Solar cell and photovoltaic module

Abstract

The invention provides a solar cell. The solar cell comprises a cell body; a barrier layer disposed on the cell body; the plurality of electrode structures are arranged on the barrier layer, and each electrode structure comprises an organic layer and an electrode layer which are sequentially stacked; wherein the electrode layer comprises an organic carrier and first metal particles, and the organic material of the organic layer is the same as the organic material of the organic carrier. Compared with the condition that an electrode is formed on the barrier layer through screen printing in the prior art, the organic layer is additionally arranged between the barrier layer and the electrode layer, the binding force between the barrier layer and the electrode layer can be increased, and the reliability of the solar cell is improved. The combination between the organic layer and the electrode layer can be firmer by adopting the same organic material, so that the binding force between the organic layer and the electrode layer is improved, and the reliability of the solar cell is improved. The invention further provides a photovoltaic module comprising the solar cell.

Description

Technical Field

[0001] The present application relates to the field of solar cells, and in particular, to a solar cell and a photovoltaic module comprising the solar cell. Background Art

[0002] Solar cells are devices that use the photoelectric effect of semiconductor materials to convert solar energy into electrical energy. In solar cells, when sunlight shines on semiconductor materials, the atoms in the semiconductor materials are affected by photons and produce transition reactions, forming electron-hole pairs, which form photo-generated voltage under the influence of electric field forces. In order to utilize the photo-generated voltage, electrodes are usually formed on P-type semiconductors and N-type semiconductors. When electrons and holes gather on p-type semiconductors and n-type semiconductors, they flow through these electrodes to the external circuit, forming current, thereby realizing the conversion of light energy into electrical energy.

[0003] In current technology, conductive paste is usually directly printed by screen printing technology to form electrodes to collect electrons and holes. However, the electrodes formed by this method of directly printing conductive paste have problems such as poor contact and poor bonding between the electrodes and other structures in the solar cell, which affects the photoelectric conversion efficiency and reliability of the solar cell. Summary of the invention

[0004] In view of this, the present application provides a solar cell and a photovoltaic module to solve the above-mentioned problems existing in the prior art.

[0005] Specifically, according to the first aspect of the present application, a solar cell is provided, comprising: a cell body; a barrier layer, arranged on the cell body; a plurality of electrode structures, arranged on the barrier layer, and the electrode structure comprises an organic layer and an electrode layer stacked in sequence; wherein the electrode layer comprises an organic carrier and first metal particles, and the organic material of the organic layer is the same as the organic material of the organic carrier.

[0006] The solar cell provided by the present application can increase the bonding force between the barrier layer and the electrode layer by additionally providing an organic layer between the barrier layer and the electrode layer, prevent the electrode layer from falling off, and improve the reliability of the solar cell. On this basis, the use of the same organic material can make the bonding between the organic layer and the electrode layer more firm, thereby further improving the bonding force between the organic layer and the electrode layer, and further improving the reliability of the solar cell.

[0007] In some embodiments, the thickness of the organic layer is from 0.01 nm to 50 nm.

[0008] In some embodiments, the thickness of at least one location in the organic layer is between 0.01 nm and 5 nm.

[0009] In some embodiments, the thickness of at least one location in the organic layer is between 0.01 nm and 10 nm.

[0010] In some embodiments, the width of the organic layer is greater than or equal to the width of the electrode layer.

[0011] In some embodiments, the projected area of ​​the organic layer on the battery body completely covers the projected area of ​​the electrode layer on the battery body.

[0012] In some embodiments, the material of the first metal particles includes copper, silver, nickel, aluminum, alloys thereof, or any combination thereof.

[0013] In some embodiments, the first metal particles include at least one of spherical particles and flake particles.

[0014] In some embodiments, the first metal particles in the electrode layer pass through the organic layer to contact the barrier layer.

[0015] In some embodiments, the organic layer includes at least one conductive contact point within 50 μm, and the thickness of the organic layer at the conductive contact point is 0.01 nm-10 nm; or, the first metal particles in the electrode layer at the conductive contact point pass through the organic layer to contact the barrier layer.

[0016] In some embodiments, the organic layer is a conductive organic layer.

[0017] In some embodiments, the organic layer includes second metal particles, and the particle size of the second metal particles is smaller than the particle size of the first metal particles.

[0018] In some embodiments, the organic material in the organic layer is a conductive organic material.

[0019] In some embodiments, the first metal particles include flake-like particles, and the flake-like particles include single-layer flake-like particles.

[0020] In some embodiments, the first metal particles include plate-shaped particles, and the outline of the plate-shaped particles is surrounded by a smooth curved surface.

[0021] In some embodiments, the second metal particles have a particle size of 1-20 nm.

[0022] In some embodiments, the barrier layer is a unitary structure.

[0023] In some embodiments, the blocking layer includes a plurality of sub-blocking layers, wherein the plurality of sub-blocking layers correspond one-to-one to the plurality of electrode structures.

[0024] In some embodiments, the barrier layer is a metal layer or a transparent conductive oxide layer.

[0025] In some embodiments, the material of the transparent conductive oxide layer includes a combination of one or more of indium tin oxide (ITO), indium tungsten oxide (IWO), and indium titanium oxide (ITiO).

[0026] In some embodiments, the material of the metal layer includes a combination of one or more of nickel, silver, tin, and aluminum.

[0027] In some embodiments, the battery body includes a semiconductor substrate and a doped semiconductor layer disposed on the semiconductor substrate, the barrier layer is in contact with the doped semiconductor layer, and the electrode structure is electrically connected to the doped semiconductor layer through the barrier layer.

[0028] In some embodiments, the battery body includes a semiconductor substrate and a doped semiconductor layer and a dielectric layer sequentially arranged on the semiconductor substrate, the dielectric layer has a plurality of openings, one opening corresponds to an electrode structure, the barrier layer contacts the doped semiconductor layer through the opening, and the electrode structure is electrically connected to the doped semiconductor layer through the barrier layer.

[0029] According to a second aspect of the present application, a photovoltaic assembly is provided, comprising a plurality of cell strings, the cell strings comprising a plurality of solar cells and a plurality of interconnecting members, the interconnecting members being used to connect the plurality of solar cells in series; wherein the solar cell is any solar cell described in the first aspect of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other implementation plans can be obtained based on these drawings without paying creative work.

[0031] Figure 1 A schematic structural diagram of a solar cell according to some embodiments of the present application is shown.

[0032] Figure 2 A schematic structural diagram of a battery body according to some embodiments of the present application is shown.

[0033] Figure 3 Shown are schematic structural diagrams of battery bodies according to some other embodiments of the present application.

[0034] Figure 4 Schematic diagrams of the structures of solar cells according to some other embodiments of the present application are shown.

[0035] Figure 5 shows SEM images of the barrier layer, the organic layer and the electrode layer in the solar cell according to some embodiments of the present application, Figure 5 B is Figure 5 Magnified view of the boxed area in A.

[0036] Figure 6 SEM images of the barrier layer, the organic layer, and the electrode layer in the solar cell according to some other embodiments of the present application are shown.

[0037] Figure 7 SEM images of a barrier layer, an electrode layer, and an organic layer in a solar cell according to some embodiments of the present application are shown.

[0038] Figure 8 SEM images at a barrier layer, an electrode layer, and an organic layer in a solar cell in the case where second metal particles are included in an organic layer according to some embodiments of the present application are shown.

[0039] Among them, the figure numbers are as follows: 100 represents a solar cell; 10 represents a battery body, 101 represents a semiconductor substrate, 102 represents a doped semiconductor layer, 103 represents a dielectric layer, and 104 represents an opening; 20 represents a blocking layer, and 201 represents a sub-blocking layer; 30 represents an electrode structure, 301 represents an organic layer, and 302 represents an electrode layer. DETAILED DESCRIPTION

[0040] The present application will be described clearly and completely below in conjunction with the embodiments and drawings of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. All other embodiments that can be obtained by a person of ordinary skill in the art based on the embodiments in the present application belong to the scope of protection of the present application.

[0041] In this application, the terms "first" and "second" are only used to describe the features for the purpose and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Features defined as "first" and "second" may explicitly or implicitly include at least one of the defined features. It is understood that "at least one" includes one or more, where "plurality" generally means at least two, such as two, three, four, five, six, etc., unless otherwise clearly and specifically defined.

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

[0043] In the present application, the terms "one embodiment", "some embodiments", "an example", "some examples", "examples", "specific examples" or "some examples" etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment, example or example are included in at least one embodiment, example or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment, example or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments, examples or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments, examples or examples described in this specification and the features of the different embodiments, examples or examples, without contradiction.

[0044] The photovoltaic module of the present application includes a stacked transparent cover plate, an adhesive film, a battery string and a packaging back plate and other structures for photovoltaic power generation.

[0045] In photovoltaic modules, the transparent cover is used to protect the internal cells and other materials from the external environment. It has high light transmittance to ensure the effective absorption of solar energy. It can be a transparent polymer film such as ethylene-tetrafluoroethylene copolymer film, or transparent glass such as ultra-white photovoltaic glass. The adhesive film is mainly used to bond the solar cell string to the transparent cover and the encapsulation backplane. It can be ethylene-octene copolymer (POE), ethylene-vinyl acetate copolymer (EVA), etc. The encapsulation backplane is located at the outermost layer on the back of the photovoltaic module. It is used to encapsulate and protect the solar cell string from the erosion of the external environment and plays a role in weather-resistant insulation. It can be made of materials such as glass or organic polymer film. The battery string is used to convert solar energy into electrical energy and is the core part of the photovoltaic module.

[0046] A photovoltaic module generally includes a plurality of cell strings, which may be connected in series and / or in parallel. Each cell string includes a plurality of solar cells 100 and a plurality of interconnecting members, and the interconnecting members are used to connect the plurality of solar cells in series. It is understood that the interconnecting members are electrically connected to the electrode structures of the plurality of solar cells 100, thereby connecting the plurality of solar cells in series. Here, the solar cell 100 includes any of the solar cells described below in the present application. In addition, the above-mentioned interconnecting members may be, for example, welding strips, metal wires, conductive tapes, and the like.

[0047] Figure 1 FIG. 1 is a schematic diagram showing the structure of a solar cell 100 according to some embodiments of the present application. Figure 1It can be seen that the solar cell 100 includes a cell body 10 , a barrier layer 20 disposed on the cell body 10 , and a plurality of electrode structures 30 disposed on the barrier layer 20 .

[0048] Figure 2 FIG. 1 shows a schematic structural diagram of a battery body 10 according to some embodiments of the present application. Figure 2 It can be seen that the battery body 10 includes a semiconductor substrate 101 and a doped semiconductor layer 102 disposed on the semiconductor substrate 101. The semiconductor substrate 101 includes a first surface and a second surface opposite to each other, and the doped semiconductor layer 102 can be disposed on the first surface and / or the second surface of the semiconductor substrate 101. It can be seen that Figure 2 The illustrated example shows a case where the doped semiconductor layer 102 is disposed on only one surface of the semiconductor substrate 101. It is understood that the doped semiconductor layer 102 may also be disposed on both surfaces of the semiconductor substrate 101, and those skilled in the art may select the desired one. In this case, no dielectric layer is disposed between the doped semiconductor layer 102 and the barrier layer.

[0049] In some embodiments, the semiconductor substrate 101 includes a silicon substrate, a germanium substrate, a silicon-germanium substrate, etc. When the semiconductor substrate 101 is a silicon substrate, it can be single crystal silicon, polycrystalline silicon, amorphous silicon, microcrystalline silicon, etc., which is not limited in this application. In some embodiments, the material of the doped semiconductor layer 102 can be single crystal silicon, polycrystalline silicon, amorphous silicon, microcrystalline silicon, nanocrystalline silicon, etc., which is not limited in this application.

[0050] Figure 3 Schematic diagrams of the structure of the battery body 10 according to some other embodiments of the present application are shown. Figure 3 It can be seen that the battery body 10 includes a semiconductor substrate 101, a doped semiconductor layer 102 and a dielectric layer 103 sequentially stacked on the semiconductor substrate 101, and the dielectric layer 103 has a plurality of openings 104. It can be seen that Figure 3 Only the case where the doped semiconductor layer 102 and the dielectric layer 103 are stacked on only one surface of the semiconductor substrate 101 is shown. It is understood that the doped semiconductor layer 102 and the dielectric layer 103 can also be stacked on both surfaces of the semiconductor substrate 101 at the same time, and those skilled in the art can choose as needed. In some embodiments, the material of the dielectric layer 103 can be one or more of silicon nitride, silicon oxide, silicon oxynitride, aluminum oxide, and amorphous silicon. Of course, other materials can also be used, and this application does not further limit this.

[0051] In addition, the dielectric layer 103 may be a single-layer structure or a multi-layer structure. In some examples, the dielectric layer 103 may include a passivation layer, or may include other possible layers such as an anti-reflection layer, or may include a passivation layer and an anti-reflection layer stacked. The material of the passivation layer may be, for example, one or more of amorphous silicon and aluminum oxide, and the material of the anti-reflection layer may be, for example, one or more of silicon nitride, silicon oxide, and silicon oxynitride.

[0052] Continue to refer Figure 1 , the barrier layer 20 is disposed on the battery body 10. Providing the barrier layer 20 on the battery body 10 can protect the battery body 10 and reduce the risk of mechanical damage to the battery body 10 during the manufacturing process of the electrode structure 30. In some examples, the barrier layer 20 can also prevent some elements in the electrode structure 30 from diffusing into the battery body 10, affecting the photoelectric conversion efficiency of the solar cell 100. In other examples, the barrier layer 20 can also reduce the lateral transmission resistance of the carriers, improve the transmission efficiency of the carriers, and thus improve the photoelectric conversion efficiency.

[0053] The barrier layer 20 may be an integrated structure, that is, the barrier layer 20 is a whole layer structure, or may include multiple sub-barrier layers 201, that is, multiple independent structures. It is understood that Figure 1 The illustrated case is a case where the barrier layer 20 is an integral structure. Figure 4 The barrier layer 20 includes a plurality of sub-barrier layers 201. In addition, the barrier layer 20 may be a metal layer or a transparent conductive oxide layer. The barrier layers having different structures and different materials may be provided according to different types of solar cells.

[0054] In the present application, the solar cell 100 may be a bifacial cell or a back contact cell. When the solar cell 100 is a bifacial cell, for example, it may include but is not limited to a TOPCon cell, a heterojunction cell (HIT cell), and a bifacial hybrid cell. It is understood that when it is a bifacial cell, the barrier layer 20 and the electrode structure 30 of the present application may be provided on any one side or both sides of its cell body 10. When the solar cell 100 is a back contact cell, for example, it may include but is not limited to a TBC cell, an HBC cell (heterojunction back contact cell), and a hybrid back contact cell. Among them, in some examples, the back contact cell such as a TBC cell, an HBC cell, and a hybrid back contact cell may be designed as an interdigitated back contact cell (IBC cell). When the solar cell is a back contact cell, the barrier layer 20 and the electrode structure 30 of the present application may be provided on at least one of the P region and the N region of the cell body 10.

[0055] In the case where the solar cell 100 is a TOPCon cell, the cell body 10 includes a semiconductor substrate 101 and a tunneling layer (for example, a tunneling oxide layer), a doped polysilicon layer (equivalent to the doped semiconductor layer 102) and a dielectric layer 103 stacked in sequence on the semiconductor substrate 101, wherein the dielectric layer 103 has an opening, and the electrode structure 30 is correspondingly arranged in the opening. In the TOPCon cell, the stacked tunneling layer and the doped polysilicon layer together constitute a passivation contact structure, which can effectively reduce surface recombination and metal contact recombination. In some examples, the semiconductor substrate 101 is an n-type silicon substrate, and the doped semiconductor layer 102 is an n-type doped polysilicon layer. In this case, the barrier layer 20 disposed on the cell body 10 can be an integral structure, or can include a plurality of sub-barrier layers 201. When the barrier layer 20 is an integral structure, the barrier layer 20 can be a TCO layer; when it includes a plurality of sub-barrier layers 201, the barrier layer 20 can be a TCO layer or a metal layer.

[0056] In the case where the solar cell 100 is a HIT cell, the cell body 10 includes a semiconductor substrate 101 and two doped semiconductor layers 102 respectively disposed on two opposite surfaces of the semiconductor substrate 101, and the two doped semiconductor layers 102 have opposite doping types, that is, one is n-type doped and the other is p-type doped. At this time, the material of the doped semiconductor layer 102 can be one or more of doped amorphous silicon, doped microcrystalline silicon, and doped nanocrystalline silicon. The HIT cell also includes an intrinsic amorphous silicon layer disposed between the semiconductor substrate 101 and the doped semiconductor layer 102. The intrinsic amorphous silicon layer has an excellent passivation effect on the surface of the silicon substrate, which can greatly avoid the recombination of carriers and achieve a higher minority carrier lifetime and open circuit voltage. In this case, the barrier layer 20 disposed on the cell body 10 is an integrated structure, and the barrier layer 20 can be a TCO layer.

[0057] In the case where the solar cell 100 is a bifacial hybrid cell, the cell body 10 includes a semiconductor substrate 101, a tunneling layer (for example, a tunneling oxide layer), a doped polysilicon layer (equivalent to the first doped semiconductor layer 102) and a dielectric layer 103 stacked in sequence on the first surface of the semiconductor substrate 101, and an intrinsic amorphous silicon layer and a second doped semiconductor layer stacked in sequence on a second surface opposite to the first surface, wherein the material of the second doped semiconductor layer can be one or more of doped amorphous silicon, doped microcrystalline silicon, and doped nanocrystalline silicon; wherein the doped polysilicon layer and the second doped semiconductor layer have opposite conductivity types, that is, one is n-type doped and the other is p-type doped; wherein the tunneling layer and the doped polysilicon layer can be arranged in a local area on the first surface, or in the entire area on the first surface. The doped semiconductor layer can include at least one of the first doped semiconductor layer 102 and the second doped semiconductor layer. In this case, the barrier layers 20 disposed on both sides of the battery body 10 may be an integrated structure; or the barrier layer 20 on the side provided with the intrinsic amorphous silicon layer and the doped semiconductor layer 102 may be an integrated structure, while the barrier layer 20 on the side provided with the tunneling layer and the doped polysilicon layer includes a plurality of sub-barrier layers 201, and the sub-barrier layers 201 are disposed together with the electrode structure 30 corresponding to the opening 104 of the dielectric layer 103. When the barrier layer 20 is an integrated structure, the barrier layer 20 may be a TCO layer; when it includes a plurality of sub-barrier layers 201, the barrier layer 20 may be a TCO layer or a metal layer.

[0058] In the case where the solar cell 100 is an HBC cell, the cell body 10 includes a semiconductor substrate 101, the semiconductor substrate 101 includes a P region and an N region alternately arranged in sequence, the cell body 10 includes a first intrinsic amorphous silicon layer and a P-type doped semiconductor layer sequentially arranged in the P region, and a second intrinsic amorphous silicon layer and an N-type doped semiconductor layer sequentially arranged in the N region, and the doped semiconductor layer 102 includes at least one of a P-type doped semiconductor layer and an N-type doped semiconductor layer. The materials of the P-type doped semiconductor layer and the N-type doped semiconductor layer can be one or more of doped amorphous silicon, doped microcrystalline silicon, and doped nanocrystalline silicon. In some examples, the semiconductor substrate 101 also includes an overlapping region arranged between the P region and the N region, the first intrinsic amorphous silicon layer, the P-type doped semiconductor layer, the second intrinsic amorphous silicon layer, and the N-type doped semiconductor layer are sequentially stacked and arranged in the overlapping region, the second intrinsic amorphous silicon layer and the N-type doped semiconductor layer can be arranged on the first intrinsic amorphous silicon layer and the P-type doped semiconductor layer, or the first intrinsic amorphous silicon layer and the P-type doped semiconductor layer can be arranged on the second intrinsic amorphous silicon layer and the N-type doped semiconductor layer. Electrode structures 30 are provided in the P region and the N region, respectively. HBC batteries help to improve carrier lifetime and reduce surface recombination. In this case, the barrier layer 20 provided on the doped semiconductor layer 102 of the battery body 10 includes a plurality of sub-barrier layers 201, one sub-barrier layer 201 corresponds to one P region, or corresponds to one N region, wherein the plurality of sub-barrier layers 201 correspond one to one with the plurality of electrode structures 30, and the barrier layer 20 may be a TCO layer.

[0059] In the case where the solar cell 100 is a TBC cell, the cell body 10 includes a semiconductor substrate 101, and the semiconductor substrate 101 includes a P region and an N region alternately arranged in sequence; the cell body 10 includes a tunneling layer (for example, a tunneling oxide layer) and a P-type doped polysilicon layer arranged in sequence in the P region, and a tunneling layer and an N-type doped polysilicon layer arranged in sequence in the N region, and the doped semiconductor layer 102 includes at least one of a P-type doped polysilicon layer and an N-type doped polysilicon layer; the cell body 10 also includes a dielectric layer 103 arranged on the P-type doped polysilicon and the N-type doped semiconductor layer, and the sub-blocking layer 201 and the electrode structure 30 are arranged together corresponding to the opening 104 of the dielectric layer 103, and the sub-blocking layer 201 is in contact with the doped semiconductor layer 102. In some examples, the semiconductor substrate 101 also includes an isolation region arranged between the P region and the N region, and the isolation region can be, for example, an isolation groove. The electrode structure 30 is respectively arranged in the P region and the N region. In this case, the barrier layer 20 disposed on the doped semiconductor layer 102 of the battery body 10 includes a plurality of sub-barrier layers 201 , wherein the plurality of sub-barrier layers 201 correspond one-to-one to the plurality of electrode structures 30 , and the barrier layer 20 may be a metal layer or a TCO layer.

[0060] In the case where the solar cell 100 is a hybrid back contact cell, the cell body 10 includes a semiconductor substrate 101 and a tunnel passivation contact structure and a heterojunction contact structure alternately arranged on the semiconductor substrate 101, wherein the tunnel passivation contact structure includes a stacked tunneling layer (for example, a tunneling oxide layer) and a doped polysilicon layer (equivalent to a first doped semiconductor layer), the heterojunction contact structure includes a stacked intrinsic amorphous silicon layer and a second doped semiconductor layer, the doped semiconductor layer 102 includes at least one of a first doped semiconductor layer and a second doped semiconductor layer, wherein the material of the second doped semiconductor layer may be one or more of doped amorphous silicon, doped microcrystalline silicon, and doped nanocrystalline silicon; wherein the doped polysilicon layer and the second doped semiconductor layer have opposite conductivity types, that is, one is n-type doped and the other is p-type doped. In some examples, the heterojunction contact structure extends and overlaps a portion of the tunnel passivation contact structure. In this case, the barrier layer 20 disposed on the doped semiconductor layer 102 of the battery body 10 includes a plurality of sub-barrier layers 201 , wherein the plurality of sub-barrier layers 201 correspond one-to-one to the plurality of electrode structures 30 , and the barrier layer 20 may be a TCO layer.

[0061] It can be understood that n-type silicon substrate, n-type doping layer, or n-type doping refers to doping with dopants containing group V elements such as P, As, etc., which are used to provide electrons after doping. P-type silicon substrate, p-type doping layer, or p-type doping refers to doping with dopants containing group III elements such as B, Al, etc., which are used to provide holes after doping.

[0062] In the present application, the solar cell 100 may be any one of the above-mentioned cells.

[0063] In some embodiments, the material of the transparent conductive oxide layer includes one or more of indium tin oxide (ITO), indium tungsten oxide (IWO), and indium titanium oxide (ITiO). Of course, other materials may also be used, and this application does not further limit this. Providing a transparent conductive oxide layer is not only conducive to collecting carriers in the doped semiconductor layer 102, but also has a certain anti-reflection effect.

[0064] In some embodiments, the material of the metal layer includes one or more of nickel, silver, tin, and aluminum. Of course, other materials may also be used, and this application does not further limit this.

[0065] Continue to refer Figure 1, a plurality of electrode structures 30 are arranged on the barrier layer 20, and the electrode structure 30 includes an organic layer 301 and an electrode layer 302 which are sequentially stacked. Compared with the prior art in which the electrode layer is formed on the barrier layer 20 by screen printing, the organic layer 301 is additionally arranged between the barrier layer 20 and the electrode layer 302, which can increase the bonding force between the barrier layer 20 and the electrode layer 302 and improve the reliability of the solar cell 100. Figure 5 SEM images of the barrier layer 20 , the organic layer 301 , and the electrode layer 302 in a solar cell according to some embodiments of the present application are shown, wherein the barrier layer 20 is a TCO layer. Figure 6 SEM images of the barrier layer 20 , the organic layer 301 , and the electrode layer 302 in a solar cell according to some embodiments of the present application are shown, wherein the barrier layer 20 is a metal layer.

[0066] In the present application, the electrode layer 302 includes an organic carrier and first metal particles, that is, the electrode layer is a slurry layer. The organic carrier of the electrode layer 302 can be a commonly used organic material known in the art for forming a slurry, which generally includes, for example, resin, curing accelerator, and other additives such as dispersants, coupling agents, etc.; wherein the resin can be selected from epoxy resins such as glycidyl ether epoxy resins, glycidyl ester epoxy resins, alicyclic epoxy resins, etc., polyurethane resins, polyester resins, phenolic resins, phenoxy resins, and one or more combinations thereof; the curing accelerator is selected from amine curing accelerators, acid curing accelerators, and quaternary ammonium salt curing accelerators. For specific types, those skilled in the art can select as needed, and this application does not limit this. It can be understood that the above-mentioned organic materials are usually non-conductive, but they can be made conductive by modifying the above-mentioned organic materials or adding conductive fillers (such as graphene, carbon nanotubes, carbon black, nanometals and their oxides). The first metal particles filled in the organic carrier in the electrode layer 302 form a conductive network to achieve conductive properties. In some embodiments, the material of the first metal particles may include copper, silver, nickel, aluminum, alloys thereof, or any combination thereof, wherein the alloy may be copper-silver alloy, copper-nickel alloy, silver-nickel alloy, silver-aluminum alloy, etc. It is understood that the materials of the above-mentioned organic carrier and the materials of the first metal particles are only exemplary, and those skilled in the art may also use other materials to form the electrode layer 302, which is not further limited in this application. In some embodiments, the material of the electrode layer may be silver paste, copper paste, silver-coated copper paste, etc.

[0067] In some embodiments, the first metal particles may be at least one of spherical particles and flaky particles. Such first metal particles may form a conductive network in the electrode layer 302, which may improve the conductivity of the electrode layer 302 and the collection efficiency of carriers. Here, the size range of the spherical particles is 50nm to 1.5μm, for example, 50nm, 60nm, 100nm, 150nm, 200nm, 300nm, 500nm, 1μm, 1.5μm. The size of the spherical particles in this range can ensure that the electrode layer 302 has good conductivity. The size range of the flaky particles is 1μm to 6μm, for example, 1μm, 2μm, 3μm, 4μm, 5μm, 6μm. The size of the flaky particles in this range can ensure that the electrode layer 302 has good conductivity.

[0068] In some examples, the first metal particles include flaky particles, and the flaky particles include single-layer flaky particles. Since the flaky particles include single-layer flaky particles, the number of flaky particles dispersed in the electrode layer will be greater, which is more conducive to improving the conductivity of the electrode layer 302. Compared with multi-layer flaky particles, the surface of single-layer flaky particles is smoother.

[0069] In some other examples, the flake particles include multi-layer flake particles, that is, flake particles formed by stacking a plurality of flake layers. In this case, the resistance of the flake particles is smaller.

[0070] In some examples, the first metal particles include flaky particles, and the contour of the flaky particles is surrounded by a smooth curved surface. Here, the contour of the flaky particles may refer to the outer contour of the flaky particles observed at any viewing angle when detected under an electron microscope (e.g., a scanning electron microscope). Since the contour of the flaky particles is surrounded by a smooth curved surface, the uniformity of the first metal particles in the electrode layer can be improved, thereby improving the conductivity of the electrode layer.

[0071] It should be noted that the first metal particles may be formed by the accumulation of at least one of metal ions and metal atoms.

[0072] In the present application, the organic material of the organic layer 301 is the same as the organic material of the organic carrier of the electrode layer 302. Using the same organic material can make the combination between the organic layer 301 and the electrode layer 302 stronger, thereby improving the bonding force between the organic layer 301 and the electrode layer 302 and improving the reliability of the solar cell 100.

[0073] It is understandable that the organic layer 301 can be formed separately from the electrode layer 302, for example, the organic layer 301 is formed first, and then the electrode layer 302 is formed; the organic layer 301 can also be formed simultaneously with the electrode layer 302. In the case of simultaneous formation, in the process of forming the electrode layer 302, by controlling the process conditions such as the printing speed and temperature, the organic material in the electrode layer 302 can be formed between the electrode layer 302 and the barrier layer 20, thereby forming the organic layer 301, which not only simplifies the process, but also connects the organic material of the organic layer 301 with the organic material of the organic carrier of the electrode layer 302 to form an integrated structure, which is more conducive to increasing the bonding force between the electrode layer 302 and the barrier layer 20.

[0074] In some embodiments, the thickness of the organic layer 301 is 0.01nm-50nm, for example, the thickness of the organic layer 301 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 layer 301 is too small, the electrode layer 302 and the barrier layer 20 cannot be firmly combined together. If the thickness is too large, the body resistance of the organic layer 301 will be too large, affecting the collection of carriers, thereby affecting the photoelectric conversion efficiency of the solar cell 100. Controlling the thickness of the organic layer 301 within the above range can not only ensure that the organic layer 301 can firmly combine the electrode layer 302 and the barrier layer 20 together, but also the body resistance of the organic layer 301 will not be too large, so that the efficient collection of carriers can be ensured.

[0075] It is understood that the thickness of the organic layer 301 may be uniform or non-uniform. When the thickness of the organic layer is non-uniform, in this case, the thickness of the organic layer is 0.01nm-50nm, which means that the thickness of any position in the organic layer 301 is within the thickness range (0.01nm-50nm) of the organic layer 301. Of course, in some examples, it may also mean that the thickness of any position of the organic layer 301 is within the range (0.01nm-50nm) of the organic layer 301.

[0076] In order to achieve electrical connection between the electrode layer 302 and the blocking layer 20, ensure a low contact resistance between the electrode layer 302 and the blocking layer 20, and ensure a large bonding force between the electrode layer 302 and the blocking layer 20, in the present application, this can be achieved by adjusting the thickness, material, electrode layer 302, etc. of the organic layer 301, which is explained below with some examples.

[0077] In some embodiments, the thickness of at least one location in the organic layer 301 is 0.01nm-5nm, such as 0.01nm, 0.5nm, 1nm, 2nm, 3nm, 4nm, 5nm. In other embodiments, the thickness of at least one location in the organic layer is 0.01nm-10nm, such as 0.01nm, 0.5nm, 1nm, 2nm, 3nm, 4nm, 5nm, 6nm, 7nm, 8nm, 9nm, 10nm. It is understood that the thickness of one or more locations in the organic layer 301 may be within the range of 0.01nm-5nm, or within the range of 0.01nm-10nm; the thickness of any location in the organic layer 301 may be within the range of 0.01nm-5nm, or within the range of 0.01nm-10nm. The thinner organic layer 301 can achieve conductivity through the tunneling mechanism, so when the organic layer 301 itself is not conductive, the organic layer 301 of such thickness can still electrically connect the electrode layer 302 with the barrier layer 20. The organic material of the organic layer 301 is the same as the above-mentioned organic material of the electrode layer 302. Figure 7 FIG. 1 shows SEM images of the barrier layer 20, the electrode layer 302, and the organic layer 301 in the solar cell 100 according to some embodiments of the present application. Figure 7 It can be seen that the thickness of the organic layer 301 is about 3.5 nm. Since the thickness of the organic layer 301 is small, carriers can pass through the organic layer 301 through a tunneling mechanism to achieve electrical connection between the electrode layer 301 and the barrier layer 20. In this case, the organic material in the organic layer 301 may be conductive or non-conductive.

[0078] It can be understood that in some embodiments, the organic layer 301 itself has a conductive property, that is, is a conductive organic layer, so as to electrically connect the electrode layer 302 with the barrier layer 20. At this time, the thickness of the organic layer 301 is not limited.

[0079] In order to make the organic layer 301 itself have conductive properties, it can be achieved by at least one of the following two methods: on the one hand, the organic layer 301 can contain second metal particles, that is, the second metal particles in the organic layer 301 are filled in the organic material, and the conductive network is formed in the organic layer 301 by the second metal particles, so that the conductive property can be achieved. Here, the second metal particles can be formed by the accumulation of at least one of metal ions and metal atoms. On the other hand, the organic material of the organic layer 301 can be a conductive organic material, and the conductive property is achieved by using the conductive organic material. The organic material of the organic layer 301 is the same as the above-mentioned organic material of the electrode layer 302. Figure 8SEM images of the barrier layer 20 , the electrode layer 302 , and the organic layer 301 in the solar cell 100 according to some embodiments of the present application are shown, wherein the barrier layer 20 is a metal layer, and the organic layer 301 contains second metal particles.

[0080] In some embodiments, the particle size of the second metal particles is smaller than that of the first metal particles. In some embodiments, the second metal particles are nano-sized metal particles, which makes it easier for the metal particles to be dispersed in the organic layer 301. Optionally, the particle size of the second metal particles is 1nm-20nm, for example, 1nm, 3nm, 5nm, 10nm, 15nm, 20nm. Figure 8 It can also be seen in FIG. 3 that in some examples, the second metal particles contained in the conductive organic layer 301 are nano-scale metal particles. Optionally, the particle size of the second metal particles is less than 10 nm.

[0081] In some embodiments, the material of the second metal particles may be the same as or different from that of the first metal particles. In some embodiments, the material of the second metal particles may be copper, silver, nickel, aluminum, an alloy thereof, or any combination thereof, wherein the alloy may be a copper-silver alloy, a copper-nickel alloy, a silver-nickel alloy, a silver-aluminum alloy, etc. It is understood that the material of the second metal particles is only exemplary, and those skilled in the art may also use metal materials, which is not further limited in this application.

[0082] In some embodiments, such as Figure 6 As shown, the first metal particles in the electrode layer 302 pass through the organic layer 301 and contact the barrier layer 20 (for example, Figure 6 ), thereby achieving electrical connection between the electrode layer 302 and the blocking layer 301.

[0083] In order to ensure that the transmission resistance of carriers when passing through the organic layer 301 is not too large, and to ensure that the bonding force between the electrode layer 302 and the barrier layer 20 through the organic layer 301 is sufficient, in some examples, the organic layer 301 includes at least one conductive contact point within a range of 50 μm, and the thickness of the organic layer 301 at the conductive contact point is 0.01 nm-10 nm; or, the first metal particles in the electrode layer 302 at the conductive contact point pass through the organic layer 301 and contact the barrier layer 20.

[0084] Here, the organic layer 301 includes at least one conductive contact point within 50 μm, and may include at least one conductive contact point within 50 μm along the width direction of the electrode layer 302 or at least one conductive contact point within 50 μm along the length direction of the electrode layer 302 .

[0085] In addition, the organic layer 301 includes at least one conductive contact point within a range of 50 μm, and may include one conductive contact point or two or more conductive contact points.

[0086] In some embodiments, the width of the organic layer 301 is greater than or equal to the width of the electrode layer 302. By controlling any width of the organic layer 301 to be greater than or equal to any width of the electrode layer 302, it is possible to ensure that any position in the electrode layer 302 can be electrically connected to the barrier layer through the organic layer 310, further increasing the bonding force between the electrode structure and the barrier layer, thereby preventing the electrode structure from falling off.

[0087] In some embodiments, the projection area of ​​the organic layer 301 on the surface of the battery body 10 completely covers the projection area of ​​the electrode layer 302 on the surface of the battery body 10, that is, when the organic layer 301 and the electrode layer 302 are simultaneously projected onto the battery body 10, what can be seen is the projection area of ​​the organic layer 301. It can be understood that "complete coverage" includes two situations, one is that the projection area of ​​the organic layer 301 is larger than the projection area of ​​the electrode layer 302, and the other is that the projection area of ​​the organic layer 301 overlaps with the projection area of ​​the electrode layer 302. Here, reference can be made to the beneficial effect that the width of the organic layer 301 is greater than or equal to the width of the electrode layer 302, which will not be repeated here.

[0088] The present application also provides a photovoltaic assembly, including a plurality of cell strings, the cell strings including a plurality of solar cells and a plurality of interconnecting members, the interconnecting members being used to connect the plurality of solar cells in series; wherein the solar cell is any of the above-mentioned solar cells 100 of the present application.

[0089] In the present application, the features and effects described for the solar cell 100 of the present application are also applicable to the photovoltaic module of the present application and will not be described in detail here.

[0090] The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A solar cell, characterized in that: include: Battery body; A barrier layer, disposed on the battery body; A plurality of electrode structures are arranged on the barrier layer, and the electrode structures include an organic layer and an electrode layer stacked in sequence; The electrode layer includes an organic carrier and first metal particles, and the organic material of the organic layer is the same as the organic material of the organic carrier.

2. The solar cell according to claim 1, characterized in that The thickness of the organic layer is 0.01 nm-50 nm.

3. The solar cell according to claim 1, characterized in that The thickness of at least one location in the organic layer is 0.01 nm-5 nm; or, the thickness of at least one location in the organic layer is 0.01 nm-10 nm.

4. The solar cell according to claim 1, characterized in that The width of the organic layer is greater than or equal to the width of the electrode layer.

5. The solar cell according to claim 1, characterized in that: The projection area of ​​the organic layer on the battery body completely covers the projection area of ​​the electrode layer on the battery body.

6. The solar cell according to claim 1, characterized in that The first metal particles in the electrode layer pass through the organic layer to contact the barrier layer.

7. The solar cell according to claim 1, characterized in that The organic layer includes at least one conductive contact point within a range of 50 μm, and the thickness of the organic layer at the conductive contact point is 0.01 nm-10 nm; or, the first metal particles in the electrode layer at the conductive contact point pass through the organic layer and contact the barrier layer.

8. The solar cell according to claim 1, characterized in that The organic layer is a conductive organic layer.

9. The solar cell according to claim 8, characterized in that The organic layer contains second metal particles, and the particle size of the second metal particles is smaller than the particle size of the first metal particles; And / or, the organic material in the organic layer is a conductive organic material.

10. The solar cell according to claim 1, characterized in that The first metal particles include flaky particles, the flaky particles include single-layer flaky particles; and / or the contours of the flaky particles are surrounded by smooth curved surfaces.

11. The solar cell according to claim 1, characterized in that: The barrier layer is an integrated structure.

12. The solar cell according to claim 1, characterized in that The blocking layer includes a plurality of sub-blocking layers, wherein the plurality of sub-blocking layers correspond one-to-one to the plurality of electrode structures.

13. The solar cell according to claim 1, characterized in that The barrier layer is a metal layer or a transparent conductive oxide layer.

14. The solar cell according to any one of claims 1 to 13, characterized in that: The battery body comprises a semiconductor substrate and a doped semiconductor layer arranged on the semiconductor substrate, the barrier layer is in contact with the doped semiconductor layer, and the electrode structure is electrically connected to the doped semiconductor layer through the barrier layer.

15. The solar cell according to any one of claims 1 to 13, characterized in that: The battery body includes a semiconductor substrate and a doped semiconductor layer and a dielectric layer sequentially arranged on the semiconductor substrate. The dielectric layer has a plurality of openings, one of the openings corresponds to one electrode structure, the barrier layer passes through the opening and contacts the doped semiconductor layer, and the electrode structure is electrically connected to the doped semiconductor layer through the barrier layer.

16. A photovoltaic module, characterized in that: The invention comprises a plurality of battery strings, wherein the battery strings comprise a plurality of solar cells and a plurality of interconnectors, wherein the interconnectors are used to connect the plurality of solar cells in series; Wherein, the solar cell is the solar cell according to any one of claims 1-15.

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