Laminated battery, battery assembly and photovoltaic system
By setting the thickness-controlled first light inlet layer and the second light inlet layer matching the refractive index in the light inlet layer of the stacked battery, the parasitic absorption problem of the transparent conductive oxide film in the stacked battery is solved, the long-wave spectral response and efficiency are improved, and the full-band light management effect is maintained.
Patent Information
- Application Number
- CN202422048372.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-22
- Publication Date
- 2025-06-24
- Estimated Expiration
- 2034-08-22
AI Technical Summary
Parasitic absorption of free carriers in the transparent conductive oxide film in the stacked battery in the long-wave range causes the long-wave spectral response and short-circuit current density of the bottom battery to be affected.
By providing the first and second incoming layers in the incoming layer of the stacked battery, the thickness of the first incoming layer is controlled between 5 nm and 60 nm, and the refractive index of the second incoming layer is basically equivalent to or between the refractive index of the first incoming layer and 1.65 of the first incoming layer, so as to reduce parasitic absorption and compensate for light refractive.
It effectively reduces the chance of parasitic absorption, improves the long-wave spectral response of the stacked battery, improves the efficiency of the stacked battery, and maintains good light management effect in the entire band range.
Smart Images
Figure CN223024887U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of solar cells, and particularly relates to a tandem cell, a cell module and a photovoltaic system. Background Art
[0002] At present, the highest efficiency reported for perovskite / Si solar cells has reached 33.9%, breaking through the efficiency limit of about 29% for traditional crystalline silicon solar cells, showing good application prospects. The structural complexity of tandem cells has been greatly improved, and there are more and more film layers, which will inevitably bring serious parasitic absorption problems. In particular, in current tandem cells, the electron transport layer side is generally used as the light-incident surface, and the most commonly used material on the surface is a transparent conductive oxide film represented by ITO. Its free carriers have obvious parasitic absorption in the long wavelength, which has a non-negligible impact on the long-wavelength spectral response of the bottom cell, and further affects the short-circuit current density of the tandem cell. Summary of the Utility Model
[0003] The purpose of the embodiments of the present application is to provide a tandem cell, a cell module and a photovoltaic system, which can improve the long-wavelength spectral response of the tandem cell and improve the efficiency of the tandem cell.
[0004] On the one hand, an embodiment of the present application provides a tandem cell, including a substrate structure layer, and a first light-incident layer and a second light-incident layer sequentially stacked on the substrate structure layer. The thickness of the first light-incident layer in the stacking direction is 5 nm to 60 nm, and the refractive index of the second light-incident layer is substantially equivalent to that of the first light-incident layer or between the refractive index of the first light-incident layer and 1.65.
[0005] Optionally, an n-type doped blocking layer is further provided between the substrate structure layer and the first light-incident layer.
[0006] Optionally, the first light-incident layer at least includes an ITO film layer, an IZO film layer, and an ICO film layer.
[0007] Optionally, the material of the second light-incident layer at least includes any one of AlOx, SiNx, ZnS, SiOx, Ta2O5, TiO2, ZnO, or a composite film formed by any combination thereof.
[0008] Optionally, the sum of the thicknesses of the first light-incident layer and the second light-incident layer in the stacking direction is between 20 nm and 100 nm.
[0009] Optionally, the n-type doped blocking layer includes ZnSnOx.
[0010] Optionally, it further includes an electrode layer disposed on the second light-incident layer. In the stacking direction, the electrode layer passes through the second light-incident layer and the first light-incident layer from above the second light-incident layer and extends to the junction of the first light-incident layer and the n-type doped blocking layer.
[0011] Optionally, the substrate structure layer includes a bottom cell, an ITO film layer, a hole transport layer, an absorption layer, and an electron transport layer stacked in sequence.
[0012] On the other hand, an embodiment of the present application provides a battery assembly including the above-mentioned stacked battery.
[0013] In still another aspect of the embodiments of the present application, a photovoltaic system is provided, including the above-mentioned battery assembly.
[0014] In the stacked battery, battery assembly, and photovoltaic system provided by the embodiments of the present application, when the thickness of the first light-incident layer in the stacking direction is reduced, the problem of parasitic absorption is reduced. At the same time, a second light-incident layer is disposed on the upper layer of the first light-incident layer, and the refractive index of the second light-incident layer is defined to be equivalent to that of the first light-incident layer or between the refractive index of the first light-incident layer and 1.65 to compensate for the problem of the degradation of the light management quality in the full wavelength range caused by the reduction of the thickness of the first light-incident layer. In this way, by reducing the thickness of the first light-incident layer, the probability of parasitic absorption is reduced, and by setting the second light-incident layer, the light refraction is compensated. After the thickness of the first light-incident layer with a high carrier concentration is effectively reduced, the probability of parasitic absorption is reduced, the long-wave spectral response of the stacked battery is improved, and thus the efficiency of the stacked battery is improved. Moreover, the good light management effect of the stacked battery in the full wavelength range is ensured to meet the overall performance. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] To more clearly illustrate the technical solutions of the embodiments of the present application, the following briefly introduces the drawings required to be used in the embodiments of the present application. It should be understood that the following drawings only show some embodiments of the present application and should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.
[0016] Figure 1 is a schematic structural diagram of the stacked battery provided in this embodiment;
[0017] Figure 2 is a schematic structural diagram of the prior art.
[0018] Icon: 100 - Substrate structure layer; 101 - Bottom cell; 102 - ITO film layer; 103 - Hole transport layer; 104 - Absorbing layer; 105 - Electron transport layer; 201 - Barrier layer; 202 - First light-incident layer; 203 - Second light-incident layer; 204 - Electrode layer. Detailed implementation manner
[0019] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application.
[0020] In the description of the present application, it should be noted that the orientation or positional relationship indicated by terms such as "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of this application is usually placed during use. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present application. In addition, terms such as "first", "second", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance.
[0021] It should also be noted that unless otherwise clearly specified and limited, the terms "set", "connect" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific situations.
[0022] Please refer to Figure 1 As shown, the embodiments of the present application provide a stacked battery, including: a substrate structure layer 100, and a first light-incident layer 202 and a second light-incident layer 203 that are sequentially stacked on the substrate structure layer 100. The thickness of the first light-incident layer 202 in the stacking direction is 5 nm to 60 nm, and the refractive index of the second light-incident layer 203 is basically equivalent to that of the first light-incident layer 202 or the refractive index of the second light-incident layer 203 is between the refractive index of the first light-incident layer and 1.65 (lower than the refractive index of the POE film).
[0023] In the example of the present application, the stacked battery is an inverted top battery, the electron transport layer (ETL) 105 is located on the absorption layer 104, the hole transport layer 103 is located below the absorption layer 104, the first light incident layer 202 and the second light incident layer 203 can be used as the light incident surface of the stacked battery, wherein the first light incident layer 202 includes an ITO film layer. Compared with the prior art, the thickness of the ITO film layer as the first light incident layer 202 in the stacking direction is reduced, thereby reducing the problem of parasitic absorption; at the same time, the second light incident layer 203 is arranged on the upper layer of the first light incident layer 202, and the refractive index of the second light incident layer 203 is limited to be equal to the refractive index of the first light incident layer 202 or between the refractive index of the first light incident layer and 1.65, so as to compensate for the ITO film layer. The problem of reduced light management quality in the full-band range caused by the reduction in TO film thickness is solved. In this way, the probability of parasitic absorption is reduced by reducing the thickness of the first light incident layer 202, and the light refraction is compensated by setting the second light incident layer 203, so that after the thickness of the first light incident layer 202 with high carrier concentration is effectively reduced, the parasitic absorption probability is reduced, the long-wave spectral response of the stacked battery is improved, and the efficiency of the stacked battery is improved; and the good light management effect of the stacked battery in the full-band range is guaranteed to meet the overall performance.
[0024] Of course, the present application does not limit the stacked battery to an inverted top battery. The stacked battery of the present application may also be an upright top battery, which is specifically configured according to actual needs.
[0025] Figure 2 The prior art is shown, and it can be seen that Figure 2 The thickness of the ITO in the top layer is relatively thick, which will cause serious parasitic absorption problems. The thickness of the first light incident layer 202 of the present application is significantly thicker than Figure 2 The smaller the thickness of the I TO, the less parasitic absorption can be achieved. However, since the thickness of the first light-entering layer 202 is reduced, although the parasitic absorption is reduced, the refraction of light when incident is also reduced, which is detrimental to the overall performance of the stacked battery. In order to compensate for the problem of light refraction, a second light-entering layer 203 is also provided.
[0026] For example, the second light incident layer 203 includes at least any one anti-reflection material of AlOx, SiNx, ZnS, SiOx, Ta2O5, TiO2, and ZnO, or a composite film formed by any of the above materials, for example, different oxides of aluminum and different nitrides of silicon, such as AlO, Al2O3, Si3N4, Si2N2, and SiN. Any material having a refractive index of about 2 (when the film thickness is 600 nm) can be used as the second light incident layer 203.
[0027] In the example of the present application, the sum of the thicknesses of the first light incident layer 202 and the second light incident layer 203 in the stacking direction is between 20 nm and 100 nm.Figure 2 In the prior art, for the top single-layer ITO film layer, the thickness of the first light-incident layer 202 should be less than that of the Figure 2 top ITO film layer in the prior art solution.
[0028] The first light-incident layer 202 is in direct contact with the second light-incident layer 203 and can be prepared by means such as masking, laser grooving, photolithography, etc.
[0029] Furthermore, an n-type doped blocking layer 201 is also provided between the substrate structure layer 100 and the first light-incident layer 202. Generally speaking, this n-type doped blocking layer 201 is SnOx, for example, it can be SnO, SnO2, etc. After n-type doping, ZnSnO, ZnSnO2 and other ZnSnOx can be prepared to improve the lateral carrier transport ability of SnOx. At the same time, according to the doping situation of the n-type doped blocking layer 201, the thickness of the upper first light-incident layer 202 can be thinned.
[0030] Exemplarily, the first light-incident layer 202 can be an ITO film layer, or an IZO film layer, an ICO film layer or other types of film layers.
[0031] It further includes an electrode layer 204. The electrode layer 204 is disposed on the second light-incident layer 203, and in the stacking direction, the electrode layer 204 passes through the second light-incident layer 203 and the first light-incident layer 202 from above the second light-incident layer 203 and extends to the junction of the first light-incident layer 202 and the n-type doped blocking layer 201, forming good contact with the surface of the n-type doped blocking layer 201. The electrode is electrically connected to an external device to apply the stacked battery to the required occasions.
[0032] For the substrate structure layer 100, it includes a bottom cell 101, an ITO film layer 102, a hole transport layer 103, an absorption layer 104 and an electron transport layer 105 stacked in sequence, and the n-type doped blocking layer 201 is located on the electron transport layer 105.
[0033] In one embodiment, the absorption layer 104 includes a perovskite absorption layer 104, the electron transport layer 105 includes a graphene layer, and the bottom cell 101 can be a crystalline silicon bottom cell 101 adapted to the upper structure.
[0034] Through the above settings, the selectivity of carriers at the interface of the absorption layer 104 / electron transport layer 105 can be reduced more effectively; Exemplarily, the electron transport layer 105 is C60, and the n-type doped blocking layer 201 can be ZnSnOx after doping. The existing Figure 2 C60 / SnOx contact is improved through n-type doping.
[0035] During specific application tests, the present application can be applied to the stacked battery under current mismatch conditions. According to the current adaptation characteristics of the sub-cells of the stacked battery, the open-circuit voltages of the sub-cells under different current conditions can be tested separately. However, the traditional testing method masks the influence of the sub-cell current mismatch on the I-V characteristics of the stacked battery.
[0036] On the other hand, an embodiment of the present application provides a battery assembly, including the above-mentioned stacked battery.
[0037] In yet another aspect of the embodiments of the present application, a photovoltaic system is provided, including the above-mentioned battery assembly.
[0038] The battery assembly and the photovoltaic system have the same structure and beneficial effects as the stacked battery in the foregoing embodiments. The structure and beneficial effects of the stacked battery have been described in detail in the foregoing embodiments and will not be elaborated herein.
[0039] The above are only the embodiments of the present application and are not intended to limit the protection scope of the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the protection scope of the present application.
Claims
1. A laminated battery, characterized in that: include: A base structure layer (100), and a first light incident layer (202) and a second light incident layer (203) sequentially stacked on the base structure layer (100), wherein the thickness of the first light incident layer (202) in the stacking direction is 5nm to 60nm, and the refractive index of the second light incident layer (203) is substantially equivalent to the refractive index of the first light incident layer (202) or is between the refractive index of the first light incident layer (202) and 1.
65.
2. The laminated battery according to claim 1, characterized in that: An n-type doped barrier layer (201) is also provided between the base structure layer (100) and the first light incident layer (202).
3. The laminated battery according to claim 1, characterized in that: The first light incident layer (202) comprises at least an ITO film layer, an IZO film layer, and an ICO film layer.
4. The laminated battery according to claim 1, characterized in that: The material of the second light incident layer (203) includes at least any one of AlOx, SiNx, ZnS, SiOx, Ta2O5, TiO2, and ZnO, or a composite film formed by any combination of these.
5. The laminated battery according to claim 1, characterized in that: The sum of the thicknesses of the first light incident layer (202) and the second light incident layer (203) in the stacking direction is between 20 nm and 100 nm.
6. The laminated battery according to claim 2, characterized in that: The n-type doped barrier layer (201) comprises ZnSnOx.
7. The laminated battery according to claim 2, characterized in that: The invention also comprises an electrode layer (204), wherein the electrode layer (204) is arranged on the second light incident layer (203), and in the stacking direction, the electrode layer (204) passes through the second light incident layer (203) and the first light incident layer (202) from above the second light incident layer (203), and extends to the junction between the first light incident layer (202) and the n-type doped blocking layer (201).
8. The laminated battery according to any one of claims 1 to 7, characterized in that: The base structure layer (100) comprises a bottom battery (101), an ITO film layer (102), a hole transport layer (103), an absorption layer (104) and an electron transport layer (105) which are stacked in sequence.
9. A battery assembly, characterized in that: A stacked battery comprising the layered battery according to any one of claims 1 to 8.
10. A photovoltaic system, characterized in that: A battery assembly comprising the battery assembly of claim 9.