Solar cell, photovoltaic module and photovoltaic system
By adopting a stacked TCO conductive film structure in HJT solar cells, and using the combination of columnar crystals and isometric crystals, the problem of insufficient conductivity of TCO thin films in HJT solar cells is solved, and more efficient light conversion efficiency and more stable performance are achieved.
Patent Information
- Application Number
- CN202421816237.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-29
- Publication Date
- 2025-05-09
- Estimated Expiration
- 2034-07-29
AI Technical Summary
In the existing HJT solar cells, the lateral conductivity of the amorphous passivation layer and the doped layer is poor, making it difficult to achieve lateral carrier transmission, resulting in difficulty in improving the performance of TCO films.
The TCO conductive film structure is adopted in a laminated arrangement. The first TCO conductive film layer adopts columnar crystals, the second TCO conductive film layer adopts columnar crystals in the electrode contact area, and the non-electrode contact area adopts isometric crystals to ensure the excellent conductivity of the conductive film in the vertical and transverse directions.
It effectively reduces resistance loss, improves the photo conversion efficiency of solar cells, and avoids TCO performance attenuation caused by humid and heat environment through excellent electrode adhesion.
Smart Images
Figure CN222852585U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of solar cells, and in particular to a solar cell, a photovoltaic module and a photovoltaic system. Background Art
[0002] With the development of the photovoltaic industry, heterojunction (HJT) solar cells have become a hot topic in the current photovoltaic industry. Compared with other high-efficiency solar cells, such as Topcon, PERC, etc., HJT cells require transparent conductive oxide (TCO) films to obtain sufficient carrier transmission. This is because in HJT solar cells, the lateral conductivity of the amorphous passivation layer and the amorphous / microcrystalline doping layer is poor, and it is difficult to achieve the demand for lateral carrier transmission. Due to its good optoelectronic properties, TCO films have good optical transmittance and excellent conductivity, so they are widely used in current HJT cells.
[0003] At present, the commonly used TCO types are mainly divided into In2O3, SnO2 and ZnO. Based on these three materials, Sn, Ti, Zr, Ga, W, F, Al and other elements are doped to achieve different TCO performance requirements. At present, for single-layer TCO films, its performance optimization has been relatively mature and perfect, and it is difficult to further improve the performance through conventional means. Therefore, how to improve the performance through the composite structure of multi-layer TCO has become a current research hotspot. Utility Model Content
[0004] The embodiments of the present application provide a solar cell, a photovoltaic module and a photovoltaic system to solve or alleviate at least one of the technical problems mentioned above.
[0005] In a first aspect, an embodiment of the present application provides a solar cell, the solar cell comprising a first TCO conductive film layer, a second TCO conductive film layer and a first electrode layer sequentially arranged on a surface of one side of a composite layer;
[0006] The crystal type of the first TCO conductive film layer is columnar crystal;
[0007] The second TCO conductive film layer includes an electrode contact area and a non-electrode contact area corresponding to the first electrode layer;
[0008] The crystal form of the electrode contact area is columnar crystal, and the crystal form of the non-electrode contact area is equiaxed crystal.
[0009] Optionally, the first TCO conductive film layer has a thickness of 5-50 nm.
[0010] Optionally, the average grain size of the columnar crystals used in the first TCO conductive film layer is 10-50 nm.
[0011] Optionally, the second TCO conductive film layer has a thickness of 5-50 nm.
[0012] Optionally, in the second TCO conductive film layer, the average grain size of the columnar crystals used in the electrode contact area is 5-50 nm, and the average grain size of the equiaxed crystals used in the non-electrode contact area is 50-100 nm.
[0013] Optionally, the first electrode layer is any one of a silver electrode layer, a copper electrode layer or a silver-clad copper electrode layer; the present application does not specifically limit the material of the first electrode layer, and those skilled in the art may adjust it according to actual needs.
[0014] Optionally, the solar cell further includes a third TCO film layer and a second electrode layer which are sequentially arranged on the other side surface of the composite layer.
[0015] Optionally, the third TCO film layer has a thickness of 50-100 nm.
[0016] Optionally, the second electrode layer is any one of a silver electrode layer, a copper electrode layer or a silver-clad copper electrode layer.
[0017] Optionally, along the direction from the first TCO conductive film layer to the second TCO conductive film layer, the composite layer includes a second doping layer, a second passivation layer, a base layer, a first passivation layer and a first doping layer which are stacked.
[0018] In a second aspect, an embodiment of the present application provides a photovoltaic component, wherein the photovoltaic component includes the solar cell described in the first aspect.
[0019] In a third aspect, an embodiment of the present application provides a photovoltaic system, wherein the photovoltaic system includes the photovoltaic component described in the second aspect.
[0020] The technical solution adopted in the embodiment of the present application may include the following advantages: when forming a solar cell, the TCO conductive film layer includes a first TCO conductive film layer and a second TCO conductive film layer which are stacked, the first TCO conductive film layer adopts columnar crystals, the electrode contact area corresponding to the first electrode layer in the second conductive film layer is columnar crystals, and the non-electrode contact area is equiaxed crystals, which can ensure that the TCO conductive film layer has excellent conductivity in both vertical and lateral directions and effectively reduce resistance loss; in addition, the electrode contact area adopts columnar crystals, which can increase the adhesion of the electrode layer on the TCO conductive film layer. Conversely, due to the excellent adhesion of the electrode layer on the TCO conductive film, it can also isolate the columnar crystals from water vapor, thereby avoiding the problem of TCO performance degradation caused by a humid and hot environment. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] In the accompanying drawings, unless otherwise specified, the same reference numerals throughout the multiple drawings represent the same or similar parts or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings only depict some embodiments disclosed in the present application and should not be regarded as limiting the scope of the present application.
[0022] Figure 1 : Schematic diagram of solar cell structure (the third TCO conductive film layer is a single-layer structure);
[0023] Figure 2 : Schematic diagram of solar cell structure (the third TCO conductive film layer is a stacked structure);
[0024] Figure 3 : Schematic diagram of composite layer structure;
[0025] Figure 4 : Schematic diagram of the HJT solar cell structure (the third TCO conductive film layer is a single-layer structure);
[0026] Figure 5 : Schematic diagram of the HJT solar cell structure (the third TCO conductive film layer is a stacked structure);
[0027] Description of reference numerals:
[0028] 1 is the first electrode layer; 2 is the second TCO conductive film layer; 3 is the first TCO conductive film layer; 4 is the composite layer; 5 is the third TCO conductive film layer; 6 is the second electrode layer;
[0029] 4-1 is the first doping layer; 4-2 is the first passivation layer; 4-3 is the base layer; 4-4 is the second passivation layer; 4-5 is the second doping layer. DETAILED DESCRIPTION
[0030] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings. In the accompanying drawings, for clarity, the sizes of layers, regions, elements and their relative sizes may be exaggerated. Wherein the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The embodiments described below are exemplary and are only used to explain the present application, and cannot be understood as limitations on the present application. It should be noted that, in the absence of conflict, the embodiments in the present application and the features in the embodiments can be combined with each other.
[0031] It should be understood that when an element or layer is referred to as "on ...", "adjacent to ...", "connected to" or "coupled to" other elements or layers, it can be directly on, adjacent to, connected to or coupled to other elements or layers, or there can be intervening elements or layers. On the contrary, when an element is referred to as "directly on ...", "directly adjacent to ...", "directly connected to" or "directly coupled to" other elements or layers, there is no intervening element or layer. It should be understood that although the terms first, second, third, etc. can be used to describe various elements, components, regions, layers and / or parts, these elements, components, regions, layers and / or parts should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or part from another element, component, region, layer or part. Therefore, without departing from the teachings of the present disclosure, the first element, component, region, layer or part discussed below can be represented as the second element, component, region, layer or part. And when the second element, component, region, layer or part is discussed, it does not mean that the present disclosure necessarily has the first element, component, region, layer or part.
[0032] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.
[0033] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein, for example. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.
[0034] In the present application, when it comes to a numerical interval (i.e., a numerical range), unless otherwise specified, the distribution of the optional numerical values in the numerical interval is considered to be continuous, and includes the two numerical endpoints (i.e., the minimum and maximum values) of the numerical interval, and each numerical value between the two numerical endpoints. Unless otherwise specified, when the numerical interval only refers to an integer in the numerical interval, including the two endpoint integers of the numerical range, and each integer between the two endpoints, is equivalent to directly listing each integer. When multiple numerical ranges are provided to describe features or characteristics, these numerical ranges can be merged. In other words, unless otherwise specified, the numerical range disclosed in the present application should be understood to include any and all sub-ranges included therein. The "numerical value" in the numerical interval can be any quantitative value, such as a number, a percentage, a ratio, etc. "Numerical interval" allows for broadly including quantitative intervals such as percentage intervals, ratio intervals, and ratio intervals.
[0035] The embodiment of the present application provides a solar cell, comprising a first TCO conductive film layer, a second TCO conductive film layer and a first electrode layer sequentially arranged on a surface of one side of a composite layer;
[0036] The crystal type of the first TCO conductive film layer is columnar crystal;
[0037] The second TCO conductive film layer includes an electrode contact area and a non-electrode contact area corresponding to the first electrode layer;
[0038] The crystal form of the electrode contact area is columnar crystal, and the crystal form of the non-electrode contact area is equiaxed crystal.
[0039] In some embodiments, the grains of the columnar crystals present a columnar growth pattern, and the number of grain boundaries parallel or approximately parallel to the surface of the silicon wafer is much less than the number of grain boundaries perpendicular or approximately perpendicular to the surface of the silicon wafer.
[0040] In some embodiments, the grains of the equiaxed crystals grow in a block-like pattern, and the number of grain boundaries parallel or approximately parallel to the surface of the silicon wafer is similar to the number of grain boundaries perpendicular or approximately perpendicular to the surface of the silicon wafer.
[0041] When forming a solar cell, the TCO conductive film layer adopts a first TCO conductive film layer and a second TCO conductive film layer which are stacked. The first TCO conductive film layer adopts columnar crystals, and the electrode contact area corresponding to the first electrode layer in the second conductive film layer is columnar crystals, and the non-electrode contact area is equiaxed crystals, which can ensure that the TCO conductive film layer has excellent conductivity in both vertical and lateral directions and effectively reduce resistance loss. In addition, the electrode contact area adopts columnar crystals, which can increase the adhesion of the electrode layer on the TCO conductive film layer. Conversely, due to the excellent adhesion of the electrode layer on the TCO conductive film, it can also isolate the columnar crystals from water vapor, thereby avoiding the problem of TCO performance degradation caused by a humid and hot environment.
[0042] In some embodiments, the materials of the first TCO conductive film layer and the second TCO conductive film layer mainly include In2O3, SnO2 and ZnO. Based on these three materials, multiple elements such as Sn, Ti, Zr, Ga, W, F, Al, etc. are doped to achieve different TCO performance requirements. The embodiments of the present application do not limit the specific material types of TCO, but only consider the crystal structure of TCO. Different TCO materials can form equiaxed crystals and columnar crystals of TCO by adjusting the deposition parameters during the deposition process. The embodiments of the present application only consider utilizing the conductivity and physical properties of equiaxed crystals and columnar crystals in different directions to improve battery performance.
[0043] In some embodiments, the thickness of the first TCO conductive film layer is 5-50 nm (exemplarily, the thickness of the first TCO conductive film layer is 5 nm, 10 nm, 15 nm, 20 nm, 25 nm, 30 nm, 35 nm, 40 nm, 45 nm or 50 nm, etc.).
[0044] In some embodiments, the average grain size of the columnar crystals used in the first TCO conductive film layer is 10-50 nm (exemplarily, the average grain size is 10 nm, 15 nm, 20 nm, 25 nm, 30 nm, 35 nm, 40 nm, 45 nm or 50 nm, etc.).
[0045] In some embodiments, the thickness of the second TCO conductive film layer is 5-50 nm (exemplarily, the thickness of the second TCO conductive film layer is 5 nm, 10 nm, 15 nm, 20 nm, 25 nm, 30 nm, 35 nm, 40 nm, 45 nm or 50 nm, etc.).
[0046] In some embodiments, in the second TCO conductive film layer, the average grain size of the columnar crystals used in the electrode contact area is 5-50nm (exemplarily, the average grain size is 5nm, 10nm, 15nm, 20nm, 25nm, 30nm, 35nm, 40nm, 45nm or 50nm, etc.), and the average grain size of the equiaxed crystals used in the non-electrode contact area is 50-100nm (exemplarily, the average grain size is 50nm, 60nm, 70nm, 80nm, 90nm, 100nm, etc.).
[0047] In some embodiments, the first electrode layer is any one of a silver electrode layer, a copper electrode layer or a silver-coated copper electrode layer. The present application embodiment does not specifically limit the material of the first electrode layer, and those skilled in the art can adjust it according to actual needs.
[0048] In some embodiments, the solar cell further includes a third TCO film layer and a second electrode layer sequentially disposed on the other side surface of the composite layer.
[0049] In some embodiments, the thickness of the third TCO film layer is 50-100 nm (for example, the thickness of the third TCO film layer is 50 nm, 60 nm, 70 nm, 80 nm, 90 nm, 100 nm, etc.).
[0050] In some embodiments, the third TCO film layer may be a columnar crystal, or may be a structure in which the first TCO conductive film layer and the second TCO conductive film layer are stacked. When a stacked structure is adopted, the material and thickness of the stacked structure are consistent with those of the first TCO conductive film layer and the second TCO conductive film layer; wherein the film layer using columnar crystal material is connected to the substrate layer, and the film layer using columnar crystal and equiaxed crystal is connected to the second electrode layer.
[0051] In some embodiments, the second electrode layer is any one of a silver electrode layer, a copper electrode layer or a silver-coated copper electrode layer. The present application embodiment does not specifically limit the material of the second electrode layer, and those skilled in the art can adjust it according to actual needs.
[0052] In some embodiments, when the third TOC conductive film layer is a single-layer structure, the solar cell structure is as follows: Figure 1 As shown, it includes a first electrode layer 1, a second TCO conductive film layer 2, a first TCO conductive film layer 3, a composite layer 4, a third TOC conductive film layer 5 and a second electrode layer 6 which are stacked in sequence from top to bottom.
[0053] In some embodiments, when the third TOC conductive film layer is a stacked structure, it is arranged to be the same as the TOC conductive film layer on the other side of the composite layer. The solar cell structure is as follows: Figure 2 As shown, it includes a first electrode layer 1, a second TCO conductive film layer 2, a first TCO conductive film layer 3, a composite layer 4, a first TCO conductive film layer 3, a second TCO conductive film layer 2 and a second electrode layer 6 which are stacked in sequence from top to bottom.
[0054] In some embodiments, along the direction from the first TCO conductive film layer to the second TCO conductive film layer, such as Figure 3 As shown, the composite layer includes a second doping layer 4-5, a second passivation layer 4-4, a base layer 4-3, a first passivation layer 4-2 and a first doping layer 4-1 which are stacked.
[0055] When the composite layer includes a second doping layer, a second passivation layer, a base layer, a first passivation layer, and a first doping layer that are stacked, the solar cell is a HJT (heterojunction) solar cell; in the HJT solar cell, a stacked TCO conductive film layer is used, which has excellent lateral and vertical conductivity while ensuring good transmittance, effectively reduces resistance loss, has good adhesion to the electrode, and can avoid isolation from water vapor, thereby avoiding the problem of TCO performance attenuation caused by a humid and hot environment.
[0056] When the solar cell is a HJT solar cell:
[0057] The material of the first doping layer is a stack of one or more of N-type or P-type doped amorphous / nanocrystalline / microcrystalline silicon, amorphous / nanocrystalline / microcrystalline silicon oxygen, and amorphous / nanocrystalline / microcrystalline silicon carbide, with a thickness of 5-50nm (exemplarily, the thickness is 5nm, 10nm, 15nm, 20nm, 25nm, 30nm, 35nm, 40nm, 45nm, 50nm, etc.);
[0058] The material of the first passivation layer is intrinsic amorphous silicon, and the thickness is 3-30 nm (exemplarily, the thickness is 3 nm, 5 nm, 10 nm, 15 nm, 20 nm, 25 nm, 30 nm, etc.);
[0059] The substrate layer is an N-type or P-type doped silicon wafer;
[0060] The material of the second passivation layer is intrinsic amorphous silicon, and the thickness is 3-30 nm (exemplarily, the thickness is 3 nm, 5 nm, 10 nm, 15 nm, 20 nm, 25 nm, 30 nm, etc.);
[0061] The material of the second doping layer is a stack of one or more of N-type or P-type doped amorphous / nanocrystalline / microcrystalline silicon, amorphous / nanocrystalline / microcrystalline silicon oxygen, amorphous / nanocrystalline / microcrystalline silicon carbide, and the second doping layer is different from the doping type of the first doping layer, and has a thickness of 5-50nm (exemplarily, the thickness is 5nm, 10nm, 15nm, 20nm, 25nm, 30nm, 35nm, 40nm, 45nm, 50nm, etc.).
[0062] In some embodiments, a method for preparing a HJT solar cell includes:
[0063] S1, performing texturing and cleaning on a silicon wafer with N-type or P-type doping;
[0064] S2, depositing a first passivation layer and a second passivation layer on the first surface and the opposite second surface of the silicon wafer respectively;
[0065] S3, depositing a first doping layer on the first passivation layer, and doping a second doping layer on the second passivation layer;
[0066] S4, depositing a first TCO conductive film layer on the first doping layer, wherein the first TCO conductive film layer is a columnar crystal;
[0067] S5, depositing a second TCO conductive film layer on the first TCO conductive film layer, wherein the second TCO conductive film layer is patterned to deposit columnar crystals below the gate line and equiaxed crystals at other locations;
[0068] S6, depositing a third TCO conductive film layer on the second doped layer;
[0069] S7, preparing gate lines on the columnar crystals of the second TCO conductive film layer to form a first electrode layer;
[0070] S8. Prepare gate lines on the third TCO conductive film layer to form a second electrode layer.
[0071] In some embodiments, the deposition method includes vacuum evaporation, magnetron sputtering, chemical vapor deposition or atomic layer deposition.
[0072] In some embodiments, the electrode is formed by laser transfer, thermal evaporation, vacuum evaporation, magnetron sputtering, atomic layer deposition, 3D printing, screen printing, or inkjet printing.
[0073] The following specific examples further illustrate the present application, but should not be construed as limiting the present application. Without departing from the spirit and substance of the present application, modifications or replacements made to the methods, steps or conditions of the present application are within the scope of the present application.
[0074] [Example 1]
[0075] This embodiment provides a HJT solar cell, such as Figure 4 As shown, from top to bottom, it includes a first electrode layer 1, a second TCO conductive film layer 2, a first TCO conductive film layer 3, a first doping layer 4-1, a first passivation layer 4-2, a base layer 4-3, a second passivation layer 4-4, a second doping layer 4-5, a third TCO conductive film layer 5 and a second electrode layer 6 which are stacked in sequence.
[0076] Among them, the first passivation layer is an N-side intrinsic passivation layer, which consists of three sub-layers, all of which are made of intrinsic amorphous silicon, with thicknesses of 0.8nm, 0.8nm, and 5nm respectively;
[0077] The second passivation layer is a P-plane intrinsic passivation layer, which consists of three sub-layers, all made of intrinsic amorphous silicon, with thicknesses of 1nm, 1.5nm, and 6nm respectively;
[0078] The first doped layer is an N-face doped layer, which consists of four sublayers, namely a low-oxygen seed layer, an oxygen-containing seed layer, an N-doped layer main layer, and an N-doped layer contact layer. The low-oxygen seed layer is 0.8 nm thick, the oxygen-containing seed layer is 0.8 nm thick, the N-doped layer main layer is 21.4 nm thick, and the N-contact layer is 2 nm thick.
[0079] The second doped layer is a P-face doped layer, which consists of three sub-layers, namely a seed layer, a P-doped layer main layer, and a P-doped layer contact layer. The thickness of the seed layer is 1.5 nm, the thickness of the P-doped layer contact layer is 25 nm, and the thickness of the P-doped layer contact layer is 3 nm.
[0080] The first TCO conductive film layer is columnar crystal with a thickness of 30nm and an average grain size of 30nm;
[0081] The second TCO conductive film layer is columnar crystals below the gate electrode, and the rest is equiaxed crystals, with a thickness of 38nm, an average grain size of 30nm for the columnar crystals, and an average grain size of 100nm for the equiaxed crystals;
[0082] The third TCO conductive film layer is columnar crystals with a thickness of 77 nm and an average grain size of 30 nm.
[0083] The preparation method of HJT is the same as the conventional preparation method, namely, comprising:
[0084] (1) Before coating, the 100-crystalline N-type single-crystal silicon deposition needs to be cleaned and damaged, textured to form a pyramid surface of uniform size, RCA (chemical standard process) cleaning to remove surface organic matter and metal ions, smooth surface pyramids, and hydrofluoric acid to remove the oxide layer;
[0085] (2) preparing a first passivation layer and a second passivation layer on both sides of the silicon wafer by plasma chemical vapor deposition;
[0086] (3) depositing a first doped layer and a second doped layer on the surfaces of the first passivation layer and the second passivation layer respectively by plasma chemical vapor deposition;
[0087] (4) forming a first TCO conductive film layer and a second TCO conductive film layer on the surface of the first doped layer, and forming a third TCO conductive film layer on the surface of the second doped layer;
[0088] (5) The gate electrode is prepared by screen printing, laser transfer, and copper electroplating, and then cured and annealed to form a HJT battery.
[0089] in:
[0090] The size of the velvet pyramid is 1-3 microns, and the velvet crystal phase is 111 crystal phase;
[0091] The deposition pressure of columnar crystals is 0.3Pa, and the power density is 4KW / m, while the deposition pressure of equiaxed crystals is 1.0Pa, and the power density is 6KW / m.
[0092] [Example 2]
[0093] The difference from Example 1 is that the thickness of the first TCO conductive film layer is 5nm, the average nanoparticle size of the columnar crystals used is 10nm, the thickness of the second TCO conductive film layer is 5nm, the average nanoparticle size of the columnar crystals used in the electrode contact area is 5nm, and the average nanoparticle size of the equiaxed crystals used in the non-electrode contact area is 50nm.
[0094] [Example 3]
[0095] The difference from Example 1 is that the thickness of the first TCO conductive film layer is 50nm, the average nanoparticle size of the columnar crystals used is 50nm, the thickness of the second TCO conductive film layer is 50nm, the average nanoparticle size of the columnar crystals used in the electrode contact area is 50nm, and the average nanoparticle size of the equiaxed crystals used in the non-electrode contact area is 100nm.
[0096] [Comparative Example 1]
[0097] The difference from Example 1 lies in the arrangement of the TCO conductive film layer, wherein the second TCO conductive film layer is all equiaxed crystal.
[0098] The HJT solar cells obtained in Examples 1-3 and Comparative Example 1 were tested using a simulated light source system, and the relevant performance test results were normalized. The results are shown in Table 1.
[0099] Table 1 Performance test of HJT solar cells obtained in Examples 1-3 and Comparative Example 1
[0100] Battery Isc(A) Voc(V) FF(%) Eta(%) Rs(Ω) pFF(%) Example 1 1.00273 0.99984427 1.00723 1.009821345 0.39254 0.999978508 Example 2 0.99992 0.999831187 1.00146 1.001208707 0.82703 0.999516681 Example 3 1.00009 0.999463559 1.00189 1.00143781 0.76155 0.999135269 Comparative Example 1 1.00000 1 1.00000 1 1.00000 1
[0101] By comparing Example 1 and Comparative Example 1, it can be seen that when the TCO conductive film layer adopts the conductive film layer with a specific structure of the embodiment of the present application, it can ensure that the TCO conductive film layer has excellent conductivity in both the vertical and lateral directions, effectively reduce resistance losses, and thus improve the light conversion efficiency of the solar cell.
[0102] [Example 4]
[0103] This embodiment provides a HJT solar cell, such as Figure 5As shown, from top to bottom, it includes a first electrode layer 1, a second TCO conductive film layer 2, a first TCO conductive film layer 3, a first doping layer 4-1, a first passivation layer 4-2, a base layer 4-3, a second passivation layer 4-4, a second doping layer 4-5, a first TCO conductive film layer 3, a second TCO conductive film layer 2 and a second electrode layer 6 which are stacked in sequence.
[0104] The preparation method of Example 4 is similar to that of Example 1.
[0105] The solar cell obtained in Example 4 was subjected to a performance test, and the HJT solar cells obtained in Example 4 and Comparative Example 1 were tested using a simulated light source system, and the relevant performance test results were normalized, and the results are shown in Table 2.
[0106] Table 2 Performance test of HJT solar cells obtained in Example 4 and Comparative Example 1
[0107] Battery Isc(A) Voc(V) FF(%) Eta(%) Rs(Ω) pFF(%) Example 2 1.00388 1.000055978 1.00774 1.009060063 0.54044 1.002563916 Comparative Example 1 1.00000 1 1.00000 1 1.00000 1
[0108] By comparing Example 4 with Comparative Example 1, it can be seen that when the TCO conductive film layer adopts the conductive film layer with a specific structure of the present application, it can ensure that the TCO conductive film layer has excellent conductivity in both the vertical and lateral directions, effectively reducing resistance losses, thereby improving the light conversion efficiency of solar cells.
[0109] The embodiment of the present application provides a photovoltaic assembly (not shown), comprising the solar cell as described above. As an example, the photovoltaic group comprises at least one battery string, the battery string comprises at least two HJT solar cells of any embodiment, and adjacent HJT solar cells can be connected together by series welding.
[0110] The embodiment of the present application can provide a photovoltaic system, including the photovoltaic components in the above embodiment. The advantages of the above photovoltaic components are also possessed by the photovoltaic system, which will not be repeated here. The above photovoltaic system has a wide range of applications, not only limited to photovoltaic power stations, such as ground power stations, rooftop power stations and water power stations, but also includes various equipment and devices that use solar energy to generate electricity, such as user solar power supplies, solar street lights, solar cars and solar buildings. Of course, it can be understood that the application scenarios of the photovoltaic system are not limited to this, that is to say, the photovoltaic system can be used in all fields where solar energy is required for power generation. Taking the photovoltaic power generation system network as an example, the photovoltaic system may include a photovoltaic array, a junction box and an inverter. The photovoltaic array may be an array combination of multiple photovoltaic components. For example, multiple photovoltaic components can form multiple photovoltaic arrays. The photovoltaic array is connected to the junction box. The junction box can converge the current generated by the photovoltaic array. The converged current flows through the inverter and is converted into the alternating current required by the mains power grid and then connected to the mains network to realize solar power supply.
[0111] It should be noted that the terms "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc. are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. The orientation words "inside" and "outside" refer to the inside and outside relative to the outline of each component itself. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Therefore, the exemplary term "above..." can include both "above..." and "below..." orientations. The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used here are interpreted accordingly.
[0112] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein, for example. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.
[0113] It should also be noted that "one embodiment", "another embodiment", "embodiment", etc. mentioned in this application refer to the specific features, structures or characteristics described in conjunction with the embodiment included in at least one embodiment generally described in this application. The same expression appearing in multiple places in the specification does not necessarily refer to the same embodiment. Further, when describing a specific feature, structure or characteristic in conjunction with any embodiment, it is claimed that the realization of such feature, structure or characteristic in conjunction with other embodiments also falls within the scope of this application.
[0114] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.
[0115] It should also be noted that the above are only preferred embodiments of the present application, and the patent protection scope of the present application is not limited thereto. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.
Claims
1. A solar cell, characterized in that: The solar cell comprises a first TCO conductive film layer, a second TCO conductive film layer and a first electrode layer which are sequentially arranged on a surface of one side of the composite layer; The crystal type of the first TCO conductive film layer is columnar crystal; The second TCO conductive film layer includes an electrode contact area and a non-electrode contact area corresponding to the first electrode layer; The crystal form of the electrode contact area is columnar crystal, and the crystal form of the non-electrode contact area is equiaxed crystal.
2. The solar cell according to claim 1, characterized in that The thickness of the first TCO conductive film layer is 5-50nm; The average grain size of the columnar crystals used in the first TCO conductive film layer is 10-50 nm.
3. The solar cell according to claim 1, characterized in that The thickness of the second TCO conductive film layer is 5-50nm; In the second TCO conductive film layer, the average grain size of the columnar crystals used in the electrode contact area is 5-50 nm, and the average grain size of the equiaxed crystals used in the non-electrode contact area is 50-100 nm.
4. The solar cell according to claim 1, characterized in that The first electrode layer is any one of a silver electrode layer, a copper electrode layer or a silver-coated copper electrode layer.
5. The solar cell according to claim 1, characterized in that: The solar cell further includes a third TCO film layer and a second electrode layer which are sequentially arranged on the other side surface of the composite layer.
6. The solar cell according to claim 5, characterized in that The thickness of the third TCO film layer is 50-100 nm.
7. The solar cell according to claim 5, characterized in that: The second electrode layer is any one of a silver electrode layer, a copper electrode layer or a silver-clad copper electrode layer.
8. The solar cell according to any one of claims 1 to 7, characterized in that: Along the direction from the first TCO conductive film layer to the second TCO conductive film layer, the composite layer includes a second doping layer, a second passivation layer, a base layer, a first passivation layer and a first doping layer which are stacked.
9. A photovoltaic module, characterized in that: The photovoltaic module comprises the solar cell according to any one of claims 1 to 8.
10. A photovoltaic system, characterized in that: The photovoltaic system comprises the photovoltaic module according to claim 9.