A carbon-based perovskite solar cell module, a solar cell system and application

Abstract

This application discloses a carbon-based perovskite solar cell module, solar cell system, and applications. The carbon-based perovskite solar cell module of this application includes n perovskite sub-cells and m bypass diodes, where n and m are both integers not less than 1. Each bypass diode is connected in reverse parallel with at least one perovskite sub-cell, forming a parallel bypass loop. The pins or electrode contact surfaces of the bypass diodes are simultaneously and in-situ embedded within the carbon paste during the fabrication of the carbon electrode layer. This application embeds the bypass diode wiring within the carbon electrode layer, eliminating additional metal welding and wiring processes. Electrical interconnection and physical encapsulation are directly achieved through the curing of carbon material, forming an integrated structure without external leads and stacked or adjacent to the perovskite sub-cells. This effectively alleviates the hot spot effect caused by reverse bias under shading in the carbon-based perovskite solar cell module, improving the lifespan and stability of the carbon-based perovskite solar cell module.

Description

Technical Field

[0001] This application relates to the field of perovskite battery technology, and in particular to a carbon-based perovskite solar cell module, solar cell system and its application. Background Technology

[0002] Perovskite solar cells have shown great promise in next-generation photovoltaic technology due to their advantages such as high photoelectric conversion efficiency, low manufacturing cost, and solution-processability. However, in practical applications, perovskite solar cell modules still face key bottlenecks such as insufficient operational stability and short lifespan. Especially in complex outdoor environments, issues such as partial shading, uneven illumination, and module aging mismatch can significantly affect the long-term operational reliability of the modules.

[0003] During module operation, when the output current of some sub-cells decreases due to obstruction, contamination, or performance degradation, the series connection structure forces these sub-cells into a reverse bias state, resulting in localized overheating, known as the hot spot effect. The hot spot effect not only accelerates the thermal decomposition, ion migration, and interface degradation of perovskite materials, but also causes electrode material aging and encapsulation layer failure, ultimately leading to a rapid decline in the overall module performance and severely shortening its service life.

[0004] Traditional crystalline silicon photovoltaic modules typically address hot spot issues using external junction boxes and discrete bypass diodes. However, perovskite thin-film solar cells are monolithically integrated structures. Using traditional external diodes not only requires cumbersome metal wire lead-out and soldering processes, increasing the dead zone area of ​​the module, but also the high-temperature soldering can easily cause irreversible thermal damage to the heat-sensitive perovskite layer. Therefore, the existing traditional external diode method is not suitable for perovskite solar cell modules.

[0005] In summary, how to effectively alleviate the hot spot effect caused by reverse bias in existing perovskite battery modules under shading, and improve the lifespan and stability of battery modules, remains a pressing problem to be solved in the field of perovskite battery technology. Summary of the Invention

[0006] The purpose of this application is to provide an improved carbon-based perovskite solar cell module, solar cell system, and application.

[0007] To achieve the above objectives, this application adopts the following technical solution:

[0008] One aspect of this application discloses a carbon-based perovskite solar cell module, comprising n perovskite sub-cells and m bypass diodes, where n and m are both integers not less than 1; each perovskite sub-cell includes a bottom electrode layer, a perovskite light-absorbing layer and a carbon electrode layer, and each bypass diode is connected in reverse parallel with at least one perovskite sub-cell to form a parallel bypass loop; furthermore, the pins or electrode contact surfaces of the bypass diodes are synchronously and in-situ embedded inside the carbon paste during the fabrication of the carbon electrode layer.

[0009] It should be noted that the carbon-based perovskite solar cell module of this application embeds the pins or electrode contacts of the bypass diode inside the carbon electrode layer. By utilizing the printing and co-curing characteristics of carbon paste, additional metal welding and wiring processes are eliminated. Electrical interconnection and physical encapsulation are directly achieved through the cured carbon material covering the pins or electrode contacts of the bypass diode, forming an integrated structure without external leads and physically stacked or adjacent to the corresponding perovskite sub-cells. This effectively alleviates the hot spot effect problem caused by reverse bias under shading in the carbon-based perovskite solar cell module, and improves the lifespan and stability of the carbon-based perovskite solar cell module.

[0010] In one implementation of this application, the bypass diode is integrated in the peripheral non-power generation area of ​​the perovskite sub-cell, or integrated in the gap area between adjacent perovskite sub-cells.

[0011] In one implementation of this application, the bypass diode is a Schottky diode.

[0012] In one implementation of this application, the forward voltage of the bypass diode is 0.1-50 V.

[0013] In one implementation of this application, the bypass diodes are arranged in segments according to the voltage level of the carbon-based perovskite solar cell module, such that one bypass diode is connected in reverse parallel with 1-20 perovskite sub-cells, that is, each bypass circuit covers 1-20 perovskite sub-cells.

[0014] In one implementation of this application, the two ends of the bypass diode are connected to the positive and negative terminals of the perovskite sub-cell via conductive channels or solidified carbon materials, respectively, and the connection direction is opposite to the current direction of the perovskite sub-cell.

[0015] It should be noted that in the bypass diode of this application, the pins or electrode contact surfaces are simultaneously embedded in situ inside the carbon paste during the preparation of the carbon electrode layer. After the carbon paste is cured, it forms a solidified carbon material. Since the carbon material itself is conductive, the positive and negative electrodes of the perovskite sub-cell can be connected using the solidified carbon material. It is simple and convenient to use and does not require additional lead connections.

[0016] Another aspect of this application discloses a solar cell system, which includes the carbon-based perovskite solar cell module of this application, and an intelligent protection circuit for monitoring the operating temperature of the perovskite sub-cells and controlling the selective connection of their corresponding parallel bypass diodes.

[0017] In one implementation of this application, the intelligent protection circuit includes a voltage sensor, a controllable switching element, and a control unit. The voltage sensor is used to monitor the reverse bias voltage across each perovskite sub-cell or a perovskite sub-cell group connected in parallel with the same bypass diode. The controllable switching element is connected in series with the bypass diode, with one controllable switching element corresponding to at least one bypass diode. The control unit is used to receive the reverse bias voltage value detected by the voltage sensor, and when the reverse bias voltage value exceeds a set threshold, or exceeds the set threshold for a set time, control the controllable switching element of the bypass diode connected in parallel with the perovskite sub-cell or the perovskite sub-cell group to close, connecting the parallel bypass diode.

[0018] Another aspect of this application discloses a method for improving the operational stability of a carbon-based perovskite solar cell module, comprising the following steps:

[0019] By using the carbon electrode layer printing process, the bypass diode is synchronously embedded in the carbon paste and cured, so that one bypass diode is connected in reverse parallel with at least one perovskite sub-cell to form a parallel bypass circuit.

[0020] Real-time monitoring of the electrical parameters of each perovskite sub-cell;

[0021] When the electrical parameters detected indicate that the corresponding perovskite subcell is subjected to reverse bias due to shading or failure, the bypass diode connected in parallel with the perovskite subcell is turned on, so that the current bypasses the perovskite subcell.

[0022] When the reverse bias is eliminated, the corresponding bypass diode is turned off, restoring the normal operation of the perovskite sub-cell corresponding to that bypass diode.

[0023] Another aspect of this application discloses a perovskite photovoltaic module, including the carbon-based perovskite solar cell module of this application, or the solar cell system of this application.

[0024] Due to the adoption of the above technical solutions, the beneficial effects of this application are as follows:

[0025] The carbon-based perovskite solar cell module of this application embeds the pins or electrode contacts of the bypass diode inside the carbon electrode layer. Utilizing the printing and co-curing characteristics of carbon paste, it not only eliminates the need for additional metal soldering and wiring processes, but also achieves electrical interconnection and physical encapsulation directly through the cured carbon material covering the pins or electrode contacts of the bypass diode. This forms an integrated structure without external leads and physically stacked or adjacent to the corresponding perovskite sub-cells, effectively mitigating the hot spot effect caused by reverse bias under shading in the carbon-based perovskite solar cell module, and improving the lifespan and stability of the carbon-based perovskite solar cell module. Attached Figure Description

[0026] Figure 1 This is a schematic diagram illustrating the integration of the bypass diode with the perovskite solar cell module in an embodiment of this application.

[0027] Figure 2 This is a schematic diagram of the bypass diode in an embodiment of this application;

[0028] Figure 3 This is a schematic diagram illustrating the efficiency evolution of a perovskite solar cell module with an integrated bypass diode in an embodiment of this application.

[0029] Figure 4 This is a schematic diagram illustrating the efficiency evolution of a perovskite solar cell module without integrated bypass diodes, as shown in the comparative examples of this application. Detailed Implementation

[0030] Perovskite solar cells are considered one of the most promising next-generation photovoltaic technologies due to their advantages such as high photoelectric conversion efficiency, low material cost, solution-processability, and low-temperature fabrication. In recent years, with continuous progress in material system optimization, interface engineering, and device structure design, the efficiency of small-area perovskite solar cells has exceeded 26%, and significant breakthroughs have also been achieved in the efficiency of large-area modules, demonstrating promising prospects for industrial application. However, compared with efficiency improvements, perovskite solar cell modules still have significant shortcomings in long-term operational stability and service life, becoming a key bottleneck restricting their large-scale application and commercialization.

[0031] Under actual operating conditions, perovskite solar cell modules are typically composed of multiple sub-cells connected in series or parallel to achieve higher output voltage and power. However, due to factors such as manufacturing process fluctuations, material inhomogeneity, environmental aging, and differences in operating conditions, electrical performance mismatch inevitably exists between the sub-cells. Furthermore, during outdoor applications, the module is also affected by complex factors such as partial shading, dust pollution, bird droppings, tree shade, and changes in the angle of sunlight, leading to a significant decrease in the photocurrent generated by some sub-cells.

[0032] When one or more sub-cells in a series structure have insufficient output current, the current in the entire circuit is still driven by other high-performance sub-cells. This forces the weaker or shaded cells to be in a reverse bias state, resulting in a high reverse voltage and power dissipation in that region, causing localized overheating, i.e., the hot spot effect. The hot spot effect not only causes a sharp increase in the local temperature of the module, but also triggers a series of chain degradation reactions, including thermal decomposition, phase transition and enhanced ion migration of perovskite materials, structural degradation and accelerated chemical reactions in the interface layer, electromigration and contact failure of electrode materials, thermal stress cracking and decreased barrier performance of the encapsulation layer, etc. Ultimately, this leads to rapid degradation of device performance or even irreversible failure, severely shortening the lifespan of the module.

[0033] Compared to crystalline silicon solar cells, perovskite solar cells are more sensitive to temperature, electric field, and humidity. They fail faster and undergo more complex degradation processes under reverse bias and localized high-temperature coupling. Therefore, hot spot effects have a more significant impact on the long-term stability of perovskite modules. Under actual outdoor operating conditions, without effective circuit protection measures, localized shading can cause severe performance degradation in a short period, becoming a major factor limiting the reliability of perovskite modules. Furthermore, traditional crystalline silicon modules typically use external junction boxes and discrete bypass diodes to address hot spots, requiring cumbersome metal wire leads and high-temperature soldering processes. For fully thin-film, monolithically integrated perovskite modules, the additional wiring not only increases the dead zone area, but the high-temperature soldering can also easily cause irreversible thermal damage to the heat-sensitive perovskite layer.

[0034] Therefore, there is an urgent need to develop a bypass diode structure and its collaborative working mechanism tailored to the operating characteristics of perovskite solar cell modules, so as to effectively suppress hot spot effects, reduce reverse bias and thermal stress damage under complex lighting and long-term operating conditions, thereby significantly improving the operating stability and service life of perovskite solar cell modules.

[0035] To achieve the aforementioned objectives, this application develops an improved carbon-based perovskite solar cell module, comprising n perovskite sub-cells and m bypass diodes, where n and m are both integers not less than 1. Each perovskite sub-cell includes a bottom electrode layer, a perovskite light-absorbing layer, and a carbon electrode layer. Each bypass diode is connected in reverse parallel with at least one perovskite sub-cell, forming a parallel bypass loop. Furthermore, the leads or electrode contact surfaces of the bypass diodes are synchronously and in-situ embedded within the carbon paste during the fabrication of the carbon electrode layer, such as... Figure 1 As shown.

[0036] In this application, each sub-cell is connected in series or in parallel via a conductive interconnect structure to form a module, and the back electrode of the sub-cell is a conductive carbon electrode layer; the bypass diode module is connected in parallel with the corresponding sub-cell or sub-cell group to form a bypass circuit, used to conduct bypass current when the sub-cell is reverse biased, such as... Figure 2 As shown.

[0037] In one implementation of this application, the bypass diode module is a low turn-on voltage diode structure with a forward conduction voltage of 0.1-50 V. It is arranged in segments according to the module operating voltage and the number of sub-cell cells, so that each bypass circuit covers 1-20 sub-cell cells. This allows for rapid release of the reverse bias voltage under conditions of partial obstruction or performance mismatch, thereby suppressing the generation of hot spot effect.

[0038] In one implementation of this application, the bypass diode module is embedded in situ within the carbon electrode layer, such as... Figure 1 As shown, the carbon electrode layer is simultaneously coated with carbon paste during the printing and molding process. The electrical interconnection and physical encapsulation of the bypass diode module are directly completed using the cured carbon material, forming an integrated structure without external metal leads, thereby significantly reducing wiring and soldering processes.

[0039] The bypass diode module of this application achieves electrical connection with the perovskite sub-cell unit through screen printing conductive paste, thereby being compatible with low-temperature, fully printed and flexible fabrication processes.

[0040] In one implementation of this application, the bypass diode module is integrated inside the module packaging structure, located between the barrier layer and the backplane, and forms an integrated package with the encapsulating film to reduce the synergistic erosion of the bypass structure and sub-cells by environmental moisture, oxygen and ultraviolet radiation.

[0041] In one implementation of this application, the bypass circuit adopts a multi-stage segmented structure, so that the maximum reverse bias voltage borne by each bypass segment is no higher than 0.1-50 V, thereby significantly reducing the level of local electrothermal stress.

[0042] In one implementation of this application, the bypass circuit further includes an intelligent protection circuit unit for real-time monitoring of the local temperature rise or reverse voltage change of the sub-battery unit. When the monitored value exceeds a preset threshold, the corresponding bypass diode is triggered to conduct, thereby achieving active protection.

[0043] In some possible implementations, this application provides a method for fabricating a perovskite solar cell module, comprising the following steps:

[0044] S10. Prepare a bottom electrode layer containing multiple sub-electrode regions on the substrate surface;

[0045] S20. A functional layer containing at least a perovskite layer is prepared on the bottom electrode layer, and the functional layer is scribed along the dividing line of the sub-electrode region so that the scribed position exposes the bottom electrode layer, thereby dividing the functional layer into multiple sub-functional regions corresponding to the sub-electrode regions.

[0046] S30. A carbon electrode is prepared on the surface of the functional layer. When the carbon electrode is printed using conductive carbon paste, the bypass diode is synchronously embedded in the carbon paste in the preset interconnect area or non-effective power generation area. Then, through low-temperature co-curing treatment, the bypass diode is directly realized with the carbon material to achieve solderless electrical interconnection and integrated physical packaging, thereby eliminating the need for subsequent additional component mounting, metal leads and high-temperature soldering processes.

[0047] In one implementation of this application, an optoelectronic device is provided, which includes the perovskite solar cell module described above.

[0048] The optoelectronic device of this application uses the aforementioned perovskite solar cell module. Because the module has high reliability and excellent stability, the optoelectronic device thus has higher stability and longer service life.

[0049] In some possible implementations, photovoltaic devices may take the form of solar streetlights, LED lights, solar chargers, solar panels, solar water heaters, solar power generation systems, etc. These devices utilize and store solar energy by converting it into electrical energy.

[0050] In this application, the term "and / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0051] In this application, "at least one" means one or more, and "more than one" means two or more. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or multiple items. For example, "at least one of a, b or c", or "at least one of a, b and c", can both mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, and c can be single or multiple.

[0052] It should be understood that in the various embodiments of this application, the order of the above processes does not imply the order of execution. Some or all steps may be executed in parallel or sequentially. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0053] The terminology used in the embodiments of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. The singular forms "a" and "the" as used in the embodiments of this application and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise.

[0054] The weights of the relevant components mentioned in the embodiments of this application can refer not only to the specific content of each component, but also to the proportional relationship between the weights of the components. Therefore, any scaling up or down of the content of the relevant components according to the embodiments of this application is within the scope disclosed in the embodiments of this application. Specifically, the mass described in the embodiments of this application can be a mass unit known in the chemical industry, such as µg, mg, g, or kg.

[0055] The terms "first" and "second" are used for descriptive purposes only, to distinguish objects, such as substances, from one another, and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. For example, without departing from the scope of the embodiments of this application, "first XX" may also be referred to as "second XX," and similarly, "second XX" may also be referred to as "first XX." Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of that feature.

[0056] The present application will be further described in detail below through specific embodiments. The following embodiments are only for further illustration of the present application and should not be construed as limiting the present application.

[0057] Unless otherwise specified, the technical means used in the embodiments are conventional means well known to those skilled in the art.

[0058] Example 1

[0059] A perovskite solar cell module integrates multiple perovskite solar cell units connected in series on a glass substrate. The structure of each cell unit, from bottom to top, consists of: a 100 nm thick ITO bottom electrode layer, a 50 nm thick SnO2 electron transport layer, an 800 nm thick FAPbI3 perovskite layer, a 20 nm thick P3HT hole transport layer, a 50 μm thick carbon electrode layer, and a bypass diode integrated structure.

[0060] Its preparation includes the following steps:

[0061] ① On a conductive substrate with dimensions of 30×30 cm, the ITO layer was laser scribing to divide it into 40 sub-electrode regions.

[0062] ② Preparation of the electron transport layer: Mix SnO2 colloidal aqueous dispersion with deionized water at a ratio of 1:4 and stir until homogeneous. Place the ITO substrate on the platform of a slot coater, adjust the distance between the coating head and the substrate D1 = 0.15 mm, control the coating rate V1 = 15 mm / s, and immediately transfer the SnO2 liquid film to a hot plate for annealing at a temperature F1 = 160℃ for a time T1 = 30 min to obtain the electron transport layer.

[0063] ③ Preparation of the perovskite light-absorbing layer: FAI and PbI2 were dissolved in DMF solvent in stoichiometric ratio to prepare FAPbI3 perovskite solution. The substrate with the electron transport layer already coated was placed on the platform of a slot coater. The coating head gap D2 was set to 0.12 mm and the coating rate V2 to 10 mm / s. After injecting the perovskite solution, the equipment was started. After obtaining the perovskite liquid film, it was immediately annealed on a hot plate at a temperature F2 = 150℃ for a time T2 = 30 min to obtain the perovskite light-absorbing layer.

[0064] ④ Preparation of the hole transport layer: Dissolve PTAA in chlorobenzene to prepare a solution with a concentration of 15 mg / mL. Place the substrate with the perovskite layer on the platform of a slot coater, set the coating head gap D3 = 0.12 mm, the coating rate V3 = 10 mm / s, and immediately anneal on a hot plate after coating the hole transport layer solution. The annealing temperature F3 = 120 ℃ and the time T3 = 15 min are used to obtain the hole transport layer.

[0065] ⑤ The electron transport layer, perovskite layer, and hole transport layer were scribed using a laser to divide the entire functional layer into 40 sub-functional regions. The spacing between the P2 lines and the P1 lines was 0.01 mm, and the line width was 0.3 mm.

[0066] ⑥ Graphite with a particle size of 5 μm, carbon black with a mass fraction of 20 nm (40% and 60% respectively), and carboxymethyl cellulose (viscosity 50 mPa·s) were placed in a ball mill jar, dried at 100 ℃, and then terpineol and acrylic resin were added. The mixture was ball milled for 6 h to obtain a carbon electrode slurry with good flowability. The substrate with the functional layer prepared was placed on a screen printing machine platform. A nylon screen was used, and the distance between the screen and the substrate was adjusted to 50 mm. The screen printing speed V4 = 50 mm / s was set. The carbon electrode slurry was evenly coated onto the screen, and the machine was started to complete the printing. Immediately afterwards, the substrate was annealed on a hot plate at F4 = 60 ℃ for 2 min to form a buffer protective layer approximately 3 μm thick. The substrate with the buffer protective layer prepared was placed on a screen printing machine platform, and the nylon screen was replaced with a stainless steel screen. The distance between the screen and the substrate was adjusted to 50 mm, and the screen printing speed V4 = 50 mm / s was set. The equipment was started to complete the printing process, and then immediately annealed on a hot plate at F4 = 80 ℃ for 10 min, ultimately forming a carbon electrode with a total thickness of approximately 30 μm on the surface of the buffer protective layer. The carbon electrode was then laser-etched to obtain the perovskite solar cell module.

[0067] ⑦ During the preparation of the carbon electrode, the Schottky diode (Vishay, VT2045CBP, 45V / 20A) is simultaneously embedded in situ into the carbon paste by screen printing conductive carbon paste. The electrical connection and physical encapsulation between the diode and the module sub-cell are directly achieved by the curing of the carbon paste, thereby significantly reducing the need for additional metal wiring and high-temperature welding processes. During connection, each diode and each sub-cell are connected in reverse parallel.

[0068] Example 2

[0069] A perovskite solar cell module includes multiple perovskite solar cell units connected in series on a glass substrate. The structure of each perovskite solar cell unit comprises, in sequence, a 200 nm thick FTO bottom electrode layer, a 100 nm thick TiO2 electron transport layer, and an 800 nm thick FA layer. 0.6 MA 0.4 The structure consists of a PbI3 perovskite layer, a 20 nm thick PTAA hole transport layer, a 60 μm thick carbon electrode layer, and a bypass diode integrated structure.

[0070] Its preparation includes the following steps:

[0071] ① Laser scribing was performed on the surface of the FTO layer on a 30 × 30 cm conductive substrate to form 40 sub-FTO electrode regions. Subsequently, an electron transport layer was prepared: 0.1375 g of bis(2,4-pentanedione)bis(2-propanoic acid)titanium(IV) was weighed and dissolved in 2.5 mL of n-butanol to prepare a 0.15 mol / L (acetylacetonate)diisopropyl titanate n-butanol solution. The FTO substrate was placed on a doctor blade coating platform, and the distance between the doctor blade and the substrate was adjusted to D1 = 0.12 mm. The coating speed was controlled at V1 = 12 mm / s. After obtaining the TiO2 liquid film, it was immediately transferred to a hot plate for annealing at F1 = 450℃ for T1 = 120 min, thus obtaining the electron transport layer.

[0072] ② Preparation of perovskite light-absorbing layer: FAI, MAI and PbI2 are mixed according to FAI... 0.6 MA 0.4 PbI3 was dissolved in DMF solvent in stoichiometric proportions to prepare a perovskite precursor solution. The substrate with the electron transport layer already coated was placed on the platform of a slot coater. The coating head gap D2 was set to 0.12 mm and the coating rate V2 to 15 mm / s. After injecting the perovskite solution, the equipment was started. After obtaining the liquid film, it was immediately annealed on a hot plate at a temperature F2 of 150℃ for a time T2 of 30 min to form a perovskite light-absorbing layer.

[0073] ③ Preparation of the hole transport layer: P3HT was dissolved in chlorobenzene to prepare a hole transport layer solution with a concentration of 220 mg / mL. The substrate with the perovskite layer was placed on a doctor blade coater with the blade gap D3 = 0.12 mm and the coating speed V3 = 12 mm / s set. After coating the hole transport layer solution, it was immediately annealed on a hot plate at a temperature F3 = 120 ℃ for a time T3 = 20 min to obtain the hole transport layer.

[0074] ④ A laser is used to scribing the electron transport layer, perovskite layer, and hole transport layer with P2 lines, dividing the entire functional layer into 40 sub-functional regions. The spacing between the P2 lines and the P1 lines is 0.05 mm, and the line width is 0.3 mm.

[0075] ⑤ Graphite with a particle size of 5 μm, carbon black with a mass fraction of 20 nm (40% and 60% respectively), and carboxymethyl cellulose (viscosity 50 mPa·s) were placed in a ball mill jar, dried at 100 ℃, and then terpineol and acrylic resin were added. The mixture was ball milled for 6 h to obtain a carbon electrode slurry with good flowability. The substrate with the functional layer prepared was placed on a screen printing machine platform. A nylon screen was used, and the distance between the screen and the substrate was adjusted to 50 mm. The screen printing speed V4 = 50 mm / s was set. The carbon electrode slurry was evenly coated onto the screen, and the machine was started to complete the printing. Immediately afterwards, the substrate was annealed on a hot plate at F4 = 60 ℃ for 2 min to form a buffer protective layer approximately 3 μm thick. The substrate with the buffer protective layer prepared was placed on a screen printing machine platform, and the nylon screen was replaced with a stainless steel screen. The distance between the screen and the substrate was adjusted to 50 mm, and the screen printing speed V4 = 50 mm / s was set. The equipment was started for printing, with five printing passes. Immediately afterwards, the surface was annealed on a hot plate at F4 = 80 °C for 10 min, ultimately forming a carbon electrode with a total thickness of approximately 50 μm on the surface of the buffer protective layer. The carbon electrode was then laser-etched to obtain the perovskite solar cell module.

[0076] ⑥ During the preparation of the carbon electrode, the Schottky diode (Vishay, VT2045CBP, 45V / 20A) is simultaneously embedded in situ into the carbon paste by screen printing conductive carbon paste. The electrical connection and physical encapsulation of the diode and the module sub-cell are directly achieved by using carbon paste curing, thereby significantly reducing additional metal wiring and high-temperature welding processes; during connection, each diode and each sub-cell are connected in reverse parallel.

[0077] Examples 3-5

[0078] The difference between Embodiments 3-5 and Embodiment 1 is that the breakdown voltage and current of the Schottky diodes are 45V / 30A (HY Electronics, SS12 SMA) (Embodiment 3), 45V / 25A (HY Electronic Corp, 25PV045) (Embodiment 4), and 30V / 15A (Texas Instruments, SM74611KTTR) (Embodiment 5), respectively. Except for the bypass diode, they are the same as in Embodiment 1.

[0079] Comparative Example 1

[0080] This comparative example provides a method for fabricating a large-area perovskite solar cell module. The only difference between this method and Example 1 is that it does not integrate a bypass diode structure; otherwise, it is the same as Example 1.

[0081] The following performance tests were performed on the above embodiments and comparative examples:

[0082] 1. Outdoor environmental operation tests were conducted on the perovskite battery module prepared in Example 1, and its efficiency evolution over time is as follows: Figure 3 As shown.

[0083] 2. Outdoor environmental operation tests were conducted on the perovskite battery module prepared in Comparative Example 1, and its efficiency evolution over time is as follows: Figure 4 As shown.

[0084] The test results show that, by adopting the bypass diode integrated structure in this embodiment, the reverse bias problem caused by the shading effect in outdoor environments is effectively alleviated. After 30 days of continuous outdoor operation, the photoelectric conversion efficiency shows almost no degradation, demonstrating excellent operational stability. Figure 3 As shown. In contrast, Comparative Example 1, due to the lack of the bypass diode integrated structure of this application, exhibited significant hot spot effects during outdoor operation. Infrared thermal imaging showed local temperatures exceeding 85°C. By the 12th day of operation, some sub-cells had already experienced irreversible failure, and the module's output power had decreased to below 80% of its initial value. Figure 4 As shown, this leads to overall device failure. The perovskite battery modules of Examples 2 to 5 underwent the same outdoor environmental operation test. The test results showed that after 30 days of continuous outdoor operation, the photoelectric conversion efficiency of the perovskite battery modules of Examples 2 to 5 showed almost no decay, exhibiting operational stability comparable to that of the perovskite battery module of Example 1.

[0085] In summary, the technical solution of this application can significantly alleviate the hot spot effect of perovskite modules during outdoor operation, thereby improving their service life and having great significance for improving the reliability of perovskite solar cell modules in practical applications.

[0086] The above description, in conjunction with specific embodiments, provides a further detailed explanation of this application and should not be construed as limiting the specific implementation of this application to these descriptions. Those skilled in the art to which this application pertains can make several simple deductions or substitutions without departing from the concept of this application.

Claims

1. A carbon-based perovskite solar cell module, characterized in that: It includes n perovskite sub-cells and m bypass diodes, where n and m are both integers not less than 1; Each perovskite sub-cell includes a bottom electrode layer, a perovskite light-absorbing layer, and a carbon electrode layer. Each bypass diode is connected in reverse parallel with at least one perovskite sub-cell to form a parallel bypass loop. Furthermore, the pins or electrode contact surfaces of the bypass diodes are synchronously and in situ embedded inside the carbon paste during the fabrication of the carbon electrode layer.

2. The carbon-based perovskite solar cell module according to claim 1, characterized in that: The bypass diode is integrated in the peripheral non-power generation area of ​​the perovskite sub-cell, or in the gap area between adjacent perovskite sub-cells.

3. The carbon-based perovskite solar cell module according to claim 1, characterized in that: The bypass diode is a Schottky diode.

4. The carbon-based perovskite solar cell module according to claim 1, characterized in that: The bypass diode has a forward voltage of 0.1-50 V.

5. The carbon-based perovskite solar cell module according to claim 1, characterized in that: The bypass diodes are arranged in segments according to the voltage level of the carbon-based perovskite solar cell module, so that one bypass diode is connected in reverse parallel with 1-20 perovskite sub-cells, that is, each bypass circuit covers 1-20 perovskite sub-cells.

6. The carbon-based perovskite solar cell module according to any one of claims 1-5, characterized in that: The two ends of the bypass diode are connected to the positive and negative terminals of the perovskite sub-cell via conductive channels or solidified carbon material, respectively, and the connection direction is opposite to the current direction of the perovskite sub-cell.

7. A solar cell system, characterized in that: The invention includes a carbon-based perovskite solar cell module as described in any one of claims 1-6, and an intelligent protection circuit for monitoring the operating temperature of the perovskite sub-cells and controlling the selective connection of their corresponding parallel bypass diodes.

8. The solar cell system according to claim 7, characterized in that: The intelligent protection circuit includes a voltage sensor, a controllable switching element, and a control unit; The voltage sensor is used to monitor the reverse bias voltage across each perovskite subcell or a perovskite subcell group connected in parallel with the same bypass diode. The controllable switching element is connected in series with the bypass diode, and one controllable switching element corresponds to at least one bypass diode; The control unit is used to receive the reverse bias value detected by the voltage sensor, and when the reverse bias value exceeds a set threshold, or exceeds the set threshold for a set time, it controls the controllable switching element of the bypass diode connected in parallel with the perovskite sub-cell or the perovskite sub-cell group to close, and connects the bypass diode in parallel.

9. A method for improving the operational stability of a carbon-based perovskite solar cell module, characterized in that: Includes the following steps, By using the carbon electrode layer printing process, the bypass diode is synchronously embedded in the carbon paste and cured, so that one bypass diode is connected in reverse parallel with at least one perovskite sub-cell to form a parallel bypass circuit. Real-time monitoring of the electrical parameters of each perovskite sub-cell; When the electrical parameters detected indicate that the corresponding perovskite subcell is subjected to reverse bias due to shading or failure, the bypass diode connected in parallel with the perovskite subcell is turned on, so that the current bypasses the perovskite subcell. When the reverse bias is eliminated, the corresponding bypass diode is turned off, restoring the normal operation of the perovskite sub-cell corresponding to that bypass diode.

10. A perovskite photovoltaic module, characterized in that: It includes the carbon-based perovskite solar cell module according to any one of claims 1-6, or the solar cell system according to claim 7 or 8.

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