A method for predicting and evaluating optical performance of photoluminescence high-transmittance photovoltaic coating

Abstract

The application discloses a photoluminescence high-transmittance photovoltaic coating optical performance prediction and evaluation method, which tests optical absorption characteristics of selected photoluminescence materials, tests fluorescence emission characteristics, verifies suitable particle size, doping amount and thickness, prepares a coating, tests the coating, calculates a theoretical photoelectric conversion efficiency gain of the coating, calculates an actual photoelectric conversion efficiency correction coefficient, and applies the correction coefficient to transmittance fluorescence spectra of other kinds of photoluminescence coatings to predict and evaluate photovoltaic cell efficiency improvement and photoluminescence material application performance. The application can analyze and evaluate how to select photoluminescence filler types and coating preparation design and optical performance test according to different functions and fluorescence performance of photoluminescence fillers, different polymer matrix resins and various photovoltaic cells, and provide basic data for machine learning calculation of the best formula of the photoluminescence material in the coating.

Description

Technical Field

[0001] This invention relates to the field of photovoltaic technology, specifically a method for predicting and evaluating the optical performance of photoluminescent high-transmittance photovoltaic coatings. Background Technology

[0002] Photovoltaic cells are one of the main applications of solar energy. Although silicon-based photovoltaic cells are widely used, the low utilization rate of solar energy and the impact of long-term ultraviolet radiation on the stability of photovoltaic devices limit the further development of the photovoltaic industry. Introducing photoluminescent fillers into the resin matrix of coatings, while maintaining high transmittance and good fluorescence performance, is a simple and readily available method. However, the wide variety of photoluminescent fillers, the diverse coating options available from different polymer matrix resins, and the diverse types of photovoltaic cells mean that research on coating preparation processes and prediction and evaluation methods is still incomplete. This leads to problems such as poor application results and high experimental costs in the application of photoluminescent fillers. Therefore, analyzing and evaluating how to select photoluminescent materials, design coating preparation, and conduct optical performance testing for different functional photoluminescent fillers, different polymer matrix resins, and diverse photovoltaic cell types, and providing basic data for further machine learning calculations of the optimal formulation of photoluminescent materials in coatings, is an urgent technical problem to be solved. Summary of the Invention

[0003] Purpose of the invention: To solve related technical problems, this invention provides a photoluminescent high-transmittance photovoltaic coating, its preparation, and an optical performance evaluation method.

[0004] Technical solution: The present invention provides a method for predicting and evaluating the optical performance of photoluminescent high-transmittance photovoltaic coatings, comprising the following steps:

[0005] A. Test the optical absorption characteristics of the selected photoluminescent material to determine its ultraviolet absorption response band, and test its fluorescence emission characteristics under the action of the ultraviolet wavelength with the strongest absorption.

[0006] B. Under the condition of a slit width of 0.3 / 0.5 nm in a fluorescence spectrometer, screen for emission fluorescence signal intensities not less than 10. 6 The photoluminescent material of cps was used to obtain suitable particle size, doping amount and thickness through simulation and experimental verification. The particle size was controlled within the range of 250-1000 nm and the coating thickness was controlled within the range of 4-6 μm. The coating was prepared according to this method.

[0007] C. The optical transmission properties and fluorescence transmission properties of the coating prepared in step B are tested.

[0008] D. The measured transmitted fluorescence spectrum curves are convolved with the response curves of different types of photovoltaic cells to calculate the theoretical photoelectric conversion efficiency gain of the coating.

[0009] E. Compare the actual photoelectric conversion efficiency gain with that of different types of coatings, and calculate the actual photoelectric conversion efficiency correction coefficient k value;

[0010] F. The obtained k value is applied to the transmitted fluorescence spectrum of other types of photoluminescent coatings to predict and evaluate the improvement of photovoltaic cell efficiency and the application performance of photoluminescent materials.

[0011] Preferably, the theoretical photoelectric conversion efficiency gain of the coating is obtained by convolving and integrating the transmitted fluorescence spectrum curve of the coating with the battery response curve.

[0012]

[0013]

[0014] In equations (1)-(2), E Q ε(λ) represents the response curve value of a P-type photovoltaic cell; ε(λ) represents the energy of a photon at different wavelengths; Δt(λ) represents the spectral change at different wavelengths; h is Planck's constant; and c is the speed of light.

[0015] The gain relationship between the transmitted fluorescence spectrum curve of the coating and the battery response curve and battery efficiency is calculated using a function to calculate the actual photoelectric conversion efficiency correction coefficient k value.

[0016]

[0017]

[0018] ΔE cell =η2-η1 (5)

[0019] In equations (3)-(5): k is the correction coefficient; Δt is the spectral change at different wavelengths; ΔE cell η represents the change in photovoltaic efficiency of the P-type photovoltaic cell; η represents the photovoltaic efficiency of the photovoltaic cell; η1 represents the initial photovoltaic efficiency of the photovoltaic cell; η2 represents the photovoltaic efficiency of the photovoltaic cell after gain; the correction coefficient k value of the gain of the actual photoelectric conversion efficiency of different types of coatings is obtained by calculation.

[0020] Preferably, the coating material comprises, by weight percentage, the following components: 99.8-99.9% polymer-based resin, 1-2‰ organic photoluminescent filler, or 1-2‰ inorganic photoluminescent filler.

[0021] Preferably, the photoluminescent filler is one of inorganic or organic downconversion, upconversion, plasma, long afterglow, or other photoluminescent materials.

[0022] Preferably, the polymer-based resin is PG resin, waterborne polyurethane, waterborne acrylic, waterborne fluorocarbon resin, etc.

[0023] Preferably, the coating is prepared by the following steps:

[0024] (1) Grind the inorganic photoluminescent filler or the organic photoluminescent filler to make the particle size of the filler reach 250-1000nm;

[0025] (2) The inorganic or organic photoluminescent filler obtained in step (1) is mixed with polymer-based resin according to the mass percentage, and then placed in an ultrasonic disperser for ultrasonication to obtain a uniformly dispersed coating.

[0026] (3) The coating obtained in step (2) is used to prepare a photoluminescent high-transmittance coating on the upper surface of the photovoltaic cell by spraying, coating, spin coating and other processes.

[0027] Preferably, the organic photoluminescent filler is ground at room temperature for 2-4 hours; the inorganic photoluminescent filler is ground at room temperature for 4-6 hours.

[0028] Beneficial effects: The prediction and evaluation method of this invention can analyze and evaluate how to select the type of photoluminescent material and design the coating preparation, as well as the optical performance testing, for photoluminescent fillers with different functions and fluorescence properties, different polymer matrix resins, and various types of photovoltaic cells. This provides basic data for the next step of machine learning to calculate the optimal formulation of photoluminescent materials in the coating. Attached Figure Description

[0029] Figure 1 The graph shows the effect of different particle sizes of the orange photoluminescent material (Y2O2S:Eu) in Example 1 on the transmittance of the photoluminescent high-transmittance photovoltaic coating.

[0030] Figure 2 Example 2 shows the effect of different volumetric doping amounts of the photoluminescent material orange (Y2O2S:Eu) on the transmittance of the photoluminescent high-transmittance photovoltaic coating at a particle size of 0.500 μm (particle size of 1000 nm).

[0031] Figure 3 The transmittance curves of the photoluminescent coatings under different mass doping amounts (1-5‰) in Example 2 are shown.

[0032] Figure 4The fluorescence emission and excitation spectrum of the orange (Y2O2S:Eu) photoluminescent material in Example 3 is shown in the figure.

[0033] Figure 5 The image shows the transmittance and transmittance fluorescence curves of the coating in Example 3.

[0034] Figure 6 This is a graph showing the photovoltaic efficiency variation of the orange (Y2O2S:Eu) coating in Example 3.

[0035] Figure 7 The fluorescence emission and excitation spectra of Eu(TTA)3phen, the photoluminescent material of Example 4, are shown in the figure.

[0036] Figure 8 The image shows the transmittance and transmittance fluorescence curves of the coating in Example 4.

[0037] Figure 9 This is a graph showing the photovoltaic efficiency variation of the Eu(TTA)3phen coating in Example 4;

[0038] Figure 10 These are the photovoltaic cell response curves and photovoltaic cell spraying test schematic diagrams for Examples 3 and 4. Detailed Implementation

[0039] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0040] This invention provides a method for predicting and evaluating the optical performance of photoluminescent high-transmittance photovoltaic coatings, comprising the following steps:

[0041] A. Perform optical absorption characteristic tests on the selected photoluminescent material to determine its ultraviolet absorption response band, and test its fluorescence emission characteristics under the action of the ultraviolet wavelength with the strongest absorption; specifically, optical absorption characteristic testing refers to measuring the absorption curve of the material using an ultraviolet-visible spectrophotometer.

[0042] B. Under the conditions of a slit size of 0.3 / 0.5 nm in fluorescence spectrometry, select candidates with emission fluorescence signal intensities not less than 10. 6 The photoluminescent material of cps was used to obtain suitable particle size, doping amount and thickness through simulation and experimental verification. The particle size was controlled within the range of 250-1000 nm and the coating thickness within the range of 4-6 μm. The coating was prepared according to this method. The simulation was carried out by FDTD optical transmittance simulation of coatings with different particle sizes and doping amounts of fillers. The experimental verification was carried out by preparing coatings with different composite filler particle sizes. The optimal particle size was determined by comparing the transmittance and then the optimal doping amount under the optimal particle size was studied.

[0043] C. The optical transmittance and fluorescence transmittance characteristics of the coating prepared in step B are tested. Specifically, the transmittance of the coating is monitored by a UV-Vis spectrophotometer and the fluorescence transmittance characteristics of the coating are collected by a fiber optic spectrometer.

[0044] D. The measured transmitted fluorescence spectrum curves are convolved with the response curves of different types of photovoltaic cells to calculate the theoretical photoelectric conversion efficiency gain of the coating.

[0045] E. Compare the actual photoelectric conversion efficiency gain with that of different types of coatings, and calculate the actual photoelectric conversion efficiency correction coefficient k value;

[0046] F. The obtained k value is applied to the transmitted fluorescence spectrum of other types of photoluminescent coatings to predict and evaluate the improvement of photovoltaic cell efficiency and the application performance of photoluminescent materials.

[0047] In the above steps, the transmission fluorescence spectrum curve of the coating is convolved with the battery response curve to calculate the theoretical photoelectric conversion efficiency gain of the coating as a function:

[0048]

[0049]

[0050] In equations (1)-(2), E Q ε(λ) represents the response curve value of a P-type photovoltaic cell; ε(λ) represents the energy of a photon at different wavelengths; Δt(λ) represents the spectral change at different wavelengths; h is Planck's constant; and c is the speed of light.

[0051] The gain relationship between the transmitted fluorescence spectrum curve of the coating and the battery response curve and battery efficiency is calculated using a function to calculate the actual photoelectric conversion efficiency correction coefficient k value.

[0052]

[0053]

[0054] ΔE cell =η2-η1 (5)

[0055] In equations (3)-(5): k is the correction coefficient; Δt is the spectral change at different wavelengths; ΔE cell η represents the change in photovoltaic efficiency of the P-type photovoltaic cell; η represents the photovoltaic efficiency of the photovoltaic cell; η1 represents the initial photovoltaic efficiency of the photovoltaic cell; η2 represents the photovoltaic efficiency of the photovoltaic cell after gain; the correction coefficient k value of the gain of the actual photoelectric conversion efficiency of different types of coatings is obtained by calculation.

[0056] To facilitate explanation of the technical solution of this invention, the coating used in the technical solution of this invention is first described. The coating, by mass percentage, comprises: 99.8-99.9% polymer-based resin and 1-2‰ inorganic photoluminescent filler, or 99.8-99.9% polymer-based resin and 1-2‰ organic photoluminescent filler. The inorganic photoluminescent filler may be at least one of orange (Y₂O₂S:Eu) or yellow (Y₂O₂S:Eu&ZnS:Cd) photoluminescent fluorescent materials, and the organic photoluminescent filler may be at least one of Eu(TTA)₃phen or Eu(TTA)₂AAphen photoluminescent fluorescent materials. The polymer-based resin is PG resin. The above coating is prepared by the following method:

[0057] (1) Grind the inorganic photoluminescent filler or the organic photoluminescent filler to make the particle size of the filler reach 250-1000nm;

[0058] (2) The inorganic or organic photoluminescent filler obtained in step (1) is mixed with polymer-based resin according to the mass percentage, and then placed in an ultrasonic disperser for ultrasonication to obtain a uniformly dispersed coating.

[0059] (3) The coating obtained in step (2) is used to prepare a photoluminescent high-transmittance coating on the upper surface of the photovoltaic cell by spraying, coating, spin coating and other processes.

[0060] The organic photoluminescent filler was ground at room temperature for 2-4 hours; the inorganic photoluminescent filler was ground at room temperature for 4-6 hours.

[0061] Example 1

[0062] This embodiment provides a method for predicting and evaluating the optical performance of photoluminescent high-transmittance photovoltaic coatings, including the following steps:

[0063] (1) Eight different particle sizes (r = 0.125, 0.200, 0.250, 0.300, 0.375, 0.500, 1.000, 2.000 μm) were selected, and the influence of different particle sizes on the transmittance of the photoluminescent high-transmittance photovoltaic coating was studied using FDTD optical simulation software;

[0064] (2) The optimal volumetric doping standard (4‰, taking the orange sample No. 1 as an example, which is converted to a solid content of 1.674‰) under different particle sizes was selected, and the influence of different particle sizes (r=0.125, 0.200, 0.250, 0.300, 0.375, 0.400, 0.450, 0.500, 1.000, 2.000μm) on the transmittance of the photoluminescent high-transmittance photovoltaic coating was further studied.

[0065] Figure 1 This is a graph showing the effect of different particle sizes of the orange photoluminescent material (Y₂O₂S:Eu) in Example 1 on the transmittance of the high-transmittance photoluminescent photovoltaic coating. Through Example 1, the simulation results show that, under a volume doping standard of 4‰, the coating composed of the photoluminescent filler and the polymer-based resin maintains the best transmittance performance when the particle size is in the range of 0.125-0.500 μm (particle size 250-1000 nm).

[0066] Example 2

[0067] This embodiment provides a method for predicting and evaluating the optical performance of photoluminescent high-transmittance photovoltaic coatings, including the following steps:

[0068] (1) Using FDTD optical simulation software, under the standard of 4‰ volume doping and particle size in the range of 0.125-0.500μm, the influence of the volume doping of photoluminescent filler on the transmittance of the coating was further studied (without considering the dispersion of filler in the coating).

[0069] (2) Based on the simulation results in step (1), coatings with mass doping of 1-5‰ (volume doping of 2.4-11.9‰) were prepared respectively, and the influence of the volume doping of photoluminescent filler on the transmittance of the coating was experimentally verified.

[0070] Figure 2 This is a graph showing the effect of different volumetric doping amounts of the photoluminescent material orange (Y2O2S:Eu) on the transmittance of the photoluminescent high-transmittance photovoltaic coating at a particle size of 0.500 μm (particle size of 1000 nm). Figure 3 This is a transmittance curve of the photoluminescent coating under different mass doping concentrations of 1-5‰. Through Example 2, under simulation and experimental verification, without considering the dispersion of filler in the coating, the volume doping concentration of photoluminescent filler can reach 4-10‰; the optimal mass doping concentration combined with the experiment is 2‰ (volume doping concentration of 4.8‰), which is consistent with the simulation results. The relative (transparent glass) transmittance ΔT of the photoluminescent high-transmittance photovoltaic coating is 99.22%-100.55%.

[0071] Example 3

[0072] This embodiment provides a method for predicting and evaluating the optical performance of photoluminescent high-transmittance photovoltaic coatings, including the following steps:

[0073] (1) Weigh 2g of orange (Y2O2S:Eu) inorganic photoluminescent filler, add it to a ball mill and ball mill it with deionized water to obtain ball mill slurry. The ball milling time is 4-6h, the ball milling speed is 300rpm, and the ball milling temperature is 25℃.

[0074] (2) The slurry obtained in step (1) is dried, dried and ground. 0.02g of orange (Y2O2S:Eu) and 9g of PG resin are mixed according to the mass percentage and then placed in an ultrasonic disperser for ultrasonication to obtain a uniformly dispersed coating.

[0075] (3) The coating obtained in step (2) is used to prepare a photoluminescent high-transmittance coating on the upper surface of the photovoltaic cell by spraying process, and the coating thickness ranges from 4 to 6 μm.

[0076] (4) The fluorescence and transmittance properties, transmittance and photovoltaic cell efficiency of the photoluminescent coating are tested. The theoretical photoelectric conversion efficiency gain of the coating is obtained by convolution integral calculation of the fluorescence spectrum curve of the coating and the response curve of the silicon-based photovoltaic cell. The photoelectric conversion efficiency gain of the coating is compared with that of the orange coating, and the actual photoelectric conversion efficiency correction coefficient k1 is calculated.

[0077] (5) Apply the k1 value obtained in step (4) to the transmitted fluorescence spectrum of other types of photoluminescent coatings to predict the performance of photoluminescent materials in photovoltaic cells, avoid poor application results and unnecessary experimental losses. The whole process can form a complete evaluation system for the performance of photoluminescent materials and coatings.

[0078] Figure 4 This is a fluorescence emission and excitation spectrum curve of the orange (Y2O2S:Eu) photoluminescent material in Example 3. Figure 5 This is a graph showing the transmittance and fluorescence transmission of the coating in Example 3. Figure 6 This is a graph showing the photovoltaic efficiency variation of the orange (Y2O2S:Eu) coating. Through Example 3, under our designed formulation and prediction and evaluation methods, the coating resulting from the composite of inorganic photoluminescent filler and PG resin maintains high transmittance and light conversion properties.

[0079] Example 4

[0080] This embodiment provides a method for predicting and evaluating the optical performance of photoluminescent high-transmittance photovoltaic coatings, including the following steps:

[0081] (1) Weigh 2g of Eu(TTA)3phen organic photoluminescent filler and add it to a sand mill to be sand milled with ethanol to obtain sand mill slurry. The sand milling time is 2-4 hours, the sand milling speed is 2000-2500 rpm, and the sand milling temperature is room temperature.

[0082] (2) Calculate the concentration of the slurry obtained in step (1), mix 0.2g of Eu(TTA)3phen with 9g of PG resin by mass percentage, and then put it into an ultrasonic disperser for ultrasonication to obtain a uniformly dispersed coating.

[0083] (3) The coating obtained in step (2) is used to prepare a photoluminescent high-transmittance coating on the upper surface of the photovoltaic cell by spraying process, and the coating thickness ranges from 4 to 6 μm.

[0084] (4) The fluorescence and transmittance properties, transmittance and photovoltaic cell efficiency of the photoluminescent coating are tested. The theoretical photoelectric conversion efficiency gain of the coating is obtained by convolution integral calculation of the fluorescence spectrum curve of the coating and the response curve of the silicon-based photovoltaic cell. The correction coefficient k1 of the orange (Y2O2S:Eu) coating is applied to the TTA coating to obtain the predicted photovoltaic efficiency improvement. The predicted efficiency improvement is then compared with the photoelectric conversion efficiency gain of the TTA coating. The actual photoelectric conversion efficiency correction coefficient k2 value is calculated.

[0085] (5) Apply the obtained k1 and k2 values ​​to the transmitted fluorescence spectrum of other types of photoluminescent coatings to predict the performance of photoluminescent materials in photovoltaic cells, avoid poor application results and unnecessary experimental losses. The whole process can form a complete evaluation system for the performance of photoluminescent materials and coatings.

[0086] Figure 7 This is a fluorescence emission and excitation spectrum curve of Eu(TTA)3phen, the photoluminescent material of Example 3. Figure 8 This is a graph showing the transmittance and fluorescence transmission of the coating in Example 4. Figure 9 This is a graph showing the photovoltaic efficiency variation of the Eu(TTA)3phen coating. Through Example 4, under our designed formulation and prediction and evaluation methods, the coating resulting from the composite of organic photoluminescent filler and PG resin maintains high transmittance and good light conversion characteristics.

[0087] The filler size r required for the photoluminescent high-transmittance coatings simulated in Examples 1 and 2 is 0.125-0.500 μm. Without considering the dispersion of the filler in the coating, the maximum doping amount can reach 1%.

[0088] The photoluminescent high-transmittance coatings obtained in Examples 3 and 4 were tested for their (transmittance) fluorescence performance using a fluorescence spectrometer and a fiber optic spectrometer. The fluorescence spectrometer test conditions were set as follows: excitation wavelength of 365 nm, emission band of 400-700 nm, and slit width of 0.3 / 0.5. The fiber optic spectrometer test conditions were set as full-spectrum light excitation.

[0089] Examples 3 and 4 involve the addition of inorganic or organic photoluminescent fillers. These formulations are not the final solutions of this invention, but are intended to illustrate that, under our designed formulations and prediction and evaluation methods, the combination of inorganic or organic photoluminescent fillers with PG resin is beneficial to improving solar energy utilization and photovoltaic efficiency.

[0090] Figure 1 It can be seen that, under the standard of the optimal doping amount of 4‰, the filler size r required for the photoluminescent high transmittance coating is 0.125-0.500μm.

[0091] Figure 2-3 It can be seen that, with a particle size of 0.500 μm, without considering the dispersion of fillers in the coating, the volume doping of photoluminescent fillers can reach 4-10‰; the optimal mass doping based on the experiment is 2‰ (volume doping is 4.8‰), which is consistent with the simulation results. The relative (transparent glass) transmittance ΔT of the photoluminescent high-transmittance photovoltaic coating is 99.22%-100.55%.

[0092] Figure 4 It can be seen that the orange (Y2O2S:Eu) inorganic photoluminescent filler possesses a high and broad ultraviolet absorption band outside the photovoltaic cell response band, a high and broad emission fluorescence signal within the photovoltaic cell response band, and its excitation band avoids overlap with the utilized (visible) band as much as possible.

[0093] Figure 5-6 It can be seen that adding orange (Y2O2S:Eu) phosphor to PG resin, after ball milling and ultrasonic dispersion, results in a coating with a relative (transparent glass) transmittance ΔT of 99.22%-100.55% at room temperature, and the fluorescence transmission performance is improved. The theoretical photoelectric conversion efficiency gain of the coating is obtained by convolving the fluorescence transmission spectrum curve of the coating with the response curve of the silicon-based photovoltaic cell. Compared with the photoelectric conversion efficiency gain of the orange coating, the coating can improve the efficiency of polycrystalline silicon photovoltaic cells by up to 0.1219%. The actual photoelectric conversion efficiency correction coefficient k1 is calculated to be 0.0222, meaning that the utilization rate of photon energy gained by the coating is 2.22%. The obtained k1 value is applied to the fluorescence transmission spectra of other types of photoluminescent coatings to predict the excellent performance of photoluminescent materials in photovoltaic cells, avoiding poor application results and unnecessary experimental losses. This study analyzes and evaluates the selection of photoluminescent materials, coating design, and optical performance testing for different functional photoluminescent fillers, different polymer matrix resins, and various types of photovoltaic cells. This provides basic data for the next step of machine learning to calculate the optimal formulation of photoluminescent materials in the coating.

[0094] Figure 7 It can be seen that Eu(TTA)3phen organic photoluminescent filler has a high and wide ultraviolet absorption band outside the photovoltaic cell response band, a high and wide emission fluorescence signal within the photovoltaic cell response band, and the excitation band avoids overlap with the utilized (visible) band as much as possible.

[0095] Figure 8-9It can be seen that adding Eu(TTA)3phen to PG resin, after sand milling and ultrasonic dispersion, and preparing the coating at room temperature, results in a relative (transparent glass) transmittance ΔT of 99.22%-100.55%, and improves fluorescence transmission performance. The theoretical photoelectric conversion efficiency gain of the coating is obtained by convolving the fluorescence spectrum curve of the coating with the response curve of the silicon-based photovoltaic cell. Applying the correction coefficient k1 of the orange (Y2O2S:Eu) coating to the TTA coating yields a predicted photovoltaic efficiency improvement of up to 0.4022%. Comparing this with the photoelectric conversion efficiency gain of the TTA coating, the coating improves the efficiency of polycrystalline silicon photovoltaic cells by up to 0.2767%, indicating a significant difference between the two. The discrepancy indicates that the correction coefficient k2 of the TTA coating differs from that of the orange (Y2O2S:Eu) coating. Therefore, the actual photoelectric conversion efficiency correction coefficient k2 value was calculated. The calculated value of correction coefficient k2 is 0.0366, meaning that the utilization rate of the gain photon energy by this coating is 3.66%. Compared with the correction coefficient k1 of the orange (Y2O2S:Eu) coating, it can be seen that the correction coefficient fluctuates within the same order of magnitude range. The obtained k2 is greater than k1, indicating that the utilization rate of gain photons by the TTA coating is higher than that of the orange coating. This serves as an evaluation index for the comprehensive performance (including the light conversion performance and transmittance performance) of coatings prepared under different conditions. The obtained k1 and k2 values ​​are applied to the transmitted fluorescence spectra of other types of photoluminescent coatings to predict the performance of photoluminescent materials in photovoltaic cells, avoiding poor application results and unnecessary experimental losses. This study analyzes and evaluates the selection of photoluminescent materials, coating design, and optical performance testing for different functional photoluminescent fillers, different polymer matrix resins, and various types of photovoltaic cells. This provides basic data for the next step of machine learning to calculate the optimal formulation of photoluminescent materials in the coating.

[0096] Figure 10 The figures shown are the photovoltaic cell response curves and the photovoltaic cell spraying test diagrams for Examples 3 and 4, respectively.

[0097] In each embodiment, the solid content of the PG resin is 12.5%.

[0098] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for predicting and evaluating the optical performance of photoluminescent high-transmittance photovoltaic coatings, characterized in that, Includes the following steps: A. Perform optical absorption characteristic tests on the selected photoluminescent materials to determine their ultraviolet absorption response band, and test their fluorescence emission characteristics under the ultraviolet wavelength of strongest absorption; B. Under the conditions of a slit of 0.3 / 0.5 nm in a fluorescence spectrometer, screen materials with fluorescence emission signal intensities not less than 10 6 The photoluminescent material of CPS is prepared by grinding inorganic or organic photoluminescent fillers to achieve a particle size of 250-1000 nm. The obtained inorganic or organic photoluminescent fillers are mixed with polymer-based resin by mass percentage and ultrasonically dispersed in an ultrasonic disperser to obtain a uniformly dispersed coating. The coating is then applied to the upper surface of a photovoltaic cell using spraying, coating, or spin coating processes to obtain the photoluminescent high-transmittance photovoltaic coating with a thickness of 4-6 μm. C. The optical transmittance and transmittance fluorescence characteristics of the coating prepared in step B are tested. D. The measured transmittance fluorescence spectrum curve is convolved with the response curves of different types of photovoltaic cells to calculate the theoretical photoelectric conversion efficiency gain of the coating for different types of photovoltaic cells. E. The theoretical photoelectric conversion efficiency gain of the coating obtained in step D for different types of photovoltaic cells is compared with the actual photovoltaic cell efficiency change characterized by the difference between the measured initial photovoltaic cell efficiency and the photovoltaic cell efficiency after gain. The actual photovoltaic cell efficiency change is divided by the theoretical photoelectric conversion efficiency gain to obtain the actual photoelectric conversion efficiency correction coefficient k value corresponding to the coating. F. The obtained k value is applied to the transmitted fluorescence spectrum of other types of photoluminescent coatings to predict and evaluate the improvement of photovoltaic cell efficiency and the application performance of photoluminescent materials.

2. The method for predicting and evaluating the optical performance of photoluminescent high-transmittance photovoltaic coatings according to claim 1, characterized in that: The theoretical photoelectric conversion efficiency gain of the coating is obtained by convolving and integrating the transmitted fluorescence spectrum curve of the coating with the battery response curve. （1） （2） In equations (1)-(2), E Q ε(λ) represents the response curve value of a P-type photovoltaic cell; ε(λ) represents the energy of a photon at different wavelengths. denoted as spectral variation at different wavelengths; h is Planck's constant; c is the speed of light; the calculation function for the gain relationship between the transmitted fluorescence spectrum curve of the coating, the battery response curve, and the battery efficiency is used to calculate the actual photoelectric conversion efficiency correction coefficient k value. （3） （4） （5） In equations (3)-(5): k is a correction coefficient, which is the ratio of the gain in battery efficiency to the change in photon energy; The amount of spectral change at different wavelengths; η represents the change in photovoltaic efficiency of the P-type photovoltaic cell; η represents the photovoltaic efficiency of the photovoltaic cell; η1 represents the initial photovoltaic efficiency of the photovoltaic cell; η2 represents the photovoltaic efficiency of the photovoltaic cell after gain; the correction coefficient k value of the gain of the actual photoelectric conversion efficiency of different types of coatings is obtained by calculation.

3. The method for predicting and evaluating the optical performance of photoluminescent high-transmittance photovoltaic coatings according to claim 1, characterized in that: The coating prepared by the method comprises, by mass percentage, the following components: 99.8-99.9% polymer-based resin, 1-2‰ organic photoluminescent filler or 1-2‰ inorganic photoluminescent filler.

4. The method for predicting and evaluating the optical performance of a photoluminescent high-transmittance photovoltaic coating according to claim 3, characterized in that: The photoluminescent filler is one of inorganic or organic downconversion, upconversion, plasma, or long afterglow photoluminescent materials.

5. The method for predicting and evaluating the optical performance of a photoluminescent high-transmittance photovoltaic coating according to claim 3, characterized in that: The polymer-based resin is selected from one or more of PG resin, waterborne polyurethane, waterborne acrylic, and waterborne fluorocarbon resin.

6. The method for predicting and evaluating the optical performance of photoluminescent high-transmittance photovoltaic coatings according to claim 1, characterized in that: The organic photoluminescent filler is ground at room temperature for 2-4 hours; the inorganic photoluminescent filler is ground at room temperature for 4-6 hours.

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