Photovoltaic module

Abstract

The invention provides a photovoltaic module, and relates to the technical field of photovoltaics. The photovoltaic module comprises an interconnection piece and a plurality of battery pieces. The battery piece comprises a current collection electrode which is arranged on the side, away from the doped conductive layer, of the passivation layer, the current collection electrode comprises a transmission part and a plurality of contact parts, and interval areas exist between the adjacent contact parts in the first direction; the transmission part is arranged on one side, far away from the semiconductor substrate, of the contact part and is in contact connection with the plurality of contact parts; the plurality of interconnection parts are electrically connected with the current collection electrodes; along the second direction, the plurality of interconnection parts are arranged in rows to form interconnection part rows; in the battery piece, the areas located in the two opposite boundaries of the interconnection part columns in the first direction are confluence areas, and at least one confluence area is provided with at least one part of at least one contact part and a partial transmission part. The pulling force of the current collection electrode and the semiconductor substrate can be enhanced, falling or pulling-off is avoided, and meanwhile collection and transmission of current are facilitated.

Description

Technical Field

[0001] The present invention relates to the field of photovoltaic technology, in particular to a photovoltaic module. Background Art

[0002] Photovoltaic modules are typically composed primarily of cells and interconnects. Cells primarily consist of a semiconductor substrate, a doped conductive layer, a passivation layer, and a collector electrode. The collector electrode is primarily responsible for collecting photogenerated carriers and transmitting current. The collector electrode typically includes a transmission section, which is located between the semiconductor substrate and the interconnect.

[0003] In existing photovoltaic modules, the bonding strength between the interconnection parts and the transmission parts and substrate is usually difficult to ensure effectively, which usually leads to separation of the transmission parts and the semiconductor substrate, seriously affecting the yield and reliability of the product. Summary of the Invention

[0004] The present invention provides a photovoltaic module, aiming to solve the problem of separation between a transmission part and a semiconductor substrate in existing photovoltaic modules.

[0005] A first aspect of the present invention provides a photovoltaic module, comprising: an interconnection element and a plurality of solar cells; The cell comprises: a semiconductor substrate; a doped conductive layer disposed on the semiconductor substrate; and a passivation layer disposed on a side of the doped conductive layer away from the semiconductor substrate. A plurality of collector electrodes are arranged on a side of the passivation layer away from the doped conductive layer, the plurality of collector electrodes extend along a first direction and are spaced apart along a second direction; the collector electrodes are divided into a first collector electrode and a second collector electrode with different polarities, the first collector electrode and the second collector electrode are located on the same side of the semiconductor substrate, or on opposite sides; the first collector electrode and / or the second collector electrode include: a transmission portion and a plurality of contact portions, the plurality of contact portions passing through the passivation layer and electrically connected to the doped conductive layer, and a spacing region exists between the contact portions adjacent to each other along the first direction; the transmission portion is arranged on a side of the contact portion away from the semiconductor substrate, and is in contact with and connected to the plurality of contact portions; a plurality of interconnects electrically connected to the collector electrode; the plurality of interconnects are arranged in a row along the second direction to form an interconnection row; in the battery cell, regions within two opposite boundaries of the interconnection row along the first direction are confluence regions, and at least one of the confluence regions is provided with at least a portion of at least one of the contact portions and a portion of the transmission portion; The interconnection member is electrically connected to the collector electrode of the battery cell through the interconnection portion; the extension direction of the interconnection member is parallel to the extension direction of the busbar area and covers at least a portion of the busbar area.

[0006] In the present application, in the battery cell, the area within the two opposite boundaries of the interconnection column along the first direction is the convergence area, the interconnection component covers at least part of the convergence area, and at least one convergence area is provided with at least a part of at least one contact part and part of the transmission part, that is, not only the transmission part but also the contact part is provided in the area where the interconnection column is located, and the contact part is electrically connected to the doped conductive layer through the passivation layer, that is, the bonding force between the contact part and the doped conductive layer is stronger, and the contact part enhances the bonding force between the transmission part and the semiconductor substrate, which can enhance the tension between the collector electrode and the semiconductor substrate after the interconnection part is electrically connected to the transmission part through the interconnection component, thereby avoiding falling off or pulling off, and improving the yield and reliability of the photovoltaic module.

[0007] In some possible embodiments, the battery cell further includes: a plurality of bus electrodes electrically connected to the collecting electrodes, and the interconnection portion electrically connected to the bus electrodes; and at least a portion of at least one of the contact portions is provided within the horizontal projection area of ​​at least one bus electrode.

[0008] After the interconnection part is electrically connected to the transmission part through the interconnection piece, the pulling force between the collector electrode and the semiconductor substrate can be enhanced, thereby avoiding falling off or pulling off, and facilitating current collection and transmission.

[0009] In some possible embodiments, the extending direction of the transmission portion and the contact portion is the same as the extending direction of the collecting electrode.

[0010] Since the carriers need to be collected by the contact part, transferred to the transmission part and then pass through the interconnection part and the interconnection component to realize current collection, the extension direction of the contact part, the transmission part and the collector electrode are the same / parallel, which can increase the contact area between the contact part and the transmission part, increase the carrier transmission channel, reduce the transmission dead zone, and improve the current collection and transmission effect.

[0011] In some possible embodiments, along the second direction, at least two contact portions are provided in at least one interconnection portion column at least two of which are spaced apart from each other; and / or, Along the first direction, at least two contact portions are provided in at least one interconnection portion column and are spaced apart from each other.

[0012] In some possible embodiments, the sum of the areas of the contact portions in at least one of the interconnection portion columns is greater than the sum of the areas of the contact portions in the remaining interconnection portion columns; and / or, The sum of the lengths of the contact portions in at least one of the interconnection portion columns along the first direction is greater than the sum of the lengths of the contact portions in the remaining interconnection portion columns along the first direction; and / or, The number of the contact portions in at least one of the interconnection portion columns is greater than the number of the contact portions in the remaining interconnection portion columns.

[0013] In some possible embodiments, at least a portion of at least one contact portion is disposed within a horizontal projection area of ​​at least one interconnection portion.

[0014] In some possible embodiments, along the first direction, a ratio of a length of the contact portion in a horizontal projection area of ​​an interconnection portion to a length of the interconnection portion is 50%-100%.

[0015] In some possible embodiments, the interconnection portion includes: a large interconnection portion and a small interconnection portion, and along the first direction: the maximum dimension of the large interconnection portion is larger than the maximum dimension of the small interconnection portion, and / or, along the second direction: the maximum dimension of the large interconnection portion is larger than the maximum dimension of the small interconnection portion; The sum of the areas of the contact portions provided within the horizontal projection area of ​​at least one of the large interconnections is greater than or equal to the sum of the areas of the contact portions provided within the horizontal projection area of ​​the small interconnections; and / or The sum of the lengths of the contact portions arranged in the horizontal projection area of ​​the large interconnection along the first direction is greater than or equal to the sum of the lengths of the contact portions arranged in the horizontal projection area of ​​the small interconnection along the first direction; and / or The number of the contact portions provided within the horizontal projection area of ​​the large interconnection is greater than or equal to the number of the contact portions provided within the horizontal projection area of ​​the small interconnection.

[0016] More contacts can disperse the stress of large interconnects, further increase the pulling force, and improve the current collection capacity of a single large interconnect.

[0017] In some possible embodiments, within the same area: the sum of the lengths of the contact portions arranged in the horizontal projection area of ​​at least one of the interconnection portions along the first direction is greater than the sum of the lengths of the contact portions arranged in the non-interconnection portion area along the first direction; and / or In the same area: the sum of the areas of the contact portions provided in the horizontal projection area of ​​at least one of the interconnected portions is greater than the sum of the areas of the contact portions provided in the non-interconnected portion area; and / or In the same area: the number of the contact portions provided in the horizontal projection area of ​​at least one of the interconnected portions is greater than the number of the contact portions provided in the non-interconnected portion area; and / or Within the same area: the ratio of the length of the contact portion provided in the horizontal projection area of ​​at least one of the interconnected portions along the first direction to the length of the spacing area adjacent to the contact portion along the first direction is greater than the ratio of the length of the contact portion provided in the non-interconnected portion area along the first direction to the length of the spacing area adjacent to the contact portion along the first direction.

[0018] In some possible embodiments, at least two rows of contact portions are provided within a horizontal projection area of ​​at least one of the interconnection portions.

[0019] In some possible embodiments, the sum of the lengths of the contact portions provided in a row of the contact portions within the horizontal projection area of ​​the interconnection portion along the first direction is greater than the sum of the lengths of the contact portions provided in an adjacent row of the contact portions along the first direction; and / or, The sum of the areas of the contact portions provided in a row of the contact portions within the horizontal projection area of ​​the interconnection portion is greater than the sum of the areas of the contact portions provided in the non-interconnection portion area; and / or The number of the contact portions provided in one row of the contact portions within the horizontal projection area of ​​the interconnection portion is greater than the number of the contact portions provided in an adjacent row of the contact portions; and / or, The ratio of the length of the contact portion arranged in a row of the contact portions within the horizontal projection area of ​​the interconnection portion along the first direction to the length of the spacing region adjacent to the contact portion along the first direction is greater than the ratio of the length of the contact portion arranged in an adjacent row of the contact portions along the first direction to the length of the spacing region adjacent to the contact portion along the first direction.

[0020] In some possible embodiments, the first collecting electrode includes: a first transmission portion and a plurality of first contact portions arranged at intervals, and the second collecting electrode includes: a second transmission portion and a plurality of second contact portions arranged at intervals; in at least one of the first collecting electrodes, the ratio of the length of a first contact portion along the first direction to the length of the spacing region adjacent to the first contact portion along the first direction is greater than the ratio of the length of a second contact portion along the first direction to the length of the spacing region adjacent to the second contact portion along the first direction in at least one of the second collecting electrodes.

[0021] In some possible embodiments, the first collecting electrode includes: a first transmission portion and a plurality of first contact portions disposed at intervals; the second collecting electrode includes: a second transmission portion and a plurality of second contact portions disposed at intervals; and in at least one of the first collecting electrodes, a length of at least one of the first contact portions along the first direction is greater than a length of at least one of the second contact portions along the first direction in at least one of the second collecting electrodes. Alternatively, the first collecting electrode includes: a first transmission portion and a continuously arranged first contact portion, and the second collecting electrode includes: a second transmission portion and a plurality of spaced second contact portions, and the length of the first contact portion along the first direction is greater than the length of the second contact portion along the first direction.

[0022] In some possible embodiments, the first collecting electrode includes: a first transmission portion and a plurality of first contact portions spaced apart; the second collecting electrode includes: a second transmission portion and a plurality of second contact portions spaced apart; in at least one of the first collecting electrodes, a ratio of a length of one of the first contact portions along the first direction to a length of the spaced region adjacent to the first contact portion along the first direction is 0.5-10; and / or, In at least one of the second collecting electrodes, a ratio of a length of one of the second contact portions along the first direction to a length of the spacing region adjacent to the second contact portion along the first direction is 0.5-10.

[0023] Generally speaking, for crystalline silicon solar cells, the first doped conductive layer has a lower doping concentration and poorer conductivity than the second doped conductive layer. Therefore, by setting the first contact portion in the first collecting electrode electrically connected to the first doped semiconductor to be longer, it is more conducive to taking into account the carrier collection balance of the two conductive areas, and the electrical performance of the photovoltaic module can be further improved.

[0024] In some possible embodiments, in some possible embodiments, the first collecting electrode includes: a first transmission portion and a plurality of first contact portions arranged at intervals, and the second collecting electrode includes: a second transmission portion and a plurality of second contact portions arranged at intervals; in the first direction, in at least one of the first collecting electrodes, the spacing between at least one pair of adjacent first contact portions is smaller than the spacing between at least one pair of adjacent second contact portions in at least one of the second collecting electrodes.

[0025] In some possible embodiments, the height of the contact portion is h1, the height of the transmission portion is h2, and 0.08≤h1 / h2≤0.8.

[0026] 0.08≤h1 / h2≤0.8, that is, the ratio of the height of the contact part to the height of the transmission part h1 / h2 is within a reasonable range. It is the result of comprehensive consideration of the shading problem of the transmission part and the contact part, the metal contact effect, and the ability to transmit carriers. It ensures the current transmission efficiency while being beneficial to the welding effect of the welding strip and ensuring the product yield.

[0027] In some possible embodiments, along the second direction, the width of the contact portion is W1, the width of the transmission portion is W2, and 0.04≤W1 / W2≤0.5.

[0028] To ensure that the contact area between the contact portion and the transmission portion is within a reasonable range, the current transmission efficiency is improved, while the process difficulty of forming the contact portion is reduced and the processing efficiency is improved.

[0029] In some possible embodiments, the interconnection portion column includes interconnections of at least two sizes along the first direction.

[0030] In some possible embodiments, the number of the contact portions provided in one confluence area is 2 to 1500; and / or, The number of the contact portions within a horizontal projection area of ​​one interconnection portion is 0 to 600.

[0031] In some possible embodiments, in at least one of the confluence areas along the first direction: the ratio of the total length of the contact portion to the total length of the spacing area is c; in the area outside the confluence area along the first direction: the ratio of the total length of the contact portion to the total length of the spacing area is d, 30≥c / d>1.

[0032] 30≥c / d>1 is the optimal choice considering the binding force, current collection capability, and cost.

[0033] In some possible embodiments, along the first direction: the length of the spacing region is M1, the length of the contact portion is M2, and the width of the interconnection member is W3; 0.001W3≤M1≤3×W3; and / or, 0.01W3≤M2≤5×W3.

[0034] In some possible embodiments, the length of the spacer region is M1, the length of the contact portion is M2, and the length of the interconnection portion is W4; 0.001×W4≤M1≤2.5×W4; and / or, 0.01×W4≤M2≤3×W4.

[0035] In some possible embodiments, in an area corresponding to a battery cell: the number of busbar areas where at least one contact portion and a portion of a transmission portion are provided accounts for 50% to 100% of the number of busbar areas in the area corresponding to the battery cell; and / or, The sum of the areas of the contact portion away from the surface of the semiconductor substrate within the horizontal projection region of the interconnection portion is S1, the area of ​​the interconnection portion close to the semiconductor substrate is S2, and the ratio of S2 to S1 is greater than 1 and less than or equal to 200.

[0036] This application not only has low cost, less shading, and better passivation effect, but also has a better effect on improving the pulling force and current collection capacity.

[0037] In some possible embodiments, the photovoltaic assembly further includes: a bonding material layer located at a bonding position between the interconnection portion and the interconnection member; At least one contact portion is provided within a horizontal projection area of ​​at least a portion of the bonding material layer.

[0038] In some possible embodiments, at least one of the transmission parts and at least one of the interconnection parts are integrally formed.

[0039] In some possible embodiments, the material of the contact portion is selected from at least one of nickel, silver, aluminum, zinc, iron, cobalt, magnesium, gold, and palladium; and / or, The material of the transmission part is selected from base metals.

[0040] In some possible embodiments, along the first direction: the length of the spacing area is M1, the length of the contact portion is M2, M1 is 0.2 mm to 1.5 mm, and M2 is 0.3 mm to 3 mm.

[0041] In some possible embodiments, the contact portion is made of a burn-through paste, and a portion of the transmission portion is embedded in a recessed portion of the contact portion. The contact portion burns through a portion of the passivation layer to establish ohmic contact with the doped conductive layer, and the contact with the doped conductive layer is further strengthened after the medium or high temperature burn-through.

[0042] In some possible embodiments, an organic substance is disposed at at least a partial interface position between the contact portion and the transmission portion, and the organic substance isolates the contact portion from the transmission portion; and / or The transmission part has a plurality of metal particles on the side close to the contact part. The metal particles are filled in holes or depressions on the surface of the contact part. Organic matter is arranged between the metal particles in the holes or depressions and the walls of the holes or depressions.

[0043] In some possible embodiments, the thickness of the organic matter is 0.01 nm to 50 nm.

[0044] In some possible embodiments, the cell is at least one of a back contact cell, a heterojunction HJT cell, a TOPCon cell, and a stacked photovoltaic cell, wherein the bottom cell of the stacked photovoltaic cell is at least one of a back contact cell, a heterojunction HJT cell, and a TOPCon cell, and the top cell is a perovskite cell.

[0045] A second aspect of the present invention provides a photovoltaic system comprising: a plurality of any of the aforementioned photovoltaic modules; in the photovoltaic system, the photovoltaic modules are arranged in an array. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0047] Figure 1 、 Figure 4 、 Figure 5 and Figure 6 A schematic diagram of a partial bottom-up structure of a photovoltaic assembly in an embodiment of the present invention is shown; Figure 2 and Figure 3 Two schematic cross-sectional structures of photovoltaic modules in embodiments of the present invention are shown; Figure 7 Showing various structural schematic diagrams of the interconnection portion of the photovoltaic module in the embodiment of the present invention; Figures 8 to 10 Schematic diagrams of several matching structures of the interconnection part and the contact part of the photovoltaic module in the embodiment of the present invention are shown.

[0048] Description of the accompanying figures: 1-interconnection, 21-semiconductor substrate, 221-first doped conductive layer, 222-second doped conductive layer, 23-passivation layer, 24-collecting electrode, 241-first collecting electrode, 2411-first contact portion, 2412-first transmission portion, 242-second collecting electrode, 2421-second contact portion, 2422-second transmission portion, 25-interconnection portion, 251-large interconnection portion, 252-small interconnection portion, 26-terminal line, 27-interface passivation transmission layer. DETAILED DESCRIPTION

[0049] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0050] The present invention provides a photovoltaic module, referring to Figure 1 The photovoltaic module includes: an interconnection element 1 and a plurality of solar cells. Figures 2 to 3 The cell includes: a semiconductor substrate 21; a doped conductive layer disposed on the semiconductor substrate 21; a passivation layer 23 disposed on a side of the doped conductive layer away from the semiconductor substrate 21; and multiple collector electrodes 24 disposed on a side of the passivation layer 23 away from the doped conductive layer. The doped conductive layers may include: a first doped conductive layer 221 and a second doped conductive layer 222. The semiconductor substrate 21 may comprise a silicon substrate, either N-type single crystal silicon or P-type single crystal silicon, which can provide long-life carriers. Of the first doped conductive layer 221 and the second doped conductive layer 222, one is a P-type doped conductive layer, and the other is an N-type doped conductive layer. The P-type doped conductive layer may contain one or more elements from Group IIIA (for example, boron). The N-type doped conductive layer may contain one or more elements from Group VA (for example, phosphorus). The materials of the N-type and P-type doped conductive layers may include any semiconductor material, such as silicon, silicon germanium, germanium, or gallium arsenide. In terms of the material arrangement, the crystalline phase of the doped conductive layer can be amorphous, microcrystalline, nanocrystalline, single crystal, or polycrystalline. The materials of the N-type doped conductive layer and the P-type doped conductive layer can be the same or different. For example, the materials of both the N-type doped conductive layer and the P-type doped conductive layer can be doped polycrystalline silicon. Another example is that the material of the P-type doped conductive layer can be doped polycrystalline silicon, while the material of the N-type doped conductive layer can include at least one of doped amorphous silicon, doped microcrystalline silicon, and doped nanocrystalline silicon. Another example is that the material of the P-type doped conductive layer can be doped single crystal silicon, i.e., formed by diffusion on the surface of the P region of the silicon substrate, while the material of the N-type doped conductive layer can be doped polycrystalline silicon. The P-type doped conductive layer can be prepared by in-situ doping or ex-situ doping. The N-type doped conductive layer can also be prepared by in-situ doping or ex-situ doping. The passivation layer 23 primarily refers to a surface passivation layer, which can provide passivation and anti-reflection effects, and can be a silicon nitride layer, aluminum oxide, etc. The interconnects herein can include solder ribbons, conductive backplanes, etc. The interconnect portion can be an electrode pad, such as a solder pad. It should be noted that Figure 2 The interface passivation transport layer 27 disposed adjacent to the semiconductor substrate 21 can provide both good interface passivation and carrier selective transport, and its specific material is not limited. For example, the interface passivation transport layer 27 can be a tunneling oxide layer.

[0051] The collector electrode 24 here may include: at least one of a first collector electrode 241 and a second collector electrode 242. A plurality of collector electrodes 24 extend along the first direction L1 and are spaced apart along the second direction L2. The collector electrode 24 includes a transmission portion and a plurality of contact portions, and the plurality of contact portions are electrically connected to the doped conductive layer through the passivation layer 23, which may refer to: the first collector electrode 241 includes: a first transmission portion 2412 and a plurality of first contact portions 2411, and / or, the second collector electrode 242 includes: a second transmission portion 2422 and a plurality of second contact portions 2421. In other words, the contact portions in the collector grid lines of only one polarity may be intermittently arranged, or the contact portions in the collector grid lines of different polarities may be intermittently arranged. For example, Figures 1 to 3 In the embodiment, the first collecting electrode 241 includes a first transmission portion 2412 and a plurality of first contact portions 2411 , and the second collecting electrode 242 includes a second transmission portion 2422 and a plurality of second contact portions 2421 .

[0052] The presence of a spacing region between adjacent contact portions along the first direction L1 means that the contact portions located within the same collector electrode along the first direction L1 are intermittently arranged. Specifically, this means that a spacing region exists between adjacent first contact portions 2411 along the first direction L1, and / or a spacing region exists between adjacent second contact portions 2421 along the first direction L1. The transmission portion is disposed on a side of the contact portion away from the semiconductor substrate and is in contact and connected with multiple contact portions. The transmission portion extends along the first direction. Specifically, the first transmission portion 2412 is disposed on a side of the first contact portion 2411 away from the semiconductor substrate 21 and is in contact and connected with multiple first contact portions 2411. The first transmission portion 2412 extends along the first direction L1. The second transmission portion 2422 is disposed on a side of the second contact portion 2421 away from the semiconductor substrate 21 and is in contact and connected with multiple second contact portions 2421. The second transmission portion 2422 extends along the first direction L1.

[0053] The cell also includes: a plurality of interconnecting portions 25 electrically connected to the collector electrodes 24. The interconnecting portions 25 here can be provided separately, for example, printed, or can be thickened sections of the collector grid lines. Figure 7 , Figure 7 (a) to (e) are five structural schematic diagrams of the interconnection portion 25. Figure 7 The interconnection portion 25 shown in (a) is in the shape of a rectangular parallelepiped structure. Figure 7 The interconnection portion 25 shown in (a) may be provided separately. Figure 7 The interconnection portion 25 shown in (b) to (e) may be provided separately or may be a thickened section of the collector electrode 24. For example, Figure 7In the interconnection portion 25 shown in (c) to (e), the main portion along the first direction L1 is provided separately, and the extension portion connected to the main portion and protruding from the main portion along the first direction L1 can be a thickened section of the collecting electrode 24 . Figure 7 The interconnection portion 25 shown in (b) is in the shape of an ellipsoid. Figure 7 The main body of the interconnection portion 25 shown in (c) is ellipsoidal, and the extended portion is conical. Figure 7 The main body of the interconnection portion 25 shown in (d) is in the shape of a rectangular parallelepiped, and the extended portion is in the shape of a rectangular parallelepiped. Figure 7 The main body of the interconnection portion 25 shown in (e) is in the shape of a rectangular parallelepiped, and the extended portion is in the shape of a cone. Figure 7 (a) to (e) are five structural schematic diagrams of the interconnection portion 25, which are usually located in different battery cells. However, it is not excluded that at least two structures of the interconnection portion 25 are located in the same battery cell, which all fall within the scope of protection of this application.

[0054] The relative positions of the interconnection 25 and the collector electrode 24 can be determined according to the preparation sequence. For example, one preparation sequence may be: first set the interconnection 25, and then set the collector electrode 24, so the interconnection 25 is located on the side of the collector electrode 24 close to the semiconductor substrate 21. For another example, another preparation sequence is to first set the collector electrode 24, and then set the interconnection 25, so the interconnection 25 is located on the side of the collector electrode 24 away from the semiconductor substrate 21. That is, the side of the first collector electrode 241 away from the semiconductor substrate 21, and the side of the second collector electrode 242 away from the semiconductor substrate 21 both have multiple interconnections 25. Along the second direction L2, the multiple interconnections 25 are arranged in a column to form an interconnection column, for example, Figure 1 In the embodiment, there are two interconnection columns, the interconnection columns extend along the second direction L2, and all interconnections in one interconnection column are electrically connected to the collector electrodes of the same polarity. Figure 1 , the interconnection columns on the left are all electrically connected to the first collecting electrode 241, and the interconnection columns on the right are all electrically connected to the second collecting electrode 242. It should be noted that, in order to avoid short circuits, insulating glue or the like may be provided at the position where the interconnection contacts or overlaps with the collecting electrode of the other polarity. In the battery cell, the area within the two opposite boundaries of the interconnection column along the first direction L1 is the convergence area, that is, one interconnection column corresponds to one convergence area, and in the first direction L1, the boundary of the convergence area corresponding to one interconnection column coincides with the outermost boundary of the interconnection column in the first direction L1, or with the inner boundary of the interconnection column. For example, Figure 1 In the figure, the area between the dotted lines on the left and right sides of the interconnection column on the left is a schematic representation of a confluence area. Figure 7In (a) to (e), the area between the dotted lines on the left and right sides of each interconnection 25 is a partial schematic diagram of the confluence area. Figure 8 In the figure, the area between the dotted lines on the left and right sides of the interconnection column is a partial schematic diagram of the confluence area. At least one confluence area is provided with at least a portion of at least one contact portion and a portion of the transmission portion. It should be noted that, in addition to the positions of the various interconnections in the interconnection column, the confluence area also includes the area between the adjacent interconnections in the second direction L2 in the interconnection area. The area between the adjacent interconnections in the second direction L2 in the confluence area is provided with at least a portion of at least one contact portion and a portion of the transmission portion, which also falls within the scope of protection of the present application. The confluence area provided with at least a portion of at least one contact portion here means: with reference to Figure 8 In the confluence area ( Figure 8 (a) where the interconnection portion 25 is located) is provided with at least one complete contact portion, and / or, a confluence area ( Figure 8 (b) a location where the interconnection portion 25 is located) is provided with a partial contact portion having at least one contact portion, Figure 8 (c) where the interconnection portion 25 is located) is provided with a partial contact portion of a contact portion, Figure 8 Partial contact portions with two contact portions (d) at the location of the interconnection portion 25) are all within the scope of protection of this application. Figure 8 (a), (b), (c), and (d) are only schematic diagrams within a confluence area. Figure 8 One, two or three of the above situations (a), (b), (c) and (d) can also be located in different confluence areas, or, Figure 8 (a), (b), (c), and (d) may also be located in areas corresponding to different cells in a photovoltaic module, and the rest that are not fully listed are within the scope of protection of this application.

[0055] It should be noted that, in the present application, the convergence conditions in the convergence area may include but are not limited to the following examples. In the first case, an interconnection and a continuous convergence electrode are provided in the convergence area, and convergence is achieved through the interconnection and the continuous convergence electrode; in the second case, only an interconnection is provided in the convergence area, and usually one interconnection is electrically connected to one collector grid line, and convergence is achieved through the interconnection in the convergence area; in the third case, in the convergence area, a convergence electrode is provided at the end of the convergence area, a larger interconnection is provided at the end of the convergence area, and a smaller interconnection is provided in the middle of the convergence area, and usually one smaller interconnection is electrically connected to one collector grid line, and convergence is achieved through the convergence electrode, the larger interconnection and the smaller interconnection in the convergence area.

[0056] The interconnect 1 is electrically connected to the collector electrodes of the cell via the interconnect portion 25. Specifically, the interconnect 1 is electrically connected to the first collector electrode 241 of the cell via the interconnect portion 25 electrically connected to the first collector electrode 241, and the interconnect 1 is electrically connected to the second collector electrode 242 of the cell via the interconnect portion 25 electrically connected to the second collector electrode 242. The extension direction of the interconnect 1 is parallel to the extension direction of the busbar region, and both are parallel to the second direction L2, and cover at least a portion of the busbar region.

[0057] In the present application, in the battery cell, the area within the two opposite boundaries of the interconnection column along the first direction L1 is the convergence area, the interconnection member 1 covers at least part of the convergence area, and at least one convergence area is provided with at least one contact portion and part of the transmission portion, that is, not only the transmission portion but also the contact portion is provided in the area where the interconnection column is located, or in other words, not only the transmission portion but also the contact portion is provided in the area where the interconnection is located, then the contact portion is electrically connected to the doped conductive layer through the passivation layer 23, that is, the bonding force between the contact portion and the doped conductive layer is stronger, the contact portion enhances the bonding force between the transmission portion and the semiconductor substrate, and can enhance the pulling force between the collector electrode and the semiconductor substrate after the interconnection portion is electrically connected to the transmission portion through the interconnection member, thereby avoiding falling off or pulling off, and improving the yield and reliability of the photovoltaic module.

[0058] In some possible embodiments, the contact portion, the transmission portion, and the collector electrode all extend in the same direction. Specifically, because carriers must be collected by the contact portion, transferred to the transmission portion, and then passed through the interconnection portion and interconnect member to achieve current collection, having the contact portion, the transmission portion, and the collector electrode all extend in the same direction can increase the contact area between the contact portion and the transmission portion, expand the carrier transmission channel, reduce transmission dead zones, and improve current collection and transmission efficiency.

[0059] It should be noted that the extension direction of the transmission portion and the contact portion being parallel to the extension direction of the collector electrode can include: the extension directions of the three being absolutely parallel, and the angle between the extension directions of any two of the three being less than or equal to 10°, in which case the extension directions of the three are also considered to be parallel. At least one bus region corresponding to the interconnection column electrically connected to the first collector electrode 241 can be provided with at least a portion of at least one first contact portion 2411 and a portion of the first transmission portion 2412; at least one bus region corresponding to the interconnection column electrically connected to the second collector electrode 242 can be provided with at least a portion of at least one second contact portion 2421 and a portion of the second transmission portion 2422; or at least one bus region corresponding to the interconnection column electrically connected to the first collector electrode 241 can be provided with at least a portion of at least one first contact portion 2411 and a portion of the first transmission portion 2412, and at least one bus region corresponding to the interconnection column electrically connected to the second collector electrode 242 can be provided with at least a portion of at least one second contact portion 2421 and a portion of the second transmission portion 2422, all of which are within the scope of protection of this application. It should be noted that in the present application, when the polarity is not specified, the relevant content of each component may be applicable to components of at least one of the two polarities of the relevant components of P polarity and the relevant components of N polarity. When the polarity is not specified, the comparison content of each component may be applicable to the comparison content of the relevant components of P polarity, the comparison content of the relevant components of N polarity, and the comparison content of the relevant components of P polarity and N polarity. The relevant parts will not be repeated here.

[0060] It should be noted that due to printing errors, there is no limitation on whether the contact portion exceeds the collector electrode. For example, exceeding or not exceeding is within the protection scope of this application.

[0061] It should be noted that the extension direction of a component in this application means that the component extends in a certain direction as a whole, but is allowed to bend locally in other directions. Its overall direction is its extension direction, and the size of a component in its extension direction is greater than or equal to the size in the direction perpendicular to its extension direction.

[0062] In some possible embodiments, the cell further includes a bus electrode electrically connected to the collector electrode 24, and an interconnect 25 electrically connected to the bus electrode. The relative positions of the bus electrode and the collector electrode 24 can be determined based on the fabrication sequence. For example, one fabrication sequence may be to first install the bus electrode, followed by the collector electrode 24, so that the bus electrode is located on the side of the collector electrode 24 closer to the semiconductor substrate 21. Another example is to first install the collector electrode 24, followed by the bus electrode, so that the bus electrode is located on the side of the collector electrode 24 farther from the semiconductor substrate 21. Alternatively, the bus electrode and the collector electrode's transmission portion may be integrally formed. At least a portion of at least one contact portion is provided within the horizontal projection area of ​​at least one bus electrode. The horizontal projection area of ​​the bus electrode herein refers to the area on the cell where the projection of the bus electrode is located when illuminated by light parallel to the thickness direction of the cell. The horizontal projection area of ​​at least one bus electrode may include at least one complete contact portion, or the horizontal projection area of ​​at least one bus electrode may include only a partial contact portion. Specifically, at least a portion of at least one first contact portion 2411 is provided on the horizontal projection area of ​​at least one busbar electrode electrically connected to the first collector electrode 241, and at least a portion of at least one second contact portion 2421 is provided on the horizontal projection area of ​​at least one busbar electrode electrically connected to the second collector electrode 242. This also enhances the tension between the collector electrode and the semiconductor substrate after the interconnection portion is electrically connected to the transmission portion via the interconnect, preventing it from falling off or pulling apart. Furthermore, since at least a portion of the contact portion is provided on the horizontal projection area of ​​the busbar electrode, the contact portion acts as a current conduction enhancement structure, facilitating current collection and transmission.

[0063] It should be noted that the horizontal projection area of ​​the interconnection portion in the busbar region may not overlap with the contact portion, but the tensile force is increased by relying on the overlap of the busbar electrode and the contact portion.

[0064] The bus electrode may include at least one of: a whole bus electrode, an end line 26, a frame line, and a harpoon. Figure 1 The end line 26 is usually set only in a part of the area near the edge of the battery cell along the second direction L2. The entire bus electrode is usually set in most areas of the battery cell along the second direction L2. The border line is located in the edge area along the first direction L1 and extends along the second direction L2, overlapping with multiple collector electrodes of the same polarity to avoid the problem of carrier collection failure caused by short circuit in certain positions of the collector electrode, thereby improving the reliability of carrier collection. The harpoon is usually closer to the edge of the battery than the end line 26, and is used to reduce the risk of hidden cracks in the edge area of ​​the battery.

[0065] At least a portion of at least one contact portion is disposed within the horizontal projection area of ​​at least one interconnect 25. The horizontal projection area of ​​an interconnect 25 refers to the area where the interconnect 25 is projected onto the cell when illuminated by light parallel to the thickness of the cell. This can include: at least one complete contact portion disposed within the horizontal projection area of ​​at least one interconnect 25; or at least a partial contact portion disposed within the horizontal projection area of ​​at least one interconnect 25. Specifically, at least a portion of at least one first contact portion 2411 is disposed within the horizontal projection area of ​​at least one interconnect 25 electrically connected to the first collector electrode 241, and at least a portion of at least one second contact portion 2421 is disposed within the horizontal projection area of ​​at least one interconnect 25 electrically connected to the second collector electrode 242. This also enhances the tension between the collector electrode and the semiconductor substrate after the interconnect is electrically connected to the transmission portion via the interconnect member, preventing detachment or separation. Furthermore, since at least a portion of the contact portion is disposed within the horizontal projection area of ​​the interconnect 25, the contact portion acts as a current conduction enhancement structure, facilitating current collection and transmission.

[0066] In some possible embodiments, along the first direction L1: the ratio of the length of the contact portion in the horizontal projection area of ​​the interconnection 25 to the length of the interconnection 25 is 50%-100%. Along the first direction L1: the ratio of the length of the contact portion in the horizontal projection area of ​​the interconnection 25 to the length of the interconnection 25 is large, which can further improve the bonding force and current collection effect.

[0067] For example, in the first direction L1, the ratio of the length of the contact portion in the horizontal projection area of ​​the interconnection portion 25 to the length of the interconnection portion 25 can be 50%, 55%, 58%, 60%, 63%, 65%, 70%, 72%, 75%, 78%, 80%, 82%, 85%, 90%, 92%, 95%, 99%, or 100%.

[0068] Reference Figure 1 The interconnect 25 includes a large interconnect 251 and a small interconnect 252. Along the first direction L1, the maximum dimension of the large interconnect 251 is greater than the maximum dimension of the small interconnect 252, and / or, along the second direction L2, the maximum dimension of the large interconnect 251 is greater than the maximum dimension of the small interconnect 252. For example, the maximum dimension of the large interconnect 251, close to the surface of the semiconductor substrate 21, along the first direction L1, is greater than the maximum dimension of the small interconnect 252, close to the surface of the semiconductor substrate 21, along the first direction L1. And / or, the maximum dimension of the large interconnect 251, close to the surface of the semiconductor substrate 21, along the second direction L2, is greater than the maximum dimension of the small interconnect 252, close to the surface of the semiconductor substrate 21, along the second direction L2.

[0069] Reference Figure 1In some possible embodiments, the sum of the areas of the contact portions provided within the horizontal projection area of ​​at least one large interconnect 251 is greater than or equal to the sum of the areas of the contact portions provided within the horizontal projection area of ​​the small interconnects 252. A contact portion with a larger area can disperse the stress of the large interconnect 251, further increasing the tensile force and improving the current collection capability of a single large interconnect 251. This may mean that: the sum of the areas of the contact portions provided within the horizontal projection area of ​​at least one large interconnect 251 electrically connected to the first collecting electrode 241 is greater than or equal to the sum of the areas of the contact portions provided within the horizontal projection area of ​​the small interconnect 252 electrically connected to the first collecting electrode 241, and / or the sum of the areas of the contact portions provided within the horizontal projection area of ​​at least one large interconnect 251 electrically connected to the second collecting electrode 242 is greater than or equal to the sum of the areas of the contact portions provided within the horizontal projection area of ​​the small interconnect 252 electrically connected to the second collecting electrode 242.

[0070] A large interconnect 251 of the cell can be illuminated with light parallel to the thickness direction of the cell. The sum of the projected areas of all the contact portions within the projection of the large interconnect 251 is the sum of the areas of the contact portions within the horizontal projection of the large interconnect 251. The sum of the areas of the contact portions within the horizontal projection of a small interconnect 252 is determined in a similar manner and is omitted for clarity to avoid repetition.

[0071] Reference Figure 1 In some possible embodiments, the sum of the lengths of the contact portions provided within the horizontal projection area of ​​at least one large interconnect 251 along the first direction L1 is greater than or equal to the sum of the lengths of the contact portions provided within the horizontal projection area of ​​the small interconnects 252 along the first direction L1. Longer contact portions can disperse stress in the large interconnect 251, further increasing tension and improving the current collection capability of a single large interconnect 251. This may mean that the sum of the lengths of the contact portions provided within the horizontal projection area of ​​at least one large interconnect 251 electrically connected to the first collecting electrode 241 along the first direction L1 is greater than or equal to the sum of the lengths of the contact portions provided within the horizontal projection area of ​​the small interconnects 252 electrically connected to the first collecting electrode 241 along the first direction L1, and / or the sum of the lengths of the contact portions provided within the horizontal projection area of ​​at least one large interconnect 251 electrically connected to the second collecting electrode 242 along the first direction L1 is greater than or equal to the sum of the lengths of the contact portions provided within the horizontal projection area of ​​the small interconnects 252 electrically connected to the second collecting electrode 242 along the first direction L1.

[0072] A large interconnect 251 of the cell can be illuminated with light parallel to the thickness of the cell. The sum of the lengths of all contact portions within the projection of the large interconnect 251 along the first direction L1 is the sum of the lengths of the contact portions within the horizontal projection of the large interconnect 251 along the first direction L1. The sum of the lengths of the contact portions within the horizontal projection of a small interconnect 252 along the first direction L1 is determined similarly and is omitted for repetition. The lengths of the contact portions are in a direction parallel to the first direction L1.

[0073] It should be noted that, in this application, the length of the contact portion refers to the dimension of the contact portion along the first direction L1, or in other words, the dimension along its extension direction. The length of the spacing region between adjacent contact portions along the first direction L1 refers to the dimension of the spacing region between adjacent contact portions along the first direction L1 along the first direction.

[0074] Reference Figure 1 In some possible embodiments, the number of contact portions provided within the horizontal projection area of ​​at least one large interconnect 251 is greater than or equal to the number of contact portions provided within the horizontal projection area of ​​the small interconnect 252. More contact portions can disperse the stress of the large interconnect 251, further increase the tensile force, and improve the current collection capacity of a single large interconnect 251. This may mean that the number of contact portions provided within the horizontal projection area of ​​at least one large interconnect 251 electrically connected to the first collecting electrode 241 is greater than or equal to the number of contact portions provided within the horizontal projection area of ​​the small interconnect 252 electrically connected to the first collecting electrode 241, and / or the number of contact portions provided within the horizontal projection area of ​​at least one large interconnect 251 electrically connected to the second collecting electrode 242 is greater than or equal to the number of contact portions provided within the horizontal projection area of ​​the small interconnect 252 electrically connected to the second collecting electrode 242.

[0075] A large interconnect 251 of the cell can be illuminated with light parallel to the thickness direction of the cell. The number of all contact portions within the projection of the large interconnect 251 is the number of contact portions provided within the horizontal projection area of ​​the large interconnect 251. The number of contact portions provided within the horizontal projection area of ​​a small interconnect 252 is determined in a similar manner and will not be described in detail to avoid repetition.

[0076] It should be noted that the small interconnection portion 252 here can be provided separately, or can be a thickened section of the collector electrode, which is not specifically limited.

[0077] Reference Figure 1The collector electrode 24 is divided into a first collector electrode 241 and a second collector electrode 242 with different polarities. The first collector electrode 241 and the second collector electrode 242 can be located on the same side of the semiconductor substrate 21. For example, the cell is a back-contact cell in which the collector electrodes 24 are located on the backlight side of the semiconductor substrate 21. Since there is no collector electrode on the light-facing side of the semiconductor substrate 21, it is not only more aesthetically pleasing but also less shading. Alternatively, the first collector electrode 241 and the second collector electrode 242 can be located on opposite sides of the semiconductor substrate 21, with one of the first collector electrode 241 and the second collector electrode 242 located on the backlight side of the semiconductor substrate 21 and the other on the light-facing side of the semiconductor substrate 21. The cell is a double-sided cell with collector electrodes on both sides. The first collector electrode 241 includes a first transmission portion 2412 and a plurality of first contact portions 2411. The second collector electrode 242 includes a second transmission portion 2422 and a plurality of second contact portions 2421.

[0078] In some possible embodiments, the first collector electrode 241 includes: a first transmission portion 2412 and a plurality of first contact portions 2411 spaced apart, and the second collector electrode includes: a second transmission portion 2422 and a plurality of second contact portions 2421 spaced apart. In at least one first collector electrode 241, the length M of any first contact portion 2411 along the first direction L1 is 21 and the length M of the spacing region adjacent to the first contact portion 2411 along the first direction L1 11 is greater than the length M of any second contact portion 2421 along the first direction L1 in at least one second collector electrode 242. 22 and the length M of the spacing region adjacent to the second contact portion 2421 along the first direction L1. 12 The ratio of M 21 / M 11 >M 22 / M 12 Specifically, for crystalline silicon solar cells, the first doped conductive layer 221 generally has a lower doping concentration and poorer conductivity than the second doped conductive layer 222. Therefore, by setting the first contact portion 2411 in the first collector electrode 241 electrically connected to the first doped conductive layer 221 longer, the carrier collection ability of the first doped conductive layer 221 with a lower doping concentration is promoted, which is more conducive to balancing the carrier collection of the two conductive regions, and can further improve the electrical performance of the photovoltaic module.

[0079] For example, in Figure 2 In the bifacial cell shown, electrodes are provided on both sides, and Figure 3In the back contact cell shown in which electrodes are provided only on the backlight surface, the first doped conductive layers 221 may all be P-type doped conductive layers, and the second doped conductive layers 222 may all be N-type doped conductive layers. Figure 2 In the embodiment, the first doped conductive layer 221 can be provided on the light-facing surface of the semiconductor substrate 21. During normal operation of the cell, the surface of the semiconductor substrate 21 that mainly absorbs light is its light-facing surface, and the backlight surface is opposite to the light-facing surface.

[0080] It is understandable that the aforementioned first contact portion 2411 may refer to any first contact portion 2411 of a first collector electrode 241, and the same applies to a second contact portion 2421, and no further description is given. Unless otherwise specified, the following description of a first contact portion 2411 and a second contact portion 2421 refers to the aforementioned meanings.

[0081] Here, for one first collecting electrode 241 , the length M of each first contact portion 2411 along the first direction L1 is 21 The length M of the interval area between the first contact portion 2411 adjacent to the first contact portion 2411 11 The ratios may be the same or different. The second collector electrode can refer to the first collector electrode and will not be described in detail here.

[0082] In some possible embodiments, the first collector electrode 241 includes: a first transmission portion 2412 and a plurality of first contact portions 2411 spaced apart, and the second collector electrode includes: a second transmission portion 2422 and a plurality of second contact portions 2421 spaced apart. In at least one first collector electrode 241: the length M of at least one first contact portion 2411 along the first direction L1 is 21 , which is greater than the length M of at least one second contact portion 2421 in the first direction L1 of at least one second collector electrode 242. 22 ; That is, M 21 >M 22 Specifically, for crystalline silicon solar cells, the first doped conductive layer 221 generally has a lower doping concentration and poorer conductivity than the second doped conductive layer 222. Therefore, by setting the first contact portion 2411 in the first collector electrode 241 electrically connected to the first doped conductive layer 221 longer, the carrier collection ability of the first doped conductive layer 221 with a lower doping concentration is promoted, which is more conducive to balancing the carrier collection of the two conductive regions, and can further improve the electrical performance of the photovoltaic module.

[0083] For example, the first doped conductive layer 221 may be a P-type doped conductive layer, and the second doped conductive layer 222 may be an N-type doped conductive layer.

[0084] In some possible embodiments, the first collecting electrode 241 includes: a first transmission portion 2412 and a first contact portion arranged continuously, and the second collecting electrode includes: a second transmission portion 2422 and a plurality of second contact portions 2421 arranged at intervals, and the length of the first contact portion along the first direction L1 is greater than the length of the second contact portion 2421 along the first direction L1. Specifically, generally for crystalline silicon solar cells, the first doped conductive layer 221 has a lower doping concentration and poorer conductivity than the second doped conductive layer 222. Therefore, by setting the first contact portion 2411 in the first collecting electrode 241 electrically connected to the first doped conductive layer 221 to be continuous, so as to promote the carrier collection ability of the first doped conductive layer 221 with a lower doping concentration, it is more conducive to taking into account the carrier collection balance of the two conductive areas, and can further improve the electrical performance of the photovoltaic module.

[0085] For example, the first doped conductive layer 221 can be a P-type doped conductive layer, and the second doped conductive layer 222 can be an N-type doped conductive layer. For another example, in a TOPcon (passivated contact cell), the light-facing surface of the semiconductor substrate can have a suede structure, and a PN junction can be provided on the light-facing surface of the semiconductor substrate. The conductivity of the PN junction on the light-facing surface is weaker than the tunneling oxide layer structure on the backlight surface of the semiconductor substrate. Here, the contact portion of the P-type collector electrode can be continuous, thereby balancing the collection capacity of the two types of carriers, which can further improve the electrical performance of the photovoltaic module.

[0086] In some possible embodiments, in the first direction L1, the spacing between at least one pair of adjacent first contact portions of at least one first collecting electrode is smaller than the spacing between at least one pair of adjacent second contact portions of at least one second collecting electrode. Specifically, for crystalline silicon solar cells, the first doped conductive layer 221 generally has a lower doping concentration and poorer conductivity than the second doped conductive layer 222. Therefore, by setting a smaller spacing between a pair of adjacent first contact portions of the first collecting electrode 241 electrically connected to the first doped conductive layer 221, the carrier collection capability of the first doped conductive layer 221 with a lower doping concentration is promoted, which is more conducive to balancing the carrier collection of the two conductive regions, thereby further improving the electrical performance of the photovoltaic module.

[0087] For example, the first doped conductive layer 221 may be a P-type doped conductive layer, and the second doped conductive layer 222 may be an N-type doped conductive layer.

[0088] It should be noted that, along the first direction, in the horizontal projection area of ​​the interconnection, the ratio of the length of the contact portion of one collecting electrode to the length of the interconnection may be greater than the ratio of the length of the contact portion of another collecting electrode to the length of the interconnection.

[0089] In some possible embodiments, in at least one first collecting electrode 241 , a length M of a first contact portion 2411 along the first direction L1 is 21 and the length M of the spacing region adjacent to the first contact portion 2411 along the first direction L1 11 The ratio is 0.5-10, for example, M 21 / M 11 The ratio may be 0.5, 0.8, 0.9, 1, 1.2, 1.5, 1.9, 2, 2.3, 2.5, 2.7, 3, 3.2, 3.5, 4, 4.2, 4.5, 4.8, 5, 5.3, 5.5, 5.9, 6, 6.4, 6.5, 6.7, 7, 7.2, 7.5, 7.9, 8, 8.3, 8.5, 8.9, 9, 9.1, 9.5, 9.7, 10, etc. In some possible embodiments, in at least one second collecting electrode 242, a length M of a second contact portion 2421 along the first direction L1 is 22 and the length M of the interval region adjacent to the second contact portion 2421 along the first direction L1 12 The ratio is 0.5-10, for example, M 22 / M 12 The ratio can be 0.5, 0.8, 0.9, 1, 1.2, 1.5, 1.9, 2, 2.3, 2.5, 2.7, 3, 3.2, 3.5, 4, 4.2, 4.5, 4.8, 5, 5.3, 5.5, 5.9, 6, 6.4, 6.5, 6.7, 7, 7.2, 7.5, 7.9, 8, 8.3, 8.5, 8.9, 9, 9.1, 9.5, 9.7, 10, etc. In this way, by controlling the ratio of the length of the first contact portion to the length of the spacing area between adjacent first contact portions, and / or the ratio of the length of the second contact portion to the length of the spacing area between adjacent second contact portions within the above range, it is not only beneficial to ensure the carrier collection effect of the first collecting electrode and the second collecting electrode, but also can avoid the problem that the length ratio of the first contact portion and the second contact portion is too small, which is not conducive to carrier collection, and can also avoid the problem that the length ratio of the first contact portion and the second contact portion is too large, which makes it difficult to effectively reduce costs.

[0090] Along the first direction L1, the battery cell includes two edge regions and a middle region located between the two edge regions. The size of the edge region along the first direction L1 and the size of the middle region along the first direction L1 are not limited. For example, each of the two edge regions is an edge region of the battery cell located at an edge position along the first direction L1 and within 4 cm (centimeter) of the boundary line of the battery cell in the direction perpendicular to the first direction L1. Alternatively, the edge region is the area extending from the edge interconnection portion (which can be the center of the edge interconnection portion, or can be the boundary point at either end of the opposite ends along the first direction L1) to the edge of the battery cell in the first direction L1. The middle region is the portion of the battery cell between the two edge regions.

[0091] In some possible embodiments, the sum of the areas of the contact portions located in the edge regions is greater than or equal to the sum of the areas of the contact portions located in the middle region. Specifically, in a cell, the carrier collection capacity in the edge regions is slightly weaker. Therefore, by providing contact portions with larger areas in the edge regions, the carrier collection capacity in the edge regions can be improved, so that the carrier collection capacity in the middle and edge regions is roughly balanced. This can mean that in the first collector electrode 241, the area of ​​the first contact portion 2411 located in the edge region is larger than the area of ​​the first contact portion 2411 located in the middle region, and in the second collector electrode 242, the area of ​​the second contact portion 2421 located in the edge region is larger than the area of ​​the second contact portion 2421 located in the middle region.

[0092] In some possible embodiments, the sum of the lengths of the contact portions located in the edge region along the first direction L1 is greater than or equal to the sum of the lengths of the contact portions located in the middle region along the first direction L1. Specifically, in a cell, the carrier collection capability in the edge region is slightly weaker. Therefore, by providing contact portions of greater length in the edge region, the carrier collection capability in the edge region can be improved, so that the carrier collection capability in the middle and edge regions is roughly balanced. This may mean that in the first collector electrode 241, the sum of the lengths of the first contact portions 2411 located in the edge region along the first direction L1 is greater than the sum of the lengths of the first contact portions 2411 located in the middle region along the first direction L1. In the second collector electrode 242, the sum of the lengths of the second contact portions 2421 located in the edge region along the first direction L1 is greater than the sum of the lengths of the second contact portions 2421 located in the middle region along the first direction L1.

[0093] In some possible embodiments, the number of contact portions located in the edge region is greater than or equal to the number of contact portions located in the middle region. Specifically, in a cell, the carrier collection capacity in the edge region is slightly weaker. Therefore, by providing more contact portions in the edge region, the carrier collection capacity in the edge region can be improved, so that the carrier collection capacity in the middle and edge regions is roughly balanced. This can mean that in the first collector electrode 241, the number of first contact portions 2411 located in the edge region is greater than the number of first contact portions 2411 located in the middle region, and in the second collector electrode 242, the number of second contact portions 2421 located in the edge region is greater than the number of second contact portions 2421 located in the middle region.

[0094] In some possible embodiments, in at least one collecting electrode, the length of at least one contact portion located at the outermost edge along the first direction L1 is greater than the length of at least one contact portion located in the middle along the first direction L1. This may mean that in at least one first collecting electrode 241, the length of the first contact portion 2411 located at the outermost edge along the first direction L1 is greater than the length of the first contact portion 2411 located in the middle along the first direction L1. Furthermore, in at least one second collecting electrode 242, the length of the second contact portion 2421 located at the outermost edge along the first direction L1 is greater than the length of the second contact portion 2421 located in the middle along the first direction L1. Specifically, in a cell, the carrier collection capability of the collector electrodes at the outermost edge along the first direction is slightly weaker. Therefore, by providing longer contact portions at the outermost edge, the carrier collection capability at the edge can be improved, so that the carrier collection capability at the middle and edge positions is roughly balanced.

[0095] In some possible embodiments, in the second direction L2, at least one edge collector electrode located at the edge is intermittently arranged, and the interconnect 1 and / or the bus region passes through at least part of the intermittent position. It should be noted that in the case of a back-contact cell in which the collector electrode is arranged only on the backlight side, the edge collector electrode here may refer to: all collector electrodes in the area from the outermost interconnection portion along the second direction L2 to the edge of the cell, and all collector electrodes in the area from the outermost interconnection portion along the second direction L2 to the edge of the cell are intermittently arranged. In the case of a bifacial cell in which the collector electrodes are arranged on both the backlight side and the light-facing side, the edge collector electrode here may refer to: the outermost edge collector electrode along the second direction L2, and the outermost edge collector electrode along the second direction L2 is intermittently arranged. In the first direction L1, the ratio of the length of a contact portion of the edge collector electrode along the first direction L1 to the length of the aforementioned spacing region adjacent to the contact portion along the first direction L1 is different from the ratio of the length of a contact portion of the remaining collector electrodes along the first direction L1 to the length of the aforementioned spacing region adjacent to the contact portion along the first direction L1. The remaining collector electrodes here refer to collector electrodes located at other positions other than the edge position in the second direction. Specifically, there is a risk of hidden cracks or splits at the edge of the battery cell along the second direction L2. Therefore, in the second direction L2, at least one edge collector electrode located at the edge is intermittently arranged, and the interconnector 1 and / or the busbar area passes through at least part of the intermittent position. In this case, no collector electrode is arranged below the interconnector 1 at the edge position along the second direction L2, which can appropriately reduce the risk of hidden cracks at the edge position along the second direction L2. In addition, if the ratio of the length of a contact portion along the first direction L1 to the length of the aforementioned spacing region adjacent to the contact portion along the first direction L1 is different between the edge collector electrode and the remaining collector electrodes, a selective design can be made based on the different requirements for conductivity and bonding strength of the edge collector electrode and the remaining collector electrodes. For example, the ratio of the length of a contact portion along the first direction L1 to the length of the aforementioned spacing region adjacent to the contact portion along the first direction L1 is greater than the ratio of the length of a contact portion along the first direction L1 to the length of the aforementioned spacing region adjacent to the contact portion along the first direction L1 in the remaining collector electrodes. Specifically, due to the intermittent arrangement of the edge collector electrodes, the area in which the edge collector electrodes are arranged is relatively reduced. This arrangement can increase the carrier or current collection capability of the edge collector electrodes, thereby avoiding the difference in current collection capability between the edge collector electrodes and the remaining collector electrodes. The difference in current collection capability between the edge collector electrode and the remaining collector electrodes can also be avoided by increasing the area of ​​the contact portion of the edge collector electrode.For example, the sum of the areas of the contact portions in one edge collector electrode is greater than the sum of the areas of the contact portions in one of the remaining collector electrodes. Specifically, due to the discontinuous arrangement of the edge collector electrodes, the arrangement area of ​​the edge collector electrodes is relatively reduced. Therefore, by increasing the area of ​​the contact portions in the edge collector electrodes, the carrier or current collection capability of the edge collector electrodes is increased, thereby avoiding the difference between the current collection capability of the edge collector electrodes and the current collection capability of the remaining collector electrodes. For another example, the sum of the lengths of the contact portions along the first direction L1 in one edge collector electrode is greater than the sum of the lengths of the contact portions along the first direction L1 in one of the remaining collector electrodes. This can also increase the carrier or current collection capability of the edge collector electrodes, thereby avoiding the difference between the current collection capability of the edge collector electrodes and the current collection capability of the remaining collector electrodes. For another example, the number of contact portions in an edge collecting electrode is greater than the number of contact portions in one of the remaining collecting electrodes, which can also increase the carrier or current collection capacity of the edge collecting electrode, thereby avoiding the difference in current collection capacity between the edge collecting electrode and the remaining collecting electrodes.

[0096] In some possible embodiments, the height of the contact portion is h1, and the height of the transmission portion is h2, where 0.08 ≤ h1 / h2 ≤ 0.8. Using the above technical solution, the contact portion is formed after the passivation layer is formed, and then the transmission portion is formed on the contact portion. This allows the contact portion to be made of a variety of metals. In some possible embodiments, the material of the contact portion can be selected from one or more of Al (aluminum), Zn (zinc), Fe (iron), Co (cobalt), Mg (magnesium), Ag (silver), Ni (nickel), Au (gold), Pd (palladium), and their alloys. The transmission portion can be formed from a base metal paste. Furthermore, the contact portion is formed using a thinner paste layer that penetrates the passivation layer, eliminating the need for grooves in the passivation layer to form the contact portion, which would compromise the passivation effect. Compared to the prior art method of burning silver paste through the passivation layer to form a single silver electrode, this significantly reduces the amount of silver paste required to fabricate the entire cell electrode structure. The contact portion provides a conductive contact while preventing base metal diffusion toward the semiconductor substrate, ensuring electrical efficiency while reducing the overall manufacturing cost of the electrode structure.

[0097] More specifically, if h1 / h2 is too small, the height h1 of the contact portion is too low, the metal content of the contact portion that effectively passes through the passivation layer will be too little, and the portion that does not effectively pass through the passivation layer will increase, which not only destroys the passivation layer structure and causes the loss of the passivation effect, but also fails to form an effective metal contact between the contact portion and the doped conductive layer and the transmission portion, thereby reducing the ability to transmit carriers. In addition, if the height of the contact portion is too low, it is more likely to form a discontinuous contact portion, such as a scattered contact portion. The discontinuous contact portion cannot be effectively connected to the nearby contact portion, and cannot form a good metal contact in the direction parallel to the semiconductor substrate, which ultimately leads to an increase in resistance.

[0098] If h1 / h2 is too large, the height h1 of the contact part is higher, which will result in more consumption of metal raw materials in the contact part and increased costs; in addition, since the glass and organic matter contained in the contact part slurry have strong fluidity, they are easy to flow and diffuse before solidification, resulting in severe light blocking and corrosion of the passivation layer (lead in the glass will corrode the passivation layer), reducing the light absorption rate and passivation effect; at the same time, the height h2 of the transmission part is low, which can easily cause the transmission part to be disconnected, affecting current transmission.

[0099] In view of the above two situations, in this application, 0.08≤h1 / h2≤0.8, that is, the ratio of the height of the contact part to the height of the transmission part h1 / h2 is within a reasonable range. This is the result of comprehensive consideration of the shading problem of the transmission part and the contact part, the metal contact effect, and the ability to transmit carriers. While ensuring the current transmission efficiency, it is beneficial to the welding effect of the welding strip and ensures the product yield.

[0100] For example, h1 / h2 can be 0.08, 0.09, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, etc.

[0101] Specifically, the ratio of the height h1 of the first contact portion 2411 of the first collecting electrode 241 to the height h2 of the first transmission portion 2412 is 0.08 to 0.8, and / or the ratio of the height h1 of the second contact portion 2421 of the second collecting electrode 242 to the height h2 of the second transmission portion 2422 is 0.08 to 0.8.

[0102] In some possible embodiments, along the second direction L2, the width of the contact portion is W1, the width of the transmission portion is W2, and 0.04≤W1 / W2≤0.5, to ensure that the contact area between the contact portion and the transmission portion is within a reasonable range, thereby improving current transmission efficiency while reducing the difficulty of forming the contact portion and improving processing efficiency. For example, W1 / W2 can be 0.04, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, etc.

[0103] Specifically, the ratio of the width W1 of the first contact portion 2411 of the first collecting electrode 241 to the width W2 of the first transmission portion 2412 is 0.04 to 0.5, and / or the ratio of the width W1 of the second contact portion 2421 of the second collecting electrode 242 to the width W2 of the second transmission portion 2422 is 0.04 to 0.5.

[0104] It is understood that the width of the transmission portion may be different at different locations. Therefore, the width of the transmission portion W2 in this application can refer to the average width of multiple locations of the transmission portion or the maximum width of the transmission portion. The determination method of the width mentioned in this application is similar to this, and to avoid repetition, it will not be repeated here.

[0105] In some possible embodiments, the interconnection column includes interconnections 25 of at least two sizes along the first direction L1. Thus, the interconnection column has at least two boundaries along the first direction L1, and the confluence region also has at least two boundaries along the first direction L1. That is, both boundaries of the confluence region along the first direction L1 may coincide with both boundaries of the outermost interconnections in the interconnection column. Alternatively, one boundary of the confluence region along the first direction L1 may coincide with the boundary of the outermost interconnection on the corresponding side of the interconnection column, and the other boundary may coincide with the boundary of the innermost interconnection on the corresponding side of the interconnection column. Alternatively, both boundaries of the confluence region along the first direction L1 may coincide with the boundaries of the innermost interconnection on the corresponding side of the interconnection column.

[0106] In some possible embodiments, reference Figure 6 , Figure 9 and Figure 10 , along the second direction L2, at least one interconnection column is provided with at least two contact portions spaced apart, or, referring to Figure 4 and Figure 6 , Figure 9 and Figure 10 Along the first direction L1, at least two spaced-apart contacts are provided within at least one interconnection column, or, along the second direction L2, at least one interconnection element 1 simultaneously covers at least two spaced-apart contacts. More contacts are provided within the interconnection column, within the horizontal projection area of ​​the interconnection, and beneath the interconnection element, further enhancing tension, current collection capability, and stress distribution. The at least two spaced-apart contacts herein may include: at least two spaced-apart complete contacts, at least two spaced-apart partial contacts, or at least two spaced-apart contacts overlapping the boundary of the interconnection column. Here, at least one interconnection column electrically connected to the first collector electrode 241 may be provided with at least two spaced-apart first contacts 2411, and / or at least one interconnection column electrically connected to the second collector electrode 242 may be provided with at least two spaced-apart second contacts 2421.

[0107] In some possible embodiments, at least two contact portions distributed at intervals are provided in at least one interconnection column along the first direction L1. The interconnection column here may include: each interconnection in an interconnection column along the second direction L2, and the region between two adjacent interconnections along the second direction L2 within the boundary of the interconnection column along the first direction. The boundary of the interconnection column along the first direction refers to the boundary on the two opposite sides of the interconnection column along the first direction L1. Because the confluence area is the region within the two opposite boundaries of the interconnection column in the first direction L1 in the battery cell, it can be understood that at least two contact portions distributed at intervals are provided in at least one interconnection column along a direction L1, or, referring to Figure 5 and Figure 6 Along a direction L1, at least one interconnect 25 is provided with at least two spaced-apart contact portions, or, along the first direction L1, at least one interconnect member 1 is provided with at least two spaced-apart contact portions. The number of contact portions provided on interconnect columns, interconnects, and the bottom of interconnect members further increases tension and current collection capabilities. The provision of at least two spaced-apart contact portions herein may include: a complete provision of at least two spaced-apart contact portions, a partial provision of at least two spaced-apart contact portions, or overlapping at least two spaced-apart contact portions. Here, along the first direction L1, at least one bus region corresponding to an interconnect column electrically connected to a first collector electrode 241 may be provided with at least two spaced-apart first contact portions 2411, and / or at least one bus region corresponding to an interconnect column electrically connected to a second collector electrode 242 may be provided with at least two spaced-apart second contact portions 2421.

[0108] In some possible embodiments, the sum of the areas of the contact portions within at least one interconnection column is greater than the sum of the areas of the contact portions within the remaining interconnection columns. Interconnection columns at different locations can then be designed differently based on their different requirements for current collection capacity and binding strength, further enhancing current collection capacity and binding strength. The interconnection column herein may include: each interconnection in an interconnection column along the second direction L2, and the area between two adjacent interconnections along the second direction L2 within the boundary of the interconnection column along the first direction. The boundary of the interconnection column along the first direction refers to the outermost boundary on both sides of the interconnection column that are opposite to each other along the first direction L1. The area within the interconnection column can be considered equivalent to the confluence area. For example, an interconnection column located at the edge of a cell may have weak carrier generation capacity and a greater impact on the overall binding strength. A larger contact area can be provided in the interconnection column at the edge of the cell to enhance the current collection capacity and binding strength of the edge region, thereby enhancing the reliability of the photovoltaic module during long-term service. The sum of the areas of the first contact portions 2411 within at least one interconnection column electrically connected to the first collecting electrode 241 may be greater than the sum of the areas of the first contact portions 2411 within another interconnection column electrically connected to the first collecting electrode 241; and / or the sum of the areas of the second contact portions 2421 within at least one interconnection column electrically connected to the second collecting electrode 242 may be greater than the sum of the areas of the second contact portions 2421 within another interconnection column electrically connected to the second collecting electrode 242. And / or the sum of the areas of the first contact portions 2411 within at least one interconnection column electrically connected to the first collecting electrode 241 may be greater than the sum of the areas of the second contact portions 2421 within at least one interconnection column electrically connected to the second collecting electrode 242. The area comparison herein may be limited to comparisons within one interconnection column and another interconnection column of the same area.

[0109] In some possible embodiments, the sum of the lengths of the contact portions within at least one interconnection column is greater than the sum of the lengths of the contact portions within the remaining interconnection columns along the first direction L1. Similarly, interconnection columns located at different locations can be designed differently based on their different requirements for current collection capacity and binding force, further improving current collection capacity and binding force. Alternatively, the sum of the lengths of the first contact portions 2411 within at least one interconnection column electrically connected to the first collector electrode 241 along the first direction L1 may be greater than the sum of the lengths of the first contact portions 2411 within another interconnection column electrically connected to the first collector electrode 241 along the first direction L1; and / or the sum of the lengths of the second contact portions 2421 within at least one interconnection column electrically connected to the second collector electrode 242 along the first direction L1 may be greater than the sum of the lengths of the second contact portions 2421 within another interconnection column electrically connected to the second collector electrode 242 along the first direction L1. And / or, the sum of the lengths of the first contact portions 2411 in the first direction L1 within at least one interconnection column electrically connected to the first collector electrode 241 is greater than the sum of the lengths of the second contact portions 2421 in the first direction L1 within at least one interconnection column electrically connected to the second collector electrode 242. The length comparison herein may be limited to comparisons between interconnects within one interconnection column and another interconnection column of the same area.

[0110] In some possible embodiments, the number of contact portions in at least one interconnection column is greater than the number of contact portions in the remaining interconnection columns. Similarly, interconnection columns located at different positions can be designed differently according to their different requirements for current collection capacity and binding force, thereby further improving the current collection capacity and binding force.

[0111] The non-interconnection area refers to the area outside the interconnection area in the battery cell. Figure 9 and Figure 10, within the same area: the sum of the areas of the contact portions provided within the horizontal projection area of ​​at least one interconnection portion is greater than the sum of the areas of the contact portions provided within the non-interconnection portion area. The size of the same area is not limited here, for example, 1mm×1mm. Specifically, the horizontal projection area of ​​the interconnection portion is the area where the interconnection portion 25 and the interconnection member 1 are relatively concentrated. The sum of the areas of the contact portions within this area is larger, which can provide more stable support for the interconnection portion 25 and the interconnection member 1, enhance the bonding force between the transmission portion and the semiconductor substrate in the confluence area, effectively prevent slippage and falling off, and disperse stress, etc.; in addition, a larger area of ​​the contact portion is conducive to the efficient collection and transmission of current, improves the current transmission efficiency, and thereby improves the power generation performance of the battery cell and photovoltaic module. It may be that, within the same area: the sum of the areas of the first contact portions 2411 provided in the horizontal projection area of ​​at least one interconnection electrically connected to the first collecting electrode 241 is larger than the sum of the areas of the first contact portions 2411 provided in a non-interconnection area; and / or, within the same area: the sum of the areas of the second contact portions 2421 provided in the horizontal projection area of ​​at least one interconnection electrically connected to the second collecting electrode 242 is larger than the sum of the areas of the second contact portions 2421 provided in a non-interconnection area.

[0112] In some possible embodiments, reference Figures 9 and 10 , within the same area: the sum of the lengths of the contact portions provided in the horizontal projection area of ​​at least one interconnection portion along the first direction L1 is greater than the sum of the lengths of the contact portions provided in the non-interconnection portion area along the first direction L1. This can also provide more stable support for the interconnection portion 25 and the interconnection member 1, enhance the bonding force between the transmission portion and the semiconductor substrate in the confluence area, effectively prevent slippage and falling off, and disperse stress. In addition, a longer contact portion is conducive to the efficient collection and transmission of current, improves the current transmission efficiency, and thereby enhances the power generation performance of the cell and photovoltaic module.

[0113] In some possible embodiments, reference Figures 9 and 10 , within the same area: the number of contact portions provided in the horizontal projection area of ​​at least one interconnection portion is greater than the number of contact portions in the non-interconnection portion area, which can also provide more stable support for the interconnection portion 25 and the interconnection member 1, enhance the bonding force between the transmission portion and the semiconductor substrate in the confluence area, effectively prevent slippage and falling off, and disperse stress; moreover, the larger area of ​​the contact portion is conducive to the efficient collection and transmission of current, improves the current transmission efficiency, and thereby enhances the power generation performance of the battery cell and photovoltaic module.

[0114] In some possible embodiments, reference Figures 9 and 10, within the same area: the ratio of the length of the contact portion along the first direction L1 set in the horizontal projection area of ​​at least one interconnection portion to the length of the spacing area adjacent to the contact portion along the first direction L1 is greater than the ratio of the length of the contact portion along the first direction L1 in the non-interconnection portion area to the length of the spacing area adjacent to the contact portion along the first direction L1. This can also provide more stable support for the interconnection portion 25 and the interconnection member 1, enhance the bonding force between the transmission portion and the semiconductor substrate in the confluence area, effectively prevent slippage and falling off, and disperse stress; and it is conducive to the efficient collection and transmission of current, improves the current transmission efficiency, and thereby improves the power generation performance of the battery cell and photovoltaic module.

[0115] Figure 9 In the figure, the number of rows of contact portions provided in the horizontal projection area of ​​the interconnection portion 25 is greater than the number of rows of contact portions provided in the non-interconnection portion area. The larger number of rows can achieve the aforementioned larger contact portion areas, lengths, quantities, etc. Figure 10 In the figure, the number of rows of contact portions arranged in the horizontal projection area of ​​the interconnection portion 25 is the same as the number of rows of contact portions arranged in the non-interconnection portion area. The more densely packed contact portions can achieve the aforementioned larger contact area, length, number, etc.

[0116] In some possible embodiments, reference Figure 10 At least two rows of contact portions are provided within the horizontal projection area of ​​at least one interconnection portion 25. For example, Figure 10 Two rows of contact portions are provided within the horizontal projection area of ​​each interconnection 25. The at least two rows here may also be three, four, five, or more rows, and the direction of the rows may be parallel to the first direction L1. The sum of the areas of the contact portions provided within a row of contact portions within the horizontal projection area of ​​the interconnection is greater than the sum of the areas of the contact portions provided within an adjacent row of contact portions. For example, Figure 10 In (a) to (d), the sum of the contact areas within the first row of contacts from top to bottom within the horizontal projection of the interconnect is greater than the sum of the contact areas within the second row of contacts from top to bottom. Furthermore, within the horizontal projection of the interconnect, the contact area can be specifically designed to meet the varying requirements for bonding strength and current collection capacity at different locations, further improving the performance of the photovoltaic module.

[0117] In some possible embodiments, reference Figure 10At least two rows of contact portions are provided within the horizontal projection area of ​​at least one interconnection portion; the sum of the lengths of the contact portions provided in a row of contact portions within the horizontal projection area of ​​the interconnection portion along the first direction L1 is greater than the sum of the lengths of the contact portions provided in an adjacent row of contact portions along the first direction L1. This can also meet the different requirements for bonding force and current collection capacity at different locations, further improving the performance of the photovoltaic module. For example, Figure 10 In (a) and (d), the sum of the lengths of the contact portions arranged in a first row of contact portions from top to bottom within the horizontal projection area of ​​the interconnection portion along the first direction L1 is greater than the sum of the lengths of the contact portions arranged in an adjacent second row of contact portions from top to bottom in the first direction L1. Figure 10 The sum of the lengths along the first direction L1 of the contact portions arranged in the second row of contact portions from top to bottom within the horizontal projection area of ​​the interconnection portion in (b) and (c) is greater than the sum of the lengths along the first direction L1 of the contact portions arranged in the adjacent first row of contact portions from top to bottom.

[0118] In some possible embodiments, reference Figure 10 At least two rows of contact portions are provided within the horizontal projection area of ​​at least one interconnection portion. The number of contact portions provided in a row of contact portions within the horizontal projection area of ​​the interconnection portion is greater than the number of contact portions provided in an adjacent row of contact portions, which can also meet the different requirements for bonding force and current collection capacity at different locations, further improving the performance of the photovoltaic module. For example, Figure 10 The number of contact portions provided in the second row of contact portions from top to bottom within the horizontal projection area of ​​the interconnection portion in (b), (c) and (d) is greater than the number of contact portions provided in the adjacent first row of contact portions from top to bottom.

[0119] In some possible embodiments, the edge of the interconnection portion 25 can be physically overlapped with the contact portion to further ensure the tension. Figure 10 (c) The contact portion physically overlapping the edge of the interconnection portion 25 can be longer than the contact portion in the same row to further ensure the pulling force. The contact portions physically overlapping the edges of the same interconnection portion can be of the same or different lengths, which can be set according to actual needs.

[0120] In some possible embodiments, reference Figure 10At least two rows of contact portions are provided within the horizontal projection area of ​​at least one interconnection portion; the ratio of the length of a contact portion provided in a row of contact portions within the horizontal projection area of ​​the interconnection portion along the first direction L1 to the length of a spacing region adjacent to the contact portion along the first direction L1 is greater than the ratio of the length of a contact portion provided in an adjacent row of contact portions along the first direction L1 to the length of a spacing region adjacent to the contact portion along the first direction L1. This can also meet the different requirements for bonding strength and current collection capacity at different locations, further improving the performance of the photovoltaic module. For example, Figure 10 In (a), within the horizontal projection area of ​​the interconnection portion in the first row from top to bottom, the ratio of the length of the contact portion along the first direction L1 to the length of the spacing region adjacent to the contact portion along the first direction L1 is greater than the ratio of the length of the contact portion along the first direction L1 to the length of the spacing region adjacent to the contact portion along the first direction L1 in the adjacent second row from top to bottom.

[0121] In some possible embodiments, the number of contacts provided in a bus region or an interconnection column is 2 to 1500. If the number of contacts provided in a bus region or an interconnection column is too small, the improvement in the binding force and current collection capacity is weak. If the number of contacts provided in a bus region or an interconnection column is too large, the process for providing the contacts in a bus region or an interconnection column is more complicated. Therefore, in the present application, the number of contacts provided in a bus region or an interconnection column is 2 to 1500, which not only ensures the improvement in the binding force and current collection capacity, but also takes into account the preparation process of the contacts. Alternatively, the number of contacts provided in a bus region or an interconnection column electrically connected to the first collector electrode 241 may be 2 to 1500; and / or the number of contacts provided in a bus region or an interconnection column electrically connected to the second collector electrode 242 may be 2 to 1500. The configuration here may also include the contact portion being entirely within the confluence region or the interconnection column, the contact portion being partially within the confluence region or the interconnection column, the contact portion overlapping the boundary of the confluence region or the interconnection column, etc.

[0122] For example, the number of contacts provided in a bus region or interconnection column can be 2, 3, 5, 10, 50, 80, 100, 150, 200, 250, 300, 350, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, 1100, 1150, 1200, 1250, 1300, 1350, 1400, 1450, or 1500.

[0123] In some possible embodiments, the number of contact portions provided within the horizontal projection area of ​​an interconnection 25 is 0 to 600, where 0 may mean that no contact portion is provided within the horizontal projection area of ​​one or some small interconnections 252. Typically, contact portions are provided within the horizontal projection area of ​​most interconnections 25. Furthermore, the number of contact portions provided within the horizontal projection area of ​​an interconnection 25 is 1 to 600. Furthermore, the number of contact portions provided within the horizontal projection area of ​​an interconnection 25 is 2 to 600. If the number of contact portions provided within the horizontal projection area of ​​an interconnection 25 is too small, the improvement in the binding force and the current collection capability is weak. If the number of contact portions provided within the horizontal projection area of ​​an interconnection 25 is too large, the setting process of the contact portions provided within the horizontal projection area of ​​an interconnection 25 is more complicated. Therefore, in the present application, the number of contact portions provided within the horizontal projection area of ​​an interconnection 25 is within the above range, which not only ensures the improvement in the binding force and the current collection capability, but also takes into account the preparation process of the contact portions. The number of contact portions provided within the horizontal projection area of ​​the large interconnection and / or the small interconnection electrically connected to the first collecting electrode 241 may be 1 to 600; and / or the number of contact portions provided within the horizontal projection area of ​​the large interconnection and / or the small interconnection electrically connected to the second collecting electrode 242 may be 1 to 600. Such arrangements may also include all contact portions being located within the converging region or the array of interconnections, some contact portions being located within the converging region or the array of interconnections, or contact portions overlapping the boundary of the converging region or the array of interconnections.

[0124] For example, Figure 1 、 Figures 4 and 5 In the example, the number of contact portions provided in the horizontal projection area of ​​the large interconnection portion 251 is 2. Figure 6 In the embodiment of the present invention, the number of contact portions provided in the horizontal projection area of ​​the large interconnection is 12. For another example, the number of contact portions provided in the horizontal projection area of ​​an interconnection 25 can be 1, 3, 5, 10, 50, 80, 100, 150, 200, 250, 300, 350, 400, 450, 500, 550, or 600.

[0125] In some possible embodiments, the ratio of the total length of the contact portion along the first direction L1 in at least one confluence area to the total length of the spacing area is c, and the ratio of the total length of the contact portion along the first direction L1 in the area outside the confluence area to the total length of the spacing area is d, 1<c / d≤30, and further, 25≥c / d>1, that is, the total length of the contact portion in the confluence area is longer, which can improve the bonding strength and current collection capability. When c / d is too large, the total length of the contact portion in the confluence area is too long, resulting in higher cost. Therefore, in this application, 1<c / d≤30 is an optimized choice that comprehensively considers the bonding strength, current collection capability, and cost. It can be understood that within the horizontal projection area of ​​at least one interconnect member along the first direction L1, the ratio of the total length of the contact portion to the total length of the spacing region is c; within the area outside the interconnect member along the first direction L1, the ratio of the total length of the contact portion to the total length of the spacing region is d, and 30 ≥ c / d > 1. Alternatively, within the horizontal projection area of ​​at least one interconnect member along the first direction L1, the ratio of the total length of the contact portion to the total length of the spacing region is c; within the area outside the interconnect member along the first direction L1, the ratio of the total length of the contact portion to the total length of the spacing region is d, and 30 ≥ c / d > 1. The contact portion within the area herein may include a contact portion completely contained within the area, a contact portion partially contained within the area, or a contact portion that merely overlaps the area. Here, it can be that, in the bus region corresponding to at least one column of interconnected portions electrically connected to the first collecting electrode 241, the ratio of the total length of the first contact portion to the total length of the spacing region along the first direction L1 is c; in the region outside the bus region, the ratio of the total length of the first contact portion to the total length of the spacing region along the first direction L1 is d, 30≥c / d>1, and / or, in the bus region corresponding to at least one column of interconnected portions electrically connected to the second collecting electrode 242, the ratio of the total length of the second contact portion to the total length of the spacing region along the first direction L1 is c; in the region outside the bus region, the ratio of the total length of the second contact portion to the total length of the spacing region along the first direction L1 is d, 30≥c / d>1.

[0126] For example, c / d can be 1.2, 1.5, 5, 8, 10, 12, 15, 18, 20, 25, 28, 30. For another example, c here can be 1 to 5, such as 1, 1.1, 1.2, 1.5, 1.8, 1.9, 2, 2.3, 2.5, 2.9, 3, 3.1, 3.5, 4, 4.2, 4.5, 4.8, 5. For another example, d here can be 0.2 to 2, such as 0.2, 0.4, 0.5, 0.8, 0.9, 1, 1.1, 1.3, 1.5, 1.6, 1.9, 2.

[0127] Along the first direction L1: the length of the spacing area is M1, refer to Figure 1The length of the spacing area between the first contact portions 2411 is M 11 The length of the spacing area between the second contact portions 2421 is M 12 , where M1 can contain M 11 and / or M 21 For example, M1 here can be any M 11 , or, M1 can be multiple M 11 The average value of, or, M1 here can be any M 21 , or, M1 can be multiple M 21 The average value of M, or M1 can be multiple M 11 and M 21 The average value of .

[0128] Along the first direction L1: the length of the contact portion is M2, refer to Figure 1 , the length of the first contact portion 2411 is M 21 , the length of the second contact portion 2421 is M 22 , where M2 can contain M 21 and / or M 22 For example, M2 here can be any M 21 , or, M2 can be multiple M 21 The average value of, or, M2 here can be any M 22 , or, M2 can be multiple M 22 The average value of M, or M2 can be multiple M 21 and M 22 The average value of .

[0129] Along the first direction L1: the width of the interconnection member 1 is W3. When the width of the interconnection member 1 is equal at all locations, the width of the interconnection member 1 refers to the width of the interconnection member 1 at any location along the first direction L1. When the width of the interconnection member 1 is not equal at all locations, the width of the interconnection member 1 refers to the average value of the widths of the interconnection member 1 at multiple locations along the first direction L1, and multiple means 2 or more.

[0130] In some possible embodiments, 0.001W3≤M1≤3×W3; specifically, if the length M1 of the spacing region is too large, it is more likely to form discontinuous contact portions, such as scattered contact portions. The discontinuous contact portions cannot be effectively connected to nearby contact portions, and good metal contact cannot be formed in the direction parallel to the semiconductor substrate, which ultimately leads to increased resistance and reduced ability to transmit carriers; if the length M1 of the spacing region is too small, it will lead to a large consumption of metal raw materials in the contact portion and increased costs; in addition, since the glass and organic matter contained in the contact portion slurry have strong fluidity, they are easy to flow and diffuse before solidification, resulting in severe light blocking and corrosion of the passivation layer (lead in the glass will corrode the passivation layer), reducing the light absorption rate and passivation effect; at the same time, if the width W3 of the interconnection member 1 is too large, it will lead to more light blocking, and if the width W3 of the interconnection member 1 is too small, it will lead to increased resistance. Therefore, in the present application, the relationship between the length M1 of the spacing region and the width W3 of the interconnection member 1 is within the above range, which is the result of comprehensive consideration of factors such as resistance, carrier transmission capability, shading, and cost. It can ensure the metal contact effect, carrier transmission capability, and current transmission efficiency while helping to reduce shading and cost.

[0131] For example, M1 can be 0.001W3, 0.003W3, 0.005W3, 0.008W3, 0.01W3, 0.02W3, 0.03W3, 0.04W3, 0.05W3, 0.06W3, 0.07W3, 0.09W3, 0.1W3, 0.1W3, 0.2W3, 0.3W3, 0.4W3, 0.5W3, 0.6W3, 0.7W3, 0.8W3, 0.9W3, W3, 1.2W3, 1.5W3, 1.9W3, 2W3, 2.2W3, 2.5W3, 2.67W3, or 3W3.

[0132] In some possible embodiments, 0.01W3≤M2≤5×W3; specifically, if the length M2 of the contact portion is too large, it will lead to a large consumption of metal raw materials for the contact portion and an increase in cost; in addition, since the glass and organic matter contained in the contact portion slurry have strong fluidity, they are easy to flow and diffuse before solidification, resulting in severe light blocking and corrosion of the passivation layer (lead in the glass will corrode the passivation layer), reducing the light absorption rate and passivation effect; if the length of the contact portion is too small, it is more likely to form discontinuous contact parts, such as scattered contact parts, which cannot be effectively connected to nearby contact parts and cannot form good metal contact in the direction parallel to the semiconductor substrate, ultimately leading to increased resistance and reduced ability to transmit carriers; at the same time, if the width W3 of the interconnection member 1 is too large, it will lead to more light blocking, and if the width W3 of the interconnection member 1 is too small, it will lead to increased resistance. Therefore, in this application, the relationship between the length M2 of the contact portion and the width W3 of the interconnection member 1 is within the above range, which is the result of comprehensive consideration of factors such as resistance, carrier transmission capability, shading, and cost. It can ensure the metal contact effect, carrier transmission capability, and current transmission efficiency while helping to reduce shading and reduce costs.

[0133] For example, M2 can be 0.01W3, 0.015W3, 0.02W3, 0.025W3, 0.03W3, 0.035W3, 0.034W3, 0.045W3, 0.05W3, 0.055W3, 0.06W3, 0.065W3, 0.07W3, 0.075W3, 0.09W3, 0.098W3, 0.1W3, 0.2W3, 0.3W3, 0.4W3, 0.5W3, 0.58W3, 0.6W3, 0.63W3, 0.7W3, 0.8W3, 0.9W3, W3, 1.2W3, 1.5W3, 1.9W3, 2W3, 2.17W3, 2.5W3, 2.9W3, 3W3, 3.5W3, 3.7W3, 4W3, 4.3W3, 4.5W3, 4.8W3, 5W3.

[0134] Along the first direction L1: the length of the interconnection 25 is W4, which can be the length of a large interconnection 251 electrically connected to the first collecting electrode 241, or the average value of the lengths of multiple large interconnections 251 electrically connected to the first collecting electrode 241, or the length of a small interconnection 252 electrically connected to the first collecting electrode 241, or the average value of the lengths of multiple small interconnections 252 electrically connected to the first collecting electrode 241, or the average value of the lengths of a small interconnection 252 and a large interconnection 251 electrically connected to the first collecting electrode 241; or it can be the length of a large interconnection 251 electrically connected to the second collecting electrode 242, or the average value of the lengths of multiple large interconnections 251 electrically connected to the second collecting electrode 242, or the length of a small interconnection 252 electrically connected to the second collecting electrode 242, or the average value of the lengths of multiple small interconnections 252 electrically connected to the second collecting electrode 242, or the average value of the lengths of a small interconnection 252 and a large interconnection 251 electrically connected to the second collecting electrode 242.

[0135] In some possible embodiments, 0.001×W4≤M1≤2.5×W4, while comprehensively considering factors such as resistance, carrier transmission capability, shading, and cost, can ensure metal contact effect, carrier transmission capability, and current transmission efficiency while helping to reduce shading and cost.

[0136] For example, M1 can be 0.001W4, 0.003W4, 0.005W4, 0.009W4, 0.01W4, 0.03W4, 0.05W4, 0.09W4, 0.1W4, 0.2W4, 0.25W4, 0.3W4, 0.4W4, 0.5W4, 0.6W4, 0.7W4, 0.8W4, 0.9W4, W4, 1.33W4, 1.5W4, 1.9W4, 2W4, 2.1W4, and 2.5W4.

[0137] In some possible embodiments, 0.01×W4≤M2≤3×W4, while comprehensively considering factors such as resistance, carrier transmission capability, shading, and cost, can ensure metal contact effect, carrier transmission capability, and current transmission efficiency while helping to reduce shading and cost.

[0138] For example, M2 can be 0.01W4, 0.03W4, 0.05W4, 0.09W4, 0.1W4, 0.2W4, 0.25W4, 0.3W4, 0.4W4, 0.5W4, 0.6W4, 0.7W4, 0.8W4, 0.9W4, W4, 1.08W4, 1.1W4, 1.2W4, 1.3W4, 1.4W4, 1.5W4, 1.6W4, 1.9W4, 2W4, 2.3W4, 2.5W4, 2.8W4, and 3W4.

[0139] In some possible embodiments, along the first direction L1: the length of the spacing area is M1, and M1 is 0.2 mm to 1.5 mm. In the present application, the length M1 of the spacing area is within the above range, which is the result of comprehensive consideration of factors such as resistance, carrier transmission ability, shading, and cost. It can ensure the metal contact effect, carrier transmission ability, and current transmission efficiency while helping to reduce shading and reduce costs.

[0140] For example, M1 can be 0.2 mm, 0.3 mm, 0.5 mm, 0.8 mm, 0.9 mm, 1 mm, 1.2 mm, or 1.5 mm.

[0141] In some possible embodiments, along the first direction L1, the length of the contact portion is M2, and M2 is 0.3 mm to 3 mm. In the present application, the length M2 of the contact portion is within the above range, taking into account factors such as resistance, carrier transmission capability, light shielding, and cost. This can ensure metal contact effect and carrier transmission capability, ensure current transmission efficiency, and help reduce light shielding and cost.

[0142] For example, M2 can be 0.3mm, 0.35mm, 0.4mm, 0.5mm, 0.7mm, 0.9mm, 1mm, 1.3mm, 1.5mm, 1.8mm, 2mm, 2.2mm, 2.5mm, 2.8mm, 2.9mm, or 3mm.

[0143] In some possible embodiments, in the area corresponding to a battery cell: the number of busbar areas provided with at least a portion of at least one contact portion and a portion of a transmission portion accounts for 50% to 100% of the number of busbar areas in the area corresponding to the battery cell; it may be that at least a portion of a first contact portion 2411 and a portion of a first transmission portion 2412 are provided, and the number of busbar areas corresponding to the interconnection portion column electrically connected to the first collecting electrode 241 accounts for 50% to 100% of the number of all busbar areas in the area corresponding to the battery cell; or it may be that at least a portion of a first contact portion 2411 and a portion of a first transmission portion 2412 are provided, and the number of busbar areas corresponding to the interconnection portion column electrically connected to the first collecting electrode 241 accounts for 50% to 100% of the number of all busbar areas in the area corresponding to the battery cell; or it may be that at least a portion of a first contact portion 2411 and a portion of a first transmission portion 2412 are provided, and the number of busbar areas corresponding to the interconnection portion column electrically connected to the first collecting electrode 241 accounts for 50% to 100% of the number of The ratio of the number of busbar areas corresponding to the interconnection column electrically connected to the second collector electrode 242, which is provided with at least a portion of the second contact portion 2421 and a portion of the second transmission portion 2422, to the number of busbar areas in the region corresponding to the cell is 50% to 100%. Alternatively, the ratio of the number of busbar areas corresponding to the interconnection column electrically connected to the second collector electrode 242, which is provided with at least a portion of the second contact portion 2421 and a portion of the second transmission portion 2422, to the number of busbar areas in the region corresponding to the cell is 50% to 100%. Alternatively, without distinguishing between the first and second collector electrodes, the ratio of the number of busbar areas in the region corresponding to the cell, which is provided with at least a portion of at least one contact portion and a portion of the transmission portion, to the number of busbar areas in the region corresponding to the cell is 50% to 100%. All of these are within the scope of protection of the present application. Note that in the present application, a higher ratio of the number of busbar areas provided with at least a portion of at least one contact portion and a portion of the transmission portion significantly improves tension and current collection.

[0144] For example, in the area corresponding to a battery cell, the number of busbar areas provided with at least a portion of at least one contact portion and a portion of a transmission portion may be 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 100% of the number of busbar areas in the area corresponding to the battery cell.

[0145] For example, in the area corresponding to a battery cell: the number of busbar areas is 18, and the number of busbar areas provided with at least a portion of at least one contact portion and a portion of the transmission portion can be 18, 17, 16, 15, 14, 13, 12, 11, 10, and 9.

[0146] In some possible embodiments, within the region corresponding to a cell, the number of busbar regions provided with at least a portion of at least two spaced-apart contact portions accounts for 50% to 100% of the number of busbar regions within the region corresponding to the cell. The definition of this ratio is similar to the definition of the ratio of the number of busbar regions provided with at least a portion of at least one contact portion and a portion of a transmission portion within the region corresponding to the cell, and is not further described here. Note that in this application, a higher ratio of busbar regions provided with at least a portion of at least two contact portions and a portion of a transmission portion significantly improves tension and current collection.

[0147] For example, in the area corresponding to a battery cell, the ratio of the number of busbar areas with at least two spaced-apart contact portions to the number of busbar areas in the area corresponding to the battery cell can be 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 100%.

[0148] In some possible embodiments, the sum of the areas of the contact portion away from the semiconductor substrate within the horizontal projection region of the interconnect 25 is S1, and the area of ​​the interconnect 25 close to the semiconductor substrate is S2. The ratio of S2 to S1 is greater than 1 and less than or equal to 200. The areas here can be determined using the aforementioned projection area method. If the ratio of S2 to S1 is too small, it means that the sum of the areas of the contact portion away from the semiconductor substrate within the horizontal projection region of the interconnect 25 is large, which may result in higher costs. In addition, because the glass and organic matter contained in the contact portion slurry are highly fluid, they are prone to flow and diffusion before curing, resulting in severe light blocking and corrosion of the passivation layer (lead in the glass can corrode the passivation layer), thereby reducing light absorption and passivation effect. If the ratio of S2 to S1 is too large, it means that the sum of the areas of the contact portion away from the semiconductor substrate within the horizontal projection region of the interconnect 25 is small, resulting in weaker effects on improving the tensile force and current collection capacity. Therefore, when the ratio of S2 to S1 is within the above range, not only is the cost lower, the light blocking is reduced, the passivation effect is better, but also the tensile force and current collection capacity are better improved.

[0149] For example, the ratio of S2 to S1 can be 1.2, 1.5, 5, 10, 20, 50, 80, 100, 120, 150, 190, or 200.

[0150] In some possible embodiments, the photovoltaic module further includes a bonding material layer located at the junction of the interconnection portion 25 and the interconnection element 1. At least a contact portion is provided within the horizontal projection area of ​​at least a portion of the bonding material layer, which can also enhance the pulling force and current collection efficiency. The bonding material layer can be solder paste, solder glue, conductive glue, etc., and its composition can be selected from metals such as silver, copper, lead, bismuth, zinc, and nickel. The specific material of the bonding material layer is not limited.

[0151] In some possible embodiments, at least one transmission part and at least one interconnection part can be printed and formed in batches, or at least one transmission part and at least one interconnection part can be formed as one piece, such as by using the same base metal slurry for printing and forming in one go, which can further save process costs.

[0152] In some possible embodiments, at least one interconnection 25 is in direct contact with at least one contact portion, which may include a variety of situations: 1) the interconnection is below the collector electrode, so it is naturally in direct contact; 2) the contact portion and the interconnection are made of different materials and formed using different processes. Due to deviations in the printing process of the contact portion, some contact portions at local locations are in direct contact with the interconnection, and the interconnection 25 is in direct contact with the contact portion below. The interconnection 25 is in contact with the semiconductor substrate through the contact portion, which further increases the anchoring effect, increases the tension between the interconnection and the collector electrode, and is more conducive to current collection and transmission.

[0153] In some possible embodiments, at least one interconnection portion 25 is in indirect contact with at least one contact portion, and the contact portion may be printed first and then the interconnection portion 25 .

[0154] In some possible embodiments, the contact portion includes a honeycomb-shaped contact portion, and then part of the transmission portion can be filled in the pores of the honeycomb structure. The transmission portion and the contact portion are nested with each other, thereby improving the contact performance between the contact portion and the transmission portion, improving the conductivity of the battery cell, and improving the pulling force and structural stability at the interface between the contact portion and the transmission portion, further improving the bonding force between the transmission portion and the semiconductor substrate, and further enhancing the pulling force between the collector electrode and the semiconductor substrate after the interconnection portion is electrically connected to the transmission portion through the interconnection part, thereby avoiding falling off or pulling off; in addition, compared with precious metals, the transmission portion can be made of base metal materials, which are easier to diffuse. The holes of the honeycomb structure in the contact portion can be used as a receiving position or accommodating position for the inward diffusion of base metal elements, which can greatly avoid the compounding problems caused by the continued diffusion of base metal elements into the interior of the semiconductor substrate.

[0155] In some possible embodiments, the transmission portion is made of a base metal. By improving the current transmission and collection capabilities of the contact portion, the base metal transmission portion can achieve good electrical conductivity, thereby reducing costs. The specific type of base metal is not limited. It should be noted that the base metal material of the transmission portion can mean that, by weight, the base metal accounts for greater than or equal to 50% of the transmission portion.

[0156] For example, the material of the transmission part can be selected from: at least one of copper, nickel, chromium, lead, and aluminum, for example, a transmission part formed by copper paste or silver-coated copper paste, etc. First, the above materials have good electrical conductivity; second, the cost of the above materials is low, which can reduce the cost of the electrode; third, the above materials can be formed by low-temperature process, avoiding the penetration of the passivation layer into the silicon substrate by burning, reducing recombination, and avoiding the introduction of heat effects into the solar cell.

[0157] In some possible embodiments, the material of the contact part is selected from a burn-through slurry, and part of the transmission part is embedded in the recess of the contact part. If the material of the contact part is selected from a burn-through slurry, there is no need to groove the passivation layer, and the contact part burns through the local position of the passivation layer below it, and makes contact with the local doped conductive layer below it. The contact part burns through the local passivation layer and makes ohmic contact with the doped conductive layer, and the contact with the doped conductive layer is tighter after being burned through at medium or high temperature. Specifically, in one case, the contact part includes a honeycomb structure with a plurality of holes, and part of the transmission part is embedded in the holes in the interface area between the contact part and the transmission part; in another case, there may be a recess in the contact part in the interface area between the contact part and the transmission part, and part of the transmission part is embedded in the above-mentioned recess; one is that at the interface area between the contact part and the transmission part, part of the transmission part is filled in the above-mentioned hole and part of the transmission part is embedded in the above-mentioned recess, that is, part of the transmission part wraps the contact part, or the contact part and the transmission part are nested with each other, which improves the contact part and the transmission part. The contact performance of the battery is improved, the conductive performance of the collector electrode is improved, and the pull-out force and structural stability at the interface between the contact part and the transmission part are improved; secondly, compared with precious metals, some base metals in the transmission part are more easily diffused, and the holes and depressions in the contact part can be used as receiving positions or accommodating positions for the inward diffusion of metal elements in the transmission part, which can greatly avoid the recombination problem caused by the continued diffusion of metal elements in the transmission part into the interior of the semiconductor substrate. Therefore, the present application not only reduces the cost of the battery, but also improves the conductive performance, pull-out force and structural stability of the collector electrode, and reduces recombination.

[0158] In some possible embodiments, an organic substance is provided at least partially at the interface between the contact portion and the transmission portion, and the organic substance isolates the contact portion and the transmission portion. That is, in the interface region between the contact portion and the transmission portion, the organic substance can block the holes in the contact portion, so that the metal particles of the transmission portion cannot enter the holes. In this interface region, the organic substance can provide a certain adhesion between the contact portion and the transmission portion, and can play a role in increasing the pulling force and bonding force between the contact portion and the transmission portion. The main element in the organic substance is C, and the organic substance is usually a compound with a carbon-carbon bond (CC) or a carbon-hydrogen bond (CH) as the skeleton. The organic substance has a good bonding and pulling effect on the contact portion and the transmission portion. The different thicknesses of the organic substance here can play a role in bonding force or electrical connection.

[0159] In some possible embodiments, a plurality of metal particles are disposed on the side of the transmission portion near the contact portion. The metal particles are filled in holes or recesses on the surface of the contact portion. An organic material is disposed between the metal particles in the holes or recesses and the walls of the holes or recesses. The varying thickness of the organic material disposed between the metal particles in the holes or recesses and the walls of the holes or recesses can provide adhesion or electrical connection.

[0160] In some possible implementations, the thickness of the organic material is 0.01nm~50nm. For example, the thickness of the organic material can be 0.01nm, 0.5nm, 0.1nm, 1nm, 2nm, 3nm, 4nm, 5nm, 6nm, 7nm, 8nm, 9nm, 10nm, 15nm, 18nm, 19nm, 20nm, 25nm. 30nm, 40nm, 50nm. If the thickness of the organic material is too small, the contact part and the transmission part cannot be firmly combined together. If the thickness is too large, the body resistance of the organic material will be too large, affecting the collection of carriers and thus affecting the photoelectric conversion efficiency of the solar cell. Controlling the thickness of the organic material within the above range can not only ensure that the organic material can firmly combine the contact part and the transmission part, but also that the body resistance of the organic material will not be too large, thus ensuring efficient collection of carriers.

[0161] Preferably, the thickness of the organic material is 0.01 nm to 5 nm, for example, 0.01 nm, 0.5 nm, 1 nm, 2 nm, 3 nm, 4 nm, and 5 nm. Organic materials of such thickness can achieve electrical conductivity through a tunneling mechanism, so even if the organic material itself is non-conductive, the contact portion and the transmission portion can be electrically connected.

[0162] In some other possible implementations, the thickness of the organic material is greater than 50 nm. In the case where the thickness of the organic material is greater than 50 nm, the organic material may only play a role of adhesive force.

[0163] In some possible embodiments, along the first direction L1 , the shape of the spacing region between adjacent contact portions may be dot-shaped, line-shaped, etc., which is not specifically limited.

[0164] In some possible embodiments, the cell is at least one of a back-contact cell, a heterojunction HJT cell, a TOPCon (tunneling passivated contact) cell, or a tandem photovoltaic cell. The bottom cell of the tandem photovoltaic cell is at least one of a back-contact cell, a heterojunction HJT cell, or a TOPCon cell, and the top cell is a perovskite cell. In a back-contact cell, the collector electrode is located only on the backlight side of the semiconductor substrate. There are many different cell types.

[0165] This application also provides a photovoltaic system comprising any of the aforementioned photovoltaic modules, wherein the photovoltaic modules are arranged in an array. This photovoltaic system can be a BIPV (building integrated photovoltaic) system, such as a photovoltaic curtain wall, which uses photovoltaic glass instead of conventional glass curtain walls to both provide daylight and generate electricity. A photovoltaic roof integrates the modules into the roof. A photovoltaic skylight uses photovoltaic modules on the roof of a building to achieve the dual benefits of natural lighting and electricity production.

[0166] It should be noted that the photovoltaic system and the photovoltaic module have the same or similar beneficial effects and can be referenced to each other. In order to avoid repetition, they will not be described in detail.

[0167] It should be noted that, in this document, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or apparatus comprising the element.

[0168] The embodiments of the present invention are described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the present invention and the claims, all of which are protected by the present invention.

Claims

1. A photovoltaic module comprising: interconnects and several battery cells; The cell comprises: a semiconductor substrate; a doped conductive layer disposed on the semiconductor substrate; and a passivation layer disposed on a side of the doped conductive layer away from the semiconductor substrate. A plurality of collector electrodes are arranged on a side of the passivation layer away from the doped conductive layer, the plurality of collector electrodes extend along a first direction and are spaced apart along a second direction; the collector electrodes are divided into a first collector electrode and a second collector electrode with different polarities, the first collector electrode and the second collector electrode are located on the same side of the semiconductor substrate, or on opposite sides; the first collector electrode and / or the second collector electrode include: a transmission portion and a plurality of contact portions, the plurality of contact portions passing through the passivation layer and electrically connected to the doped conductive layer, and a spacing region exists between the contact portions adjacent to each other along the first direction; the transmission portion is arranged on a side of the contact portion away from the semiconductor substrate, and is in contact with and connected to the plurality of contact portions; a plurality of interconnects electrically connected to the collector electrode; the plurality of interconnects are arranged in a row along the second direction to form an interconnection row; in the battery cell, regions within two opposite boundaries of the interconnection row along the first direction are confluence regions, and at least one of the confluence regions is provided with at least a portion of at least one of the contact portions and a portion of the transmission portion; The interconnection member is electrically connected to the collector electrode of the battery cell through the interconnection portion; the extension direction of the interconnection member is parallel to the extension direction of the busbar area and covers at least a portion of the busbar area.

2. The photovoltaic module according to claim 1, characterized in that The battery cell further includes: a plurality of bus electrodes electrically connected to the collecting electrodes, and the interconnection portion electrically connected to the bus electrodes; at least a portion of at least one contact portion is provided within a horizontal projection area of ​​at least one of the bus electrodes.

3. The photovoltaic module according to claim 1, characterized in that The extending direction of the contact portion is parallel to the extending direction of the collecting electrode.

4. The photovoltaic module according to claim 1, characterized in that Along the second direction, at least one of the interconnection portion columns is provided with at least two contact portions distributed at intervals; and / or, Along the first direction, at least two contact portions are provided in at least one interconnection portion column and are spaced apart from each other.

5. The photovoltaic module according to claim 1, characterized in that The sum of the areas of the contact portions in at least one of the interconnection portion columns is greater than the sum of the areas of the contact portions in the remaining interconnection portion columns; and / or, The sum of the lengths of the contact portions in at least one of the interconnection portion columns along the first direction is greater than the sum of the lengths of the contact portions in the remaining interconnection portion columns along the first direction; and / or, The number of the contact portions in at least one of the interconnection portion columns is greater than the number of the contact portions in the remaining interconnection portion columns.

6. The photovoltaic module according to claim 1, characterized in that At least a portion of at least one contact portion is disposed within a horizontal projection area of ​​at least one of the interconnecting portions.

7. The photovoltaic module according to claim 6, characterized in that: Along the first direction: a ratio of a length of the contact portion in a horizontal projection area of ​​one of the interconnecting portions to a length of one of the interconnecting portions is 50%-100%.

8. The photovoltaic module according to claim 6, characterized in that: The interconnection portion includes: a large interconnection portion and a small interconnection portion, along the first direction: the maximum size of the large interconnection portion is larger than the maximum size of the small interconnection portion, and / or, along the second direction: the maximum size of the large interconnection portion is larger than the maximum size of the small interconnection portion; The sum of the areas of the contact portions provided within the horizontal projection area of ​​at least one of the large interconnections is greater than or equal to the sum of the areas of the contact portions provided within the horizontal projection area of ​​the small interconnections; and / or The sum of the lengths of the contact portions arranged in the horizontal projection area of ​​the large interconnection along the first direction is greater than or equal to the sum of the lengths of the contact portions arranged in the horizontal projection area of ​​the small interconnection along the first direction; and / or The number of the contact portions provided within the horizontal projection area of ​​the large interconnection is greater than or equal to the number of the contact portions provided within the horizontal projection area of ​​the small interconnection.

9. The photovoltaic module according to claim 1, characterized in that: In the same area: the sum of the lengths of the contact portions arranged in the horizontal projection area of ​​at least one of the interconnection portions along the first direction is greater than the sum of the lengths of the contact portions arranged in the non-interconnection portion area along the first direction; and / or In the same area: the sum of the areas of the contact portions provided in the horizontal projection area of ​​at least one of the interconnected portions is greater than the sum of the areas of the contact portions provided in the non-interconnected portion area; and / or In the same area: the number of the contact portions provided in the horizontal projection area of ​​at least one of the interconnected portions is greater than the number of the contact portions provided in the non-interconnected portion area; and / or Within the same area: the ratio of the length of the contact portion provided in the horizontal projection area of ​​at least one of the interconnected portions along the first direction to the length of the spacing area adjacent to the contact portion along the first direction is greater than the ratio of the length of the contact portion provided in the non-interconnected portion area along the first direction to the length of the spacing area adjacent to the contact portion along the first direction.

10. The photovoltaic module according to claim 1, characterized in that: Within a horizontal projection area of ​​at least one of the interconnecting portions, at least two rows of the contact portions are arranged along the second direction.

11. The photovoltaic module according to claim 10, characterized in that: The sum of the lengths of the contact portions arranged in a row of the contact portions within the horizontal projection area of ​​the interconnection portion along the first direction is greater than the sum of the lengths of the contact portions arranged in an adjacent row of the contact portions along the first direction; and / or, The sum of the areas of the contact portions provided in a row of the contact portions within the horizontal projection area of ​​the interconnection portion is greater than the sum of the areas of the contact portions provided in the non-interconnection portion area; and / or The number of the contact portions provided in one row of the contact portions within the horizontal projection area of ​​the interconnection portion is greater than the number of the contact portions provided in an adjacent row of the contact portions; and / or, The ratio of the length of the contact portion arranged in a row of the contact portions within the horizontal projection area of ​​the interconnection portion along the first direction to the length of the spacing region adjacent to the contact portion along the first direction is greater than the ratio of the length of the contact portion arranged in an adjacent row of the contact portions along the first direction to the length of the spacing region adjacent to the contact portion along the first direction.

12. The photovoltaic module according to claim 1, characterized in that In at least one of the confluence areas along the first direction: the ratio of the total length of the contact portion to the total length of the spacing area is c; in the area outside the confluence area along the first direction: the ratio of the total length of the contact portion to the total length of the spacing area is d, 1<c / d≤30.

13. The photovoltaic module according to claim 1, characterized in that Along the first direction: the length of the spacing region is M1, the length of the contact portion is M2, and the width of the interconnection member is W3; 0.001W3≤M1≤3×W3; and / or, 0.01W3≤M2≤5×W3.

14. The photovoltaic module according to claim 1, characterized in that Along the first direction: the length of the spacing area is M1, the length of the contact portion is M2, and the length of the interconnection portion is W4; 0.001W4≤M1≤2.5×W4; and / or, 0.01W4≤M2≤3×W4.

15. The photovoltaic module according to claim 1, characterized in that The height of the contact portion is h1, the height of the transmission portion is h2, 0.08≤h1 / h2≤0.8; and / or, Along the second direction, the width of the contact portion is W1, the width of the transmission portion is W2, and 0.04≤W1 / W2≤0.

5.

16. The photovoltaic module according to any one of claims 1 to 15, characterized in that: Along the first direction: the length of the spacing area is M1, the length of the contact portion is M2, M1 is 0.2 mm to 1.5 mm, and M2 is 0.3 mm to 3 mm.

17. The photovoltaic module according to any one of claims 1 to 15, characterized in that: The first collecting electrode includes: a first transmission portion and a plurality of first contact portions arranged at intervals; the second collecting electrode includes: a second transmission portion and a plurality of second contact portions arranged at intervals; a length of at least one first contact portion in at least one of the first collecting electrodes along the first direction is greater than a length of at least one second contact portion in at least one of the second collecting electrodes along the first direction; Alternatively, the first collecting electrode includes: a first transmission portion and a continuously arranged first contact portion, and the second collecting electrode includes: a second transmission portion and a plurality of spaced second contact portions, and the length of the first contact portion along the first direction is greater than the length of the second contact portion along the first direction.

18. The photovoltaic module according to any one of claims 1 to 15, characterized in that: The first collector electrode includes: a first transmission portion and a plurality of first contact portions arranged at intervals; the second collector electrode includes: a second transmission portion and a plurality of second contact portions arranged at intervals; In at least one of the first collecting electrodes, the ratio of the length of a first contact portion along the first direction to the length of the spacing region adjacent to the first contact portion along the first direction is greater than the ratio of the length of a second contact portion along the first direction to the length of the spacing region adjacent to the second contact portion along the first direction in at least one of the second collecting electrodes.

19. The photovoltaic module according to any one of claims 1 to 15, characterized in that: The first collector electrode includes: a first transmission portion and a plurality of first contact portions arranged at intervals; the second collector electrode includes: a second transmission portion and a plurality of second contact portions arranged at intervals; In at least one of the first collecting electrodes: a ratio of a length of one of the first contact portions along the first direction to a length of the spacing region adjacent to the first contact portion along the first direction along the first direction is 0.5-10; and / or, In at least one of the second collecting electrodes, a ratio of a length of one of the second contact portions along the first direction to a length of the spacing region adjacent to the second contact portion along the first direction is 0.5-10.

20. The photovoltaic module according to any one of claims 1 to 15, characterized in that: The first collector electrode includes: a first transmission portion and a plurality of first contact portions arranged at intervals; the second collector electrode includes: a second transmission portion and a plurality of second contact portions arranged at intervals; In the first direction, a distance between at least one pair of adjacent first contact portions in at least one first collecting electrode is smaller than a distance between at least one pair of adjacent second contact portions in at least one second collecting electrode.

21. The photovoltaic module according to any one of claims 1 to 15, characterized in that: The material of the contact part is selected from at least one of nickel, silver, aluminum, zinc, iron, cobalt, magnesium, gold, and palladium; the material of the transmission part is selected from base metals, and / or at least one of the transmission parts and at least one of the interconnection parts are integrally formed using the same material.

22. The photovoltaic module according to any one of claims 1 to 15, characterized in that: The material of the contact portion is selected from a burn-through slurry, and a portion of the transmission portion is embedded in a recess of the contact portion.

23. The photovoltaic module according to any one of claims 1 to 15, characterized in that: The transmission part has a plurality of metal particles on the side close to the contact part. The metal particles are filled in holes or depressions on the surface of the contact part. Organic matter is arranged between the metal particles in the holes or depressions and the walls of the holes or depressions.

24. The photovoltaic module according to any one of claims 1 to 15, characterized in that: The cell is at least one of a back contact cell, a heterojunction HJT cell, a TOPCon cell, and a stacked photovoltaic cell, wherein the bottom cell of the stacked photovoltaic cell is at least one of a back contact cell, a heterojunction HJT cell, and a TOPCon cell, and the top cell is a perovskite cell.

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