Solar cells, photovoltaic modules and power consuming devices

Abstract

The present application relates to a solar cell, a photovoltaic module and a power consumption device, the solar cell includes a plurality of subcells arranged in sequence along a first direction, each of the plurality of subcells includes a first photoelectric conversion layer for photoelectric conversion, the first direction is perpendicular to a thickness direction of the subcells, and along the first direction, there is a negative correlation between the change tendency of the thickness of the first photoelectric conversion layer of each subcell and the change tendency of the cross-sectional area perpendicular to the thickness direction of each first photoelectric conversion layer, so as to improve the uniformity of the output photocurrent and the uniformity of the current among each subcell. The solar cell of the embodiment of the present application can improve the photoelectric conversion efficiency.

Description

[Technical field]

[0001] [CROSS REFERENCE TO RELATED APPLICATIONS] This application claims priority to Chinese patent application No. 202111610614.8, entitled "Solar Cell, Photovoltaic Module and Power Consumption Device," filed on December 27, 2021, the entire contents of which are incorporated herein by reference.

[0002] The present application relates to the technical field of battery production, in particular solar cells, photovoltaic modules and power consuming devices. [Background technology]

[0003] Solar cells are photoelectric conversion devices that directly convert light energy into electrical energy. They have excellent photoelectric properties and are simple to manufacture, bringing new space and hope to photovoltaic power generation.

[0004] During the production process of solar cells, how to increase the photoelectric conversion efficiency has become an urgent issue that needs to be resolved. Summary of the Invention

[0005] The present application provides a solar cell, a photovoltaic module and a power consuming device, which aims to increase the photoelectric conversion efficiency of the solar cell.

[0006] In a first aspect, the present application proposes a solar cell, the solar cell including a plurality of subcells arranged in sequence along a first direction, each of the plurality of subcells including a first photoelectric conversion layer for photoelectric conversion, the first direction being perpendicular to a thickness direction of the subcells, and a change trend of the thickness of the first photoelectric conversion layer of each subcell and a change trend of the cross-sectional area perpendicular to the thickness direction of each first photoelectric conversion layer are negatively correlated along the first direction so as to enhance uniformity of the photocurrent output among each subcell.

[0007] In the above technical solution, along the first direction, there is a negative correlation between the change trend of the thickness of the first photoelectric conversion layer of each subcell and the change trend of the cross-sectional area perpendicular to the thickness direction of each first photoelectric conversion layer, and the photocurrents output and converted by each subcell are substantially consistent, and no current limitation of the solar cell is caused by some subcells among the multiple subcells, so the current output by the entire solar cell is increased and its power is increased, thereby improving the photoelectric conversion efficiency of the solar cell; and since the photocurrents of each subcell are substantially consistent, the risk of heat spot phenomenon occurring in the solar cell can be reduced, and the reliability and safety performance of the solar cell are improved.

[0008] In some embodiments, the thickness of each first photoelectric conversion layer along the first direction has a negative correlation with the dimension of each first photoelectric conversion layer along the first direction. In the present embodiment, each subcell is arranged along the first direction, and in the process of forming each subcell, the dimension of the first photoelectric conversion layer of each subcell along the first direction is simultaneously adjusted, thereby achieving the purpose of adjusting the cross-sectional area, and the adjustment means is simple.

[0009] In some embodiments, the thickness of each of the first photoelectric conversion layers is gradually decreased along the first direction, and the cross-sectional area perpendicular to the thickness direction of each of the first photoelectric conversion layers is gradually increased along the first direction. In the present embodiment, the change trend of the cross-sectional area perpendicular to the thickness direction of each of the first photoelectric conversion layers is negatively correlated with the change trend of the thickness, and the uniformity of the photocurrent converted and output by each subcell can be adjusted.

[0010] In some embodiments, the dimension of each first photoelectric conversion layer along the first direction gradually increases, and the cross-sectional area perpendicular to the thickness direction of each of the first photoelectric conversion layers gradually increases. In the embodiments of the present application, by increasing the dimension of each first photoelectric conversion layer along the first direction, the cross-sectional area perpendicular to the thickness direction of each of the first photoelectric conversion layers is increased, and the means for adjusting the cross-sectional area is simple.

[0011] In some embodiments, the solar cell includes a plurality of dead zones between two adjacent subcells to realize electrical connection between the two adjacent subcells, and along the first direction, the change tendency of the thickness of the first photoelectric conversion layer of each subcell and the change tendency of the cross-sectional area perpendicular to the thickness direction of each dead zone are positively correlated. In the embodiment of the present application, the larger the cross-sectional area perpendicular to the thickness direction of the dead zone, the larger the series connection resistance formed thereby, and the smaller the cross-sectional area perpendicular to the thickness direction of the dead zone, the smaller the series connection resistance formed thereby. The first photoelectric conversion layer of the thick subcell has a strong absorption ability for incident light, and in combination with a large in-line (series) connection, the photocurrent of the subcell can be relatively reduced, and the first photoelectric conversion layer of the thin subcell has a weak absorption ability for light, and in combination with a small in-line (series) connection, the photocurrent of the subcell can be relatively increased, so that the photocurrent output by each subcell is substantially the same, i.e., the uniformity is enhanced.

[0012] In some embodiments, the thickness of each first photoelectric conversion layer is gradually reduced along the first direction, and the cross-sectional area perpendicular to the thickness direction of each dead zone is gradually reduced along the first direction. In the present embodiment, the variation trend of the cross-sectional area perpendicular to the thickness direction of each dead zone is positively correlated with the variation trend of the thickness, thereby adjusting the uniformity of the photocurrent converted and output by each subcell.

[0013] In some embodiments, the dimension of each dead zone along the first direction is tapered such that the cross-sectional area of ​​each dead zone along the thickness direction is tapered. In some embodiments of the present application, the dimension of each dead zone along the first direction is tapered to reduce the cross-sectional area of ​​each dead zone along the thickness direction, and the means for adjusting the cross-sectional area is simple.

[0014] In some embodiments, each of the dead zones includes a first electrode layer, a second photoelectric conversion layer, a second electrode layer, and a through-hole. The second photoelectric conversion layer includes a first main body portion located on the surface of the first electrode layer, and a first connection portion connected to the first main body portion and connecting the first main body portion and the first electrode layer, the second electrode layer includes a first body portion located on a surface of the second photoelectric conversion layer away from the first electrode layer, and a first extension portion connecting the first body portion and the first electrode layer, the through-hole extends through the first body portion to a surface of the first electrode layer close to the second photoelectric conversion layer, and the dimension in the first direction of at least one of the first connection portion, the first extension portion, and the through-hole becomes gradually smaller along the first direction. In an embodiment of the present application, the cross-sectional area perpendicular to the thickness direction of the dead zone is adjusted by adjusting the dimension in a first direction of at least one of the first connection portion, the first extension portion, and the through-hole portion, and the means for adjusting the cross-sectional area is simple.

[0015] In some embodiments, the subcell further comprises an electron transport layer connected to the first photovoltaic layer for transporting electrons, and / or the subcell further comprises a hole transport layer connected to the first photovoltaic layer for transporting holes. In some embodiments, the electron transport layer and / or the hole transport layer can increase the photovoltaic conversion efficiency of the solar cell.

[0016] In a second aspect, an embodiment of the present application further provides a photovoltaic module including a solar cell according to an embodiment of the first aspect of the present application.

[0017] In a third aspect, embodiments of the present application further provide a power consuming device including a photovoltaic module according to embodiments of the second aspect of the present application. [Brief description of the drawings]

[0018] In order to more clearly describe the technical solutions of the embodiments of the present application, the drawings that need to be used in the embodiments of the present application are briefly described below. Obviously, the drawings described below are only some embodiments of the present application, and those skilled in the art can obtain further drawings based on the drawings without creative efforts. [Figure 1] 1 is a structural schematic diagram of a vehicle provided according to some embodiments of the present application. [Diagram 2] FIG. 1 is a schematic block diagram of a photovoltaic module provided in accordance with some embodiments of the present application. [Diagram 3] 1 is a structural schematic diagram of a solar cell provided in accordance with some embodiments of the present application; [Figure 4] FIG. 4 is an enlarged schematic diagram of the structure of a dead zone of the solar cell shown in FIG. 3.

[0019] In the drawing section, the drawings are not necessarily drawn to scale. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] In order to make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application are described below with reference to the drawings of the embodiments of the present application. It is clear that the described embodiments are only a part of the embodiments of the present application, and are not all of the embodiments. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative efforts are all within the scope of protection of the present application.

[0021] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by those skilled in the art. The terms used in this application are only for describing specific embodiments and are not intended to limit this application. The terms "include", "have" and any variations thereof in this application's specification, claims and drawings are intended to cover non-exclusive "include". The terms "first", "second", etc. in this application's specification, claims and drawings are intended to distinguish different objects and are not intended to describe a specific order or a main-subordinate relationship.

[0022] When referring to an "embodiment" in this application, it means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of this application. The appearances of this phrase in various places in the specification do not necessarily all refer to the same embodiment, nor are they mutually exclusive independent or alternative embodiments of other embodiments.

[0023] In the description of this application, unless otherwise specified or limited, the terms "attach," "connect," "join," and "couple" should be understood in a broad sense, and may refer to, for example, a fixed connection, a detachable connection, or an integral connection, a direct connection, an indirect connection via an intermediate medium, or internal communication between two elements. A person skilled in the art can understand the specific meaning of the above terms in the present application according to the specific circumstances.

[0024] The term "and / or" in this application merely describes the relationship between related objects and indicates that three relationships may exist, for example, A and / or B can represent three cases: A alone, A and B in combination, and B alone. Also, the character " / " in this application generally indicates that the related objects before and after it are in an "or" relationship.

[0025] In the embodiments of the present application, the same reference numerals represent the same elements, and for the sake of brevity, detailed descriptions of the same elements in different embodiments will be omitted. It should be understood that the dimensions of each element in the embodiments of the present application, such as thickness, length, width, etc., and the overall dimensions of the integrated device, such as thickness, length, width, etc., shown in the drawings, are merely illustrative and do not impose any limitations on the present application.

[0026] As used herein, "plurality" means two or more (including two).

[0027] In the embodiment of the present application, the solar cell is a photovoltaic device that converts light energy directly into electrical energy based on the photovoltaic effect. Different materials are used in the photovoltaic device, and a built-in electric field is formed inside the photovoltaic device due to the difference in the quasi-Fermi levels of the different materials. Under light irradiation, photons with high energy are absorbed and photogenerated carriers (electron-hole pairs) are excited. Since the types of charges are different, the electrons and holes drift in opposite directions due to the action of the built-in electric field, and the electrons move to the negative electrode and the holes move to the positive electrode, forming a potential difference between the positive and negative electrodes and generating a current.

[0028] A solar cell includes a photoelectric conversion layer for photoelectric conversion, and for a photoelectric conversion layer made of a specific material, its light absorption coefficient is a fixed value, and there is a positive correlation between the thickness of the photoelectric conversion layer and the degree of absorption of light by the photoelectric conversion layer, and since the degree of absorption of light by the photoelectric conversion layer determines the magnitude of the photocurrent that can be converted and output, there is a positive correlation between the thickness of the photoelectric conversion layer and the photocurrent. The thicker the photoelectric conversion layer, the larger the photocurrent that can be converted and output, and the higher the photoelectric conversion efficiency, and the smaller the thickness, the smaller the photocurrent that can be converted and output, and the lower the photoelectric conversion efficiency.

[0029] The inventors have found that when a solar cell is divided into a plurality of subcells, each subcell is usually divided into equal widths, and the equal width division means that each subcell has the same width and each dead zone has the same width. However, when a photoelectric conversion layer is manufactured, the thickness of the photoelectric conversion layer is not uniform due to limitations of the manufacturing process, that is, the thickness of some areas may be large while the thickness of other areas may be small. In areas with large thickness, the photocurrent that can be converted and output by the subcell is large, and in areas with small thickness, the photocurrent that can be converted and output by the subcell is small. Therefore, the magnitude of the photocurrent that can be output by each subcell is not the same due to the difference in thickness, and when each subcell is connected in series, the subcell with a small output photocurrent will cause current limiting of the entire solar cell, the current of the entire solar cell will be small, and the photoelectric conversion efficiency of the solar cell will be further reduced. In addition, the magnitude of the photocurrent that can be output by each subcell is not the same, and the temperature distribution of the entire solar cell is not uniform, which makes it easy to generate a risk of damage due to the heat spot effect.

[0030] Based on the above problem, the inventor proposes a technical solution, in which the width between each subcell is designed according to the thickness of the first photoelectric conversion layer of each subcell, so that along the first direction, the change tendency of the thickness of the first photoelectric conversion layer of each subcell and the change tendency of the cross-sectional area perpendicular to the thickness direction of each first photoelectric conversion layer are negatively correlated, so that the magnitude of the photocurrent generated between each subcell is substantially consistent. In a solar cell having such a structure, the current of each subcell is equivalent and the same, and does not substantially cause the current limit of the entire solar cell, so that the photoelectric conversion efficiency of the solar cell can be improved, and since the photocurrent of each subcell is substantially the same, the risk of the heat spot phenomenon occurring in the solar cell can be reduced, and the reliability and safety performance of the solar cell can be improved.

[0031] The technical solutions described in the embodiments of the present application are applied to photovoltaic modules including solar cells and power consuming devices using the photovoltaic modules.

[0032] The power consuming device may be a vehicle, a mobile phone, a portable device, a laptop computer, a ship, a spacecraft, an electric toy, a power tool, etc. The vehicle may be a gasoline-powered automobile, a gas-powered automobile, or a new energy automobile, the spacecraft may include an airplane, a rocket, a space shuttle, a spaceship, etc., the electric toy may include a stationary or mobile electric toy, such as a game console, an electric car toy, an electric propulsion ship toy, or an electric plane toy, and the power tool may include a metal cutting power tool, such as an electric drill, an electric grinder, an electric wrench, an electric screwdriver, an electric hammer, an electric impact drill, a concrete vibrator, or an electric planer, a polishing power tool, a mounting power tool, or a railroad power tool. In the embodiments of the present application, the power consuming device is not particularly limited.

[0033] In the following embodiments, for ease of explanation, a case will be described in which the power consuming device is a vehicle.

[0034] 1 is a structural schematic diagram of a vehicle provided by some embodiments of the present application. As shown in FIG. 1, a photovoltaic module 2 is provided inside the vehicle 1, and the photovoltaic module 2 may be provided on the top, front, or rear of the vehicle 1. The photovoltaic module 2 can be used to power the vehicle 1, for example, the photovoltaic module 2 can be the operating power source of the vehicle 1.

[0035] The vehicle 1 may further include a controller 3 and a motor 4, where the controller 3 is used to control the photovoltaic module 2 to power the motor 4, for example to meet the operating power needs of the vehicle 1 for starting, navigation and running.

[0036] In some embodiments of the present application, the photovoltaic module 2 can be used not only as the operating power source for the vehicle 1, but also as the driving power source for the vehicle 1, providing driving power to the vehicle 1 in place of, or in place of, gasoline or natural gas.

[0037] 2 is a schematic block diagram of a photovoltaic module provided by some embodiments of the present application. As shown in FIG. 2, the photovoltaic module 2 includes a solar cell 5. The solar cell 5 may be one or more. When the solar cell 5 is multiple, the multiple solar cells 5 may be connected in series, in parallel, or in series-parallel, and the series-parallel connection means that the multiple solar cells 5 include both series and parallel connections, and can provide high voltage and capacity.

[0038] FIG. 3 is a structural schematic diagram of a solar cell provided according to some embodiments of the present application.

[0039] As shown in FIG. 3 , the solar cell 5 provided by the embodiment of the present application includes a plurality of subcells 6, which are arranged in sequence along a first direction Y. Each of the subcells 6 includes a first photoelectric conversion layer 521 for photoelectric conversion. In order to enhance the uniformity of the photocurrent output among each subcell 6, there is a negative correlation between the change tendency of the thickness of the first photoelectric conversion layer 521 of each subcell 6 and the change tendency of the cross-sectional area perpendicular to the thickness direction X of each first photoelectric conversion layer 521 along the first direction Y.

[0040] The solar cell 5 includes a plurality of subcells 6 connected in series, and the plurality of subcells 6 can increase the voltage and capacity of the solar cell 5. The plurality of subcells 6 are arranged in sequence along a first direction Y, which may be a width direction or a length direction of the subcells 6. The X direction shown in Fig. 3 represents the thickness direction of the subcells 6, and the Y direction represents the first direction, where the first direction Y is perpendicular to the thickness direction X.

[0041] The first photoelectric conversion layer 521 is a core functional layer of the subcell 6, and its main role is to absorb external light and then form electron-hole pairs therein, and to separate and extract the electrons and holes for output to the outside. Exemplarily, the first photoelectric conversion layer 521 may include a perovskite photoelectric conversion layer, a cadmium zinc telluride photoelectric conversion layer, a copper indium gallium selenide photoelectric conversion layer, a copper indium selenide photoelectric conversion layer, or a copper indium gallium sulfur photoelectric conversion layer.

[0042] In the solar cell 5, the thickness of the first photoelectric conversion layer 521 of each subcell 6 along the first direction Y is not uniform due to limitations imposed by the manufacturing process when forming the first photoelectric conversion layer 521 of each subcell 6, and the thickness tends to vary. Specifically, the thickness variation tendency may be gradually decreasing or gradually increasing along the first direction Y, or may be increasing and then decreasing along the first direction Y, or may be decreasing and then increasing along the first direction Y. In the embodiment of the present application, the thickness variation tendency may be a linear change or a nonlinear change, and the embodiment of the present application is not limited thereto.

[0043] There is a positive correlation between the thickness of the first photoelectric conversion layer 521 and its degree of light absorption: the greater the thickness, the greater the degree of light absorption and the larger the photocurrent converted and output by the subcell 6, and the smaller the thickness, the smaller the degree of light absorption and the smaller the photocurrent converted and output by the subcell 6. When the first photoelectric conversion layer 521 of each subcell 6 has a certain thickness variation trend, the magnitude of the photocurrent output by each subcell 6 also shows a corresponding variation trend.

[0044] When the thickness of the first photoelectric conversion layer 521 is a constant value, the photoelectric conversion area and the photocurrent of the first photoelectric conversion layer 521 are positively correlated. The photoelectric conversion area refers to the area where the first photoelectric conversion layer 521 can effectively use light to perform photoelectric conversion, and is specifically the cross-sectional area perpendicular to the thickness direction X of the first photoelectric conversion layer 521. The larger the photoelectric conversion area, the larger the amount of absorbable light energy, and the larger the photocurrent converted and output by the first photoelectric conversion layer 521. The smaller the photoelectric conversion area, the smaller the amount of absorbable light energy, and the smaller the photocurrent output by the first photoelectric conversion layer 521. In the embodiment of the present application, the photoelectric conversion area is adjusted according to the thickness of the first photoelectric conversion layer 521, thereby achieving effective control of the photocurrent of each subcell 6. In other words, when the thickness of the first photoelectric conversion layer 521 is relatively large, the absorption ability for incident light is strong, and by adopting a small photoelectric conversion area and combining with a reduced light-receiving area, the photocurrent of the subcell can be relatively reduced, and when the thickness of the first photoelectric conversion layer 521 is relatively small, the absorption ability for incident light is weak, and by adopting a large photoelectric conversion area and combining with an increased light-receiving area, the photocurrent of the subcell can be relatively increased, thereby adjusting the photocurrent output by each subcell 6 to be substantially the same, that is, improving the uniformity. The uniformity specifically refers to the magnitude of the photocurrent output by each subcell being substantially the same.

[0045] In the embodiment of the present application, there is a negative correlation between the change tendency of the thickness of the first photoelectric conversion layer 521 of each subcell 6 along the first direction Y and the change tendency of the cross-sectional area perpendicular to the thickness direction X of each first photoelectric conversion layer 521. That is, by combining a first photoelectric conversion layer 521 having a relatively large thickness with a relatively small photoelectric conversion area, and combining a first photoelectric conversion layer 521 having a relatively small thickness with a relatively large photoelectric conversion area, the uniformity of the photocurrent converted and output between each subcell 6 is adjusted. The temperature distribution of the entire solar cell 5 can be made uniform, the risk of heat spots occurring in the solar cell 5 can be reduced, and the reliability and safety performance of the solar cell 5 can be improved, while the current limit caused by some of the subcells 6 can be avoided, and the current of the entire solar cell 5 can be increased, thereby improving the photoelectric conversion efficiency of the entire solar cell 5.

[0046] The cross-sectional area of ​​the first photoelectric conversion layer 521 perpendicular to the thickness direction X is the product of the width and length of the first photoelectric conversion layer 521. By adjusting the width and / or length of the first photoelectric conversion layer 521, the cross-sectional area of ​​the first photoelectric conversion layer 521 perpendicular to the thickness direction X can be adjusted.

[0047] Continuing to refer to FIG. 3, in some embodiments, there is a negative correlation between the thickness change tendency of each first photoelectric conversion layer 521 along the first direction Y and the dimension change tendency of each first photoelectric conversion layer 521 along the first direction Y. Each subcell 6 is arranged along the first direction Y, and in the process of forming each subcell 6, the dimension size of each subcell 6 along the first direction Y of the first photoelectric conversion layer 521 can be simultaneously adjusted to achieve the purpose of adjusting the cross-sectional area size perpendicular to the thickness direction X of the first photoelectric conversion layer 521.

[0048] The thickness of the first photoelectric conversion layer 521 may vary depending on the specific manufacturing process. Regardless of the thickness of the first photoelectric conversion layer 521, the cross-sectional area of ​​each first photoelectric conversion layer 521 perpendicular to the thickness direction X is negatively correlated with the thickness, thereby adjusting the uniformity of the photocurrent converted and output by each subcell 6.

[0049] As some examples, along the first direction Y, the thickness of each first photoelectric conversion layer 521 gradually decreases, and the cross-sectional area perpendicular to the thickness direction X of each first photoelectric conversion layer 521 gradually increases. Specifically, along the first direction Y, the dimension of each first photoelectric conversion layer 521 along the first direction Y gradually increases.

[0050] As another example, along the first direction Y, the thickness of each first photoelectric conversion layer 521 gradually increases, and the cross-sectional area perpendicular to the thickness direction X of each first photoelectric conversion layer 521 gradually decreases. Specifically, along the first direction Y, the dimension of each first photoelectric conversion layer 521 along the first direction Y gradually decreases.

[0051] As yet another example, the thickness of each first photoelectric conversion layer 521 gradually increases and then gradually decreases along the first direction Y, and the thickness tends to be thin on both sides and thick in the center. When the thickness gradually increases, the cross-sectional area perpendicular to the thickness direction X of each first photoelectric conversion layer 521 gradually decreases, specifically, the dimension of each first photoelectric conversion layer 521 along the first direction Y gradually decreases along the first direction Y, and when the thickness gradually decreases, the cross-sectional area perpendicular to the thickness direction X of each first photoelectric conversion layer 521 gradually increases, specifically, the dimension of each first photoelectric conversion layer 521 along the first direction Y gradually increases along the first direction Y.

[0052] As yet another example, the thickness of each first photoelectric conversion layer 521 gradually decreases and then gradually increases along the first direction Y, and the thickness tends to be thick on both sides and thin in the center. When the thickness gradually decreases, the cross-sectional area perpendicular to the thickness direction X of each first photoelectric conversion layer 521 gradually increases, specifically, the dimension of each first photoelectric conversion layer 521 along the first direction Y gradually increases along the first direction Y, and when the thickness gradually increases, the cross-sectional area perpendicular to the thickness direction X of each first photoelectric conversion layer 521 gradually decreases, and the dimension of each first photoelectric conversion layer 521 along the first direction Y gradually decreases along the first direction Y.

[0053] 3 shows that the thickness of the first photoelectric conversion layer 521 tends to be thin on both sides and thick in the center along the first direction Y. Illustratively, the multiple subcells 6 include at least a first subcell 6a and a second subcell 6b, and the thickness of the first photoelectric conversion layer 521 in the first subcell 6a is greater than the thickness of the first photoelectric conversion layer 521 in the second subcell 6b. Accordingly, when the dimension of the first photoelectric conversion layer 521 in the first subcell 6a along the first direction Y is D1 and the dimension of the first photoelectric conversion layer 521 in the second subcell 6b along the first direction Y is D2, D1 is smaller than D2.

[0054] 3, the solar cell 5 of the embodiment of the present application includes a substrate 50, a first electrode layer 51, a photoelectric conversion layer 52, and a second electrode layer 53, which are stacked in order along its thickness direction X. The polarities of the first electrode layer 51 and the second electrode layer 53 are opposite, and the first electrode layer 51 and the second electrode layer 53 are used to extract a current.

[0055] In some embodiments, the method for manufacturing the solar cell 5 includes the steps of providing a substrate 50, forming a first electrode layer 51 on the substrate 50, and performing a first scribing process on the first electrode layer 51 to form a first openwork portion P1 penetrating the first electrode layer 51 in the first electrode layer 51, and forming a photoelectric conversion layer 52 on a side of the first electrode layer 51 that is away from the substrate 50, and performing a second scribing process on the photoelectric conversion layer 52. the step of forming a plurality of second openwork portions P2 in the photoelectric conversion layer 52; forming a second electrode layer 53 extending into the second openwork portion P2 on the side of the photoelectric conversion layer 52 facing away from the substrate 50, and performing a third scribing on the second electrode layer 53 and the photoelectric conversion layer 52 to form a plurality of third openwork portions P3 in the second electrode layer 53 and the photoelectric conversion layer 52, thereby obtaining a plurality of subcells 6 connected in series.

[0056] In some embodiments, in order to improve the electron transport efficiency, each subcell 6 of the solar cell 5 can include an electron transport layer connected to the photovoltaic conversion layer 52, which is used to transport electrons and can block the transport of holes, and can reduce the recombination of electrons and holes to improve the photovoltaic conversion efficiency.

[0057] In some embodiments, in order to improve the hole transport efficiency, each subcell 6 of the solar cell 5 can include a hole transport layer connected to the photoelectric conversion layer 52, which is used to transport holes and can block the transport of electrons, and can reduce the recombination of holes and electrons to improve the photoelectric conversion efficiency.

[0058] The structure of the solar cell 5 will be specifically described below using as an example a case where the solar cell 5 is a perovskite solar cell. The perovskite solar cell may have a cis structure (nip) or a trans structure (pin).

[0059] The cis-structure perovskite solar cell includes a transparent conductive electrode, an electron transport layer, a perovskite photoelectric conversion layer, a hole transport layer, and a metal electrode, which are stacked in order along the thickness direction of the solar cell. For example, the transparent conductive electrode includes indium tin oxide ITO or fluorine-doped tin oxide FTO. The electron transport layer includes a titanium oxide layer, etc. The hole transport layer includes 2,2',7,7'-tetrakis[N,N-bis(4-methoxyphenyl)amino]-9,9'-spirobifluorene (Spiro-OMeTAD), etc. The metal electrode includes a gold layer, a silver layer, or an aluminum layer.

[0060] The transformer-structured perovskite solar cell includes a transparent conductive electrode, a hole transport layer, a perovskite photoelectric conversion layer, an electron transport layer, and a metal electrode, which are stacked in order along the thickness direction of the solar cell. Exemplarily, the transparent conductive electrode includes an indium tin oxide ITO layer or a fluorine-doped tin oxide FTO layer. The hole transport layer includes a PEDOT:PSS layer, where PEDOT represents a polymer of EDOT (3,4-ethylenedioxythiophene monomer), and PSS represents polystyrene sulfonic acid. The electron transport layer includes a fullerene derivative ([6,6]-phenyl-C61-butyric acid methyl ester) layer or a C60 layer. The metal electrode includes a gold layer, a silver layer, or an aluminum layer. The manufacturing process of the solar cell 5 having such a structure is relatively simple.

[0061] As an example of the production of a transformer-structure perovskite solar cell, the specific production process is as follows. A substrate is provided. A transparent conductive electrode is formed on the surface of the substrate by magnetron sputtering or chemical means. A first scribing is performed by employing means of laser scribing, masking or exposure to form a first openwork portion in the transparent conductive electrode that penetrates the plurality of transparent conductive electrodes. A hole transport layer is formed on the surface of the transparent conductive electrode that faces away from the substrate by means of magnetron sputtering, chemical vapor deposition, atomic layer deposition (ALD) or coating. A perovskite photoelectric conversion layer is formed on the surface of the hole transport layer opposite to the substrate by means of painting, spray coating, spin coating, vapor deposition or chemical deposition. An electron transport layer is formed on the surface of the perovskite photoelectric conversion layer that is opposite to the substrate by magnetron sputtering, chemical vapor deposition, atomic layer deposition (ALD) or coating. A second scribing is performed by employing a means of laser scribing, masking or exposure to light to form a plurality of second openwork portions of the hole transport layer, the perovskite photoelectric conversion layer and the electron transport layer in the hole transport layer, the perovskite photoelectric conversion layer and the electron transport layer. A metal electrode is formed on the surface of the electron transport layer opposite the substrate by means of magnetron sputtering, chemical vapor deposition, atomic layer deposition (ALD) or coating. A third scribing is performed by adopting means of laser scribing, masking or exposure to form a third openwork portion in the metal electrode, the hole transport layer, the perovskite photoelectric conversion layer and the electron transport layer.

[0062] Based on the above steps, the positive output terminal and the negative output terminal may be welded by conductive tape bonding, ultrasonic welding, laser welding or welding with a welding agent to form an external output electrode. Then, an adhesive film is formed on the surface of the metal electrode that is separated from the substrate by radiation, and a cover plate glass is provided on the side of the adhesive film that is separated from the substrate, and finally the whole is sent into a laminator or a pressure cooker for compression and packaging.

[0063] In some embodiments, the solar cell 5 includes a plurality of dead zones 7, the dead zones 7 being provided between two adjacent subcells 6 to realize an electrical connection between the two adjacent subcells 6, and along the first direction Y, there is a positive correlation between the change trend of the thickness of the first photoelectric conversion layer 521 of each subcell 6 and the change trend of the cross-sectional area perpendicular to the thickness direction X of each dead zone 7.

[0064] In the process of dividing the solar cell 5 to form a plurality of subcells 6, a plurality of dead zones 7 are formed. The dead zones 7 are provided between two adjacent subcells 6 to realize electrical connection between the two adjacent subcells 6. In the embodiment of the present application, based on the fact that the thickness of the first photoelectric conversion layer 521 has a change tendency, the size of the cross-sectional area perpendicular to the thickness direction X of the dead zones 7 can be adjusted to optimize the filling rate and photoelectric conversion efficiency of the solar cell 5.

[0065] There is a contact resistance between the first electrode layer 51 and the second electrode layer 53 located in the dead zone 7, and the photoelectric conversion layer 52 located in the dead zone 7 itself has a certain resistance, and the above-mentioned resistances constitute a series connection resistance. The larger the cross-sectional area perpendicular to the thickness direction X of the dead zone 7, the larger the area of ​​light loss, and the larger the dead zone 7, the larger the series connection resistance formed by itself, and the lower the photocurrent output by the subcell 6. The smaller the cross-sectional area perpendicular to the thickness direction X of the dead zone 7, the smaller the area of ​​light loss, and the smaller the series connection resistance formed by itself, the higher the photocurrent output by the subcell 6. By adjusting the size of the cross-sectional area perpendicular to the thickness direction X of the dead zone 7, the series connection resistance can be optimized, the photocurrent can be improved, and the photoelectric conversion efficiency of the solar cell 5 can be improved.

[0066] In the examples of the present application, the thickness change trend of the photoelectric conversion layer 52 in the first direction Y substantially coincides with the thickness change trend of the first photoelectric conversion layer 521 in the first direction Y, and the thickness change trend of the photoelectric conversion layer 52 in the first direction Y substantially coincides with the thickness change trend of the second photoelectric conversion layer 522 in the first direction Y.

[0067] In the embodiment of the present application, there is a positive correlation between the change tendency of the thickness of the first photoelectric conversion layer 521 of each subcell 6 and the change tendency of the cross-sectional area perpendicular to the thickness direction X of each dead zone 7. That is, by combining a relatively thick first photoelectric conversion layer 521 with a dead zone 7 having a relatively large cross-sectional area, and by combining a relatively thin first photoelectric conversion layer 521 with a dead zone 7 having a relatively small cross-sectional area, the uniformity of the conversion and output current between each subcell 6 can be further adjusted.

[0068] Regardless of the change tendency of the thickness of the first photoelectric conversion layer 521, the change tendency of the cross-sectional area perpendicular to the thickness direction X of each dead zone 7 is positively correlated with the change tendency of the thickness, thereby adjusting the uniformity of the photocurrent converted and output by each subcell 6. Specifically, the cross-sectional area perpendicular to the thickness direction X of the dead zone 7 can be adjusted by adjusting the length or width dimension of the dead zone 7.

[0069] As some examples, along the first direction Y, the thickness of each first photoelectric conversion layer 521 becomes gradually smaller, and the cross-sectional area perpendicular to the thickness direction X of each dead zone 7 becomes gradually smaller. Specifically, along the first direction Y, the dimension of each dead zone 7 along the first direction Y becomes gradually smaller.

[0070] As another example, the thickness of each first photoelectric conversion layer 521 gradually increases along the first direction Y, and the cross-sectional area perpendicular to the thickness direction X of each dead zone 7 gradually increases along the first direction Y. Specifically, the dimension of each dead zone 7 along the first direction Y gradually increases along the first direction Y.

[0071] As yet another example, along the first direction Y, the thickness of each first photoelectric conversion layer 521 gradually increases and then gradually decreases, and as the thickness gradually increases, the cross-sectional area perpendicular to the thickness direction X of each dead zone 7 gradually increases, specifically, along the first direction Y, the dimension of each dead zone 7 along the first direction Y gradually increases, and as the thickness gradually decreases, the cross-sectional area perpendicular to the thickness direction X of each dead zone 7 gradually decreases, specifically, along the first direction Y, the dimension of each dead zone 7 along the first direction Y gradually decreases.

[0072] As yet another example, along the first direction Y, the thickness of each first photoelectric conversion layer 521 gradually becomes smaller and then gradually becomes larger, and as the thickness gradually becomes smaller, the cross-sectional area perpendicular to the thickness direction X of each dead zone 7 gradually becomes smaller; specifically, along the first direction Y, the dimension of each dead zone 7 along the first direction Y gradually becomes smaller and as the thickness gradually becomes larger, the cross-sectional area perpendicular to the thickness direction X of each dead zone 7 gradually becomes larger, and along the first direction Y, the dimension of each dead zone 7 along the first direction Y gradually becomes larger.

[0073] 3 has a tendency that the thickness gradually increases and then gradually decreases along the first direction Y. Exemplarily, the multiple dead zones 7 include at least a first dead zone 7a and a second dead zone 7b, and the thickness of the photoelectric conversion layer 52 gradually decreases in the direction from the first dead zone 7a to the second dead zone 7b. Accordingly, by adjusting the width W1 of the first dead zone 7a to be larger than the width W2 of the second dead zone 7b, the cross-sectional area perpendicular to the thickness direction X of the dead zone 7 can be reduced, and the series connection resistance can be reduced.

[0074] The dead zone 7 includes the area located from the first openwork portion P1 to the third openwork portion P3. In the embodiment of the present application, the first electrode layer 51, the photoelectric conversion layer 52, and the second electrode layer 53 are partially located in the area of ​​the plurality of subcells 6, and another portion is located in the dead zone 7. The photoelectric conversion layer 52 is divided into two portions including a first photoelectric conversion layer 521 and a second photoelectric conversion layer 522, the first photoelectric conversion layer 521 is located in the area of ​​the subcells 6, and the second photoelectric conversion layer 522 is located in the dead zone 7.

[0075] FIG. 4 is an enlarged schematic diagram of the structure of the dead zone of the solar cell shown in FIG.

[0076] 3 and 4, in some embodiments, the second photoelectric conversion layer 522 located in the dead zone 7 includes a first main body portion 71 and a first connection portion 72, the first main body portion 71 is located on the surface of the first electrode layer 51, and the first connection portion 72 connects the first main body portion 71 and the first electrode layer 51. The second electrode layer 53 located in the dead zone 7 includes a first body portion 73 and a first extension portion 74, the first body portion 73 is located on a surface of the first main body portion 71 that is separated from the first electrode layer 51, and the first extension portion 74 connects the first body portion 73 and the first electrode layer 51 located in the dead zone 7. The dead zone 7 further includes a through portion 75, which is the above-mentioned third openwork portion P3, and the through portion 75 extends through the first body portion 73 to a surface of the first electrode layer 51 close to the second photoelectric conversion layer 522. The manufacturing process of such a structural form is simple and the cost is low.

[0077] In the embodiment of the present application, the purpose of adjusting the size of the cross-sectional area perpendicular to the thickness direction X of the dead zone 7 can be achieved by adjusting the size of the first connecting portion 72, the first extending portion 74 and the through portion 75 through adjusting the size of at least one of the first openwork portion P1, the second openwork portion P2 and the third openwork portion P3. Exemplarily, when it is necessary to adjust the cross-sectional area of ​​the dead zone 7 to be gradually smaller, the size in the first direction Y of at least one of the first openwork portion P1, the second openwork portion P2 and the third openwork portion P3 is adjusted to be gradually smaller, and accordingly the size in the first direction Y of at least one of the first connecting portion 72, the first extending portion 74 and the through portion 75 is gradually smaller. Alternatively, if the cross-sectional area of ​​the dead zone 7 needs to be adjusted to be gradually larger, the dimension in the first direction Y of at least one of the first openwork portion P1, the second openwork portion P2 and the third openwork portion P3 is adjusted to be gradually larger, and the dimension in the first direction Y of at least one of the first connection portion 72, the first extension portion 74 and the through portion 75 is correspondingly gradually larger. In the embodiment of the present application, the purpose of adjusting the size of the dead zone 7 is achieved by adjusting the dimension of each openwork portion during the scribing process, thereby improving the photoelectric conversion efficiency.

[0078] Although the present application has been described with reference to the preferred embodiments, various improvements can be made thereto without departing from the scope of the present application, and equivalents can be substituted for the components therein, and in particular, each technical feature mentioned in each embodiment can be combined in any manner unless there is a conflict in structure. The present application is not limited to the specific embodiments disclosed in the specification, but includes all technical solutions within the scope of the claims. [Explanation of symbols]

[0079] X thickness direction Y Primary Direction P1 First fretwork section P2 Second fretwork section P3 Third fretwork section 1 vehicle 2. Photovoltaic Module 3. Controller 4 Motor 5. Solar Cells 50 Substrates 51 First electrode layer 52 Photoelectric conversion layer 521 First photoelectric conversion layer 522 Second photoelectric conversion layer 53 Second electrode layer 6 Subcells 6a First subcell 6b Second subcell 7. The Dead Zone 7a First Dead Zone 7b The second dead zone 71 First main body 72 First Connection 73 First body part 74 First extension 75 Penetration

Claims

1. A solar cell including a plurality of subcells arranged in sequence along a first direction, each of the plurality of subcells including a first photoelectric conversion layer for photoelectric conversion, the first direction being perpendicular to a thickness direction of the subcells; A solar cell in which the change trend of the thickness of the first photoelectric conversion layer of each of the subcells along the first direction and the change trend of the cross-sectional area perpendicular to the thickness direction of each of the first photoelectric conversion layers are negatively correlated so as to increase the uniformity of the photocurrent output between each of the subcells.

2. The solar cell according to claim 1 , wherein there is a negative correlation between a change trend in thickness of each of the first photoelectric conversion layers along the first direction and a change trend in dimension of each of the first photoelectric conversion layers along the first direction.

3. The solar cell according to claim 1 , wherein along the first direction, the thickness of each of the first photoelectric conversion layers gradually decreases, and the cross-sectional area perpendicular to the thickness direction of each of the first photoelectric conversion layers gradually increases.

4. The solar cell according to claim 3 , wherein a dimension of each of the first photoelectric conversion layers along the first direction gradually increases so that a cross-sectional area perpendicular to the thickness direction of each of the first photoelectric conversion layers gradually increases.

5. The solar cell comprises: a plurality of dead zones provided between two adjacent subcells to realize an electrical connection between the two adjacent subcells; The solar cell according to any one of claims 1 to 4, wherein along the first direction, there is a positive correlation between the change trend of the thickness of the first photoelectric conversion layer of each of the subcells and the change trend of the cross-sectional area of ​​each of the dead zones perpendicular to the thickness direction.

6. The solar cell according to claim 5 , wherein a thickness of each of the first photoelectric conversion layers gradually decreases along the first direction, and a cross-sectional area perpendicular to the thickness direction of each of the dead zones gradually decreases.

7. 7. The solar cell of claim 6, wherein the dimension along the first direction of each of the dead zones gradually decreases such that the cross-sectional area perpendicular to the thickness direction of each of the dead zones gradually decreases along the first direction.

8. Each of the plurality of dead zones comprises: A first electrode layer; a second photoelectric conversion layer including a first main body portion located on a surface of the first electrode layer and a first connection portion connected to the first main body portion and connecting the main body portion and the first electrode layer; a second electrode layer including a first body portion located on a surface of the second photoelectric conversion layer away from the first electrode layer, and a first extension portion connecting the first body portion and the first electrode layer; a through portion that penetrates the first body portion and extends to a surface of the first electrode layer that is close to the second photoelectric conversion layer, The solar cell according to claim 7 , wherein a dimension in the first direction of at least one of the first connection portion, the first extension portion, and the through portion gradually decreases along the first direction.

9. The subcell comprises: An electron transport layer connected to the first photoelectric conversion layer and for transporting electrons; and / or 9. The solar cell according to claim 1, further comprising a hole transport layer connected to the first photoelectric conversion layer for transporting holes.

10. A photovoltaic module comprising the solar cell according to any one of claims 1 to 9.

11. 11. A power consuming device comprising the photovoltaic module of claim 10.

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