Photovoltaic module

Abstract

The embodiment of the present application relates to the photovoltaic field, and provides a photovoltaic module, the photovoltaic module comprises: a cell piece, the cell piece comprises a welding area and a collection area arranged along a first direction; the surface of the cell piece has a plurality of grid lines arranged along a 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, wherein the welding grid lines are arranged along 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; a connecting component is located on the cell piece, the connecting component is electrically connected with the plurality of grid lines arranged along the second direction, and the connecting component is welded with each welding grid line. The photovoltaic module provided by the embodiment of the present application can at least reduce power generation loss.

Description

TECHNICAL FIELD

[0001] Embodiments of the present application relate to the field of photovoltaics, and in particular to a photovoltaic module. BACKGROUND

[0002] A solar cell is a device that converts light energy directly into electricity through the photovoltaic effect or photochemical effect. A single solar cell cannot generate electricity directly for use. It must be connected in series and parallel through a solder strip and tightly packaged into a module for use. The solar cell module (also called a solar panel) is the core part of a solar power generation system and is the most important part of the solar power generation system. The role of the solar cell module is to convert solar energy into electrical energy, or to store it in a storage battery, or to drive the load to work.

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

[0004] However, the front grid lines (main grid lines and fine grid lines) will block a portion of the silicon wafer, and the light energy that shines on the grid lines cannot be converted into electrical energy, resulting in waste, and the main component of the paste used to make the grid lines is silver, a noble metal with a high price, so it also involves cost issues. Based on this, technicians have made more and thinner connecting components directly link the cell fine grid to collect current while achieving cell interconnection, eliminating the traditional main grid at the cell level, i.e., busbar-free technology. However, there are still many factors that affect the yield and power generation loss of photovoltaic modules, such as the welding effect and welding yield between the connecting component and the fine grid. SUMMARY

[0005] Embodiments of the present application provide a photovoltaic module, which at least helps to reduce power generation loss.

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

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

[0008] In some embodiments, the soldering grid line comprises a first type of grid line and a second type of grid line, the first type of grid line is composed of a burn-through type paste, and the second type of grid line is composed of a non-burn-through type paste.

[0009] In some embodiments, the soldering grid line comprises a first sub-grid line and a second sub-grid line stacked, the second sub-grid line is located between the connecting component and the first sub-grid line, and the materials of the first sub-grid line and the second sub-grid line are different.

[0010] In some embodiments, the battery piece is a back contact battery piece, the grid line comprises a first grid line of a first conductive type and a second grid line of a second conductive type, the first grid line comprises a first soldering grid line corresponding to a first soldering area and a first collecting grid line corresponding to a first collecting area, the second grid line comprises a second soldering grid line corresponding to a second soldering area and a second collecting grid line corresponding to a second collecting area, the first soldering area and the second collecting area are opposite to each other along the second direction, and the second soldering area and the first collecting area are opposite to each other along the second direction; further comprising: an insulating layer located between the connecting component and the second collecting grid line.

[0011] In some embodiments, the insulating layer is located on the first grid line and the second grid line, and the area of the insulating layer corresponding to the first soldering area exposes the first soldering grid line.

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

[0013] In some embodiments, the top surface of the first soldering grid line close to the insulating layer is higher than the top surface of the first soldering grid line away from the insulating layer in the area corresponding to the connecting component.

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

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

[0016] In some embodiments, the second collecting grid line comprises two broken grid lines and a breakage located between the two broken grid lines, the breakage corresponds to the first soldering area, and the broken grid lines are located on both sides of the connecting component and are insulated from the connecting component.

[0017] The technical scheme 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, the surface of the cell piece comprises a plurality of grid lines arranged along a second direction and a connecting component, the connecting component is welded with each soldering grid line, the soldering grid line is welded with the connecting component through the soldering grid line, the number of soldering grid lines is relatively large, that is, the number of welding points between the cell piece and the connecting component is relatively large, so that the welding tension between the cell piece and the connecting component can be improved, the problem that the connecting component is separated from the cell piece is avoided, and the problems of EL appearance defect and power generation loss caused by virtual welding are avoided. One collecting grid line is electrically connected with a plurality of soldering grid lines, in this way, the grid lines on the cell piece can be connected with the connecting component through a plurality of paths, and the power generation loss caused by the broken grid problem is effectively avoided. BRIEF DESCRIPTION OF DRAWINGS

[0019] One or more embodiments are illustrated by way of example in the figures that form a part of this disclosure and which are not intended to limit the application unless otherwise specifically indicated, the drawings shown in the figures are not to scale; in order to more clearly illustrate the technical solutions in the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the embodiments will be briefly introduced below, obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0020] Figure 1 A structural schematic diagram of a photovoltaic module provided by an embodiment of the present application;

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

[0022] Figure 3 A partial sectional view of Figure 2 ;

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

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

[0025] Figure 6 A partial sectional view of a photovoltaic module provided by an embodiment of the present application;

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

[0027] Figure 8 A corresponding sectional view of Figure 7 ;

[0028] Figure 9 A structural schematic diagram of a photovoltaic module provided for another embodiment of the present application;

[0029] Figure 10 A top view of a photovoltaic module provided for another embodiment of the present application;

[0030] Figure 11 Another top view of a photovoltaic module provided for another embodiment of the present application;

[0031] Figure 12 A partial sectional view of Figure 11

[0032] Another partial sectional view of Figure 13 Figure 11

[0033] Figure 14 A partial top view of a photovoltaic module provided for another embodiment of the present application. DETAILED DESCRIPTION

[0034] As known from the background art, the power generation loss of the current photovoltaic module is large.

[0035] It is found by analysis that one of the reasons for the current power generation loss is that the mainstream silver electrode is a combination of silver and glass body, and the structure is loose and not stable enough, and in addition, the melting point is different from that of the copper welding strip. If 0BB technology is used, the single-point welding area is reduced by 90%, and the welding strip and the cell piece are easy to separate due to external force or thermal expansion and cold contraction, resulting in power generation loss.

[0036] The embodiment of the present application provides a photovoltaic module, by arranging welding grid lines, and welding the plurality of welding grid lines and the connecting component, so as to increase the welding area between the connecting component and the cell piece, and then facilitate to improve the welding tension, so as to avoid the false welding of the connecting component and the separation of the connecting component from the cell piece, and facilitate to improve the yield of the photovoltaic module and the cell 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 "a plurality of" is two or more, unless otherwise specifically limited.

[0038] ​​Reference to“an embodiment” herein means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase“in an embodiment” in various places in the specification are not necessarily referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. As will be apparent to those of ordinary skill in the art, embodiments described herein can be combined with other embodiments.

[0039] In the description of the embodiments of the application, the term“and / or” only means an association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which can mean that A exists, A and B exist, and B exists. In addition, the character“ / ” herein generally means that the front and rear associated objects are in an“or” relationship.

[0040] In the description of the embodiments of the application, the term“a plurality of” refers to two or more (including two), and similarly, “a plurality of groups” refers to two or more groups (including two groups), and “a plurality of pieces” refers to two or more pieces (including two pieces).

[0041] In the description of the embodiments of the application, the technical terms“center”,“longitudinal”,“transverse”,“length”,“width”,“thickness”,“upper”,“lower”,“front”,“rear”,“left”,“right”,“vertical”,“horizontal”,“top”,“bottom”,“inner”,“outer”,“clockwise”,“counterclockwise”,“axial”,“radial”,“circumferential” and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the embodiments of the application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the embodiments of the application.

[0042] In the description of the embodiments of the application, unless otherwise explicitly specified and limited, the technical terms“mounting”,“connection”,“connection”,“fixing” and the like should be understood broadly, for example, can be fixedly connected, or can be detachably connected, or can be integrated; can be mechanically connected, or can be electrically connected; can be directly connected, or can be indirectly connected through an intermediate medium; can be the internal communication 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 application can be understood according to the specific circumstances.

[0043] In the accompanying drawings corresponding to the embodiments of this application, the thickness and area of ​​the layers are enlarged for better understanding and ease of description. When describing a component (such as a layer, film, region, or substrate) on or on the surface of another component, the component may be "directly" located on the surface of the other component, or there may be a third component between the two components. Conversely, when describing a component on the surface of another component, or when another component is formed or disposed on the surface of a component, it indicates that there is no third component between the two components. Furthermore, when describing a component as being "generally" 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 portion of the edge of the entire surface.

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

[0045] The terminology used in the description of the various embodiments herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used in the description of the various embodiments and the appended claims, the term "part" is also intended to include the plural form unless the context clearly indicates otherwise. Components include layers, films, regions, or plates, etc.

[0046] 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.

[0047] Figure 1 This is a schematic diagram of a photovoltaic module provided in one embodiment of this application; Figure 2 A top view of a photovoltaic module provided in an embodiment of this application; Figure 3 for Figure 2 A partial sectional view. Among them, Figure 2 The connecting parts are semi-transparent, and the adhesive film and cover plate are transparent, meaning that the welding grid lines located under the connecting parts can be seen through the connecting parts. Figure 3The cross-sectional view in the figure does not show the adhesive film and the cover plate. In practice, the gap between the two solder grid lines has an adhesive film.

[0048] Embodiments of the present application provide a photovoltaic module for reducing power generation loss. Referring to Figure 1 and Figure 2 The photovoltaic module includes a cell 100, the cell 100 includes a soldering 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 soldering grid lines 111 located in the soldering area 101 and a collecting grid line 112 located in the collecting area 102, wherein the soldering grid lines 111 are arranged along the second direction Y, and each soldering grid line 111 of the at least two soldering 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 soldered to each soldering grid line 111.

[0049] The photovoltaic module provided by the embodiments of the present application, the surface of the cell 100 includes a plurality of grid lines 110 arranged along the second direction Y and a connecting component 120, the connecting component 120 is soldered to each soldering grid line 111, by soldering the soldering grid line 111 to the connecting component 120, the number of soldering grid lines 111 is more, that is, the number of soldering points between the cell 100 and the connecting component 120 is more, so as to improve the soldering tension between the cell 100 and the connecting component 120, avoid the problem that the connecting component 120 is separated from the cell 100, and avoid the problem of EL appearance defect and power generation loss caused by false welding. One collecting grid line 112 is electrically connected to a plurality of soldering 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 power generation loss caused by the problem of broken grid.

[0050] In some embodiments, the cell 100 can 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 battery piece 100 can be a monocrystalline silicon solar cell, a polycrystalline silicon solar cell, an amorphous silicon solar cell, or a multi-element compound solar cell, which can be a cadmium sulfide solar cell, a gallium arsenide solar cell, a copper indium selenium solar cell, or a perovskite solar cell.

[0052] In some embodiments, the battery piece 100 is a whole battery or a cut battery. The cut battery refers to a battery piece formed by cutting a whole battery. 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 cut battery is a half battery, which can also be understood as a cut-half battery or a two-piece battery. The cut-half battery assembly functions to improve power generation by reducing resistance loss. The cut-half battery assembly can optimize the width of the connecting component 120, which is conventionally optimized between increasing the width of the connecting component 120 to reduce power generation loss and reducing the width of the connecting component 120 to reduce shading loss. The cut-half battery assembly reduces battery loss, so the width of the connecting component 120 can be set thinner to reduce shading loss, which is beneficial to improve battery efficiency and power generation. In other embodiments, the cut battery can be a three-piece battery, a 4-piece battery, or an 8-piece battery, etc.

[0054] The welding area 101 refers to the area where the connecting component 120 is welded with the battery piece. In order to make the area contacted by the connecting component 120 be the welding area 101, the area of the welding area 101 is generally set to be larger than the area of the connecting component 120, so that Figure 2 The width of the connecting component 120 shown is less than the width of the welding area 101.

[0055] The collection area 102 refers to the area of the battery piece other than the welding area 101, which is used to collect and aggregate current.

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

[0057] The welding grid line 111 is used to form alloy contact with the connecting component 120, thereby achieving the purpose of welding. The alloy contact between the welding grid line 111 and the connecting component 120 can be formed by welding or lamination.

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

[0059] In some other embodiments, the width of the solder grid line 111 is greater than the width of the collecting grid line 112. The width of the solder grid line 111 is set to be greater, so that the contact area between the connecting component 120 and the solder grid line 111 is greater. In this way, the performance of the alloy contact between the connecting component 120 and the solder grid line 111 can be improved, thereby improving the soldering quality, avoiding the problem of false soldering, and avoiding the problem of power generation loss caused by the separation of the connecting component 120 from the battery piece. In addition, the width of the solder grid line 111 is greater, so that the probability of the solder grid line 111 being broken due to thermal expansion and contraction of the tin layer on the connecting component 120 during the soldering process is reduced, thereby improving the EL appearance and reducing the power generation loss.

[0060] In some embodiments, the number of solder grid lines 111 can be 2-5. The greater the number of solder grid lines 111, the greater the number of soldering points between the connecting component 120 and the battery piece, thereby improving the soldering quality between the battery piece and the connecting component 120.

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

[0062] In some embodiments, the shape of the solder grid line 111 can be any one of a circular arc, a straight line, a broken line, or a wave shape.

[0063] Figure 4 Four schematic diagrams of a solder grid line in a photovoltaic module according to an embodiment of the present application.

[0064] Reference Figure 4 The number and shape of the solder grid lines can be any one of Figure 4 (a-d), and the embodiments of the present application do not limit them.

[0065] The width of each solder grid line and the spacing between each solder grid line are not limited by the present application, and can be set according to actual needs by those skilled in the art.

[0066] Figure 5 A top view of a solder grid line in a photovoltaic module according to an embodiment of the present application.

[0067] Reference Figure 5In some embodiments, the soldering grid lines 111 include first type grid lines 1111 and second type grid lines 1112, the first type grid lines 1111 are made of the burn-through paste, and the second type grid lines 1112 are made of the non-burn-through paste. In this way, the first type grid lines 1111 are used for collecting carriers and soldering with the connecting components 120. The second type grid lines 1112 are used for soldering with the connecting components 120 and have better soldering tension, so as to have higher soldering quality and lower power generation loss.

[0068] The burn-through paste refers to an electrode paste that can burn through the passivation layer of the battery piece and be electrically connected with the doped layer, for example, the soldering grid line is electrically connected with the emitter. The non-burn-through paste refers to an electrode paste that cannot burn through the passivation layer.

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

[0070] Figure 6 A partial cross-sectional view of a photovoltaic module is provided for an embodiment of the present application.

[0071] In some embodiments, referring to Figure 6 The soldering grid lines 111 include the laminated first sub-grid lines 131 and the second sub-grid lines 132, the second sub-grid lines 132 are located between the connecting components 120 and the first sub-grid lines 131, and the materials of the first sub-grid lines 131 and the second sub-grid lines 132 are different. By setting the laminated first sub-grid lines 131 and the second sub-grid lines 132, the materials of the first sub-grid lines 131 and the second sub-grid lines 132 are different, so that the first sub-grid lines 131 can burn through the passivation layer and be in contact with the doped layer, thereby collecting carriers, so as to have a larger photoelectric conversion efficiency. The second sub-grid lines 132 located above the first sub-grid lines 131 are used for soldering with the connecting components 120, the second sub-grid lines 132 have better compatibility with the connecting components 120 in the molten state, so as to have better soldering quality and higher soldering tension, thereby avoiding the power generation loss problem caused by the separation of the connecting components 120 and the battery piece 100.

[0072] For example, the material of the first sub-grid lines 131 can be silver-aluminum material, and the material of the second sub-grid lines 132 is silver material. For another example, the material of the first sub-grid lines 131 is silver-aluminum material, and the material of the second sub-grid lines 132 is tin paste.

[0073] It should be noted that Figure 6The height of the first sub-gate line 131 in the first sub-gate line 131 and the height of the collecting gate line 112 are consistent only for illustration. In practice, the surface of the first sub-gate line 131 can 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 the height of the first sub-gate line 131 can be higher than the height of the collecting gate line 112.

[0074] Figure 7 Another top view of a soldering gate line in a photovoltaic module provided for an embodiment of the present application; Figure 8 Figure 7 A corresponding sectional view.

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

[0076] In addition, compared with a plurality of soldering gate lines 111, the operable window of the solder pad 113 is larger, thereby reducing the process difficulty of the cell piece, and improving the accuracy and accuracy rate, thereby improving the yield and appearance of the photovoltaic module.

[0077] The connecting component 120 is used to realize the mutual connection between the cell pieces 100 and to converge the current transmission to the elements outside the photovoltaic module. The connecting 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 between the first cell piece and the second cell piece.

[0078] In some embodiments, the connecting component 120 is a core-sheath 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 cell 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 can be plated or coated on the surface of the conductive layer. Specifically, the source material of the solder layer can be uniformly wrapped around the conductive layer in a certain component 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 connecting component 120 satisfy the solderability, and to firmly solder the connecting component 120 on the gate line structure of the cell piece 100, thereby playing a good current conduction role.

[0080] ​In some embodiments, the material of the solder layer is a metal material or an alloy material with a lower melting point than the conductive layer, such as a tin alloy. The tin alloy can include a tin-zinc alloy, a tin-bismuth alloy, or a tin-indium alloy. The soldering of tin as the soldering material has a low melting point and a good affinity with metals such as copper, and has good soldering firmness. The lead in the tin-lead alloy 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 and have good soldering performance and use performance.

[0081] The embodiments disclosed in the present application replace lead with other metal elements or add other elements such as bismuth elements in the tin-lead alloy. The use of bismuth can lower the melting point temperature and reduce the surface tension. The melting point of the tin-bismuth alloy can be lowered to 129°C, meeting the needs of low-temperature soldering. In this way, the stress of the connecting component 120 due to thermal expansion and contraction is small, and the risk and probability of the occurrence of a broken grid of the grid line 111 are reduced.

[0082] In some embodiments, the solder layer has a flux therein. The flux refers to a chemical substance that can help and promote the soldering process in the soldering process, while having a protective effect and preventing oxidation reactions. The flux includes inorganic flux, organic flux, and resin flux. It can be understood that the melting point of the flux is lower than that of the solder layer, and the fluidity of the molten solder layer is increased to form good alloying between the solder layer and the grid line structure.

[0083] In some embodiments, the cross-sectional shape of the connecting component 120 is circular along a cross section perpendicular to the first direction Y. The circular solder strip does not have a directional problem and an alignment problem, and the circular solder strip is easier to mass-produce.

[0084] In some embodiments, the cross-sectional shape of the connecting component 120 can be triangular or any other shape to increase the contact area of the solder strip with the grid line structure and reduce the alignment offset problem of the connecting component 120 and the grid line structure.

[0085] In some embodiments, the surface of the connecting component 120 away from the surface of the battery sheet has a light-reflecting layer. The light-reflecting layer is located on the outer side of the solder layer away from the conductive layer and the battery sheet. The light-reflecting layer is used to improve the electrical loss caused by the shielding area of the connecting component 120 to the battery sheet.

[0086] In some embodiments, the outer surface of the solder layer has a light-reflecting groove. The light-reflecting groove is a concave groove or trench from the solder layer to the conductive layer. The sunlight is reflected to the battery sheet through the sidewall of the light-reflecting groove, improving the utilization rate of sunlight.

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

[0088] In some embodiments, the battery piece includes a first battery piece and a second battery piece. The connecting component 120 connects the first electrode of the first battery piece and the second electrode of the adjacent second battery piece, or the connecting component 120 connects the second electrode of the first battery piece and the first electrode of the adjacent second battery piece. 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, referring to Figure 1 , the front surface of the first battery piece and the front surface of the second battery piece are both directed to the same side, the back surface of the first battery piece and the back surface of the second battery piece are both directed to the same side, or the first electrode of all the battery pieces 100 are directed to the same side, and the second electrode of all the battery pieces 100 are directed to the same side, then the connecting component 120 naturally extends from the front surface of the battery piece to the back surface of the adjacent battery piece, so that the connecting component 120 connects the first electrode and the second electrode of the adjacent battery piece.

[0090] In other embodiments, the first battery piece and the second battery piece are arranged in the order of the first surface, the second surface, the first surface, and the second surface, then the connecting component is not bent, and the connecting component directly connects the first electrode of the first battery piece and the second electrode of the adjacent second battery piece.

[0091] In some embodiments, referring to Figure 1 , there is a battery gap between the adjacent battery pieces 100 to achieve electrical insulation between different battery pieces 100. In other embodiments, there is no battery gap between the adjacent battery pieces, i.e., the battery pieces are arranged in a stacked manner.

[0092] Continuing to refer to Figure 1 , the photovoltaic module further includes a film 11 covering the surface of the battery string and filling the gap between the battery strings. The photovoltaic module further includes a cover plate 12 covering the side of the film 11 away from the battery string.

[0093] The material of the film 11 includes EVA, POE, or PVB, etc. organic encapsulation film.

[0094] In some embodiments, the glass transition temperature of the film 11 is -70 to -10℃, and the glass transition temperature of the film is used to ensure that the film can be in a molten state during the lamination process, to fill the gaps of the photovoltaic module, and to 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 in a molten state, which can effectively prevent the molten adhesive film 11 from penetrating into the solder grid lines 111 and the connecting component 120 and pushing the connecting component 120 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, thereby improving the thermal stress of the battery sheet 100 and improving the yield of the photovoltaic module.

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

[0097] The photovoltaic module provided by the embodiments of the present application has the following advantages. The surface of the battery sheet includes a plurality of grid lines arranged along a second direction and a connecting component 120. The connecting component 120 is welded to each solder grid line 111. The number of solder grid lines 111 is large, that is, the number of welding points between the battery sheet and the connecting component 120 is large, thereby improving the welding tension between the battery sheet and the connecting component 120, avoiding the problem that the connecting component 120 deviates from the battery sheet, and avoiding the problems of EL appearance defects and power generation loss caused by virtual welding. One collecting grid line 112 is electrically connected to a plurality of solder grid lines 111. In this way, the grid lines on the battery sheet can be connected to the connecting component 120 through multiple paths, effectively avoiding the situation of power generation loss caused by broken grid lines.

[0098] Correspondingly, another embodiment of the present application also provides a battery sheet, which is different from the above-mentioned embodiment in that the battery sheet in the above-mentioned embodiment is a non-back contact battery sheet, that is, one side of the battery sheet has grid lines of one conduction type, while the other embodiment of the present application provides a back contact battery sheet, one side of the battery sheet has first grid lines of a first conduction type and second grid lines of a second conduction type. The same or corresponding parts as the above-mentioned embodiment will not be described in detail here.

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

[0100] Another embodiment of the present application provides a photovoltaic module for reducing power generation loss. Referring to Figure 9 and Figure 10The photovoltaic module comprises: a cell sheet 200, the cell sheet 200 comprising a plurality of soldering regions arranged along a first direction X and a plurality of collecting regions.

[0101] In some embodiments, the cell sheet 200 is a back contact cell sheet, for example, an Interdigitated back contact (IBC) cell. The 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 back surface of the cell. The PN junction and the electrodes are located on the back surface of the cell, i.e., the electrodes of the emitter region and the base region of the IBC cell are located on the back surface, and there is no grid line on the front surface to block the light, which can improve the photoelectric conversion performance of the cell.

[0102] With reference to Figure 10 The soldering regions can comprise a first soldering region 2011 and a second soldering region 2012, and the collecting regions can comprise a first collecting region 2021 and a second collecting region 2022.

[0103] The surface of the cell sheet 200 has a plurality of grid lines arranged along a second direction, each grid line comprising at least two soldering grid lines located in the soldering regions and a collecting grid line located in the collecting regions, wherein the soldering grid lines are arranged along the second direction, and each soldering grid line of the at least two soldering grid lines is electrically connected to the same collecting grid line.

[0104] In some embodiments, with reference to Figure 10 The grid lines comprise a first grid line 240 of a first conductive type and a second grid line 250 of a second conductive type, the first grid line 240 comprises a first soldering grid line 241 corresponding to the first soldering region 2011 and a first collecting grid line 242 corresponding to the first collecting region, the second grid line 250 comprises a second soldering grid line 251 corresponding to the second soldering region 2012 and a second collecting grid line 252 corresponding to the second collecting region 2022, the first soldering region 2011 and the second collecting region 2022 are directly opposite along the second direction Y, and the second soldering region 2012 and the first collecting region 2021 are directly opposite along the second direction Y.

[0105] With reference to Figure 10 The photovoltaic module comprises: a connecting component located on the cell sheet. The connecting component comprises 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 soldered to each first soldering grid line 241; and 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 soldered to each second soldering grid line 251.

[0106] With reference to Figure 10The photovoltaic module further comprises an insulation layer 260 between the first connecting component 221 and the second collecting busbar 252. The insulation layer 260 is also between the second connecting component 222 and the first collecting busbar 242.

[0107] In some embodiments, the insulation layer 260 is an independent glue block corresponding to the first connecting component 221 and the second collecting busbar 252, and the second connecting component 222 and the first collecting busbar 242, so as to reduce the use amount of the insulation layer 260 and the manufacturing cost.

[0108] The size, length and thickness of the insulation layer 260 are not limited in the embodiments of the present application, as long as the insulation layer 260 can insulate the first connecting component 221 and the second collecting busbar 252, and the second connecting component 222 and the first collecting busbar 242.

[0109] In some embodiments, the insulation layer 260 not only covers the first soldering area 2011, but also extends to the first collecting area 2021 with a width of 0.5mm-2.5mm, so as to reduce the difficulty of series connection and effectively avoid the risk of short circuit.

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

[0111] Similarly, the insulation layer 260 not only covers the second soldering area 2012, but also extends to the second collecting area 2022 with a width of 0.5mm-2.5mm.

[0112] Figure 11 Another top view of a photovoltaic module according to another embodiment of the present application is provided; Figure 12 Another partial cross-sectional view of the photovoltaic module according to the embodiment of the present application is provided. Figure 11 Another partial cross-sectional view of the photovoltaic module according to the embodiment of the present application is provided. Figure 13 Another partial cross-sectional view of the photovoltaic module according to the embodiment of the present application is provided. Figure 11 Another partial cross-sectional view of the photovoltaic module according to the embodiment of the present application is provided.

[0113] In some embodiments, the insulation layer 260 not only covers the first soldering area 2011, but also extends to the first collecting area 2021 with a width of 0.5mm-2.5mm, so as to reduce the difficulty of series connection and effectively avoid the risk of short circuit. Figure 11The insulating layer 260 is located on the first gate line 240 and the second gate line 250, and has a hollow area 261 corresponding to the first soldering area 2011, which exposes the first soldering gate line 241. The hollow area also corresponds to the second soldering area 2012, which exposes the second soldering gate line 251. In this way, the entire insulating layer 260 is provided, and the hollow area 261 is provided in the corresponding area to achieve electrical connection between the first connecting component 221 and the first soldering gate line 241 and between the second connecting component 222 and the second soldering gate line 251, thereby reducing the difficulty of printing insulating layer blocks one by one and the alignment requirement, and thus reducing the process difficulty.

[0114] In some embodiments, the insulating layer 260 covers the first soldering area 2011 and further extends to a partial width of the first collecting area 2021 beyond the first soldering area 2011, and the extension to the first collecting area 2021 has a width of 0.5mm-2.5mm; and another insulating layer 260 covers the second soldering area 2012 and further extends to a partial width of the second collecting area 2022 beyond the second soldering area 2012, and the extension to the second collecting area 2022 has a width of 0.5mm-2.5mm. In this way, the difficulty of series soldering is reduced, and the risk of short circuit is effectively avoided.

[0115] In some embodiments, at least two first soldering gate lines 241 of the same first gate line 240 are in contact with each other to form a solder pad, and the width of the solder pad along the second direction is greater than the width of the first collecting gate line 242 along the second direction Y. In this way, the solder pad and the connecting component are used to achieve electrical connection. Compared with a single gate line, the width of the solder pad is larger, thereby avoiding the problem of broken gate line and the problem of insufficient soldering tension, and thus improving the soldering quality. In addition, compared with a plurality of soldering gate lines, the operable window of the solder pad is larger, thereby reducing the process difficulty of the battery piece and improving the accuracy and accuracy rate, and thus improving the yield and aesthetic appearance of the photovoltaic module.

[0116] Similarly, in some embodiments, at least two second soldering gate lines 251 of the same second gate line 250 are in contact with each other to form a solder pad, and the width of the solder 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, referring to Figure 13 Corresponding to the area of the connecting component, the top surface of the first soldering gate line 241 close to the insulating layer 260 is higher than the top surface of the first soldering gate line 241 away from the insulating layer 260, i.e., the height h1 of the first soldering gate line 241 close to the insulating layer 260 can be greater than the height h2 of the first soldering gate line 241 away from the insulating layer 260. From the perspective of the soldering process, the soldering process is easier when the soldering area is higher, and the soldering quality is better. Figure 12 and Figure 13As can be seen, the height h1 of the first solder grid line 241 close to the insulating layer 260 is slightly higher, so that the contact area between the first connecting component 221 and the top surface of the first solder grid line 241 close to the insulating layer 260 is increased, so as to improve the soldering quality and increase the soldering tension.

[0118] In some embodiments, the width of the first solder grid line 241 close to the insulating layer 260 can be greater than the width of the first solder grid line 241 away from the insulating layer 260.

[0119] In some embodiments, the distance between the insulating layer 260 and the first solder grid line 241 is proportional to the thickness of the insulating layer 260, that is, the greater the thickness of the insulating layer 260, the greater the distance between the insulating layer 260 and the first solder grid line 241, and the greater the area opened by the hollowed-out area, so that the first connecting component 221 has a larger space to deform and the contact area between the connecting component and the first solder grid line 241 is larger. Conversely, the smaller the thickness of the insulating layer 260, the smaller the distance between the insulating layer 260 and the first solder grid line 241, and the smaller the area opened by the hollowed-out area.

[0120] In some embodiments, the thickness of the insulating layer 260 decreases along the second direction Y and in the direction towards the first solder grid line 241. In this way, the first connecting component 221 can be soldered with the first solder grid line 241 along the change trend of the thickness of the insulating layer 260, so as to increase the soldering area and avoid the problem of false soldering.

[0121] Figure 14 A partial top view of a photovoltaic module according to another embodiment of the present application is provided.

[0122] In some embodiments, the first collecting grid line 242 includes two first broken grid lines 206 and a first broken gap 205 between the two first broken grid lines 206, the first broken gap 205 corresponds to the second soldering area 2012, and the first broken grid lines 206 are located on both sides of the second connecting component and are insulated from the second connecting component.

[0123] The second collecting grid line 252 includes two broken grid lines 204 and a broken gap 203 between the two broken grid lines 204, the broken gap 203 corresponds to the first soldering area 2011, and the broken grid lines 204 are located on both sides of the first connecting component and are insulated from the first connecting component.

[0124] In some embodiments, continuing to refer to Figure 9 The photovoltaic module further includes a cell string, the cell string is composed of a plurality of cell pieces in the above-mentioned embodiments through connecting components, wherein the connecting components are used to connect adjacent cell pieces in series.

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

[0126] With continued reference to Figure 9 The photovoltaic module further includes a film 21 covering the surface of the battery string and filling the gap between the battery strings. The photovoltaic module further includes a cover plate 22 covering the side of the film 21 away from the battery string.

[0127] The photovoltaic module provided by the embodiments of the present application has the following advantages. The surface of the battery piece includes a plurality of first busbar lines 240 arranged along the second direction, the first busbar line 240, the first connecting component 221 and the second connecting component 222. The first connecting component 221 is welded to each first soldered busbar line 241, and the second connecting component 222 is electrically connected to the second soldered busbar line 251. The first soldered busbar line 241 and the first connecting component 221 are electrically connected, and the second soldered busbar line 251 and the second connecting component 222 are welded. The number of the first soldered busbar line 241 and the second soldered busbar line 251 is large, i.e., the number of the welding points between the battery piece and the first connecting component 221 and the number of the second connecting component 222 are large. Thus, the welding tension between the battery piece and the connecting component can be improved, the problem that the connecting component is separated from the battery piece can be avoided, and the problems of EL appearance defect and power generation loss caused by virtual welding can be avoided. One first collecting busbar line 242 is electrically connected to a plurality of first soldered busbar lines 241. In this way, the first busbar line on the battery piece can be connected to the first connecting component 221 through a plurality of paths, and the situation of power generation loss caused by broken busbar can be effectively avoided.

[0128] Those skilled in the art can understand that the above-mentioned embodiments are specific embodiments for implementing the present application, and in actual application, various changes can be made in form and details without departing from the spirit and scope of the present application. Any person skilled in the art can make various modifications and changes without departing from the spirit and scope of the present application, and therefore the protection scope of the present application should be limited by the scope defined in the claims.

Claims

1. A photovoltaic module, characterized by, The battery piece comprises welding areas and collecting areas arranged along a first direction. The surface of the battery piece has a plurality of grid lines arranged along a second direction, each of the grid lines comprises at least two welding grid lines located at the welding areas and a collecting grid line located at the collecting area, 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 piece, 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. The battery piece is a back contact battery piece, the grid lines comprise first grid lines of a first conductive type and second grid lines of a second conductive type, the first grid lines comprise first welding grid lines corresponding to first welding areas and first collecting grid lines corresponding to first collecting areas, the second grid lines comprise second welding grid lines corresponding to second welding areas and second collecting grid lines corresponding to second collecting areas, the first welding areas face the second collecting areas along the second direction, and the second welding areas face the first collecting areas along the second direction; and the battery piece further comprises an insulating layer located between the connecting component and the second collecting grid line. The insulating layer is located on the first grid lines and the second grid lines, and exposes the first welding grid lines in regions corresponding to the first welding areas. The distance between the insulating layer and the first welding grid lines is proportional to the thickness of the insulating layer. The width of the welding grid lines along the second direction is greater than or equal to the width of the collecting grid lines along the second direction.

2. The photovoltaic module of claim 1, wherein, The welding grid lines comprise first type grid lines and second type grid lines, the first type grid lines and the collecting grid lines are composed of burn-through paste, and the second type grid lines are composed of non-burn-through paste.

3. The photovoltaic module of claim 1, wherein, The welding grid lines comprise 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 materials of the first sub-grid line and the second sub-grid line are different.

4. The photovoltaic module according to claim 1 or 3, characterized in that At least two first welding grid lines of the same first grid line are in contact with each other to form a bonding pad, and the width of the bonding pad along the second direction is greater than the width of the first collecting grid line along the second direction.

5. The photovoltaic module of claim 1, wherein, The top surface of the first welding grid line close to the insulating layer is higher than the top surface of the first welding grid line away from the insulating layer in a region corresponding to the connecting component.

6. The photovoltaic module of claim 1, wherein, The thickness of the insulating layer decreases in the direction along the second direction and towards the first welding grid line.

7. The photovoltaic module of claim 1, wherein, The second collecting grid line comprises two broken grid lines and a break located between the two broken grid lines, the break corresponds to the first welding area, the broken grid lines are located on both sides of the connecting component and are insulated from the connecting component.

8. The photovoltaic module of claim 1, wherein, ​

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