Conductive backsheet and cell assembly for mechanically stacked solar cells with double-sided light reception

Abstract

This application applies to the field of solar cell technology and provides a conductive backsheet and cell assembly for a mechanically stacked solar cell with double-sided light exposure. The conductive backsheet for a mechanically stacked solar cell with double-sided light exposure is used to connect a first solar cell and a second solar cell in a stacked arrangement. The backsheet includes a substrate, a first conductive layer, and a second conductive layer. The substrate has a first side facing the first solar cell and a second side facing the second solar cell. The first conductive layer is at least partially exposed from the first side of the substrate and is used to connect to the electrodes of the first solar cell. The second conductive layer is at least partially exposed from the second side of the substrate and is used to connect to the electrodes of the second solar cell. In this way, the first and second solar cells in a stacked arrangement can be packaged simultaneously.

Description

Technical Field

[0001] The present application belongs to the technical field of solar cells, and in particular relates to a conductive backplane and a cell assembly for a mechanically laminated solar cell with double-sided light reception. Background Art

[0002] In related technologies, conductive backsheets typically consist of a polymer composite insulation layer, a metal foil, a polymer backsheet, and an encapsulation layer stacked in this order. However, conductive backsheets are typically designed to receive light from a single side and can only encapsulate solar cells on a single side. Therefore, designing a conductive backsheet to encapsulate mechanically stacked solar cells with dual-sided light reception into modules has become a pressing issue. Summary of the Invention

[0003] The present application provides a conductive backplane and a cell assembly for a double-sided light-receiving mechanical stacked solar cell, aiming to solve the problem of how to design a conductive backplane to encapsulate the double-sided light-receiving mechanical stacked solar cell into an assembly.

[0004] In a first aspect, the present application provides a conductive backsheet for a double-sided light-receiving mechanically stacked solar cell, which is used to connect a first solar cell and a second solar cell in a stacked arrangement, comprising:

[0005] a substrate having a first side facing the first solar cell and a second side facing the second solar cell;

[0006] a first conductive layer at least partially exposed from the first side of the substrate, the first conductive layer being used to connect to the electrode of the first solar cell;

[0007] A second conductive layer is at least partially exposed from the second side of the substrate, and the second conductive layer is used for connecting to the electrode of the second solar cell.

[0008] Optionally, a first groove is formed on the first side of the substrate, and the first conductive layer is at least partially disposed in the first groove;

[0009] And / or, a second groove is formed on the second side of the substrate, and the second conductive layer is at least partially disposed in the second groove.

[0010] Optionally, the first conductive layer includes first connecting portions arranged at intervals, and the first connecting portions correspond one-to-one to the electrodes of the first solar cell;

[0011] And / or, the second conductive layer includes second connecting portions arranged at intervals, and the second connecting portions correspond one-to-one to the electrodes of the second solar cell.

[0012] Optionally, the first conductive layer includes a plurality of first conductive blocks and a plurality of second conductive blocks that are spaced apart.

[0013] Optionally, a first spacing region is provided between the first conductive block and the second conductive block, and the first conductive layer further includes a first transmission portion and a second transmission portion, the first transmission portion connects each of the first conductive blocks, and the second transmission portion connects each of the second conductive blocks.

[0014] Optionally, the second connecting portion includes a plurality of third conductive blocks and a plurality of fourth conductive blocks that are arranged at intervals.

[0015] Optionally, a second spacing area is provided between the third conductive block and the fourth conductive block, and the second conductive layer further includes a third transmission part and a fourth transmission part, the third transmission part connects each of the third conductive blocks, and the fourth transmission part connects each of the fourth conductive blocks.

[0016] Optionally, the material used for the first conductive layer includes a transparent conductive layer; and / or the material used for the second conductive layer includes a transparent conductive layer.

[0017] Optionally, the substrate is a transparent substrate.

[0018] Optionally, the width of the first connecting portion is less than or equal to the width of the electrode of the first battery corresponding to the first connecting portion;

[0019] And / or, the width of the second connecting portion is less than or equal to the width of the electrode of the second battery corresponding to the second connecting portion.

[0020] Optionally, the substrate includes at least one of glass, EPE, EVA, silicone, PET and TPT.

[0021] In a second aspect, the battery assembly provided by the present application includes a conductive backplane for a double-sided light-receiving mechanically stacked solar cell as described in any of the above items, a plurality of the first solar cells are connected to the first conductive layer, and a plurality of the second solar cells are connected to the second conductive layer.

[0022] In a third aspect, the photovoltaic system provided by the present application includes the above-mentioned battery assembly.

[0023] In the conductive backplane, battery assembly and photovoltaic system for the double-sided light-receiving mechanical stacked solar cells of the embodiment of the present application, the first solar cell is connected by the first conductive layer exposed from one side of the substrate, and the second solar cell is connected by the second conductive layer exposed from the other side of the substrate, so that the packaging of the first solar cell and the second solar cell arranged in a stacked manner can be achieved simultaneously. In one embodiment, the conductive backplane is a transparent conductive backplane. On the basis of simultaneously encapsulating the first solar cell and the second solar cell arranged in a stacked manner, the light passing through one solar cell can pass through the conductive backplane and enter the other solar cell, which can increase the absorbed light and improve the conversion efficiency. In another embodiment, the number of the first solar cell is multiple, and they are connected in series through the transparent conductive backplane to form a first solar cell string. The number of the second solar cell is multiple, and they are connected in series through the transparent conductive backplane to form a second solar cell string. In another embodiment, the first solar cell and the second solar cell can be respectively engaged with the first conductive layer and the second conductive layer of the conductive backplane, so that rapid packaging can be achieved, cost can be reduced and packaging efficiency can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 1 is a schematic plan view of a conductive backsheet for a double-sided light-receiving mechanically laminated solar cell according to an embodiment of the present application;

[0025] Figure 2 1 is a schematic cross-sectional view of a conductive backsheet for a double-sided light-receiving mechanically laminated solar cell according to an embodiment of the present application;

[0026] Figure 3 1 is a schematic cross-sectional view of a conductive backsheet for a double-sided light-receiving mechanically laminated solar cell according to an embodiment of the present application;

[0027] Figure 4 1 is a schematic plan view of a conductive backsheet for a double-sided light-receiving mechanically laminated solar cell according to an embodiment of the present application;

[0028] Figure 5 1 is a schematic plan view of a conductive backsheet for a double-sided light-receiving mechanically laminated solar cell according to an embodiment of the present application;

[0029] Figure 6 1 is a schematic plan view of a conductive backsheet for a double-sided light-receiving mechanically laminated solar cell according to an embodiment of the present application;

[0030] Figure 7 1 is a schematic cross-sectional view of a conductive backsheet for a double-sided light-receiving mechanically laminated solar cell according to an embodiment of the present application;

[0031] Figure 8 1 is a schematic cross-sectional view of a conductive backsheet for a double-sided light-receiving mechanically laminated solar cell according to an embodiment of the present application;

[0032] Figure 9 1 is a schematic plan view of a conductive backsheet for a double-sided light-receiving mechanically laminated solar cell according to an embodiment of the present application;

[0033] Figure 10 1 is a schematic cross-sectional view of a conductive backsheet for a double-sided light-receiving mechanically laminated solar cell according to an embodiment of the present application;

[0034] Figure 11 1 is a schematic cross-sectional view of a conductive backsheet for a double-sided light-receiving mechanically laminated solar cell according to an embodiment of the present application;

[0035] Figure 12 1 is a schematic plan view of a conductive backsheet for a double-sided light-receiving mechanically laminated solar cell according to an embodiment of the present application;

[0036] Figure 13 1 is a schematic plan view of a conductive backsheet for a double-sided light-receiving mechanically laminated solar cell according to an embodiment of the present application;

[0037] Figure 14 1 is a schematic plan view of a conductive backsheet for a double-sided light-receiving mechanically laminated solar cell according to an embodiment of the present application;

[0038] Figure 15 1 is a schematic cross-sectional view of a conductive backsheet for a double-sided light-receiving mechanically laminated solar cell according to an embodiment of the present application;

[0039] Figure 16 1 is a schematic cross-sectional view of a conductive backsheet for a double-sided light-receiving mechanically laminated solar cell according to an embodiment of the present application;

[0040] Figure 17 1 is a schematic cross-sectional view of a conductive backsheet for a double-sided light-receiving mechanically laminated solar cell according to an embodiment of the present application;

[0041] Figure 18 1 is a schematic plan view of a conductive backsheet for a double-sided light-receiving mechanically laminated solar cell according to an embodiment of the present application;

[0042] Figure 19 It is a cross-sectional schematic diagram of a conductive backplane for a double-sided light-receiving mechanically stacked solar cell according to an embodiment of the present application.

[0043] Description of main component symbols:

[0044] Bifacially-illuminated mechanically stacked solar cell 10, first solar cell 101, third conductive portion 1018, fourth conductive portion 1019, second solar cell 102, first conductive portion 1028, second conductive portion 1029, conductive backsheet 20, substrate 201, first side 2011, first plane 2013, first groove 2015, second side 2012, second plane 2014, second groove 2016;

[0045] The first conductive layer 21, the first conductive block 211, the second conductive block 212, the first spacer 213, the first buffer 214, the first transmission portion 215, the second transmission portion 216,

[0046] The second conductive layer 22, the third conductive block 221, the fourth conductive block 222, the second spacing area 223, the third transmission portion 225, the second buffer 224, the fourth transmission portion 226,

[0047] The transparent conductive layer 23 , the transparent connecting portion 231 , the first connecting portion 41 , and the second connecting portion 42 . DETAILED DESCRIPTION

[0048] In order to make the purpose, technical solutions and advantages of this application more clearly understood, the present application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0049] See also Figure 1 and Figure 2 The conductive backsheet 20 for the bifacially illuminated mechanically stacked solar cell 10 of the present application is used to connect the first solar cell 101 and the second solar cell 102 in a stacked arrangement. The conductive backsheet 20 includes a substrate 201, a first conductive layer 21, and a second conductive layer 22. The substrate 201 has a first side 2011 facing the first solar cell 101 and a second side 2012 facing the second solar cell 102. The first conductive layer 21 is at least partially exposed from the first side 2011 of the substrate 201 and is used to connect to the electrodes of the first solar cell 101. The second conductive layer 22 is at least partially exposed from the second side 2012 of the substrate 201 and is used to connect to the electrodes of the second solar cell 102.

[0050] The double-sided light-receiving mechanically stacked solar cell 10 of the present application embodiment uses a conductive backsheet 20. The first conductive layer 21 exposed from one side of the substrate 201 connects the first solar cell 101, and the second conductive layer 22 exposed from the other side of the substrate 201 connects the second solar cell 102. This can simultaneously achieve the packaging of the first solar cell 101 and the second solar cell 102 in a stacked arrangement. In one embodiment, the conductive backsheet 20 is a transparent conductive backsheet. On the basis of simultaneously encapsulating the first solar cell 101 and the second solar cell 102 in a stacked arrangement, light passing through one solar cell can pass through the conductive backsheet 20 and enter the other solar cell, thereby increasing the amount of light absorbed and improving the conversion efficiency. In another embodiment, there are multiple first solar cells 101, which are connected in series via the transparent conductive backsheet 20 to form a first solar cell string. There are also multiple second solar cells 102, which are connected in series via the transparent conductive backsheet 20 to form a second solar cell string. In yet another embodiment, the first solar cell 101 and the second solar cell 102 can be respectively engaged with the first conductive layer 21 and the second conductive layer 22 of the conductive backsheet 20. This can achieve rapid packaging, reduce costs, and improve packaging efficiency.

[0051] Please note that the first solar cell 101 can be the top cell and the second solar cell 102 can be the bottom cell; alternatively, the first solar cell 101 can be the bottom cell and the second solar cell 102 can be the top cell. The specific stacking direction of the first solar cell 101 and the second solar cell 102 is not limited here. For ease of explanation, the following description uses the example of the first solar cell 101 being the top cell and the second solar cell 102 being the bottom cell.

[0052] Specifically, the first conductive layer 21 is connected to the busbar of the first solar cell 101, and the second conductive layer 22 is connected to the busbar of the second solar cell 102. This allows for a wider busbar width, facilitating connection, reducing process complexity, and improving production efficiency. It is understood that in other examples, the first conductive layer 21 may be connected to the fine grid of the first solar cell 101, and the second conductive layer 22 may be connected to the fine grid of the second solar cell 102.

[0053] See also Figure 1 Specifically, a double-sided mechanically stacked solar cell 10 includes a first solar cell 101 and a second solar cell 102 arranged in a stacked configuration. The first solar cell 101 has an interdigital structure 11 on the surface facing the second solar cell 102, and the second solar cell 102 has an interdigital structure 11 on the surface facing the first solar cell 101. This eliminates the need for electrodes on the surface facing away from the opposite solar cell, preventing the electrodes from blocking sunlight directed toward the surface facing away from the opposite solar cell, thereby improving photoelectric conversion efficiency.

[0054] It can be understood that when the first solar cell 101 and the second solar cell 102 are both provided with a finger structure 11 on the surface facing the opposite side cell, a mechanical stacked solar cell 10 can be rotated 180°, and then the rotated mechanical stacked solar cell 10 can be connected in series with another non-rotated mechanical stacked solar cell 10 to form a battery assembly.

[0055] See also Figure 2 Specifically, the first conductive layer 21 includes a plurality of first conductive blocks 211 and a plurality of second conductive blocks 212 that are spaced apart. Thus, the first conductive blocks 211 and the second conductive blocks 212 can be connected to the two conductive portions of the interdigital structure 11 of the first solar cell 101, respectively.

[0056] Furthermore, a first spacer 213 may be provided between the first conductive block 211 and the second conductive block 212. Thus, the first spacer 213 is used to separate adjacent conductive blocks so as to insulate the adjacent conductive blocks from each other.

[0057] Similarly, the second conductive layer 22 includes a plurality of spaced third conductive blocks 221 and a plurality of fourth conductive blocks 222. Thus, the third conductive blocks 221 and the fourth conductive blocks 222 can be connected to two conductive portions in the interdigital structure 11 of the second solar cell 102, respectively.

[0058] Furthermore, a second spacer 223 may be provided between the third conductive block 221 and the fourth conductive block 222. Thus, the second spacer 223 is used to separate adjacent conductive blocks so as to insulate the adjacent conductive blocks from each other.

[0059] Specifically, in Figure 1 In the example, the first spacer 213 can be an insulating portion provided on the substrate 201. Specifically, the first spacer 213 can be filled with an insulating material such as glass, EPE, EVA, silicone, PET, and TPT to form the insulating portion. It is understood that in other examples, the first spacer 213 can be a gap, i.e., air-insulated, or a protrusion extending from the insulating base of the substrate 201 toward the first side 2011. The specific form of the first spacer 213 is not limited herein.

[0060] Similarly, in Figure 1In the example, the second spacer 223 can be an insulating portion provided on the substrate 201. Specifically, the second spacer 223 can be filled with an insulating material such as glass, EPE, EVA, silicone, PET, and TPT to form the insulating portion. It is understood that in other examples, the second spacer 223 can be a gap, i.e., air-insulated, or a protrusion extending from the insulating base of the substrate 201 toward the second side 2012. The specific form of the second spacer 223 is not limited herein.

[0061] Specifically, in Figure 1 In the example, the first solar cell 101 and the second solar cell 102 are both interdigitated back-contact crystalline silicon solar cells. The interdigitated structure 11 includes two electrodes, i.e., interdigitated electrodes, arranged alternately. The first conductive block 211 and the second conductive block 212 are respectively used to connect the two electrodes of the first solar cell 101. The third conductive block 221 and the fourth conductive block 222 are respectively used to connect the two electrodes of the second solar cell 102.

[0062] It can be understood that in some other embodiments, the first solar cell 101 and the second solar cell 102 can also be interdigitated back-contact thin-film solar cells, and the interdigitated structure 11 includes two conductive areas arranged alternately. The first conductive block 211 and the second conductive block 212 are respectively used to connect the two conductive areas of the first solar cell 101. The third conductive block 221 and the fourth conductive block 222 are respectively used to connect the two conductive areas of the second solar cell 102. In some other embodiments, the first solar cell 101 can be an interdigitated back-contact crystalline silicon solar cell, and the second solar cell 102 can be an interdigitated back-contact thin-film solar cell. In some other embodiments, the first solar cell 101 can be an interdigitated back-contact thin-film solar cell, and the second solar cell 102 can be an interdigitated back-contact crystalline silicon solar cell.

[0063] Note that thin-film cells can be used as bottom cells. This allows them to fully utilize their excellent low-light response and absorb sunlight reflected by the ground or other objects, thereby improving photoelectric conversion efficiency. Crystalline silicon cells can be used as top cells. This leverages their high conversion efficiency, thereby improving overall photoelectric conversion efficiency.

[0064] The rest of the explanations in this section are similar to those in the previous text. Please refer to the previous text. To avoid redundancy, they will not be repeated here.

[0065] See also Figure 3Optionally, the first conductive layer 21 includes a plurality of first conductive blocks 211, a plurality of second conductive blocks 212, a first transmission portion 215, and a second transmission portion 216. The first transmission portion 215 connects each first conductive block 211, and the second transmission portion 216 connects each second conductive block 212. In this way, the current collected by the first conductive blocks 211 and the second conductive blocks 212 can be respectively conducted out of the conductive backplane 20 via the first transmission portion 215 and the second transmission portion 216.

[0066] Specifically, the first transmission portion 215 and the second transmission portion 216 can be metal wires. Compared to the related art of using a whole surface of copper foil to transmit current, using metal wires to transmit current can reduce the amount of metal used, which is conducive to reducing costs.

[0067] In this embodiment, the first transmission portion 215 and the second transmission portion 216 are disposed within the substrate 201. The third transmission portion 225 and the fourth transmission portion 226 are also disposed within the substrate 201. This allows full utilization of the interior space of the substrate 201. Thus, the first conductive layer 21 is partially exposed from the first side 2011 of the substrate 201, and the second conductive layer 22 is partially exposed from the second side 2012 of the substrate 201.

[0068] Specifically, the first transmission portion 215 and the second transmission portion 216 are located at different depths in the substrate 201 . Thus, the first transmission portion 215 and the second transmission portion 216 can be staggered by utilizing the thickness of the conductive backplane 20 , so that the first transmission portion 215 and the second transmission portion 216 are insulated from each other.

[0069] Specifically, the orthographic projections of the first transmission portion 215 and the second transmission portion 216 on the first plane 2013 are staggered. In this way, the length and width of the conductive back plate 20 can be utilized to stagger the first transmission portion 215 and the second transmission portion 216.

[0070] See also Figure 4 It is understood that in other embodiments, the first transmission portion 215 and the second transmission portion 216 can be disposed on the first plane 2013 of the substrate 201. This eliminates the need to fabricate circuits within the substrate 201, thereby improving production efficiency. Thus, the first conductive layer 21 is entirely exposed from the first side 2011 of the substrate 201.

[0071] Specifically, in Figure 4 In the embodiment, the first conductive block 211 and the second conductive block 212 are both triangular. This makes the shape more regular, facilitates preparation, and helps improve production efficiency. It is understood that in other embodiments, the first conductive block 211 and the second conductive block 212 can be rectangular, square, circular, elliptical, or other shapes.

[0072] Specifically, in Figure 4In the embodiment, the first spacer 213 is rectangular. It is understood that in other embodiments, the first spacer 213 may be circular, annular, square, triangular, elliptical or other shapes.

[0073] Specifically, in Figure 4 In the embodiment, the first transmission portion 215 and the second transmission portion 216 are both straight. This results in a more regular shape, facilitating fabrication, improving production efficiency, and creating a neat appearance. It is understood that in other embodiments, the first transmission portion 215 and the second transmission portion 216 may both be curved or folded; the first transmission portion 215 may be straight, while the second transmission portion 216 may be curved or folded; or the first transmission portion 215 may be curved or folded, while the second transmission portion 216 may be straight.

[0074] Specifically, in Figure 4 In the embodiment, the first conductive blocks 211 and the second conductive blocks 212 are staggered in both the length and width directions of the substrate 201. In other words, between two adjacent columns of first conductive blocks 211, there is a column of second conductive blocks 212; between two adjacent rows of first conductive blocks 211, there is a row of second conductive blocks 212. This results in a greater degree of stagger between the first and second conductive blocks 211, avoiding the circuit confusion that can occur with a smaller stagger. Furthermore, this allows the first and second transmission portions 215, 216 to form straight lines, facilitating their fabrication.

[0075] It can be understood that in other embodiments, the first conductive blocks 211 and the second conductive blocks 212 may be staggered only in the length direction of the substrate 201 ; or may be staggered only in the length direction of the substrate 201 .

[0076] See also Figure 5 It is understood that in other embodiments, the third transmission portion 225 and the fourth transmission portion 226 can be disposed on the second plane 2014 of the substrate 201. This eliminates the need to fabricate circuits within the substrate 201, thereby improving production efficiency. Thus, the second conductive layer 22 is entirely exposed from the second side 2012 of the substrate 201.

[0077] Specifically, the first transmission portion 215 and the second transmission portion 216 may be transparent, so as to avoid the first transmission portion 215 and the second transmission portion 216 blocking sunlight, which is beneficial to improving the photoelectric conversion efficiency.

[0078] Similarly, the second conductive layer 22 includes a plurality of third conductive blocks 221, a plurality of fourth conductive blocks 222, a third transmission portion 225, and a fourth transmission portion 226. The third transmission portions 225 and the fourth transmission portions 226 are insulated from each other. The third transmission portions 225 connect each of the third conductive blocks 221, and the fourth transmission portions 226 connect each of the fourth conductive blocks 222. In this manner, the current collected by the third conductive blocks 221 and the fourth conductive blocks 222 can be respectively conducted out of the conductive backplate 20 via the third transmission portions 225 and the fourth transmission portions 226.

[0079] For the explanation and description of this part, please refer to the previous text. To avoid redundancy, we will not repeat it here.

[0080] See also Figure 6 Optionally, a double-sided light-receiving mechanically stacked solar cell 10 includes a first solar cell 101 and a second solar cell 102 arranged in a stacked manner. The first solar cell 101 is provided with an interdigital structure 11 on the surface facing the second solar cell 102, and the second solar cell 102 is not provided with an interdigital structure 11 on the surface facing the first solar cell 101. Specifically, the second solar cell 102 is provided with a first conductive portion 1028 on the side facing the first solar cell 101, and a second conductive portion 1029 on the side facing away from the first solar cell 101.

[0081] Please also refer to Figure 7 The first conductive layer 21 includes a first conductive block 211, a second conductive block 212, and a first spacer 213. The first conductive block 211 and the second conductive block 212 are respectively used to connect the two conductive portions of the interdigital structure 11 of the first solar cell 101. The first spacer 213 is used to separate adjacent conductive blocks so that the conductive blocks are insulated from each other.

[0082] Note that the second conductive layer 22 includes a third conductive block 221 and a second spacer 223. The third conductive block 221 is used to connect the first conductive portion 1028 of the second solar cell 102 facing the first solar cell 101. The second spacer 223 is used to separate adjacent conductive blocks so that the conductive blocks are insulated from each other.

[0083] exist Figure 6 In the example, the first solar cell 101 is an interdigitated back-contact crystalline silicon solar cell. The interdigitated structure 11 includes two electrodes, i.e., interdigitated electrodes, arranged alternately. The first conductive block 211 and the second conductive block 212 are respectively used to connect the two electrodes of the first solar cell 101. The second solar cell 102 is a double-sided contact crystalline silicon solar cell. The third conductive block 221 is used to connect the electrode on one side of the second solar cell 102.

[0084] It can be understood that in some other embodiments, the first solar cell 101 may be an interdigitated back-contact thin-film solar cell, and the second solar cell 102 may be a double-sided contact thin-film solar cell. In some other embodiments, the first solar cell 101 may be an interdigitated back-contact crystalline silicon solar cell, and the second solar cell 102 may be a double-sided contact thin-film solar cell. In some other embodiments, the first solar cell 101 may be an interdigitated back-contact thin-film solar cell, and the second solar cell 102 may be a double-sided contact crystalline silicon solar cell. The explanation of this part is similar to the previous text, and can be referred to the previous text. To avoid redundancy, it will not be repeated here.

[0085] See also Figure 8 Optionally, the first conductive layer 21 includes a plurality of first conductive blocks 211, a plurality of second conductive blocks 212, a first transmission portion 215, and a second transmission portion 216. The first transmission portion 215 and the second transmission portion 216 are insulated from each other. The first transmission portion 215 connects each first conductive block 211, and the second transmission portion 216 connects each second conductive block 212. In this way, the current collected by the first conductive blocks 211 and the second conductive blocks 212 can be respectively conducted out of the conductive backplane 20 via the first transmission portion 215 and the second transmission portion 216. The second conductive layer 22 includes a plurality of third conductive blocks 221 and a third transmission portion 225. The third transmission portion 225 connects each third conductive block 221. In this way, the current collected by the third conductive blocks 221 can be conducted out of the conductive backplane 20 via the third transmission portion 225. For explanations and descriptions of this part, please refer to the previous text. To avoid redundancy, they will not be repeated here.

[0086] See also Figure 9 Optionally, the double-sided light-receiving mechanically stacked solar cell 10 includes a first solar cell 101 and a second solar cell 102 arranged in a stacked manner. The first solar cell 101 does not have an interdigital structure 11 on the surface facing the second solar cell 102, and the second solar cell 102 does not have an interdigital structure 11 on the surface facing the first solar cell 101. Specifically, the second solar cell 102 has a first conductive portion 1028 on the side facing the first solar cell 101 and a second conductive portion 1029 on the side facing away from the first solar cell 101. The first solar cell 101 has a third conductive portion 1018 on the side facing the second solar cell 102 and a fourth conductive portion 1019 on the side facing away from the second solar cell 102.

[0087] Please also refer to Figure 10, please note that the first conductive layer 21 includes a first conductive block 211 and a first spacer 213. The first conductive block 211 is used to connect the third conductive portion 1018 of the first solar cell 101 facing the second solar cell 102. The first spacer 213 is used to space adjacent conductive blocks so that the conductive blocks are insulated from each other. The second conductive layer 22 includes a third conductive block 221 and a second spacer 223. The third conductive block 221 is used to connect the first conductive portion 1028 of the second solar cell 102 facing the first solar cell 101. The second spacer 223 is used to space adjacent conductive blocks so that the conductive blocks are insulated from each other.

[0088] exist Figure 9 In the example, the first solar cell 101 is a double-sided contact crystalline silicon solar cell, and the first conductive block 211 is used to connect the electrode of the first solar cell 101 on the side facing the second solar cell 102. The second solar cell 102 is a double-sided contact crystalline silicon solar cell, and the third conductive block 221 is used to connect the electrode of the second solar cell 102 on the side facing the first solar cell 101.

[0089] It is understood that in some other embodiments, the first solar cell 101 may be a double-sided contact thin-film solar cell, and the second solar cell 102 may be a double-sided contact thin-film solar cell. In other embodiments, the first solar cell 101 may be a double-sided contact crystalline silicon solar cell, and the second solar cell 102 may be a double-sided contact thin-film solar cell. In still other embodiments, the first solar cell 101 may be a double-sided contact thin-film solar cell, and the second solar cell 102 may be a double-sided contact crystalline silicon solar cell. The explanation of this part is similar to that of the previous text, and can be referred to the previous text. To avoid redundancy, it will not be repeated here.

[0090] See also Figure 11 Optionally, the first conductive layer 21 includes a plurality of first conductive blocks 211 and a first transmission portion 215, wherein the first transmission portion 215 connects each of the first conductive blocks 211. Thus, the current collected by the first conductive blocks 211 can be conducted out of the conductive backplane 20 via the first transmission portions 215. The second conductive layer 22 includes a plurality of third conductive blocks 221 and a third transmission portion 225, wherein the third transmission portion 225 connects each of the third conductive blocks 221. Thus, the current collected by the third conductive blocks 221 can be conducted out of the conductive backplane 20 via the third transmission portions 225.

[0091] Specifically, the first transmission part 215 can be arranged inside the substrate 201, such as Figure 11 As shown, it can also be provided on the first plane 2013 of the first side 2011 of the substrate 201, as shown Figure 12 The third transmission part 225 can be arranged inside the substrate 201, as shown. Figure 11As shown, it can also be provided on the second plane 2014 of the second side 2012 of the substrate 201, as shown in FIG. Figure 13 shown.

[0092] For other explanations and descriptions of this part, please refer to the previous text. To avoid redundancy, we will not repeat them here.

[0093] Please note that the above is only an example and does not limit the specific structure of the first solar cell 101 and the second solar cell 102. It is understood that the specific structure of the conductive backsheet 20 can be adaptively adjusted according to the specific structure of the first solar cell 101 and the second solar cell 102.

[0094] Optionally, substrate 201 is a transparent substrate. This allows sunlight to pass through substrate 201, preventing it from being blocked, thereby improving the photoelectric conversion efficiency of the mechanically stacked solar cell 10 with double-sided illumination. It can be understood that sunlight incident on one cell facing away from the opposite cell, after passing through that cell and being transmitted by substrate 201, can then enter the opposite cell and be utilized by it.

[0095] Specifically, the light transmittance of the substrate 201 is greater than 80%, for example, 80%, 82%, 85%, 87%, 89%, 90%, 92%, 95%, 97%, 99%, or 100%. This ensures that the light transmittance of the substrate 201 is within an appropriate range, thereby preventing sunlight from being blocked due to low light transmittance, thereby preventing low photoelectric conversion efficiency caused by shading of the substrate 201.

[0096] Optionally, the substrate 201 includes at least one of glass, EPE (pearl cotton), EVA (ethylene-vinyl acetate copolymer), silicone, PET (polyethylene glycol terephthalate) and TPT (polyvinyl fluoride composite film).

[0097] It can be understood that glass has a high transmittance to sunlight, is widely used, and is easily available, which is conducive to improving photoelectric conversion efficiency and production efficiency.

[0098] It can be understood that EPE can be waterproof, moisture-proof, shock-proof and collision-resistant, which is conducive to ensuring the reliability of battery components.

[0099] As you can understand, EVA is water-resistant and corrosion-resistant, flexible, and relatively soft, which can act as a buffer, helping to ensure the reliability of battery components. In addition, EVA can transmit light, which can be used by the battery to improve the photoelectric conversion efficiency.

[0100] As can be understood, organosilicon is resistant to high temperatures and highly water-repellent, which helps improve the reliability of the conductive backsheet 20. Furthermore, organosilicon has excellent electrical insulation properties, enabling electrical isolation between the first solar cell 101 and the second solar cell 102, thus avoiding current matching between the first solar cell 101 and the second solar cell 102, thereby avoiding efficiency limitations caused by current matching.

[0101] As you can understand, PET is impact-resistant and corrosion-resistant, which helps ensure the reliability of battery components. Furthermore, PET's high transparency minimizes light obstruction, which helps improve photoelectric conversion efficiency.

[0102] It can be understood that TPT has strong corrosion resistance and good insulation properties, which is conducive to ensuring the reliability of battery components.

[0103] In this embodiment, substrate 201 is a glass substrate. This helps improve photoelectric conversion efficiency and production efficiency. Furthermore, the first conductive layer 21 and the second conductive layer 22 can be provided on the glass substrate. Conductive glue or solder paste can be provided between the first conductive layer 21 and the electrode, and between the second conductive layer 22 and the electrode. This makes the electrical connection between the electrode and the conductive layer more stable.

[0104] In other embodiments, substrate 201 may include one, two, three, four, five, or all of glass, EPE, EVA, silicone, PET, and TPT. For example, substrate 201 may include glass, EPE, EVA, silicone, PET, and TPT. For another example, substrate 201 may include glass, EPE, EVA, silicone, and PET. For another example, substrate 201 may include glass, EPE, EVA, silicone, and PET. For another example, substrate 201 may include glass, EPE, EVA, and silicone. For another example, substrate 201 may include glass, EPE, and EVA. For another example, substrate 201 may include glass and EPE. For another example, substrate 201 may include glass. The specific form of substrate 201 is not limited herein.

[0105] Optionally, the material used for the first conductive layer 21 includes a transparent conductive layer or a metal; and / or the material used for the second conductive layer 22 includes a transparent conductive layer or a metal. Thus, various forms of the first conductive layer 21 and the second conductive layer 22 are provided, and can be selected according to actual conditions during the production process.

[0106] Specifically, in this embodiment, the transparent conductive layer is a transparent conductive oxide (TCO). TCO has high transmittance and anti-reflection properties, which can reduce the loss of sunlight and thus improve the photoelectric conversion efficiency.

[0107] It is understood that in other embodiments, the transparent conductive layer may be a metal film system, a compound film system, a polymer film system, a composite film system, etc. in addition to an oxide film system. Examples include EDOT (3,4-ethylenedioxythiophene) polymer PEDOT, metal mesh, carbon nanorod conductive film (CNB Films), silver nanowire (SNW), graphene, etc. The specific form of the transparent conductive layer is not limited herein.

[0108] Furthermore, TCO includes but is not limited to indium tin oxide (ITO), fluorine-doped tin oxide (FTO), and aluminum-doped zinc oxide (AZO). Specific types of TCO are not limited here.

[0109] In this embodiment, the TCO is indium tin oxide (ITO). ITO has high light transmittance, strong conductivity, low resistivity, and good stability and alkali resistance. Using ITO to form a transparent conductive layer helps improve the photoelectric conversion efficiency and reliability of the component.

[0110] Specifically, in this embodiment, the metal is aluminum. It is understood that in other embodiments, the metal may be one or more of copper, silver, aluminum, nickel, magnesium, iron, titanium, molybdenum, tungsten, and the like.

[0111] It is understood that the first conductive layer 21 and the second conductive layer 22 can be the same or different. In one example, the first conductive layer 21 and the second conductive layer 22 both comprise transparent conductive layers. In another example, the first conductive layer 21 comprises a transparent conductive layer and the second conductive layer 22 comprises a metal. In yet another example, the first conductive layer 21 comprises a metal and the second conductive layer 22 comprises a transparent conductive layer. In yet another example, both the first conductive layer 21 and the second conductive layer 22 comprise a metal. The specific forms of the first conductive layer 21 and the second conductive layer 22 are not limited herein.

[0112] See also Figure 14 Optionally, at least one of the first conductive layer 21 and the second conductive layer 22 includes a transparent conductive layer 23, the transparent conductive layer 23 includes transparent connecting portions 231 arranged at intervals, the transparent connecting portions 231 correspond one-to-one to the electrodes 1101 of the battery, and the width x of the transparent connecting portions 231 is greater than the width y of the electrodes 1101 corresponding to the transparent connecting portions 231.

[0113] Thus, even if the width of the transparent connecting portion 231 is greater than that of the corresponding electrode, it will not block sunlight. This can prevent the transparent connecting portion 231 from blocking sunlight that has passed through one cell and preventing it from being used by another cell, thereby improving photoelectric conversion efficiency. Furthermore, the larger width of the transparent connecting portion 231 improves electrical conductivity.

[0114] exist Figure 14 In the example shown, the first conductive layer 21 and the second conductive layer 22 are transparent; in other words, both are transparent conductive layers 23. It is understood that in other embodiments, the first conductive layer 21 may be transparent and the second conductive layer 22 may not be transparent; or the first conductive layer 21 may not be transparent and the second conductive layer 22 may be transparent.

[0115] Please also refer to Figure 2 When the first conductive block 211 and the second conductive block 212 are both transparent, the transparent connecting portion 231 may include the first conductive block 211 and the second conductive block 212. When the third conductive block 221 and the fourth conductive block 222 are both transparent, the transparent connecting portion 231 may include the third conductive block 221 and the fourth conductive block 222.

[0116] See also Figure 2 Optionally, the first conductive layer 21 is provided on a first plane 2013 of the first side 2011 of the substrate 201; and the second conductive layer 22 is provided on a second plane 2014 of the second side 2012 of the substrate 201. In this way, the first conductive layer 21 and the second conductive layer 22 are both provided on two planes of the substrate 201, eliminating the need for excessive processing of the substrate 201 and improving production efficiency.

[0117] It is understood that in other examples, only the first conductive layer 21 may be provided on the first plane 2013 of the first side 2011 of the substrate 201 ; and only the second conductive layer 22 may be provided on the second plane 2014 of the second side 2012 of the substrate 201 .

[0118] See also Figure 15 Optionally, a first groove 2015 is formed on the first side 2011 of the substrate 201, and the first conductive layer 21 is at least partially disposed in the first groove 2015; a second groove 2016 is formed on the second side 2012 of the substrate 201, and the second conductive layer 22 is at least partially disposed in the second groove 2016.

[0119] In this way, the first groove 2015 and the second groove 2016 can play a positioning role, which facilitates alignment and avoids offset when manufacturing the first conductive layer 21 and the second conductive layer 22, thereby improving production efficiency.

[0120] Specifically, in Figure 15In the example of , the first conductive layer 21 is entirely provided in the first groove 2015, and the thickness of the first conductive layer 21 is the same as the depth of the first groove 2015; Figure 16 In the example of , the first conductive layer 21 is entirely provided in the first groove 2015, and the thickness of the first conductive layer 21 is less than the depth of the first groove 2015; Figure 17 In the example, the first conductive layer 21 is partially disposed in the first groove 2015, and the thickness of the first conductive layer 21 is greater than the depth of the first groove 2015. The specific relationship between the first conductive layer 21 and the first groove 2015 is not limited herein.

[0121] Similarly, in Figure 15 In the example of , the second conductive layer 22 is entirely provided in the second groove 2016, and the thickness of the second conductive layer 22 is the same as the depth of the second groove 2016; Figure 16 In the example of , the second conductive layer 22 is entirely provided in the second groove 2016, and the thickness of the second conductive layer 22 is less than the depth of the second groove 2016; Figure 17 In the example, the second conductive layer 22 is partially disposed in the second groove 2016, and the thickness of the second conductive layer 22 is greater than the depth of the second groove 2016. The specific relationship between the second conductive layer 22 and the second groove 2016 is not limited herein.

[0122] It can be understood that in other embodiments, a first groove 2015 can be formed on the first side 2011 of the substrate 201, the first conductive layer 21 is at least partially disposed in the first groove 2015, and the second groove 2016 is not formed on the second side 2012 of the substrate 201; the first groove 2015 can be not formed on the first side 2011 of the substrate 201, a second groove 2016 can be formed on the second side 2012 of the substrate 201, and the second conductive layer 22 is at least partially disposed in the second groove 2016.

[0123] See also Figure 18 Optionally, the first conductive layer 21 includes first connecting portions 41 arranged at intervals, and the first connecting portions 41 correspond one-to-one to the electrodes 1101 of the first solar cell 101; the second conductive layer 22 includes second connecting portions 42 arranged at intervals, and the second connecting portions 42 correspond one-to-one to the electrodes 1101 of the second solar cell 102.

[0124] In this way, the first conductive layer 21 is connected to the electrode 1101 of the first solar cell 101 through the first connecting portion 41 .

[0125] Specifically, the substrate 201 is a transparent substrate, the width a of the first connecting portion 41 is less than or equal to the width b of the electrode 1101 of the first battery 101 corresponding to the first connecting portion 41, and the width c of the second connecting portion 42 is less than or equal to the width d of the electrode 1101 of the second battery 102 corresponding to the second connecting portion 42.

[0126] In this way, while ensuring electrical connection between the first connecting portion 41 and the electrode 1101 of the first solar cell 101, the first connecting portion 41 can be made relatively small, avoiding the situation where an overly large first connecting portion 41 blocks sunlight passing through the first solar cell 101, thereby improving photoelectric conversion efficiency. Furthermore, since the first connecting portion 41 is relatively small, the raw materials used in the first conductive layer 21 can be reduced, thereby reducing costs. Similarly, the second connecting portion 42 is relatively small, which is beneficial for improving photoelectric conversion efficiency and reducing costs.

[0127] It can be understood that in other embodiments, the width a of the first connecting portion 41 may be less than or equal to the width b of the electrode 1101 corresponding to the first connecting portion 41, and the width c of the second connecting portion 42 may be greater than the width d of the electrode 1101 corresponding to the second connecting portion 42; or the width a of the first connecting portion 41 may be greater than the width b of the electrode 1101 corresponding to the first connecting portion 41, and the width c of the second connecting portion 42 may be less than or equal to the width d of the electrode 1101 corresponding to the second connecting portion 42.

[0128] Optionally, when assembling the first solar cell 101 and the conductive backsheet 20, some connection points can be selected from the electrode 1101 of the first solar cell 101 and connected to the first connection portion 41 accordingly. When assembling the second solar cell 102 and the conductive backsheet 20, some connection points can be selected from the electrode 1101 of the second solar cell 102 and connected to the second connection portion 42 accordingly. This can reduce the difficulty of the alignment process and help improve production efficiency.

[0129] Please note that when the first solar cell 101 has an interdigital structure 11 on the surface facing the second solar cell 102, the first connecting portion 41 may include a plurality of first conductive blocks 211 and a plurality of second conductive blocks 212. The first conductive blocks 211 and the second conductive blocks 212 are respectively used to connect the two conductive portions of the interdigital structure 11 of the first solar cell 101. When the first solar cell 101 does not have an interdigital structure 11 on the surface facing the second solar cell 102, the first connecting portion 41 may include a plurality of first conductive blocks 211.

[0130] Similarly, when the second solar cell 102 has an interdigital structure 11 on the surface facing the first solar cell 101, the second connecting portion 42 includes a plurality of third conductive blocks 221 and a plurality of fourth conductive blocks 222. The third conductive blocks 221 and the fourth conductive blocks 222 are respectively used to connect two conductive portions in the interdigital structure 11 of the second solar cell 102. When the second solar cell 102 does not have an interdigital structure 11 on the surface facing the first solar cell 101, the second connecting portion 42 includes a plurality of third conductive blocks 221.

[0131] See also Figure 19 The conductive backsheet 20 may include a first buffer member 214 disposed in the first spacer 213; and a second buffer member 224 disposed in the second spacer 223. Thus, the first buffer member 214 can protect the first solar cell 101, and the second buffer member 224 can protect the second solar cell 102, thereby improving the reliability of the battery assembly.

[0132] Specifically, the first buffer member 214 includes at least one of EPE, EVA, and PET. The explanation and description of EPE, EVA, and PET can be found in the above text, and will not be repeated here to avoid redundancy.

[0133] Specifically, the distance h between the top surface of the first buffer 214 and the top surface of the first connection portion 41 is greater than the thickness of the electrode 1101 of the first solar cell 101. Similarly, the distance H between the top surface of the second buffer 224 and the top surface of the second connection portion 42 is greater than the thickness of the electrode 1101 of the second solar cell 102.

[0134] Thus, after the first solar cell 101 is assembled to the conductive backsheet 20, the first buffer 214 is in a compressed state, which can better support and protect the first solar cell 101. After the second solar cell 102 is assembled to the conductive backsheet 20, the second buffer 224 is in a compressed state, which can better support and protect the second solar cell 102.

[0135] It can be understood that in other embodiments, the conductive backplane 20 only includes the first buffer member 214 provided in the first spacer area 213, and does not include the second buffer member 224 provided in the second spacer area 223; the conductive backplane 20 may not include the first buffer member 214 provided in the first spacer area 213, and only includes the second buffer member 224 provided in the second spacer area 223.

[0136] The battery assembly of the embodiment of the present application includes a conductive backplane 20 for the double-sided mechanical stacked solar cell 10 of any of the above items, multiple first solar cells 101 are connected to the first conductive layer 21, and multiple second solar cells 102 are connected to the second conductive layer 22.

[0137] The battery assembly of the embodiment of the present application connects the first solar cell 101 through the first conductive layer 21 exposed from one side of the substrate 201, and connects the second solar cell 102 through the second conductive layer 22 exposed from the other side of the substrate 201, so that the double-sided light-receiving mechanical stacked solar cell 10 can be packaged into a component.

[0138] Specifically, the battery assembly may further include a first transparent backsheet, which is disposed on the side of the first solar cell 101 facing away from the conductive backsheet 20; and / or the battery assembly may further include a second transparent backsheet, which is disposed on the side of the second solar cell 102 facing away from the conductive backsheet 20. In this way, the double-glass design can further protect the first solar cell 101 and the second solar cell.

[0139] It can be understood that when a glass substrate is provided on the side of the first solar cell 101 facing away from the conductive backplane 20, the first transparent backplane can be omitted; when a glass substrate is provided on the side of the second solar cell 102 facing away from the conductive backplane 20, the second transparent backplane can be omitted.

[0140] In addition, the battery assembly may further include a transparent organic adhesive film, which can be used to laminate and package the double-sided light-receiving mechanical stacked solar cell 10, the conductive backplane 20, the transparent organic adhesive film, the first transparent backplane and the second transparent backplane.

[0141] The photovoltaic system of the embodiment of the present application includes the above-mentioned battery assembly.

[0142] The photovoltaic system of the embodiment of the present application connects the first solar cell 101 through the first conductive layer 21 exposed from one side of the substrate 201, and connects the second solar cell 102 through the second conductive layer 22 exposed from the other side of the substrate 201, so that the double-sided light-receiving mechanical stacked solar cell 10 can be packaged into a component.

[0143] The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A conductive back sheet for a double-sided light-receiving mechanically stacked solar cell, used to connect a first solar cell and a second solar cell in a stacked arrangement, characterized in that: include: a substrate having a first side facing the first solar cell and a second side facing the second solar cell; the substrate comprising an insulating base; a first conductive layer at least partially exposed from the first side of the substrate, the first conductive layer being used to connect to the electrode of the first solar cell; a second conductive layer at least partially exposed from the second side of the substrate, the second conductive layer being used for connecting to the electrode of the second solar cell; The first conductive layer includes a plurality of first conductive blocks and a plurality of second conductive blocks that are spaced apart from each other. The first conductive layer also includes a first transmission portion and a second transmission portion, wherein the first transmission portion connects each of the first conductive blocks and the second transmission portion connects each of the second conductive blocks. The second conductive layer includes a plurality of third conductive blocks and a plurality of fourth conductive blocks arranged at intervals. The second conductive layer also includes a third transmission part and a fourth transmission part. The third transmission part connects each of the third conductive blocks, and the fourth transmission part connects each of the fourth conductive blocks.

2. The conductive back sheet for a double-sided light-receiving mechanically laminated solar cell according to claim 1, characterized in that: A first groove is formed on the first side of the substrate, and the first conductive layer is at least partially disposed in the first groove; And / or, a second groove is formed on the second side of the substrate, and the second conductive layer is at least partially disposed in the second groove.

3. The conductive back sheet for a double-sided light-receiving mechanically laminated solar cell according to claim 1, characterized in that: The first conductive layer includes first connecting portions arranged at intervals, the first connecting portions corresponding one-to-one to the electrodes of the first solar cell, and the first connecting portions including the first conductive blocks and the second conductive blocks; And / or, the second conductive layer includes second connecting portions arranged at intervals, the second connecting portions correspond one-to-one to the electrodes of the second solar cell, and the second connecting portions include the third conductive block and the fourth conductive block.

4. The conductive back sheet for a double-sided light-receiving mechanically stacked solar cell according to any one of claims 1 to 3, characterized in that: The material used for the first conductive layer includes a transparent conductive layer; and / or the material used for the second conductive layer includes a transparent conductive layer.

5. The conductive back sheet for a double-sided light-receiving mechanically stacked solar cell according to any one of claims 1 to 3, characterized in that: The substrate is a transparent substrate.

6. The conductive back sheet for a double-sided light-receiving mechanically laminated solar cell according to claim 5, characterized in that: The width of the first connecting portion is less than or equal to the width of the electrode of the first battery corresponding to the first connecting portion; And / or, the width of the second connecting portion is less than or equal to the width of the electrode of the second battery corresponding to the second connecting portion.

7. The conductive back sheet for a double-sided light-receiving mechanically laminated solar cell according to any one of claims 1 to 3, characterized in that: The substrate includes at least one of glass, EPE, EVA, silicone, PET and TPT.

8. A battery assembly, characterized in that: The conductive backplane for a double-sided light-receiving mechanically stacked solar cell comprises the conductive backplane according to any one of claims 1 to 7, wherein a plurality of the first solar cells are connected to the first conductive layer, and a plurality of the second solar cells are connected to the second conductive layer.

9. A photovoltaic system, characterized in that: A battery assembly comprising the battery assembly of claim 8.

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