Solar cell and preparation method thereof

Abstract

The invention discloses a solar cell and a preparation method thereof, the solar cell comprises a substrate and a cell structure, the cell structure comprises a plurality of cell assemblies, the plurality of cell assemblies are arranged on one side of the substrate, the plurality of cell assemblies comprise a first cell assembly, a second cell assembly and a third cell assembly, the first battery assembly comprises a plurality of first battery units which are arranged in series, the second battery assembly comprises at least one second battery unit, and the third battery assembly comprises at least one third battery unit; the third battery assembly is arranged between the first battery assembly and the second battery assembly, and the first battery assembly and the second battery assembly are connected in parallel through the third battery assembly.

Description

Technical Field

[0001] This application belongs to the field of battery technology, and in particular relates to a solar cell and its preparation method. Background Technology

[0002] The development of semiconductor technology plays a crucial role in the advancement of the electronics industry. Perovskite, as a novel semiconductor, possesses numerous advantages, including long carrier diffusion lengths, high defect tolerance, tunable band gaps, and large absorption coefficients. Compared to traditional organic and inorganic semiconductors, perovskite preparation processes are simpler and less expensive, giving it a significant advantage in the semiconductor field. To date, the efficiency of perovskite solar cells has exceeded 26%, and the time-to-hour (T95) has surpassed 1,000 hours. Furthermore, it has been researched and applied in light-emitting diodes, detectors, and lasers. As an emerging semiconductor material, perovskite has demonstrated enormous potential.

[0003] However, the performance of current perovskite solar cells needs to be improved. Summary of the Invention

[0004] The purpose of this application is to provide a solar cell and a method for preparing the same, which can improve the performance of solar cells.

[0005] The first aspect of this application provides a solar cell, including a substrate and a cell structure. The cell structure includes multiple cell modules disposed on one side of the substrate. The multiple cell modules include a first cell module, a second cell module, and a third cell module. The first cell module includes multiple first cell units arranged in series. The second cell module includes at least one second cell unit. The third cell module includes at least one third cell unit. The third cell module is disposed between the first cell module and the second cell module. The first cell module and the second cell module are connected in parallel through the third cell module.

[0006] In some embodiments, the first battery cell, the second battery cell, and the third battery cell each include a first electrode, a functional layer, and a second electrode stacked along a direction away from the substrate. The second electrode of a first battery cell and the second electrode of a second battery cell are respectively electrically connected to the first electrode of the same third battery cell, so that the first battery assembly and the second battery assembly are connected in parallel through the first electrode of the third battery assembly. Preferably, the second battery assembly includes a plurality of second battery cells arranged in series; Preferably, the number of battery cells in the first battery assembly is equal to or different from the number of battery cells in the second battery assembly; Preferably, the material of the functional layer includes perovskite, cadmium telluride, copper indium gallium selenide, or organic photovoltaic materials; Preferably, a first opening is formed between the functional layer of the third battery cell and the functional layer of the adjacent first battery cell, and the second electrode of the first battery cell adjacent to the third battery cell extends to the first opening and is electrically connected to the corresponding first electrode. Preferably, a second opening is formed between the functional layer of the third battery cell and the functional layer of the adjacent second battery cell, and the second electrode of the second battery cell adjacent to the third battery cell extends to the second opening and is electrically connected to the corresponding first electrode.

[0007] In some embodiments, the solar cell further includes a busbar structure, which includes a first busbar, a second busbar, and a third busbar. The first busbar is electrically connected to a first battery module, the second busbar is electrically connected to a second battery cell, and the third busbar is electrically connected to a third battery module. The first and second busbars have the same polarity and the opposite polarity to the third busbar. Preferably, the first battery cell, the second battery cell, and the third battery cell each include a first electrode, a functional layer, and a second electrode stacked along a direction away from the substrate. The second electrode of one first battery cell and the second electrode of one second battery cell are respectively electrically connected to the first electrode of the same third battery cell, so that the first battery assembly and the second battery assembly are connected in parallel through the first electrode of the third battery assembly. Preferably, the first busbar is electrically connected to the first electrode of the first battery assembly, the second busbar is electrically connected to the first electrode of the second battery assembly, and the third busbar is electrically connected to the second electrode of the third battery assembly. Preferably, at least a portion of the first busbar and at least a portion of the second busbar are disposed in the same layer as the first electrode; Preferably, along a direction parallel to the plane where the substrate is located, the first busbar is disposed on one side of the first battery assembly, the first electrode of the first battery assembly is connected to the side of the first busbar near the first battery assembly, and the second busbar is disposed on one side of the second battery assembly, the first electrode of the second battery assembly is connected to the side of the second busbar near the second battery assembly. Preferably, along a direction parallel to the plane where the substrate is located, the first busbar is disposed on the side of the first battery assembly away from the second battery assembly, the second busbar is disposed on the side of the second battery assembly away from the first battery assembly, and the first busbar and the second busbar are respectively disposed on both sides of the battery structure. Preferably, a portion of the third busbar covers the side of the second electrode of the third battery cell that faces away from the substrate; Preferably, there are multiple first battery modules, multiple second battery modules and multiple third battery modules, with multiple first battery modules and multiple second battery modules arranged alternately, and a third battery module is provided between adjacent first battery modules and second battery modules and connected in parallel through the third battery module; Preferably, there are multiple third busbars, and the multiple third busbars are electrically connected to multiple third battery modules; among the multiple first battery modules and multiple second battery modules, one first battery module is located on one side edge of the battery structure and is electrically connected to the first busbar, and one second battery module is located on the opposite side edge of the battery structure and is electrically connected to the second busbar.

[0008] In some embodiments, the solar cell further includes an encapsulation structure that covers a portion of the cell structure and the busbar structure; Preferably, the encapsulation structure includes a first barrier layer, the first barrier layer includes a main body portion and an edge portion, the main body portion covers the side of the battery structure away from the substrate, the edge portion is disposed on at least two sides of the main body portion, and the edge portion covers at least a portion of the surface of the first busbar that is away from the substrate and at least a portion of the surface of the second busbar that is away from the substrate. Preferably, the main body covers the third busbar; Preferably, a portion of the first electrode closest to the first busbar in the first battery assembly extends out of the corresponding functional layer, and the edge covers a portion of the corresponding first electrode; Preferably, a portion of the first electrode closest to the second busbar in the second battery assembly extends out of the corresponding functional layer, and the edge covers a portion of the corresponding first electrode.

[0009] In some embodiments, the encapsulation structure further includes a second barrier layer disposed between the substrate and the battery assembly, the second barrier layer covering the side of the first busbar and the second busbar close to the substrate; Preferably, the material of the first barrier layer is the same as or different from that of the second barrier layer; Preferably, the first barrier layer and / or the second barrier layer comprise inorganic materials; Preferably, the first barrier layer and / or the second barrier layer comprises at least one of silicon nitride, silicon oxide, and aluminum oxide; Preferably, the substrate includes a first substrate, a third barrier layer and a second substrate stacked together, wherein the second barrier layer is disposed on the side of the second substrate opposite to the first substrate.

[0010] In some embodiments, the first barrier layer forms a first through hole along a direction parallel to the substrate. The first through hole is located on one side of the second electrode of the third battery cell, and a portion of the third busbar passes through the first through hole. Preferably, the encapsulation structure further includes an encapsulation layer covering the first barrier layer, the encapsulation layer forming a second through hole, the second through hole communicating with the first through hole, and a portion of the third busbar passing through the second through hole; Preferably, the encapsulation structure further includes a dispensing encapsulation part, which is located in the second through hole and is disposed around the third busbar, and the side of the dispensing encapsulation part near the first through hole is connected to the first barrier layer. Preferably, the material of the dispensing and encapsulation part includes at least one of silicone, nano-silica, and crosslinking agent.

[0011] In some embodiments, the encapsulation layer also covers a portion of the bus structure; Preferably, the encapsulation structure further includes a second barrier layer, which is disposed between the substrate and the battery assembly, and the encapsulation layer also covers a portion of the second barrier layer and is connected to the second barrier layer. Preferably, the material of the encapsulation layer includes at least one of polyolefin elastomer, ethylene-vinyl acetate copolymer, and epoxy resin; Preferably, the solar cell further includes a cover plate disposed on the side of the encapsulation layer away from the substrate, and the cover plate is connected to the encapsulation layer.

[0012] In some embodiments, the packaging structure further includes a fourth barrier layer, which is disposed on the side of the first barrier layer away from the substrate. Preferably, the packaging structure further includes a planarization layer disposed between the first barrier layer and the fourth barrier layer; Preferably, the fourth barrier layer covers the side surface of the planarization layer facing away from the substrate and the side surface of the planarization layer, and is connected to the first barrier layer on the side surface.

[0013] In some embodiments, at least one of the first busbar and the second busbar includes an electrode lead-out portion and a busbar, the electrode lead-out portion being electrically connected to the first electrode, the busbar being electrically connected to the electrode lead-out portion, and the edge portion of the first barrier layer covering at least a portion of the surface of the electrode lead-out portion on the side away from the substrate. Preferably, the busbar is disposed on the side of the electrode lead-out portion away from the substrate, and the edge portion covers a portion of the surface of the electrode lead-out portion away from the substrate. Preferably, the electrode lead-out portion comprises a metal oxide material; Preferably, the electrode lead-out portion includes at least one of fluorine-doped tin oxide, indium tin oxide, and indium zinc oxide; Preferably, the material of the electrode lead-out portion is the same as or different from the material of the first electrode; Preferably, the busbar includes a bus body and a conductive adhesive layer, with the bus body bonded to the side of the electrode lead-out portion away from the substrate via the conductive adhesive layer.

[0014] A second aspect of this application provides a method for preparing a solar cell, the method being used to prepare the solar cell described in any of the above-mentioned embodiments, the method comprising: A battery structure is formed on one side of a substrate. The battery structure includes multiple battery components, including a first battery component, a second battery component, and a third battery component. The first battery component includes multiple first battery cells arranged in series. The second battery component includes at least one second battery cell. The third battery component includes at least one third battery cell. Each of the first, second, and third battery cells includes a first electrode, a functional layer, and a second electrode stacked in a direction away from the substrate. The third battery component is disposed between the first and second battery components. The first and second battery components are connected in parallel through the third battery component. A busbar structure is formed on one side of the substrate. The busbar structure includes a first busbar, a second busbar, and a third busbar. At least a portion of the first busbar and at least a portion of the second busbar are disposed in the same layer as the first electrode. The first busbar is electrically connected to the first electrode of the first battery assembly. The second busbar is electrically connected to the first electrode of the second battery assembly. A portion of the third busbar covers the side of the second electrode of the third battery assembly facing away from the substrate and is electrically connected to the second electrode of the third battery assembly.

[0015] This application provides a solar cell and its fabrication method. The solar cell includes a substrate and a cell structure. The cell structure includes multiple cell modules disposed on one side of the substrate. The multiple cell modules include a first cell module, a second cell module, and a third cell module. The first cell module includes multiple first cell units arranged in series. The second cell module includes at least one second cell unit. The third cell module includes at least one third cell unit. The third cell module is disposed between the first and second cell modules, enabling the first and second cell modules to be connected in parallel. This eliminates the need for additional conductive components for parallel connection of the first and second cell modules, simplifying the structure of the solar cell and reducing assembly and maintenance difficulties. Furthermore, the third cell module can perform photoelectric conversion, which helps improve the photoelectric conversion efficiency of the solar cell, thereby enhancing its performance. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments of this application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 Top view of a solar cell provided for some embodiments of this application; Figure 2 for Figure 1A cross-sectional view at point AA; Figure 3 for Figure 1 A cross-sectional view of point BB; Figure 4 for Figure 1 Another cross-sectional view of BB; Figure 5 Perspective views of solar cells provided in some embodiments of this application from a top view perspective; Figure 6 for Figure 1 Another cross-sectional view of BB; Figure 7 This is a flowchart illustrating a method for fabricating a solar cell according to some embodiments of this application.

[0018] The attached icons are numbered as follows: Solar cell 100; substrate 10; first substrate 11; third barrier layer 12; second substrate 13; cell assembly 20; first cell assembly 21; first cell unit 211; second cell assembly 22; second cell unit 221; third cell assembly 23; third cell unit 231; first electrode 24; functional layer 25; second electrode 26; busbar structure 30; first busbar 31; second busbar 32; third busbar 33; electrode lead-out portion 34; busbar strip 35; encapsulation structure 40; first barrier layer 41; main body portion 411; edge portion 412; second barrier layer 42; encapsulation layer 43; dispensing encapsulation portion 44; fourth barrier layer 45; planarization layer 46; cover plate 50; first opening K1; second opening K2; first through hole K3; second through hole K4. Detailed Implementation

[0019] The embodiments of this application will be described in further detail below with reference to the accompanying drawings and examples. The detailed description of the following embodiments and the accompanying drawings are used to illustrate the principles of this application by way of example, but should not be used to limit the scope of this application, that is, this application is not limited to the described embodiments.

[0020] In the description of this application, it should be noted that, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," and "outer," etc., indicating orientation or positional relationships, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. Furthermore, the terms "first," "second," and "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. "Vertical" is not vertical in the strict sense, but within the allowable tolerance range. "Parallel" is not parallel in the strict sense, but within the allowable tolerance range.

[0021] In this application, the reference to "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described in this application can be combined with other embodiments.

[0022] The directional terms used in the following description refer to the directions shown in the figures and are not intended to limit the specific structure of this application. It should also be noted in the description of this application that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0023] In some solar cells, multiple cells can be connected in series and parallel to regulate the output voltage and current. Currently, parallel connection between cells is typically achieved using conductive components such as busbars. However, the inclusion of these components complicates the internal structure of the solar cell, hindering assembly and maintenance. Furthermore, they occupy space within the solar cell, impacting its photoelectric conversion efficiency.

[0024] Therefore, in order to solve at least part of the above problems, this application provides a solar cell and a method for its fabrication. The structure of the solar cell will be described below with reference to the accompanying drawings.

[0025] Please see Figure 1 and Figure 2 The first aspect of this application provides a solar cell 100, including a substrate 10 and a cell structure (not shown in the figure). The cell structure includes a plurality of cell modules 20, which are disposed on one side of the substrate 10. The plurality of cell modules 20 include a first cell module 21, a second cell module 22 and a third cell module 23. The first cell module 21 includes a plurality of first cell units 211 arranged in series. The second cell module 22 includes at least one second cell unit 221. The third cell module 23 includes at least one third cell unit 231. The third cell module 23 is disposed between the first cell module 21 and the second cell module 22. The first cell module 21 and the second cell module 22 are connected in parallel through the third cell module 23.

[0026] It should be noted that the solar cell 100 provided in this application can be any type of battery capable of photoelectric conversion. For example, the solar cell 100 in this application can be a perovskite battery, or a cadmium telluride battery (CdTe), a copper indium gallium selenide battery (CIGS), an organic photovoltaic cell (OPV), etc. This embodiment is not limited to any particular type.

[0027] The substrate 10 serves to support each battery module 20. It includes a substrate, which can be a rigid substrate made of materials such as glass or plastic, or a flexible substrate made of materials such as polyethersulfone (PES), polyacrylate (PAR), polyetherimide (PEI), polyethylene naphthalate (PEN), polyethylene terephthalate (PET), polyphenylene sulfide (PPS), polyarylate, polyimide (PI), polycarbonate (PC), cellulose acetate propionate (CAP), thin glass, or thin metal plate. When the substrate 10 includes a flexible substrate, the corresponding solar cell 100 can be a flexible cell; when the substrate 10 includes a rigid substrate, the corresponding solar cell 100 can be a rigid cell. Optionally, the substrate 10 can include a light-transmitting material, allowing external light to pass through the substrate 10 and be incident on the battery module 20. That is, the substrate 10 side of each battery cell can be the light-incident side, and the side of each battery cell facing away from the substrate 10 can be the backlight side.

[0028] In the battery structure, the number of battery components 20 can be flexibly set according to actual conditions, and this embodiment does not impose any limitation on this. Multiple battery components 20 include a first battery component 21, a second battery component 22, and a third battery component 23, wherein the first battery component 21 includes a first battery cell 211, the second battery component 22 includes a second battery cell 221, and the third battery component 23 includes a third battery cell 231. The first battery cell 211, the second battery cell 221, and the third battery cell 231 can all include a first electrode 24, a functional layer 25, and a second electrode 26 stacked along a direction away from the substrate 10.

[0029] Optionally, the functional layer 25 may include a photosensitive layer. The first electrode 24 may be a cathode, and the second electrode 26 may be an anode. When external wires pass through to the photosensitive layer, the photosensitive layer can function and generate electron-hole pairs. Under the action of the electric field formed by the first electrode 24 and the second electrode 26, electrons and holes can move toward the second electrode 26 and the first electrode 24 respectively, and form a current during the movement, thereby realizing photoelectric conversion.

[0030] Optionally, the functional layer 25 may include a first carrier transport layer, a photosensitive layer, and a second carrier transport layer stacked sequentially in a direction away from the substrate 10. The first carrier transport layer and the second carrier transport layer may be used to transfer electrons and holes, respectively, thereby improving the photoelectric conversion efficiency.

[0031] Optionally, the first electrode 24 may include a light-transmitting material. Optionally, the first electrode 24 may include materials such as indium tin oxide (ITO) or fluorinated tin oxide (FTO). Optionally, the second electrode 26 may include a light-transmitting material, such as indium tin oxide (ITO) or fluorinated tin oxide (FTO). Alternatively, the second electrode 26 may also include an opaque material, for example, copper or silver.

[0032] The first battery assembly 21 is provided with a plurality of first battery units 211, and each first battery unit 211 is connected in series. The second electrode 26 of one first battery unit 211 can be electrically connected to the first electrode 24 of another adjacent first battery unit 211, thereby realizing the series connection of two adjacent first battery units 211.

[0033] The second battery assembly 22 may have one or more second battery units 221. When the second battery assembly 22 has multiple second battery units 221, the multiple second battery units 221 may be connected in series or in parallel, or a portion of the multiple second battery units 221 may be connected in series and another portion may be connected in parallel.

[0034] The third battery assembly 23 may have one or more third battery units 231. When the third battery assembly 23 has multiple third battery units 231, the multiple third battery units 231 may be connected in series or in parallel, or a portion of the multiple third battery units 231 may be connected in series and another portion may be connected in parallel.

[0035] The third battery module 23 is located between the first battery module 21 and the second battery module 22. The first battery module 21 and the second battery module 22 are connected in parallel through the third battery module 23. Therefore, there is no need to set up additional conductive parts for connecting the first battery module 21 and the second battery module 22 in parallel. This simplifies the structure of the solar cell 100 and reduces the assembly and maintenance difficulty of the solar cell 100. At the same time, the third battery module 23 can also perform photoelectric conversion, which helps to improve the photoelectric conversion efficiency of the solar cell 100, thereby improving the performance of the solar cell 100.

[0036] It should be noted that the second electrodes 26 of the first battery assembly 21 and the second battery assembly 22 can be electrically connected to the first electrode 24 of the third battery assembly 23, thereby achieving a parallel connection. Alternatively, the first electrodes 24 of the first battery assembly 21 and the second battery assembly 22 can be electrically connected to the second electrode 26 of the third battery assembly 23, thereby achieving a parallel connection.

[0037] Please continue reading. Figure 2In some embodiments, the first battery unit 211, the second battery unit 221 and the third battery unit 231 each include a first electrode 24, a functional layer 25 and a second electrode 26 stacked along a direction away from the substrate 10. The second electrode 26 of one first battery unit 211 and the second electrode 26 of one second battery unit 221 are respectively electrically connected to the first electrode 24 of the same third battery unit 231, so that the first battery assembly 21 and the second battery assembly 22 are connected in parallel through the first electrode 24 of the third battery assembly 23.

[0038] Specifically, when there is one third battery unit 231 in the third battery assembly 23, the second electrode 26 of the first battery unit 211 and the second electrode 26 of the second battery unit 221 are simultaneously electrically connected to the first electrode 24 of the third battery unit 231. When there are multiple third battery units 231 in the third battery assembly 23, the multiple third battery units 231 can be connected in series, and the second electrode 26 of the first battery unit 211 and the second electrode 26 of the second battery unit 221 can be simultaneously electrically connected to the first electrode 24 of the same third battery unit 231.

[0039] In this embodiment, when the second electrode 26 of a first battery unit 211 and the second electrode 26 of a second battery unit 221 are respectively electrically connected to the first electrode 24 of the same third battery unit 231, the corresponding first battery assembly 21 and the corresponding second battery assembly 22 are connected in parallel. At the same time, the parallel structure formed by the first battery assembly 21 and the second battery assembly 22 can be connected in series with the corresponding third battery unit 231. Thus, by reasonably setting the number of battery units in each battery assembly 20, the series and parallel relationship of each battery unit can be flexibly adjusted, thereby controlling the output voltage and output current of the solar cell 100 according to actual needs, which helps to improve the application range of the solar cell 100.

[0040] Please continue reading. Figure 2 Preferably, the second battery assembly 22 includes a plurality of second battery cells 221 arranged in series to flexibly adjust the output voltage and output current of the solar cell 100.

[0041] In some alternative embodiments, the number of battery cells in the first battery module 21 is equal to the number of battery cells in the second battery module 22, so as to reduce the difficulty of regulating the output voltage and output current of the solar cell 100 and the difficulty of manufacturing the solar cell 100.

[0042] In some alternative embodiments, the number of battery cells in the first battery module 21 is different from the number of battery cells in the second battery module 22, so as to improve the flexibility of the output voltage and output current regulation of the solar cell 100 and expand the application range of the solar cell 100.

[0043] Preferably, the material of the functional layer 25 includes perovskite, cadmium telluride, copper indium gallium selenide, or organic photovoltaic materials. That is, the photosensitive layer may include perovskite material, cadmium telluride material, copper indium gallium selenide material, or organic photovoltaic material. The solar cell in this application embodiment may be a perovskite cell, cadmium telluride cell (CdTe), copper indium gallium selenide cell (CIGS), or organic photovoltaic cell (OPV).

[0044] Preferably, the material of the functional layer 25 includes perovskite. Perovskite materials have advantages such as high efficiency and low cost. Using perovskite materials to prepare the photosensitive layer helps to improve the photoelectric conversion efficiency of the solar cell 100 and reduce the production cost of the solar cell 100. At the same time, perovskite materials also have good flexibility, which facilitates the formation of a stable and reliable flexible solar cell 100.

[0045] Please continue reading. Figure 2 Preferably, a first opening K1 is formed between the functional layer 25 of the third battery unit 231 and the functional layer 25 of the adjacent first battery unit 211, and the second electrode 26 of the first battery unit 211 adjacent to the third battery unit 231 extends to the first opening K1 and is electrically connected to the corresponding first electrode 24.

[0046] The first electrode 24 of the third battery cell 231 can be exposed at the end of the first opening K1 near the substrate 10. The second electrode 26 of the first battery cell 211 adjacent to the third battery cell 231 can extend into the corresponding first opening K1 to overlap with the first electrode 24 exposed through the first opening K1.

[0047] In the fabrication process of solar cell 100, a plurality of first electrodes 24 spaced apart can be formed on one side of substrate 10. Then, a functional material layer is formed on the side of the first electrode 24 away from substrate 10. The material of the functional layer 25 can be grooved by etching and other processes to form a first opening K1. In the subsequent fabrication process of second electrode 26, the material of second electrode 26 falls into the first opening K1 and can overlap with the first electrode 24 exposed in the first opening K1, which helps to reduce the fabrication difficulty of solar cell 100.

[0048] Please continue reading. Figure 2 Preferably, a second opening K2 is formed between the functional layer 25 of the third battery unit 231 and the functional layer 25 of the adjacent second battery unit 221, and the second electrode 26 of the second battery unit 221 adjacent to the third battery unit 231 extends to the second opening K2 and is electrically connected to the corresponding first electrode 24.

[0049] The first electrode 24 of the third battery cell 231 can be exposed at one end of the second opening K2 near the substrate 10. The second electrode 26 of the second battery cell 221 adjacent to the third battery cell 231 can extend into the corresponding second opening K2 to overlap with the first electrode 24 exposed through the second opening K2.

[0050] In the fabrication process of solar cell 100, a plurality of first electrodes 24 spaced apart can be formed on one side of substrate 10. Then, a functional material layer is formed on the side of the first electrode 24 away from substrate 10. The material of the functional layer 25 can be grooved by etching and other processes to form a second opening K2. In the subsequent fabrication process of second electrode 26, the material of second electrode 26 falls into the second opening K2 and can overlap with the first electrode 24 exposed in the second opening K2, which helps to reduce the fabrication difficulty of solar cell 100.

[0051] Optionally, the first opening K1 and the second opening K2 can be formed in the same process to simplify the fabrication process of the solar cell 100.

[0052] Optionally, a third opening may be provided between the functional layers 25 of any two adjacent first battery cells 211, and the second electrode 26 of one of the two adjacent first battery cells 211 may be connected to the first electrode 24 of the other through the third opening, thereby realizing the series connection of the two adjacent first battery cells 211.

[0053] Optionally, a fourth opening may be provided between the functional layers 25 of any two adjacent second battery cells 221, and the second electrode 26 of one of the two adjacent second battery cells 221 may be connected to the first electrode 24 of the other through the fourth opening, thereby realizing the series connection of the two adjacent second battery cells 221.

[0054] Please see Figure 3 In some embodiments, the solar cell 100 further includes a busbar structure 30, which includes a first busbar 31, a second busbar 32, and a third busbar 33. The first busbar 31 is electrically connected to the first battery assembly 21, the second busbar 32 is electrically connected to the second battery cell 221, and the third busbar 33 is electrically connected to the third battery assembly 23. The first busbar 31 and the second busbar 32 have the same polarity and the third busbar 33 has the opposite polarity, so as to realize the electrode lead-out of each battery assembly 20 by using the first busbar 31, the second busbar 32, and the third busbar 33.

[0055] The first bus 31 and the second bus 32 have the same polarity, and both the first bus 31 and the second bus 32 have the opposite polarity to the third bus 33.

[0056] Optionally, when the second electrode 26 of a first battery unit 211 and the second electrode 26 of a second battery unit 221 are electrically connected to the first electrode 24 of the same third battery unit 231 to achieve parallel connection of the first battery assembly 21 and the second battery assembly 22, the first busbar 31 and the second busbar 32 can be electrically connected to the first electrode 24 of the first battery assembly 21 and the second battery assembly 22, respectively, and the third busbar 33 can be electrically connected to the second electrode 26 of the corresponding third battery unit 231 to achieve electrode lead-out. Alternatively, when the first electrode 24 of a first battery unit 211 and the first electrode 24 of a second battery unit 221 are electrically connected to the second electrode 26 of the same third battery unit 231 to achieve parallel connection of the first battery assembly 21 and the second battery assembly 22, the first busbar 31 and the second busbar 32 can be electrically connected to the second electrode 26 of the first battery assembly 21 and the second battery assembly 22, respectively, and the third busbar 33 can be electrically connected to the first electrode 24 of the corresponding third battery unit 231 to achieve electrode lead-out.

[0057] Preferably, the first battery unit 211, the second battery unit 221 and the third battery unit 231 each include a first electrode 24, a functional layer 25 and a second electrode 26 stacked in a direction away from the substrate 10. The second electrode 26 of one first battery unit 211 and the second electrode 26 of one second battery unit 221 are respectively electrically connected to the first electrode 24 of the same third battery unit 231, so that the first battery assembly 21 and the second battery assembly 22 are connected in parallel through the first electrode 24 of the third battery assembly 23.

[0058] Preferably, the first busbar 31 is electrically connected to the first electrode 24 of the first battery assembly 21, the second busbar 32 is electrically connected to the first electrode 24 of the second battery assembly 22, and the third busbar 33 is electrically connected to the second electrode 26 of the third battery assembly 23.

[0059] Specifically, when the first electrode 24 of the third battery assembly 23 is connected in parallel with the first battery assembly 21 and the second battery assembly 22, the second electrode 26 of a first battery unit 211 and the second electrode 26 of a second battery unit 221 are respectively electrically connected to the first electrode 24 of the same third battery unit 231. At this time, the second electrode 26 of the third battery unit 231 is an independent electrode. Therefore, the electrode of the independent second electrode 26 is led out through the third busbar 33. At the same time, the first busbar 31 and the second busbar 32 are used to lead out the first electrode 24 of each first battery unit 211 and the second battery unit 221, so as to realize the input and output of the solar cell 100.

[0060] Preferably, at least a portion of the first busbar 31 and at least a portion of the second busbar 32 are disposed in the same layer as the first electrode 24.

[0061] In each battery module 20, the first electrode 24 is disposed between the functional layer 25 and the substrate 10. At least a portion of the first busbar 31 and at least a portion of the second busbar 32 can be directly disposed on one side of the substrate 10, so as to be disposed in the same layer as each first electrode 24. The overlapping difficulty of the busbars and the first electrodes 24 disposed in the same layer is low, which helps to reduce the fabrication difficulty of the solar cell 100 and improve the production efficiency of the solar cell 100.

[0062] Preferably, along a direction parallel to the plane where the substrate 10 is located, the first busbar 31 is disposed on one side of the first battery assembly 21, the first electrode 24 of the first battery assembly 21 is connected to the side of the first busbar 31 near the first battery assembly 21, and the second busbar 32 is disposed on one side of the second battery assembly 22, the first electrode 24 of the second battery assembly 22 is connected to the side of the second busbar 32 near the second battery assembly 22.

[0063] The first busbar 31 can be disposed on any side of the first battery assembly 21. For example, the first busbar 31 can be located on the side of the first battery assembly 21 away from the second battery assembly 22, or the first busbar 31 can be located on another side adjacent to the side of the first battery assembly 21 away from the second battery assembly 22.

[0064] The second busbar 32 can be disposed on any side of the second battery assembly 22. For example, the second busbar 32 can be located on the side of the second battery assembly 22 away from the first battery assembly 21, or the second busbar 32 can be located on another side adjacent to the side of the second battery assembly 22 away from the first battery assembly 21.

[0065] In this embodiment, in a direction parallel to the plane of the substrate 10, the first electrode 24 of the first battery assembly 21 can overlap with the side of the first busbar 31 near the first battery assembly 21, and the first electrode 24 of the second battery assembly 22 can overlap with the side of the second busbar 32 near the second battery assembly 22. This further reduces the difficulty of overlapping the busbar with the corresponding first electrode 24, and lowers the fabrication difficulty of the solar cell 100. Simultaneously, having the first electrode 24 overlap the side of the corresponding busbar avoids it occupying space on the surface of the corresponding busbar away from the substrate 10, which helps to increase the contact area between the subsequently fabricated encapsulation structure 40 and the first and second busbars 31, improving encapsulation reliability and stability.

[0066] Preferably, along a direction parallel to the plane containing the substrate 10, the first busbar 31 is disposed on the side of the first battery assembly 21 away from the second battery assembly 22, and the second busbar 32 is disposed on the side of the second battery assembly 22 away from the first battery assembly 21. The first busbar 31 and the second busbar 32 can be disposed on opposite sides of the battery structure to reasonably arrange the positions of the first busbar 31 and the second busbar 32 and reduce interference between the first busbar 31 and the second busbar 32 and other structures.

[0067] Preferably, a portion of the third busbar 33 covers the side of the second electrode 26 of the third battery cell 231 away from the substrate 10, so as to electrically connect the second electrode 26 of the third battery cell 231 away from the substrate 10. This helps to reduce the difficulty of connecting the third busbar 33 and the corresponding second electrode 26, and reduce the difficulty of fabricating the solar cell 100.

[0068] Furthermore, in this embodiment, when the second electrode 26 of a first battery cell 211 and the second electrode 26 of a second battery cell 221 are respectively electrically connected to the first electrode 24 of the same third battery cell 231 to realize the parallel connection of the first battery assembly 21 and the second battery assembly 22, the second electrode 26 of the third battery cell 231 is an independent electrode. Therefore, by providing a third busbar 33 on the side of the independent second electrode 26 away from the substrate 10, the electrode can be led out using the third busbar 33. At the same time, the third busbar 33 is located on the backlight side of the corresponding third battery cell 231, thereby avoiding the influence of the setting of the third busbar 33 on the transmission of external light and helping to improve the photoelectric conversion efficiency of the third battery cell 231.

[0069] It should be noted that when the first electrode 24 of a first battery cell 211 and the first electrode 24 of a second battery cell 221 are electrically connected to the second electrode 26 of the same third battery cell 231, thereby realizing the parallel connection of the first battery assembly 21 and the second battery assembly 22, the first electrode 24 of the third battery cell 231 is an independent electrode. The third busbar 33 can be electrically connected to this independent first electrode 24 to realize electrode lead-out. At the same time, in order to avoid the arrangement of the third busbar 33 affecting the performance of the functional layer 25 and the second electrode 26 on the side of the first electrode 24 of the third battery cell 231 facing away from the substrate 10, the third busbar 33 can be arranged on the side of the independent first electrode 24 facing the substrate 10, that is, the light-incident side.

[0070] Optionally, the third busbar 33 may be formed using a printed silver paste process.

[0071] Optionally, the thickness of the third busbar 33 can be 1um to 10um. For example, the thickness of the third busbar 33 can be 1um, 3um, 4um, 5um, 7um, 8um, 10um or any other value between the two aforementioned values, so as to reasonably set the thickness of the third busbar 33 and improve the conductivity of the third busbar 33.

[0072] Optionally, the width of the third busbar 33 can be 1mm to 7mm. For example, the width of the third busbar 33 can be 1mm, 2mm, 2.5mm, 3mm, 5mm, 6mm, 7mm or any other value between the two aforementioned values, so as to reasonably set the width of the third busbar 33 and improve the conductivity of the third busbar 33.

[0073] Preferably, there are multiple first battery components 21, multiple second battery components 22 and multiple third battery components 23, with multiple first battery components 21 and multiple second battery components 22 arranged alternately, and a third battery component 23 is provided between adjacent first battery components 21 and second battery components 22 and connected in parallel through the third battery component 23.

[0074] In the plurality of first battery modules 21 and the plurality of second battery modules 22, a second battery module 22 may be provided between two adjacent first battery modules 21, and a first battery module 21 may be provided between two adjacent second battery modules 22. A third battery module 23 may be provided between adjacent first battery modules 21 and second battery modules 22. The adjacent first battery modules 21 and second battery modules 22 can be connected in parallel through the third battery module 23 between them, thereby realizing flexible adjustment of the current and voltage of the solar cell 100.

[0075] Preferably, there are multiple third busbars 33, and the multiple third busbars 33 are electrically connected to multiple third battery components 23; among the multiple first battery components 21 and multiple second battery components 22, one first battery component 21 is located on one side edge of the battery structure and is electrically connected to the first busbar 31, and one second battery component 22 is located on the opposite side edge of the battery structure and is electrically connected to the second busbar 32.

[0076] Specifically, in the busbar structure 30, the number of first busbars 31 and second busbars 32 can both be one, and the number of third busbars 33 can correspond to the number of third battery components 23. Multiple third busbars 33 can be electrically connected one-to-one with multiple third battery components 23. The battery structure may include a first edge and a second edge disposed opposite to each other, wherein a first battery component 21 is located at the first edge and is electrically connected to the first busbar 31. A second battery component 22 is located at the second edge and is electrically connected to the second busbar 32.

[0077] Please continue reading. Figure 3 In some embodiments, the solar cell 100 further includes an encapsulation structure 40 that covers a portion of the battery structure and the busbar structure 30 to encapsulate the battery assembly 20 and a portion of the busbar structure 30, thereby improving the sealing performance of the solar cell 100.

[0078] Specifically, the encapsulation structure 40 can comprehensively cover the battery structure from the side surface facing the substrate 10, the side surface away from the substrate 10, and the peripheral side surface of the battery structure to improve the encapsulation reliability of the battery structure. Furthermore, the encapsulation structure 40 can cover a portion of the busbar structure 30. Specifically, the encapsulation structure 40 can simultaneously cover a portion of the first busbar 31, a portion of the second busbar 32, and a portion of the third busbar 33. Other portions of the first busbar 31, the second busbar 32, and the third busbar 33 can all protrude through the encapsulation structure 40. While enabling the electrode lead-out of the battery structure, the encapsulation structure 40 can encapsulate the busbar structure 30 to prevent impurities such as water and oxygen from spreading to the battery structure through the busbar structure 30 and affecting the battery structure's performance.

[0079] Preferably, the encapsulation structure 40 includes a first barrier layer 41, which includes a main body portion 411 and an edge portion 412. The main body portion 411 covers the side of the battery structure away from the substrate 10, and the edge portion 412 is disposed on at least two sides of the main body portion 411. The edge portion 412 covers at least a portion of the surface of the first busbar 31 away from the substrate 10 and at least a portion of the surface of the second busbar 32 away from the substrate 10.

[0080] The first barrier layer 41 may comprise a dense organic or inorganic material. The first barrier layer 41 includes a main body 411 and an edge portion 412. The main body 411 covers the side of the battery structure facing away from the substrate 10, thus protecting the battery structure from this side. The edge portion 412 may be disposed on at least two sides of the main body 411, thus encapsulating the battery structure from these at least two sides. Furthermore, the edge portion 412 also covers at least a portion of the surface of the first busbar 31 facing away from the substrate 10 and at least a portion of the surface of the second busbar 32 facing away from the substrate 10, thereby encapsulating the first busbar 31 and the second busbar 32 on the side facing away from the substrate 10, reducing the risk of impurities such as water and oxygen spreading to the battery structure via the first busbar 31 and the second busbar 32.

[0081] It is understood that, since at least a portion of the first busbar 31 and at least a portion of the second busbar 32 are disposed on the same layer as the first electrode 24, and the first electrode 24 of the first battery assembly 21 can overlap with the side of the first busbar 31 near the first battery assembly 21, and the first electrode 24 of the second battery assembly 22 can overlap with the side of the second busbar 32 near the second battery assembly 22, therefore, the first electrode 24 of the first battery assembly 21 does not need to occupy the space on the side of the first busbar 31 away from the substrate 10, and the first electrode 24 of the second battery assembly 22... The electrode 24 does not need to occupy the space on the side of the second busbar 32 away from the substrate 10, so that the side of the first busbar 31 away from the substrate 10 and the side of the second busbar 32 away from the substrate 10 have sufficient space to contact the edge portion 412 of the first barrier layer 41. This helps to increase the contact area between the edge portion 412 and the surface of the first busbar 31 away from the substrate 10 and the surface of the second busbar 32 away from the substrate 10, thereby improving the encapsulation effect of the first barrier layer 41 on the battery structure, the first busbar 31 and the second busbar 32.

[0082] Preferably, the main body 411 covers the third busbar 33 to encapsulate the third busbar 33. A portion of the main body 411 covers the surface of the third busbar 33 away from the substrate 10, and another portion covers the surface of the battery structure away from the substrate 10.

[0083] Preferably, a portion of the first electrode 24 closest to the first busbar 31 in the first battery assembly 21 extends out of the corresponding functional layer 25, and the edge portion 412 covers a portion of the corresponding first electrode 24. This extension of the first electrode 24 closest to the first busbar 31 into the corresponding functional layer 25 facilitates the connection between the first electrode 24 and the first busbar 31. The edge portion 412 can simultaneously cover at least a portion of the first busbar 31 and the aforementioned extended portion of the first electrode 24, thereby encapsulating the first busbar 31 and the battery structure.

[0084] For example, the first busbar 31 is disposed on the side of the first battery assembly 21 away from the second battery assembly 22. In the first battery assembly 21, the first electrode 24, which is furthest from the second battery assembly 22, can extend a corresponding functional layer 25 in the direction away from the second battery assembly 22 and overlap the side of the first busbar 31 near the first battery assembly 21.

[0085] Preferably, a portion of the first electrode 24 closest to the second busbar 32 in the second battery assembly 22 extends out of the corresponding functional layer 25, and the edge portion 412 covers a portion of the corresponding first electrode 24. This extension of the first electrode 24 closest to the second busbar 32 into the corresponding functional layer 25 facilitates the connection between the first electrode 24 and the second busbar 32. The edge portion 412 can simultaneously cover at least a portion of the second busbar 32 and the aforementioned extended portion of the first electrode 24, thereby encapsulating the second busbar 32 and the battery structure.

[0086] For example, the second busbar 32 is disposed on the side of the second battery assembly 22 away from the first battery assembly 21. In the second battery assembly 22, the first electrode 24, which is furthest from the first battery assembly 21, can extend a corresponding functional layer 25 in a direction away from the first battery assembly 21 and overlap the side of the second busbar 32 near the second battery assembly 22.

[0087] Please continue reading. Figure 3 In some embodiments, the encapsulation structure 40 further includes a second barrier layer 42 disposed between the substrate 10 and the battery assembly 20, and the second barrier layer 42 covers the side of the first busbar 31 and the second busbar 32 near the substrate 10.

[0088] In the thickness direction of the substrate 10, the first barrier layer 41 and the second barrier layer 42 cover the battery structure and the busbar structure 30 from both sides, respectively, to encapsulate the battery structure and a portion of the busbar structure 30.

[0089] It should be noted that the first barrier layer 41 and the second barrier layer 42 can contact and connect with each other in the edge region of the substrate 10. The overall structure formed by the two can also cover a part of the battery structure and the busbar structure 30 from the side, thereby achieving the encapsulation of the battery structure and a part of the busbar structure 30. Alternatively, the first barrier layer 41 and the second barrier layer 42 can also be arranged at intervals and not in contact with each other. In this case, the encapsulation structure 40 can also include an encapsulation layer 43, which covers a part of the battery structure and the busbar structure 30 from the side, thereby achieving the encapsulation of the battery structure and a part of the busbar structure 30.

[0090] Preferably, the material of the first barrier layer 41 is the same as or different from that of the second barrier layer 42, so that the materials of the first barrier layer 41 and the second barrier layer 42 can be flexibly selected according to the actual situation.

[0091] Preferably, the first barrier layer 41 and / or the second barrier layer 42 comprise inorganic materials. Inorganic materials possess excellent water and oxygen barrier capabilities, superior stability and strength, and can form a dense encapsulation film, which helps improve the encapsulation effect and service life.

[0092] Preferably, the first barrier layer 41 and / or the second barrier layer 42 comprise at least one of silicon nitride, silicon oxide, and aluminum oxide. Inorganic materials such as silicon nitride, silicon oxide, and aluminum oxide have excellent water and oxygen barrier capabilities, which helps to form a dense encapsulation film.

[0093] Optionally, the first barrier layer 41 and / or the second barrier layer 42 may be prepared using chemical vapor deposition, plasma-enhanced chemical vapor deposition, atomic deposition, or other similar processes.

[0094] Please see Figure 4 Preferably, the substrate 10 includes a first substrate 11, a third barrier layer 12 and a second substrate 13 stacked together, with the second barrier layer 42 disposed on the side of the second substrate 13 opposite to the first substrate 11.

[0095] In this embodiment, by providing a third barrier layer 12 in the substrate 10, the third barrier layer 12 can cooperate with the first barrier layer 41 and the second barrier layer 42 to encapsulate the battery structure and the busbar structure 30, which helps to further improve the sealing performance of the solar cell 100.

[0096] Please see Figure 5 In some embodiments, the first barrier layer 41 forms a first through-hole K3. Along a direction parallel to the substrate 10, the first through-hole K3 is located on one side of the second electrode 26 of the third battery cell 231, and a portion of the third busbar 33 passes through the first through-hole K3. A portion of the third busbar 33 can extend out of the first barrier layer 41 through the first through-hole K3, thereby enabling electrode lead-out. Furthermore, the portion of the first barrier layer 41 forming the first through-hole K3 can circumferentially support and seal the third busbar 33, thereby improving the stability of the third busbar 33 and reducing the risk of impurities such as water and oxygen spreading to the battery structure via the third busbar 33.

[0097] It should be noted that, along the extending direction of the third busbar 33, at least one side of the third battery cell 231 is provided with an edge portion 412 of the first barrier layer 41, which can define the first through hole K3.

[0098] Optionally, the extension direction of the third busbar 33 can be parallel to the plane of the substrate 10. That is, the third busbar 33 can extend along a direction parallel to the plane of the substrate 10 on the side of the second electrode 26 of the third battery cell 231 that is away from the substrate 10, without bending along the thickness direction of the substrate 10. Correspondingly, the extension direction of the first through hole K3 can be parallel to the plane of the substrate 10. That is, the first through hole K3 extends along a direction parallel to the substrate 10, without bending along the thickness direction of the substrate 10.

[0099] like Figures 3-5As shown, preferably, the encapsulation structure 40 includes an encapsulation layer 43 covering the first barrier layer 41. The encapsulation layer 43 forms a second through hole K4, which communicates with the first through hole K3. A portion of the third busbar 33 passes through the second through hole K4, so that the encapsulation layer 43 can also support and seal the third busbar 33 circumferentially, thereby further improving the stability of the third busbar 33 and further reducing the risk of impurities such as water and oxygen spreading to the battery structure through the third busbar 33.

[0100] The encapsulation layer 43 covers the side of the first barrier layer 41 away from the substrate 10 and the side of the first barrier layer 41. The portion of the encapsulation layer 43 covering the side of the first barrier layer 41 can form a second through hole K4.

[0101] In some alternative embodiments, the encapsulation structure 40 includes an encapsulation layer 43, which may be located on the side of the first barrier layer 41 away from the substrate 10, without covering the side of the first barrier layer 41.

[0102] like Figure 5 As shown, preferably, the encapsulation structure 40 further includes a dispensing encapsulation part 44, which is located inside the second through hole K4 and is disposed around the third busbar 33. The side of the dispensing encapsulation part 44 near the first through hole K3 is connected to the first barrier layer 41.

[0103] In the extending direction of the third busbar 33, the third busbar 33 first passes through the first barrier layer 41 through the first through hole K3, and then passes through the encapsulation layer 43 through the second through hole K4. At the connection between the first through hole K3 and the second through hole K4, the encapsulation layer 43 may not be able to completely cover the third busbar 33, and there may be a small gap between the third busbar 33 and the inner wall of the second through hole K4.

[0104] Therefore, in this embodiment, by providing a dispensing and encapsulation part 44 inside the second through hole K4, the dispensing and encapsulation part 44 surrounds the third busbar 33, and the side of the dispensing and encapsulation part 44 near the first through hole K3 is connected to the first barrier layer 41. Thus, the dispensing and encapsulation part 44 can effectively fill the gap between the third busbar 33 at the connection between the first through hole K3 and the second through hole K4 and the inner wall of the second through hole K4. The dispensing and encapsulation part 44 is equivalent to being able to encapsulate the first through hole K3 from the end face of the first through hole K3. Through the first barrier layer 41, the dispensing and encapsulation part 44, and the encapsulation layer 43, the third busbar 33 can achieve triple sealing and support, so as to effectively improve the encapsulation effect and stability of the third busbar 33.

[0105] The dispensing encapsulation part 44 is located inside the second through hole K4. The encapsulation layer 43 can cover the peripheral side of the dispensing encapsulation part 44 away from the third busbar 33 and the end face of the dispensing encapsulation part 44 away from the first barrier layer 41. Therefore, the encapsulation part can also support and seal the dispensing encapsulation part 44 to further improve the stability and sealing of the third busbar 33.

[0106] Preferably, the material of the dispensing and encapsulation part 44 includes at least one of organosilicon, nano-silica, and crosslinking agent to improve the contact performance between the dispensing and encapsulation part 44 and the third busbar 33, thereby improving its encapsulation effect on the third busbar 33.

[0107] In some embodiments, the encapsulation layer 43 also covers a portion of the bus structure 30 to further seal the bus structure 30 using the encapsulation layer 43.

[0108] It is understood that, in addition to forming a portion of the second through-hole K4 for accommodating the third busbar 33, the encapsulation layer 43 can also cover the first busbar 31 and the second busbar 32 to seal the first busbar 31 and the second busbar 32.

[0109] Preferably, the encapsulation structure 40 further includes a second barrier layer 42 disposed between the substrate 10 and the battery assembly 20. The encapsulation layer 43 also covers a portion of the second barrier layer 42 and is connected to the second barrier layer 42. The first barrier layer 41, the second barrier layer 42, and the encapsulation layer 43 can jointly encapsulate the busbar structure 30 and the battery structure to improve the encapsulation effect.

[0110] Preferably, the material of the encapsulation layer 43 includes at least one of polyolefin elastomer, ethylene-vinyl acetate copolymer and epoxy resin, which helps to improve the encapsulation effect of the encapsulation layer 43 and the bonding ability between the encapsulation layer 43 and the second barrier layer 42.

[0111] like Figure 3 and Figure 4 As shown, preferably, the solar cell 100 further includes a cover plate 50, which is disposed on the side of the encapsulation layer 43 away from the substrate 10. The cover plate 50 is connected to the encapsulation layer 43 and is used to provide protection for the encapsulation structure 40, the busbar structure 30, and the battery structure.

[0112] The cover plate 50 can be a flexible cover plate 50 or a rigid cover plate 50. Optionally, the cover plate 50 may include a light-transmitting material. Alternatively, the cover plate 50 may also include a light-blocking material; this embodiment does not limit this.

[0113] Please see Figure 6In some embodiments, the encapsulation structure 40 further includes a fourth barrier layer 45, which is disposed on the side of the first barrier layer 41 away from the substrate 10, to further encapsulate the battery structure and the busbar structure 30.

[0114] Preferably, the encapsulation structure 40 further includes a planarization layer 46, which is disposed between the first barrier layer 41 and the fourth barrier layer 45.

[0115] It is known that the battery structure is provided with a first opening K1, a second opening K2, a third opening, a fourth opening and other spacer grooves. The main body 411 of the first barrier layer 41 covers the side of the battery structure away from the substrate 10. The side of the first barrier layer 41 away from the substrate 10 can form a recess corresponding to the aforementioned openings and spacer grooves.

[0116] Therefore, in this embodiment, a planarization layer 46 is provided on the side of the first barrier layer 41 facing away from the substrate 10. The planarization layer 46 fills the depression on the side of the first barrier layer 41 facing away from the substrate 10, so that the fourth barrier layer 45 is formed on a relatively flat surface. This helps to improve the continuity of the fourth barrier layer 45 and enhance its sealing performance. At the same time, the planarization layer 46 can also cover the impurity particles on the side of the first barrier layer 41 facing away from the substrate 10, preventing these impurity particles from affecting the bonding between the first barrier layer 41 and the fourth barrier layer 45, thereby reducing the risk of the fourth barrier layer 45 separating or falling off from the first barrier layer 41.

[0117] Optionally, the planarization layer 46 may include an epoxy resin.

[0118] Preferably, the fourth barrier layer 45 covers the side surface of the planarization layer 46 away from the substrate 10 and the side surface of the planarization layer 46, and is connected to the first barrier layer 41 on the side surface to improve the stability of the fourth barrier layer 45.

[0119] Please see Figures 3-6 In some embodiments, at least one of the first busbar 31 and the second busbar 32 includes an electrode lead-out portion 34 and a busbar 35. The electrode lead-out portion 34 is electrically connected to the first electrode 24, and the busbar 35 is electrically connected to the electrode lead-out portion 34. The edge portion 412 of the first barrier layer 41 covers at least a portion of the surface of the electrode lead-out portion 34 on the side opposite to the substrate 10 to encapsulate the electrode lead-out portion 34, thereby reducing the risk of impurities such as water and oxygen spreading to the battery structure through the electrode lead-out portion 34.

[0120] It should be noted that, in a direction parallel to the plane of the substrate 10, the electrode lead-out portion 34 can be disposed on one side of the corresponding battery assembly 20, and the corresponding first electrode 24 can overlap the side of the electrode lead-out portion 34 to achieve electrical connection. The electrode lead-out portion 34 can be disposed in the same layer as the first electrode 24.

[0121] Optionally, the extension direction of the electrode lead-out portion 34 and the extension direction of the busbar 35 can be parallel to each other, the arrangement direction of each battery assembly 20 and the arrangement direction of each battery cell can be perpendicular to the extension direction of the busbar 35, and the extension direction of the first electrode 24 of each battery cell can be parallel to the extension direction of the busbar 35, thereby helping to increase the overlap area between the electrode lead-out portion 34 and the corresponding first electrode 24 and improve the conductivity.

[0122] Preferably, the busbar 35 is disposed on the side of the electrode lead-out portion 34 away from the substrate 10, and the edge portion 412 covers a portion of the surface of the electrode lead-out portion 34 away from the substrate 10. Both the busbar 35 and the edge portion 412 are disposed on the side of the electrode lead-out portion 34 away from the substrate 10. The busbar 35 may be disposed in contact with the edge portion 412, or the busbar 35 may be disposed at a distance from the edge portion 412.

[0123] In this embodiment, since the corresponding first electrode 24 overlaps the side of the electrode lead-out portion 34, the corresponding first electrode 24 does not need to occupy the space on the side of the electrode lead-out portion 34 away from the substrate 10. Therefore, the side of the electrode lead-out portion 34 away from the substrate 10 has sufficient space for arranging the busbar 35 and the edge portion 412. When the contact area between the busbar 35 and the electrode lead-out portion 34 is constant, this application can increase the contact area between the electrode lead-out portion 34 and the edge portion 412, improve the encapsulation effect of the first barrier layer 41 on the electrode lead-out portion 34, and further reduce the risk of impurities such as water and oxygen spreading to the battery structure through the electrode lead-out portion 34.

[0124] Preferably, the electrode lead-out portion 34 is made of a metal oxide material, which has good density and can form a good sealing contact with the packaging structure 40, so as to further reduce the risk of impurities such as water and oxygen spreading to the battery structure.

[0125] Preferably, the electrode lead-out portion 34 includes at least one of fluorinated tin oxide, indium tin oxide, and indium zinc oxide to have excellent compactness, which helps to further improve the sealing performance of the encapsulation structure 40 to the battery structure.

[0126] In some optional embodiments, the electrode lead-out portion 34 is made of the same material as the first electrode 24. That is, the electrode lead-out portion 34 and the first electrode 24 can be disposed in the same layer and made of the same material, and the two can be formed in the same process, which helps to improve the connection reliability between the electrode lead-out portion 34 and the first electrode 24.

[0127] In some alternative embodiments, the material of the electrode lead-out portion 34 is different from the material of the first electrode 24, so that the materials of the electrode lead-out portion 34 and the first electrode 24 can be flexibly selected according to actual needs.

[0128] Preferably, the busbar 35 includes a busbar body and a conductive adhesive layer. The busbar body is bonded to the side of the electrode lead-out portion 34 away from the substrate 10 by the conductive adhesive layer, so as to improve the connection reliability between the busbar 35 and the electrode lead-out portion 34.

[0129] It should be noted that the second barrier layer 42 can cover the electrode lead-out portion 34 from the side facing the substrate 10, and the encapsulation layer 43 can cover the busbar 35 and a part of the electrode lead-out portion 34 from the side of the busbar 35 away from the substrate 10. The first barrier layer 41, the encapsulation layer 43 and the second barrier layer 42 can form a closed-loop sealing connection around the circumference of the electrode lead-out portion 34, which helps to further reduce the risk of impurities such as water and oxygen spreading to the battery structure.

[0130] like Figure 7 As shown, a second aspect of this application provides a method for fabricating a solar cell 100, which is used to fabricate the solar cell 100 described in any of the above-mentioned embodiments. The fabrication method includes: S10. A battery structure is formed on one side of the substrate 10. The battery structure includes multiple battery components 20. The multiple battery components 20 include a first battery component 21, a second battery component 22, and a third battery component 23. The first battery component 21 includes multiple first battery cells 211 arranged in series. The second battery component 22 includes at least one second battery cell 221. The third battery component 23 includes at least one third battery cell 231. The first battery cell 211, the second battery cell 221, and the third battery cell 231 all include a first electrode 24, a functional layer 25, and a second electrode 26 stacked in a direction away from the substrate 10. The third battery component 23 is disposed between the first battery component 21 and the second battery component 22. The first battery component 21 and the second battery component 22 are connected in parallel through the third battery component 23.

[0131] S20. A busbar structure 30 is formed on one side of the substrate 10. The busbar structure 30 includes a first busbar 31, a second busbar 32 and a third busbar 33. At least a portion of the first busbar 31 and at least a portion of the second busbar 32 are disposed in the same layer as the first electrode 24. The first busbar 31 is electrically connected to the first electrode 24 of the first battery assembly 21. The second busbar 32 is electrically connected to the first electrode 24 of the second battery assembly 22. A portion of the third busbar 33 covers the side of the second electrode 26 of the third battery assembly 23 away from the substrate 10 and is electrically connected to the second electrode 26 of the third battery assembly 23.

[0132] It should be noted that the order of steps S10 and S20 is not limited in the embodiments of this application. For example, the first busbar 31 and the second busbar 32 can be formed on one side of the substrate 10 first, then the battery structure can be fabricated, and finally the third busbar 33 can be formed. Alternatively, the battery structure can be fabricated on one side of the substrate 10 first, and then the busbar structure 30 can be fabricated.

[0133] In this embodiment, a battery structure is formed in step S20. The battery structure includes multiple battery components 20, each including a first battery component 21, a second battery component 22, and a third battery component 23. The first battery component 21 includes multiple first battery cells 211 connected in series. The second battery component 22 includes at least one second battery cell 221. The third battery component 23 includes at least one third battery cell 231. Each of the first battery cell 211, the second battery cell 221, and the third battery cell 231 includes a first electrode 24 stacked along a direction away from the substrate 10. The functional layer 25 and the second electrode 26, and the third battery module 23 are disposed between the first battery module 21 and the second battery module 22. The first battery module 21 and the second battery module 22 are connected in parallel through the third battery module 23. Therefore, there is no need to set up additional conductive parts for connecting the first battery module 21 and the second battery module 22 in parallel, which can simplify the structure of the solar cell 100 and reduce the assembly and maintenance difficulty of the solar cell 100. At the same time, the third battery module 23 can also perform photoelectric conversion, which is beneficial to improving the photoelectric conversion efficiency of the solar cell 100, thereby improving the performance of the solar cell 100. In step S20, a busbar structure 30 is formed. The busbar structure 30 includes a first busbar 31, a second busbar 32, and a third busbar 33. The first busbar 31 is electrically connected to the first electrode 24 of the first battery assembly 21, the second busbar 32 is electrically connected to the first electrode 24 of the second battery assembly 22, and the third busbar 33 is electrically connected to the second electrode 26 of the third battery assembly 23, so as to realize the electrode lead-out of each battery assembly 20 by using the first busbar 31, the second busbar 32, and the third busbar 33. Furthermore, at least a portion of the first busbar 31 and at least a portion of the second busbar 32 are disposed in the same layer as the first electrode 24, and a portion of the third busbar 33 covers the side of the second electrode 26 of the third battery assembly 23 away from the substrate 10. Thus, by reasonably arranging the positions of the first busbar 31, the second busbar 32 and the third busbar 33, the manufacturing and packaging difficulties of the first busbar 31, the second busbar 32 and the third busbar 33 are reduced, and the sealing performance of the solar cell 100 is improved.

[0134] Optionally, before steps S10 and S20, the method further includes forming a second barrier layer 42 on one side of the substrate 10. In steps S10 and S20, the battery structure and the bus structure 30 are formed on the side of the second barrier layer 42 opposite to the substrate 10.

[0135] Optionally, after steps S10 and S20, the method further includes forming a first barrier layer 41 and an encapsulation layer 43 on the side of the battery structure and busbar structure 30 away from the substrate 10, wherein the first barrier layer 41, the encapsulation layer 43 and the second barrier layer 42 together cover a portion of the battery structure and busbar structure 30.

[0136] Optionally, after forming the first barrier layer 41 and before forming the encapsulation layer 43, the method further includes forming a planarization layer 46 and a fourth barrier layer 45 on the side of the first barrier layer 41 facing away from the substrate 10.

[0137] Optionally, before steps S10 and S20, the method further includes: A third barrier layer 12 is formed on one side of the first substrate 11, and a second substrate 13 is formed on the side of the third barrier layer 12 facing away from the substrate 10. In steps S10 and S20, the battery structure and the bus structure 30 are located on the side of the second substrate 13 facing away from the first substrate 11.

[0138] While the embodiments disclosed in this application are as described above, the content is merely for the purpose of facilitating understanding of this application and is not intended to limit the invention. Any person skilled in the art to which this application pertains may make any modifications and changes in form and detail of the implementation without departing from the spirit and scope disclosed in this application; however, the scope of protection of this application shall still be determined by the scope defined in the appended claims.

[0139] The above description is merely a specific embodiment of this application. Those skilled in the art will clearly understand that, for the sake of convenience and brevity, substitutions for other connection methods described above can be made by referring to the corresponding processes in the foregoing method embodiments, and will not be repeated here. It should be understood that the scope of protection of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and these modifications or substitutions should all be covered within the scope of protection of this application.

Claims

1. A solar cell, characterized in that, include: substrate; A battery structure includes multiple battery components disposed on one side of the substrate. The multiple battery components include a first battery component, a second battery component, and a third battery component. The first battery component includes multiple first battery cells arranged in series. The second battery component includes at least one second battery cell. The third battery component includes at least one third battery cell. The third battery assembly is disposed between the first battery assembly and the second battery assembly, and the first battery assembly and the second battery assembly are connected in parallel through the third battery assembly.

2. The solar cell according to claim 1, characterized in that, The first battery cell, the second battery cell, and the third battery cell each include a first electrode, a functional layer, and a second electrode stacked along a direction away from the substrate. The second electrode of one first battery cell and the second electrode of one second battery cell are respectively electrically connected to the first electrode of the same third battery cell, so that the first battery assembly and the second battery assembly are connected in parallel through the first electrode of the third battery assembly. Preferably, the second battery assembly includes a plurality of second battery cells arranged in series; Preferably, the number of battery cells in the first battery assembly is equal to or different from the number of battery cells in the second battery assembly; Preferably, the material of the functional layer includes perovskite, cadmium telluride, copper indium gallium selenide, or organic photovoltaic materials; Preferably, a first opening is formed between the functional layer of the third battery cell and the functional layer of the adjacent first battery cell, and the second electrode of the first battery cell adjacent to the third battery cell extends to the first opening and is electrically connected to the corresponding first electrode. Preferably, a second opening is formed between the functional layer of the third battery cell and the functional layer of the adjacent second battery cell, and the second electrode of the adjacent second battery cell extends into the second opening and is electrically connected to the corresponding first electrode.

3. The solar cell according to claim 1, characterized in that, The solar cell further includes a current-collecting structure, which includes a first current-collecting element, a second current-collecting element, and a third current-collecting element. The first current-collecting element is electrically connected to the first battery module, the second current-collecting element is electrically connected to the second battery cell, and the third current-collecting element is electrically connected to the third battery module. The first current-collecting element and the second current-collecting element have the same polarity and opposite polarity to the third current-collecting element. Preferably, the first battery cell, the second battery cell, and the third battery cell each include a first electrode, a functional layer, and a second electrode stacked along a direction away from the substrate. The second electrode of one first battery cell and the second electrode of one second battery cell are respectively electrically connected to the first electrode of the same third battery cell, so that the first battery assembly and the second battery assembly are connected in parallel through the first electrode of the third battery assembly. Preferably, the first busbar is electrically connected to the first electrode of the first battery assembly, the second busbar is electrically connected to the first electrode of the second battery assembly, and the third busbar is electrically connected to the second electrode of the third battery assembly. Preferably, at least a portion of the first busbar and at least a portion of the second busbar are disposed in the same layer as the first electrode; Preferably, along a direction parallel to the plane of the substrate, the first busbar is disposed on one side of the first battery assembly, and the first electrode of the first battery assembly is connected to the side of the first busbar near the first battery assembly. The second busbar is disposed on one side of the second battery assembly, and the first electrode of the second battery assembly is connected to the side of the second busbar closer to the second battery assembly; Preferably, along a direction parallel to the plane where the substrate is located, the first busbar and the second busbar are respectively disposed on both sides of the battery structure, the first busbar being located on the side of the first battery assembly away from the second battery assembly, and the second busbar being located on the side of the second battery assembly away from the first battery assembly; Preferably, a portion of the third busbar covers the side of the second electrode of the third battery cell that faces away from the substrate; Preferably, there are multiple first battery components, multiple second battery components, and multiple third battery components, with multiple first battery components and multiple second battery components arranged alternately, and a third battery component is provided between adjacent first battery components and second battery components and connected in parallel through the third battery component; Preferably, there are multiple third busbars, and the multiple third busbars are electrically connected to multiple third battery assemblies; among the multiple first battery assemblies and multiple second battery assemblies, one first battery assembly is located on one side edge of the battery structure and is electrically connected to the first busbar, and one second battery assembly is located on the opposite side edge of the battery structure and is electrically connected to the second busbar.

4. The solar cell according to claim 3, characterized in that, The solar cell further includes an encapsulation structure that covers a portion of the cell structure and the busbar structure. Preferably, the encapsulation structure includes a first barrier layer, the first barrier layer including a main body portion and an edge portion, the main body portion covering the side of the battery structure away from the substrate, the edge portion being disposed on at least two sides of the main body portion, and the edge portion covering at least a portion of the surface of the first busbar facing away from the substrate and at least a portion of the surface of the second busbar facing away from the substrate. Preferably, the main body covers the third busbar; Preferably, a portion of the first electrode closest to the first busbar in the first battery assembly extends out of the functional layer, and the edge portion covers a portion of the first electrode. Preferably, a portion of the first electrode closest to the second busbar in the second battery assembly extends out of the functional layer, and the edge portion covers a portion of the first electrode.

5. The solar cell according to claim 4, characterized in that, The encapsulation structure further includes a second barrier layer, which is disposed between the substrate and the battery assembly, and covers the first busbar and the side of the second busbar closest to the substrate. Preferably, the material of the first barrier layer is the same as or different from that of the second barrier layer; Preferably, the first barrier layer and / or the second barrier layer comprise inorganic materials; Preferably, the first barrier layer and / or the second barrier layer comprises at least one of silicon nitride, silicon oxide, and aluminum oxide; Preferably, the substrate includes a first substrate, a third barrier layer and a second substrate stacked together, wherein the second barrier layer is disposed on the side of the second substrate opposite to the first substrate.

6. The solar cell according to claim 4, characterized in that, The first barrier layer forms a first through hole along a direction parallel to the substrate. The first through hole is located on one side of the second electrode of the third battery cell, and a portion of the third busbar passes through the first through hole. Preferably, the encapsulation structure further includes an encapsulation layer covering the first barrier layer, the encapsulation layer forming a second through hole, the second through hole communicating with the first through hole, and a portion of the third busbar passing through the second through hole; Preferably, the encapsulation structure further includes a dispensing encapsulation part, which is located in the second through hole and is disposed around the third busbar, and the side of the dispensing encapsulation part near the first through hole is connected to the first barrier layer. Preferably, the material of the dispensing and encapsulation portion includes at least one of organosilicon, nano-silica, and crosslinking agent.

7. The solar cell according to claim 6, characterized in that, The encapsulation layer also covers a portion of the bus structure; Preferably, the encapsulation structure further includes a second barrier layer disposed between the substrate and the battery assembly, and the encapsulation layer further covers a portion of the second barrier layer and is connected to the second barrier layer; Preferably, the material of the encapsulation layer includes at least one of polyolefin elastomer, ethylene-vinyl acetate copolymer, and epoxy resin; Preferably, the solar cell further includes a cover plate disposed on the side of the encapsulation layer opposite to the substrate, and the cover plate is connected to the encapsulation layer.

8. The solar cell according to any one of claims 4-7, characterized in that, The packaging structure further includes a fourth barrier layer, which is disposed on the side of the first barrier layer away from the substrate; Preferably, the packaging structure further includes a planarization layer disposed between the first barrier layer and the fourth barrier layer; Preferably, the fourth barrier layer covers the side surface of the planarization layer opposite to the substrate and the side surface of the planarization layer, and is connected to the first barrier layer on the side surface.

9. The solar cell according to any one of claims 4-8, characterized in that, At least one of the first busbar and the second busbar includes an electrode lead-out portion and a busbar, the electrode lead-out portion being electrically connected to the first electrode, the busbar being electrically connected to the electrode lead-out portion, and the edge portion of the first barrier layer covering at least a portion of the surface of the electrode lead-out portion on the side away from the substrate. Preferably, the busbar is disposed on the side of the electrode lead-out portion away from the substrate, and the edge portion covers a portion of the surface of the electrode lead-out portion away from the substrate; Preferably, the electrode lead-out portion comprises a metal oxide material; Preferably, the electrode lead-out portion includes at least one of fluorine-doped tin oxide, indium tin oxide, and indium zinc oxide; Preferably, the material of the electrode lead-out portion is the same as or different from the material of the first electrode; Preferably, the busbar includes a bus body and a conductive adhesive layer, wherein the bus body is bonded to the side of the electrode lead-out portion away from the substrate by the conductive adhesive layer.

10. A method for preparing a solar cell, characterized in that, The preparation method is used to prepare the solar cell according to any one of claims 1-9, and the preparation method includes: A battery structure is formed on one side of a substrate. The battery structure includes multiple battery components, including a first battery component, a second battery component, and a third battery component. The first battery component includes multiple first battery cells arranged in series. The second battery component includes at least one second battery cell. The third battery component includes at least one third battery cell. Each of the first, second, and third battery cells includes a first electrode, a functional layer, and a second electrode stacked in a direction away from the substrate. The third battery component is disposed between the first and second battery components. The first and second battery components are connected in parallel through the third battery component. A busbar structure is formed on one side of the substrate. The busbar structure includes a first busbar, a second busbar, and a third busbar. At least a portion of the first busbar and at least a portion of the second busbar are disposed on the same layer as the first electrode. The first busbar is electrically connected to the first electrode of the first battery assembly. The second busbar is electrically connected to the first electrode of the second battery assembly. A portion of the third busbar covers the side of the second electrode of the third battery assembly facing away from the substrate and is electrically connected to the second electrode of the third battery assembly.

Images