A BIPV module based on crystalline silicon heterojunction solar cells

Abstract

This utility model discloses a BIPV module based on crystalline silicon heterojunction solar cells, including a light-transmitting first support plate group, a battery module, and a light-transmitting or opaque second support plate group. The battery module includes multiple battery strings arranged side by side and parallel to each other. Each battery string has an insulating layer on its edge wall near the adjacent battery string. The first support plate group, the battery module, and the second support plate group are stacked in sequence. This design can flexibly adjust the spacing between battery strings and the module size, improve photovoltaic conversion efficiency, and is flexible and reliable in use.

Description

Technical Field

[0001] This utility model relates to the field of solar cell equipment technology, and in particular to a BIPV module based on crystalline silicon heterojunction cells. Background Technology

[0002] With the advancement of the "dual carbon" goals, the demand for renewable energy in the building sector is increasing. Building integrated photovoltaics (BIPV), as an important way to achieve building energy conservation and low carbon emissions, has broad market potential.

[0003] Traditional BIPV modules typically use thin-film solar cells as photovoltaic conversion chips, such as cadmium telluride (CdTe), copper indium gallium selenide (CIGS), and perovskite. However, thin-film solar cells have low photoelectric conversion efficiency. Even perovskite thin-film solar cells currently have a commercially available chip efficiency of approximately 16-19%, which is still 4-7% lower than that of crystalline silicon solar cells. Therefore, BIPV modules based on crystalline silicon heterojunction solar cells have high commercial value, especially in applications where light transmittance requirements are not high. In these applications, BIPV modules based on crystalline silicon heterojunction solar cells generally offer better cost-effectiveness than thin-film BIPV modules. Furthermore, crystalline silicon heterojunction solar cells possess the dual characteristics of both crystalline silicon and thin-film solar cells, offering advantages such as excellent low-light performance, low temperature coefficient, and high conversion efficiency.

[0004] However, existing crystalline silicon heterojunction solar cells also have drawbacks. For example, the size of crystalline silicon heterojunction solar cells is basically fixed. To match the diverse sizes of BIPV modules, the only way to assemble BIPV modules of the required size is usually by laser-cutting the solar cells. However, cutting crystalline silicon solar cells, especially crystalline silicon heterojunction solar cells, leads to significant efficiency losses. Furthermore, with the thinning of silicon wafers, cutting is prone to defects such as wafer cracking. Some manufacturers have considered changing the overall size of BIPV modules by adjusting the spacing between multiple cell strings within the module. However, because sufficient insulation distance must be reserved between adjacent cell strings to prevent short circuits during assembly and use, size adjustments are still significantly limited. Utility Model Content

[0005] This invention aims to solve at least one of the technical problems existing in the prior art. To this end, this invention proposes a BIPV module based on crystalline silicon heterojunction cells, which can adaptively adjust the spacing between cell strings and the module size, thereby improving photovoltaic conversion efficiency and offering flexible and reliable use.

[0006] A BIPV module based on a crystalline silicon heterojunction solar cell according to a first aspect embodiment of the present invention includes: a light-transmitting first support plate group; a battery assembly including multiple battery strings arranged side by side and parallel to each other, wherein an insulating layer is provided on the edge wall of each battery string close to an adjacent battery string; and a light-transmitting or opaque second support plate group, wherein the first support plate group, the battery assembly, and the second support plate group are stacked in sequence.

[0007] A BIPV module based on a crystalline silicon heterojunction solar cell according to an embodiment of the present invention has at least the following beneficial effects:

[0008] This invention relates to a BIPV module based on crystalline silicon heterojunction cells. The module uses strings of crystalline silicon heterojunction cells to capture light energy and convert it into electrical energy, resulting in higher photoelectric conversion efficiency. An insulating layer is provided between the edge walls of adjacent strings, allowing for flexible adjustment of the spacing between them. Even when adjacent strings are close together, the insulating layer prevents short circuits. Therefore, the spacing between strings and the module size can be adjusted flexibly, improving photovoltaic conversion efficiency and offering flexible and reliable operation.

[0009] According to some embodiments of the present invention, the insulating layer covers the sidewalls of the battery string and at least the edge of the upper or lower wall of the battery string, and the insulating layer is located between the sidewalls of two adjacent battery strings.

[0010] According to some embodiments of the present invention, the edges of two adjacent battery strings are stacked on each other, and the insulating layer is located between the lower wall of one battery string and the upper wall of the other battery string.

[0011] According to some embodiments of the present invention, the insulating layer includes ultraviolet-curable adhesive, thermosetting adhesive, or aluminum oxide film.

[0012] According to some embodiments of the present invention, the first support plate assembly includes a light-transmitting first panel and an elastic first adhesive film, wherein the first panel, the first adhesive film and the battery assembly are stacked in sequence.

[0013] According to some embodiments of the present invention, the second support plate assembly includes a light-transmitting or opaque second panel and an elastic second adhesive film, wherein the second panel, the second adhesive film and the battery assembly are stacked in sequence.

[0014] According to some embodiments of the present invention, the first adhesive film and the second adhesive film are polyolefin colloids, ethylene vinyl acetate copolymer colloids, and polyethylene foam.

[0015] According to some embodiments of the present invention, the battery string includes multiple crystalline silicon heterojunction cells, which are connected in series and arranged along the length of the battery string, and adjacent cells are electrically connected by conductive wires.

[0016] According to some embodiments of the present invention, between two adjacent battery strings, the ends of one battery string and the ends of the other battery string located at the same end have opposite polarities and are connected by conductive wires so that the two battery strings are connected in series.

[0017] According to some embodiments of the present invention, the thickness of the insulating layer ranges from 1 to 10 μm.

[0018] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0019] The above and / or additional aspects and advantages of this utility model will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0020] Figure 1 This is a top view of one embodiment of the BIPV module based on crystalline silicon heterojunction solar cells of this utility model;

[0021] Figure 2 This is a partially enlarged view of the battery string in one embodiment of the BIPV module based on crystalline silicon heterojunction solar cells of this utility model.

[0022] Figure 3 This is a cross-sectional view of one embodiment of the BIPV module based on crystalline silicon heterojunction solar cells of this utility model;

[0023] Figure 4 This is a cross-sectional view of another embodiment of the BIPV module based on crystalline silicon heterojunction solar cells of this utility model.

[0024] Figure label:

[0025] First support plate assembly 100; first panel 110; first adhesive film 120; battery assembly 200; battery string 210; battery cell 220; second support plate assembly 300; second panel 310; second adhesive film 320; insulation layer 400. Detailed Implementation

[0026] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0027] In the description of this utility model, it should be understood that the directional descriptions, such as the terms "up," "down," "front," "back," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," indicate the directional or positional relationship based on the directional or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0028] In the description of this utility model, "several" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. If "first" or "second" is used in the description, it is only for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0029] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0030] like Figures 1 to 4 As shown, a BIPV module based on a crystalline silicon heterojunction solar cell according to a first aspect embodiment of the present invention includes a light-transmitting first support plate group 100, a battery assembly 200, and a light-transmitting or opaque second support plate group 300. The battery assembly 200 includes multiple battery strings 210, which are arranged side by side and parallel to each other. An insulating layer 400 is provided between the edge walls of the battery strings 210 and adjacent battery strings 210. The first support plate group 100, the battery assembly 200, and the second support plate group 300 are stacked in sequence.

[0031] The battery string 210 includes multiple silicon heterojunction cells 220, which are connected in series and arranged along the length of the battery string 210. Adjacent cells 220 are electrically connected by conductive wires.

[0032] A crystalline silicon heterojunction solar cell 220 typically includes, from top to bottom, a front contact electrode, a TCO, an n-type doped amorphous silicon layer (n-a-Si:H), an intrinsic amorphous silicon layer (i-a-Si:H), a crystalline silicon substrate, an intrinsic amorphous silicon layer (i-a-Si:H), a p-type doped amorphous silicon layer (p-a-Si:H), a TCO, and a back contact electrode, wherein the back contact electrode can be set as a positive electrode, and the front contact electrode can be set as a negative electrode.

[0033] Solar cell 220 is typically rectangular, such as Figure 2 As shown, in the same battery string 210, between two adjacent battery cells 220, the lower edge of the upper battery cell 220 and the upper edge of the lower battery cell 220 are close to each other and are electrically connected by conductive wires. In two adjacent battery strings 210, the side of one battery cell 220 is close to the side of the other battery cell 220 and is isolated from each other by an insulating layer 400.

[0034] In some embodiments of this utility model, such as Figure 1 As shown, between two adjacent battery strings 210, the ends of one battery string 210 and the ends of the other battery string 210 located at the same end have opposite polarities and are connected by conductive wires so that the two battery strings 210 are connected in series.

[0035] In a BIPV module, multiple battery strings 210 are connected in series. To shorten the length of the conductive wires connecting adjacent battery strings 210, the polarities of the two battery strings 210 at the same end are reversed. For example, at the beginning, the beginning of the first battery string 210 is the positive terminal, and the beginning of the second battery string 210 is the negative terminal. The positive terminal of the first battery string 210 is connected to the negative terminal of the second battery string 210 through the conductive wire. At the end, the end of the second battery string 210 is the positive terminal, and the end of the third battery string 210 is the negative terminal. The positive terminal of the second battery string 210 is connected to the negative terminal of the third battery string 210 through the conductive wire.

[0036] This utility model is a BIPV module based on crystalline silicon heterojunction cells. It uses a string of crystalline silicon heterojunction cells 210 to capture light energy and convert it into electrical energy, resulting in higher photoelectric conversion efficiency. An insulating layer 400 is provided between the edge walls of two adjacent strings of cells 210. This allows for arbitrary adjustment of the spacing between two adjacent strings of cells 210. Even if two adjacent strings of cells 210 are close together, short circuits are not likely to occur due to the isolation provided by the insulating layer 400. Therefore, the spacing between the strings of cells 210 and the module size can be adjusted flexibly to improve the photovoltaic conversion efficiency, making it flexible and reliable in use.

[0037] In some embodiments of this utility model, such as Figure 2 , 3 As shown, the insulating layer 400 covers the side wall of the battery string 210 and at least covers the edge of the upper or lower wall of the battery string 210, and the insulating layer 400 is located between the side wall of two adjacent battery strings 210.

[0038] The insulating layer 400 may affect the ability of the surface of the solar cell 220 to absorb light, thus reducing the photoelectric conversion efficiency. Therefore, this design only covers the edge of the solar cell 220 near the adjacent solar cell string 210 with the insulating layer 400, and does not cover the entire surface of the solar cell 220. In traditional BIPV modules composed of crystalline silicon heterojunction solar cells, a safety distance of at least 1 mm is required between solar cell strings 210 to avoid inter-string short circuits. However, the thickness of the insulating layer 400 in this design can be controlled within the range of 1-10 μm, and there is no need to reserve a safety distance, or the distance between solar cell strings 210 can be adjusted according to the actual size requirements.

[0039] In some embodiments of this utility model, such as Figure 4 As shown, the edges of two adjacent battery strings 210 are stacked on top of each other, and the insulating layer 400 is located between the lower wall of one battery string 210 and the upper wall of the other battery string 220.

[0040] Adjacent battery strings 210 can be placed close together, and the width of the stacking position can be adjusted according to the actual size required by the BIPV module. Although the photoelectric conversion efficiency of a single battery cell 220 is affected by the edge being covered by the insulating layer 400, the overall BIPV module has a larger number of cells, thus improving the photoelectric conversion efficiency.

[0041] Specifically, the insulating layer 400 can be applied to the battery cell 220 by means of screen printing, inkjet printing, automated film application, vacuum coating, etc. The insulating layer 400 includes ultraviolet curable adhesive, thermosetting adhesive, or aluminum oxide film.

[0042] In some embodiments of this utility model, the first support plate assembly 100 includes a light-transmitting first panel 110 and an elastic first adhesive film 120, wherein the first panel 110, the first adhesive film 120 and the battery assembly 200 are stacked in sequence.

[0043] The first adhesive film 120 has a certain elasticity. Since the surface of the battery cell 220 is covered with an insulating layer 400, adding the first adhesive film 120 between the first panel 110 and the battery cell 220 can improve the adhesion performance. At the same time, rigid pressure will not be generated at the location where the insulating layer 400 is set or at the location where the battery cells 220 are stacked, so as not to cause damage to the first panel 110 or the battery cell 220. Specifically, the first panel 110 can be single-coated or double-coated patterned glass, and can be semi-tempered or fully tempered.

[0044] In some embodiments of this utility model, the second support plate assembly 300 includes a light-transmitting or light-opaque second panel 310 and an elastic second adhesive film 320, wherein the second panel 310, the second adhesive film 320 and the battery assembly 200 are stacked in sequence.

[0045] Similarly, the second adhesive film 320 has a certain elasticity. Since the surface of the battery cell 220 is covered with the insulating layer 400, adding the second adhesive film 320 between the second panel 310 and the battery cell 220 can improve the adhesion performance. At the same time, no rigid pressure will be generated at the location where the insulating layer 400 is set, which will cause damage to the second panel 310 or the battery cell 220. Specifically, the second panel 310 can be float glass, which can be semi-tempered or fully tempered, or other opaque substrates such as KPK or TPT.

[0046] In some embodiments of this utility model, the first adhesive film 120 and the second adhesive film 320 are polyolefin colloids, ethylene vinyl acetate copolymer colloids, and polyethylene foam.

[0047] In some embodiments of this utility model, the thickness of the first panel 110 can be 2.0mm or 3.2mm, specifically, it can be 2.0mm. The basis weight of the first adhesive film 120 and the second adhesive film 320 can both be 380-420g / ㎡, specifically 380g / ㎡. The thickness of the second panel 310 is 2.0mm or 3.2mm, specifically, it can be 2.0mm.

[0048] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0049] Although embodiments of the present invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A BIPV module based on crystalline silicon heterojunction solar cells, characterized in that, include: The first support plate assembly that allows light to pass through; A battery assembly includes multiple battery strings arranged side by side and parallel to each other, wherein each battery string has an insulating layer on its edge wall near an adjacent battery string; A second support plate group that is either light-transmitting or opaque, wherein the first support plate group, the battery assembly, and the second support plate group are stacked in sequence.

2. A BIPV module based on a crystalline silicon heterojunction solar cell according to claim 1, characterized in that: The insulating layer covers the sidewalls of the battery string and at least the edges of the upper or lower wall of the battery string, and the insulating layer is located between the sidewalls of two adjacent battery strings.

3. A BIPV module based on a crystalline silicon heterojunction solar cell according to claim 1, characterized in that: The edges of two adjacent battery strings are stacked on top of each other, and the insulating layer is located between the lower wall of one battery string and the upper wall of the other battery string.

4. A BIPV module based on a crystalline silicon heterojunction solar cell according to claim 1, characterized in that: The insulating layer includes ultraviolet-curable adhesive, thermosetting adhesive, or aluminum oxide film.

5. A BIPV module based on a crystalline silicon heterojunction solar cell according to claim 1, characterized in that: The first support plate assembly includes a light-transmitting first panel and an elastic first adhesive film, with the first panel, the first adhesive film, and the battery assembly stacked in sequence.

6. A BIPV module based on a crystalline silicon heterojunction solar cell according to claim 5, characterized in that: The second support plate assembly includes a light-transmitting or opaque second panel and an elastic second adhesive film, wherein the second panel, the second adhesive film, and the battery assembly are stacked in sequence.

7. A BIPV module based on a crystalline silicon heterojunction solar cell according to claim 6, characterized in that: The first and second adhesive films are polyolefin colloids, ethylene-vinyl acetate copolymer colloids, or polyethylene foam.

8. A BIPV module based on a crystalline silicon heterojunction solar cell according to claim 1, characterized in that: The battery string includes multiple crystalline silicon heterojunction cells, which are connected in series and arranged along the length of the battery string. Adjacent cells are electrically connected by conductive wires.

9. A BIPV module based on a crystalline silicon heterojunction solar cell according to claim 8, characterized in that: Between two adjacent battery strings, the ends of one battery string and the other battery string located at the same end have opposite polarities and are connected by conductive wires so that the two battery strings are connected in series.

10. A BIPV module based on a crystalline silicon heterojunction solar cell according to claim 1, characterized in that: The thickness of the insulating layer ranges from 1 to 10 μm.

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