Crystalline silicon solar cell and photovoltaic module
By stacking hydrogen isolation layers on the front of the silicon nitride and silicon oxynitride layers, the problem of poor bonding effect between hydrogen atoms and suspended bonds during high-temperature sintering is solved, a more thorough passivation effect is achieved, and crystalline silicon solar energy is improved Battery performance.
Patent Information
- Application Number
- CN202411250742.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-06
- Publication Date
- 2024-12-17
AI Technical Summary
During the high-temperature sintering process of existing crystalline silicon solar cells, the effect of hydrogen atoms on the hanging bonds on the surface of the silicon wafer is poor, resulting in a degradation of performance.
A hydrogen isolation layer is stacked on the front surfaces of the silicon nitride layer and the silicon oxynitride layer to physically isolate hydrogen to prevent it from diffusion, ensuring that the hydrogen recombines with the hanging bond, thereby improving the passivation effect.
It effectively avoids hydrogen diffusion, enhances the passivation effect of hanging bonds, and improves the photoelectric conversion efficiency of crystalline silicon solar cells.
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Figure CN119153546A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of crystalline silicon solar cells, and in particular to a crystalline silicon solar cell and a photovoltaic module. Background Art
[0002] In crystalline silicon solar cells, since silicon wafers are obtained by slicing, dangling bonds will be generated on the surface of the silicon wafers. The dangling bonds are easy to recombine with the carriers inside the battery, which affects the performance of the crystalline silicon solar cell.
[0003] At present, crystalline silicon solar cells use aluminum oxide, silicon oxynitride and silicon oxide stacks in which hydrogen atoms released during high-temperature sintering combine with dangling bonds on the surface of silicon wafers to achieve chemical passivation. However, after sintering at a high temperature of 800°C, hydrogen atoms in silicon nitride and silicon oxynitride are more likely to be released from the surface of the passivation film in the form of hydrogen gas, rather than diffusing to the surface of the silicon wafer to passivate dangling bonds. Therefore, the current passivation method is difficult to achieve the ideal passivation level.
[0004] It should be noted that the above content is not necessarily prior art, nor is it intended to limit the scope of patent protection of this application. Summary of the invention
[0005] The embodiments of the present application provide a crystalline silicon solar cell and a photovoltaic module to solve or alleviate one or more of the technical problems mentioned above.
[0006] A first aspect of an embodiment of the present application provides a crystalline silicon solar cell, comprising:
[0007] Silicon substrate;
[0008] A first passivation layer, a silicon nitride layer and a silicon oxynitride layer, wherein the first passivation layer, the silicon nitride layer and the silicon oxynitride layer are sequentially stacked on the front surface of the silicon substrate;
[0009] A hydrogen isolation layer, the hydrogen isolation layer is stacked on the front side of the silicon oxynitride layer; the porosity of the hydrogen isolation layer is smaller than the particle diameter of hydrogen molecules and larger than the particle diameter of hydrogen atoms;
[0010] The second passivation layer is stacked on a side of the hydrogen isolation layer away from the silicon substrate.
[0011] In one embodiment, the hydrogen isolation layer is deposited by atomic deposition.
[0012] In one embodiment, the hydrogen barrier layer is one of an aluminum oxide layer, a magnesium oxide layer, a magnesium fluoride layer and a zinc oxide layer.
[0013] In one embodiment, the porosity of the hydrogen barrier layer is 0.1-0.2 nm.
[0014] In one embodiment, the refractive indices of the first passivation layer, the silicon nitride layer, the silicon oxynitride layer, the hydrogen barrier layer, and the second passivation layer decrease in sequence.
[0015] In one embodiment, the hydrogen barrier layer has a thickness of 5-30 nm and a refractive index of 1.6-1.7.
[0016] In one embodiment, the thickness of the hydrogen barrier layer is greater than or equal to the thickness of the first passivation layer.
[0017] In one embodiment, the first passivation layer includes an aluminum oxide layer.
[0018] In one embodiment, the silicon nitride layer includes at least one silicon nitride film layer, and the at least one silicon nitride film layer is stacked in sequence between the first passivation layer and the silicon nitride oxide layer; the thickness of the silicon nitride film layer is 10-20nm, and the refractive index of the at least one silicon nitride film layer decreases layer by layer in a direction away from the silicon substrate, and the refractive index of the silicon nitride film layer is 1.9 to 2.3.
[0019] In one embodiment, the silicon oxynitride layer includes at least one silicon oxynitride film layer, and the at least one silicon oxynitride film layer is stacked in sequence between the silicon nitride layer and the hydrogen isolation layer; the thickness of the silicon oxynitride film layer is 10-20nm, and the refractive index of the at least one silicon oxynitride film layer decreases layer by layer in a direction away from the silicon substrate, and the refractive index of the silicon oxynitride film layer is 1.7 to 1.9.
[0020] In one embodiment, the second passivation layer includes at least one silicon oxide layer, which is sequentially stacked on the front side of the hydrogen isolation layer, the thickness of the silicon oxide layer on one side is 10-20nm, and the refractive index of the at least one silicon oxide layer decreases layer by layer in a direction away from the silicon substrate, and the refractive index of the silicon oxide layer is 1.5 to 1.6.
[0021] In one embodiment, the total thickness of the first passivation layer, the silicon nitride layer, the silicon oxynitride layer, the hydrogen isolation layer, and the second passivation layer is 50-150 nm.
[0022] A second aspect of the embodiments of the present application provides a photovoltaic module, which includes a plurality of solar cells connected in series and / or in parallel; wherein the crystalline silicon solar cell is the crystalline silicon solar cell of any one of the implementation aspects of the above embodiments.
[0023] The embodiment of the present application realizes hydrogen isolation in a physical sense by stacking a hydrogen isolation layer on the front side of the silicon nitride layer and the silicon oxynitride layer, isolating the hydrogen between the hydrogen isolation layer and the silicon substrate. Even under high-temperature sintering, it will not diffuse out, thereby ensuring the hydrogen content inside the battery and ensuring the passivation effect of the dangling bonds. BRIEF DESCRIPTION OF THE DRAWINGS
[0024] 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.
[0025] Figure 1 A schematic diagram of the front film structure of a crystalline silicon solar cell according to an embodiment of the present application is shown. DETAILED DESCRIPTION
[0026] 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. 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 with reference to the accompanying drawings 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 the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.
[0027] 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.
[0028] 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.
[0029] 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.
[0030] 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, it includes the two endpoint integers of the numerical range, and each integer between the two endpoints, which 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.
[0031] Hereinafter, exemplary embodiments according to the present application will be described in more detail with reference to the accompanying drawings. It should be noted that these exemplary embodiments can be implemented in many different forms and should not be construed as being limited to the embodiments described herein.
[0032] The embodiment of the present application provides a crystalline silicon solar cell, which is different from the current crystalline silicon solar cells in that the front film layer structure of the silicon substrate 1 is different. Figure 1The schematic diagram of the front film structure of the crystalline silicon solar cell according to the embodiment of the present application is shown. Figure 1 As shown, the crystalline silicon solar cell comprises: a silicon substrate 1. A first passivation layer 2, a silicon nitride layer 3, a silicon oxynitride layer 4, a hydrogen isolation layer 5 and a second passivation layer 6 are sequentially stacked on the front side of the silicon substrate 1. The porosity of the hydrogen isolation layer 5 is smaller than the particle diameter of the hydrogen molecule and larger than the particle diameter of the hydrogen atom.
[0033] The crystalline silicon solar cell provided in the embodiment of the present application is provided with a hydrogen isolation layer 5 on the front side of the silicon substrate 1. The hydrogen isolation layer 5 can be understood as any film layer structure with a porosity smaller than the particle diameter of hydrogen molecules and larger than the particle diameter of hydrogen atoms. The porosity is smaller than the particle diameter of hydrogen molecules and larger than the particle diameter of hydrogen atoms, so that hydrogen atoms can pass through the film layer, but hydrogen cannot pass through the film layer.
[0034] In the crystalline silicon solar cell provided in the embodiment of the present application, the silicon nitride layer 3 and the silicon oxynitride layer 4 will generate a large amount of hydrogen atoms and hydrogen gas after sintering. By stacking a hydrogen isolation layer 5 on the front side of the silicon nitride layer 3 and the silicon oxynitride layer 4, hydrogen atoms will be released from the hydrogen isolation layer 5, and the hydrogen gas will be retained because its particle diameter is greater than the porosity of the hydrogen isolation layer 5. The retained hydrogen gas can recombine with the dangling bonds on the surface of the silicon substrate 1, reducing the chance of carriers recombination with the dangling bonds, thereby promoting the movement of carriers inside the battery and improving the photoelectric conversion efficiency of the crystalline silicon solar cell.
[0035] In the embodiment of the present application, the silicon nitride layer 3 and the silicon oxynitride layer 4 that easily release hydrogen atoms and hydrogen gas are stacked between the silicon substrate 1 and the hydrogen isolation layer 5, and the second passivation layer 6 that does not easily release hydrogen atoms and hydrogen gas is stacked on the side of the hydrogen isolation layer 5 that is away from the silicon substrate 1. The hydrogen released by the silicon nitride layer 3 and the silicon oxynitride layer 4 can be fully utilized to recombine with the dangling bonds; further, it can also avoid the situation where the silicon nitride layer 3 or the silicon oxynitride layer 4 is stacked on the side of the hydrogen isolation layer 5 that is away from the silicon substrate 1, which causes the hydrogen atoms to pass through the pores and return to the surface of the silicon substrate 1.
[0036] In the embodiment of the present application, a hydrogen isolation layer 5 is stacked on the front side of the silicon nitride layer 3 and the silicon oxynitride layer 4 to achieve hydrogen isolation in a physical sense, isolating the hydrogen between the hydrogen isolation layer 5 and the silicon substrate 1. Even under high-temperature sintering, it will not diffuse out, thereby ensuring the hydrogen content inside the battery and the passivation effect of the dangling bonds.
[0037] In addition, the embodiment of the present application uses hydrogen to recombine with dangling bonds, which has a more thorough passivation effect than using hydrogen atoms to recombine with dangling bonds, because hydrogen atoms can also recombine with carriers.
[0038] In one embodiment, the hydrogen isolation layer 5 is deposited by atomic deposition.
[0039] The hydrogen isolation layer 5 is prepared by atomic deposition, which can improve the compactness of the prepared film layer, thereby ensuring that its porosity meets the requirements.
[0040] In one embodiment, the hydrogen isolation layer 5 is one of an aluminum oxide layer, a magnesium oxide layer, a magnesium fluoride layer and a zinc oxide layer.
[0041] The aluminum oxide layer, the magnesium oxide layer, the magnesium fluoride layer and the zinc oxide layer are all film layers that can be prepared by atomic deposition.
[0042] It can be understood that other membrane layers that can be prepared by atomic deposition and whose porosity satisfies the particle diameter smaller than that of hydrogen molecules and larger than that of hydrogen atoms can be used as the hydrogen isolation layer 5 of the embodiment of the present application.
[0043] In one embodiment, the porosity of the hydrogen barrier layer 5 is 0.1-0.2 nm.
[0044] Based on the fact that the particle diameter of hydrogen molecules is about 0.2 nm and the particle diameter of hydrogen atoms is about 0.1 nm, the porosity of the hydrogen isolation layer 5 is set to be smaller than the particle diameter of hydrogen molecules and larger than the particle diameter of hydrogen atoms, so that hydrogen cannot pass through but hydrogen atoms can pass through. In addition, under the condition of such porosity, the passage of carriers will not be affected.
[0045] The porosity of the hydrogen barrier layer 5 may be, for example, 0.1 nm, 0.13 nm, 0.144 nm, 0.15 nm, 0.16 nm, 0.18 nm or 0.2 nm.
[0046] In one embodiment, the refractive indices of the first passivation layer 2 , the silicon nitride layer 3 , the silicon oxynitride layer 4 , the hydrogen isolation layer 5 , and the second passivation layer 6 decrease in sequence.
[0047] The first passivation layer 2, the silicon nitride layer 3, the silicon oxynitride layer 4, the hydrogen isolation layer 5 and the second passivation layer 6 are stacked in sequence on the surface of the silicon substrate 1. The further away the film layer is from the silicon substrate 1, the smaller the refractive index is, which can promote the silicon substrate 1 to absorb light, improve the light absorption rate, and further improve the photoelectric conversion efficiency of the crystalline silicon solar cell.
[0048] The refractive index of the first passivation layer 2, the silicon nitride layer 3, the silicon oxynitride layer 4, the hydrogen isolation layer 5 and the second passivation layer 6 can be adjusted by adjusting the preparation method, the thickness of the prepared film layer, the density of the prepared film layer and other related processes when preparing the corresponding film layer so that the refractive index of the film layer meets the application requirements.
[0049] In one embodiment, the hydrogen isolation layer 5 has a thickness of 5-30 nm and a refractive index of 1.6-1.7.
[0050] Although the porosity of the hydrogen isolation layer 5 can be limited to achieve the effect of retaining hydrogen molecules for passivating dangling bonds and allowing hydrogen atoms to pass through, the ion diameters of hydrogen and hydrogen atoms are very small, and if the thickness of the hydrogen isolation layer 5 is too thin, it is difficult to ensure the passivation efficiency of dangling bonds and prevent some hydrogen molecules from passing through.
[0051] By limiting the thickness of the hydrogen isolation layer 5 to a certain extent, even if some hydrogen molecules pass through the pores, their passing speed is slow due to the certain thickness and no airflow is formed, thereby preventing some hydrogen molecules that might have originally passed through from passing through. When the thickness of the hydrogen isolation layer 5 is relatively thick, the range of porosity can be appropriately relaxed to avoid the situation where a porosity that is too small is difficult to achieve, resulting in an unsatisfactory passivation effect.
[0052] When the thickness of the hydrogen isolation layer 5 is relatively thick, the range of the porosity can be appropriately relaxed, thereby increasing the carrier transmission speed.
[0053] The thickness of the hydrogen isolation layer 5 cannot be too thick. A too thick hydrogen isolation layer 5 increases the material cost and increases the thickness of the crystalline silicon solar cell, thus affecting the light absorption.
[0054] In the embodiment of the present application, the thickness of the hydrogen isolation layer 5 is limited to 5-30 nm, for example, it can be 5 nm, 8 nm, 15 nm, 19 nm, 21 nm, 25 nm, 27 nm, 28 nm or 30 nm.
[0055] The embodiment of the present application limits the thickness of the hydrogen isolation layer 5 to ensure that the crystalline silicon solar cell has a better passivation effect and a higher photoelectric conversion rate, while saving material costs.
[0056] The refractive index of the hydrogen isolation layer 5 is smaller than the refractive index of the silicon oxynitride layer 4 and larger than the refractive index of the second passivation layer 6 .
[0057] In one embodiment, the thickness of the hydrogen barrier layer 5 is greater than or equal to the thickness of the first passivation layer 2 .
[0058] The thickness of the hydrogen isolation layer 5 is greater than or equal to the thickness of the first passivation layer 2 , so that the hydrogen isolation layer 5 can achieve a passivation effect on dangling bonds, promoting the recombination of hydrogen with dangling bonds on the surface of the silicon substrate 1 .
[0059] In one embodiment, the first passivation layer 2 includes an aluminum oxide layer. After annealing, the aluminum oxide layer can provide a good field passivation effect and improve the photoelectric conversion efficiency of the crystalline silicon solar cell.
[0060] In one embodiment, the silicon nitride layer 3 includes at least one silicon nitride film layer, and the at least one silicon nitride film layer is stacked in sequence between the first passivation layer 2 and the silicon nitride oxide layer 4; the thickness of the silicon nitride film layer is 10-20nm, and the refractive index of the at least one silicon nitride film layer decreases layer by layer in a direction away from the silicon substrate 1, and the refractive index of the silicon nitride film layer is 1.9 to 2.3.
[0061] The crystalline silicon solar cell provided in the embodiment of the present application can be a structure of a multi-layer silicon nitride film layer. The multi-layer silicon nitride film layer satisfies that the refractive index decreases layer by layer along the direction away from the silicon substrate 1, which can improve the light absorption efficiency. The refractive index of the silicon nitride film layer is 1.9 to 2.3. For example, the silicon nitride film layer is 3 layers, and the refractive index of the 3 layers of silicon nitride film layers along the direction away from the silicon substrate 1 is 2.3, 2.1 and 1.9 respectively. The thickness of a silicon nitride film layer is 10-20nm, for example, it can be 10nm, 12nm, 14nm, 17m, 18nm or 20nm.
[0062] In one embodiment, the silicon oxynitride layer 4 includes at least one silicon oxynitride film layer, and the at least one silicon oxynitride film layer is stacked in sequence between the silicon nitride layer 3 and the hydrogen isolation layer 5; the thickness of the silicon oxynitride film layer is 10-20nm, and the refractive index of the at least one silicon oxynitride film layer decreases layer by layer in a direction away from the silicon substrate 1, and the refractive index of the silicon oxynitride film layer is 1.7 to 1.9.
[0063] The crystalline silicon solar cell provided in the embodiment of the present application may be a structure of a multi-layer silicon oxynitride film layer, and the multi-layer silicon oxynitride film layer satisfies that the refractive index decreases layer by layer along the direction away from the silicon substrate 1, which can improve the light absorption efficiency. The refractive index of the silicon oxynitride film layer is 1.7 to 1.9. For example, the silicon oxynitride film layer is 3 layers, and the refractive index of the three silicon oxynitride film layers along the direction away from the silicon substrate 1 is 1.9, 1.8 and 1.7 respectively. The thickness of a layer of silicon oxynitride film layer is 10-20nm, for example, it can be 10nm, 12nm, 14nm, 17m, 18nm or 20nm.
[0064] In one embodiment, the second passivation layer 6 includes at least one silicon oxide layer, which is stacked in sequence on the front side of the hydrogen isolation layer 5, the thickness of the silicon oxide layer on one side is 10-20nm, and the refractive index of the at least one silicon oxide layer decreases layer by layer in a direction away from the silicon substrate 1, and the refractive index of the silicon oxide layer is 1.5 to 1.6.
[0065] The crystalline silicon solar cell provided in the embodiment of the present application may be a structure of a multi-layer silicon oxide layer, and the multi-layer silicon oxide layer satisfies that the refractive index decreases layer by layer along the direction away from the silicon substrate 1, which can improve the light absorption efficiency. The refractive index of the silicon oxide layer is 1.5 to 1.6. For example, the silicon oxide layer is 3 layers, and the refractive index of the 3 silicon oxide layers along the direction away from the silicon substrate 1 is 1.6, 1.56 and 1.5 respectively. The thickness of a silicon oxide layer is 10-20nm, for example, it can be 10nm, 12nm, 14nm, 17m, 18nm or 20nm.
[0066] In one embodiment, the total thickness of the first passivation layer 2, the silicon nitride layer 3, the silicon oxynitride layer 4, the hydrogen isolation layer 5 and the second passivation layer 6 is 50-150 nm.
[0067] The thickness of the crystalline silicon solar cell is limited by limiting the total thickness of the first passivation layer 2, the silicon nitride layer 3, the silicon oxynitride layer 4, the hydrogen isolation layer 5 and the second passivation layer 6, and the absorption of sunlight by the silicon substrate 1 is ensured. The total thickness can be, for example, 50 nm, 60 nm, 70 nm, 89 nm, 98 nm, 126 nm, 135 nm or 150 nm.
[0068] The following will conduct performance tests on the structure of the crystalline silicon solar cell provided in the embodiment of the present application and the structure of the crystalline silicon solar cell provided in the comparative example.
[0069] [Example 1]
[0070] The specific structure of a crystalline silicon solar cell includes: a silicon substrate, on the front of which an aluminum oxide layer, two silicon nitride layers, two silicon oxynitride layers, a magnesium oxide layer and two silicon oxide layers are stacked in sequence. The magnesium oxide layer is made by atomic deposition, with a thickness of 15nm and a porosity of 0.16nm.
[0071] [Comparative Example 1]
[0072] The specific structure of a crystalline silicon solar cell includes: a silicon substrate, on the front side of which an aluminum oxide layer, two silicon nitride layers, two silicon oxynitride layers and two silicon oxide layers are sequentially stacked.
[0073] In Example 1 and Comparative Example 1, the silicon substrate is a double-sided polished N-type single crystal silicon with a thickness of 200 μm. The thickness, refractive index, and preparation method of the aluminum oxide layer, the two silicon nitride layers, the two silicon oxynitride layers, and the two silicon oxide layers are the same. The crystalline silicon solar cells of Example 1 and Comparative Example 1 also include the same back film layer structure, and a complete crystalline silicon solar cell has been obtained that can output current. The only difference between the crystalline silicon solar cell of Comparative Example 1 and Example 1 is that Comparative Example 1 does not include a magnesium oxide layer.
[0074] The crystalline silicon solar cells prepared in Example 1 and Comparative Example 1 were subjected to performance tests to obtain the open circuit voltage Voc, short circuit current density Jsc, fill factor FF, and photoelectric conversion efficiency PCE of the corresponding cell devices. The test results are shown in Table 1.
[0075] Table 1. Performance test results of crystalline silicon solar cells of Example 1 and Comparative Example 1
[0076]
[0077] The data in Table 1 show that the short-circuit current density, open-circuit voltage, fill factor and photoelectric conversion efficiency of the crystalline silicon solar cell prepared in the manner of Example 1 are significantly improved.
[0078] The embodiment of the present application may also provide a photovoltaic assembly (not shown), the photovoltaic assembly comprising a plurality of solar cells connected in series and / or in parallel; wherein at least one solar cell is a crystalline silicon solar cell as described above. The plurality of crystalline silicon solar cells in series form a cell string, and adjacent crystalline silicon solar cells may be connected together by string welding.
[0079] The embodiment of the present application can provide a photovoltaic system, including the photovoltaic components in any of the above embodiments. 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 may form multiple photovoltaic arrays. The photovoltaic array is connected to a 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.
[0080] It should be noted that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. 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.
[0081] 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.
[0082] 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.
[0083] 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 crystalline silicon solar cell, characterized in that: include: Silicon substrate; A first passivation layer, a silicon nitride layer and a silicon oxynitride layer, wherein the first passivation layer, the silicon nitride layer and the silicon oxynitride layer are sequentially stacked on the front surface of the silicon substrate; A hydrogen isolation layer, the hydrogen isolation layer is stacked on the front side of the silicon oxynitride layer; the porosity of the hydrogen isolation layer is smaller than the particle diameter of hydrogen molecules and larger than the particle diameter of hydrogen atoms; A second passivation layer is stacked on a side of the hydrogen isolation layer away from the silicon substrate.
2. The crystalline silicon solar cell according to claim 1, characterized in that: The hydrogen isolation layer is deposited by atomic deposition.
3. The crystalline silicon solar cell according to claim 2, characterized in that: The hydrogen isolation layer is one of an aluminum oxide layer, a magnesium oxide layer, a magnesium fluoride layer and a zinc oxide layer.
4. The crystalline silicon solar cell according to any one of claims 1 to 3, characterized in that: The porosity of the hydrogen isolation layer is 0.1-0.2 nm.
5. The crystalline silicon solar cell according to claim 1, characterized in that: The refractive indices of the first passivation layer, the silicon nitride layer, the silicon oxynitride layer, the hydrogen isolation layer, and the second passivation layer decrease in sequence.
6. The crystalline silicon solar cell according to claim 5, characterized in that: The thickness of the hydrogen isolation layer is 5-30 nm, and the refractive index is 1.6-1.
7.
7. The crystalline silicon solar cell according to claim 1, characterized in that: The thickness of the hydrogen isolation layer is greater than or equal to the thickness of the first passivation layer.
8. The crystalline silicon solar cell according to claim 1, characterized in that: The first passivation layer includes an aluminum oxide layer.
9. The crystalline silicon solar cell according to claim 1, characterized in that: The silicon nitride layer includes at least one silicon nitride film layer, and the at least one silicon nitride film layer is stacked in sequence between the first passivation layer and the silicon nitride oxide layer; the thickness of one silicon nitride film layer is 10-20nm, and the refractive index of at least one silicon nitride film layer decreases layer by layer in a direction away from the silicon substrate, and the refractive index of the silicon nitride film layer is 1.9 to 2.
3.
10. The crystalline silicon solar cell according to claim 1, characterized in that: The silicon oxynitride layer includes at least one silicon oxynitride film layer, and the at least one silicon oxynitride film layer is stacked in sequence between the silicon nitride layer and the hydrogen isolation layer; the thickness of one silicon oxynitride film layer is 10-20nm, and the refractive index of at least one silicon oxynitride film layer decreases layer by layer in a direction away from the silicon substrate, and the refractive index of the silicon oxynitride film layer is 1.7-1.
9.
11. The crystalline silicon solar cell according to claim 1, characterized in that: The second passivation layer includes at least one silicon oxide layer, which is stacked in sequence on the front side of the hydrogen isolation layer. The thickness of the silicon oxide layer on one side is 10-20nm, and the refractive index of at least one silicon oxide layer decreases layer by layer in a direction away from the silicon substrate. The refractive index of the silicon oxide layer is 1.5 to 1.
6.
12. The crystalline silicon solar cell according to claim 1, characterized in that: The total thickness of the first passivation layer, the silicon nitride layer, the silicon oxynitride layer, the hydrogen isolation layer and the second passivation layer is 50-150 nm.
13. A photovoltaic module, characterized in that: The photovoltaic module comprises a plurality of solar cells connected in series and / or in parallel; wherein at least one solar cell is the crystalline silicon solar cell according to any one of claims 1 to 12.