Solar cell and manufacturing method of the same, photovoltaic module, and photovoltaic system

Abstract

To provide a solar cell and its manufacturing method, a photovoltaic module, and a photovoltaic system.SOLUTION: A solar cell includes: a base substrate including a first surface and a second surface arranged oppositely, and a plurality of adjacent side faces between the first surface and the second surface; a dope conductive layer and a first passivation film layer sequentially installed in lamination on the first surface to cover only the first surface; an antireflection film layer installed in lamination on the first passivation film layer and for covering the first surface so as to cover at least the first passivation film layer; a passivation contact layer provided on the second surface; and a second passivation film layer installed in lamination on the passivation contact layer and for covering the second surface so as to cover at least the passivation contact layer. The antireflection film layer covers at least a portion of each side face, or the second passivation film layer covers at least a portion of each side face.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to the technical field of solar cells, and in particular to a solar cell and its manufacturing method, a photovoltaic module and a photovoltaic system. [Background technology]

[0002] With the rapid development of photovoltaic industry technology, the domestic and foreign markets have increasingly high requirements for the conversion efficiency of solar cells, and many manufacturers in the industry are actively developing and researching high-efficiency cells. Among them, surface passivation contact technology has become the focus of research in the industry in recent years. TOPCon (Tunnel Oxide Passivated Contact) technology is a technology that fabricates an ultra-thin tunnel oxide layer and a doped polycrystalline silicon thin layer on the surface of a cell, which together form a passivation contact structure, thereby greatly reducing the metal contact recombination current and improving the open circuit voltage and short circuit current of the cell. However, in the TOPCon cell according to the related technology, there is a large amount of carrier recombination on the edge surface of the cell, which reduces the efficiency of the solar cell. Summary of the Invention [Problem to be solved by the invention]

[0003] In view of the above problems, the present application provides a solar cell and a manufacturing method thereof, a photovoltaic module, and a photovoltaic system that can improve the efficiency of the solar cell. [Means for solving the problem]

[0004] The embodiment of the present invention is A base substrate including a first surface and a second surface disposed opposite to each other and a plurality of side surfaces adjacent to the first surface and the second surface; a doped conductive layer and a first passivation film layer, which are stacked on the first surface and cover only the first surface; an anti-reflection film layer disposed on the first passivation film layer, the anti-reflection film layer covering the first surface so as to cover at least the first passivation film layer; a passivation contact layer disposed on the second surface; a second passivation film layer disposed on the passivation contact layer, the second passivation film layer covering the second surface so as to cover at least the passivation contact layer; Including, The anti-reflective coating layer further covers at least a portion of at least one side surface, or the second passivation coating layer further covers at least a portion of at least one side surface. A solar cell is provided.

[0005] By having the anti-reflective coating layer further cover at least a portion of at least one side surface, or by having the second passivation coating layer further cover at least a portion of at least one side surface, at least a portion of the area of ​​at least one side surface of the underlying substrate is protected by the anti-reflective coating or the second passivation coating layer, thereby passivating the edge surface of the solar cell corresponding to that side surface, and reducing carrier recombination on the edge surface of the solar cell to improve the efficiency of the solar cell.

[0006] Preferably, the anti-reflective coating layer covers at least a portion of each side surface, or the second passivation coating layer covers at least a portion of each side surface.

[0007] Preferably, the anti-reflective coating layer completely covers at least each side surface, and At least the surface of the passivation contact layer located on the same side as the side in question is completely covered.

[0008] Preferably, the anti-reflective coating layer further covers at least a portion of the area adjacent to the side of the second surface, Alternatively, the edge of the antireflective coating layer proximate the second surface is flush with the surface of the passivation contact layer remote from the underlying substrate.

[0009] Preferably, the second passivation film layer covers at least a portion of the anti-reflective coating layer.

[0010] Preferably, the side surface of the base substrate is flush with edges of the doped conductive layer, the first passivation film layer, and the anti-reflection film layer that are located on the same side as the side surface in a normal direction of the side surface; the second passivation film layer has a portion of the structure on each side and completely covers at least each side; The doped conductive layer completely covers at least the doped conductive layer, the first passivation film layer, and the edges of the anti-reflection film layer on the same side as the respective side surfaces.

[0011] Preferably, the second passivation film layer further covers at least a portion of the first surface adjacent each side thereof, Alternatively, an edge of the second passivation layer proximate to the first surface is flush with an outer surface along the thickness direction of the underlying substrate of the anti-reflective coating layer.

[0012] The embodiment of the present invention further comprises: Providing a substrate including a base substrate having a first surface and a second surface disposed opposite to each other and a plurality of side surfaces adjacent between the first surface and the second surface, a doped conductive layer and a first passivation film layer sequentially stacked on the first surface and covering only the first surface, and a passivation contact layer provided on the second surface; forming an anti-reflective coating layer on the first passivation film layer, the anti-reflective coating layer covering the first surface, at least covering the first passivation film layer; forming a second passivation film layer over the second surface on the passivation contact layer so as to completely cover the passivation contact layer; The anti-reflective coating layer or the second passivation coating layer further covers at least a portion of at least one side surface. A method for manufacturing a solar cell is provided.

[0013] Preferably, the step of forming an anti-reflective coating layer on the first passivation film layer includes: The substrate is engaged and placed between the positioning protrusions provided on the positioning boat with the passivation contact layer of the substrate facing the positioning boat, and an anti-reflective material is formed on a first unmasked surface area of ​​the substrate; adjusting a relative position between each of the positioning protrusions and a side surface of the underlying substrate to form a second unshielded surface area of ​​the substrate, and forming an anti-reflective material on the second unshielded surface area of ​​the substrate to form an anti-reflective coating layer on the first passivation film layer; The anti-reflective coating layer covers at least the first passivation film layer, each side surface and a surface of the passivation contact layer located on the same side as the side surfaces.

[0014] Preferably, when the passivation contact layer of the substrate is attached to the positioning boat, an edge of the formed anti-reflection film layer close to the second surface is flush with a surface of the passivation contact layer that is away from the underlying substrate; With the passivation contact layer of the substrate spaced apart from the positioning board, the anti-reflection film layer formed further covers at least a portion of an area adjacent to a side surface of the passivation contact layer.

[0015] Preferably, the side surface of the base substrate is flush with edges of the doped conductive layer, the first passivation film layer, and the anti-reflection film layer that are located on the same side as the side surface in a normal direction of the side surface; The first structure is a substrate on which an anti-reflective coating layer is formed, The step of forming a second passivation film layer on the passivation contact layer includes: With the anti-reflective coating layer facing the positioning boat, the first structure is engaged and placed between the positioning protrusions provided on the positioning boat, and a second passivation material is formed on a first unmasked surface area of ​​the first structure; adjusting a relative position between each positioning protrusion and a side surface of the underlying substrate to form a second unshielded surface area of ​​the first structure, and forming a second passivation material on the second unshielded surface area of ​​the first structure to form a second passivation film layer on the passivation contact layer; The second passivation layer completely covers at least each side of the underlying substrate, and completely covers at least the doped conductive layer, the first passivation layer, and edges of the anti-reflective coating layer on the same side as each side.

[0016] Preferably, when the anti-reflection coating layer is attached to the positioning boat, an edge of the formed second passivation coating layer close to the first surface is flush with an outer surface of the anti-reflection coating layer along a thickness direction of the base substrate; With the anti-reflective coating layer spaced apart from the positioning boat, the formed second passivation coating layer further covers at least a portion of the area adjacent to each side of the first surface.

[0017] Preferably, the step of providing a substrate comprises: forming a doped conductive layer on a first surface of an underlying substrate; forming a passivation contact layer on the second surface of the underlying substrate; and forming a first passivation layer over the doped conductive layer.

[0018] An embodiment of the present invention further provides a photovoltaic module including at least one cell string including the solar cell described above.

[0019] An embodiment of the present invention further provides a photovoltaic system including the above-described photovoltaic module. [Brief description of the drawings]

[0020] [Figure 1] FIG. 1 is a schematic diagram showing the configuration of a solar cell provided in an embodiment of the present application. [Diagram 2] FIG. 2 is a schematic diagram showing the configuration of a solar cell according to another embodiment of the present application. [Diagram 3] FIG. 2 is a schematic diagram showing the configuration of a solar cell according to another embodiment of the present application. [Figure 4] FIG. 2 is a schematic diagram showing the configuration of a solar cell according to another embodiment of the present application. [Diagram 5]FIG. 1 is a schematic flow diagram of a method for manufacturing a solar cell according to an embodiment of the present invention. [Figure 6] 1 is a schematic diagram showing the configuration of a positioning device in a solar cell manufacturing method according to an embodiment of the present invention; [Figure 7] 1 is a schematic diagram showing the configuration of a substrate in a solar cell manufacturing method provided by an embodiment of the present invention. [Figure 8] FIG. 2 is a schematic diagram showing the formation of an anti-reflective coating layer in a solar cell manufacturing method according to an embodiment of the present invention. [Figure 9] FIG. 2 is a schematic diagram showing the formation of a second passivation film layer in the solar cell manufacturing method provided by an embodiment of the present invention. [Figure 10] FIG. 2 is a schematic diagram showing the formation of an anti-reflective coating layer in a method for manufacturing a solar cell according to another embodiment of the present invention. [Figure 11] FIG. 2 is a schematic diagram showing the formation of a second passivation film layer in a solar cell manufacturing method according to another embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] In order to make the above-mentioned objects, features and advantages of the present invention more easily comprehensible, the specific embodiments of the present invention will be described in detail with reference to the drawings. In order to fully understand the present invention, various specific details are set forth in the following description. However, the present invention can be embodied in various forms different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention, and therefore the present invention is not limited to the specific embodiments disclosed below.

[0022] Furthermore, the terms "first" and "second" are for descriptive purposes only and should not be understood to indicate or suggest a relative importance or to imply a number of technical features being presented. Thus, a feature qualified as "first" or "second" may explicitly or implicitly include at least one of said feature. In the present description, unless otherwise expressly and specifically limited, "plurality" means at least two, e.g., two, three, etc.

[0023] In the present invention, unless otherwise clearly specified and limited, the terms "attached", "coupled", "connected", "fixed" and the like should be interpreted in a broad sense, and unless otherwise clearly limited, they may be, for example, fixed connection, detachable connection, or integral, mechanical connection, electrical connection, direct connection, indirect connection through an intermediate medium, internal communication between two elements, or an interactive relationship between two elements. Those skilled in the art may understand the specific meaning of the above terms in the present invention according to the specific circumstances.

[0024] Hereinafter, a solar cell and a manufacturing method thereof, a photovoltaic module, and a photovoltaic system according to the present embodiment will be described with reference to the accompanying drawings.

[0025] In the related art, there is a problem that the recombination loss on the edge surface of the solar cell is relatively large, resulting in low efficiency of the solar cell. In the present invention, the contact position between the base substrate and the positioning device during the film formation process is adjusted to deposit the anti-reflection film layer or the second passivation film layer on the side surface of the base substrate, thereby reducing the recombination on the edge surface of the solar cell and improving the photoelectric conversion efficiency.

[0026] Referring to FIG. 1, an embodiment of the present invention provides a solar cell 1, which includes an underlying substrate 2, a doped conductive layer 3, a first passivation film layer 4, an anti-reflective coating layer 5, a passivation contact layer 6 and a second passivation film layer 7.

[0027] The base substrate 2 includes a first surface 11 and a second surface 12 disposed opposite to each other, and a plurality of side surfaces 13 adjacent between the first surface 11 and the second surface 12. The doped conductive layer 3 and the first passivation film layer 4 are laminated on the first surface 11 in order, and cover only the first surface 11. The anti-reflection film layer 5 is laminated on the first passivation film layer 4. The anti-reflection film layer 5 covers the first surface 11 so as to cover at least the first passivation film layer 4. The passivation contact layer 6 is provided on the second surface 12. The second passivation film layer 7 is laminated on the passivation contact layer 6. The second passivation film layer 7 covers the second surface 12 so as to cover at least the passivation contact layer 6. Moreover, the anti-reflection film layer 5 further covers at least a part of at least one side surface 13, or the second passivation film layer 7 further covers at least a part of at least one side surface 13. In the present invention, one film layer covering another structural layer includes a case where the film layer is directly laminated on the other structural layer, or a case where the film layer is provided on the other structural layer via the other structural layer, and the term "covering" is used only to limit the installation range of the one film layer.

[0028] At least a portion of the area of ​​at least one side surface 13 of the base substrate 2 is protected by the anti-reflective coating layer 5 or the second passivation coating layer 7, so that the edge surface of the solar cell 1 corresponding to the side surface 13 can be passivated, reducing recombination at the edge surface of the solar cell 1 and improving the efficiency of the solar cell 1. In some embodiments, the anti-reflective coating layer 5 covers at least a portion of each side surface 13, or the second passivation coating layer 7 covers at least a portion of each side surface 13.

[0029] The doped conductive layer 3 is used to form a PN junction with the base substrate 2. In this embodiment, the doped conductive layer 3 is a P-type doped conductive layer 3 (doped with boron) as an example, and the description of other doped conductive layers 3 is similar to this, so that the description will not be repeated here.

[0030] The first passivation film layer 4 performs a surface passivation function, and may be, for example, an aluminum oxide passivation layer, which is used to provide good passivation for the dangling bonds on the surface of the underlying substrate 2 .

[0031] The doped conductive layer 3 and the first passivation film layer 4 being laminated in order on the first surface 11 means that the doped conductive layer 3 is provided on the first surface 11, and the first passivation film layer 4 is laminated on the side of the doped conductive layer 3 that is away from the first surface 11. The doped conductive layer 3 and the first passivation film layer 4 covering only the first surface 11 means that the installation range of the doped conductive layer 3 and the first passivation film layer 4 is limited to only the first surface 11, and is not provided on other surfaces of the base substrate 2.

[0032] The anti-reflective coating layer 5 covers the first surface 11 and also covers at least a portion of at least one side surface 13, for example, covers at least a portion of each side surface 13, for example, the installation range of the anti-reflective coating layer 5 not only covers the first surface 11 but also extends further and may be laminated directly on each side surface 13 of the base substrate 2. The anti-reflective coating layer 5 reduces reflection loss of light on the surface of the solar cell 1, improving the conversion efficiency of the cell. The anti-reflective coating layer 5 may have a single layer or a multi-layer structure, and may be made of one or more materials selected from the group consisting of silicon oxide, silicon nitride, and silicon oxynitride.

[0033] In another possible embodiment, the second passivation film layer 7 covers the second surface 12 and also covers at least a part of at least one side surface 13, for example, covers at least a part of each side surface 13, for example, the installation range of the second passivation film layer 7 may not only cover the second surface 12 but also extend further and be directly laminated on each side surface 13 of the base substrate 2. The second passivation film layer 7 may also have a single layer or a multi-layer structure. The material of the second passivation film layer 7 may be one or more of silicon oxide, silicon nitride, or silicon oxynitride. The second passivation film layer 7 may include at least one anti-reflection material layer laminated on the passivation contact layer 6. In this way, the reflectance of the back surface of the solar cell 1 to sunlight is reduced and the absorption rate of the back surface of the solar cell 1 to sunlight is improved, so that the second passivation film layer 7 simultaneously performs the functions of passivation and anti-reflection.

[0034] As described above, the anti-reflective coating layer 5 may be directly laminated on each side surface 13 of the base substrate 2, or the anti-reflective coating layer 5 may completely cover at least each side surface 13 and completely cover at least the surface of the passivation contact layer 6 located on the same side as the side surface 13 in order to passivate the entire side surface 13 with respect to the installation range of the anti-reflective coating layer 5 on the side surface 13 of the base substrate 2. In this way, it is possible to cover all the places where carrier recombination may occur on the edge surface of the solar cell 1, thereby preventing carrier recombination and electrical leakage on the edge surface of the solar cell 1 and improving the efficiency of the solar cell 1.

[0035] By way of example, and referring to FIG. 1 , in a possible embodiment, the edge of the anti-reflective coating layer 5 proximate the second surface 12 is flush with the surface of the passivation contact layer 6 away from the underlying substrate 2, i.e., flush with the outer surface of the passivation contact layer 6 in the thickness direction along the underlying substrate 2.

[0036] 2, the anti-reflective coating layer 5 further covers at least a portion of the area adjacent to the side surface 13 of the second surface 12. At this time, the anti-reflective coating layer 5 is laminated on the passivation contact layer 6 in a portion of the area, thereby protecting the side surface 13 of the entire base substrate 2 and the side surface of the passivation contact layer 6. As can be seen, at this time, a passivation field can be formed at the edge of the second surface 12 as well, thereby effectively reducing the recombination center of the second surface 12 of the base substrate 2.

[0037] Furthermore, the second passivation film layer 7 covers at least a part of the anti-reflection film layer 5, and in the case shown in FIG. 1, the second passivation film layer 7 covers the edge of the anti-reflection film layer 5 on the side close to the second surface 12. In the case shown in FIG. 2, the second passivation film layer 7 has a part of a structure laminated on the anti-reflection film layer 5, and the thickness of the laminated region of the second passivation film layer 7 and the anti-reflection film layer 5 of the solar cell 1 is larger than the thickness of the central part of the solar cell 1, and the thickness difference here may be, for example, 5 nm to 1 μm (including the end point value). In this way, it is possible to ensure that the film layer is effectively deposited on the side surface 13 and the edge of the second surface 12 of the base substrate 2, form a passivation field, and reduce carrier recombination on the surface of the base substrate 2.

[0038] In some embodiments, the side surface 13 of the undersubstrate 2 is flush with the edge of the passivation contact layer 6 located on the same side as the side surface 13 in the normal direction of the side surface 13, i.e., the installation range of the passivation contact layer 6 is limited to only the second surface 12 and does not extend to the side surface 13 of the undersubstrate 2. The passivation contact layer 6 may include a tunnel oxide layer 61 and a doped polysilicon conductive layer 62 stacked in order on the second surface. In addition, the tunnel oxide layer 61 is used to perform interface passivation of the second surface 12 of the undersubstrate 2, and achieves the effect of chemical passivation. The material of the tunnel oxide layer 61 may be a dielectric material, such as silicon oxide.

[0039] 3 and 4, the side surface 13 of the base substrate 2 is flush with the edges of the doped conductive layer 3, the first passivation film layer 4, and the anti-reflective film layer 5 located on the same side as the side surface 13 in the normal direction of the side surface 13, and the second passivation film layer 7 has a partial structure on each side surface 13, completely covers at least each side surface 13, and completely covers at least the doped conductive layer 3, the first passivation film layer 4, and the edges of the anti-reflective film layer 5 located on the same side as the side surface 13. Exemplarily, the second passivation film layer 7 is directly laminated on each side surface 13, thereby protecting each side surface 13, and further completely covers at least the doped conductive layer 3, the first passivation film layer 4, and the edges of the anti-reflective film layer 5 located on the same side as the side surface 13, thereby providing good passivation to the side surfaces of the solar cell 1.

[0040] In a specific implementation, as shown in FIG. 3, the edge of the second passivation film layer 7 close to the first surface 11 may be flush with the outer surface of the anti-reflective film layer 5 along the thickness direction of the underlying substrate 2.

[0041] Alternatively, as shown in FIG. 4, the second passivation film layer 7 may further cover at least a part of the area adjacent to each side surface 13 of the first surface 11. In this case, the second passivation film layer 7 has a part of the structure laminated on the edge portion of the anti-reflection film layer 5 on the first surface 11, and the thickness of the laminated area of ​​the second passivation film layer 7 and the anti-reflection film layer 5 of the solar cell 1 is larger than the thickness of the central portion of the solar cell 1, and the thickness difference here may be, for example, 5 nm to 1 μm (including the end point value). As can be seen, in this case, a passivation field is similarly formed at the edge portion of the first surface 11, effectively reducing the recombination center of the first surface 11 of the base substrate 2. In addition, a film layer is effectively deposited on the edge between the side surface 13 and the first surface 11 of the base substrate 2, forming a passivation field, protecting the surface of the base substrate 2 and reducing carrier recombination.

[0042] An embodiment of the present invention further provides a method for manufacturing a solar cell, the method for manufacturing a solar cell including:

[0043] S1, a substrate 10 is provided. The substrate 10 includes a base substrate 2, a doped conductive layer 3, a first passivation film layer 4, and a passivation contact layer 6. The base substrate 2 includes a first surface 11 and a second surface 12 arranged opposite to each other, and a plurality of side surfaces 13 adjacent to each other between the first surface 11 and the second surface 12, the doped conductive layer 3 and the first passivation film layer 4 are stacked in order on the first surface 11 and cover only the first surface 11, and the passivation contact layer 6 is provided on the second surface 12.

[0044] In S2, an anti-reflection film layer 5 is formed on the first passivation film layer 4 so as to cover at least the first passivation film layer 4 and to cover the first surface 11.

[0045] S3, a second passivation film layer 7 is formed on the passivation contact layer 6 to cover the second surface 12 so as to completely cover the passivation contact layer 6. The anti-reflective coating layer 5 or the second passivation film layer 7 further covers at least a portion of at least one side surface 13.

[0046] At least a portion of the area of ​​at least one side surface 13 of the base substrate 2 is protected by the anti-reflective coating layer 5 or the second passivation coating layer 7, and the edge surface of the solar cell 1 corresponding to the side surface 13 can be passivated to reduce recombination on the edge surface of the solar cell 1 and improve the efficiency of the solar cell 1. In some embodiments, the anti-reflective coating layer 5 covers at least a portion of each side surface 13, or the second passivation coating layer 7 covers at least a portion of each side surface 13.

[0047] In some embodiments, in the manufacturing process of the solar cell 1, the substrate 10 is positioned by a positioning device. The positioning device may include a plurality of positioning boats 8 and a plurality of positioning protrusions 9 arranged in parallel. FIG. 6 shows a schematic diagram of one of the positioning boats 8. As shown in FIG. 6, the substrate 10 can be locked and fixed to the positioning boat 8 by a plurality of positioning protrusions 9 provided around the substrate 10. The positioning protrusions 9 are fixed to the positioning boat 8 and also contact each side surface 13 of the substrate 10 and a surface of the substrate 10 that is away from the positioning boat 8, thereby positioning the substrate 10. Here, the positioning device may be a graphite boat.

[0048] Furthermore, step S3 further includes a step of forming a second passivation film layer 7 on the passivation contact layer 6, and then forming electrodes on the anti-reflection coating layer 5 and the second passivation film layer 7, respectively.

[0049] Further, in step S1, the step of providing a substrate 10 includes: forming a doped conductive layer 3 on a first surface 11 of an underlying substrate 2; forming a passivation contact layer 6 on a second surface 12 of the underlying substrate 2; forming a first passivation layer 4 on the doped conductive layer 3.

[0050] Further, referring to FIG. 6, FIG. 7 and FIG. 8, in step S2, the step of forming the anti-reflection film layer 5 on the first passivation film layer 4 includes: The substrate 10 is engaged and placed between the positioning protrusions 9 provided on the positioning board 8 while the passivation contact layer 6 of the substrate 10 faces the positioning board 8, and an anti-reflection material is formed on a first unshielded surface area of ​​the substrate 10; adjusting the relative positions of each positioning protrusion 9 and the side surface 13 of the base substrate 2 to form a second unshielded surface area of ​​the substrate 10, forming an anti-reflective material on the second unshielded surface area of ​​the substrate 10, and forming an anti-reflective film layer 5 on the first passivation film layer 4; The anti-reflection film layer 5 covers at least the first passivation film layer 4 , each side surface 13 , and a surface of the passivation contact layer 6 located on the same side as the side surface 13 .

[0051] 6, the relative position of each positioning protrusion 9 and the side surface 13 of the base substrate 2 may be adjusted, and the positioning protrusion 9 may be moved relative to its original position, i.e., the area originally covered by the positioning protrusion 9 may be exposed to form a second uncovered surface area, and the anti-reflection coating layer 5 may be manufactured. For example, the positioning protrusions 9 located on both the left and right sides of the substrate 10 in FIG. 6 (the left and right sides of the drawing in FIG. 6) may be lowered or raised, and the positioning protrusions 9 located on the bottom side of the substrate 10 in FIG. 6 (the lower side of the drawing in FIG. 6) may be moved to both the left and right sides. Such position adjustment may be performed once or multiple times.

[0052] The substrate 10 may be completely attached to the positioning boat 8, or may be spaced apart from the positioning boat 8. Specifically, when the passivation contact layer 6 of the substrate 10 is attached to the positioning boat 8, the edge of the formed anti-reflection film layer 5 close to the second surface 12 is flush with the surface of the passivation contact layer 6 away from the base substrate 2, i.e., the anti-reflection film layer 5 is not formed on the passivation contact layer 6 (is not shielded by the positioning boat 8).

[0053] With the passivation contact layer 6 of the substrate 10 spaced apart from the positioning boat 8, the formed anti-reflection film layer 5 further covers at least a portion of the area adjacent to the side surface 13 of the passivation contact layer 6, and a portion of the edge of the passivation contact layer 6 is exposed to the reaction gas atmosphere, so that the anti-reflection film layer 5 is also formed on a portion of the edge of the passivation contact layer 6, as shown in Fig. 2. Naturally, in this case, in the subsequent step of forming the second passivation film layer 7, the second passivation film layer 7 will cover the film layer on the side located at the second surface 12 of the anti-reflection film layer 5.

[0054] After the step of forming the passivation contact layer 6, the method further includes a step of forming a second passivation film layer 7 on the passivation contact layer 6, to form the structure shown in FIG.

[0055] Hereinafter, a specific example will be taken to describe the manufacturing method of the solar cell of this embodiment, which includes the following:

[0056] In step (A), the base substrate 2 is textured, boron doped, and alkaline polished to form a textured structure and a doped conductive layer 3 on the first surface 11 of the base substrate 2 .

[0057] Step (B): depositing a tunnel material layer and an amorphous silicon material layer on the underlying substrate 2, and performing phosphorus element doping and etching to form a passivation contact layer 6 on the second surface 12 of the underlying substrate 2, and depositing aluminum oxide on the doped conductive layer 3 to form a first passivation film layer 4, thereby forming the substrate 10 shown in FIG. 7.

[0058] In step (C), with the passivation contact layer 6 of the substrate 10 facing the positioning board 8 and spaced apart from the positioning board 8, the substrate 10 is engaged and placed between each of the positioning protrusions 9 provided on the positioning board 8, and an anti-reflective material is formed on the unshielded surface area of ​​the substrate 10.

[0059] The relative positions of each positioning protrusion 9 and the side surface 13 of the base substrate 2 are adjusted, and then an anti-reflective material is formed on the unobstructed surface area of ​​the substrate 10 to form an anti-reflective coating layer 5 on the first passivation film layer 4. As shown in Fig. 8, the anti-reflective coating layer 5 covers the first passivation film layer 4, each side surface 13, a surface of the passivation contact layer 6 located on the same side as the side surface 13, and a part of the surface of the passivation contact layer 6 adjacent to the side surface 13 of the base substrate 2.

[0060] In step (D), a second passivation film layer 7 is formed on the passivation contact layer 6, and electrodes are formed on the anti-reflection film layer 5 and the second passivation film layer 7, as shown in FIG. 9, electricity is injected, and a test screening is performed.

[0061] In some other embodiments, referring to Figures 3, 4, 10 and 11, when the side 13 of the base substrate 2 is flush with the edges of the doped conductive layer 3, the first passivation film layer 4 and the anti-reflective film layer 5 located on the same side as the side 13 in the normal direction of the side 13, i.e., when the formed anti-reflective film layer 5 covers only the first surface 11, the step of forming the second passivation film layer 7 on the passivation contact layer 6 includes:

[0062] With the anti-reflective film layer 5 facing the positioning boat 8, the first structure is engaged and placed between the positioning protrusions 9 provided on the positioning boat 8, and a second passivation material is formed on the first unshielded surface area of ​​the first structure. The first structure is a substrate 10 on which an anti-reflective coating layer 5 is formed.

[0063] The relative positions of each positioning protrusion 9 and the side surface 13 of the base substrate 2 are adjusted to form a second unshielded surface region of the first structure, and a second passivation material is subsequently deposited to form a second passivation material on the second unshielded surface region of the first structure, thereby forming a second passivation film layer 7 on the passivation contact layer 6. The second passivation film layer 7 completely covers at least each side 13 of the base substrate 2, and also completely covers at least the edges of the doped conductive layer 3, the first passivation film layer 4, and the anti-reflective film layer 5 that are located on the same side as each side 13.

[0064] In this process, referring to Fig. 6, the relative position of each positioning protrusion 9 and the side surface 13 of the base substrate 2 is adjusted, and the positioning protrusion 9 is moved relative to its original position, i.e., the portion shielded by the positioning protrusion 9 is exposed, forming a second unshielded surface region to manufacture the second passivation film layer 7. For example, the positioning protrusions 9 located on both the left and right sides of the substrate 10 in Fig. 6 (both the left and right sides of the drawing in Fig. 6) can be lowered or raised, and the positioning protrusions 9 located on the bottom side of the substrate 10 in Fig. 6 (the lower side of the drawing in Fig. 6) can be moved to both the left and right sides. Such position adjustment may be performed once or multiple times.

[0065] The substrate 10 may be completely attached to the positioning boat 8, or may be spaced apart from the positioning boat 8. Specifically, when the anti-reflection coating layer 5 is attached to the positioning boat 8, the edge of the formed second passivation film layer 7 close to the first surface 11 is flush with the outer surface of the anti-reflection coating layer 5 along the thickness direction of the base substrate 2, forming the structure shown in FIG.

[0066] With the anti-reflective coating layer 5 spaced apart from the positioning board 8, the formed second passivation coating layer 7 further covers at least a portion of the areas adjacent to each side 13 of the first surface 11, forming the structure shown in Figure 4.

[0067] Hereinafter, a specific embodiment will be given to describe another method for manufacturing the solar cell 1, which includes the following:

[0068] In step (E), the underlying substrate 2 is textured, boron doped, and alkaline polished to form a texturing structure and a doped conductive layer 3 on the first surface 11 of the underlying substrate 2 .

[0069] Step (F) is depositing a tunnel material layer and an amorphous silicon material layer on the underlying substrate 2, and performing phosphorus element doping and etching to form a passivation contact layer 6 on the second surface 12 of the underlying substrate 2, and depositing aluminum oxide on the doped conductive layer 3 to form a first passivation film layer 4, thereby forming the substrate 10 shown in FIG. 7.

[0070] In step (G), an anti-reflective coating layer 5 is formed on the first passivation film layer 4. As shown in Fig. 10, a side surface 13 of the base substrate 2 is flush with edges of the doped conductive layer 3, the first passivation film layer 4, and the anti-reflective coating layer 5 located on the same side as the side surface 13 in the normal direction of the side surface 13.

[0071] In step (H), the first structure is placed between the positioning protrusions 9 on the positioning boat 8 with the anti-reflective coating layer 5 facing the positioning boat 8 and spaced from the positioning boat 8, and a second passivation material is formed on the unshielded surface area of ​​the first structure. The first structure is a substrate 10 on which an anti-reflective coating layer is formed.

[0072] The relative positions of the positioning projections 9 and the side surfaces 13 of the base substrate 2 are adjusted, and then the first structure 11, a second passivation material is formed on the unshielded surface area of ​​the base substrate 2 to form a second passivation film layer 7 on the passivation contact layer 6. As shown in FIG. 11, the second passivation film layer 7 completely covers each side surface 13 of the base substrate 2, completely covers edges of the doped conductive layer 3, the first passivation film layer 4, and the anti-reflective coating layer 5 located on the same side as each side surface 13, and further covers a part of the anti-reflective coating layer 5 adjacent to the side surface 13 of the base substrate 2.

[0073] In step (I), electrodes are formed on the anti-reflection film layer 5 and the second passivation film layer 7, electricity is injected, and a test screening is performed.

[0074] In this embodiment, the adjustment of the gap between the substrate 10 and the positioning boat 8 can be performed, for example, by adjusting the positions of the positioning protrusions 9 on both sides of the substrate 10 in the altitude direction H of the positioning boat 8, as shown in Fig. 6. The positioning protrusions 9 can be moved downward in the altitude direction H of the positioning boat 8 according to the direction of the arrow shown in Fig. 6 to increase the gap between the substrate 10 and the positioning boat 8. Conversely, the gap can be decreased.

[0075] This embodiment further provides a photovoltaic module, which includes at least one cell string, which includes at least two of the above-mentioned solar cells 1, and each solar cell 1 is connected together by a series welding manner.

[0076] Exemplarily, the photovoltaic module further includes a sealing layer and a cover plate, the sealing layer is used to cover the surface of the battery string, and the cover plate is used to cover the surface of the sealing layer away from the battery string. The solar cells 1 are electrically connected in the form of a single or multi-cut cell to form a battery string, and the multiple battery strings are electrically connected in the form of series and / or parallel. The sealing layer may be an organic sealing film such as an ethylene-vinyl acetate copolymer film, a polyethylene octene rubber elastomer film, or a polyethylene terephthalate film. The cover plate may be a cover plate having a light transmission function, such as a glass cover plate, a plastic cover plate, etc.

[0077] This embodiment further provides a photovoltaic system, which includes the above-mentioned photovoltaic module. The configuration, function, working principle, etc. of the photovoltaic module and the solar cell have been described in detail above, so they will not be repeated here.

[0078] The technical features of the above embodiments can be combined in any manner, and for the sake of simplicity, not all possible combinations of the technical features in the above embodiments are described, but as long as the combinations of these technical features are not contradictory, they should all be considered within the scope described in this specification.

[0079] The above examples merely represent some embodiments of the present invention, and the description is relatively specific and detailed, but this should not be understood as a limitation on the scope of the claims of the invention. It should be noted that those skilled in the art can make some modifications and improvements without departing from the concept of the present invention, and all of them are within the scope of protection of the present invention. Therefore, the scope of protection of the patent of the present invention is based on the attached claims.

Claims

1. A solar cell comprising: an underlying substrate including a first surface and a second surface disposed opposite to each other and a plurality of side surfaces adjacent to the first surface and the second surface; a doped conductive layer and a first passivation film layer, which are stacked in order on the first surface and cover only the first surface; an anti-reflection film layer disposed on the first passivation film layer, the anti-reflection film layer covering the first surface so as to cover at least the first passivation film layer; a passivation contact layer disposed on the second surface; a second passivation film layer disposed on the passivation contact layer, the second passivation film layer covering the second surface so as to cover at least the passivation contact layer; Including, The second passivation film layer further covers at least a portion of each of the side surfaces. A solar cell characterized by:

2. a side surface of the base substrate is flush with edges of the doped conductive layer, the first passivation film layer, and the anti-reflection film layer that are located on the same side as the side surface in a normal direction of the side surface; The second passivation film layer has a partial structure on each side and completely covers at least each of the side surfaces; and completely covering at least the edges of the doped conductive layer, the first passivation film layer, and the anti-reflection film layer located on the same side as the side surfaces. The solar cell according to claim 1 .

3. the second passivation film layer further covers at least a portion of the first surface adjacent to each of the side surfaces; Alternatively, an edge of the second passivation film layer along the thickness direction of the base substrate is flush with an outer surface of the anti-reflection film layer along the thickness direction of the base substrate. The solar cell according to claim 2 .

4. a part of the second passivation film layer is laminated on an edge of the anti-reflection film layer on the first surface, the thickness of the laminated region of the second passivation film layer and the anti-reflection film layer from the passivation contact layer is greater than the thickness of a region of the central region of the solar cell where the anti-reflection film layer is not laminated, and the difference between the thicknesses is 5 nm to 1 μm; The solar cell according to claim 3 .

5. A method for manufacturing a solar cell, comprising the steps of: providing a substrate including: an underlying substrate including a first surface and a second surface disposed opposite to each other and a plurality of side surfaces adjacent to the first surface and the second surface; a doped conductive layer and a first passivation film layer disposed in sequence on the first surface and covering only the first surface; and a passivation contact layer disposed on the second surface; forming an anti-reflective coating layer on the first passivation film layer, the anti-reflective coating layer covering the first surface so as to cover at least the first passivation film layer; forming a second passivation film layer on the passivation contact layer, the second passivation film layer covering the second surface so as to completely cover the passivation contact layer; The second passivation film layer further covers at least a portion of each of the side surfaces. A method for producing a solar cell comprising the steps of:

6. a side surface of the base substrate is flush with edges of the doped conductive layer, the first passivation film layer, and the anti-reflection film layer that are located on the same side as the side surface in a normal direction of the side surface; forming a second passivation film layer on the passivation contact layer, a first structure, which is the substrate on which the anti-reflective coating layer is formed, is engaged and placed between positioning protrusions provided on a positioning boat in a state in which the anti-reflective coating layer faces a positioning boat, and a second passivation material is formed on an unshielded surface of the first structure; adjusting the relative positions of each positioning protrusion and the side surface of the base substrate, and then forming a second passivation material on the unshielded surface of the first structure to form a second passivation film layer on the passivation contact layer; the second passivation film layer completely covers at least each of the side surfaces of the base substrate, and completely covers at least edges of the doped conductive layer, the first passivation film layer, and the anti-reflective coating layer that are located on the same side as the each of the side surfaces; The method for producing a solar cell according to claim 5 .

7. when the anti-reflection film layer is bonded to the positioning boat, an edge of the formed second passivation film layer along a thickness direction of the base substrate is flush with an outer surface of the anti-reflection film layer along a thickness direction of the base substrate; the second passivation film layer formed with the anti-reflection film layer spaced apart from the positioning boat further covers at least a portion of an area adjacent to each of the side surfaces of the first surface; The method for producing a solar cell according to claim 6 .

8. The step of providing a substrate comprises: forming the doped conductive layer on a first surface of the base substrate; forming the passivation contact layer on a second surface of the underlying substrate; forming the first passivation layer on the doped conductive layer. The method for producing a solar cell according to any one of claims 5 to 7.

9. 1. A photovoltaic module comprising: at least one battery string; The battery string includes at least two solar cells according to any one of claims 1 to 4. A photovoltaic module comprising:

10. 1. A photovoltaic system comprising:

10. A photovoltaic module comprising the photovoltaic module of claim 9.

1. A photovoltaic system comprising:

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