Foldable integrated perovskite solar cell and manufacturing method thereof

Abstract

The invention discloses a foldable integrated perovskite solar cell and a manufacturing method thereof, the foldable integrated perovskite solar cell is innovatively realized, specifically, a laser segmentation process is used to replace a hinge structure with a large physical size and a complex installation process, and the manufacturing cost is reduced. The light and thin perovskite cell is endowed with foldable performance while segmentation and packaging of the perovskite cell unit are realized, the production process is simplified, the manufacturing cost is reduced, the perovskite cell unit is kept flat in the folding process, the problem that the performance of the cell is reduced due to the fact that a functional layer is damaged when the perovskite cell unit is directly bent is avoided, and the performance of the cell is improved. According to the perovskite solar cell, the excellent photoelectric characteristic of the perovskite material is fully exerted, the efficiency loss caused by the failure of the perovskite cell unit is effectively reduced, the overall efficiency of the perovskite solar cell is improved, and the service life of the cell is prolonged. The bending characteristic is provided by the crease structure, so that the perovskite solar cell has great space utilization efficiency.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of photovoltaic power generation, and particularly relates to a foldable integrated perovskite solar cell and a manufacturing method thereof. BACKGROUND

[0002] In the field of photovoltaic power generation, organic-inorganic hybrid perovskite materials have attracted extensive attention and rapid development and application due to their excellent photoelectric properties and low-cost preparation methods. Among them, the efficiency of organic-inorganic hybrid perovskite single-junction solar cells has reached 27%, close to the highest efficiency of the current mainstream silicon-based solar cells.

[0003] For foldable solar cells: I. It can be a crystalline silicon solar cell, such as a foldable solar cell using a Miura fold design. Based on an encapsulated special-shaped thick plate cell panel, hinges are used to connect each cell panel according to the thick plate Miura fold structure design to realize overall mechanical deployment and storage. Although this type of foldable cell can achieve folding, it has the following problems: the cost of processing special-shaped silicon cell panels is high; the thick plate fold structure design is complex; the hinge installation process is complex and increases the cost; the minimum folding area is limited by the available silicon cell area, and the self-weight is large, which is contrary to portability and storage.

[0004] II. It can be a thin-film solar cell, which specifically structures the available thin-film cell into a sub-cell, attaches it to a frame (which can be a thin film or a movable rod frame), and constructs an electrical connection. In this way, the movable assembly has poor reliability, the assembly manufacturing process is complex, the electrical connection has poor reliability, the material cost is ultimately increased, and the assembly reliability is also reduced, which is not conducive to the realization of the portable field of solar cells.

[0005] In addition, compared with the folding of the flexible cell reel relying on the fold, the folding cell does not need to consider the folding resistance of the thin film, the cell design is simple, high-efficiency can be directly achieved by using high-performance cell technology, and performance degradation caused by deformation can be well avoided. However, the flexible reel winding has a minimum curvature radius limit, and the overall space expansion efficiency is not necessarily higher than that of the folding cell.

[0006] The light and thin characteristics of perovskite materials provide a physical basis for folding from a square meter to a handheld size, filling the gap in the small and portable application field of existing folding solar cells. However, for perovskite solar cells, when the device is directly bent, the functional layer is subjected to stress, which easily causes the performance of fragile materials such as TCO (Transparent Conductive Oxide) electrodes and perovskite photoactive layers in the cell to deteriorate, leading to a decrease in cell performance or even failure, which brings challenges to the realization of foldable perovskite solar cells. SUMMARY

[0007] To address the aforementioned problems in the prior art, this invention provides a foldable, integrated perovskite solar cell and its fabrication method. The technical problem to be solved by this invention is achieved through the following technical solution: In a first aspect, embodiments of the present invention provide a foldable integrated perovskite solar cell, the fabrication method comprising: Fabricating and encapsulating perovskite solar cell units; the process of fabricating and encapsulating perovskite solar cell units includes: selecting a polymer substrate and preparing a transparent conductive layer on the polymer substrate; selectively etching the transparent conductive layer using a laser until several first segmented grooves are formed on the surface of the polymer substrate; sequentially preparing a hole transport layer, a perovskite light absorption layer, and an electron transport layer on the transparent conductive layer and within the first segmented grooves; selectively etching the electron transport layer using a laser until several second segmented grooves are formed on the surface of the transparent conductive layer, thereby etching to form several perovskite sub-cells; and selectively etching the electron transport layer using a laser until the transparent conductive layer is clear. A plurality of third dividing grooves are formed on the surface of the conductive layer to etch a plurality of perovskite solar cell units, each perovskite solar cell unit comprising a plurality of perovskite sub-cells; the transparent conductive layer at each third dividing groove is selectively etched using a laser until the surface of the polymer substrate is formed, forming a cathode and an anode on both sides of each perovskite solar cell unit; a top electrode is fabricated on each perovskite sub-cell within the third dividing groove; the top electrode is selectively etched using a laser until a plurality of fourth dividing grooves are formed on the surface of the transparent conductive layer to divide the continuous top electrode, thereby connecting the perovskite sub-cells in series within the perovskite solar cell unit; each perovskite solar cell unit is then encapsulated. A laser is used to create grooves on both sides of a polymer substrate between adjacent perovskite solar cell units to form a foldable structure. The inter-cell electrical interconnection structure is fabricated and encapsulated to achieve electrical connection between the perovskite solar cell units.

[0008] In one embodiment of the present invention, a laser is used to selectively etch a transparent conductive layer until a plurality of first segmented grooves are formed on the surface of a polymer substrate, including: A green laser is used to selectively etch the transparent conductive layer until several first segmentation grooves are formed on the surface of the polymer substrate. The specific process parameters are as follows: under a nitrogen atmosphere, the laser power is 12.5% ​​of the total energy density of the green laser, the scanning speed is 100mm / s~500mm / s, and the laser pulse frequency is 200KHz.

[0009] In one embodiment of the present invention, a laser is used to selectively etch the electron transport layer until a plurality of second segmented grooves are formed on the surface of the transparent conductive layer, including: A green laser is used to selectively etch the electron transport layer until several second segmented grooves are formed on the surface of the transparent conductive layer. The specific process parameters are as follows: under a nitrogen atmosphere, the laser power is 4% of the total energy density of the green laser, the scanning speed is 200mm / s~800mm / s, the scanning spacing is 20μm, and the laser pulse frequency is 220kHz.

[0010] In one embodiment of the present invention, a laser is used to selectively etch the electron transport layer until a plurality of third dividing grooves are formed on the surface of the transparent conductive layer, including: The electron transport layer is selectively etched using an infrared laser until several third-division grooves are formed on the surface of the transparent conductive layer. The specific process parameters are as follows: under an argon atmosphere, the laser power is 2% of the total energy density of the infrared laser, the scanning speed is 2500mm / s~3000mm / s, and the laser pulse frequency is 50KHz. The width of the third-division groove is 3.5a~4a, where a is the thickness of the polymer substrate.

[0011] In one embodiment of the present invention, a laser is used to selectively etch the transparent conductive layer at each third dividing groove down to the surface of the polymer substrate, including: The transparent conductive layer at each third dividing groove is selectively etched using an infrared laser until it reaches the surface of the polymer substrate. The specific process parameters are as follows: under an argon atmosphere, the laser power is 2% of the total energy density of the infrared laser, the scanning speed is 2500mm / s~3000mm / s, and the laser pulse frequency is 50KHz.

[0012] In one embodiment of the present invention, a laser is used to selectively etch the top electrode until a plurality of fourth segmented grooves are formed on the surface of the transparent conductive layer, including: A green laser is used to selectively etch the top electrode until several fourth segmented grooves are formed on the surface of the transparent conductive layer. The specific process parameters are: under a nitrogen atmosphere, the laser power is 4% of the total energy density of the green laser, the scanning speed is 1000mm / s~1200mm / s, and the laser pulse frequency is 400kHz.

[0013] In one embodiment of the present invention, each perovskite solar cell is packaged, comprising: Laser welding encapsulation technology is used, and each perovskite cell is encapsulated using PET film; Encapsulate the electrical interconnection structure between units, including: Laser welding encapsulation technology is used, and PET film is used to encapsulate the electrical interconnection structure between each unit.

[0014] In one embodiment of the present invention, a crease structure is formed by grooving the front and back sides of a polymer substrate between adjacent perovskite solar cell cells using a laser, including: According to the folding requirements, a laser is used to rough groove the front and back sides of the polymer substrate between adjacent perovskite solar cell units to form several rough processing grooves. Each roughing groove is pre-treated using a laser; The thickness of the polymer substrate at each point in each roughing groove after pretreatment is determined using a white light interferometric thickness gauge in order to generate a fine grooving etching path. Along the fine grooving etching path, a laser is used to continue fine grooving to form a crease structure.

[0015] In one embodiment of the present invention, a plurality of roughing grooves are formed on the front and back sides of a polymer substrate between adjacent perovskite solar cell units using a laser, including: Several roughing grooves are formed on the front and back sides of a polymer substrate between adjacent perovskite solar cell units using an infrared laser. The specific process parameters are as follows: the laser power is 50% of the total energy density of the infrared laser, the laser frequency is 50 kHz, the scanning speed is 100 mm / s to 200 mm / s, and the scanning spacing is 100 μm to 150 μm. Several roughing grooves with a groove depth of 75%a to 85%a and a groove width of 3a to 3.5a are formed on the front and back sides of the polymer substrate between adjacent perovskite solar cell units, where a is the thickness of the polymer substrate. Each roughing groove is pre-treated using a laser, including: Each roughing groove was pretreated using an ultraviolet laser; the specific process parameters were: ultraviolet laser pulse energy density of 5.22 J / cm². 2 The laser frequency is 500KHz, the scanning speed is 200mm / s~300mm / s, and the scanning distance is 20μm; Along the fine grooving etching path, a laser is used to continue fine grooving to form a crease structure, including: Along the fine grooving etching path, a UV laser is used to continue fine grooving to form a crease structure; the specific process parameters are: UV laser pulse energy density of 5.22 J / cm². 2 The laser frequency is 500KHz, and the scanning speed is 200mm / s~300mm / s. Finally, grooves with a depth of 89%a~91%a and a width of 3a~4a are formed on the front and back sides of the polymer substrate between adjacent perovskite solar cell units as crease structures.

[0016] Secondly, embodiments of the present invention provide a foldable integrated perovskite solar cell, which is manufactured according to any of the manufacturing methods of the foldable integrated perovskite solar cell described in the first aspect.

[0017] The beneficial effects of this invention are: This invention proposes a method for fabricating a foldable integrated perovskite solar cell, innovatively achieving a foldable integrated perovskite solar cell. Specifically, it uses a laser segmentation process to replace the large physical size and complex installation process of the hinge structure. This method achieves the segmentation and encapsulation of perovskite cell units while simultaneously endowing the thin and lightweight perovskite cell with foldable properties, simplifying the production process and reducing manufacturing costs. During the folding process, the perovskite cell units remain flat, avoiding the problem of functional layer damage and performance degradation caused by direct bending of the perovskite cell units. This fully utilizes the excellent photoelectric properties of perovskite material, effectively reducing efficiency loss caused by perovskite cell unit failure, improving the overall efficiency of the foldable perovskite solar cell module, and extending the battery's lifespan. The crease structure provides bendability, giving the perovskite solar cell extremely high space utilization efficiency. In summary, the preparation method provided by this invention takes into account both the requirements of preparation process and cost, and has the advantages of low cost, easy implementation and easy reproducibility. It also shows strong application potential, effectively improving the application adaptability of perovskite solar cells in flexible electronic devices, wearable products, curved building integration and other fields, and providing an ideal way to expand the application scenarios of perovskite solar cells.

[0018] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0019] Figure 1 This is a schematic flowchart illustrating a method for fabricating a foldable integrated perovskite solar cell according to an embodiment of the present invention. Figures 2(a) to 2(n) This is a schematic diagram of the fabrication process of the foldable integrated perovskite solar cell provided in the embodiment of the present invention. Figure 3 A schematic diagram of a foldable integrated perovskite solar cell provided in an embodiment of the present invention after folding; Figure 4 This is a schematic diagram of the structure of a foldable integrated perovskite solar cell provided in an embodiment of the present invention; Figure 5 This is a schematic diagram of the foldable integrated perovskite solar cell provided in an embodiment of the present invention.

[0020] Explanation of reference numerals in the attached figures: 1-Perovskite solar cell; 2-Fold structure; 3-Inter-cell electrical interconnection structure; Detailed Implementation The present invention will be further described in detail below with reference to specific embodiments, but the implementation of the present invention is not limited thereto.

[0021] Firstly, please see Figure 1 This invention provides a foldable integrated perovskite solar cell, the fabrication method of which includes: S10. Fabricating and encapsulating perovskite solar cell units; wherein, the process of fabricating and encapsulating perovskite solar cell units includes: selecting a polymer substrate and preparing a transparent conductive layer on the polymer substrate; selectively etching the transparent conductive layer using a laser until several first segmented grooves are formed on the surface of the polymer substrate; sequentially preparing a hole transport layer, a perovskite light absorption layer, and an electron transport layer on the transparent conductive layer and within the first segmented grooves; selectively etching the electron transport layer using a laser until several second segmented grooves are formed on the surface of the transparent conductive layer, thereby etching to form several perovskite sub-cells; selectively etching the electron transport layer using a laser until... A number of third dividing grooves are formed on the surface of the transparent conductive layer to etch a number of perovskite solar cell units, each of which includes a number of perovskite sub-cells. A laser is then used to selectively etch the transparent conductive layer at each third dividing groove down to the surface of the polymer substrate, forming a cathode and an anode on both sides of each perovskite solar cell unit. A top electrode is fabricated on each perovskite sub-cell within the third dividing groove. A laser is then used to selectively etch the top electrode until a number of fourth dividing grooves are formed on the surface of the transparent conductive layer, thus dividing the continuous top electrode and connecting the perovskite sub-cells within the perovskite solar cell unit in series. Each perovskite solar cell unit is then encapsulated.

[0022] In this embodiment of the invention, a polymer substrate is selected as shown in Figure 2(a), and a transparent conductive layer is prepared on the polymer substrate as shown in Figure 2(b). The process includes: selecting and cleaning the polymer substrate; specifically, ultrasonically cleaning a polymer (polycarbonate PC) substrate with a thickness of 0.4 mm to 1.2 mm in Decon-90 aqueous solution, deionized water, and anhydrous ethanol for 10 min to 20 min respectively. Next, a transparent conductive layer is prepared on the cleaned polymer substrate using magnetron sputtering; specifically, the process is carried out under argon atmosphere at room temperature with a pressure of 2 × 10⁻⁶. -4 At a sputtering power of 100W, IZO (indium zinc oxide) was radio frequency sputtered onto a polymer substrate to prepare a transparent conductive layer with a thickness of 50nm~400nm. The material of the transparent conductive layer is not limited to IZO, but can also be ITO (indium tin oxide), FTO (fluorine-doped tin oxide), or other materials that can be used as transparent electrodes.

[0023] In this embodiment of the invention, a laser is used to selectively etch a transparent conductive layer until a plurality of first segmented grooves are formed on the surface of a polymer substrate, as shown in Figure 2(c). This includes: using a green laser to selectively etch the transparent conductive layer until a plurality of first segmented grooves are formed on the surface of the polymer substrate; the specific process parameters are: under a nitrogen atmosphere, the laser power is 12.5% ​​of the total energy density of the green laser, the scanning speed is 100 mm / s to 500 mm / s, and the laser pulse frequency is 200 kHz. Each first segmented groove is etched in one pass, all first segmented grooves are arranged in parallel, and the width of each first segmented groove is unlimited and can be designed according to actual needs, for example, it can be 10 μm.

[0024] In this embodiment of the invention, a hole transport layer, a perovskite light absorption layer, and an electron transport layer are sequentially fabricated on a transparent conductive layer and within a first segmented groove, including: The preparation of the hole transport layer is shown in Figure 2(d). The specific process is as follows: the etched sample is ultrasonically cleaned with anhydrous ethanol for 20 min, then subjected to ultraviolet ozone irradiation for 10 min, and dried at 120℃ for 15 min. A 1 nm~2 nm Al2O3 (aluminum oxide) transition layer is grown using ALD (Atomic Layer Deposition) technology, and then a 30 nm~50 nm NiO layer is grown using ALD technology. x (Nickel oxide), all grown at 180℃; after 10 min of UV ozone irradiation, 0.33 mg / mL Me-4Pacz SAMs were coated onto the sample surface at a speed of 20 mm / s using a slit coating device, and then annealed at 100℃ for 10 min on a hot plate to form composite NiO. x / SAMs Hole Transport Layer.

[0025] As shown in Figure 2(e), the perovskite light-absorbing layer was prepared using a mature perovskite thin film preparation process, including but not limited to solution methods. Furthermore, the composition of the perovskite absorber layer is not limited to organic, hybrid, or all-inorganic perovskites. For example, when the material of the perovskite light-absorbing layer is Cs... 0.05 (MA 0.2 FA 0.8 ) 0.95 Pb(I 0.80 Br 0.2 )3. When preparing the thin film, the slit coating flash evaporation method is used. The specific process is as follows: First, prepare Cs 0.05 (MA 0.2 FA 0.8 ) 0.95 Pb(I 0.80 Br 0.2)3 Mixed solution, with 1.3 mmol / mL Cs 0.05 (MA 0.2 FA 0.8 ) 0.95 Pb(I 0.80 Br 0.2 3. Dissolve the mixed solution in DMF (N,N-dimethylformamide):NMP (N-methylpyrrolidone):DMOS (dimethyl sulfoxide) = 8:2:0.2, and stir thoroughly until dissolved. Before use, filter the solution through a 0.6 μm PTFE (polytetrafluoroethylene) membrane to form the perovskite precursor solution. Then, use a slit coating device to uniformly coat the perovskite precursor solution onto the sample surface, with a coating gap of 60 μm to 120 μm, a coating speed of 30 mm / s to 60 mm / s, and a solution supply rate of 3 μL / cm³. 2 ~8μL / cm 2 The ambient temperature was controlled at 22℃ and the humidity at 30%. After flash evaporation at 5 Pa for 30 seconds, the material was annealed at 100℃ for 10 minutes to form a perovskite light-absorbing layer with a thickness of 100nm~800nm, yielding IZO-NiO. x / SAMs-Cs 0.05 (MA 0.2 FA 0.8 ) 0.95 Pb(I 0.80 Br 0.2 )3 Battery film.

[0026] The fabrication of the electron transport layer is shown in Figure 2(f). The specific process is as follows: 15nm~20nm C atoms are sequentially deposited on the sample surface using a vacuum evaporation device. 60 A layer and a 5nm~10nm BCP barrier layer form C 60 / BCP electron transport layer, made of NiO x / SAMs hole transport layer, Cs 0.05 (MA 0.2 FA 0.8 ) 0.95 Pb(I 0.80 Br 0.2 3. C 60 The BCP electron transport layer constitutes the photoactive layer. During the fabrication of the electron transport layer, it is essential to maintain a vacuum level within the evaporation chamber between the two evaporation processes.

[0027] In this embodiment of the invention, a laser is used to selectively etch the electron transport layer until a plurality of second segmented grooves are formed on the surface of the transparent conductive layer, as shown in Figure 2(g). This includes: using a green laser to selectively etch the electron transport layer until a plurality of second segmented grooves are formed on the surface of the transparent conductive layer; the specific process parameters are: under a nitrogen atmosphere, the laser power is 4% of the total energy density of the green laser, the scanning speed is 200 mm / s to 800 mm / s, the scanning spacing is 20 μm, and the laser pulse frequency is 220 kHz. Each second segmented groove is etched multiple times, for example, at least four times, with each etching width being the same as the etching width of the first segmented groove, resulting in an exposed transparent conductive layer width ≥ 40 μm; each second segmented groove is parallel to the first segmented groove, and the distance between a second segmented groove and an adjacent first segmented groove is 50 μm.

[0028] After etching in the second dividing groove, several perovskite sub-cells are formed. The function of the second dividing groove includes: ensuring good contact between the subsequently grown top electrode and the transparent conductive layer, while reducing the series resistance of two adjacent perovskite sub-cells.

[0029] In this embodiment of the invention, a laser is used to selectively etch the electron transport layer until several third dividing grooves are formed on the surface of the transparent conductive layer, as shown in Figure 2(h). This includes: using an infrared laser to selectively etch the electron transport layer until several third dividing grooves are formed on the surface of the transparent conductive layer; the specific process parameters are: under an argon atmosphere, the laser power is 2% of the total energy density of the infrared laser, the scanning speed is 2500mm / s~3000mm / s, and the laser pulse frequency is 50KHz; wherein, the width of the third dividing groove is 3.5a~4a, where a is the thickness of the polymer substrate. It can be seen that after etching with the second dividing groove, the distance between the perovskite solar cell units formed by the etching is determined by the polymer substrate. For example, when the thickness of the polymer substrate is 0.5mm, the distance between the perovskite solar cell units is 1.75mm~2mm.

[0030] It should be noted that the number of perovskite sub-cells in a perovskite solar cell unit depends on the requirements of the folding structure. For example, to achieve a folding structure similar to the traditional Miura structure, the perovskite sub-cells in the perovskite solar cell unit have equal areas and meet the parallelogram requirements of the Miura folding structure.

[0031] In this embodiment of the invention, a laser is used to selectively etch the transparent conductive layer at each third segmentation groove until it reaches the surface of the polymer substrate, as shown in Figure 2(i). This includes: using an infrared laser to selectively etch the transparent conductive layer at each third segmentation groove until it reaches the surface of the polymer substrate; the specific process parameters are: under an argon atmosphere, the laser power is 2% of the total energy density of the infrared laser, the scanning speed is 2500 mm / s to 3000 mm / s, and the laser pulse frequency is 50 kHz. Here, to achieve electrode patterning, the exposed cathode and anode on both sides of each perovskite solar cell unit are formed. It can be seen that the exposed cathode and anode are transparent conductive layers, i.e., transparent electrodes. To achieve better conductivity, an Ag layer can be deposited on these exposed transparent electrodes, specifically formed simultaneously with the top electrode using a mask.

[0032] As shown in Figure 2(j), the top electrode of this invention is fabricated on each perovskite sub-cell within the third segmentation groove, including: using a vapor deposition process to deposit the top electrode on IZO-NiO. x / SAMs-Cs 0.05 (MA 0.2 FA 0.8 ) 0.95 Pb(I 0.80 Br 0.2 )3-C 60 / Ag (silver) with a thickness of 30nm~150nm is deposited on the BCP battery thin film to form the top electrode.

[0033] In this embodiment of the invention, a laser is used to selectively etch the top electrode until a plurality of fourth segmented grooves are formed on the surface of the transparent conductive layer, as shown in Figure 2(k). This includes: using a green laser to selectively etch the top electrode until a plurality of fourth segmented grooves are formed on the surface of the transparent conductive layer; the specific process parameters are: under a nitrogen atmosphere, the laser power is 4% of the total energy density of the green laser, the scanning speed is 1000 mm / s to 1200 mm / s, and the laser pulse frequency is 400 kHz. Each fourth segmented groove is etched multiple times, for example, at least twice, with each etching width being the same as the etching width of the first segmented groove, to cut off the continuous top electrode and form a series electrical connection between the perovskite sub-cells; each fourth segmented groove is parallel to the first segmented groove, the distance between the fourth segmented groove and the adjacent second segmented groove is 50 μm, and they are staggered from the first segmented groove.

[0034] In this embodiment of the invention, each perovskite solar cell is encapsulated as shown in Figure 2(l), including: using laser welding technology and encapsulating each perovskite solar cell with a PET film; specifically, a 50μm PET film is flatly and void-freely covered on IZO-NiO. x / SAMs-Cs 0.05 (MA0.2 FA 0.8 ) 0.95 Pb(I 0.80 Br 0.2 )3-C 60 On the surface of the BCP-Ag battery film, the battery film and polymer substrate are pressed together, and an infrared laser is used to heat along the edge of the battery film, welding the PET (polyethylene terephthalate) film to the polymer substrate to form a weld seam of 200μm~300μm. The excess covering is then cut off and peeled off. The cathode and anode on both sides of each perovskite battery cell are not within the encapsulation area. This invention uses laser welding encapsulation technology to improve component stability and meet the application requirements of foldable devices in portable energy scenarios.

[0035] S20. A laser is used to create grooves on both sides of the polymer substrate between adjacent perovskite solar cell units to form a folded structure, which makes the polymer substrate foldable.

[0036] In this embodiment of the invention, a laser is used to create grooves on both sides of a polymer substrate between adjacent perovskite solar cell units to form a crease structure. This includes: using a laser to create rough grooves on both sides of the polymer substrate between adjacent perovskite solar cell units to form several rough machining grooves; using a laser to pre-process each rough machining groove; using a white light interferometric thickness gauge to determine the thickness of the polymer substrate at various points within each pre-processed rough machining groove to generate a fine grooving etching path; and continuing to use a laser to perform fine grooving along the fine grooving etching path to form the crease structure. More specifically: In this embodiment of the invention, a laser is used to rough groove the front and back sides of a polymer substrate between adjacent perovskite solar cell units to form several rough machining grooves, including: According to the folding requirements, an infrared laser is used to rough groove the front and back sides of the polymer substrate between adjacent perovskite solar cell units to form several rough processing grooves. The specific process parameters are: the laser power is 50% of the total energy density of the infrared laser, the laser frequency is 50 kHz, the scanning speed is 100 mm / s to 200 mm / s, and the scanning spacing is 100 μm to 150 μm. Several rough processing grooves with a groove depth of 75%a to 85%a and a groove width of 3a to 3.5a are formed on the front and back sides of the polymer substrate between adjacent perovskite solar cell units, where a is the thickness of the polymer substrate.

[0037] Each roughing groove is pre-treated using a laser, including: pre-treatment of each roughing groove using an ultraviolet laser; specific process parameters are: ultraviolet laser pulse energy density of 5.22 J / cm². 2The laser frequency is 500KHz, the scanning speed is 200mm / s~300mm / s, and the scanning spacing is 20μm, in order to trim the roughing groove after infrared laser etching and remove the yellowed and carbonized surface.

[0038] Along the fine grooving etching path, a laser is used to continue fine grooving to form a crease structure, including: along the fine grooving etching path, a UV laser is used to continue fine grooving to form a crease structure; the specific process parameters are: UV laser pulse energy density of 5.22 J / cm². 2 The laser frequency is 500 kHz, and the scanning speed is 200 mm / s to 300 mm / s. This results in grooves with a depth of 89%a to 91%a and a width of 3a to 4a forming a crease structure on both sides of the polymer substrate between adjacent perovskite solar cell units. For example, when the polymer substrate thickness is 0.5 mm, the groove depth is 445 μm to 455 μm and the groove width is 1.5 mm to 2 mm. Figure 2(m) illustrates the structure after grooving on the reverse side of the polymer substrate.

[0039] According to the requirements of folding structures, such as the simple structure and equal unit area of ​​the Miura folding structure, fold structures are etched on the front and back sides of the polymer substrate. Taking the sunlight incident surface of the polymer substrate as the front side, the folds on the front side are called valley folds, and the folds on the back side are called mountain folds. The fold structures are fabricated on polymer substrates of different thicknesses, and the folding method can be adjusted according to the design of the spatial folding structure and the required folding-to-unfold ratio.

[0040] S30. Fabricate and encapsulate the inter-cell electrical interconnection structure to achieve electrical connection between the perovskite cell units.

[0041] As shown in Figure 2(n), the inter-cell electrical interconnection structure in this embodiment of the invention is used to realize the electrical connection between the perovskite battery cells. This includes: according to the designed electrical connection relationship, such as series connection, using a metal vapor deposition process or a conductive silver paste coating process to create the inter-cell electrical interconnection structure between the perovskite battery cells. For example, using a vapor deposition process to deposit a 100nm thin Ag layer between the perovskite battery cells, the electrical connection between the perovskite battery cells is realized through the inter-cell electrical interconnection structure.

[0042] In this embodiment of the invention, the encapsulation of the inter-unit electrical interconnection structure includes: using a laser welding encapsulation process and encapsulating each inter-unit electrical interconnection structure with a PET film. Specifically, for example, the PET film is welded onto the inter-unit electrical interconnection structure using a laser welding process to complete the encapsulation of the inter-unit electrical interconnection structure.

[0043] As shown in Figure 2(n), Figure 2(n) is a schematic diagram of the foldable perovskite solar cell provided in an embodiment of the present invention. The perovskite solar cell unit, from bottom to top, includes: a polymer substrate, a hole transport layer, a perovskite light-absorbing layer, an electron transport layer, a top electrode, and a PET film. Each perovskite solar cell unit consists of three perovskite sub-cells connected in series from left to right. The left side has a pre-placed anode, and the right side has a cathode, but this is not limited to this; depending on electrical connection requirements, the cathode and anode can be arbitrarily arranged on the four sides of the perovskite solar cell unit. Taking two perovskite solar cell units as an example... Figure 3 This illustrates that the two perovskite solar cell units are folded along the folding structure.

[0044] It should be noted that acceptable etching errors are allowed throughout the etching process of perovskite solar cells. For example, an etching error of ±0.05a is allowed in the rough grooving etching process, and an etching error of ±0.01a is allowed in the fine grooving etching process.

[0045] In summary, the fabrication method for foldable integrated perovskite solar cells proposed in this invention innovatively achieves foldable integrated perovskite solar cells. Specifically, it uses laser segmentation technology to replace the hinge structure, which is physically large and has a complex installation process. This method achieves both segmentation and encapsulation of perovskite cell units while simultaneously imparting foldable properties to the thin and lightweight perovskite cells, simplifying the production process and reducing manufacturing costs. During the folding process, the perovskite cell units remain flat, avoiding the problem of functional layer damage and performance degradation caused by direct bending of the perovskite cell units. This fully utilizes the excellent photoelectric properties of perovskite material, effectively reduces efficiency loss caused by perovskite cell unit failure, improves the overall efficiency of the foldable perovskite solar cell module, and extends the battery's lifespan. The crease structure provides bendability, giving the perovskite solar cells extremely high space utilization efficiency. In summary, the preparation method provided by this invention takes into account both the requirements of preparation process and cost, and has the advantages of low cost, easy implementation and easy reproducibility. It also shows strong application potential, effectively improving the application adaptability of perovskite solar cells in flexible electronic devices, wearable products, curved building integration and other fields, and providing an ideal way to expand the application scenarios of perovskite solar cells.

[0046] Secondly, please see Figure 4 This invention provides a foldable integrated perovskite solar cell, which is fabricated according to any of the methods described in the first aspect of the invention. Figure 4As shown, all perovskite solar cell units 1 form a basic 5×8 array, where each perovskite solar cell unit is 2.1cm×2cm in size, a parallelogram with an acute angle of 90°-α, for example, α=10°. Each perovskite solar cell unit consists of multiple perovskite sub-cells connected in series. Adjacent perovskite solar cell units are connected by a crease structure 2 and an inter-unit electrical interconnection structure 3. Figure 5 The illustration shows a folding configuration of a 5×8 perovskite solar cell designed according to folding requirements. A laser is used to create grooves in the polymer substrate between the perovskite cell units, forming bendable crease structures on both the front and back sides. Orange dashed lines represent valley creases etched on the front side, and blue dashed lines represent mountain creases etched on the back side. Folding all the perovskite cell units according to the crease structure forms the structure on the right. This folded structure is more suitable for small, portable applications. The positions of the valley and mountain creases differ depending on the folding requirements, but the process used to form these crease structures is the same as in S20.

[0047] As for the structural embodiment of the second aspect, since it is basically similar to the manufacturing method embodiment of the first aspect, the description is relatively simple. For relevant details, please refer to the description of the manufacturing method embodiment of the first aspect.

[0048] In the description of this invention, it should be understood that the terms "first" and "second" 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. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0049] Although the invention has been described herein in conjunction with various embodiments, those skilled in the art, by reviewing the specification and accompanying drawings, will understand and implement other variations of the disclosed embodiments in carrying out the claimed invention. In the specification, the word "comprising" does not exclude other components or steps, and "a" or "an" does not exclude a plurality. While certain measures are described in different embodiments, this does not mean that these measures cannot be combined to produce good results.

[0050] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such modifications and substitutions should be considered within the scope of protection of the present invention.

Claims

1. A method for fabricating a foldable, integrated perovskite solar cell, characterized in that, The manufacturing method includes: Fabricating and encapsulating perovskite solar cell units; the process of fabricating and encapsulating perovskite solar cell units includes: selecting a polymer substrate and preparing a transparent conductive layer on the polymer substrate; selectively etching the transparent conductive layer using a laser until several first segmented grooves are formed on the surface of the polymer substrate; sequentially preparing a hole transport layer, a perovskite light absorption layer, and an electron transport layer on the transparent conductive layer and within the first segmented grooves; selectively etching the electron transport layer using a laser until several second segmented grooves are formed on the surface of the transparent conductive layer, thereby etching to form several perovskite sub-cells; and selectively etching the electron transport layer using a laser until the transparent conductive layer is clear. A plurality of third dividing grooves are formed on the surface of the conductive layer to etch a plurality of perovskite solar cell units, each perovskite solar cell unit comprising a plurality of perovskite sub-cells; the transparent conductive layer at each third dividing groove is selectively etched using a laser until the surface of the polymer substrate is formed, forming a cathode and an anode on both sides of each perovskite solar cell unit; a top electrode is fabricated on each perovskite sub-cell within the third dividing groove; the top electrode is selectively etched using a laser until a plurality of fourth dividing grooves are formed on the surface of the transparent conductive layer to divide the continuous top electrode, thereby connecting the perovskite sub-cells in series within the perovskite solar cell unit; each perovskite solar cell unit is then encapsulated. A laser is used to create grooves on both sides of a polymer substrate between adjacent perovskite solar cell units to form a foldable structure. The inter-cell electrical interconnection structure is fabricated and encapsulated to achieve electrical connection between the perovskite solar cell units.

2. The method for fabricating the foldable integrated perovskite solar cell according to claim 1, characterized in that, A laser is used to selectively etch the transparent conductive layer until several first segmented grooves are formed on the surface of the polymer substrate, including: A green laser is used to selectively etch the transparent conductive layer until several first segmentation grooves are formed on the surface of the polymer substrate. The specific process parameters are as follows: under a nitrogen atmosphere, the laser power is 12.5% ​​of the total energy density of the green laser, the scanning speed is 100mm / s~500mm / s, and the laser pulse frequency is 200KHz.

3. The method for fabricating the foldable integrated perovskite solar cell according to claim 1, characterized in that, A laser is used to selectively etch the electron transport layer until several second-divided grooves are formed on the surface of the transparent conductive layer, including: A green laser is used to selectively etch the electron transport layer until several second segmented grooves are formed on the surface of the transparent conductive layer. The specific process parameters are as follows: under a nitrogen atmosphere, the laser power is 4% of the total energy density of the green laser, the scanning speed is 200mm / s~800mm / s, the scanning spacing is 20μm, and the laser pulse frequency is 220kHz.

4. The method for fabricating the foldable integrated perovskite solar cell according to claim 1, characterized in that, A laser is used to selectively etch the electron transport layer until several third-order grooves are formed on the surface of the transparent conductive layer, including: The electron transport layer is selectively etched using an infrared laser until several third-division grooves are formed on the surface of the transparent conductive layer. The specific process parameters are as follows: under an argon atmosphere, the laser power is 2% of the total energy density of the infrared laser, the scanning speed is 2500mm / s~3000mm / s, and the laser pulse frequency is 50KHz. The width of the third-division groove is 3.5a~4a, where a is the thickness of the polymer substrate.

5. The method for fabricating the foldable integrated perovskite solar cell according to claim 1, characterized in that, The transparent conductive layer at each third dividing groove is selectively etched using a laser until it reaches the surface of the polymer substrate, including: The transparent conductive layer at each third dividing groove is selectively etched using an infrared laser until it reaches the surface of the polymer substrate. The specific process parameters are as follows: under an argon atmosphere, the laser power is 2% of the total energy density of the infrared laser, the scanning speed is 2500mm / s~3000mm / s, and the laser pulse frequency is 50KHz.

6. The method for fabricating a foldable integrated perovskite solar cell according to claim 1, characterized in that, A laser is used to selectively etch the top electrode until several fourth-divided grooves are formed on the surface of the transparent conductive layer, including: A green laser is used to selectively etch the top electrode until several fourth segmented grooves are formed on the surface of the transparent conductive layer. The specific process parameters are: under a nitrogen atmosphere, the laser power is 4% of the total energy density of the green laser, the scanning speed is 1000mm / s~1200mm / s, and the laser pulse frequency is 400kHz.

7. The method for fabricating a foldable integrated perovskite solar cell according to claim 1, characterized in that, Each perovskite solar cell is packaged, including: Laser welding encapsulation technology is used, and each perovskite cell is encapsulated using PET film; Encapsulate the electrical interconnection structure between units, including: Laser welding encapsulation technology is used, and PET film is used to encapsulate the electrical interconnection structure between each unit.

8. The method for fabricating a foldable integrated perovskite solar cell according to claim 1, characterized in that, A crease structure is formed by grooving the front and back sides of a polymer substrate between adjacent perovskite solar cell cells using a laser, including: According to the folding requirements, a laser is used to rough groove the front and back sides of the polymer substrate between adjacent perovskite solar cell units to form several rough processing grooves. Each roughing groove is pre-treated using a laser; The thickness of the polymer substrate at each point in each roughing groove after pretreatment is determined using a white light interferometric thickness gauge in order to generate a fine grooving etching path. Along the fine grooving etching path, a laser is used to continue fine grooving to form a crease structure.

9. The method for fabricating a foldable integrated perovskite solar cell according to claim 8, characterized in that, Several roughing grooves are formed on both sides of the polymer substrate between adjacent perovskite solar cell cells using a laser, including: Several roughing grooves are formed on the front and back sides of a polymer substrate between adjacent perovskite solar cell units using an infrared laser. The specific process parameters are as follows: the laser power is 50% of the total energy density of the infrared laser, the laser frequency is 50 kHz, the scanning speed is 100 mm / s to 200 mm / s, and the scanning spacing is 100 μm to 150 μm. Several roughing grooves with a groove depth of 75%a to 85%a and a groove width of 3a to 3.5a are formed on the front and back sides of the polymer substrate between adjacent perovskite solar cell units, where a is the thickness of the polymer substrate. Each roughing groove is pre-treated using a laser, including: Each roughing groove was pretreated using an ultraviolet laser; the specific process parameters were: ultraviolet laser pulse energy density of 5.22 J / cm². 2 The laser frequency is 500KHz, the scanning speed is 200mm / s~300mm / s, and the scanning distance is 20μm; Along the fine grooving etching path, a laser is used to continue fine grooving to form a crease structure, including: Along the fine grooving etching path, a UV laser is used to continue fine grooving to form a crease structure; the specific process parameters are: UV laser pulse energy density of 5.22 J / cm². 2 The laser frequency is 500KHz, and the scanning speed is 200mm / s~300mm / s. Finally, grooves with a depth of 89%a~91%a and a width of 3a~4a are formed on the front and back sides of the polymer substrate between adjacent perovskite solar cell units as crease structures.

10. A foldable, integrated perovskite solar cell, characterized in that, The foldable integrated perovskite solar cell is manufactured using the method described in any one of claims 1 to 9.

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