Solar cell substrate intermediates, solar cells, photovoltaic modules
By setting recessed areas and flat surfaces on the intermediate body of the solar cell substrate, the problem of substrate fragility during rework is solved, the yield and light utilization rate are improved, and the performance of the solar cell is enhanced.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- TONGWEI SOLAR ENERGY (CHENGDU) CO LID
- Filing Date
- 2025-07-07
- Publication Date
- 2026-07-31
AI Technical Summary
During the rework process of solar cells, the substrate is prone to fragmentation and cracking, leading to a decrease in yield and productivity.
By using a non-flat surface with recessed areas as the light-receiving surface and a flatter surface as the backlighting surface as the substrate intermediate, and by controlling the height difference and micro-protrusion structure, etching precision is ensured, stress concentration is avoided, and the quality of the patterned structure is improved.
This improved the yield and productivity of solar cells, increased the light-receiving area, enhanced the utilization rate of sunlight, and improved the performance of solar cells.
Smart Images
Figure CN224583619U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of solar cell technology, and more particularly to solar cell substrate intermediates, solar cells, and photovoltaic modules. Background Technology
[0002] During the manufacturing process of solar cells, some defective cells will be selected and reworked to produce solar cells.
[0003] However, during the reprocessing of the substrate, especially when fabricating patterned structures, the substrate is more prone to problems such as fragmentation and cracking, which can affect the performance of the solar cell and reduce the yield and productivity of the solar cell. Utility Model Content
[0004] This utility model discloses a solar cell substrate intermediate, a solar cell, and a photovoltaic module. Using the silicon substrate of the reworked wafer described in this application effectively ensures its performance during the reprocessing process, contributing to improved solar cell performance, yield, and productivity.
[0005] In the first aspect, this application discloses a substrate intermediate for a solar cell, wherein the substrate intermediate is the substrate for a reworked solar cell, and the substrate intermediate includes a first surface and a second surface disposed opposite to each other.
[0006] Wherein, the first surface is a non-flat surface with a recessed area, the first surface includes a first surface and a second surface with a height difference, the position of the second surface corresponds to the recessed area; the second surface is a surface that is flatter than the first surface.
[0007] Wherein, the first surface serves as the light-receiving surface in the solar cell, and the second surface serves as the backlighting surface in the solar cell; the recessed region is a non-electrode region, and the area of the recessed region accounts for 50% to 80% of the area of the first surface.
[0008] Furthermore, along the thickness direction of the substrate intermediate, the height difference between the first surface and the second surface is 2.5 μm to 12 μm; and / or,
[0009] The distance between the highest and lowest points of the second surface is 0.2 μm to 2 μm.
[0010] Furthermore, the first surface has a plurality of first micro-protrusions, the second surface has a plurality of second micro-protrusions, and the second surface has a plurality of third micro-protrusions, wherein the first micro-protrusions, the second micro-protrusions, and the third micro-protrusions are each independently selected from a pyramid structure or a frustum structure.
[0011] Furthermore, the first micro-protrusion is a first frustum structure, the second micro-protrusion is a second frustum structure, and the average length of the diagonals of a plurality of the first frustum structures is greater than the average length of the diagonals of a plurality of the second frustum structures.
[0012] Further, along the thickness direction of the substrate intermediate, the orthographic projection width of any of the first surfaces is 100 μm to 900 μm; and / or,
[0013] Along the thickness direction of the substrate intermediate, the orthographic projection width of any of the second surfaces is 100 μm to 900 μm; and / or,
[0014] Along the direction from the first surface to the second surface, the cross-section of the recessed region has a structure that is wider at the top and narrower at the bottom, and the first surface and the second surface are connected together by an inclined surface; and / or,
[0015] The third micro-protrusion is a first pyramid structure.
[0016] Furthermore, in the battery rework sheet, the first side is configured as the backlight side of the battery rework sheet, and the second side is configured as the light-receiving side of the battery rework sheet; in the battery rework sheet, a patterned film layer is provided on the backlight side of the battery rework sheet.
[0017] Secondly, embodiments of this application disclose a solar cell, the solar cell comprising a substrate and a film layer disposed on the substrate, the substrate being processed by the substrate intermediate described in any of the first aspects.
[0018] Furthermore, in the solar cell, the back surface of the substrate is configured as a surface obtained by patterning the second surface, and the back surface of the substrate includes a third surface and a fourth surface having a height difference.
[0019] In the solar cell, the light-receiving surface of the substrate is configured as the surface obtained by texturing the first surface, and both the first surface and the second surface have a plurality of pyramid structures.
[0020] Furthermore, a plurality of second pyramid structures are provided on the first surface, and a plurality of third pyramid structures are provided on the second surface;
[0021] The second pyramid structure includes a number of second substructures disposed near the third pyramid structure, each of the second substructures including an inclined edge, the inclined edge of each of the second substructures extending obliquely to each of the third pyramid structure.
[0022] Further, the length of the inclined edge of any of the second substructures is 0.1 μm to 10 μm; and / or,
[0023] The inclined edge is the longest edge on the second substructure; and / or,
[0024] The length of the diagonal of the base of any of the second pyramid structures is 0.1 μm to 5 μm; and / or,
[0025] The length of the diagonal of the base of any of the third pyramid structures is 0.1 μm to 5 μm.
[0026] Furthermore, a first doped silicon layer and a first functional layer are sequentially disposed on the first surface and the second surface, and the solar cell further includes a first electrode, which passes through the first functional layer and makes ohmic contact with the first doped silicon layer;
[0027] The substrate has a recessed area on its back surface, and the position of the fourth surface corresponds to the position of the recessed area. A dielectric layer and a second doped silicon layer are sequentially disposed on the third surface. A second functional layer is disposed on both the second doped silicon layer on the third surface and the fourth surface. The solar cell also includes a second electrode, which passes through the second functional layer and makes ohmic contact with the second doped silicon layer.
[0028] The first functional layer and the second functional layer include a passivation layer and / or an anti-reflection layer; one of the first electrode and the second electrode is a positive electrode and the other is a negative electrode; one of the first doped silicon layer and the second doped silicon layer is of N-type conductivity and the other is of P-type conductivity.
[0029] Thirdly, embodiments of this application disclose a photovoltaic module, the photovoltaic module comprising: the solar cell described in any of the second aspects.
[0030] Compared with the prior art, the beneficial effects of this application are as follows:
[0031] This application provides a substrate intermediate for solar cells, solar cells, and photovoltaic modules. The silicon substrate using the rework wafers of this application can effectively ensure its performance during the reprocessing process, which helps to improve the performance, yield, and efficiency of solar cells.
[0032] Specifically, the substrate intermediate of this application is the substrate of the reworked solar cell, and the first surface of the substrate intermediate is a non-flat surface with a recessed area, while the second surface is a flatter surface compared to the first surface. Therefore, during the patterning structure fabrication process of the reworked solar cell, the first surface is used as the light-receiving surface of the solar cell, and the second surface is used as the backlight surface of the solar cell. Since the second surface is flatter than the first surface, it helps to ensure the accuracy of etching during the etching process. Furthermore, because the second surface is flatter, there will be no height difference caused by unevenness, which helps to avoid the risk of solar cell breakage or cracking, thereby improving the yield and productivity of the solar cell.
[0033] Furthermore, to further improve the light absorption effect of the light-receiving surface, the recessed area in this application is a non-electrode area. Therefore, by setting the area of the recessed area to account for 50% to 80% of the area of the first surface, it helps to significantly improve the utilization rate of sunlight and enhance the performance of the solar cell. Moreover, since there is a height difference between the second surface and the first surface in the first surface, and the position of the second surface corresponds to the position of the recessed area, the first and second surfaces form a stepped structure. The presence of this stepped structure exposes the sidewalls of the steps, thereby helping to increase the area of the light-receiving surface of the solar cell and further improving the utilization rate of sunlight. Attached Figure Description
[0034] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0035] Figure 1 This is a schematic diagram of the structure of the first type of substrate intermediate provided in the embodiments of this application;
[0036] Figure 2 This is a schematic diagram of the structure of the second type of substrate intermediate provided in the embodiments of this application;
[0037] Figure 3 This is a schematic diagram of the structure of the third type of substrate intermediate provided in the embodiments of this application;
[0038] Figure 4 This is a schematic diagram of the structure of the fourth type of substrate intermediate provided in the embodiments of this application;
[0039] Figure 5 yes Figure 1 A scanning electron microscope (SEM) schematic diagram of the first and second surfaces in the image;
[0040] Figure 6 This is a schematic diagram of the first frustum structure provided in the embodiments of this application;
[0041] Figure 7 This is a schematic diagram of the structure of the fifth type of substrate intermediate provided in the embodiments of this application;
[0042] Figure 8 This is a schematic diagram of the structure of the sixth type of substrate intermediate provided in the embodiments of this application;
[0043] Figure 9 yes Figure 1 Scanning electron microscope image of the tilted surface in the image;
[0044] Figure 10 This is a schematic diagram of the structure of the solar cell substrate provided in the embodiments of this application;
[0045] Figure 11 yes Figure 10 Scanning electron microscope images of the first and second surfaces in the image;
[0046] Figure 12 This is a schematic diagram of the structure of the solar cell provided in the embodiments of this application.
[0047] Icons: 1. Substrate intermediate; 11. First surface; 11a. Recessed area; 111. First surface; 1111. First pyramid structure; 112. Second surface; 1121. Second pyramid structure; 12. Second surface; 113. Inclined surface; 2. Substrate; 21. Light-receiving surface; 211. First surface; 2111. Second pyramid structure; 2111a. Inclined edge; 212. Second surface; 2121. Third pyramid structure; 22. Backlight surface; 221. Third surface; 222. Fourth surface; 3. First doped silicon layer; 4. First functional layer; 5. First electrode; 6. Dielectric layer; 7. Second doped silicon layer; 8. Second functional layer; 9. Second electrode. Detailed Implementation
[0048] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0049] In this invention, the terms "upper," "lower," "left," "right," "front," "rear," "top," "bottom," "inner," "outer," "middle," "vertical," "horizontal," "lateral," and "longitudinal" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for the purpose of better describing this invention and its embodiments, and are not intended to limit the indicated device, element, or component to having a specific orientation, or to be constructed and operated in a specific orientation.
[0050] Furthermore, in addition to indicating direction or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in some cases to indicate a certain dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this utility model according to the specific circumstances.
[0051] Furthermore, the terms "first," "second," etc., are primarily used to distinguish different devices, elements, or components (which may be the same or different in specific type and construction), and are not intended to indicate or imply the relative importance or quantity of the indicated devices, elements, or components. Unless otherwise stated, "a plurality of" means two or more.
[0052] The technical solution provided by this utility model will be further described below with reference to the embodiments and accompanying drawings.
[0053] In the process of fabricating solar cells with patterned structures, functional layers are deposited on the surface of the original silicon wafer. However, if the deposited film has quality problems such as poor thickness uniformity or low film density, it will accelerate the degradation of the solar cell's photoelectric performance. Therefore, before fabricating the electrode structure, these defective wafers need to be selected for rework. This process requires a film removal and cleaning process to peel off the film layer on the surface of the original silicon wafer, restoring it to a reprocessed state.
[0054] In the process of reprocessing these substrates, especially in the preparation of patterned structures, the surface of the substrate has concave areas due to the patterning process in the early stage. Therefore, if these areas are patterned again, it will be difficult to effectively guarantee the yield, quality and performance of the prepared solar cells.
[0055] This is because the secondary patterning process of the recessed area increases the difficulty of patterning and makes it difficult to effectively guarantee the quality of the patterned structure. On the other hand, the processing will further increase the depth of the recessed area, and the recessed area is more prone to stress concentration, making the substrate more prone to fragmentation and cracking, which will affect the performance of the solar cell and reduce the yield and productivity of the solar cell.
[0056] Based on the above problems, this application discloses a substrate intermediate for solar cells, a solar cell, and a photovoltaic module. Solar cells prepared using this substrate intermediate can effectively alleviate problems such as substrate fragmentation and cracking, thereby resulting in high yield, good quality, and high performance of the solar cells.
[0057] The first aspect, such as Figure 1 As shown, this application discloses a substrate intermediate 1 for a solar cell. The substrate intermediate 1 is the substrate 2 of a reworked cell. The substrate intermediate 1 includes a first surface 11 and a second surface 12 disposed opposite to each other.
[0058] The first surface 11 is a non-flat surface with a recessed region 11a. The first surface 11 includes a first surface 111 and a second surface 112 with a height difference. The position of the second surface 112 corresponds to the recessed region 11a. The second surface 12 is a flatter surface relative to the first surface 11.
[0059] In this solar cell, the first surface 11 serves as the light-receiving surface 21, and the second surface 12 serves as the backlight surface 22. The recessed region 11a is a non-electrode region, and the area of the recessed region 11a accounts for 50% to 80% of the area of the first surface 11.
[0060] Among them, substrate intermediate 1 refers to the defective products that are screened out during the initial preparation of solar cells, and whose surface film layer is removed by the film removal and cleaning process to restore them to a state that can be reprocessed; reworked cells refer to semi-finished products that need to be reprocessed in the production process due to substandard quality; and solar cells refer to the final products obtained after further processing of substrate intermediate 1.
[0061] Additionally, see the return Figure 1 The first surface 11 is a non-flat surface, and the second surface 12 is a flat surface. The difference between the first surface 11 and the second surface 12 is the degree of undulation of the micro-morphology. The first surface 11 has a greater concavity depth, that is, the height difference H1 between the lowest and highest points of the non-flat surface is more obvious. The second surface 12 is flatter than the first surface 11, and its surface undulation is smaller, that is, the height difference H2 between the lowest and highest points of the flat surface is smaller, which is closer to the setting of the "ideal plane".
[0062] The substrate intermediate 1 of this application serves as the substrate 2 for the reworked solar cell. The first surface 11 of the substrate intermediate 1 is a non-flat surface with a recessed region 11a, and the second surface 12 is a flatter surface than the first surface 11. Therefore, during the fabrication of the patterned structure of the reworked solar cell, the first surface 11 serves as the light-receiving surface 21 of the solar cell, and the second surface 12 serves as the backlight surface 22. Since the second surface 12 is flatter than the first surface 11, during the etching process, on the one hand, the etching process can be precisely controlled to ensure the quality of the resulting patterned structure; on the other hand, it can not only avoid the height difference caused by large surface unevenness but also effectively avoid stress concentration during the patterning process, thereby helping to avoid the risk of solar cell breakage and cracking, and improving the yield and productivity of the solar cell.
[0063] Furthermore, to further improve the light absorption effect of the light-receiving surface 21, the recessed region 11a of this application is a non-electrode region. Therefore, by setting the area of the recessed region 11a to account for 50% to 80% of the area of the first surface 11, it helps to improve the utilization rate of sunlight to a greater extent and improve the performance of the solar cell. Moreover, since there is a height difference between the second surface 112 and the first surface 111 in the first surface 11, and the position of the second surface 112 corresponds to the position of the recessed region 11a, the first surface 111 and the second surface 112 form a stepped structure. The existence of this stepped structure exposes the sidewalls of the steps, thereby increasing the area of the light-receiving surface 21 of the solar cell and further improving the utilization rate of sunlight.
[0064] In summary, the use of this substrate intermediate 1 can effectively ensure the quality of the patterned structure, which helps to improve the yield, efficiency, and performance of solar cells.
[0065] Furthermore, along the thickness direction of the substrate intermediate 1 (see...) Figure 1 In the Y direction (as shown in the diagram), the height difference H1 between the first surface 111 and the second surface 112 is 2.5 μm to 12 μm. Because of the height difference between the first surface 111 and the second surface 112, a stepped structure is formed. Therefore, by further controlling the height difference within the aforementioned range, it helps to increase the side surface area and further increase the utilization rate of sunlight by the solar cell. For example, the height difference is 2.5 μm, 5 μm, 7 μm, 9 μm, 12 μm, etc.
[0066] Furthermore, the distance H2 between the highest and lowest points of the second surface 12 is 0.2 μm to 2 μm. When the distance between the lowest and highest points of the second surface 12 is within the above range, compared with the height difference of 3 μm to 10 μm between the first surface 111 and the second surface 112, the surface flatness of the second surface 12 is higher, which is more conducive to the subsequent patterning fabrication process. For example, the distances are 0.2 μm, 1.05 μm, 1.1 μm, 1.15 μm, 2 μm, etc.
[0067] Furthermore, the first surface 111 has a plurality of first micro-protrusions, the second surface 112 has a plurality of second micro-protrusions, and the second surface 12 has a plurality of third micro-protrusions, wherein the first micro-protrusions, the second micro-protrusions, and the third micro-protrusions are each independently selected from a pyramid structure or a frustum structure.
[0068] In one alternative implementation, such as Figure 2 and Figure 3 As shown, the first, second, and third micro-protrusions have the same structure; that is, they are all either pyramidal or frustum-shaped structures. In a second optional embodiment, as... Figure 1 , Figure 4 The first, second, and third micro-protrusions have different structural designs. For example, the first and second micro-protrusions are both pyramidal structures, and the third micro-protrusion is a frustum structure; or, the second and third micro-protrusions are both pyramidal structures, and the first micro-protrusion is a frustum structure; or, the first and third micro-protrusions are both pyramidal structures, and the second micro-protrusion is a frustum structure; or, the first and second micro-protrusions are both frustum structures, and the third micro-protrusion is a pyramidal structure; or, the second and third micro-protrusions are both frustum structures, and the first micro-protrusion is a pyramidal structure; or, the second and third micro-protrusions are both frustum structures, and the second micro-protrusion is a pyramidal structure.
[0069] Among them, such as Figure 5 As shown, when the first micro-protrusion is a first frustum structure 1111 and the second micro-protrusion is a second frustum structure 1121, the average length of the diagonals of the plurality of first frustum structures 1111 is greater than the average length of the diagonals of the plurality of second frustum structures 1121.
[0070] The average length of the diagonals of a plurality of first frustum structures 1111 refers to the average value of the diagonals of all first frustum structures 1111 on the first surface 111; similarly, the average length of the diagonals of a plurality of second frustum structures 1121 has the same meaning. Wherein, as Figure 6As shown, the diagonal length of any first frustum structure 1111 refers to the average value of the two diagonals L1 and L2 in the first frustum structure 1111; similarly, the diagonal length of any second frustum structure 1121 has the same meaning.
[0071] When the average length of the diagonal of the first frustum structure 1111 is greater than that of the second frustum structure 1121, it indicates that the flatness of the first surface 111 is higher than that of the second surface 112. This helps to ensure the deposition effect of the subsequent functional layer, avoid the problem of film bursting, and thus make the functional layer have a better effect.
[0072] Furthermore, along the thickness direction of the substrate intermediate 1, the orthographic projection width of any first surface 111 is 100 μm to 900 μm. When the orthographic projection width of the first surface 111 is within the above range, it helps to ensure the effectiveness of electrode fabrication and reduces the difficulty of electrode fabrication. For example, the orthographic projection width of the first surface 111 is 100 μm, 300 μm, 500 μm, 700 μm, or 900 μm.
[0073] Furthermore, along the thickness direction of the intermediate body 1 of the substrate 2, the orthographic projection width L2 of any second surface 112 is 100 μm to 900 μm. When the orthographic projection width of the second surface 112 is within the above range, it can provide a sufficient light-receiving surface area 21, which helps to further improve the absorption and utilization rate of sunlight; and at this width, it also helps the subsequent texturing process, ensuring that the etching solution can effectively etch the second surface 112, thereby ensuring the effect of the pyramid structure obtained by the final fabrication of the solar cell. For example, the orthographic projection width of the second surface 112 is 100 μm, 300 μm, 500 μm, 700 μm, or 900 μm.
[0074] In the first alternative implementation, such as Figure 7 As shown, in the direction from the first surface 111 to the second surface 112 (see...) Figure 7 In the Y1 direction, the cross-section of the recessed region 11a is square or rectangular, such that the first surface 111 and the second surface 112 are connected by a vertically downward surface; in a second optional embodiment, such as Figure 8 As shown, along the direction from the first surface 111 to the second surface 112, the cross-section of the recessed region 11a has a structure that is narrower at the top and wider at the bottom, such that the first surface 111 and the second surface 112 are connected together by an inclined surface 113, and the inclined surface 113 is disposed downwards; in a third optional embodiment, such as Figure 1 and Figure 9As shown, along the direction from the first surface 111 to the second surface 112, the cross-section of the recessed region 11a has a structure that is wider at the top and narrower at the bottom. The first surface 111 and the second surface 112 are connected together by an inclined surface 113. The cross-section of the recessed region 11a having a structure that is wider at the top and narrower at the bottom means that the orthographic projection width of the recessed region 11a near the first surface 111 is greater than the width of the recessed region 11a near the second surface 112. In this design, the inclined surface 113 is set upwards, so that the inclined surface 113 can directly receive sunlight, thereby helping to further improve the absorption and utilization rate of sunlight.
[0075] Furthermore, in the battery rework sheet, the first side 11 is configured as the backlight side 22 of the battery rework sheet, and the second side 12 is configured as the light-receiving side 21 of the battery rework sheet; in the battery rework sheet, a patterned film layer is provided on the backlight side 22 of the battery rework sheet.
[0076] In the case of the battery rework sheet, the substrate of the battery rework sheet is inverted and is equivalent to the substrate intermediate 1. That is, the light-receiving surface of the battery rework sheet is the second surface 12 of the substrate intermediate 1, and the backlight surface of the battery rework sheet is the first surface 11 of the substrate intermediate 1.
[0077] Secondly, embodiments of this application disclose a solar cell, which includes a substrate 2 and a film layer disposed on the substrate 2. The substrate 2 is obtained by processing the substrate intermediate 1 of any of the first aspects.
[0078] Furthermore, in solar cells, see the reference... Figure 10 The backlight surface 22 of the substrate 2 is configured as a surface obtained by patterning the second surface 12, and the backlight surface 22 of the substrate 2 includes a third surface 221 and a fourth surface 222 having a height difference.
[0079] In the solar cell, the light-receiving surface 21 of the substrate 2 is configured as a surface obtained by texturing the first surface 11, and both the first surface 211 and the second surface 212 have several pyramid structures.
[0080] Patterning and texturing are both conventional technical operations in this field. By patterning the second surface 12 of the substrate intermediate 1, a back surface 22 of the solar cell with a patterned structure is formed. The position of the recessed area in the patterned structure corresponds to the fourth surface 222, thus making the third surface 221 and the fourth surface 222 have a height difference. By texturing the first surface 11 of the substrate intermediate 1, that is, by etching the first surface 11 of the substrate intermediate 1 with alkaline solution, it is made to exhibit anisotropic corrosion, so that the first surface 211 and the second surface 212 of the light-receiving surface 21 of the solar cell finally prepared both have several pyramid structures.
[0081] Furthermore, such as Figure 11 As shown, a plurality of second pyramid structures 2111 are provided on the first surface 211, and a plurality of third pyramid structures 2121 are provided on the second surface 212;
[0082] Among them, a plurality of second pyramid structures 2111 include a plurality of second substructures disposed near the third pyramid structure 2121, each of the second substructures including an inclined edge 2111a, the inclined edge 2111a of the second substructure extending obliquely to the third pyramid structure 2121.
[0083] At this point, the light-trapping effect of the second pyramid structure 2111 and the third pyramid structure 2121 can be effectively utilized to further improve the absorption and utilization rate of sunlight. Furthermore, since the inclined edge 2111a is a component of the second pyramid structure 2111, it also has a light-trapping effect, thereby further enhancing the absorption and utilization rate of sunlight.
[0084] Furthermore, the length of the inclined edge 2111a of any second substructure is 0.1 μm to 10 μm. When the length of the inclined edge 2111a of the second substructure is within the above range, it helps to further utilize its light-trapping effect and improve the absorption and utilization rate of sunlight to a greater extent. For example, the lengths are 0.1 μm, 2 μm, 4 μm, 6 μm, and 10 μm.
[0085] In addition, the inclined edge 2111a is the longest edge on the second substructure.
[0086] Furthermore, the length of the diagonal of the base of any second pyramid structure 2111 is 0.1 μm to 5 μm. The length of the diagonal of the base of any third pyramid structure 2121 is 0.1 μm to 5 μm. When the lengths of the diagonal of the base of the second pyramid structure 2111 and the third pyramid structure 2121 are within the above range, it indicates that the second pyramid structure 2111 and the third pyramid structure 2121 have better light-trapping effects.
[0087] In one alternative implementation, such as Figure 12 As shown, a first doped silicon layer 3 and a first functional layer 4 are sequentially disposed on the first surface 211 and the second surface 212. The solar cell also includes a first electrode 5, which passes through the first functional layer 4 and makes ohmic contact with the first doped silicon layer 3.
[0088] The backlight surface 22 of the substrate 2 has a recessed area, the position of the fourth surface 222 corresponds to the position of the recessed area, the third surface 221 is provided with a dielectric layer 6 and a second doped silicon layer 7 in sequence, the second doped silicon layer 7 on the third surface 221 and the fourth surface 222 are both provided with a second functional layer 8, the solar cell also includes a second electrode 9, the second electrode 9 passes through the second functional layer 8 and makes ohmic contact with the second doped silicon layer 7;
[0089] The first functional layer 4 and the second functional layer 8 include a passivation layer and / or an antireflection layer; one of the first electrode 5 and the second electrode 9 is a positive electrode and the other is a negative electrode; one of the first doped silicon layer 3 and the second doped silicon layer 7 is of N-type conductivity and the other is of P-type conductivity.
[0090] Thirdly, embodiments of this application disclose a photovoltaic module, which includes: a solar cell according to any one of the second aspects.
[0091] The above provides a detailed description of the solar cell substrate intermediate, solar cell, and photovoltaic module disclosed in the embodiments of this application. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the solar cell substrate intermediate, solar cell, and photovoltaic module. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this utility model. Therefore, the content of this specification should not be construed as a limitation of this utility model.
Claims
1. A substrate intermediate for a solar cell, characterized by, The substrate intermediate is the substrate of the battery rework sheet, and the substrate intermediate includes a first side and a second side disposed opposite to each other. Wherein, the first surface is a non-flat surface with a recessed area, the first surface includes a first surface and a second surface with a height difference, the position of the second surface corresponds to the recessed area; the second surface is a surface that is flatter than the first surface. Wherein, the first surface serves as the light-receiving surface in the solar cell, and the second surface serves as the backlighting surface in the solar cell; the recessed region is a non-electrode region, and the area of the recessed region accounts for 50% to 80% of the area of the first surface.
2. The substrate intermediate of claim 1, wherein, Along the thickness direction of the substrate intermediate, the height difference between the first surface and the second surface is 2.5 μm to 12 μm; and / or, The distance between the highest and lowest points of the second surface is 0.2 μm to 2 μm.
3. The substrate intermediate of claim 1, wherein, The first surface has a plurality of first micro-protrusions, the second surface has a plurality of second micro-protrusions, and the second surface has a plurality of third micro-protrusions, wherein the first micro-protrusions, the second micro-protrusions, and the third micro-protrusions are each independently selected from a pyramid structure or a frustum structure.
4. The substrate intermediate of claim 3, wherein, The first micro-protrusion is a first frustum structure, the second micro-protrusion is a second frustum structure, and the average length of the diagonals of a plurality of the first frustum structures is greater than the average length of the diagonals of a plurality of the second frustum structures.
5. The substrate intermediate according to any one of claims 1 to 4, characterized in that, Along the thickness direction of the substrate intermediate, the orthographic projection width of any of the first surfaces is 100μm~900μm; And / or, Along the thickness direction of the substrate intermediate, the orthographic projection width of any of the second surfaces is 100μm~900μm; And / or, Along the direction from the first surface to the second surface, the cross-section of the recessed region has a structure that is wider at the top and narrower at the bottom, and the first surface and the second surface are connected together by an inclined surface; and / or, The second surface has several third micro-protrusions, which are first pyramid structures.
6. The substrate intermediate according to any one of claims 1 to 4, characterized in that, In the battery rework sheet, the first side is configured as the backlight side of the battery rework sheet, and the second side is configured as the light-receiving side of the battery rework sheet; in the battery rework sheet, a patterned film layer is provided on the backlight side of the battery rework sheet.
7. A solar cell, characterized by The solar cell includes a substrate and a film layer disposed on the substrate, the substrate being obtained by processing a substrate intermediate as described in any one of claims 1 to 6.
8. The solar cell according to claim 7, characterized in that, In the solar cell, the back surface of the substrate is configured as a surface obtained by patterning the second surface, and the back surface of the substrate includes a third surface and a fourth surface having a height difference. In the solar cell, the light-receiving surface of the substrate is configured as the surface obtained by texturing the first surface, and both the first surface and the second surface have a plurality of pyramid structures.
9. The solar cell according to claim 8, characterized in that, A plurality of second pyramid structures are provided on the first surface, and a plurality of third pyramid structures are provided on the second surface; The second pyramid structure includes a number of second substructures disposed near the third pyramid structure, each of the second substructures including an inclined edge, the inclined edge of each of the second substructures extending obliquely to each of the third pyramid structure.
10. The solar cell according to claim 9, characterized in that, The length of the inclined edge of any of the second substructures is 0.1 μm to 10 μm; and / or, The inclined edge is the longest edge on the second substructure; and / or, The length of the diagonal of the base of any of the second pyramid structures is 0.1 μm to 5 μm; and / or, The length of the diagonal of the base of any of the third pyramid structures is 0.1 μm to 5 μm.
11. The solar cell according to any one of claims 8 to 10, characterized in that, A first doped silicon layer and a first functional layer are sequentially disposed on the first surface and the second surface. The solar cell also includes a first electrode, which passes through the first functional layer and makes ohmic contact with the first doped silicon layer. The substrate has a recessed area on its back surface, and the position of the fourth surface corresponds to the position of the recessed area. A dielectric layer and a second doped silicon layer are sequentially disposed on the third surface. A second functional layer is disposed on both the second doped silicon layer on the third surface and the fourth surface. The solar cell also includes a second electrode, which passes through the second functional layer and makes ohmic contact with the second doped silicon layer. The first functional layer and the second functional layer include a passivation layer and / or an anti-reflection layer; one of the first electrode and the second electrode is a positive electrode and the other is a negative electrode; one of the first doped silicon layer and the second doped silicon layer is of N-type conductivity and the other is of P-type conductivity.
12. A photovoltaic module, characterized by, The photovoltaic module includes: the solar cell according to any one of claims 7 to 11.