Photovoltaic cell, photovoltaic cell assembly and electric equipment
By designing gradient-controlled N-type and P-type passivation contact layers in photovoltaic cells, the problem of incomplete passivation film coverage was solved, improving film performance and photovoltaic cell conversion efficiency.
Patent Information
- Application Number
- CN202422957328.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-28
- Publication Date
- 2025-11-04
- Estimated Expiration
- 2034-11-28
AI Technical Summary
Existing crystalline silicon solar cells have all their gates on the back side, resulting in incomplete passivation film coverage and reduced film performance.
The N-type and P-type passivation contact layers are designed with gradient control in the direction perpendicular to the thickness of the photovoltaic cell, so that the lateral dimension of the end away from the substrate is smaller than that of the end closer to the substrate, forming an inverted trapezoidal structure and improving the film coverage.
It improved the film coverage, enhanced film performance, and improved the conversion efficiency and product quality of photovoltaic cells.
Smart Images
Figure CN223515251U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of battery technology, and in particular to a photovoltaic cell, a photovoltaic cell module, and an electrical device. Background Technology
[0002] A solar cell is a device that directly converts light energy into electrical energy through the photoelectric effect or photochemical effect.
[0003] Currently, to further improve the conversion efficiency of crystalline silicon solar cells, common crystalline silicon solar cells place all metal gates on the back side, completely releasing the optical shading area on the front side, thereby improving the utilization rate of sunlight. However, since all the gates are on the back side, a series of alternating P-regions and N-regions need to be fabricated on the back side. Due to the certain thickness of the material in the P-region and N-region, there is a problem of incomplete coating coverage when depositing films on the above two layers, which can easily reduce the performance of the film. Utility Model Content
[0004] This application provides a photovoltaic cell, a photovoltaic cell module, and an electrical device that can improve the coverage of the film layer when it is installed, thereby improving the performance of the film layer.
[0005] A first aspect of this application provides a photovoltaic cell, comprising at least:
[0006] Substrate layer;
[0007] And a passivation contact layer; the passivation contact layer is stacked with the substrate layer;
[0008] The passivation contact layer includes: an N-type passivation contact layer and a P-type passivation contact layer spaced apart;
[0009] In the direction perpendicular to the thickness of the photovoltaic cell, the lateral dimension of at least one of the N-type passivation contact layer and the P-type passivation contact layer at the end away from the substrate is smaller than the lateral dimension at the end closer to the substrate.
[0010] This application embodiment designs the structure of the N-type passivation contact layer and the P-type passivation contact layer. Specifically, in the thickness direction perpendicular to the photovoltaic cell, the lateral dimension of at least one of the N-type passivation contact layer and the P-type passivation contact layer at the end away from the substrate is smaller than the lateral dimension at the end closer to the substrate. In other words, at least one of the N-type passivation contact layer and the P-type passivation contact layer is gradient-controlled in the thickness direction. In this way, when a film layer is set on the side of the passivation contact layer away from the substrate, the film layer coverage can be improved, thereby improving the performance of the film layer.
[0011] In one possible implementation, the size of at least one of the N-type passivation contact layer and the P-type passivation contact layer gradually decreases in the direction perpendicular to the thickness of the photovoltaic cell, from one end closer to the substrate to the other end farther from the substrate.
[0012] In one possible implementation, the N-type passivation contact layer has an inverted trapezoidal structure in the thickness direction perpendicular to the photovoltaic cell, from one end near the substrate to the other end away from the substrate.
[0013] And / or, from one end near the substrate to the other end away from the substrate, the P-type passivation contact layer has an inverted trapezoidal structure.
[0014] In one possible implementation, there is a gap between the adjacent N-type passivation contact layers and the P-type passivation contact layers;
[0015] The minimum spacing between adjacent N-type passivation contact layers and P-type passivation contact layers is greater than 0 and less than or equal to 100 μm.
[0016] In one possible implementation, the N-type passivation contact layer has an inverted trapezoidal structure, wherein the projection length of any side of the N-type passivation contact layer onto the substrate is less than 0.5 times the width of the end of the N-type passivation contact layer closest to the substrate, and is greater than or equal to 0.1 nm.
[0017] In one possible implementation, the P-type passivation contact layer has an inverted trapezoidal structure, and the projection length of any side of the P-type passivation contact layer onto the substrate is less than 0.5 times the width of the end of the P-type passivation contact layer closest to the substrate, and is greater than or equal to 0.1 nm.
[0018] In one possible implementation, the ratio of the width of the P-type passivation contact layer near the substrate to the width of the N-type passivation contact layer near the substrate is (1.1-4):1.
[0019] In one possible implementation, the resistivity of the P-type passivation contact layer is in the ratio of (1-4):1 to the resistivity of the N-type passivation contact layer.
[0020] In one possible implementation, the passivation contact layer has a dimension of 5nm-250nm in the thickness direction of the photovoltaic cell.
[0021] In one possible implementation, the size of the N-type passivation contact layer gradually decreases in the direction perpendicular to the thickness of the photovoltaic cell, from one end near the substrate to the other end away from the substrate.
[0022] Furthermore, in the direction perpendicular to the thickness of the photovoltaic cell, from the end closest to the substrate to the end furthest from the substrate, the size of the P-type passivation contact layer gradually decreases.
[0023] In one possible implementation, it further includes: a first passivation layer; the first passivation layer is located between the substrate layer and the passivation contact layer.
[0024] In one possible implementation, the first passivation layer has a dimension of 0.5 nm to 2 nm in the thickness direction of the photovoltaic cell.
[0025] In one possible implementation, it further includes: a second passivation layer; the second passivation layer is located on the side of the substrate layer opposite to the passivation contact layer.
[0026] In one possible implementation, the second passivation layer has a dimension of 1 nm to 50 nm in the thickness direction of the photovoltaic cell.
[0027] In one possible implementation, it further includes: a first anti-reflective layer; the first anti-reflective layer is located on the side of the second passivation layer opposite to the substrate layer.
[0028] In one possible implementation, the first antireflective layer has a dimension of 50nm-200nm in the thickness direction of the photovoltaic cell.
[0029] In one possible implementation, a second anti-reflective layer is also included; the second anti-reflective layer is located on the side of the passivated contact layer opposite to the first passivation layer.
[0030] In one possible implementation, the second antireflective layer has a dimension of 50nm-200nm in the thickness direction of the photovoltaic cell.
[0031] In one possible implementation, it further includes: multiple electrodes; the N-type passivation contact layer and the P-type passivation contact layer are each independently connected to the electrodes.
[0032] In one possible implementation, the number of N-type passivation contact layers is multiple, and the number of P-type passivation contact layers is multiple;
[0033] Multiple N-type passivated contact layers and multiple P-type passivated contact layers are arranged alternately at intervals.
[0034] A second aspect of this application provides a photovoltaic cell module, comprising at least a housing and any of the photovoltaic cells described above; the photovoltaic cells are located inside the housing.
[0035] The embodiments of this application can improve the performance of photovoltaic modules by setting the aforementioned photovoltaic cells in the photovoltaic cell module.
[0036] A third aspect of this application provides an electrical device comprising at least any of the photovoltaic cells or photovoltaic cell modules described above.
[0037] The embodiments of this application can improve the performance of electrical equipment by setting the above-mentioned photovoltaic cells or photovoltaic cell modules in the electrical equipment. Attached Figure Description
[0038] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0039] Figure 1 This is a schematic diagram of the structure of a photovoltaic cell in the prior art;
[0040] Figure 2 This is a schematic diagram of a photovoltaic cell provided in an embodiment of this application;
[0041] Figure 3 This is a schematic diagram of another structure of the photovoltaic cell provided in an embodiment of this application;
[0042] Figure 4 This is another structural schematic diagram of a photovoltaic cell provided in an embodiment of this application.
[0043] Figure label:
[0044] 100-Photovoltaic cells;
[0045] 110 - Substrate layer;
[0046] 120 - Passivation contact layer;
[0047] 121-N type passivation contact layer; 122-P type passivation contact layer;
[0048] The projection length of the hypotenuse of any side of the 1211-N type passivation contact layer onto the substrate layer;
[0049] The width of the 1212-N type passivation contact layer at the end closest to the substrate;
[0050] The projection length of the hypotenuse of any side of the 1221-P type passivation contact layer onto the substrate layer;
[0051] The width of the 1222-P type passivation contact layer at the end closest to the substrate;
[0052] 130 - First passivation layer;
[0053] 140 - Second passivation layer;
[0054] 150 - First anti-reflective layer;
[0055] 160 - Second anti-reflective layer;
[0056] 170-Electrode. Detailed Implementation
[0057] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.
[0058] In response to the increasingly serious energy crisis and environmental pollution, the development of clean solar energy has received widespread attention. As one of the ways to utilize solar energy, solar cells have naturally become a hot topic in the market.
[0059] Currently, crystalline silicon solar cells have the highest market share in the photovoltaic market. Among them, tunnel oxide passivated contact (TOPCon) solar cells are a new type of passivated contact solar cells based on the selective carrier principle. The photovoltaic cell is an N-type silicon substrate cell. An ultra-thin layer of silicon oxide is prepared on the back of the cell, and then a layer of doped polycrystalline silicon is deposited. The two together form a passivated contact structure, which effectively reduces surface recombination and metal contact recombination.
[0060] To further improve the conversion efficiency of solar cells, in recent years, back-contact interdigitated cells based on TOPCon technology have been considered an important next-generation efficiency improvement strategy. This structure places all metal grids on the back of the cell, helping to completely free up the optical shading area on the front, improving the utilization of sunlight, and achieving an absolute efficiency improvement of 0.5%-1%.
[0061] Figure 1 This is a schematic diagram of the structure of a photovoltaic cell in the prior art. See related technologies. Figure 1As shown, existing crystalline silicon solar cells have all their gates on the back side, requiring the fabrication of a series of alternating P-type and N-type passivation contact layers on the back side. Since the materials in these two regions of the P-type and N-type passivation contact layers have a certain thickness, there is a problem of incomplete coating coverage when covering the passivation film on the aforementioned P-type and N-type passivation contact layers, which can easily reduce the passivation performance of the passivation film.
[0062] To address the aforementioned problems, this application provides a novel photovoltaic cell and an electrical device incorporating the photovoltaic cell. Specifically, the photovoltaic cell includes a substrate layer and a passivation contact layer; the passivation contact layer is stacked with the substrate layer; the passivation contact layer includes: an N-type passivation contact layer and a P-type passivation contact layer spaced apart; in the direction perpendicular to the thickness of the photovoltaic cell, at least one of the N-type and P-type passivation contact layers has a smaller lateral dimension at the end furthest from the substrate layer than at the end closest to the substrate layer. The photovoltaic cell provided by this application can improve the film coverage during coating, thereby improving the performance of the film layer.
[0063] The photovoltaic cell, photovoltaic cell module, and electrical equipment having the photovoltaic cell provided in the embodiments of this application will be described in detail below with reference to the accompanying drawings.
[0064] Figure 2 This is a schematic diagram of a photovoltaic cell provided in an embodiment of this application. Figure 3 This is a schematic diagram of another structure of the photovoltaic cell provided in an embodiment of this application. Figure 4 This is another structural schematic diagram of a photovoltaic cell provided in an embodiment of this application.
[0065] Reference Figures 2 to 4 As shown in the embodiment of this application, the photovoltaic cell 100 may include a substrate layer 110 and a passivation contact layer 120, wherein the passivation contact layer 120 and the substrate layer 110 are stacked together.
[0066] It is understood that, in the embodiments of this application, the substrate layer 110 may be made of silicon.
[0067] Specifically, in the embodiments of this application, the passivation contact layer 120 may include: an N-type passivation contact layer 121 and a P-type passivation contact layer 122 disposed at intervals. In the thickness direction perpendicular to the photovoltaic cell 100, the lateral dimension of at least one of the N-type passivation contact layer 121 and the P-type passivation contact layer 122 at the end away from the substrate layer 110 is smaller than the lateral dimension at the end closer to the substrate layer 110.
[0068] In this embodiment, the passivation contact layer 120 may be configured in several ways, including but not limited to the following:
[0069] One possible implementation is as follows: Figure 2 As shown, in the direction perpendicular to the thickness of the photovoltaic cell 100, the lateral dimensions of the N-type passivation contact layer 121 and the P-type passivation contact layer 122 at the ends away from the substrate layer 110 are both smaller than the lateral dimensions at the ends closer to the substrate layer 110.
[0070] Another possible implementation is: Figure 3 As shown, in the thickness direction perpendicular to the photovoltaic cell 100, the lateral dimension of the N-type passivation contact layer 121 at the end away from the substrate layer 110 is smaller than the lateral dimension at the end closer to the substrate layer 110.
[0071] Another possible implementation is: Figure 4 As shown, in the thickness direction perpendicular to the photovoltaic cell 100, the lateral dimension of the end of the P-type passivation contact layer 122 away from the substrate layer 110 is smaller than the lateral dimension of the end closer to the substrate layer 110.
[0072] By designing the structure of the N-type passivation contact layer and the P-type passivation contact layer, specifically, in the thickness direction perpendicular to the photovoltaic cell, the lateral dimension of at least one of the N-type passivation contact layer and the P-type passivation contact layer at the end away from the substrate is smaller than the lateral dimension of the end closer to the substrate. In other words, at least one of the N-type passivation contact layer and the P-type passivation contact layer is gradient-controlled in the thickness direction. In this way, when a film layer is set on the side of the passivation contact layer away from the substrate, the film layer coverage can be improved, thereby improving the performance of the film layer.
[0073] Specifically, in some embodiments, in the direction perpendicular to the thickness of the photovoltaic cell 100, from one end near the substrate layer 110 to the end away from the substrate layer 110, the size of at least one of the N-type passivation contact layer 121 and the P-type passivation contact layer 122 gradually decreases.
[0074] Specifically, in this case, the passivation contact layer 120 can be configured in several ways, including but not limited to the following:
[0075] One possible implementation is as follows: Figure 2 As shown, in the direction perpendicular to the thickness of the photovoltaic cell 100, from the end near the substrate 110 to the end away from the substrate 110, the dimensions of both the N-type passivation contact layer 121 and the P-type passivation contact layer 122 gradually decrease.
[0076] Another possible implementation is: Figure 3 As shown, in the direction perpendicular to the thickness of the photovoltaic cell 100, from the end near the substrate 110 to the end away from the substrate 110, the size of the N-type passivation contact layer 121 gradually decreases.
[0077] Another possible implementation is: Figure 4 As shown, in the direction perpendicular to the thickness of the photovoltaic cell 100, from the end near the substrate 110 to the end away from the substrate 110, the size of the P-type passivation contact layer 122 gradually decreases.
[0078] By designing the structure of the N-type passivation contact layer 121 and the P-type passivation contact layer 122, specifically, the size of at least one of the N-type passivation contact layer 121 and the P-type passivation contact layer 122 gradually decreases from the end near the substrate layer 110 to the end away from the substrate layer 110. In other words, the thickness of at least one of the N-type passivation contact layer 121 and the P-type passivation contact layer 122 is gradient controlled. In this way, when a film layer is provided on the side of the passivation contact layer 120 away from the substrate layer 110, the film coverage can be improved, thereby improving the performance of the film layer.
[0079] In addition, by gradient-controlling at least one of the N-type passivation contact layer 121 and the P-type passivation contact layer 122 in the thickness direction, when a film layer is provided on the side of the passivation contact layer 120 facing away from the substrate layer 110, it is also possible to prevent the non-covered areas of the N-type passivation contact layer 121 and the P-type passivation contact layer 122 from being exposed to the external environment, and to prevent the N-type passivation contact layer 121 and the P-type passivation contact layer 122 from being contaminated by the outside environment during subsequent processes and use, thereby reducing product quality.
[0080] Specifically, see Figure 2 and Figure 3 As shown in the embodiments of this application, the N-type passivation contact layer 121 can have an inverted trapezoidal structure from one end near the substrate layer 110 to the other end away from the substrate layer 110.
[0081] In this embodiment, the projection length 1211 of any side of the N-type passivation contact layer 121 onto the substrate can be less than 0.5 times the width 1212 of the end of the N-type passivation contact layer near the substrate, and greater than or equal to 0.1 nm.
[0082] For example, the projection length 1211 of any side of the N-type passivation contact layer on the substrate can be 0.1nm, 0.11nm, 0.12nm, 0.13nm, 0.14nm, 0.15nm, etc. The embodiments of this application do not limit this, nor are they limited to the above examples.
[0083] It should be noted that the numerical values and ranges involved in this application are approximate values. Due to the influence of the manufacturing process, there may be a certain range of errors, which can be considered negligible by those skilled in the art.
[0084] See Figure 2 and Figure 4 As shown, the P-type passivation contact layer 122 can have an inverted trapezoidal structure from one end near the substrate layer 110 to the other end away from the substrate layer 110.
[0085] In the embodiments of this application, the projection length 1221 of any side of the P-type passivation contact layer onto the substrate layer can be less than 0.5 times the width 1222 of the end of the P-type passivation contact layer near the substrate layer, and greater than or equal to 0.1 nm.
[0086] For example, the projection length 1221 of any side of the P-type passivation contact layer on the substrate can be 0.1nm, 0.11nm, 0.12nm, 0.13nm, 0.14nm, 0.15nm, etc. The embodiments of this application do not limit this, nor are they limited to the above examples.
[0087] Additionally, it is understood that in the embodiments of this application, there may be a gap between adjacent N-type passivation contact layers 121 and P-type passivation contact layers 122.
[0088] In some embodiments, the minimum spacing between adjacent N-type passivation contact layers 121 and P-type passivation contact layers 122 can be greater than 0 and less than or equal to 100 μm. Exemplarily, the minimum spacing between adjacent N-type passivation contact layers 121 and P-type passivation contact layers 122 can be a range of 10 μm, 20 μm, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, or any combination thereof. This application embodiment does not limit this, nor is it limited to the above examples.
[0089] In this embodiment, the ratio of the width 1222 of the P-type passivation contact layer near the substrate to the width 1212 of the N-type passivation contact layer near the substrate can be (1.1-4):1. This facilitates the effective collection of electrons and holes in the photovoltaic cell 100, avoiding any impact on the collection capability of one or both electrons and holes.
[0090] For example, the ratio of the width 1222 of the P-type passivation contact layer near the substrate to the width 1212 of the N-type passivation contact layer near the substrate can be a range of 1.1:1, 1.5:1, 2:1, 2.5:1, 3:1, 3.5:1, 4:1 or any two of them. The embodiments of this application do not limit this, nor are they limited to the above examples.
[0091] In this embodiment, the resistivity ratio of the P-type passivation contact layer 122 to the N-type passivation contact layer 121 can be (1-4):1. This helps to adjust the difference in doping concentration between the P-type passivation contact layer 122 and the N-type passivation contact layer 121, as well as the mobility of electrons and holes.
[0092] For example, the ratio of the resistivity of the P-type passivation contact layer 122 to the resistivity of the N-type passivation contact layer 121 can be a range of 1:1, 2:1, 3:1, 4:1 or any two of them. The embodiments of this application do not limit this, nor are they limited to the above examples.
[0093] By quantitatively restricting the P-type passivation contact layer 122 and the N-type passivation contact layer 121 as described above, the effective separation and collection capabilities of electrons and holes can be improved, thereby increasing the conversion efficiency of the photovoltaic cell 100.
[0094] In this embodiment, the passivation contact layer 120 has a dimension of 5nm-250nm in the thickness direction of the photovoltaic cell 100.
[0095] In this embodiment, the passivation contact layer 120 can have a dimension of 5nm-250nm in the thickness direction of the photovoltaic cell 100. For example, the dimension of the passivation contact layer 120 in the thickness direction of the photovoltaic cell 100 can be a range of 5nm, 50nm, 100nm, 150nm, 200nm, 250nm, or any combination thereof. This embodiment does not limit this range, nor is it limited to the above example.
[0096] Additionally, it is understood that in this embodiment, the passivation contact layer 120 may further include an insulating portion (not shown in the figure), wherein the insulating portion is located between the N-type passivation contact layer 121 and the P-type passivation contact layer 122. The insulating portion serves as an insulator. Furthermore, filling the space between the N-type passivation contact layer 121 and the P-type passivation contact layer 122 with an insulating portion can also enhance the mechanical properties of the passivation contact layer 120.
[0097] It should be noted that the material used for the insulating part can be intrinsic silicon or the like, and the embodiments of this application do not limit this, nor are they limited to the examples mentioned above.
[0098] Of course, in some other embodiments, an insulating portion may not be provided between the N-type passivation contact layer 121 and the P-type passivation contact layer 122, that is, the passivation contact layer 120 only includes the N-type passivation contact layer 121 and the P-type passivation contact layer 122 spaced apart. In other words, there is a gap between adjacent N-type passivation contact layers 121 and P-type passivation contact layers 122. However, when subsequently providing the second anti-reflection layer 160, it is necessary to place the second anti-reflection layer 160 within the gap between the N-type passivation contact layer 121 and the P-type passivation contact layer 122, which makes the process relatively complex. In this embodiment, an insulating portion is provided between the N-type passivation contact layer 121 and the P-type passivation contact layer 122. When providing the second anti-reflection layer 160, it is only necessary to place the second anti-reflection layer 160 on one side of the passivation contact layer 120 and the insulating portion, making the process relatively simple.
[0099] See Figures 2 to 4 As shown in the embodiments of this application, the photovoltaic cell 100 may further include: a first passivation layer 130, wherein the first passivation layer 130 may be located between the substrate layer 110 and the passivation contact layer 120.
[0100] The material used for the first passivation layer 130 can be silicon dioxide or the like. This application does not limit this, nor is it limited to the above examples.
[0101] In this embodiment, the first passivation layer 130 can have a dimension of 0.5 nm to 2 nm in the thickness direction of the photovoltaic cell 100. If the thickness of the first passivation layer 130 is too thick, it may lead to the inability of charge carriers to transport.
[0102] For example, the dimension of the first passivation layer 130 in the thickness direction of the photovoltaic cell 100 can be in the range of 0.5nm, 1nm, 1.5nm, 2nm, or any combination thereof. The embodiments of this application do not limit this, nor are they limited to the above examples.
[0103] In this embodiment of the application, the photovoltaic cell 100 may further include a second passivation layer 140, wherein the second passivation layer 140 may be located on the side of the substrate layer 110 opposite to the passivation contact layer 120.
[0104] The material used for the second passivation layer 140 can be alumina or silicon dioxide, etc. The embodiments of this application do not limit this, nor are they limited to the above examples.
[0105] In this embodiment, the size of the second passivation layer 140 in the thickness direction of the photovoltaic cell 100 can be 1nm-50nm. Exemplarily, the size of the second passivation layer 140 in the thickness direction of the photovoltaic cell 100 can be a range of 1nm, 5nm, 10nm, 15nm, 20nm, 25nm, 30nm, 35nm, 40nm, 45nm, 50nm, or any combination thereof. This embodiment does not limit this range, nor is it limited to the above example.
[0106] Continue to refer to Figures 2 to 4 As shown in the embodiments of this application, the photovoltaic cell 100 may further include a first anti-reflection layer 150, wherein the first anti-reflection layer 150 may be located on the side of the second passivation layer 140 facing away from the substrate layer 110, and in this case, the second passivation layer 140 is located between the first anti-reflection layer 150 and the substrate layer 110. The first anti-reflection layer 150 can reduce reflection.
[0107] The material used for the first anti-reflective layer 150 can be silicon nitride or the like. This application does not limit this, nor is it limited to the above examples.
[0108] In this embodiment, the dimension of the first antireflective layer 150 in the thickness direction of the photovoltaic cell 100 can be 50nm-200nm. For example, the dimension of the first antireflective layer 150 in the thickness direction of the photovoltaic cell 100 can be a range of 50nm, 100nm, 150nm, 200nm, or any combination thereof. This embodiment does not limit this range, nor is it limited to the above example.
[0109] In this embodiment, the photovoltaic cell 100 may further include a second anti-reflection layer 160, wherein the second anti-reflection layer 160 may be located on the side of the passivation contact layer 120 opposite to the first passivation layer 130, and the passivation contact layer 120 is located between the second anti-reflection layer 160 and the first passivation layer 130. The second anti-reflection layer 160 can reduce reflection.
[0110] In this embodiment, at least one of the N-type passivation contact layer 121 and the P-type passivation contact layer 122 is gradient-controlled in the thickness direction. Thus, taking the provision of the second anti-reflection layer 160 on the side of the passivation contact layer 120 facing away from the first passivation layer 130 as an example, the full coverage of the second anti-reflection layer 160 can be improved. The second anti-reflection layer 160 fully covers the side of the passivation contact layer 120 facing away from the first passivation layer 130, thereby improving the performance of the second anti-reflection layer 160.
[0111] The material used for the second anti-reflective layer 160 can be silicon nitride or the like. This application does not limit this to the above examples.
[0112] In this embodiment, the dimension of the second antireflective layer 160 in the thickness direction of the photovoltaic cell 100 can be 50nm-200nm. For example, the dimension of the second antireflective layer 160 in the thickness direction of the photovoltaic cell 100 can be a range of 50nm, 100nm, 150nm, 200nm, or any combination thereof. This embodiment does not limit this range, nor is it limited to the above example.
[0113] It should be noted that the specific thicknesses of the first anti-reflective layer 150 and the second anti-reflective layer 160 depend on the adjustment of the surface reflectivity.
[0114] In this embodiment of the application, the photovoltaic cell 100 may further include a plurality of electrodes 170, wherein an N-type passivation contact layer 121 and a P-type passivation contact layer 122 are each independently connected to the electrodes 170.
[0115] In one possible implementation, there can be multiple N-type passivation contact layers and multiple P-type passivation contact layers, with the multiple N-type passivation contact layers and multiple P-type passivation contact layers arranged alternately.
[0116] Examples of this application Figure 4 The photovoltaic cell 100 shown and the prior art Figure 1 The performance of the photovoltaic cell 100 shown was tested:
[0117] Under standard testing conditions, the atmospheric mass is 1.5 and the light intensity is 1000 W / m². 2 The temperature is 25℃. The following parameters are tested: open-circuit voltage, short-circuit current, fill factor, and conversion efficiency, to evaluate the performance of the solar cell.
[0118] Table 1
[0119]
[0120]
[0121] According to Table 1, it can be concluded that in the embodiments of this application... Figure 4 The photovoltaic cell 100 shown has a conversion efficiency greater than that of the prior art. Figure 1 The conversion efficiency of the photovoltaic cell 100 shown.
[0122] This application provides a method for preparing a photovoltaic cell 100, which specifically includes:
[0123] The substrate layer 110 is textured to form a pyramidal textured surface.
[0124] Texturing, as we can understand it, is a process for treating solar-grade silicon wafers. Generally, alkaline treatment is used to obtain a pyramidal textured surface, while acid treatment is used to obtain a wormhole-like textured surface. Both pyramidal and wormhole-like textures can improve the light-trapping effect of the silicon wafer.
[0125] A first passivation layer 130 is prepared on the back side of the aforementioned substrate layer 110. The thickness of the first passivation layer 130 can be 0.5 nm to 2 nm, and the material of the first passivation layer 130 can be silicon dioxide.
[0126] On the side of the first passivation layer 130 that faces away from the substrate layer 110, a P-type passivation contact layer 122 is formed. The thickness of the P-type passivation contact layer 122 can be 5 nm to 250 nm.
[0127] On the side of the P-type passivation contact layer 122 that is opposite to the first passivation layer 130, the mask layer (i.e., oxide layer) above the area corresponding to the subsequent N-type passivation contact layer 121 is selectively removed by laser grooving combined with patterning.
[0128] The above structure is chemically etched to remove the P-type passivation contact layer 122 in the trench area.
[0129] An N-type passivation contact layer 121 is formed on the side of the first passivation layer 130 that faces away from the substrate layer 110. The thickness of the N-type passivation contact layer 121 can be 5 nm to 250 nm.
[0130] On the side of the N-type passivation contact layer 121 that is opposite to the first passivation layer 130, the mask layer (i.e., oxide layer) above the P-type passivation contact layer 122 is selectively removed by laser grooving combined with patterning.
[0131] The above structure is chemically etched to remove the N-type passivation contact layer 121 in the trench area, and all mask layers are removed at the same time.
[0132] Using laser etching technology, a gap is created by etching the area where the N-type passivation contact layer 121 and the P-type passivation contact layer 122 are in contact. In addition, laser etching technology is used to etch different powers on both sides of the N-type passivation contact layer 121 and the P-type passivation contact layer 122 to create a gradient along the thickness direction.
[0133] A second passivation layer 140 is formed on the side of the substrate 110 opposite to the first passivation layer 130. The material of the second passivation layer 140 can be alumina or silicon dioxide, and the thickness of the second passivation layer 140 can be 1 nm to 50 nm.
[0134] A first anti-reflective layer 150 is formed on the side of the second passivation layer 140 that faces away from the substrate layer 110. The thickness of the first anti-reflective layer 150 can be 50 nm to 200 nm.
[0135] A second antireflective layer 160 is formed on the side of the first passivation layer 130 that faces away from the substrate layer 110. The thickness of the second antireflective layer 160 can be 50 nm to 200 nm.
[0136] The second antireflective layer 160 is screen-printed on the side facing away from the first passivation layer 130 to form the electrode 170.
[0137] This application embodiment also provides a photovoltaic cell module, which may include at least a housing and the aforementioned photovoltaic cell 100, wherein the photovoltaic cell 100 may be located inside the housing.
[0138] The embodiments of this application can improve the performance of photovoltaic modules by setting the photovoltaic cell 100 in the photovoltaic cell module.
[0139] In addition, this application embodiment also provides an electrical device, which may include at least the photovoltaic cell 100 or the photovoltaic cell module described above.
[0140] The electrical equipment in this application embodiment can be conventional electrical equipment in the art, such as power equipment (e.g., electric vehicles), electronic equipment (e.g., computers, mobile phones, digital cameras, printers, fax machines, etc.), wearable devices (e.g., watches, wristbands, VR glasses, etc.), and home appliances (e.g., air conditioners, refrigerators, washing machines, microwave ovens, etc.), etc., and there are no special limitations on this.
[0141] By incorporating the aforementioned photovoltaic cell 100 into the electrical equipment, the performance of the electrical equipment can be improved.
[0142] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.
[0143] In the description of this utility model, it should be understood that the terms "comprising" and "having" as used herein, and any variations thereof, are intended to cover non-exclusive inclusion, for example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such process, method, product, or device.
[0144] Unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal connection of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features.
[0145] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.
Claims
1. A photovoltaic cell, characterized in that, At least including: Substrate layer; and passivation contact layer; The passivation contact layer is stacked with the substrate layer; The passivation contact layer includes: an N-type passivation contact layer and a P-type passivation contact layer spaced apart; In the direction perpendicular to the thickness of the photovoltaic cell, the lateral dimension of at least one of the N-type passivation contact layer and the P-type passivation contact layer at the end away from the substrate is smaller than the lateral dimension at the end closer to the substrate.
2. The photovoltaic cell according to claim 1, characterized in that, In the direction perpendicular to the thickness of the photovoltaic cell, from the end closest to the substrate to the end furthest from the substrate, the size of at least one of the N-type passivation contact layer and the P-type passivation contact layer gradually decreases.
3. The photovoltaic cell according to claim 1, characterized in that, From one end near the substrate to the other end away from the substrate, the N-type passivation contact layer has an inverted trapezoidal structure; and / or, The P-type passivation contact layer has an inverted trapezoidal structure from one end near the substrate to the other end away from the substrate.
4. The photovoltaic cell according to claim 1, characterized in that, There is a gap between the adjacent N-type passivation contact layers and the P-type passivation contact layers; The minimum spacing between adjacent N-type passivation contact layers and P-type passivation contact layers is greater than 0 and less than or equal to 100 μm.
5. The photovoltaic cell according to claim 3, characterized in that, The N-type passivation contact layer has an inverted trapezoidal structure. The projection length of any side of the N-type passivation contact layer onto the substrate is less than 0.5 times the width of the end of the N-type passivation contact layer closest to the substrate, and is greater than or equal to 0.1 nm.
6. The photovoltaic cell according to claim 3, characterized in that, The P-type passivation contact layer has an inverted trapezoidal structure. The projection length of any side of the P-type passivation contact layer onto the substrate is less than 0.5 times the width of the end of the P-type passivation contact layer closest to the substrate, and is greater than or equal to 0.1 nm.
7. The photovoltaic cell according to any one of claims 1-6, characterized in that, The ratio of the width of the P-type passivation contact layer near the substrate to the width of the N-type passivation contact layer near the substrate is (1.1-4):
1.
8. The photovoltaic cell according to any one of claims 1-6, characterized in that, The resistivity ratio of the P-type passivation contact layer to the resistivity of the N-type passivation contact layer is (1-4):
1.
9. The photovoltaic cell according to any one of claims 1-6, characterized in that, The passivation contact layer has a dimension of 5nm-250nm in the thickness direction of the photovoltaic cell.
10. The photovoltaic cell according to any one of claims 1-6, characterized in that, In the direction perpendicular to the thickness of the photovoltaic cell, from one end closer to the substrate to the other end farther from the substrate, the size of the N-type passivation contact layer gradually decreases. Furthermore, in the direction perpendicular to the thickness of the photovoltaic cell, from the end closest to the substrate to the end furthest from the substrate, the size of the P-type passivation contact layer gradually decreases.
11. The photovoltaic cell according to any one of claims 1-6, characterized in that, Also includes: First passivation layer; The first passivation layer is located between the substrate layer and the passivation contact layer.
12. The photovoltaic cell according to claim 11, characterized in that, The first passivation layer has a dimension of 0.5nm-2nm in the thickness direction of the photovoltaic cell.
13. The photovoltaic cell according to any one of claims 1-6, characterized in that, Also includes: Second passivation layer; The second passivation layer is located on the side of the substrate layer opposite to the passivation contact layer.
14. The photovoltaic cell according to claim 13, characterized in that, The second passivation layer has a dimension of 1nm-50nm in the thickness direction of the photovoltaic cell.
15. The photovoltaic cell according to claim 13, characterized in that, Also includes: A first anti-reflective layer; the first anti-reflective layer is located on the side of the second passivation layer that faces away from the substrate layer.
16. The photovoltaic cell according to claim 15, characterized in that, The first anti-reflective layer has a dimension of 50nm-200nm in the thickness direction of the photovoltaic cell.
17. The photovoltaic cell according to claim 11, characterized in that, Also includes: The second anti-reflective layer is located on the side of the passivated contact layer that is opposite to the first passivation layer.
18. The photovoltaic cell according to claim 17, characterized in that, The second anti-reflective layer has a dimension of 50nm-200nm in the thickness direction of the photovoltaic cell.
19. The photovoltaic cell according to any one of claims 1-6, characterized in that, Also includes: Multiple electrodes; The N-type passivation contact layer and the P-type passivation contact layer are each independently connected to the electrode.
20. The photovoltaic cell according to claim 19, characterized in that, The number of N-type passivation contact layers is multiple, and the number of P-type passivation contact layers is multiple; Multiple N-type passivated contact layers and multiple P-type passivated contact layers are arranged alternately at intervals.
21. A photovoltaic cell module, characterized in that, include: The housing and the photovoltaic cell according to any one of claims 1-20; the photovoltaic cell is located inside the housing.
22. An electrical appliance, characterized in that, It includes at least the photovoltaic cell as described in any one of claims 1-20 or the photovoltaic cell module as described in claim 21.