Method for measuring temperature coefficient of perovskite photovoltaic module

Abstract

The invention provides a method for measuring the temperature coefficient of a perovskite photovoltaic module, and the method comprises the steps: calibrating the irradiance to 1000 + / -20W / m through a steady-state solar simulator under the conditions that the environment temperature is 23.0 + / -5.0 DEG C and the humidity is less than or equal to 50% RH, fixing the module on a temperature control platform through a heat conduction pad, and monitoring the temperature through a patch type temperature sensor. Stability judgment is carried out before measurement, electrical parameters are sequentially measured from high temperature to low temperature after stability is confirmed, data are tested and recorded through an I-V curve, and temperature coefficients and relative temperature coefficients of short-circuit current (alpha), open-circuit voltage (beta) and maximum power (delta) are calculated through linear fitting of a least square method. The method solves the problems that the perovskite battery needs to be packaged to ensure the measurement stability and the assembly temperature is difficult to accurately monitor, the measurement accuracy is effectively ensured, and the temperature coefficient measurement reliability and the research and development efficiency are improved.

Description

Technical Field

[0001] This invention relates to the field of perovskite photovoltaic module measurement, and particularly to a method for measuring the temperature coefficient of perovskite photovoltaic modules. Background Technology

[0002] According to IEC standards, the temperature coefficient of a photovoltaic (PV) device typically refers to the temperature coefficients of three key power generation parameters: short-circuit current, open-circuit voltage, and maximum power. The temperature coefficient is obtained by measuring the IV characteristic curves of the PV device under different temperatures under natural or simulated sunlight, obtaining these key power generation parameters, and then linearly fitting them to the temperature. Measuring the temperature coefficient of a PV device using the simulated sunlight method requires instruments and equipment such as a solar simulator, temperature control device, temperature measurement equipment, and an IV curve testing system. Stable and uniform simulated solar irradiance, stable and uniform PV device temperature, accurate temperature measurement, and accurate electrical parameter measurement are fundamental to accurately measuring the temperature coefficient.

[0003] Current temperature coefficient measurement methods are suitable for silicon-based photovoltaic devices. Silicon-based photovoltaic devices are chemically stable and can be exposed to air for extended periods. No encapsulation protection is required during temperature coefficient measurement, making it easy to effectively control the temperature of devices only a few hundred micrometers thick. The thinness of these devices also facilitates accurate temperature measurements. Perovskite photovoltaic devices, however, require encapsulation protection because their active layer is sensitive to air composition, ensuring device stability. Encapsulated devices have low heat transfer efficiency on temperature control platforms, leading to greater difficulty in temperature control and reduced temperature uniformity in large-area devices. Furthermore, the barrier effect of the encapsulation material makes accurate temperature measurement of encapsulated devices more challenging. Differences in material properties and device structure further complicate the measurement of the temperature coefficient of perovskite photovoltaic devices.

[0004] The measurement method disclosed in Chinese invention patent CN 118783896 A uses a component sample manufactured in the same batch as the perovskite component under test as a temperature standard component, and employs a lamination process to directly contact the temperature sensor with the perovskite chip film layer of the temperature standard component. Both components are placed simultaneously on a test platform, and when measuring the electrical parameters of the perovskite component under test, the temperature of the temperature standard component is used as the temperature of the perovskite component under test. This method obtains the temperature of the perovskite module under test through an alternative approach, but it also presents several measurement challenges: (i) the consistency between module samples manufactured in the same batch cannot be determined, and differences between samples may lead to temperature measurement errors; (ii) the mechanical strength of the perovskite chip film is generally low, and the temperature sensor is in direct contact with it and requires further pressure during the lamination process, which may damage the film and affect the accuracy of temperature measurement; (iii) the perovskite module under test and the temperature standard module were not tested simultaneously using IV curves. The light irradiation absorbed by the module under test is partially converted into electrical energy output, while the temperature standard module completely absorbs the irradiation and converts it into heat, which also leads to a temperature difference between the two. Furthermore, when the temperature of the perovskite photovoltaic device is controlled without simulated solar irradiation and then subjected to simulated solar irradiation after the temperature has stabilized, the device temperature rises rapidly by at least 5°C and cannot be maintained in a stable state. The method proposed in patent CN118783896A is to turn on the solar simulator after the device temperature has stabilized, but it does not take into account the phenomenon that the device temperature rises after being subjected to simulated solar irradiation. Summary of the Invention

[0005] The purpose of this invention is to provide an efficient, convenient, and accurate method for measuring the temperature coefficient of perovskite photovoltaic modules.

[0006] This invention is implemented as follows: a method for measuring the temperature coefficient of a perovskite photovoltaic module, comprising the following steps: S1. Set environmental conditions: Temperature 23.0 ± 5.0°C; Humidity ≤ 50% RH; S2. Calibrate and debug the solar simulator; After turning on the solar simulator and warming it up, place the standard solar cell on the test platform and use the standard solar cell to calibrate the irradiance of the solar simulator on the sample surface; S3. Install the measuring equipment; specific steps include: S31. Remove the standard solar cell, attach a thermal pad to one side of the working surface of the patch temperature sensor, then attach the patch temperature sensor tightly to the back of the perovskite photovoltaic module to measure the module temperature, and fix it on the temperature control platform. S32. Adjust the height of the temperature control platform so that the light-receiving surface of the perovskite photovoltaic module is at the same height as the light-receiving surface of the standard solar cell; S33. Turn on the solar cell power testing equipment, connect the electrode leads of the perovskite photovoltaic module to the testing equipment, and connect the patch temperature sensor to the temperature monitoring equipment. S4. Set the temperature range for the electrical parameters of the perovskite photovoltaic module; the width of the temperature range is at least 30°C, and it covers a temperature point of 25°C and has at least six temperature points with equal step sizes. S5. Measure the electrical parameters of the perovskite photovoltaic module twice at the upper temperature limit. The specific operation is as follows: The time interval for irradiation by the solar simulator is set, and the shutter is opened. The temperature control platform is used to heat the perovskite photovoltaic module to the upper limit of the set measurement temperature range. At the same time, the temperature of the perovskite photovoltaic module is controlled under sunlight for at least 0.5 hours until the reading of the temperature monitoring device reaches the target temperature and the reading stabilizes. Electrical parameters are then measured. After the perovskite photovoltaic module is kept at this temperature and irradiated for the set time interval, electrical parameters are measured again. The stable reading means that the temperature is kept within ±2°C of the target temperature during the measurement process. The method for measuring the electrical parameters is as follows: Based on the characteristics of the perovskite photovoltaic module, a suitable voltage scan range and current range are set, and the perovskite photovoltaic module is subjected to continuous IV curve testing using the solar cell power testing equipment. The continuous IV curve testing refers to performing multiple IV curve tests on the perovskite photovoltaic module at the same temperature point using the solar cell power testing equipment, repeating the measurement three times, and taking the average of the three measurements as the electrical parameter I. SC V OC and P max The measured value; S6. Determine the temperature stability of the component; calculate the relative deviation between the two electrical parameter measurements in S5 and determine whether the relative deviation exceeds ±2%; if not, proceed to the next step. S7. Perform electrical parameter measurements; measure the component electrical parameters I at each temperature point from high to low temperature. SC V OC and P max Specifically, it includes: S71. Use a temperature platform to adjust the component temperature, and simultaneously control the component temperature under illumination for at least 0.5 hours until the temperature monitoring device reaches the target temperature point and the reading stabilizes. Then, measure the electrical parameters to obtain the corresponding electrical parameter values ​​I. SC V OC and P max ; S72. After the electrical parameters of the current target temperature point are measured, return to S71 to control the temperature of the next target temperature point, until the electrical parameters of all target temperature points are measured. S73, the electrical parameter value I obtained at the same temperature point SC V OC and P max As a set of data; S8. Obtain the electrical parameter value I from S7. SC V OC and P max As a function of the measured temperature, the coefficient of determination R of the least squares linear fit for each set of data is calculated. 2 The fitting slope was determined, and a plot of the data points was created for visual inspection; the coefficient of determination R was then determined. 2 Is it greater than 0.95? If yes, proceed to the next step. If no, confirm whether there is a linear relationship between the electrical parameter and the temperature. S9. The I calculated in S8 SC V OC and P max The corresponding fitting slopes are used as the short-circuit current temperature coefficient α, open-circuit voltage temperature coefficient β, and maximum power temperature coefficient δ of the perovskite photovoltaic module, respectively, and the relative temperature coefficient α is calculated. rel β rel and δ rel .

[0007] Furthermore, the irradiance in S2 is specifically: 1000 ± 20 W / m 2 .

[0008] Furthermore, the thermal conductivity of the thermal pad described in S3 is 5.0 W / mK.

[0009] Furthermore, the temperature sensor in S3 is placed in a specific manner as follows: multiple temperature points are used to locate a single perovskite photovoltaic module, and the average value of the multiple temperature points is taken as the temperature of the module.

[0010] Furthermore, the calculation steps for the relative deviation described in S6 are as follows: According to Equation 1: Calculate the relative deviation between the two short-circuit current measurements, in Equation 1: RD I To account for the relative deviation between the two short-circuit current measurements, I SC,1 I is the short-circuit current of the perovskite photovoltaic module before it undergoes a 1-hour high-temperature and irradiation test. SC,2 The short-circuit current of the perovskite photovoltaic module after undergoing a 1-hour high-temperature and irradiation test; According to Equation 2: Calculate the relative deviation between the two open-circuit current measurements, in Equation 2: RD V V represents the relative deviation between two open-circuit voltage measurements. OC,1V is the open-circuit voltage of the perovskite photovoltaic module before it undergoes a 1-hour high-temperature and irradiation test. OC,2 The open-circuit voltage of the perovskite photovoltaic module after undergoing a 1-hour high-temperature and irradiation test; According to Equation 3: Calculate the relative deviation between the two maximum power measurements, in Equation 3: RD P P represents the relative deviation between the two maximum power measurements. max,1 P represents the maximum power output of the perovskite photovoltaic module before it undergoes a 1-hour high-temperature and irradiation test, as described above. max,2 The maximum power of the perovskite photovoltaic module after undergoing a 1-hour high-temperature and irradiation test is given.

[0011] Furthermore, if the relative deviation between the two electrical parameter measurements in S6 exceeds ±2%, it indicates that the perovskite photovoltaic module has poor stability. During the measurement process, the measurement results may be inaccurate due to irreversible changes in the perovskite cells. It is necessary to lower the upper limit of the measurement temperature and re-evaluate the stability of the module. If the temperature range is reduced to within 30°C and still fails to meet the requirements, it is determined that the perovskite photovoltaic module has poor stability and is not suitable for temperature coefficient measurement.

[0012] Furthermore, in step S8, if the electrical parameters of the perovskite photovoltaic module are found to have an inflection point within the measurement temperature range according to the data point graph, then the electrical parameters need to be measured at different temperatures near the inflection point with a temperature step of no more than 1°C in order to determine the location of the inflection point.

[0013] Furthermore, the method for calculating the relative temperature coefficient in S9 is as follows: According to Equation 4: The relative temperature coefficient of the short-circuit current is calculated, in Equation 4: α rel I is the temperature coefficient of short-circuit current. SC (STC) is the short-circuit current under the standard test condition STC; According to Equation 5: The relative temperature coefficient of open-circuit voltage is calculated, in Equation 5: β rel V is the open-circuit voltage temperature coefficient; OC (STC) is the open-circuit voltage under standard test condition STC; According to Equation 6: The maximum power relative temperature coefficient is calculated, in Equation 6: δ rel P is the temperature coefficient of maximum power. max (STC) represents the maximum power under standard test conditions STC.

[0014] The beneficial effects of this invention are: 1. This invention solves the problem of uncertain consistency between module samples manufactured in the same batch and the potential for measurement temperature errors due to differences between samples by directly measuring perovskite photovoltaic modules. At the same time, it also solves the problem that perovskite cells are unstable in air and need to be packaged into perovskite photovoltaic modules to meet the requirement of maintaining high stability of the cells during temperature coefficient measurement, but it is difficult to accurately measure the module temperature.

[0015] 2. The present invention applies a thermally conductive pad between the working surface of the patch-type temperature sensor and the perovskite photovoltaic module, which improves the heat transfer effect and avoids damage to the perovskite cell film layer, thus affecting the accuracy of temperature measurement.

[0016] 3. The present invention proposes that the component continuously receives simulated solar radiation during temperature control to ensure stable and uniform temperature and accurate and reliable electrical parameter measurement results.

[0017] 4. This invention also proposes adding a thermal stability verification step when measuring the temperature coefficient of perovskite photovoltaic modules. Specifically, before measuring the module's electrical parameters at different temperatures, the module temperature is controlled at the upper limit of the measurement temperature range, and the module is subjected to simulated solar irradiation for 1 hour. The electrical parameters of the module before and after this step are measured and compared to determine its light and thermal stability within that temperature range. Verifying module stability before temperature coefficient measurement can efficiently screen modules with good stability and measurable temperature coefficients, accelerating the R&D progress of perovskite photovoltaic modules. Especially for the measurement of multiple modules, it can save time and improve R&D efficiency. Attached Figure Description

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

[0019] Figure 1 This is a schematic diagram of the framework of the temperature coefficient measurement procedure of the present invention.

[0020] Figure 2 This is a schematic diagram showing the placement of the temperature sensor of the present invention.

[0021] Figure 3 This is a table showing the IV characteristic parameters of a perovskite photovoltaic module of the present invention at different temperatures.

[0022] Figure 4 The short-circuit current I of the perovskite photovoltaic module of this invention SC A diagram illustrating the change with temperature.

[0023] Figure 5 V is the open-circuit voltage of the perovskite photovoltaic module of this invention. OC A diagram illustrating the change with temperature.

[0024] Figure 6 The maximum power P of the perovskite photovoltaic module of this inventionmax A diagram illustrating the change with temperature.

[0025] Figure 7 This is a table showing the temperature coefficient measurement results of a perovskite photovoltaic module according to the present invention. Detailed Implementation

[0026] This embodiment provides a method for measuring the temperature coefficient of perovskite photovoltaic modules, including the following steps: S1. Set environmental conditions: temperature (23.0 ± 5.0)°C; humidity ≤50% RH; during the measurement process, the ambient temperature and humidity must be controlled to remain under the above conditions to avoid degradation or performance changes of the perovskite material due to temperature and humidity fluctuations, to provide a stable basic environment for subsequent temperature coefficient measurements, and to ensure that the changes in electrical parameters of the component at different temperature points are caused only by the difference in the target temperature, rather than environmental interference. S2. Calibrate and debug the solar simulator; after turning on the solar simulator and warming it up, place a standard solar cell on the test platform and use the standard solar cell to calibrate the irradiance of the solar simulator on the sample surface to (1000 ± 20) W / m². 2 This avoids measurement errors of electrical parameters such as short-circuit current (Isc) and open-circuit voltage (Voc) caused by irradiance deviation, ensures the comparability of electrical parameter data at different temperature points, and provides accurate raw data for subsequent calculation of temperature coefficient through linear fitting. S3. Install the measuring equipment; the specific steps are as follows: S31. Remove the standard solar cell. After attaching a thermal pad to one side of the working surface of the patch-type temperature sensor, firmly attach it to the back of the perovskite photovoltaic module for measuring the module temperature, and fix it on the temperature control platform. The thermal pad used has a thermal conductivity of 5.0 W / mK, which avoids direct contact between the sensor and the perovskite film layer, and also improves the heat conduction efficiency, making the measured temperature value closer to the actual temperature of the module. The patch-type temperature sensor uses multiple temperature points for a single perovskite photovoltaic module, and the average of multiple temperature points is used as the temperature of the module, further reducing the impact of local temperature deviations. The patch-type temperature sensor can be placed as needed. Figure 2 This is just one of the placement methods.

[0027] S32. Adjust the height of the temperature control platform to make the light-receiving surface of the perovskite photovoltaic module consistent with the light-receiving surface of the standard solar cell, so as to ensure that the irradiance is uniform and stable during the measurement process, avoid uneven irradiance distribution caused by height difference, and reduce the measurement error of electrical parameters. S33. Turn on the solar cell power testing equipment, connect the electrode leads of the perovskite photovoltaic module to the testing equipment, and connect the surface-mount temperature sensor to the temperature monitoring equipment; realize the electrical parameters (I SC VOC P max The synchronous acquisition of temperature data provides accurate correlation data for subsequent temperature coefficient calculation.

[0028] S4. Set the temperature range for the electrical parameters of the perovskite photovoltaic module under test. The temperature range should be at least 30°C wide, covering a 25°C temperature point and including at least six temperature points with approximately equal step sizes. In this embodiment, the temperature range is set to 22°C to 55°C, and the step size is set to 1°C. A temperature range width of at least 30°C and including at least six equal step temperature points ensures sufficient data for subsequent least-squares linear fitting, ensuring the reliability of the linear fitting results between electrical parameters and temperature, and making the temperature coefficient calculation results credible. It is explicitly required to cover a 25°C temperature point, which is the reference temperature of the Standard Test Condition (STC), facilitating the correlation between the measurement results and electrical parameters under standard conditions, and supporting the calculation of the relative temperature coefficient. The distribution of equal step temperature points can evenly cover the temperature range. If an inflection point appears in the electrical parameters, sufficient temperature points can promptly detect nonlinear regions, providing a basis for subsequent intensified measurements (such as 1°C steps) and avoiding the omission of inflection points due to data sparsity.

[0029] S5. Measure the electrical parameters of the perovskite photovoltaic module twice at the upper temperature limit, with a time interval of 1 hour; the specific operation is as follows: Open the solar simulator shutter and use the temperature control platform to heat the perovskite photovoltaic module to the upper limit of the set measurement temperature range of 55°C. At the same time, control the temperature of the perovskite photovoltaic module under sunlight for at least 0.5 hours until the temperature monitoring device reaches the target temperature and stabilizes (keeping the temperature within ±2°C of the target temperature), and then measure the electrical parameters. After the perovskite photovoltaic module is maintained at this temperature and receives simulated solar irradiation for 1 hour, measure the electrical parameters again. The method for measuring electrical parameters is as follows: Set an appropriate voltage scan range and current range according to the perovskite photovoltaic module's specifications; use a solar cell power testing device to perform continuous IV curve tests on the perovskite photovoltaic module; record the module's electrical parameters and the temperature during measurement; and repeat the I-measurement process. SC V OC and P max The measurements were performed three times, and the average value was used as the measurement value to reduce the error of a single measurement, ensure the repeatability and accuracy of the electrical parameter data, and provide a reliable basis for subsequent stability judgment (S6); during the measurement process, the temperature was kept within ±2°C of the target temperature; by comparing the I values ​​of the two measurements... SC V OC P max This can determine whether the component has undergone irreversible degradation under high-temperature irradiation; S6. Determine the temperature stability of the component; calculate the relative deviation between the two electrical parameter measurements in S5 and determine whether the relative deviation exceeds ±2%; if not, proceed to the next step. The calculation steps are as follows: According to Equation 1: Calculate the relative deviation between the two short-circuit current measurements, in Equation 1: RD I To account for the relative deviation between the two short-circuit current measurements, I SC ,1 represents the short-circuit current of the perovskite photovoltaic module before it undergoes a 1-hour high-temperature and irradiation test, I SC ,2 is the short-circuit current of the perovskite photovoltaic module after undergoing a 1-hour high-temperature and irradiation test; According to Equation 2: Calculate the relative deviation between the two open-circuit current measurements, in Equation 2: RD V V represents the relative deviation between two open-circuit voltage measurements. OC,1 V is the open-circuit voltage of the perovskite photovoltaic module before it undergoes a 1-hour high-temperature and irradiation test. OC,2 The open-circuit voltage of the perovskite photovoltaic module after undergoing a 1-hour high-temperature and irradiation test; According to Equation 3: Calculate the relative deviation between the two maximum power measurements, in Equation 3: RD P P represents the relative deviation between the two maximum power measurements. max,1 P represents the maximum power output of the perovskite photovoltaic module before it undergoes a 1-hour high-temperature and irradiation test, as described above. max,2 The maximum power of the perovskite photovoltaic module after undergoing a 1-hour high-temperature and irradiation test is given.

[0030] If the relative deviation between the two measurement results does not exceed ±2%, it indicates that the module has good light and thermal stability and can be measured for temperature coefficient. Conversely, it indicates that the stability of the perovskite photovoltaic module under test is poor. During the measurement process, the measurement results may be inaccurate due to irreversible changes in the perovskite cells. It is necessary to lower the upper limit of the measurement temperature and re-evaluate the stability of the module. If the temperature range is narrowed down to within 30°C and still fails to meet the requirements, the perovskite photovoltaic module under test is judged to have poor stability and is not suitable for temperature coefficient measurement. Performing stability verification early in the temperature coefficient measurement process can quickly eliminate modules with poor stability. S7. Perform electrical parameter measurements; measure the module's electrical parameters sequentially from high to low temperature to avoid irreversible degradation of perovskite modules due to thermal stress during repeated temperature increases and decreases, ensuring data consistency across the entire temperature range; specifically including: S71. Use a temperature platform to adjust the component temperature, and simultaneously control the component temperature under illumination for at least 0.5 hours until the temperature monitoring device reaches the target temperature point and stabilizes. Then, measure the electrical parameters to obtain the corresponding electrical parameter values ​​I.SC V OC and P max During the measurement process, the temperature monitoring equipment is kept at the target temperature and stable, which can eliminate the instantaneous influence of dynamic temperature changes on electrical parameters and ensure that the electrical parameter data at each temperature point truly reflects the steady-state performance at that temperature. S72. After the electrical parameters of the current target temperature point are measured, return to S71 to control the temperature of the next target temperature point, until the electrical parameters of all target temperature points are measured. S73, the electrical parameter value I obtained by measuring at the same temperature point SC V OC and P max As a set of data; S8. Obtain the electrical parameter value I from S7. SC V OC and P max As a function of the measured temperature, the coefficient of determination R of the least squares linear fit for each set of data is calculated. 2 The fitting slope is calculated, and a data point plot is generated to visually examine data points or potential inflection points, providing a verification basis for inflection point densification measurements in S7 and ensuring that the data distribution conforms to the premise of linear fitting; if the coefficient of determination R... 2 A value greater than 0.95 indicates a good linear relationship between the electrical parameter and temperature, in which case the fitted slope can be used as a valid temperature coefficient, and the temperature coefficient is valid within the specified temperature range; otherwise, it is necessary to further confirm whether there is a linear relationship between the electrical parameter and temperature to avoid distortion of the temperature coefficient due to data discrepancies or nonlinearity. If the electrical parameters of the perovskite photovoltaic module under test show an inflection point within the measurement temperature range, the electrical parameters need to be measured at different temperatures near the inflection point with a temperature step of no more than 1°C to determine the location of the inflection point, avoid linear fitting distortion due to data sparsity, and ensure that the temperature range corresponds to the temperature coefficient. S9. The I calculated in S8 SC V OC and P max The corresponding fitting slopes are used as the short-circuit current temperature coefficient α, open-circuit voltage temperature coefficient β, and maximum power temperature coefficient δ of the perovskite photovoltaic module under test, respectively, and the relative temperature coefficient α is calculated. rel β rel and δ rel The calculation method is as follows: According to Equation 4: The relative temperature coefficient of the short-circuit current is calculated, in Equation 4: α rel I is the temperature coefficient of short-circuit current. SC (STC) is the short-circuit current under the standard test condition STC; According to Equation 5: The relative temperature coefficient of open-circuit voltage is calculated, in Equation 5: β rel V is the open-circuit voltage temperature coefficient; OC (STC) is the open-circuit voltage under standard test condition STC; According to Equation 6: The maximum power relative temperature coefficient is calculated, in Equation 6: δ rel P is the temperature coefficient of maximum power. max (STC) represents the maximum power under standard test conditions STC.

[0031] The electrical parameters of a perovskite photovoltaic module were measured using the above method at different temperatures, as follows: Figure 3 As shown, the relative deviations of the electrical parameters of this component before and after 1 hour of simulated solar irradiation at the upper limit temperature of 55°C were all within ±2%, indicating good light and thermal stability within the measurement temperature range. Figure 3 The data were plotted as a scatter plot, and a linear fit was performed on the data. The fitting results for short-circuit current, open-circuit voltage, and maximum power are shown below. Figure 4-6 As shown in the figure, the short-circuit current, open-circuit voltage, and maximum power of the component exhibit inflection points at approximately 30°C, 25°C, and 30°C, respectively. The temperature coefficients of each electrical parameter show significant changes before and after these inflection points. The linear fitting determination coefficients R0 for each electrical parameter are... 2 All values ​​are greater than 0.95, indicating high linearity. The temperature coefficients of each electrical parameter calculated based on the linear fitting results are... Figure 7 As shown.

[0032] The measurement method provided by this invention has the following advantages: 1. It can be directly used to measure perovskite photovoltaic modules, solving the problem that the consistency between module samples made in the same batch cannot be determined and the differences between samples may lead to measurement temperature errors. At the same time, it also solves the problem that perovskite cells are unstable in air and need to be encapsulated into perovskite photovoltaic modules to meet the requirement of maintaining high stability of the cells during temperature coefficient measurement, but it is difficult to accurately measure the module temperature.

[0033] 2. The present invention applies a thermally conductive pad between the working surface of the patch-type temperature sensor and the perovskite photovoltaic module, which improves the heat transfer effect and avoids damage to the perovskite cell film layer, thus affecting the accuracy of temperature measurement.

[0034] 3. The present invention proposes that the component continuously receives simulated solar radiation during temperature control to ensure stable and uniform temperature and accurate and reliable electrical parameter measurement results.

[0035] 4. This invention also proposes adding a thermal stability verification step when measuring the temperature coefficient of perovskite photovoltaic modules. Specifically, before measuring the module's electrical parameters at different temperatures, the module temperature is controlled at the upper limit of the measurement temperature range, and the module is subjected to simulated solar irradiation for 1 hour. The electrical parameters of the module before and after this step are measured and compared to determine its light and thermal stability within that temperature range. Verifying module stability before temperature coefficient measurement can efficiently screen modules with good stability and measurable temperature coefficients, accelerating the R&D progress of perovskite photovoltaic modules. Especially for the measurement of multiple modules, it can save time and improve R&D efficiency.

[0036] While specific embodiments of the present invention have been described above, those skilled in the art should understand that the specific embodiments described are merely illustrative and not intended to limit the scope of the present invention. Equivalent modifications and variations made by those skilled in the art in accordance with the spirit of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A method for measuring the temperature coefficient of a perovskite photovoltaic module, characterized in that: Includes the following steps: S1. Set environmental conditions: Temperature 23.0 ± 5.0°C; Humidity ≤ 50% RH; S2. Calibrate and debug the solar simulator; After turning on the solar simulator and warming it up, place the standard solar cell on the test platform and use the standard solar cell to calibrate the irradiance of the solar simulator on the sample surface; S3. Install measuring equipment; The specific steps include: S31. Remove the standard solar cell, attach a thermal pad to one side of the working surface of the patch temperature sensor, then attach the patch temperature sensor tightly to the back of the perovskite photovoltaic module to measure the module temperature, and fix it on the temperature control platform. S32. Adjust the height of the temperature control platform so that the light-receiving surface of the perovskite photovoltaic module is at the same height as the light-receiving surface of the standard solar cell; S33. Turn on the solar cell power testing equipment, connect the electrode leads of the perovskite photovoltaic module to the testing equipment, and connect the patch temperature sensor to the temperature monitoring equipment. S4. Set the temperature range for the electrical parameters of the perovskite photovoltaic module; the width of the temperature range is at least 30°C, and it covers a temperature point of 25°C and has at least six temperature points with equal step sizes. S5. Measure the electrical parameters of the perovskite photovoltaic module twice at the upper temperature limit. The specific operation is as follows: The time interval for irradiation by the solar simulator is set, and the shutter is opened. The temperature control platform is used to heat the perovskite photovoltaic module to the upper limit of the set measurement temperature range. At the same time, the temperature of the perovskite photovoltaic module is controlled under sunlight for at least 0.5 hours until the reading of the temperature monitoring device reaches the target temperature and the reading stabilizes. Electrical parameters are then measured. After the perovskite photovoltaic module is kept at this temperature and irradiated for the set time interval, electrical parameters are measured again. The stable reading means that the temperature is kept within ±2°C of the target temperature during the measurement process. The method for measuring the electrical parameters is as follows: Based on the characteristics of the perovskite photovoltaic module, a suitable voltage scan range and current range are set, and the perovskite photovoltaic module is subjected to continuous IV curve testing using the solar cell power testing equipment. The continuous IV curve testing refers to performing multiple IV curve tests on the perovskite photovoltaic module at the same temperature point using the solar cell power testing equipment, repeating the measurement three times, and taking the average of the three measurements as the electrical parameter I. SC V OC and P max The measured value; S6. Determine the temperature stability of the component; calculate the relative deviation between the two electrical parameter measurements in S5 and determine whether the relative deviation exceeds ±2%; if not, proceed to the next step. S7. Perform electrical parameter measurements; measure the component electrical parameters I at each temperature point from high to low temperature. SC V OC and P max Specifically, it includes: S71. Use a temperature platform to adjust the component temperature, and simultaneously control the component temperature under illumination for at least 0.5 hours until the temperature monitoring device reaches the target temperature point and the reading stabilizes. Then, measure the electrical parameters to obtain the corresponding electrical parameter values ​​I. SC V OC and P max ; S72. After the electrical parameters of the current target temperature point are measured, return to S71 to control the temperature of the next target temperature point, until the electrical parameters of all target temperature points are measured. S73, the electrical parameter value I obtained at the same temperature point SC V OC and P max As a set of data; S8. Obtain the electrical parameter value I from S7. SC V OC and P max As a function of the measured temperature, the coefficient of determination R of the least squares linear fit for each set of data is calculated. 2 The fitting slope was determined, and a plot of the data points was created for visual inspection; the coefficient of determination R was then determined. 2 Is it greater than 0.95? If yes, proceed to the next step. If no, confirm whether there is a linear relationship between the electrical parameter and the temperature. S9. The I calculated in S8 SC V OC and P max The corresponding fitting slopes are used as the short-circuit current temperature coefficient α, open-circuit voltage temperature coefficient β, and maximum power temperature coefficient δ of the perovskite photovoltaic module, respectively, and the relative temperature coefficient α is calculated. rel β rel and δ rel .

2. The method for measuring the temperature coefficient of a perovskite photovoltaic module according to claim 1, characterized in that: The specific irradiance in S2 is: 1000 ± 20 W / m 2 .

3. The method for measuring the temperature coefficient of a perovskite photovoltaic module according to claim 1, characterized in that: The thermal conductivity of the thermal pad described in S3 is 5.0 W / mK.

4. The method for measuring the temperature coefficient of a perovskite photovoltaic module according to claim 1, characterized in that: The temperature sensor in S3 is placed in a manner that uses multiple temperature points for a single perovskite photovoltaic module, and the average value of the multiple temperature points is used as the temperature of the module.

5. The method for measuring the temperature coefficient of a perovskite photovoltaic module according to claim 1, characterized in that: The specific steps for calculating the relative deviation described in S6 are as follows: According to Equation 1: Calculate the relative deviation between the two short-circuit current measurements, in Equation 1: RD I To account for the relative deviation between the two short-circuit current measurements, I SC,1 I is the short-circuit current of the perovskite photovoltaic module before it undergoes a 1-hour high-temperature and irradiation test. SC,2 The short-circuit current of the perovskite photovoltaic module after undergoing a 1-hour high-temperature and irradiation test; According to Equation 2: Calculate the relative deviation between the two open-circuit current measurements, in Equation 2: RD V V represents the relative deviation between two open-circuit voltage measurements. OC,1 V is the open-circuit voltage of the perovskite photovoltaic module before it undergoes a 1-hour high-temperature and irradiation test. OC,2 The open-circuit voltage of the perovskite photovoltaic module after undergoing a 1-hour high-temperature and irradiation test; According to Equation 3: Calculate the relative deviation between the two maximum power measurements, in Equation 3: RD P P represents the relative deviation between the two maximum power measurements. max,1 P represents the maximum power output of the perovskite photovoltaic module before it undergoes a 1-hour high-temperature and irradiation test, as described above. max,2 The maximum power of the perovskite photovoltaic module after undergoing a 1-hour high-temperature and irradiation test is given.

6. The method for measuring the temperature coefficient of a perovskite photovoltaic module according to claim 1, characterized in that: If the relative deviation between the two electrical parameter measurements in S6 exceeds ±2%, the upper limit of the measurement temperature needs to be lowered and the stability of the module needs to be reassessed. If the temperature range is reduced to within 30°C and still fails to meet the requirements, the perovskite photovoltaic module is deemed to have poor stability and is not suitable for temperature coefficient measurement.

7. The method for measuring the temperature coefficient of a perovskite photovoltaic module according to claim 1, characterized in that: In step S8, if the electrical parameters of the perovskite photovoltaic module are found to have an inflection point within the measurement temperature range according to the data point graph, then the electrical parameters need to be measured at different temperatures near the inflection point with a temperature step of no more than 1°C in order to determine the location of the inflection point.

8. The method for measuring the temperature coefficient of a perovskite photovoltaic module according to claim 1, characterized in that: The method for calculating the relative temperature coefficient in S9 is as follows: According to Equation 4: The relative temperature coefficient of the short-circuit current is calculated, in Equation 4: α rel I is the temperature coefficient of short-circuit current. SC (STC) is the short-circuit current under the standard test condition STC; According to Equation 5: The relative temperature coefficient of open-circuit voltage is calculated, in Equation 5: β rel V is the open-circuit voltage temperature coefficient; OC (STC) is the open-circuit voltage under standard test condition STC; According to Equation 6: The maximum power relative temperature coefficient is calculated, in Equation 6: δ rel P is the temperature coefficient of maximum power. max (STC) represents the maximum power under standard test conditions STC.

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