing the present application, and in practical applications, various changes may be made to the embodiments in form and detail without departing from the spirit and scope of the present application. Any person skilled in the art may make various changes and modifications without departing from the spirit and scope of the present application, and therefore the scope of protection of the present application shall be subject to the scope defined in the claims.

Claims

1. A photovoltaic module, characterized in that: include: A battery cell, wherein the battery cell comprises a welding area and a collecting area arranged along a first direction; The surface of the battery cell has a plurality of grid lines arranged along the second direction, each of the grid lines includes at least two welding grid lines located in the welding area and a collecting grid line located in the collecting area, wherein the welding grid lines are arranged along the second direction, and each of the at least two welding grid lines is electrically connected to the same collecting grid line; A connecting component is located on the battery cell, the connecting component is electrically connected to a plurality of the grid lines arranged along the second direction, and the connecting component is welded to each of the welding grid lines.

2. The photovoltaic module according to claim 1, characterized in that: The width of the welding grid line along the second direction is greater than or equal to the width of the collecting grid line along the second direction.

3. The photovoltaic module according to claim 1, characterized in that: The welding grid lines include first-type grid lines and second-type grid lines. The first-type grid lines and the collecting grid lines are formed of a burn-through paste, and the second-type grid lines are formed of a non-burn-through paste.

4. The photovoltaic module according to claim 1 or 3, characterized in that: The welding grid line includes: a stacked first sub-grid line and a second sub-grid line, the second sub-grid line is located between the connecting component and the first sub-grid line, and the first sub-grid line and the second sub-grid line are made of different materials.

5. The photovoltaic module according to claim 1, characterized in that: The battery cell is a back contact battery cell, the grid lines include a first grid line of a first conductive type and a second grid line of a second conductive type, the first grid lines include a first welding grid line corresponding to the first welding area and a first collecting grid line corresponding to the first collecting area, the second grid lines include a second welding grid line corresponding to the second welding area and a second collecting grid line corresponding to the second collecting area, the first welding area is directly opposite to the second collecting area along the second direction, and the second welding area is directly opposite to the first collecting area along the second direction; The invention also includes an insulating layer, wherein the insulating layer is located between the connecting component and the second collecting gate line.

6. The photovoltaic module according to claim 5, characterized in that: The insulating layer is located on the first gate line and the second gate line, and the region of the insulating layer corresponding to the first welding region exposes the first welding gate line.

7. The photovoltaic module according to claim 5 or 6, characterized in that: At least two of the first welding gate lines of the same first gate line contact each other to form a pad, and a width of the pad along the second direction is greater than a width of the first collecting gate line along the second direction.

8. The photovoltaic module according to claim 5 or 6, characterized in that: In a region corresponding to the connection component, a top surface of the first welding wire close to the insulating layer is higher than a top surface of the first welding wire far from the insulating layer.

9. The photovoltaic module according to claim 6, characterized in that: The distance between the insulating layer and the first welding grid line is proportional to the thickness of the insulating layer.

10. The photovoltaic module according to claim 6, characterized in that: Along the second direction and toward the first welding grid line, the thickness of the insulating layer decreases gradually.

11. The photovoltaic module according to claim 6, characterized in that: The second collecting gate line includes two broken gates and a break located between the two broken gates, the break corresponding to the first welding area, and the broken gates are located on both sides of the connecting component and are insulated from the connecting component.

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