A parallel-connected perovskite solar module

Abstract

The present invention discloses a parallel-connected perovskite solar module, which includes a number of active battery units and a number of double-wing structure metal grid units, specifically including: a transparent substrate, a transparent conductive thin film, a charge contact layer, a light absorption layer, a charge contact layer, a metal electrode, and a metal grid. The present invention creatively adopts a three-step selective etching process to form a double-wing structure metal grid for a parallel-connected perovskite module. The unique design of the double-wing structure metal grid can not only greatly simplify the processing flow of the parallel-connected perovskite solar module and reduce the production cost, but also significantly reduce the dead area of the metal grid and improve the effective light capture of the module to convert into more electric energy. At the same time, the etching process mentioned in this patent can be highly compatible with the existing industrial manufacturing equipment of solar modules, facilitating large-scale continuous production.

Description

Technical Field

[0001] The present invention relates to a solar cell, and particularly to a parallel-connected perovskite solar module. Background Art

[0002] A solar cell is a device that directly converts sunlight into electrical energy, involving three mechanisms for converting light into electricity: the photovoltaic effect, photoconductivity, and the bulk photovoltaic effect (or drift current effect). Among them, the photovoltaic effect usually requires a PN junction, where photo-generated charges (electrons and holes) are separated and transported in p-type and n-type materials and then collected at the electrodes to generate a photocurrent. In fact, without a PN junction, the conductivity of a semiconductor continuously increases with illumination because the number of free electrons increases, which is photoconductivity. However, due to the absence of a photovoltage, a simple change in photoconductivity cannot generate electricity. The third mechanism is the bulk photovoltaic effect that generates electrical energy in non-centrosymmetric materials without a PN junction. Regardless of the power generation mechanism, the selection of photovoltaic materials and the understanding of their intrinsic optoelectronic properties are crucial for achieving high photoelectric conversion efficiency. Generally, photovoltaic materials with a direct bandgap and a high absorption coefficient are suitable for high photoelectric conversion. From a materials engineering perspective, defect-free materials are ideal because they can minimize the power loss caused by non-radiative recombination.

[0003] Organic-inorganic hybrid lead halide perovskites are regarded as one of the ideal photovoltaic materials, with a certified power conversion efficiency reaching 25.2%, far exceeding existing high-efficiency thin-film solar cells such as CIGS or CdTe. In the past few years, significant breakthroughs have also been made in the stability of perovskite solar cells, which can withstand continuous light aging at 60 °C for more than 1000 hours without encapsulation. Therefore, perovskite solar technology already meets the requirements for commercialization, and the development of large-area perovskite solar modules is imminent. Summary of the Invention

[0004] The object of the present invention is to overcome the deficiencies in existing solar products, namely the lack of parallel modules and the lack of large-current low-voltage products, and to provide a parallel-connected perovskite solar module, which is particularly suitable for large-current low-voltage power generation scenarios such as BIPV.

[0005] To achieve the above object, the present invention is realized through the following technical solutions:

[0006] A parallel-connected perovskite solar module, comprising a plurality of active battery units and a plurality of double-wing structure metal grid units, which successively include a transparent substrate, a transparent conductive thin film, a first charge contact layer, a light-absorbing layer, a second charge contact layer, and a metal electrode from bottom to top. It also includes seven components: metal grid lines. Among them, the battery unit includes a transparent conductive thin film, a first charge contact layer, a light-absorbing layer, a second charge contact layer, and a metal electrode, which are responsible for converting solar energy into electrical energy. The grid line unit includes a metal grid line connected to the battery unit and ultra-small dead zones (i.e., double wings) etched and remaining on both sides of the grid line. The metal grid line is located between the battery units and is responsible for quickly extracting the electrical energy generated by the battery units to the external circuit. The active battery units are connected to the double-wing structure metal grid units through the transparent conductive thin film.

[0007] The transparent substrate includes rigid or flexible light-transmitting substrates such as glass, plastic, and mica sheets.

[0008] The light-absorbing layer is an MQZ3 type perovskite material, where M is at least one of Na + , Rb + , Cs + , Cu + , CH3NH3 + , CH(NH2)2 + , CH3(CH2)3NH3 + , and Q is at least one of Pb 2+ , Sn 2+ , and Z is at least one of Br - , I - , Cl - .

[0009] The relationship between the first charge contact layer and the second charge contact layer is that if one is an n-type semiconductor material such as TiO2, C60, ZnO, etc., the other will automatically be a p-type semiconductor material such as NiOx, CuGaO2, PTAA, P3HT, etc.

[0010] The metal electrode and the metal grid line are one or more metal alloys of gold, silver, copper, aluminum, nickel, molybdenum, antimony, chromium, bismuth, palladium, and titanium.

[0011] The transparent conductive thin film is FTO, ITO, IGZO, IWO, IZO, or AZO.

[0012] The present invention also provides a method for preparing a parallel-connected perovskite solar module, which is characterized by comprising the following steps: a) etching a transparent substrate with a transparent conductive film by P1, and then cleaning it and reserving it for use; b) sequentially depositing a first charge contact layer, a light-absorbing layer, and a second charge contact layer on the etched clean substrate; c) etching the substrate with the first charge contact layer, the light-absorbing layer, and the second charge contact layer by P2 to form a plurality of grid line filling areas; d) simultaneously depositing a metal electrode and a metal grid line on the etched substrate, and depositing the metal grid line in the grid line filling areas; e) etching the substrate covered with the metal by P3 to separate the battery unit and the grid line unit to form a double-wing structure metal grid line, and then connecting the wires to obtain the parallel-connected perovskite solar module.

[0013] The P1, P2, and P3 etching methods are laser etching or mechanical etching.

[0014] The width of the P1 etching is 0.03 μm to 1 cm, the width of the P2 etching is 0.03 μm to 10 cm, the width of the P3 etching is 0.03 μm to 1 cm, and the dead zone width is 0.01 μm to 100 μm.

[0015] The thickness of the metal grid line is 0.03 μm to 500 μm.

[0016] The beneficial effects of the present invention are as follows:

[0017] 1. The parallel-connected perovskite solar module prepared by the present invention exhibits better system robustness. If a sub-battery in the module is damaged and does not generate current, the module can still work.

[0018] 2. The parallel-connected perovskite solar module prepared by the present invention exhibits a higher GFF (geometric fill factor) because the metal grid line part can be optimized to a smaller proportion (<2 - 5%).

[0019] 3. The parallel-connected perovskite solar module prepared by the present invention shows low voltage and large current output characteristics, and is particularly suitable for application scenarios such as BIPV, which can ensure personnel safety.

[0020] 4. The parallel-connected perovskite solar module prepared by the present invention has higher operation stability. Since each sub-battery unit is independent of each other, the current generated by each sub-battery is only extracted and transmitted through the adjacent metal grid line, excluding the adverse interference between sub-batteries.

[0021] 5. The present invention uses an improved P1, P2, and P3 etching process to prepare a parallel-connected perovskite solar module, which not only greatly simplifies the processing steps, sharply reduces the production cost, but also better meets the requirements of large-scale continuous production.

[0022] 6. The present invention adopts a double-wing structure metal grid line, which is very convenient to process. The dead area of the metal grid line between each sub-cell is greatly reduced, and at the same time, the adverse contact problem between the metal grid line and the sub-cell unit is effectively overcome. Description of the Drawings

[0023] Figure 1 It is a schematic structural diagram of a parallel-connected perovskite solar module;

[0024] Figure 2 It is a schematic diagram of a preparation method of a parallel-connected perovskite solar module; Detailed Embodiments

[0025] The technical solutions of the present invention will be further described below in conjunction with the drawings in the specification:

[0026] As Figure 1 shown, a parallel-connected perovskite solar module includes a plurality of active cell units and a plurality of double-wing structure metal grid line units, which sequentially include a transparent substrate 1, a transparent conductive film 2, a charge contact layer 1 3, a light absorption layer 4, a charge contact layer 2 5, and a metal electrode 6 from bottom to top, and also includes seven components of a metal grid line 6'. Among them, the cell unit includes five parts: a transparent conductive film 2, a charge contact layer 1 3, a light absorption layer 4, a charge contact layer 2 5, and a metal electrode 6, which are responsible for converting solar energy into electrical energy. The grid line unit includes a metal grid line 6' connected to the cell unit and ultra-small dead zones etched and remaining on both sides of the grid line, namely double wings. The metal grid line 6' is located between the cell units and is responsible for quickly extracting the electrical energy generated by the cell units to the external circuit. The active cell unit is connected to the double-wing structure metal grid line unit through the transparent conductive film 2.

[0027] The transparent substrate 1 includes rigid or flexible light-transmitting base materials such as glass, plastic, and mica flakes.

[0028] The light absorption layer 4 is an MQZ3 type perovskite material, where M is at least one of Na + , Rb + , Cs + , Cu + , CH3NH3 + , CH(NH2)2 + , CH3(CH2)3NH3 + , Q is at least one of Pb 2+ , Sn 2+ , and Z is at least one of Br - , I - , Cl - .

[0029] The relationship between the charge contact layer 1 3 and the charge contact layer 2 5 is that if one is an n-type semiconductor material such as TiO2, C60, ZnO, etc., the other will automatically be a p-type semiconductor material such as NiOx, CuGaO2, PTAA, P3HT, etc.

[0030] The metal electrode 6 and the metal gate line 6' are one or more metal alloys of gold, silver, copper, aluminum, nickel, molybdenum, antimony, chromium, bismuth, palladium, and titanium.

[0031] The transparent conductive thin film 2 is FTO, ITO, IGZO, IWO, IZO, or AZO.

[0032] The present invention also provides a method for preparing a parallel-connected perovskite solar module, which is characterized by including the following steps: a) Etching the transparent substrate 1 with the transparent conductive thin film 2 by P1, and then cleaning it and setting it aside for later use; b) Sequentially depositing the charge contact layer 1 3, the light-absorbing layer (4), and the charge contact layer 2 5 on the etched clean substrate; c) Etching the substrate with the active layer (the charge contact layer 1 3, the light-absorbing layer 4, and the charge contact layer 2 5) by P2 to form a plurality of gate line filling areas; d) Simultaneously depositing the metal electrode 6 and the metal gate line 6' on the etched substrate, and depositing the metal gate line 6' in the gate line filling areas; e) Etching the substrate covered with metal by P3 to separate the battery unit and the gate line unit to form a double-wing structure metal gate line, and then connecting the wires to obtain a parallel-connected perovskite solar module.

[0033] The P1, P2, and P3 etching methods are laser etching or mechanical etching. Among them, the width of the P1 etching is 0.03 μm to 1 cm, the width of the P2 etching is 0.03 μm to 10 cm, the width of the P3 etching is 0.03 μm to 1 cm, and the dead zone width is 0.01 μm to 100 μm.

[0034] Example

[0035] According to Figure 2 Make a parallel-connected perovskite solar module according to the schematic diagram, and the preparation steps are as follows:

[0036] Step 1) Substrate preparation: Etch the FTO glass by P1 with an etching width of 1 mm, and then ultrasonically clean it with solvents such as deionized water, ethanol, and acetone for 10 min and set it aside for later use;

[0037] Step 2) Preparation of the active layer: Sequentially deposit a PTAA layer with a thickness of 20 nm, a CH(NH2)2PbI3 perovskite layer with a thickness of 700 nm, and a TiO2-Cl layer with a thickness of 15 nm on the surface of the clean FTO glass, and set it aside for later use.

[0038] Step 3) P2 etching: Perform multiple P2 etchings on the FTO glass covering the active layer with an etching width of 0.1 mm, clean the debris, and set it aside for later use;

[0039] Step 4) Preparation of metal electrodes and metal grid lines: depositing metal conductors on the surface of the FTO glass etched by P2, with a deposition thickness of 0.1 mm, for later use;

[0040] Step 5) P3 etching: Perform multiple P3 etching on the FTO glass covering the metal conductor, the etching width is 0.03mm, the width of the double wings remaining on both sides of the metal grid line is 0.01mm, and the debris is cleaned and set aside;

[0041] Step 6) Wire welding: Use wires to lead the current on both sides of the module electrodes to the external circuit.

[0042] The parallel perovskite solar module using a double-wing structure metal grid line of the present invention has the following advantages:

[0043] 1. The double-wing structure metal grid wire and each sub-battery unit are perfectly cut, avoiding the risk of leakage and significantly improving processing repeatability;

[0044] 2. The improved three-step etching process can maximize the processing and cost advantages of parallel perovskite solar modules;

[0045] 3. The dead zone area is further reduced, greatly improving the GFF (geometric fill factor);

[0046] 4. The long-term stability of the module is significantly increased, minimizing the adverse interference between sub-batteries.

[0047] It should be noted that the above is only a specific embodiment of the present invention. Obviously, the present invention is not limited to the above embodiment, and there are many variations. In short, all variations that can be directly derived or associated with the content disclosed by ordinary technicians in this field should be considered as the protection scope of the present invention.

Claims

1. A parallel-connected perovskite solar module, characterized in that, It includes a number of active battery units and a number of double-wing structure metal grid line units, which successively include a transparent substrate (1), a transparent conductive thin film (2), a first charge contact layer (3), a light absorption layer (4), a second charge contact layer (5), and a metal electrode (6) from bottom to top. It also includes seven components: a metal grid line (6’). Among them, the battery unit includes five parts: a transparent conductive thin film (2), a first charge contact layer (3), a light absorption layer (4), a second charge contact layer (5), and a metal electrode (6), which are responsible for converting solar energy into electrical energy. The grid line unit includes a metal grid line (6’) connected to the battery unit and dead zones etched and remaining on both sides of the grid line. The metal grid line (6’) is located between the battery units and is responsible for extracting the electrical energy generated by the battery units to the external circuit. The active battery units and the double-wing structure metal grid line units are connected through the transparent conductive thin film (2).

2. The perovskite solar module of the parallel connection type according to claim 1, wherein The transparent substrate (1) is a rigid or flexible light-transmitting base material.

3. The perovskite solar module of the parallel connection type according to claim 1, wherein, The light-absorbing layer (4) is a perovskite material of the MQZ3 type, where M is Na + , Rb + , Cs + , Cu + , CH3NH3 + , CH(NH2)2 + , CH3(CH2)3NH3 + , at least one of which, Q is Pb 2+ , Sn 2+ , at least one of which, Z is Br - , I - , Cl - , at least one of which.

4. The perovskite solar module of the parallel connection type according to claim 1, wherein The relationship between the first charge contact layer (3) and the second charge contact layer (5) is that if one is an n-type semiconductor material, the other is automatically a p-type semiconductor material.

5. The perovskite solar module of the parallel connection type according to claim 1, wherein The metal electrode (6) and the metal grid line (6’) are one or more metal alloys of gold, silver, copper, aluminum, nickel, molybdenum, antimony, chromium, bismuth, palladium, and titanium.

6. The perovskite solar module of the parallel connection type according to claim 1, wherein The transparent conductive thin film (2) is FTO, ITO, IGZO, IWO, IZO, or AZO.

7. A method for preparing the parallel-connected perovskite solar module according to any one of claims 1 to 6, characterized in that, It includes the following steps: a) Etch the transparent substrate (1) with the transparent conductive thin film (2), and then clean it and set it aside for use; b) Deposit the first charge contact layer (3), the light absorption layer (4), and the second charge contact layer (5) on the etched clean substrate in sequence; c) Etch the substrate with the first charge contact layer (3), the light absorption layer (4), and the second charge contact layer (5) by P2 to form a number of grid line landfill areas; d) Deposit the metal electrode (6) and the metal grid line (6’) on the etched substrate at the same time, and the metal grid line (6’) is deposited in the grid line landfill areas; e) Etch the substrate covered with metal by P3 to separate the battery units and the grid line units to form a double-wing structure metal grid line, and then connect the wires to obtain a parallel-connected type perovskite solar module.

8. The preparation method of a parallel-connected perovskite solar module according to claim 7, characterized in that, The P1, P2, and P3 etching methods are laser etching or mechanical etching.

9. The preparation method of a parallel-connected perovskite solar module according to claim 7, characterized in that, The width of the P1 etching is 0.03 μm to 1 cm, the width of the P2 etching is 0.03 μm to 10 cm, the width of the P3 etching is 0.03 μm to 1 cm, and the width of the dead zone is 0.01 μm to 100 μm.

10. The preparation method of a parallel-connected perovskite solar module according to claim 7, characterized in that The thickness of the metal grid line (6’) is 0.03 μm to 500 μm.

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