Back contact solar cell and photovoltaic module

Abstract

The utility model belongs to the technical field of photovoltaic cell manufacturing, and particularly relates to a back contact solar cell and a photovoltaic module, and the cell comprises a substrate, an electrode structure and a plurality of first insulating blocks. The substrate has an electrode region and a non-electrode region. The plurality of first insulating blocks are arranged facing the electrode structures and attached to the corresponding electrode structures respectively, the plurality of first insulating blocks comprise first edge insulating blocks adjacent to the non-electrode areas, and the first edge insulating blocks are provided with first edges close to the non-electrode areas and second edges away from the non-electrode areas. The first distance between the center of the electrode structure provided with the first edge insulating block and the first edge is smaller than the second distance between the center of the electrode structure provided with the first edge insulating block and the second edge, so that the first edge insulating block is ensured not to occupy a non-electrode area while the insulating effect is ensured by the first edge insulating block; therefore, not only is the use amount of the insulating material reduced to improve the warping problem of the battery, but also the printing yield of the battery is improved, and the processing problems such as poor slicing required later are avoided.

Description

Technical Field

[0001] The present application belongs to the field of photovoltaic cell manufacturing technology, and in particular relates to a back-contact solar cell and a photovoltaic module. Background Art

[0002] In back-contact solar cells (BC cells), the positive and negative electrodes are on the back of the cell, which makes short circuits easy to occur when interconnected. Therefore, insulating materials are needed in the production process of BC cells to ensure insulation between opposite electrodes.

[0003] However, during the insulating material coating process, the insulating material easily extends to the non-electrode area of ​​the substrate after curing. The larger the area occupied by the insulating material in the non-electrode area, the more the amount of insulating material used will increase, and the substrate will become dirty after the insulating material is coated, which is not conducive to improving the battery printing yield and is prone to process problems such as poor slicing. Utility Model Content

[0004] The present application provides a back-contact solar cell and photovoltaic module to solve the technical problem of low yield rate of existing battery printing.

[0005] According to one aspect of the present application, a back-contact solar cell is provided, comprising a substrate, an electrode structure, and a plurality of first insulating blocks. The electrode structure is provided on one side surface of the substrate, and the substrate has an electrode region where the electrode structure is provided and a non-electrode region where the electrode structure is not provided. The plurality of first insulating blocks are provided facing the electrode structure and are respectively attached to the corresponding electrode structures, and the plurality of first insulating blocks include a first edge insulating block adjacent to the non-electrode region, the first edge insulating block having a first edge close to the non-electrode region and a second edge away from the non-electrode region. The first distance d1 between the center of the electrode structure provided with the first edge insulating block and the first edge is smaller than the second distance d2 between the center and the second edge.

[0006] In an optional solution of the present application, there is one electrode area, and the non-electrode area is the edge area of ​​the substrate.

[0007] In an optional solution of the present application, there are multiple electrode areas, and two adjacent electrode areas are spaced apart in the second direction. The non-electrode area is the edge area of ​​the substrate in the second direction and / or the spaced area between two adjacent electrode areas.

[0008] In an optional solution of the present application, when the non-electrode area is an edge area of ​​the substrate, the ratio between the first distance d1 and the second distance d2 is 0.17 to 0.87.

[0009] In an optional solution of the present application, when the non-electrode area is an edge area of ​​the substrate, the first distance d1 is 0.08-0.4 mm, and the second distance d2 is 0.08-0.46 mm.

[0010] In an optional solution of the present application, when the non-electrode region is the spacing region between two adjacent electrode regions, the ratio of the first spacing d1 to the second spacing d2 is 0.17 to 0.55.

[0011] In an optional solution of the present application, when the non-electrode area is an edge area of ​​the substrate, the first distance d1 is 0.08-0.25 mm, and the second distance d2 is 0.081-0.46 mm.

[0012] In an optional solution of the present application, the difference between the second distance d2 and the first distance d1 is greater than 0 and not greater than 0.38 mm.

[0013] In an optional solution of the present application, the width of the first edge insulating block is W1, the distance between the first edge insulating block and the edge of the non-electrode area away from the first edge insulating block is D1, and the ratio of D1 to W1 is 0.033-0.067.

[0014] In an optional solution of the present application, in each electrode region, along the second direction and in the direction from the non-electrode region toward the electrode region, the lengths of the plurality of first insulating blocks located at the end portions are sequentially reduced.

[0015] In an optional solution of the present application, the multiple first insulating blocks also include multiple first central insulating blocks and second edge insulating blocks, and the multiple first central insulating blocks are located between the first edge insulating blocks and the second edge insulating blocks in the second direction, and the length difference between the first edge insulating blocks and the second edge insulating blocks is 2-4 mm.

[0016] In an optional solution of the present application, the width of the edge region of the substrate in the second direction is greater than 0.2 mm.

[0017] In an optional solution of the present application, the width of the spacing region between two adjacent electrode regions in the second direction is greater than 0.1 mm.

[0018] According to another aspect of the present application, a photovoltaic module is provided, which includes at least one back-contact solar cell as described above.

[0019] In an optional solution of the present application, the photovoltaic component also includes an electrical connection line, which is connected to the electrode structure of the first polarity. The first insulating block is located between the electrical connection line and the electrode structure of the second polarity, and the first polarity is opposite to the second polarity.

[0020] In an optional solution of the present application, the electrode structure is extended along the first direction. The photovoltaic module further includes a busbar electrode extended along the second direction, connected to the electrode structure with the same polarity, and located between the electrical connection line and the first insulating block.

[0021] In an optional solution of the present application, the bus electrode is provided with a plurality of connection points arranged at intervals, and a plurality of first insulating blocks are arranged between the connection points adjacent to the non-electrode area and the non-electrode area.

[0022] In an optional solution of the present application, the back-contact solar cell also includes a plurality of second insulating blocks arranged between two adjacent connection points, the plurality of second insulating blocks are arranged at intervals and there is an electrode structure between two adjacent second insulating blocks; and / or, the plurality of second insulating blocks are connected into one.

[0023] In an optional solution of the present application, the widths of at least two positions of the bus electrode in its extension direction are unequal.

[0024] In an optional solution of the present application, the back-contact solar cell further includes third insulating blocks disposed on both sides of the connection point, and the third insulating blocks on both sides of the connection point are symmetrically arranged.

[0025] In summary, the back-contact solar cell and photovoltaic module provided by this application have at least the following beneficial effects:

[0026] In the back-contact solar cell of the present application, a first edge insulating block is provided on the electrode structure adjacent to the non-electrode region, and a first spacing d1 between the center of the electrode structure and the first edge of the first edge insulating block close to the non-electrode region is made smaller than a second spacing d2 between the electrode structure and the second edge of the first edge insulating block away from the non-electrode region. In this way, after the insulating material solidifies and stretches, the width of the first edge insulating block on both sides of the electrode structure differs, and the width of the first edge insulating block close to the non-electrode region is relatively small, while the width of the first edge insulating block away from the non-electrode region is relatively large. The first edge insulating block ensures the insulation effect while ensuring that the first edge insulating block does not occupy the non-electrode region. This not only reduces the amount of insulating material used to improve the warping problem of the battery, but also avoids the insulating material from overflowing from the non-electrode region to the other side of the battery to improve the glue overflow problem on the front of the battery, but also improves the battery printing yield and avoids process problems such as poor slicing required later. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] To more clearly illustrate the specific embodiments of this application or the technical solutions in the prior art, the following briefly introduces the drawings required for the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be derived from these drawings without inventive effort.

[0028] Figure 1 A schematic diagram of a partial structure of a photovoltaic module provided in an embodiment of the present application;

[0029] Figure 2 A schematic diagram of another partial structure of a photovoltaic module provided in an embodiment of the present application;

[0030] Figure 3 A schematic diagram of a partial structure of a back-contact solar cell provided in an embodiment of the present application;

[0031] Figure 4 for Figure 3 An enlarged schematic diagram of the circled part in FIG.

[0032] Figure 5 A schematic diagram of another partial structure of a back-contact solar cell provided in an embodiment of the present application;

[0033] Figure 6 for Figure 5 An enlarged schematic diagram of the circled part.

[0034] The reference numerals are as follows:

[0035] 100. Back contact solar cell;

[0036] 10. Substrate; 11. Electrode area; 12. Non-electrode area;

[0037] 20. Electrode structure;

[0038] 30, first insulating block; 30A, first edge insulating block; 30B, first center insulating block; 30C, second edge insulating block;

[0039] 40. Second insulating block;

[0040] 50. The third insulating block;

[0041] 200, busbar electrode;

[0042] L1, first direction; L2, second direction. DETAILED DESCRIPTION

[0043] In order to make the above and other features and advantages of the present application more clear, the present invention is further described below with reference to the accompanying drawings. It should be understood that the specific embodiments given herein are for the purpose of explaining to those skilled in the art and are only exemplary and not restrictive.

[0044] Furthermore, the use of "first" or "second" in describing features is for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features identified. Features identified as "first" or "second" may explicitly or implicitly include at least one of the identified features. The use of the word "plurality" generally implies at least two, such as two or three, unless otherwise specifically defined.

[0045] refer to Figure 1 and Figure 2 The photovoltaic module of the embodiment of the present application includes at least one back-contact solar cell 100. Specifically, the number of back-contact solar cells 100 in the photovoltaic module can be one or more. When the number of back-contact solar cells 100 in the photovoltaic module is multiple, the multiple back-contact solar cells 100 can be connected in series to form multiple cell strings. The multiple cell strings can be connected in series, in parallel, or in a combination of series and parallel to achieve current bus output. For example, a bus bar can be used to connect two cell strings, and a welding ribbon (also called a welding bar) can be used to connect multiple back-contact solar cells 100.

[0046] When a photovoltaic module is formed by the back-contact solar cells 100 according to the embodiment of the present application, adjacent back-contact solar cells 100 are electrically connected and fixed by welding strips to achieve connection between the plurality of back-contact solar cells 100 , thereby forming a photovoltaic module.

[0047] refer to Figures 3 to 6 The back-contact solar cell 100 includes a substrate 10 , an electrode structure 20 and a plurality of first insulating blocks 30 .

[0048] The electrode structure 20 is disposed on one surface of the substrate 10. When the back-contact solar cell 100 is installed, the surface that faces away from the light is called the backlight surface (i.e., the surface on which the electrode structure 20 is disposed), while the surface facing the light is called the light-receiving surface (also known as the front surface). The electrode structure 20 includes two types of electrode structures 20 of opposite polarity. These two types of electrode structures 20 are alternately arranged on the backlight surface, and one of the two types of electrode structures 20 can be a positive electrode gridline, and the other a negative electrode gridline.

[0049] After the electrode structure 20 is disposed on the substrate 10, the substrate 10 actually includes two different functional areas. The area of ​​the substrate 10 where the electrode structure 20 is disposed can be referred to as the electrode area 11, while the area of ​​the substrate 10 where the electrode structure 20 is not disposed can be referred to as the non-electrode area 12. In other words, the substrate 10 includes the electrode area 11 where the electrode structure 20 is disposed and the non-electrode area 12 where the electrode structure 20 is not disposed.

[0050] In some embodiments, the substrate 10 may be a silicon wafer having a PN junction. The non-electrode region 12 may be an edge region of the substrate 10 (i.e., a cell edge region) or a cutting path region located in the middle of the substrate 10 for cutting, as will be described in detail below.

[0051] Multiple first insulating blocks 30 are arranged facing the electrode structure 20 and attached to corresponding electrode structures 20 to provide short-circuit protection for the battery. To further enhance the insulation and adhesion of each first insulating block 30, the first insulating block 30 can be extended to the area of ​​the substrate 10 adjacent to the electrode structure 20, thereby attaching to both the electrode structure 20 and the substrate 10. This significantly improves the connection reliability between the first insulating block 30 and the electrode structure 20 and prevents the first insulating block 30 from peeling off from the electrode structure 20.

[0052] The multiple first insulating blocks 30 include a first edge insulating block 30A adjacent to the non-electrode region 12 (i.e., the outermost first insulating block 30 among the multiple first insulating blocks 30), and the first edge insulating block 30A has a first edge 31 close to the non-electrode region 12 and a second edge 32 away from the non-electrode region 12.

[0053] The first spacing d1 between the center of the electrode structure 20 provided with the first edge insulating block 30A and the first edge 31 is smaller than the second spacing d2 between the center of the electrode structure 20 and the second edge 32. In other words, the first edge insulating block 30A is asymmetrically distributed along the center of the first electrode 20, and with the center of the first electrode 20 as a reference, the width of the first edge insulating block 30A on the side close to the non-electrode region 12 is smaller than the width of the first edge insulating block 30A on the side away from the non-electrode region 12. In addition, since the first electrode 20 is generally a gate line structure with a certain width, the "center of the first electrode 20" here refers to the width of the first electrode 20 in its width direction (i.e., Figure 4 The center of the L2 direction).

[0054] Exemplarily, the electrode structure 20 can extend along the first direction L1, then the first edge 31 and the second edge 32 of the first edge insulating block 30A refer to the two edges (also called boundaries) of the first edge insulating block 30A in the second direction L2, and the second direction L2 intersects with the first direction L1. Preferably, the second direction L2 is perpendicular to the first direction L1, that is, the first direction L1 is the length direction of the electrode structure 20, and the second direction L2 is the width direction of the electrode structure 20.

[0055] The first insulating block 30 is typically formed by curing an insulating material onto the electrode structure 20 and the substrate 10. Specifically, the insulating material may be an insulating adhesive, which is cured onto the electrode structure 20 and the substrate 10 to form an insulating adhesive block structure, thereby achieving a good insulation effect. Of course, the first insulating block 30 may also be other solid insulating materials, such as plastic, glass, etc.

[0056] It should be noted that, since the insulating material is easily diffused to the non-electrode area 12 (such as the edge area or the cutting path area) after solidification and extension, it may cause process problems such as contamination of the substrate 10 and poor identification and slicing of the cutting path area during the insulating material coating process. Therefore, in the back-contact solar cell 100 of the present application, a first edge insulating block 30A is provided on the electrode structure 20 adjacent to the non-electrode area 12, and a first spacing d1 between the center of the electrode structure 20 and a first edge 31 of the first edge insulating block 30A close to the non-electrode area 12 is made smaller than a second spacing d2 between the center of the electrode structure 20 and a second edge 32 of the first edge insulating block 30A away from the non-electrode area 12. In this way, when the insulating material is solidified and extended, the width of the first edge insulating block 30A on both sides of the center of the electrode structure 20 is different, and the width of the first edge insulating block 30A on the side close to the non-electrode area 12 is relatively small, while the width of the first edge insulating block 30A on the side away from the non-electrode area 12 is relatively large. The first edge insulating block 30A ensures the insulation effect while also ensuring that the first edge insulating block 30A after solidification and extension does not occupy the non-electrode area 12. This not only reduces the amount of insulating material used to improve the warping problem of the battery, avoids the insulating material from overflowing from the non-electrode area 12 to the other side of the battery (i.e., the front) to improve the glue overflow problem on the front of the battery, but also improves the battery printing yield and avoids process problems such as poor slicing required later.

[0057] Specifically, the shape of the first edge insulating block 30A may be a strip or a block, wherein the first edge 31 and the second edge 32 of the first edge insulating block 30A may include straight line segments and / or curved line segments.

[0058] For example, when the first edge 31 and the second edge 32 of the first edge insulating block 30A only include straight line segments, the first edge 31 and the second edge 32 are parallel to the center line of the first electrode 20. At this time, the distance from any point on the first edge 31 to the center of the electrode structure 20 can be selected as the first spacing d1, and the distance from any point on the second edge 32 to the center of the electrode structure 20 can be selected as the second spacing d2.

[0059] When the first edge 31 and the second edge 32 of the first edge insulating block 30A include curved segments, the curved segments can form a peak structure and / or a valley structure, and the distance from the maximum vertex (the vertex farthest from the electrode structure 20) among all the peak structures on the first edge 31 to the center of the electrode structure 20 can be selected as the first spacing d1, and the distance from the maximum vertex (the vertex farthest from the electrode structure 20) among all the peak structures on the second edge 32 to the center of the electrode structure 20 can be selected as the second spacing d2.

[0060] Alternatively, the average value of the distances from the vertices of all the peak structures on the first edge 31 to the center of the electrode structure 20 is selected as the first spacing d1, and the average value of the distances from the vertices of all the peak structures on the second edge 32 to the center of the electrode structure 20 is selected as the second spacing d2.

[0061] Alternatively, the distance from the lowest point of all the trough structures on the first edge 31 (i.e., the vertex closest to the electrode structure 20) to the center of the electrode structure 20 is selected as the first spacing d1, and the distance from the lowest point of all the trough structures on the second edge 32 (i.e., the vertex closest to the electrode structure 20) to the center of the electrode structure 20 is selected as the second spacing d2.

[0062] Alternatively, the average value of the distances from the vertices of all the trough structures on the first edge 31 to the center of the electrode structure 20 is selected as the first spacing d1, and the average value of the distances from the vertices of all the trough structures on the second edge 32 to the center of the electrode structure 20 is selected as the distance to the center of the electrode structure 20 as the second spacing d2.

[0063] Alternatively, the average value of the distances from the vertices of all the peaks and troughs on the first edge 31 to the center of the electrode structure 20 is selected as the first spacing d1, and the average value of the distances from the vertices of all the peaks and troughs on the second edge 32 to the center of the electrode structure 20 is selected as the distance to the center of the electrode structure 20 as the second spacing d2.

[0064] In some optional implementations, the difference between the second spacing d2 and the first spacing d1 is greater than 0 and not greater than 0.38 mm. For example, the difference between the first spacing d1 and the second spacing d2 can be 0.1, 0.12, 0.15, 0.18, 0.2, 0.22, 0.25, 0.28, 0.3, 0.32, 0.35, 0.38, etc. In this way, the first edge insulating block 30A can sufficiently cover the electrode structure 20 and the substrate 10 close to the non-electrode area 12 without exceeding the non-electrode area 12 of the substrate 10, thereby achieving the purpose of optimizing the surface of the substrate 10, and also avoiding the insulating material from overflowing from the non-electrode area 12 to the front of the battery to improve the problem of glue overflow on the front of the battery, and improve the battery printing yield and avoid process problems such as poor slicing required later.

[0065] In some optional implementations, the width of the first edge insulating block 30A in the second direction L2 is W1, the distance between the first edge insulating block 30A and the edge of the non-electrode region 12 away from the first edge insulating block 30A is D1, and the ratio of D1 to W1 is 0.033-0.067.

[0066] It will be appreciated that the width W1 of the first edge insulating block 30A herein refers to the dimension of the first edge insulating block 30A in the second direction L2. The edge of the non-electrode region 12 distal from the first edge insulating block 30A refers to the outermost edge or boundary of the substrate 10, and also the outermost edge or boundary of the battery. In other words, the distance D1 between the first edge insulating block 30A and the edge of the non-electrode region 12 distal from the first edge insulating block 30A can also be referred to as the width of the non-electrode region 12 in the second direction L2.

[0067] For example, the ratio between D1 and W1 can be 0.033, 0.037, 0.04, 0.043, 0.047, 0.05, 0.053, 0.057, 0.06, 0.067, etc. Thus, making the ratio between D1 and W1 any value within the above range can ensure a high degree of matching between the width of the first edge insulating block 30A and the width of the non-electrode region 12 in the second direction L2, thereby maximizing the optimization of the substrate 10 surface, thereby improving the battery printing yield and avoiding process problems such as poor slicing required later.

[0068] refer to Figure 3 and Figure 4, there is only one electrode region 11, and the non-electrode region 12 is the edge region of the substrate 10. In this case, the entire cell does not need to be cut. After the electrode structure 20 is set on the substrate 10, the central portion of the substrate 10 is used to set the electrode structure 20 to form the electrode region 11, while the edge region outside the electrode region 11 without the electrode structure 20 is the non-electrode region 12. After the insulating material solidifies and extends, the back-contact solar cell 100 still has an edge region uncontaminated by the first edge insulating block 30A, ensuring insulation effectiveness while improving the cell printing yield.

[0069] refer to Figure 5 and Figure 6 There are multiple electrode regions 11, and two adjacent electrode regions 11 are spaced apart in the second direction L2. The non-electrode region 12 is the edge region of the substrate 10 in the second direction L2 and / or the spacing region between two adjacent electrode regions 11 (i.e., the cutting path region).

[0070] In other words, when the entire back-contact solar cell 100 needs to be cut into multiple pieces, the back-contact solar cell 100 has an edge area and a spacing area (i.e., a cutting line area) located between two adjacent electrode areas 11 before cutting, and cutting can be performed on the cutting line area between two adjacent electrode areas 11.

[0071] It is understandable that if the cutting path area is covered by the extended insulating rubber block, it will cause thickness changes, thereby affecting the battery cutting and causing an increase in the fragmentation rate. Therefore, the present application sets a first edge insulating block 30A on the electrode structure 20 adjacent to the cutting path area, so that the width of the first edge insulating block 30A on both sides of the electrode structure 20 is different, and the width of the first edge insulating block 30A on the side close to the cutting path area is relatively small, and the width of the first edge insulating block 30A on the side away from the cutting path area is relatively large. The first edge insulating block 30A ensures the insulation effect while also ensuring that the first edge insulating block 30A will not occupy the cutting path area. This not only reduces the amount of insulating material used to improve the warping problem of the battery, but also avoids process problems such as poor slicing.

[0072] In some optional embodiments, when the non-electrode region 12 is an edge region of the substrate 10, the ratio of the first spacing d1 to the second spacing d2 is 0.17 to 0.87. For example, the ratio of the first spacing d1 to the second spacing d2 can be 0.17, 0.20, 0.27, 0.30, 0.37, 0.40, 0.47, 0.50, 0.57, 0.67, 0.77, 0.87, etc. When the non-electrode region 12 is a spacing region between two adjacent electrode regions 11, the ratio of the first spacing d1 to the second spacing d2 is 0.17 to 0.55. For example, the ratio of the first spacing d1 to the second spacing d2 can be 0.17, 0.20, 0.22, 0.25, 0.27, 0.30, 0.37, 0.40, 0.47, 0.50, 0.52, 0.55, etc.

[0073] If the ratio between the first spacing d1 and the second spacing d2 is too small, the width of the first edge insulating block 30A on the side of the electrode structure 20 near the non-electrode area 12 is too small. At this time, its attachment area on the substrate 10 is too small, and the fixing effect is poor, which can easily cause the first edge insulating block 30A to peel off from the electrode structure 20. If the ratio between the first spacing d1 and the second spacing d2 is too large, the width of the first edge insulating block 30A on the side of the electrode structure 20 near the non-electrode area 12 is too large. At this time, its attachment area on the substrate 10 is too large, resulting in the substrate 10 being dirty after the insulating material is coated, which is not conducive to improving the battery printing yield and causing process problems such as poor slicing after slicing. Therefore, making the ratio between the first spacing d1 and the second spacing d2 reach any value within the above range can ensure that the first edge insulating block 30A has sufficient insulation effect, thereby playing a role in protecting the opposite-sex electrode, and can also optimize the surface of the substrate 10, improve the battery printing yield, and avoid process problems such as poor slicing after slicing.

[0074] In some optional implementations, when the non-electrode area 12 is an edge area of ​​the substrate 10, the first spacing d1 is 0.08-0.4 mm. For example, the first spacing d1 can be 0.08 mm, 0.1 mm, 0.12 mm, 0.15 mm, 0.18 mm, 0.2 mm, 0.25 mm, 0.28 mm, 0.3 mm, 0.32 mm, 0.35 mm, 0.38 mm, 0.4 mm, etc. When the non-electrode area 12 is a spacing area between two adjacent electrode areas 11, the first spacing d1 is 0.08-0.25 mm. For example, the first spacing d1 can be 0.08 mm, 0.09 mm, 0.1 mm, 0.11 mm, 0.12 mm, 0.13 mm, 0.14 mm, 0.15 mm, 0.18 mm, 0.2 mm, 0.22 mm, 0.25 mm, etc.

[0075] By making the first distance d1 reach any value within the above range, it can be ensured that the first edge insulating block 30A will not exceed the non-electrode area 12 of the substrate 10, and the first edge insulating block 30A can sufficiently cover the portion of the substrate 10 located between the non-electrode area 12 and the electrode structure 20, ensuring that the first edge insulating block 30A has sufficient insulation effect.

[0076] In some optional implementations, when the non-electrode area 12 is an edge area of ​​the substrate 10, the second spacing d2 is 0.081-0.46 mm. For example, the second spacing d2 can be 0.081 mm, 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, 0.28 mm, 0.3 mm, 0.35 mm, 0.38 mm, 0.4 mm, 0.42 mm, 0.44 mm, 0.46 mm, etc. When the non-electrode area 12 is a spacing area between two adjacent electrode areas 11, the second spacing d2 is 0.081-0.46 mm. For example, the second spacing d2 can be 0.081 mm, 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, 0.28 mm, 0.3 mm, 0.35 mm, 0.38 mm, 0.4 mm, 0.42 mm, 0.44 mm, 0.46 mm, etc.

[0077] Such a configuration enables the first edge insulating block 30A to sufficiently cover the portion of the substrate 10 located between the electrode structure 20 and its adjacent opposite-sex electrode, thereby ensuring that the first edge insulating block 30A has sufficient insulating effect.

[0078] In some optional implementations, the width of the edge region of the substrate 10 in the second direction L2 is greater than 0.2 mm. In this case, if the non-electrode region 12 is the edge region of the substrate 10, the width of the edge region of the substrate 10 in the second direction L2 is the width D1 of the non-electrode region 12. Preferably, the width of the edge region of the substrate 10 in the second direction L2 is 0.28 mm.

[0079] In some optional implementations, the width of the spacing region (i.e., the scribe line region) between two adjacent electrode regions 11 in the second direction L2 is greater than 0.1 mm. In this case, if the non-electrode region 12 is the scribe line region of the substrate 10, the width of the scribe line region of the substrate 10 in the second direction L2 is equal to the width D1 of the non-electrode region 12. Preferably, the width of the scribe line region in the second direction L2 is 0.2 mm.

[0080] like Figure 3 and Figure 6As shown, within each electrode region 11, along the second direction L2 and in the direction from the non-electrode region 12 toward the electrode region 11, the lengths of the plurality of first insulating blocks 30 arranged continuously at the end portions are sequentially reduced. In this case, the end portions may be an end close to the non-electrode region 12 (corresponding to the end of the welding ribbon head) and / or an end away from the non-electrode region 12 (corresponding to the end of the welding ribbon tail) along the second direction L2 and in the direction from the non-electrode region 12 toward the electrode region 11. The plurality of first insulating blocks 30 arranged continuously at the end portions adopt a pyramidal layout, which can avoid short circuit problems caused by deviation of the welding ribbon head and / or the welding ribbon tail, and can also minimize the amount of insulating material used compared to an overall widening.

[0081] Exemplarily, in each electrode region 11, along the second direction L2 and in the direction from the non-electrode region 12 toward the electrode region 11, the lengths of the multiple first insulating blocks 30 continuously arranged near one end of the non-electrode region 12 are successively reduced to avoid the short circuit problem caused by the deviation of the welding strip head; or, the lengths of the multiple first insulating blocks 30 continuously arranged at one end away from the non-electrode region 12 are successively reduced to avoid the short circuit problem caused by the deviation of the welding strip tail; or, the lengths of the multiple first insulating blocks 30 continuously arranged near one end of the non-electrode region 12 and at one end away from the non-electrode region 12 are both successively reduced to avoid the short circuit problem caused by the deviation of the welding strip head and the welding strip tail at the same time.

[0082] The plurality of first insulating blocks 30 also includes a plurality of first central insulating blocks 30B and second edge insulating blocks 30C. The plurality of first central insulating blocks 30B are positioned between the first edge insulating blocks 30A and the second edge insulating blocks 30C in the second direction L2. The length difference between the first edge insulating blocks 30A and the second edge insulating blocks 30C is 2-4 mm. For example, the length difference between the first edge insulating blocks 30A and the second edge insulating blocks 30C can be 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, etc. This arrangement minimizes the amount of insulating material used, thereby improving battery warpage.

[0083] The photovoltaic module of the present application further includes an electrical connection wire (not shown, also referred to as a soldering ribbon), which is connected to the electrode structure 20 of a first polarity. The first insulating block 30 is located between the electrical connection wire and the electrode structure 20 of a second polarity, where the first polarity is opposite to the second polarity. Specifically, the electrical connection wire may be, but is not limited to, tinned copper strip, tin-coated copper strip, tinned aluminum strip, tin-coated aluminum strip, etc.

[0084] For example, in a cell string (comprising a plurality of back-contact solar cells 100), electrical connection wires are welded to the first polarity electrode structure 20 of the first cell and the second polarity electrode structure 20 of the second cell, and so on. Specifically, the first polarity electrode structure 20 can be a positive electrode structure, and the second polarity electrode structure 20 can be a negative electrode structure, or vice versa.

[0085] In this embodiment, the first insulating block 30 is located between the electrical connection line and the electrode structure 20 of the second polarity, that is, when the electrical connection line is connected to the positive electrode structure, the first insulating block 30 is provided at the position of the negative electrode structure that the electrical connection line crosses. One side surface of the first insulating block 30 is arranged to face the negative electrode structure and attached to the negative electrode structure, while the other side surface is arranged to face the electrical connection line and attached to the electrical connection line, so as to achieve electrical insulation between the electrical connection line and the negative electrode structure it crosses, thereby avoiding the short circuit problem caused by the offset of the welding strip during the series welding process, and at the same time avoiding direct contact between the welding strip and the electrode structure 20 of the same polarity, resulting in the risk of melting of the electrode structure 20.

[0086] To achieve connection between the electrical connection wires and the electrode structures 20, welding points (not shown) may be provided on the electrode structures 20. The electrical connection wires are connected to the plurality of electrode structures 20 via the welding points on the plurality of electrode structures 20, thereby achieving connection between the back-contact solar cell 100 and other back-contact solar cells 100. A plurality of first insulating blocks 30 are provided between adjacent welding points on the non-electrode regions 12.

[0087] refer to Figure 1 and Figure 2 The photovoltaic component also includes a bus electrode 200 extending along the second direction L2, the electrode structure 20 extending along the first direction L1, the bus electrode 200 is connected to the electrode structure 20 with the same polarity, and the bus electrode 200 is located between the electrical connection line and the first insulating block 30.

[0088] It is understandable that there may be multiple bus electrodes 200, each bus electrode 200 being used to connect to multiple electrode structures 20 of the same polarity to collect current collected by the multiple electrode structures 20 of the same polarity. Specifically, the multiple bus electrodes 200 include positive polarity bus electrodes 200 and negative polarity bus electrodes 200. The positive polarity bus electrodes 200 are connected to the multiple positive polarity electrode structures 20 to collect current collected by the multiple positive polarity electrode structures 20; the negative polarity bus electrodes 200 are used to connect to the multiple negative polarity electrode structures 20 to collect current collected by the multiple negative polarity electrode structures 20.

[0089] In this embodiment, the electrical connection wire is connected to the bus electrode 200 to achieve a connection between the back-contact solar cell 100 and other back-contact solar cells 100. For example, in a cell string, the electrical connection wire is connected to the positive bus electrode 200 of the first cell, and simultaneously connected to the negative bus electrode 200 of the second cell. The bus electrodes 200 are located between the electrical connection wire and the first insulating block 30. The first insulating block 30 provides electrical insulation between the electrical connection wire and the negative bus electrode 200 it crosses, thereby preventing short circuits caused by solder ribbon offset during the string soldering process and preventing the risk of the solder ribbon directly contacting the bus electrode 200 of the same polarity, which could cause the bus electrode 200 to melt.

[0090] To connect the electrical connection wires to the bus electrodes 200, the bus electrodes 200 are provided with a plurality of connection points P spaced apart. The electrical connection wires are connected to a plurality of bus electrodes 200 of the same polarity via the connection points P on the bus electrodes 200, thereby connecting the back-contact solar cell 100 to other back-contact solar cells 100. A plurality of first insulating blocks 30 are provided between the connection points P adjacent to the non-electrode region 12 and the non-electrode region 12.

[0091] Continue to refer Figure 1 and Figure 2 The widths of the bus electrode 200 at at least two locations along its extension direction are unequal. Preferably, the width of the bus electrode 200 along its extension direction is alternately increased and decreased, wherein the connection point P is provided at the widest portion of the bus electrode 200 along its extension direction.

[0092] Continue to refer Figure 1 and Figure 2 The back-contact solar cell 100 further includes a plurality of second insulating blocks 40 disposed between two adjacent connection points P. The plurality of second insulating blocks 40 are spaced apart, and an electrode structure 20 is provided between two adjacent second insulating blocks 40. Each second insulating block 40 can electrically isolate the electrical connection line from its corresponding opposite-sex electrode. Alternatively, the plurality of second insulating blocks 40 can be connected together in the direction in which the electrical connection line extends, i.e., the plurality of second insulating blocks 40 are continuously disposed without interruption, with only gaps at the connection between the electrical connection line and the electrode structure or bus electrode.

[0093] Continue to refer Figure 1 and Figure 2 The back-contact solar cell 100 further includes third insulating blocks 50 disposed on both sides of the connection point P, and the third insulating blocks 50 on both sides of the connection point P are symmetrically arranged, thereby electrically isolating the opposite-polarity electrodes on both sides of the electrical connection line.

[0094] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Those skilled in the art can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A back contact solar cell (100), characterized in that It comprises a substrate (10), an electrode structure (20) and a plurality of first insulating blocks (30); The electrode structure (20) is arranged on one side surface of the substrate (10), and the substrate (10) has an electrode area (11) where the electrode structure (20) is arranged and a non-electrode area (12) where the electrode structure (20) is not arranged; A plurality of first insulating blocks (30) are attached to the corresponding electrode structures (20), and the plurality of first insulating blocks (30) include a first edge insulating block (30A) adjacent to the non-electrode region (12), the first edge insulating block (30A) having a first edge (31) close to the non-electrode region (12) and a second edge (32) away from the non-electrode region (12); A first distance d1 between the center of the electrode structure (20) provided with the first edge insulating block (30A) and the first edge (31) is smaller than a second distance d2 between the center of the electrode structure (20) and the second edge (32).

2. The back contact solar cell (100) according to claim 1, characterized in that There is one electrode region (11), and the non-electrode region (12) is an edge region of the substrate (10); or, There are multiple electrode regions (11), two adjacent electrode regions (11) are spaced apart in a second direction (L2), and the non-electrode region (12) is an edge region of the substrate (10) in the second direction (L2) and / or a spaced region between two adjacent electrode regions (11).

3. The back contact solar cell (100) according to claim 2, characterized in that When the non-electrode area (12) is an edge area of ​​the substrate (10), the ratio between the first distance d1 and the second distance d2 is 0.17 to 0.87; and / or When the non-electrode region (12) is a spacing region between two adjacent electrode regions (11), the ratio of the first spacing d1 to the second spacing d2 is 0.17 to 0.

55.

4. The back contact solar cell (100) according to claim 2, characterized in that When the non-electrode area (12) is an edge area of ​​the substrate (10), the first distance d1 is 0.08-0.4 mm, and the second distance d2 is 0.081-0.46 mm; and / or When the non-electrode region (12) is a spacing region between two adjacent electrode regions (11), the first spacing d1 is 0.08-0.25 mm, and the second spacing d2 is 0.081-0.46 mm.

5. The back-contact solar cell (100) according to any one of claims 1 to 4, characterized in that: The difference between the second distance d2 and the first distance d1 is greater than 0 and not greater than 0.38 mm; and / or The width of the first edge insulating block (30A) is W1, the distance between the first edge insulating block (30A) and the edge of the non-electrode region (12) away from the first edge insulating block (30A) is D1, and the ratio of D1 to W1 is 0.033-0.

067.

6. The back contact solar cell (100) according to claim 2, characterized in that In each of the electrode regions (11), along the second direction (L2) and in a direction from the non-electrode region (12) toward the electrode region (11), the lengths of the plurality of first insulating blocks (30) located at the end portions are sequentially reduced.

7. The back contact solar cell (100) according to claim 6, characterized in that The plurality of first insulating blocks (30) further comprise a plurality of first central insulating blocks (30B) and a second edge insulating block (30C), wherein the plurality of first central insulating blocks (30B) are located between the first edge insulating blocks (30A) and the second edge insulating blocks (30C) in the second direction (L2), and the length difference between the first edge insulating blocks (30A) and the second edge insulating blocks (30C) is 2-4 mm; and / or The width of the edge region of the substrate (10) in the second direction (L2) is greater than 0.2 mm; and / or The width of the spacing region between two adjacent electrode regions (11) in the second direction (L2) is greater than 0.1 mm.

8. A photovoltaic module, characterized in that: Comprising at least one back-contact solar cell (100) according to any one of claims 1 to 7.

9. The photovoltaic module according to claim 8, characterized in that: The photovoltaic assembly further comprises an electrical connection line connected to the electrode structure (20) of the first polarity; The first insulating block (30) is located between the electrical connection line and the electrode structure (20) of a second polarity, and the first polarity is opposite to the second polarity.

10. The photovoltaic module according to claim 9, characterized in that: The electrode structure (20) is extended along a first direction (L1), and the photovoltaic assembly further comprises a bus electrode (200) extended along a second direction (L2); The bus electrode (200) is connected to the electrode structure (20) with the same polarity, and the bus electrode (200) is located between the electrical connection line and the first insulating block (30).

11. The photovoltaic module according to claim 10, characterized in that: The bus electrode (200) is provided with a plurality of connection points (P) arranged at intervals, and a plurality of the first insulating blocks (30) are arranged between the connection points (P) adjacent to the non-electrode region (12) and the non-electrode region (12).

12. The photovoltaic module according to claim 11, characterized in that: The back-contact solar cell (100) further comprises a plurality of second insulating blocks (40) arranged between two adjacent connection points (P), the plurality of second insulating blocks (40) being arranged at intervals and the electrode structure (20) being provided between two adjacent second insulating blocks (40); and / or The back-contact solar cell (100) further comprises a plurality of second insulating blocks (40) arranged between two adjacent connection points (P), wherein the plurality of second insulating blocks (40) are connected into one body; and / or The widths of at least two positions of the bus electrode (200) in its extension direction are unequal; and / or The back-contact solar cell (100) further comprises third insulating blocks (50) arranged on both sides of the connection point (P), and the third insulating blocks (50) on both sides of the connection point (P) are symmetrically arranged.

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