A solar cell and photovoltaic module

Abstract

The present application discloses a solar cell and a photovoltaic module, wherein the solar cell comprises: a cell body, at least one side of which is provided with a plurality of spaced isolation protrusions, the refractive index of the isolation protrusions being less than the refractive index of the cell body. Furthermore, in the process of stacking the cells, the isolation protrusions are used to form isolation protection for the surface of the cell to prevent the surface of the cell from being scratched, and at the same time, by setting the refractive index of the plurality of isolation protrusions to be less than the refractive index of the cell body, a light trapping effect is formed on the surface of the cell, which helps to improve the absorption rate of the cell to light, thereby improving the conversion efficiency of the cell.

Description

Technical Field

[0001] The present application belongs to the field of photovoltaic technology, and specifically relates to a solar cell and a photovoltaic module. Background Art

[0002] In a back-contact cell, by placing both the PN junction and the metal electrode on the backlight side of the cell, the electrode is prevented from blocking the light-receiving side of the cell, which can maximize the use of incident light and reduce optical losses, thereby achieving the purpose of improving the conversion efficiency of the solar cell.

[0003] In the production process of back-contact cells, the cells usually need to be stacked and transported. In related technologies, in order to avoid scratches between cells, the entire front surface of the cell is usually covered with a film layer. However, after the entire front surface of the cell is covered with a film layer, the conversion efficiency of the cell and the photovoltaic module is adversely affected. Summary of the invention

[0004] The present application aims to provide a solar cell and a photovoltaic module, which can solve the problem in the related art that the conversion efficiency of the solar cell and the photovoltaic module is adversely affected after the entire front surface of the solar cell is covered with a film layer.

[0005] In order to solve the above technical problems, this application is implemented as follows:

[0006] In a first aspect, an embodiment of the present application proposes a solar cell, comprising: a cell body, at least one side of the cell body being provided with a plurality of isolation protrusions arranged at intervals, the refractive index of the isolation protrusions being smaller than the refractive index of the cell body.

[0007] Optionally, the battery cell body includes a light-receiving surface and a backlight surface opposite to each other, and the isolation protrusion is arranged on the light-receiving surface.

[0008] Optionally, a ratio of a refractive index of the isolation protrusion to a refractive index of the battery cell body is 0.8 to 0.95.

[0009] Optionally, the refractive index of the isolation protrusion is: 1.6 to 1.7;

[0010] And / or, the refractive index of the battery cell body is: 1.8 to 2;

[0011] And / or, the light transmittance of the isolation protrusion is greater than or equal to 85%.

[0012] Optionally, a surface of the isolation protrusion facing away from the battery cell body is a curved surface, and the curved surface protrudes in a direction away from the battery cell body.

[0013] Optionally, the curvature of the curved surface is greater than or equal to 0.05 μm -1.

[0014] Optionally, the side of the battery cell body provided with the isolation protrusion is the first side, and the height of the isolation protrusion along the direction perpendicular to the first side is H1; the cross-section perpendicular to the arrangement direction of the isolation protrusion is the second side, and the size of the isolation protrusion at the junction of the first side and the second side is L1, satisfying: H1 / L1≥0.1.

[0015] Optionally, a height H1 of the isolation protrusion along a direction perpendicular to the first surface is 5 μm to 40 μm;

[0016] And / or, a size L1 of the isolation protrusion at the boundary between the first surface and the second surface is 100 μm to 300 μm.

[0017] Optionally, a side of the battery cell body provided with the isolation protrusions is a first side, and a height of the isolation protrusions along a direction perpendicular to the first side is proportional to a distance between two adjacent isolation protrusions.

[0018] Optionally, a plurality of pyramid structures are provided on a surface of one side of the battery cell body on which the isolation protrusion is provided, and the isolation protrusion covers at least two of the pyramid structures;

[0019] And / or, a plurality of the isolation protrusions are arranged in an array.

[0020] Optionally, the material of the isolation protrusion is UV glue; and / or the Mohs hardness of the isolation protrusion is 2-7.

[0021] In a second aspect, an embodiment of the present application provides a photovoltaic module, comprising any of the solar cell sheets described above.

[0022] Optionally, the photovoltaic module further includes: an adhesive film layer, the side of the cell body provided with the isolation protrusion is the first side, the adhesive film layer is provided on the first side, the adhesive film layer covers the isolation protrusion, and the refractive index of the adhesive film layer is smaller than the refractive index of the isolation protrusion.

[0023] Optionally, the refractive index of the adhesive film layer is 1.40-1.5; and / or the light transmittance of the adhesive film layer is greater than 90%.

[0024] Optionally, the adhesive film layer includes a plurality of sub-film layers stacked in sequence, and the refractive index of the plurality of sub-film layers decreases from the first surface toward a direction away from the battery cell body.

[0025] Optionally, along a direction perpendicular to the first surface, a ratio of a height of the isolation protrusion to a height of the adhesive film layer is 20% to 45%.

[0026] Optionally, along a direction perpendicular to the first surface, a height of the isolation protrusion in the photovoltaic module is 2 μm to 37 μm; and / or a height of the adhesive film layer is 35 μm to 45 μm.

[0027] In an embodiment of the present application, a plurality of isolation protrusions arranged at intervals are provided on at least one side of the battery cell body so that during the battery cell stacking process, the isolation protrusions can be used to form isolation protection for the surface of the battery cell to prevent the surface of the battery cell from being scratched. At the same time, the refractive index of the plurality of isolation protrusions is set to be smaller than the refractive index of the battery cell body so as to form a light trapping effect on the surface of the battery cell, which helps to improve the battery cell's absorption rate of light, thereby improving the conversion efficiency of the battery cell.

[0028] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0030] Figure 1 is a schematic diagram of a solar cell according to an embodiment of the present application;

[0031] Figure 2 is a schematic diagram of a local structure when the isolation protrusion according to an embodiment of the present application is a strip-shaped protrusion;

[0032] Figure 3 is a structural diagram of an isolation protrusion under a 3D microscope according to an embodiment of the present application;

[0033] Figure 4 is a schematic diagram of a case where the isolation protrusions according to an embodiment of the present application are dot-shaped protrusions;

[0034] Figure 5 is a side view of the isolation protrusion according to an embodiment of the present application when the isolation protrusion is a dot-shaped protrusion;

[0035] Figure 6 is a schematic diagram of a photovoltaic assembly according to an embodiment of the present application;

[0036] Figure 7a is a schematic diagram of a processing flow of a solar cell according to an embodiment of the present application;

[0037] Figure 7b It is a schematic diagram of another processing flow of a solar cell according to an embodiment of the present application.

[0038] Reference numerals:

[0039] 100: battery cell body; 110: electrode; 120: pyramid structure; 200: isolation protrusion; 201: curved surface; 300: adhesive film layer. DETAILED DESCRIPTION

[0040] The embodiments of the present application will be described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and should not be construed as limitations on the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present application.

[0041] The term "first" or "second" in the specification and claims of this application may include one or more of the features explicitly or implicitly. In the description of this application, unless otherwise specified, "plurality" means two or more. In addition, "and / or" in the specification and claims means at least one of the connected objects, and the character " / " generally means that the objects connected before and after are in an "or" relationship.

[0042] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0043] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0044] The solar cell and photovoltaic module provided in the embodiments of the present application are described in detail below through specific embodiments and their application scenarios in conjunction with the accompanying drawings.

[0045] like Figure 1As shown, according to some embodiments of the present application, the solar cell comprises: a cell body 100 , at least one side of the cell body 100 is provided with a plurality of isolation protrusions 200 arranged at intervals, and the refractive index of the isolation protrusions 200 is smaller than the refractive index of the cell body 100 .

[0046] In the embodiment of the present application, a plurality of isolation protrusions 200 are arranged at intervals on at least one side of the battery cell body 100, so that during the battery cell stacking process, the isolation protrusions 200 can be used to form isolation protection for the surface of the battery cell to prevent the surface of the battery cell from being scratched. At the same time, the refractive index of the plurality of isolation protrusions 200 is set to be smaller than the refractive index of the battery cell body 100, so as to form a light trapping effect on the surface of the battery cell, which helps to improve the absorption rate of the battery cell to light, thereby improving the conversion efficiency of the battery cell.

[0047] It can be understood that the solar cell (hereinafter referred to as the cell) includes a cell body 100, which has a light-receiving surface and a backlight surface. The light-receiving surface is the side of the cell body 100 that receives incident light, and the backlight surface is the side of the cell body 100 that is away from the light-receiving surface.

[0048] Furthermore, a plurality of isolation protrusions 200 are arranged at intervals on at least one of the light-receiving surface and the backlight surface of the battery cell body 100. The isolation protrusions 200 protrude and extend from the surface of the battery cell body 100 in a direction away from the battery cell body 100, thereby forming an isolation and protection effect on the surface of the battery cell body 100.

[0049] For example, the cell in the embodiment of the present application is a back contact solar cell, and the electrodes 110 of the back contact solar cell are all arranged on the backlight surface, and a plurality of spaced isolation protrusions 200 can be arranged on the light receiving surface of the back contact solar cell. The following will be explained by taking the cell as a back contact solar cell as an example. When the cell is other types of cells, the mechanism of action can be implemented with reference to it, and the embodiment of the present application will not be repeated here.

[0050] It is understandable that in the process of preparing battery cells, a material box is usually used to store or transport multiple battery cells. When multiple battery cells are stacked, the light-receiving surface of one of the upper and lower battery cells will be opposite to the backlight surface of the other battery cell, making the light-receiving surface of one battery cell easily scratched by friction with the electrode 110 on the backlight surface of the other battery cell.

[0051] To this end, in an embodiment of the present application, a plurality of isolation protrusions 200 arranged at intervals are provided on the light-receiving surface of the battery cell, so that during the stacking process, the isolation protrusions 200 can be utilized to form an isolation support function between two adjacent battery cells, thereby providing isolation protection for the light-receiving surface of the battery cell and preventing the light-receiving surface of the battery cell from being scratched by the electrode 110 on the backlight surface of the adjacent battery cell.

[0052] At the same time, by setting the refractive index of the isolation protrusion 200 to be smaller than the refractive index of the battery cell body 100, as shown in FIG. Figure 1 As shown by the arrows in the figure, when the incident light is irradiated on the isolation protrusion 200, most of the light will pass through the isolation protrusion 200 and be absorbed by the battery cell, and a small part of the light will be repeatedly refracted or reflected between multiple isolation protrusions 200 and absorbed by the battery cell again, thereby forming a light trapping effect, which increases the battery cell's absorption rate of light and can improve the conversion efficiency of the battery cell.

[0053] In some embodiments, the isolation protrusion 200 can be made of materials such as UV glue, wherein the main component of the UV glue is preferably acrylic resin.

[0054] The transmittance of the isolation protrusion 200 can be set to be greater than or equal to 85%. For example, the transmittance of the isolation protrusion 200 is set to any value such as 85%, 87%, 90%, 93%, 95%, 98%, or a range between any two values.

[0055] In some embodiments, the isolation protrusions 200 include but are not limited to strip-shaped protrusions (such as Figure 2 and Figure 3 As shown), dot-like protrusions (such as Figure 4 and Figure 5 As shown), the strip-shaped protrusions may be a protrusion structure extending continuously along a preset direction, or a strip-shaped structure formed by a plurality of point-shaped protrusions arranged in sequence along the same direction. Of course, the isolation protrusions 200 may also be of other shapes and structures, which are not limited in the present application.

[0056] In some embodiments, the Mohs hardness of the isolation protrusion 200 is 2 to 7. Exemplarily, the Mohs hardness of the isolation protrusion 200 can be set to any value such as 2, 3, 4, 5, 6, 7, or a range between any two values.

[0057] It can be understood that a passivation layer, such as a silicon nitride layer, is usually formed on the surface of the battery cell body 100. The Mohs hardness of the silicon nitride layer ranges from 9 to 9.5. Therefore, by setting the Mohs hardness of the isolation protrusion 200 to 2 to 7, the Mohs hardness of the isolation protrusion 200 is lower than the Mohs hardness of the passivation layer on the surface of the battery cell body 100. Furthermore, when the battery cells are stacked, the isolation protrusion 200 can be used to support and isolate, while preventing the isolation protrusion 200 from scratching the surface of the battery cell body 100.

[0058] Optionally, a plurality of isolation protrusions 200 are arranged in an array on the cell surface to increase the distribution uniformity of the isolation protrusions 200 on the cell body 100 surface, thereby enhancing the protection of different areas of the cell surface and forming a uniform light trapping effect at different locations on the cell surface.

[0059] Optionally, the ratio of the refractive index of the isolation protrusion 200 to the refractive index of the cell body 100 is 0.8 to 0.95.

[0060] In the embodiment of the present application, the refractive index of the isolation protrusion 200 is set to be smaller than the refractive index of the battery cell body 100, and the ratio range of the refractive index of the isolation protrusion 200 to the refractive index of the battery cell body 100 is set to ensure that a light trapping effect can be formed on the surface of the battery cell body 100. In this way, the isolation protrusion 200 can be used to form an isolation and protection effect on the surface of the battery cell, and at the same time, the absorption rate of the battery cell to light can be improved, thereby improving the conversion efficiency of the battery cell.

[0061] Exemplarily, the ratio of the refractive index of the isolation protrusion 200 to the refractive index of the battery cell body 100 can be set to any value such as 0.8, 0.82, 0.85, 0.87, 0.9, 0.93, 0.95, or a range between any two values.

[0062] Optionally, the refractive index of the isolation protrusion 200 is 1.6-1.7.

[0063] In the embodiment of the present application, by setting the refractive index range of the isolation protrusion 200, the multiple isolation protrusions 200 on the surface of the battery cell can be used to isolate and protect the battery cell. At the same time, the multiple isolation protrusions 200 can be used to form a light trapping effect on the surface of the battery cell 100, thereby increasing the light absorption rate of the battery cell and improving the conversion efficiency of the battery cell.

[0064] Exemplarily, the refractive index of the isolation protrusion 200 can be set to any value such as 1.6, 1.61, 1.63, 1.65, 1.68, 1.7, etc., or a range between any two values.

[0065] Optionally, the refractive index of the cell body 100 is 1.8-2.

[0066] In the embodiment of the present application, the refractive index range of the cell body 100 is set to ensure that the refractive index of the cell body 100 is greater than the refractive index of the isolation protrusions 200, so that the multiple isolation protrusions 200 on the surface of the cell body 100 can form a light trapping effect, thereby increasing the light absorption rate of the cell and improving the conversion efficiency of the cell.

[0067] Exemplarily, the refractive index of the cell body 100 may be set to any value such as 1.8, 1.82, 1.85, 1.87, 1.9, 1.93, 1.95, 1.98, 2.0, or a range between any two values.

[0068] Alternatively, if Figure 1 As shown, the side surface of the isolation protrusion 200 facing away from the battery cell body 100 is a curved surface 201 , and the curved surface 201 protrudes from the surface of the battery cell body 100 toward a direction away from the battery cell body 100 .

[0069] In the embodiment of the present application, by setting the isolation protrusion 200 to have a curved surface 201 on the side facing away from the battery cell body 100, it is convenient for practical design and processing, and is also beneficial for forming a light trapping effect on the surface of the battery cell body 100, thereby improving the light absorption rate of the battery cell and improving the conversion efficiency of the battery cell.

[0070] For example, the curved surface 201 of the side of the isolation protrusion 200 facing away from the battery cell body 100 can be a curved surface structure such as an arc surface, an ellipsoidal surface, a parabolic surface, etc. Of course, it can also be set as a curved surface structure of other shapes, which can be flexibly set according to actual conditions, and the embodiment of the application does not limit this.

[0071] Optionally, the curvature of the curved surface 201 is greater than or equal to 0.05 μm. -1 .

[0072] In the embodiment of the present application, the curvature of the curved surface 201 of the side surface of the isolation protrusion 200 facing away from the battery cell body 100 is controlled to ensure that the side surface of the isolation protrusion 200 facing away from the battery cell body 100 has a certain curvature, which is conducive to forming a light trapping effect. At the same time, it can also ensure that the isolation protrusion 200 has a certain height to play an isolating and protective role on the surface of the battery cell body 100.

[0073] For example, the curvature of the curved surface 201 may be set to: 0.05 μm -1 , 0.08μm -1 , 0.1μm -1 , 0.5μm -1 , 1.0μm -1 , 2.0μm -1 , 5.0μm-1 Any number or a range between any two values.

[0074] Alternatively, if Figure 1 As shown, the side of the battery cell body 100 provided with the isolation protrusion 200 is the first side, the height of the isolation protrusion 200 in the direction perpendicular to the first side is H1, the cross section perpendicular to the arrangement direction of the isolation protrusion 200 is the second side, and the size of the isolation protrusion 200 at the junction of the first side and the second side is L1 (hereinafter referred to as width L1), satisfying: H1 / L1≥0.1. Preferably, 0.1≤H1 / L1≤0.5.

[0075] In the embodiment of the present application, by setting a reasonable height-to-width ratio of the isolation protrusion 200, it is possible to ensure that the isolation protrusion 200 has an isolating and protective effect on the surface of the battery cell, and to form a better light trapping effect on the surface of the battery cell, which helps to improve the conversion efficiency of the battery cell.

[0076] It is understandable that if the ratio of the height to the width of the isolation protrusion 200 is too small, that is, the height of the isolation protrusion 200 is relatively small and the width is relatively large, this will not only affect the isolation support function of the isolation protrusion 200, but also the corresponding morphology of the isolation protrusion 200 with a small height-to-width ratio will weaken the light trapping effect formed on the surface of the battery cell. If the ratio of the height to the width of the isolation protrusion 200 is too large, that is, the height of the isolation protrusion 200 is relatively large and the width is relatively small, this will reduce the structural strength of the isolation protrusion 200, not only inconvenient for actual processing, but also the isolation protrusion 200 is easily damaged, affecting the stability of the isolation protrusion 200.

[0077] For example, the ratio H1 / L1 of the height H1 of the isolation protrusion 200 to the width L1 of the isolation protrusion 200 may be set to any number such as 0.1, 0.15, 0.2, 0.25, 0.3, 0.4, 0.5, 0.6, 0.7, or a range between any two values.

[0078] It should be noted that the arrangement direction of the isolation protrusions is the extension direction of the projection of the isolation protrusions on the first surface. For example, the arrangement direction of the strip isolation protrusions is the length direction of the projection of the strip on the first surface. For another example, the arrangement direction of the hemispherical isolation protrusions is the radius direction of the projection of the hemispherical shape on the first surface. For another example, the arrangement direction of the semi-ellipsoidal isolation protrusions is the short radius direction or the long radius direction of the projection of the semi-ellipsoid shape on the first surface. Optionally, as Figure 1 and Figure 2 As shown, the height H1 of the isolation protrusion 200 along the direction perpendicular to the first surface is 5 μm to 40 μm.

[0079] In the embodiment of the present application, by setting the range of the height H1 of the isolation protrusion 200 along the direction perpendicular to the first surface, the isolation protrusion 200 can be ensured to have a certain height, and when the battery cells are stacked, the isolation protrusion 200 can be isolated and supported between two adjacent battery cells. At the same time, setting the isolation protrusion 200 of a certain height can ensure that an effective light trapping effect can be formed on the surface of the battery cell body 100 to improve the conversion efficiency of the battery cell.

[0080] Exemplarily, the height H1 of the isolation protrusion 200 along the direction perpendicular to the first surface can be set to any value such as 5μm, 8μm, 10μm, 15μm, 20μm, 25μm, 30μm, 35μm, 40μm, or a range between any two values.

[0081] It should be noted that the measurement method of the height H1 of the isolation protrusion 200 includes: measuring the straight-line distance from any point on the surface of the isolation protrusion 200 to the first surface along a direction perpendicular to the first surface, and taking the maximum value as the measured value of the height H1 of the isolation protrusion 200.

[0082] Alternatively, if Figure 1 and Figure 2 As shown, a size L1 of the isolation protrusion 200 at the junction of the first surface and the second surface is 100-300 μm.

[0083] In the embodiment of the present application, the isolation protrusion 200 is set to have a size L1 at the junction of the first surface and the second surface, so that the isolation protrusion 200 forms a certain coverage area on the surface of the battery cell, thereby being able to protect the surface of the battery cell. At the same time, if the width of the isolation protrusion 200 is too large, the aspect ratio of the isolation protrusion 200 will be small, and the corresponding morphology will weaken the light trapping effect formed on the surface of the battery cell body 100.

[0084] Exemplarily, the dimension L1 of the isolation protrusion 200 at the junction of the first surface and the second surface can be set to any value such as 100 μm, 120 μm, 150 μm, 170 μm, 200 μm, 230 μm, 250 μm, 280 μm, 300 μm, or a range between any two values.

[0085] In some embodiments, the height of the isolation protrusion 200 is proportional to the spacing between two adjacent isolation protrusions 200. For example, the spacing between two adjacent isolation protrusions 200 is 10-12 mm, and correspondingly, the height of the isolation protrusion 200 is set to 30 μm; or, the spacing between two adjacent isolation protrusions 200 is 3-5 mm, and correspondingly, the height of the isolation protrusion 200 is set to 10 μm.

[0086] Alternatively, if Figure 6 As shown, a plurality of pyramid structures 120 are provided on a surface of the battery cell body 100 on one side where the isolation protrusion 200 is provided, and the isolation protrusion 200 covers at least two pyramid structures 120 .

[0087] In the embodiment of the present application, a plurality of pyramid structures 120 are provided on the surface of one side of the cell body 100 where the isolation protrusion 200 is provided, so that the isolation protrusion 200 covers at least two pyramid structures 120, so that the synergistic effect of the plurality of isolation protrusions 200 and the plurality of pyramid structures 120 can be utilized to enhance the light trapping effect formed on the surface of the cell body 100, thereby further improving the conversion efficiency of the cell.

[0088] It is understandable that in the cell preparation process, a velvet structure can be formed on the light-receiving surface and / or the backlight surface of the silicon substrate by a velvet process, and then an anti-reflection layer or a passivation layer is formed on the velvet structure, and a cell body 100 with a plurality of pyramid structures 120 formed on the surface can be obtained. Then, a plurality of isolation protrusions 200 are formed on the anti-reflection layer or the passivation layer, and the isolation protrusions 200 cover at least two pyramid structures 120. Among them, the velvet process in the embodiment of the present application can be performed with reference to the relevant technology, and the embodiment of the present application will not be repeated here.

[0089] In some embodiments. Figure 7a As shown, the preparation process of the solar cell in the present application may include:

[0090] S1. Provide a cell body 100, wherein the cell body 100 includes a light-receiving surface and a backlight surface opposite to each other;

[0091] S2, printing grid lines on the backlight surface of the cell body 100, and sending it into a sintering furnace for sintering;

[0092] S3, forming an isolation protrusion 200 on the light-receiving surface of the battery cell body 100;

[0093] S4, processing the battery cell body 100 using a light injection or curing furnace;

[0094] S5. Perform performance test on the battery cells, sort and stack them.

[0095] It is understandable that compared with the traditional battery cell production process, after completing the formation inspection of the battery cells, the battery cells need to be isolated with isolation paper and sorted and stacked. During the operation, it is necessary to add steps such as laying and extracting the isolation paper. The operation process is cumbersome and the production cost is high.

[0096] In the embodiment of the present application, after the gate line paste is printed and sintered at high temperature, an isolation protrusion 200 is formed on the light-receiving surface of the cell so that the isolation protrusion 200 can be used to isolate and protect the cell in subsequent processes, thereby simplifying the operation process and reducing production costs.

[0097] In other embodiments, Figure 7b As shown, after the sintering operation in the sintering furnace is completed in step S2, the cell body 100 can be processed by a light injection or curing furnace, and then an isolation protrusion 200 is formed on the light-receiving surface of the cell body 100. In this way, the requirements for the high temperature resistance of the isolation protrusion 200 can be reduced.

[0098] In some embodiments, step S3 of forming the isolation protrusion 200 on the light-receiving surface of the battery cell body 100 in the above embodiment may include:

[0099] S31, using a preset glue material to form a plurality of preset glue points on the light-receiving surface of the battery cell body 100;

[0100] S32 , curing the preset glue points to obtain a plurality of isolation protrusions 200 arranged at intervals, wherein the refractive index of the isolation protrusions 200 is smaller than the refractive index of the battery cell body 100 .

[0101] Specifically, the isolation protrusions 200 can be formed on the surface of the battery cell body 100 by screen printing. The screen used is provided with a plurality of meshes, which form a preset pattern, and the preset pattern matches the arrangement structure of the isolation protrusions 200 to be printed, the mesh number ranges from 200 to 450 meshes, and the thickness of the screen is 25 to 40 μm.

[0102] Of course, a number of preset glue points may be formed on the light-receiving surface of the battery cell body 100 by dispensing glue or coating, and may be flexibly arranged according to actual conditions, and the embodiment of the present application does not limit this.

[0103] In some other embodiments, the viscosity of the preset adhesive is set to 7000-20000 cps; the high temperature resistance of the formed isolation protrusion 200 is greater than or equal to 300°C.

[0104] Alternatively, if Figure 6 As shown, an embodiment of the present application further provides a photovoltaic assembly, comprising the solar cell in the above embodiment.

[0105] In the embodiment of the present application, a plurality of isolation protrusions 200 are arranged at intervals on at least one side of the battery cell body 100, so that during the battery cell stacking process, the isolation protrusions 200 can be used to form isolation protection for the surface of the battery cell to prevent the surface of the battery cell from being scratched. At the same time, the refractive index of the plurality of isolation protrusions 200 is set to be smaller than the refractive index of the battery cell body 100, so as to form a light trapping effect on the surface of the battery cell, which helps to improve the absorption rate of the battery cell to light, thereby improving the conversion efficiency of the battery cell.

[0106] Alternatively, if Figure 6 As shown, the photovoltaic module also includes: a film layer 300, and the side of the cell body 100 provided with the isolation protrusion 200 is the first side, and the film layer 300 is provided on the first side, the film layer 300 covers the isolation protrusion 200, and the refractive index of the film layer 300 is less than the refractive index of the isolation protrusion 200.

[0107] In the embodiment of the present application, a film layer 300 is provided on one side of the cell body 100 provided with the isolation protrusion 200, so that the film layer 300 covers the isolation protrusion 200, and the isolation protrusion 200 is embedded in the film layer 300, and the incident light passes through the film layer 300 and the isolation protrusion 200 in sequence before entering the cell body 100. Furthermore, by setting the refractive index of the film layer 300, the isolation protrusion 200 and the cell body 100 to increase in sequence, it is convenient to form a light trapping effect at different refractive index interfaces to increase the light absorption rate of the cell, thereby improving the conversion efficiency of the photovoltaic module.

[0108] In some embodiments, the adhesive film layer 300 can be made of a light-transmitting material such as POE or EVA to provide packaging and protection for the battery cells. The light transmittance of the adhesive film layer 300 is greater than or equal to 90%. For example, the light transmittance of the adhesive film layer 300 can be set to any value such as 90%, 92%, 93%, 95%, or 98%.

[0109] It should be noted that, as long as the refractive index of the adhesive film layer 300 is lower than the refractive index of the isolation protrusion 200 , the specific materials of the adhesive film layer 300 and the isolation protrusion 200 can be flexibly selected according to actual needs, and the embodiment of the present application does not limit this.

[0110] Optionally, the refractive index of the adhesive film layer 300 is 1.4-1.5.

[0111] In the present application example, the refractive index range of the adhesive film layer 300 is set to ensure that the refractive index of the adhesive film layer 300 is smaller than the refractive index of the isolation protrusion 200, so as to form a light trapping effect between the adhesive film layer 300 and the isolation protrusion 200, thereby improving the conversion efficiency of the photovoltaic module.

[0112] Exemplarily, the refractive index of the adhesive film layer 300 may be set to any value such as 1.4, 1.42, 1.45, 1.47, 1.48, 1.5, or a range between any two values.

[0113] Optionally, the adhesive film layer 300 includes a plurality of sub-film layers stacked in sequence, and the refractive index of the plurality of sub-film layers decreases from the first surface toward a direction away from the battery cell body 100 .

[0114] In the embodiment of the present application, the adhesive film layer 300 includes a plurality of sub-film layers stacked in sequence, and the refractive index of the plurality of sub-film layers decreases in the direction away from the cell body 100. This is beneficial for light to pass through the adhesive film layer 300 and enter the interior of the photovoltaic module, thereby reducing reflection of light at different interfaces, thereby increasing the light absorption rate of the cell and improving the conversion efficiency of the photovoltaic module.

[0115] Among them, the multiple sub-film layers can be made of different materials, for example, as long as the refractive index of each sub-film layer decreases in the direction away from the battery cell body 100, and the embodiment of the present application is not limited here.

[0116] Alternatively, if Figure 6 As shown, along the direction perpendicular to the first surface, the ratio H11 / H2 of the height H11 of the isolation protrusion 200 to the height H2 of the adhesive film layer 300 is 20% to 45%.

[0117] It is understandable that in practical applications, cells are usually prepared first, and then photovoltaic modules are prepared from the cells. If the height difference between the adhesive film layer 300 and the isolation protrusion 200 is too small, that is, when preparing photovoltaic modules from the cells, the adhesive film layer 300 covering the cells is too thin, the adhesive film layer 300 cannot play an effective deformation buffering role during lamination, which can easily cause the cells to be crushed. If the height difference between the adhesive film layer 300 and the isolation protrusion 200 is too large, that is, the adhesive film layer 300 covering the cells is too thick, it will not only affect the transmission of light, but also increase the production cost of the adhesive film layer 300.

[0118] Therefore, in the embodiment of the present application, a reasonable value range of the height ratio of the isolation protrusion 200 and the film layer 300 is set, so that during the processing, the film layer 300 can be used to provide effective buffering protection for the battery cell while also taking the production cost into account. In addition, a better light trapping effect can be formed between the film layer 300 and the isolation protrusion 200.

[0119] Exemplarily, the height ratio H11 / H2 of the isolation protrusion 200 and the film layer 300 can be set to any value such as 20%, 22%, 25%, 28%, 30%, 35%, 40%, 43%, 45%, or a range between any two values.

[0120] Optionally, along a direction perpendicular to the first surface, a height of the isolation protrusion 200 in the photovoltaic module is 2 μm to 37 μm.

[0121] Exemplarily, the height of the isolation protrusion 200 in the photovoltaic module can be set to any value such as 2 μm, 5 μm, 8 μm, 10 μm, 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 37 μm, or a range between any two values.

[0122] Optionally, along a direction perpendicular to the first surface, a height of the adhesive film layer 300 is 35 μm to 45 μm.

[0123] Exemplarily, the height of the adhesive film layer 300 can be set to any value such as 35 μm, 36 μm, 38 μm, 40 μm, 41 μm, 43 μm, 45 μm, or a range between any two values.

[0124] In the embodiment of the present application, by setting a reasonable value range of the height H11 of the isolation protrusion 200 and the height H2 of the film layer 300 in the photovoltaic module, it can not only effectively protect the battery cell, but also improve the light absorption rate of the battery cell.

[0125] It should be noted that the height H11 of the isolation protrusion 200 on the surface of the cell body 100 in the photovoltaic module and the height H1 of the isolation protrusion 200 on the surface of the cell body 100 in the cell may be equal or unequal. Since lamination is required in the process of preparing photovoltaic modules from cells, the height of the isolation protrusion 200 on the surface of the cell body 100 will change. After the lamination process, the height of the isolation protrusion 200 will decrease, that is, the height value of H11 is lower than the height value of H1.

[0126] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0127] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present application, and that the scope of the present application is defined by the claims and their equivalents.

Claims

1. A solar cell, characterized in that: include: A cell body, the cell body comprising a light-receiving surface and a backlight surface opposite to each other, the light-receiving surface being provided with a plurality of spaced-apart isolation protrusions, the isolation protrusions being used to isolate and protect the surface of the cell; the refractive index of the isolation protrusions being less than the refractive index of the cell body; A plurality of pyramid structures are arranged on a surface of one side of the battery cell body where the isolation protrusion is arranged, and the isolation protrusion covers at least two of the pyramid structures.

2. The solar cell according to claim 1, characterized in that: The ratio of the refractive index of the isolation protrusion to the refractive index of the battery cell body is 0.8-0.

95.

3. The solar cell according to claim 2, characterized in that: The refractive index of the isolation protrusion is: 1.6~1.7; And / or, the refractive index of the cell body is: 1.8-2; And / or, the light transmittance of the isolation protrusion is greater than or equal to 85%.

4. The solar cell according to claim 1, characterized in that: A surface of the isolation protrusion facing away from the battery cell body is a curved surface, and the curved surface protrudes in a direction away from the battery cell body.

5. The solar cell according to claim 4, characterized in that: The curvature of the curved surface is greater than or equal to 0.05 μm -1 .

6. The solar cell according to claim 1, characterized in that: The side of the battery cell body provided with the isolation protrusion is a first side, and the height of the isolation protrusion along a direction perpendicular to the first side is H1; The cross section perpendicular to the arrangement direction of the isolation protrusions is the second surface, and the size of the isolation protrusion at the junction of the first surface and the second surface is L1, satisfying: H1 / L1≥0.

1.

7. The solar cell according to claim 6, characterized in that: The height H1 of the isolation protrusion along the direction perpendicular to the first surface is 5 μm to 40 μm; And / or, a size L1 of the isolation protrusion at the junction of the first surface and the second surface is 100 μm to 300 μm.

8. The solar cell according to claim 1, characterized in that: The side of the battery cell body provided with the isolation protrusions is a first side, and the height of the isolation protrusions along a direction perpendicular to the first side is proportional to the distance between two adjacent isolation protrusions.

9. The solar cell according to claim 1, characterized in that: A plurality of the isolation protrusions are arranged in an array.

10. The solar cell according to claim 1, characterized in that: The material of the isolation protrusion is UV glue; and / or the Mohs hardness of the isolation protrusion is 2-7.

11. A photovoltaic module, characterized in that: include: A solar cell according to any one of claims 1 to 10.

12. The photovoltaic module according to claim 11, characterized in that: The photovoltaic module further includes: an adhesive film layer, the side of the cell body provided with the isolation protrusion is the first side, the adhesive film layer is provided on the first side, the adhesive film layer covers the isolation protrusion, and the refractive index of the adhesive film layer is smaller than the refractive index of the isolation protrusion.

13. The photovoltaic module according to claim 12, characterized in that: The refractive index of the adhesive film layer is: 1.40-1.5; and / or the light transmittance of the adhesive film layer is greater than 90%.

14. The photovoltaic module according to claim 12, characterized in that: The adhesive film layer includes a plurality of sub-film layers stacked in sequence, and the refractive index of the plurality of sub-film layers decreases from the first surface toward a direction away from the battery cell body.

15. The photovoltaic module according to claim 12, characterized in that: Along a direction perpendicular to the first surface, a ratio of a height of the isolation protrusion to a height of the adhesive film layer is 20% to 45%.

16. The photovoltaic module according to claim 15, characterized in that: Along a direction perpendicular to the first surface, the height of the isolation protrusion in the photovoltaic module is 2 μm to 37 μm; and / or the height of the adhesive film layer is 35 μm to 45 μm.

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