Solar cell and its preparation method, tandem solar cell and its preparation method

Abstract

This application relates to the technical field of solar cells, and specifically relates to a solar cell and its preparation method, a tandem solar cell and its preparation method. The solar cell includes an electrode layer and a functional layer stacked on one side of a substrate; a first film layer is provided between the electrode layer and the functional layer. The functions of the first film layer include increasing the optical path, being able to change the interface to reduce reflection loss, and further increasing the optical path of incident light by improving the scattering ability of incident light, effectively improving the light absorption ability of the solar cell and solving the problem of how to improve the light conversion efficiency of the solar cell.

Description

Technical Field

[0001] The present application relates to the technical field of solar cells, and in particular, to a solar cell and a method for preparing the same, a tandem solar cell and a method for preparing the same. Background Art

[0002] With the rapid development of technology and economy, as a renewable green energy source, how to better develop and utilize solar energy has become one of the most important topics in energy research.

[0003] A solar cell is a device that directly converts light energy into electrical energy through the photovoltaic effect. However, the light conversion efficiency of solar cells is not high. With the development of solar cell technology and the desire for new energy, higher requirements are put forward for the light conversion efficiency of solar cells. Summary of the Invention

[0004] In view of this, embodiments of the present application provide a solar cell and a method for preparing the same, a tandem solar cell and a method for preparing the same, so as to solve the problem of how to improve the light conversion efficiency of solar cells.

[0005] In a first aspect, an embodiment of the present application provides a solar cell, which includes: a substrate; an electrode layer and a functional layer stacked on one side of the substrate; a first film layer is provided between the electrode layer and the functional layer, and the function of the first film layer includes increasing the optical path.

[0006] In combination with the first aspect, in an embodiment of the present application, the electrode layer includes a first electrode layer and a second electrode layer, and the functional layer is located between the first electrode layer and the second electrode layer; the first film layer is located between the first electrode layer and the functional layer, and / or, the first film layer is located between the second electrode layer and the functional layer; preferably, the first film layer includes scattering particles; preferably, the scattering particles include at least one of zirconia, silica, alumina, titanium dioxide, and zinc oxide; preferably, the transparency of the scattering particles is greater than 80%.

[0007] In combination with the first aspect, in an embodiment of the present application, the function of the first film layer includes self-healing, and the first film layer further includes a polymer material for dispersing scattering particles; preferably, the polymer material includes at least one of transparent polymer materials that self-heal using hydrogen bonds, self-heal using nitroxide radicals, and self-heal using the Diels-Alder reaction.

[0008] In combination with the first aspect, in an embodiment of the present application, the solar cell further includes a second film layer. The first film layer is located between the first electrode layer and the functional layer. The second film layer is located between the first film layer and the first electrode layer, and / or the second film layer is located between the functional layer and the second electrode layer; preferably, the solar cell further includes a second film layer. The first film layer is located between the second electrode layer and the functional layer. The second film layer is located between the first film layer and the second electrode layer, and / or the second film layer is located between the functional layer and the first electrode layer; preferably, the solar cell further includes a second film layer. The first film layer is located between the first electrode layer and the functional layer and between the second electrode layer and the functional layer. The second film layer is located between the first film layer and the first electrode layer, and / or the second film layer is located between the first film layer and the second electrode layer; preferably, the function of the second film layer includes improving the output power of the solar cell.

[0009] In combination with the first aspect, in an embodiment of the present application, the solar cell is a silicon-based solar cell. The functional layer includes an n-type silicon layer, a first i-type silicon layer, a c-type silicon layer, a second i-type silicon layer, and a p-type silicon layer arranged in layers. The first film layer is located between the first electrode layer and the n-type silicon layer, and / or the first film layer is located between the second electrode layer and the p-type silicon layer.

[0010] In combination with the first aspect, in an embodiment of the present application, the solar cell is a perovskite solar cell. The functional layer includes a first transport layer, a photo-electric conversion layer, and a second transport layer arranged in layers. The first film layer is located between the first electrode layer and the first transport layer, and / or the first film layer is located between the second electrode layer and the second transport layer.

[0011] In combination with the first aspect, in an embodiment of the present application, the solar cell further includes a first encapsulation layer. The second electrode layer is located on the side of the first electrode layer away from the substrate. The first encapsulation layer is provided on the surface of the second electrode layer away from the substrate, and covers the two side surfaces of the solar cell and is connected to the substrate; preferably, the material of the first encapsulation layer includes any one or a combination of alumina and silica.

[0012] In the second aspect, an embodiment of the present application provides a tandem solar cell. The tandem solar cell includes a first cell and a second cell arranged in layers. At least one of the first cell and the second cell is the solar cell mentioned in the first aspect; preferably, the first cell includes a perovskite solar cell, and the second cell includes a silicon-based solar cell; preferably, the perovskite solar cell is arranged in layers on the side of the silicon-based solar cell away from the substrate; preferably, both the first cell and the second cell include perovskite solar cells; preferably, the tandem solar cell includes a second encapsulation layer. The second encapsulation layer covers the perovskite solar cell and the silicon-based solar cell, and is connected to the substrate; preferably, the material of the second encapsulation layer includes any one or a combination of alumina and silica.

[0013] In a third aspect, an embodiment of the present application provides a method for manufacturing a solar cell, the method comprising providing a substrate; preparing a first electrode layer on one side of the substrate; coating a transparent polymer material containing scattering particles on the surface of the first electrode layer to obtain a first film layer; preparing a functional layer on the surface of the first film layer; and preparing a second electrode layer on the functional layer to obtain a solar cell.

[0014] In a fourth aspect, an embodiment of the present application provides a method for manufacturing a tandem solar cell, the method comprising manufacturing a first solar cell and a second solar cell according to the method for manufacturing a solar cell mentioned in the third aspect; stacking the manufactured second solar cell on one side of the manufactured first solar cell, and electrically connecting the first solar cell and the second solar cell.

[0015] An embodiment of the present application provides a solar cell and a method for manufacturing the same, and a tandem solar cell and a method for manufacturing the same. The solar cell is provided with a first film layer between an electrode layer and a functional layer stacked on one side of a substrate. The functions of the first film layer include increasing the optical path, being able to change the interface to reduce reflection loss, and further increasing the optical path of incident light by improving the scattering ability of incident light, effectively improving the light absorption ability of the solar cell, and solving the problem of how to improve the light conversion efficiency of the solar cell. Description of the Drawings

[0016] Figure 1 It is a schematic structural diagram of a solar cell provided in an embodiment of the present application.

[0017] Figure 2a It is a schematic structural diagram of a solar cell provided in another embodiment of the present application.

[0018] Figure 2b It is a schematic structural diagram of a solar cell provided in another embodiment of the present application.

[0019] Figure 3a It is a schematic structural diagram of a solar cell provided in yet another embodiment of the present application.

[0020] Figure 3b It is a schematic structural diagram of a solar cell provided in yet another embodiment of the present application.

[0021] Figure 3c It is a schematic structural diagram of a solar cell provided in yet another embodiment of the present application.

[0022] Figure 3d It is a schematic structural diagram of a solar cell provided in yet another embodiment of the present application.

[0023] Figure 3e It is a schematic structural diagram of a solar cell provided in yet another embodiment of the present application.

[0024] Figure 3f Schematic diagram of the structure of a solar cell provided in another embodiment of the present application.

[0025] Figure 3g Schematic diagram of the structure of a solar cell provided in another embodiment of the present application.

[0026] Figure 3h Schematic diagram of the structure of a solar cell provided in another embodiment of the present application.

[0027] Figure 3i Schematic diagram of the structure of a solar cell provided in another embodiment of the present application.

[0028] Figure 4 Schematic diagram of the structure of a silicon-based solar cell provided in an embodiment of the present application.

[0029] Figure 5 Schematic diagram of the structure of a silicon-based solar cell provided in another embodiment of the present application.

[0030] Figure 6 Schematic diagram of the structure of a perovskite cell provided in an embodiment of the present application.

[0031] Figure 7 Schematic diagram of the structure of a perovskite cell provided in another embodiment of the present application.

[0032] Figure 8 Schematic diagram of the structure of a solar cell provided in an embodiment of the present application, where the first film layer is in a damaged state.

[0033] Figure 9 Schematic diagram of the structure of a solar cell provided in an embodiment of the present application, where the damage repair of the first film layer is completed.

[0034] Figure 10 Schematic diagram of the structure of a solar cell provided in another embodiment of the present application.

[0035] Figure 11 Schematic diagram of the structure of a tandem solar cell provided in an embodiment of the present application.

[0036] Figure 12a Schematic diagram of the structure of a tandem solar cell provided in another embodiment of the present application.

[0037] Figure 12b Schematic diagram of the structure of a tandem solar cell provided in another embodiment of the present application.

[0038] Figure 12c Schematic diagram of the structure of a tandem solar cell provided in another embodiment of the present application.

[0039] Figure 12d This is a schematic structural diagram of a tandem solar cell provided in another embodiment of the present application.

[0040] Figure 13 The figure shows a schematic flow chart of a method for manufacturing a solar cell provided in an embodiment of the present application.

[0041] Figure 14 The figure shows a schematic flow chart of a method for manufacturing a tandem solar cell provided in an embodiment of the present application. Detailed implementation manners

[0042] Next, the technical solutions in the embodiments of the present application will be clearly and completely described with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0043] As a renewable clean energy source, solar energy is not only rich in resources, but also can be developed and utilized for free, and does not cause pollution to the environment, and does not require mining and transportation, having great application potential and development prospects.

[0044] Since the technology and process of silicon-based solar cells are relatively mature, the conversion efficiency of the cells is relatively high and the performance is stable, which has always occupied a dominant position in the market. The highest conversion efficiency of the existing developed silicon-based solar cells is very close to the theoretical limit value, and the conversion efficiency of the mainstream silicon-based solar cells has faced a bottleneck.

[0045] Therefore, how to further improve the light conversion efficiency of solar cells is an urgent problem to be solved.

[0046] In view of this, the present application provides a solar cell and its manufacturing method, a tandem solar cell and its manufacturing method to solve the problem of the light conversion efficiency of solar cells.

[0047] Figure 1 This is a schematic structural diagram of a solar cell provided in an embodiment of the present application. As Figure 1 shown, the solar cell 1 includes a substrate 100, and an electrode layer 120 and a functional layer 14 are stacked on one side of the substrate 100; a first film layer 11 is disposed between the electrode layer 120 and the functional layer 14, and the function of the first film layer 11 includes increasing the optical path.

[0048] Specifically, the solar cell 1 is composed of a plurality of solar cell units electrically connected in sequence. A solar cell unit refers to the smallest unit having the function of a solar cell that can extract electric power.

[0049] Exemplarily, the solar cell 1 can be a rigid cell structure with a glass or other rigid material as the substrate, or a flexible cell structure with a polymer flexible material such as polyimide (PI), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), etc. as the substrate. When the solar cell is a flexible structure, the solar cell can not only be stretched, but also bent and folded, further reducing the floor area of the solar cell and facilitating portability.

[0050] Exemplarily, the solar cell 1 includes one or more of solar cells with different structures such as silicon-based solar cells, arsenic telluride, copper indium gallium selenide and other semiconductor solar cells, perovskite solar cells, and organic solar cells.

[0051] Specifically, the orthographic projection of the first film layer 11 on the substrate 100 covers the orthographic projection of the electrode layer 120 on the substrate 100, and the orthographic projection of the first film layer 11 on the substrate 100 covers the orthographic projection of the functional layer 14 on the substrate 100. The first film layer 11 can be a self-healing functional film layer, and the material of the first film layer 11 can be an organic material.

[0052] Exemplarily, the number of the first film layers 11 can be one layer or multiple layers. The multiple first film layers 11 can be stacked or spaced. The present application does not limit the specific structural setting of the first film layer 11, as long as the first film layer 11 can increase the optical path.

[0053] In the solar cell provided by the embodiment of the present application, the electrode layer 120 and the functional layer 14 are stacked on one side of the substrate 100; the first film layer 11 is disposed between the electrode layer 120 and the functional layer 14. The functions of the first film layer 11 include increasing the optical path, being able to change the interface to reduce reflection loss, and further increasing the optical path of the incident light by improving the scattering ability of the incident light, effectively improving the light absorption ability of the solar cell 1 and solving the problem of how to improve the light conversion efficiency of the solar cell 1.

[0054] Figure 2a It is a schematic structural diagram of the solar cell provided in another embodiment of the present application. As Figure 2a shown, the electrode layer 120 includes a first electrode layer 10 and a second electrode layer 12, the functional layer 14 is located between the first electrode layer 10 and the second electrode layer 12; the first film layer 11 is located between the first electrode layer 10 and the functional layer 14.

[0055] Specifically, the first electrode layer 10 is disposed on the substrate 100, and the second electrode layer 12 is disposed on the side of the first electrode layer 10 away from the substrate 100. The first electrode layer 10 and the second electrode layer 12 are oppositely disposed. The first electrode layer 10 can be a top electrode layer, and the second electrode layer 12 can be a bottom electrode layer.

[0056] Exemplarily, the first film layer 11 includes scattering particles 110, which are used to scatter the light incident on the first film layer 11 after passing through the first electrode layer 10 and / or the second electrode layer 12. The scattering particles 110 can increase the light flux. Among them, the number of the scattering particles 110 is multiple, and the multiple scattering particles 110 can be uniformly and continuously distributed in the first film layer 11. The particle sizes of the multiple scattering particles 110 can be the same, or the particle sizes of some of the scattering particles 110 can be different. The concentration of the scattering particles 110 can be set according to the actual situation. The present application does not make specific limitations on the scattering particles 110, as long as they can scatter the incident light.

[0057] Exemplarily, the material of the scattering particles 110 includes at least one of zirconia, silica, alumina, titanium dioxide, and zinc oxide, or can also be other particles with characteristics such as high refractive index, low scattering, high transmittance, and high temperature stability. The color of the scattering particles 110 includes white or colorless. The color of the scattering particles 110 can also be other colors, as long as they can scatter light. The transparency of the scattering particles is greater than 80%.

[0058] Figure 2b This is a schematic structural diagram of a solar cell provided in another embodiment of the present application. As Figure 2b shown, the first film layer 11 is located between the second electrode layer 12 and the functional layer 14. The first film layer 11 needs to have three elements: high transparency, with scattering particles 110, and having a self-healing function.

[0059] Specifically, in combination with Figure 2a and Figure 2b shown, the orthographic projection of the first film layer 11 on the substrate 100 covers the orthographic projection of the functional layer 14 on the substrate 100. The first film layer 11 can be located between the first electrode layer 10 and the functional layer 14, or can also be located between the second electrode layer 12 and the functional layer 14. Of course, the first film layer 11 can be provided between the first electrode layer and the functional layer 14, and between the second electrode layer and the functional layer 14. The present application does not limit the specific position and number of layers of the first film layer 11.

[0060] Among them, the function of the first film layer 11 includes self-healing, and the first film layer 11 further includes a polymer material for dispersing the scattering particles 110.

[0061] Optionally, the polymer material includes at least one of transparent polymer materials that self-heal using hydrogen bonds, self-heal using nitroxide radicals, and self-heal using Diels-Alder reactions.

[0062] The solar cell provided by an embodiment of the present application has a first film layer 11 located between a first electrode layer 10 and a functional layer 14, and / or the first film layer 11 is located between a second electrode layer 12 and the functional layer 14. When ambient light is incident on the first film layer 11, a plurality of scattering particles 110 in the first film layer 11 can scatter the incident light, increase the light flux, and achieve the effects of improving the incident light, reducing the reflectivity, and increasing the battery stability.

[0063] Figure 3a It is a schematic structural diagram of a solar cell provided in another embodiment of the present application. As Figure 3a shown, the solar cell further includes a second film layer 15. The first film layer 11 is located between the first electrode layer 10 and the functional layer 14. The second film layer 15 is located between the first film layer 11 and the first electrode layer 10.

[0064] Figure 3b It is a schematic structural diagram of a solar cell provided in another embodiment of the present application. As Figure 3b shown, the solar cell further includes a second film layer 15. The first film layer 11 is located between the first electrode layer 10 and the functional layer 14, and the second film layer 15 is located between the second electrode layer 12 and the functional layer 14.

[0065] Figure 3c It is a schematic structural diagram of a solar cell provided in another embodiment of the present application. As Figure 3c shown, the solar cell further includes a second film layer 15. The first film layer 11 is located between the first electrode layer 10 and the functional layer 14. The second film layer 15 is located between the first film layer 11 and the first electrode layer 10, and the second film layer 15 is located between the second electrode layer 12 and the functional layer 14.

[0066] Figure 3d It is a schematic structural diagram of a solar cell provided in another embodiment of the present application. As Figure 3d shown, the first film layer 11 is located between the second electrode layer 12 and the functional layer 14, and the second film layer 15 is located between the first film layer 11 and the second electrode layer 12.

[0067] Figure 3e It is a schematic structural diagram of a solar cell provided in another embodiment of the present application. As Figure 3e shown, the first film layer 11 is located between the second electrode layer 12 and the functional layer 14, and the second film layer 15 is located between the functional layer 14 and the first electrode layer 10.

[0068] Figure 3f It is a schematic structural diagram of a solar cell provided in another embodiment of the present application. As Figure 3fAs shown, the first film layer 11 is located between the second electrode layer 12 and the functional layer 14, the second film layer 15 is located between the first film layer 11 and the second electrode layer 12, and the second film layer 15 is located between the functional layer 14 and the first electrode layer 10.

[0069] Figure 3g This is a schematic structural diagram of a solar cell provided in another embodiment of the present application. As Figure 3g shown, the first film layer 11 is located between the first electrode layer 10 and the functional layer 14 and the first film layer 11 is located between the second electrode layer 12 and the functional layer 14, and the second film layer 15 is located between the first film layer 11 and the first electrode layer 10.

[0070] Figure 3h This is a schematic structural diagram of a solar cell provided in another embodiment of the present application. As Figure 3h shown, the first film layer 11 is located between the first electrode layer 10 and the functional layer 14 and between the second electrode layer 12 and the functional layer 14, and the second film layer 15 is located between the first film layer 11 and the second electrode layer 12.

[0071] Figure 3i This is a schematic structural diagram of a solar cell provided in another embodiment of the present application. As Figure 3i shown, the first film layer 11 is located between the first electrode layer 10 and the functional layer 14 and between the second electrode layer 12 and the functional layer 14, the second film layer 15 is located between the first film layer 11 and the first electrode layer 10, and the second film layer 15 is located between the first film layer 11 and the second electrode layer 12.

[0072] Exemplarily, the function of the second film layer 15 includes improving the output power of the solar cell 1.

[0073] The solar cell provided in the embodiment of the present application can achieve the effects of improving incident light, reducing reflectivity, and increasing battery stability by providing the first film layer 11 and the second film layer 15.

[0074] In some embodiments, the solar cell 1 is a silicon-based solar cell, the functional layer 14 includes an n-type silicon layer, a first i-type silicon layer, a c-type silicon layer, a second i-type silicon layer, and a p-type silicon layer arranged in layers, the first film layer 11 is located between the first electrode layer 10 and the n-type silicon layer, and / or the first film layer 11 is located between the second electrode layer 12 and the p-type silicon layer.

[0075] The following combines Figure 4 and Figure 5 to specifically introduce the first film layer in the silicon-based solar cell.

[0076] Figure 4 This is a schematic structural diagram of a silicon-based solar cell provided in an embodiment of the present application. As Figure 4As shown, the solar cell 1 is a silicon-based solar cell. The solar cell 1 includes an n-type silicon layer 130 disposed on one side of the first electrode layer 10, and a first film layer 11 is located between the first electrode layer 10 and the n-type silicon layer 130.

[0077] Exemplarily, the first electrode layer 10 of the silicon-based solar cell includes a metal electrode, which is the current output terminal of the silicon-based solar cell. It draws the current out of the silicon-based solar cell for use by an external circuit.

[0078] Among them, the first film layer 11 located between the first electrode layer 10 and the n-type silicon layer 130 includes a plurality of scattering particles 110. The scattering particles 110 can scatter the light incident on the first film layer 11 after penetrating the first electrode layer 10 to increase the light flux.

[0079] Exemplarily, the silicon-based solar cell includes at least one of a heterojunction cell and a passivated contact cell.

[0080] Figure 5 This is a schematic structural diagram of the silicon-based solar cell provided in another embodiment of the present application. As Figure 5 shown, the silicon-based solar cell further includes a p-type silicon layer 131. The p-type silicon layer 131 is located on the side of the n-type silicon layer 130 close to the second electrode layer 12, and a first film layer 112 is located between the second electrode layer 12 and the p-type silicon layer 131.

[0081] Specifically, the silicon-based solar cell includes a first electrode layer 10, a second film layer 15, a first film layer 11, an n-type silicon layer 130 / n-type polycrystalline silicon (poly-Si), a first i-type silicon layer / tunneling oxide layer 132, a c-type silicon layer 133, a second i-type silicon layer / p+ emitter 134, a p-type silicon layer 131 / aluminum oxide (Al2O3) passivation layer, a first film layer 11, a second film layer 15, and a second electrode layer 12. Among them, the first electrode layer 10 on one side of the n-type silicon layer 130 is an oxide transparent bottom electrode layer, which is the negative electrode of the silicon-based solar cell; the second electrode layer 12 on one side of the p-type silicon layer 131 is an oxide transparent top electrode layer, which is the positive electrode of the silicon-based solar cell. The second film layer 15 can be a silicon nitride (SiNx) antireflection layer. The silicon nitride (SiNx) antireflection layer can reduce the reflected light / increase the light transmittance, improve the utilization rate of light by the solar cell 1, and thus improve the output power of the solar cell 1. Specifically, the antireflection layer can include any one or a combination of silicon nitride, silicon oxide, and silicon oxynitride.

[0082] Among them, the first film layer 11 located between the first electrode layer 10 and the n-type silicon layer 130 includes a plurality of scattering particles 110, and the first film layer 11 located between the second electrode layer 12 and the p-type silicon layer 131 includes a plurality of scattering particles 110. The scattering particles 110 can scatter the light incident into the silicon-based solar cell after passing through the first electrode layer 10 and the second electrode layer 12, so as to increase the light flux.

[0083] In the solar cell provided by the embodiment of the present application, the first film layer 11 is disposed between the first electrode layer 10 and the n-type silicon layer 130 of the silicon-based solar cell, and / or the first film layer 11 is disposed between the second electrode layer 12 and the p-type silicon layer 131 of the silicon-based solar cell. When ambient light penetrates the first electrode layer 10 and the second electrode layer 12 and then enters the silicon-based solar cell, the plurality of scattering particles 110 in the first film layer 11 can scatter the incident light, increase the light flux, and thus improve the light conversion efficiency of the silicon-based solar cell.

[0084] In some embodiments, the solar cell is a perovskite solar cell, and the functional layer includes a first transport layer, a photoelectric conversion layer, and a second transport layer which are stacked. The first film layer is located between the first electrode layer and the first transport layer, and / or the first film layer is located between the second electrode layer and the second transport layer.

[0085] The following will be combined with Figure 6 and Figure 7 to specifically introduce the first film layer in the perovskite cell.

[0086] Figure 6 is a schematic structural diagram of a perovskite cell provided in an embodiment of the present application. As Figure 6 shown, the perovskite cell includes a first transport layer 115 disposed on one side of the first electrode layer 10, and the first film layer 11 is located between the first electrode layer 10 and the first transport layer 115.

[0087] Exemplarily, the first electrode layer 10 may be a bottom electrode layer. Specifically, the first electrode layer 10 may be a TCO (transparent oxide) transparent conductive bottom electrode. The material of the first electrode layer 10 may be any one of indium tin oxide (ITO), fluorine-doped SnO2 conductive glass (FTO), and aluminum-doped zinc oxide transparent conductive glass (AZO).

[0088] Exemplarily, the first transport layer 115 is an electron transport layer. Specifically, the electron transport layer may use an n-type semiconductor material, such as metal oxides such as titanium oxide (TiO2), tin oxide (SnO2), zinc oxide (ZnO), or organic substances such as fullerene (PCBM).

[0089] Among them, the first film layer 11 located between the first electrode layer 10 and the first transport layer 115 includes a plurality of scattering particles 110, and the scattering particles 110 can scatter the light incident on the first film layer 11 to increase the light flux.

[0090] For the solar cell provided by the embodiment of the present application, the first film layer 11 is disposed between the first electrode layer 10 and the first transport layer 115 of the perovskite cell. When ambient light penetrates the first electrode layer 10 and is incident on the first film layer 11, the plurality of scattering particles 110 in the first film layer 11 can scatter the incident light, which can improve the effective light flux of the solar cell 1 and solve the problem of how to improve the light conversion efficiency of the solar cell 1.

[0091] Figure 7 It is a schematic structural diagram of a perovskite cell provided in another embodiment of the present application. As Figure 7 shown, the perovskite cell further includes a second transport layer 117. The second transport layer 117 is disposed on the side of the first transport layer 115 close to the second electrode layer 12, and the first film layer 11 is located between the second electrode layer 12 and the second transport layer 117.

[0092] Specifically, the perovskite cell includes a first electrode layer 10, a first film layer 11, a first transport layer 115, a photo - electric conversion layer 116, a second transport layer 117, a first film layer 11, and a second electrode layer 12 which are stacked in sequence. The first film layer 11 includes a plurality of scattering particles 110. The scattering particles 110 are used to scatter the incident light. When external ambient light penetrates the first electrode layer 10 and is incident on the first film layer 11, the scattering particles 110 in the first film layer 11 can scatter the light incident on the first film layer 11, and the scattered light can be more evenly incident on the first transport layer 115. Similarly, when external ambient light passes through the second electrode layer 12 and is incident on the first film layer 11, the scattering particles 110 in the first film layer 11 can scatter the light incident on the first film layer 11, and the scattered light can be more evenly incident on the second transport layer 117, thereby improving the light flux of the perovskite cell.

[0093] Exemplarily, both the first electrode layer 10 and the second electrode layer 12 of the perovskite cell are transparent electrode layers, both having high light transmittance and low resistance.

[0094] Exemplarily, when the first transport layer 115 is an electron transport layer, the second transport layer 117 is a hole transport layer. The first electrode layer 10 on the side of the electron transport layer is a bottom electrode layer, which is the cathode of the perovskite cell. The second electrode layer 12 on the side of the hole transport layer is a top electrode layer, which is the anode of the perovskite cell.

[0095] Exemplarily, the material of the second electrode layer 12 includes conductive metals such as Au and Ag, and can also be a transparent conductive oxide (TCO) electrode such as indium tin oxide (ITO), or a doped fluorine SnO2 conductive glass (SnO2:F) (abbreviated as FTO), or a carbon electrode.

[0096] Exemplarily, the electron transport layer can use an n-type semiconductor material, such as metal oxides like titanium oxide (TiO2), tin oxide (SnO2), zinc oxide (ZnO), or an organic material such as fullerene (PCBM).

[0097] Exemplarily, the hole transport layer can use a p-type semiconductor material, such as organic materials like 2,2',7,7'-tetrakis[N,N-bis(4-methoxyphenyl)amino]-9,9'-spirobifluorene (spiro-OMeTAD), 3-hexylthiophene (P3HT), poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS), or an inorganic material such as nickel oxide (NiOx).

[0098] Exemplarily, the photoactive conversion layer 116 is a perovskite layer, and the thickness of the photoactive conversion layer 116 is 200 nm to 500 nm. The general formula of the perovskite can be ABX3. Wherein A includes at least one of methylamine (MA+), formamidine (FA+), cesium, and rubidium, B includes at least one of lead (Pb2+), tin (Sn2+), germanium (Ge2+), and copper (Cu2+), and X includes at least one of iodine (I-), bromine (Br-), chlorine (Cl-), and thiocyanate (SCN-).

[0099] Among them, the hole transport layer, the photoactive conversion layer, and the electron transport layer form a stacked structure. Other functional film layers may exist between the photoactive conversion layer and the electron transport layer. The specific structure of the stacked structure in this application is not limited and can be set according to actual situations.

[0100] In the solar cell provided by the embodiment of this application, a first film layer 11 is disposed between the first electrode layer 10 and the first transport layer 115 of the perovskite cell, and a first film layer 11 is disposed between the second transport layer 117 and the second electrode layer 12, forming a double-layer self-healing functional film layer structure, which can better improve the effect of sunlight concentration on the light-receiving surface of the solar cell 1, thereby improving the light flux and the light conversion efficiency.

[0101] Figure 8 It is a schematic structural diagram of the first film layer in a damaged state of the solar cell provided in an embodiment of this application. Figure 9The figure is a schematic diagram of the first film layer of the solar cell provided in an embodiment of the present application in a state where the damage repair is completed. The solar cell 1 includes a functional layer 14 and a first film layer 11 located on one side of the functional layer 14. The first film layer 11 is a self-healing functional film layer. As Figure 8 shown, cracks 113 appear in the first film layer 11, and ions 111 escape into the functional layer 14, triggering the repair instinct of the first film layer 11. The first film layer 11 immediately performs self-repair until the first film layer 11 is repaired, presenting a state where the damage repair is completed as shown in Figure 9 to prevent the escape of ions 111 caused by defects in the solar cell 1.

[0102] In some embodiments, the first film layer 11 is made of a self-healing material. It should be understood that damaged tissues in organisms can achieve cell proliferation and reconstruction through the migration of adjacent cells, so that the damage can heal itself, such as the automatic stoppage of blood flow after a finger injury; the formation of new tissues in tree bark, etc. Self-healing materials, also known as self-healing materials, can repair themselves through chemical reactions or reach a stable phase after being damaged, so that they still have the same excellent performance as the original materials even after being repaired or repaired multiple times.

[0103] Exemplarily, self-healing materials can be classified into two categories according to the triggering mode: automatic repair and non-automatic repair triggered by external heat, light, electricity, etc.; and automatic repair materials can be further divided into foreign-aid type self-healing materials and intrinsic type self-healing materials.

[0104] Exemplarily, foreign-aid type self-healing materials mainly complete self-healing behavior by adding other materials, namely repair agents. In the material system, once the self-healing behavior occurs, the repair agent cannot return to the monomer state. Therefore, foreign-aid type self-healing materials can only be repaired a limited number of times, and the repair effect gradually decreases after the same part is damaged.

[0105] Exemplarily, intrinsic type self-healing materials mainly rely on reversible covalent bonds and / or non-covalent bonds existing in the system to complete the self-healing of the materials. In the self-healing system, since there is no introduction of repair agents, the generation of phase interfaces in the materials is avoided, which improves the repair efficiency of the materials and the materials can be repaired multiple times. And the different interactions in the repair materials will also have different effects on the performance of the repaired materials. Relatively speaking, the valence bond force of reversible covalent bonds is stronger, and the performance of the repaired materials is more stable. Currently, the systems used for self-healing include reversible structures such as hydrogen bonds, electrostatic interactions, host-guest interactions, imine bonds, disulfide bonds, double network structures, coordination bonds, and Diels-Alder reactions.

[0106] In some embodiments, the first film layer 11 is made of an intrinsic self-healing material. Compared with extrinsic repair materials, intrinsic self-healing materials have better performance and effects. Taking hydrogen bonds as an example, hydrogen bonds are a relatively common intermolecular interaction. When H is covalently bonded to an atom with high electronegativity and small radius, a force is generated between this hydrogen atom and another atom. Due to the dynamic reversible nature of hydrogen bonds, they can be used in the preparation of self-healing materials.

[0107] For the solar cell provided by the embodiment of the present application, the first film layer 11 has self-healing ability, which solves the ion escape caused by defects in the battery film layer and improves the stability of the battery.

[0108] Figure 10 It is a schematic structural diagram of a solar cell provided in another embodiment of the present application. As Figure 10 shown, the solar cell 1 further includes a first encapsulation layer 300. The second electrode layer 12 is located on the side of the first electrode layer 10 away from the substrate 100. The first encapsulation layer 300 is disposed on the surface of the second electrode layer 12 away from the substrate 100 and covers both side surfaces of the solar cell 1 and is connected to the substrate 100.

[0109] Preferably, the material of the first encapsulation layer 300 includes any one or a combination of alumina and silica.

[0110] Exemplarily, the material of the first encapsulation layer 300 can be alumina, and the first encapsulation layer 300 is prepared by atomic layer deposition. Specifically, the two reaction gases are trimethylaluminum (Al(CH3)3) carried by nitrogen (N2, purity ≥ 99.999%) and water (H2O). The two are alternately charged into the reaction chamber in the form of pulses. The pulse time is preferably 0.015 s, the residence time is 60 s, and one cycle is one alternation. 100 - 200 cycles are used to prepare alumina layers with different thicknesses, preferably 120 times, to obtain a first encapsulation layer 300 with a thickness of 20 - 25 nm. Additionally, it can also be further encapsulated in combination with conventional encapsulation materials such as EVA, ultraviolet encapsulation glue, and silicone rubber.

[0111] It should be understood that the first encapsulation layer 300 can also adopt thin film encapsulation (TFE).

[0112] For the solar cell provided by the embodiment of the present application, the first encapsulation layer 300 is disposed on the surface of the second electrode layer 12 away from the substrate 100 and covers both side surfaces of the solar cell 1 and is connected to the substrate 100, which can play the role of blocking water and oxygen and further improve the stability of the solar cell.

[0113] At present, most perovskite-silicon tandem solar cells use silicon-based solar cells with a planar structure or a pyramid-textured surface structure. The silicon-based solar cells with a planar structure have serious reflection at the perovskite-silicon interface and strongly depend on the wavelength and angle of incident light, which limits its energy conversion efficiency in actual operation. In addition, the flat structure also requires polishing treatment, increasing the production cost. It is difficult for the silicon-based solar cells with a pyramid-textured surface structure to achieve good coverage of solution-processed perovskite, and a vacuum preparation process is required. The preparation conditions are harsh, and it is difficult to implement the passivation of perovskite additives and the regulation of stability. Even if the solution process can be achieved by reducing the pyramid size and increasing the perovskite thickness on the pyramid-textured surface, reducing the pyramid size will affect the optical performance, and increasing the perovskite thickness will lead to a decrease in cell performance due to insufficient carrier diffusion length.

[0114] Figure 11 This is a schematic structural diagram of a tandem solar cell provided in an embodiment of the present application. As Figure 11 shown, the embodiment of the present application provides a tandem solar cell 2, which includes a first cell 21 and a second cell 22 arranged in a stack, and at least one of the first cell 21 and the second cell 22 is the solar cell mentioned in any of the above embodiments.

[0115] Exemplarily, a first film layer is provided between the electrode layer and the functional layer of the first cell 21 and / or the second cell 22, and the function of the first film layer includes increasing the optical path.

[0116] The tandem solar cell provided in the embodiment of the present application, the tandem solar cell 2 includes a first cell 21 and a second cell 22 arranged in a stack, and at least one of the first cell 21 and the second cell 22 is a solar cell provided with a first film layer. The function of the first film layer includes increasing the optical path, which can change the interface to reduce reflection loss, and can further increase the optical path of the incident light by improving the scattering ability of the incident light, effectively improving the light absorption ability of the tandem solar cell 2 and solving the problem of how to improve the light conversion efficiency of the tandem solar cell 2.

[0117] Figure 12a This is a schematic structural diagram of a tandem solar cell provided in another embodiment of the present application. As Figure 12a shown, the first cell 21 includes a perovskite solar cell, and the second cell 22 includes a silicon-based solar cell. The perovskite solar cell is arranged in a stack on the side of the silicon-based solar cell away from the substrate 100.

[0118] Figure 12b This is a schematic structural diagram of a tandem solar cell provided in another embodiment of the present application. As Figure 12bAs shown, the tandem solar cell 2 includes a second encapsulation layer 301 which encapsulates the perovskite solar cell and the silicon-based solar cell, and the second encapsulation layer 301 is connected to the substrate 100. The material of the second encapsulation layer 301 includes any one or a combination of multiple ones of aluminum oxide and silicon oxide.

[0119] Among them, the first cell 21 includes a first electrode layer 10, a first film layer 11, a first transport layer 115, a photoactive layer 116, a second transport layer 117, a first film layer 11, and a second electrode layer 12 which are sequentially stacked. Both the first electrode layer 10 and the second electrode layer 12 are transparent electrode layers.

[0120] Among them, the second cell 22 includes a first electrode layer 10, a second film layer 15, a first film layer 11, an n-type silicon layer 130 / n-type polycrystalline silicon (poly-Si), a first i-type silicon layer / tunneling oxide layer 132, a c-type silicon layer 133, a second i-type silicon layer / p+ emitter 134, a p-type silicon layer 131 / aluminum oxide (Al2O3) passivation layer, a first film layer 11, a second film layer 15, and a second electrode layer 12.

[0121] In some embodiments, the material of the second encapsulation layer 301 can be aluminum oxide, and the second encapsulation layer 301 is prepared by atomic layer deposition. Of course, thin film encapsulation (TFE) can also be used.

[0122] In addition, the organic-inorganic hybrid two-dimensional perovskite battery has excellent optoelectronic properties, crystallinity and stability. Compared with the three-dimensional perovskite battery, due to the introduction of organic spacer cations (OSC), a unique layered crystal structure is formed, endowing the two-dimensional perovskite material with special properties: (1) The multi-layer quantum well structure contributes to the anisotropic optoelectronic properties of the material; (2) The spacer cations change the precursor cluster state, realizing high-quality crystallization in solution; (3) The hydrophobic property and the ion migration inhibition effect of the spacer layer improve the stability of the perovskite from the source. Therefore, the first cell used in the tandem solar cell 2 of the embodiment of the present application is a two-dimensional perovskite battery, which has remarkable stability compared with the three-dimensional perovskite battery and can improve the overall reliability of the device. Of course, the first cell can also use a three-dimensional perovskite battery.

[0123] The tandem solar cell provided by the embodiment of the present application has a perovskite solar cell stacked on top of a silicon-based solar cell. The perovskite solar cell and the silicon-based solar cell are combined in a mechanical stacking manner to form a tandem cell. The perovskite solar cell and the silicon-based solar cell in the tandem cell can work independently without interference. Moreover, since the mechanical stacking method is used, the process conflict between the first cell and the second cell is avoided, and the bottom second cell is also prevented from being damaged during the preparation of the first cell. In addition, the tandem solar cell 2 includes a second encapsulation layer 301, and the second encapsulation layer 301 can block water and oxygen, further improving the stability of the tandem cell.

[0124] Figure 12c It is a schematic structural diagram of the tandem solar cell provided in another embodiment of the present application. As Figure 12c shown, the tandem solar cell 2 includes a first cell 21 and a second cell 22 stacked on top of each other, and both the first cell 21 and the second cell 22 include perovskite solar cells.

[0125] Figure 12d It is a schematic structural diagram of the tandem solar cell provided in another embodiment of the present application. As Figure 12d shown, the tandem solar cell 2 includes a second encapsulation layer 301. The second encapsulation layer 301 covers the upper and lower perovskite solar cells, and the second encapsulation layer 301 is connected to the substrate 100. The material of the second encapsulation layer 301 includes any one or a combination of alumina and silica.

[0126] Figure 13 Shown is a schematic flow diagram of the method for preparing a solar cell provided in an embodiment of the present application. As Figure 13 shown, the method for preparing the solar cell includes the following steps.

[0127] Step 1000: Provide a substrate.

[0128] Step 1001: Prepare a first electrode layer on one side of the substrate.

[0129] Step 1002: Coat a transparent polymer material containing scattering particles on the surface of the first electrode layer to obtain a first film layer.

[0130] After the first electrode layer is fabricated, a self-healing functional film layer with scattering particles, i.e., the first film layer, is formed on this surface. The material of the first film layer can be an organic material. The first film layer needs to possess three elements: high transparency, with white scattering particles, and having a self-healing function. The transparency requirement is above 80%. The scattering particles are white particles, which have advantages such as high refractive index, low scattering, high transmittance, and high temperature stability. The scattering particles can be zirconia. The self-healing functional layer includes transparent polymer materials that self-heal using hydrogen bonds or nitroxide radicals, and transparent polymer materials that self-heal using the Diels-Alder reaction, etc. The preparation process of the first film layer can be achieved through an inkjet printing process, followed by curing after printing, or can also be through coating methods such as Slit.

[0131] Step 1003, prepare a functional layer on the surface of the first film layer.

[0132] Step 1004, prepare a second electrode layer on the functional layer to obtain a solar cell.

[0133] Among them, the solar cell is a silicon-based solar cell, and the functional layer includes an n-type silicon layer, a first i-type silicon layer, a c-type silicon layer, a second i-type silicon layer, and a p-type silicon layer arranged in layers; the solar cell is a perovskite cell, and the functional layer includes a first transport layer, a photo-conversion layer, and a second transport layer arranged in layers.

[0134] The preparation method of the solar cell provided by the embodiments of the present application prepares a first film layer between the electrode layer and the functional layer. The first film layer is a transparent polymer material doped with scattering particles, which can change the interface to reduce reflection loss, and can further increase the optical path of the incident light by improving the scattering ability of the incident light, effectively improving the light absorption ability of the solar cell, and solving the problem of how to improve the light conversion efficiency of the solar cell.

[0135] Figure 14 The flowchart of the preparation method of the tandem solar cell provided by an embodiment of the present application is shown. As Figure 14 shown, the preparation method of the tandem solar cell includes the following steps.

[0136] Step 1100, prepare a first solar cell and a second solar cell.

[0137] Step 1111, stack the prepared second solar cell on one side of the pre-prepared first solar cell, and the first solar cell is electrically connected to the second solar cell.

[0138] Preferably, an encapsulation layer is prepared on the outer surfaces of the first solar cell and the second solar cell, and the encapsulation layer is connected to the substrate.

[0139] Specifically, the encapsulation layer can be prepared by atomic layer deposition to achieve the encapsulation of the tandem solar cell.

[0140] At least one of the first solar cell and the second solar cell is the solar cell provided in any of the above embodiments.

[0141] The method for manufacturing a tandem solar cell provided by the embodiments of the present application can block water and oxygen by encapsulating the first solar cell and the second solar cell, improve the self-protection performance of the cell, and further enhance the stability of the tandem solar cell.

[0142] The above description has been given for purposes of illustration and description. In addition, this description is not intended to limit the embodiments of the present application to the forms disclosed herein. Although several example aspects and embodiments have been discussed above, those skilled in the art will recognize some of their variations, modifications, alterations, additions, and sub-combinations.

Claims

1. A solar cell, characterized in that, Comprising: A substrate; An electrode layer and a functional layer stacked on one side of the substrate, a first film layer is provided between the electrode layer and the functional layer, and the function of the first film layer includes increasing the optical path; Wherein, the first film layer includes scattering particles, the scattering particles are uniformly and continuously distributed in the first film layer, and the transparency of the scattering particles is greater than 80%; Wherein, the function of the first film layer includes self-healing, and the first film layer further includes a polymer material for dispersing the scattering particles; The polymer material includes at least one of transparent polymer materials that self-heal by hydrogen bonds, self-heal by nitroxide radicals, and self-heal by Diels-Alder reaction. The number of the first film layers is at least one layer, and multiple first film layers are stacked and / or spaced; The electrode layer includes a first electrode layer and a second electrode layer, and the functional layer is located between the first electrode layer and the second electrode layer; The solar cell further includes a second film layer, the second film layer is a silicon nitride antireflection layer, the second film layer is located between the first electrode layer and the second electrode layer, and the number of the second film layers is at least one layer. The function of the second film layer includes increasing the output power of the solar cell; Wherein, the first film layer is in direct contact with the functional layer to prevent ion escape caused by battery defects; The solar cell further includes a first encapsulation layer, and the first encapsulation layer is disposed on the surface of the second electrode layer away from the substrate; The material of the first encapsulation layer includes any one or a combination of alumina and silica.

2. The solar cell according to claim 1, characterized in that, The first film layer is located between the first electrode layer and the functional layer, and / or the first film layer is located between the second electrode layer and the functional layer.

3. The solar cell according to claim 1, characterized in that, The scattering particles include at least one of zirconia, silica, alumina, titanium dioxide, and zinc oxide.

4. The solar cell according to claim 2, wherein The first film layer is located between the first electrode layer and the functional layer, the second film layer is located between the first film layer and the first electrode layer, and / or the second film layer is located between the functional layer and the second electrode layer.

5. The solar cell according to claim 2, characterized in that, The first film layer is located between the second electrode layer and the functional layer, the second film layer is located between the first film layer and the second electrode layer, and / or the second film layer is located between the functional layer and the first electrode layer.

6. The solar cell according to claim 2, characterized in that, The first film layer is located between the first electrode layer and the functional layer and between the second electrode layer and the functional layer, the second film layer is located between the first film layer and the first electrode layer, and / or the second film layer is located between the first film layer and the second electrode layer.

7. The solar cell according to any one of claims 1 to 6, characterized in that, The solar cell is a silicon-based solar cell, and the functional layer includes a stacked n-type silicon layer, a first i-type silicon layer, a c-type silicon layer, a second i-type silicon layer, and a p-type silicon layer. The first film layer is located between the first electrode layer and the n-type silicon layer, and / or the first film layer is located between the second electrode layer and the p-type silicon layer.

8. The solar cell according to any one of claims 1 to 6, characterized in that, The solar cell is a perovskite solar cell. The functional layer includes a first transport layer, a photo - electric conversion layer, and a second transport layer which are stacked. The first film layer is located between the first electrode layer and the first transport layer, and / or the first film layer is located between the second electrode layer and the second transport layer.

9. The solar cell according to any one of claims 1 to 6, characterized in that, The second electrode layer is located on the side of the first electrode layer away from the substrate, and covers the two side surfaces of the solar cell and is connected to the substrate.

10. A laminated solar cell, characterized in that, It includes a first battery and a second battery which are stacked. At least one of the first battery and the second battery is the solar cell according to any one of claims 1 to 9. The first battery includes a perovskite solar cell, and the second battery includes a silicon - based solar cell.

11. The stacked solar cell according to claim 10, wherein The perovskite solar cell is stacked on the side of the silicon - based solar cell away from the substrate.

12. The stacked solar cell according to claim 10, characterized in that, Both the first battery and the second battery include perovskite solar cells.

13. The stacked solar cell according to claim 10, characterized in that, The stacked solar cell includes a second encapsulation layer. The second encapsulation layer covers the perovskite solar cell and the silicon - based solar cell, and is connected to the substrate.

14. The laminated solar cell according to claim 13, wherein, The material of the second encapsulation layer includes any one or a combination of more of aluminum oxide and silicon oxide.

15. A method for preparing a solar cell, which is used to prepare the solar cell according to any one of claims 1 to 9, characterized in that, It includes: Provide a substrate; Prepare a first electrode layer on one side of the substrate; Coat a transparent polymer material containing scattering particles on the surface of the first electrode layer to obtain a first film layer; Prepare a functional layer on the surface of the first film layer; Prepare a second electrode layer on the functional layer to obtain the solar cell.

16. A method for preparing a stacked solar cell, characterized in that, It includes: Prepare a first solar cell and a second solar cell according to the preparation method of the solar cell as claimed in claim 15; Stack the prepared second solar cell on one side of the prepared first solar cell, and the first solar cell is electrically connected to the second solar cell.

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