Solar cell detection method and solar cell detection system

Abstract

The invention relates to a solar cell detection method and a solar cell detection system. The method comprises the following steps: in response to an electroluminescence test instruction, obtaining a first photoluminescence spectrum of a to-be-tested sub-cell; first exciting light is applied to the laminated cell, at least the to-be-tested sub-cell and the associated sub-cell are excited to be in a light-emitting state, and the associated sub-cell and the to-be-tested sub-cell are sequentially and adjacently arranged in the sub-cell current transmission direction corresponding to the test electric signal; applying a first test electric signal to the laminated cell to obtain a test emergent light spectrum of the to-be-tested sub-cell; and determining the electroluminescence spectrum of the to-be-tested sub-cell according to the first photoluminescence spectrum of the to-be-tested sub-cell and the test emergent light spectrum. The laminated cell can be subjected to an electroluminescence test and a photoluminescence test, and the accuracy of the electroluminescence test of the laminated cell is effectively improved.

Description

Technical Field

[0001] The present application relates to the technical field of photovoltaic detection, and in particular to a method for detecting a solar cell and a solar cell detection system. Background Art

[0002] In recent years, with the continuous consumption of traditional energy, people's awareness of environmental protection has been continuously improved. As a clean energy source, solar energy has attracted much attention for directly converting light radiation into electrical energy through solar cells.

[0003] Solar cells mainly utilize the unique conduction and valence band structures of semiconductors. Through the drift and diffusion of carriers between PN junctions, photo-generated electrons and holes can be separated and a current loop can be formed through an external circuit. Thus, according to the requirements for voltage and current, solar cells that meet the requirements can be obtained by connecting multiple sub-cells in series and parallel.

[0004] Currently, tandem cells are formed by vertically stacking multiple sub-cells of different materials, which can simultaneously utilize optical signals of different wavelengths, thereby efficiently utilizing solar energy. However, traditional electroluminescence tests and traditional photoluminescence tests for solar cells are difficult to meet the test requirements of tandem cells. Summary of the Invention

[0005] Based on this, the embodiments of the present application provide a method for detecting a solar cell and a solar cell detection system, which can perform electroluminescence tests and photoluminescence tests on tandem cells and effectively improve the accuracy of electroluminescence tests for tandem cells.

[0006] To achieve the above object, on the one hand, some embodiments of the present application provide a method for detecting a solar cell, which is applied to a tandem cell. The tandem cell includes at least two sub-cells stacked in sequence. The method for detecting a solar cell includes the following steps.

[0007] In response to an electroluminescence test instruction, obtain a first photoluminescence spectrum of the sub-cell to be tested.

[0008] Apply a first excitation light to the tandem cell to excite at least the sub-cell to be tested and the associated sub-cell into a light-emitting state. Among them, the associated sub-cell is adjacent to the sub-cell to be tested in sequence along the sub-cell current transmission direction corresponding to the test electrical signal.

[0009] Apply a first test electrical signal to the tandem cell to obtain a test emission spectrum of the sub-cell to be tested.

[0010] Determine the electroluminescence spectrum of the sub-cell to be tested according to the first photoluminescence spectrum and the test emission spectrum of the sub-cell to be tested.

[0011] In some embodiments of the present application, the associated sub-cell is located on the side of the sub-cell to be measured where the positive electrode for connecting the test power supply is located; the number of associated sub-cells is one or more.

[0012] In some embodiments of the present application, applying the first excitation light to the stacked cell to at least excite the sub-cell to be measured and the associated sub-cell into a light-emitting state includes: applying the first excitation light to the stacked cell to excite each sub-cell of the stacked cell into a light-emitting state.

[0013] In some embodiments of the present application, the wavelength of the first excitation light is within the excitation spectral range of the sub-cell to be measured, and the wavelength of the first excitation light is greater than the excitation light wavelength of the associated sub-cell.

[0014] In some embodiments of the present application, the first test electrical signal includes a test voltage and / or a test current.

[0015] Optionally, the value range of the test voltage includes: 0.1% to 200% of the open-circuit voltage of the stacked cell.

[0016] Optionally, the value range of the test voltage includes: 0.1% to 120% of the open-circuit voltage of the stacked cell.

[0017] Optionally, the value range of the test voltage includes: 0.1% to 100% of the open-circuit voltage of the stacked cell.

[0018] Optionally, the value range of the test voltage includes: 5% to 30% of the open-circuit voltage of the stacked cell.

[0019] Optionally, the value range of the test current includes: 0.1% to 200% of the short-circuit current of the stacked cell.

[0020] Optionally, the value range of the test current includes: 0.1% to 120% of the short-circuit current of the stacked cell.

[0021] Optionally, the value range of the test current includes: 0.1% to 100% of the short-circuit current of the stacked cell.

[0022] Optionally, the value range of the test current includes: 5% to 30% of the short-circuit current of the stacked cell.

[0023] In some embodiments of the present application, obtaining the first photoluminescence spectrum and the test output light spectrum of the sub-cell to be measured includes: setting a target filter on the light incident side of the spectral acquisition device, where the target filter corresponds to the sub-cell to be measured one by one, and the target filter is configured to select the output light signal passing through the sub-cell to be measured; obtaining the first photoluminescence spectrum and the test output light spectrum of the sub-cell to be measured based on the target filter respectively.

[0024] In some embodiments of the present application, the solar cell detection method further includes: in response to a photoluminescence test instruction, applying a second excitation light to the tandem cell; and based on a target filter, obtaining a second photoluminescence spectrum of the sub-cell to be tested for photoluminescence testing.

[0025] In some embodiments of the present application, the wavelength of the second excitation light is the same as the wavelength of the first excitation light. Correspondingly, the step of obtaining the first photoluminescence spectrum of the sub-cell to be tested in response to an electroluminescence test instruction includes: in response to the electroluminescence test instruction, using the second photoluminescence spectrum as the first photoluminescence spectrum.

[0026] In some embodiments of the present application, the step of determining the electroluminescence spectrum of the sub-cell to be tested according to the first photoluminescence spectrum and the measured light output spectrum of the sub-cell to be tested includes: obtaining the light emission data of the sub-cell to be tested in the first photoluminescence spectrum as first data; obtaining the light emission data of the sub-cell to be tested in the measured light output spectrum as second data; and determining the electroluminescence spectrum of the sub-cell to be tested according to the data difference between the second data and the first data.

[0027] In some embodiments of the present application, the tandem cell includes a first end for connecting to the positive electrode of a test power supply and a second end for connecting to the negative electrode of the test power supply. The aforementioned sub-cell to be tested is the Nth sub-cell connected to the first end of the tandem cell, where N is a positive integer greater than or equal to 2. Correspondingly, the solar cell detection method further includes: applying a second test electrical signal to the first end and the second end of the tandem cell; and directly obtaining the electroluminescence spectrum of the first sub-cell connected to the first end.

[0028] In some embodiments of the present application, the tandem cell includes a perovskite sub-cell and a crystalline silicon sub-cell; wherein, the crystalline silicon sub-cell is located on the side of the perovskite sub-cell for connecting to the positive electrode of the test power supply.

[0029] In some embodiments of the present application, the tandem cell includes a first bandgap sub-cell and a second bandgap sub-cell; wherein, the bandgap of the first bandgap sub-cell is less than the bandgap of the second bandgap sub-cell, and the first bandgap sub-cell is located on the side of the second bandgap sub-cell for connecting to the positive electrode of the test power supply.

[0030] Optionally, the bandgap range of the first bandgap sub-cell includes 1.0 eV to 1.2 eV. The bandgap range of the second bandgap sub-cell includes 1.6 eV to 1.8 eV.

[0031] Optionally, the bandgap range of the sub-cell to be tested includes 1.6 eV to 1.8 eV. The wavelength range of the first excitation light includes 300 nm to 650 nm.

[0032] On the other hand, some embodiments of the present application further provide a solar cell detection system, which is applied to a stacked cell. The stacked cell includes at least two sub-cells stacked in sequence. This solar cell detection system is used to implement the solar cell detection method described in the above-mentioned some embodiments, and includes: a controllable light source, a spectral acquisition device, and a detection and processing device.

[0033] The controllable light source is configured to: emit a first excitation light to the stacked cell in response to an electroluminescence test instruction, and the first excitation light is used to at least excite the sub-cell to be tested and the associated sub-cell to be in a light-emitting state; wherein, the associated sub-cell and the sub-cell to be tested are arranged adjacent to each other in sequence along the sub-cell current transmission direction corresponding to the test electrical signal.

[0034] The spectral acquisition device is configured to: acquire the first photoluminescence spectrum of the sub-cell to be tested in response to an electroluminescence test instruction, and acquire the test outgoing light spectrum of the sub-cell to be tested in response to a first test electrical signal.

[0035] The detection and processing device is connected to the controllable light source and the spectral acquisition device, and is configured to: send an electroluminescence test instruction to the controllable light source; apply a first test electrical signal to the stacked cell in response to the sub-cell to be tested and the associated sub-cell being in a light-emitting state; and determine the electroluminescence spectrum of the sub-cell to be tested according to the first photoluminescence spectrum and the test outgoing light spectrum of the sub-cell to be tested.

[0036] In some embodiments of the present application, the controllable light source is further configured to: emit a first excitation light that can excite each sub-cell to be in a light-emitting state to the stacked cell in response to an electroluminescence test instruction.

[0037] In some embodiments of the present application, a filter placement portion is provided on the light incident side of the spectral acquisition device; wherein, the filter placement portion is used to place a target filter. The target filter corresponds to the sub-cell to be tested one by one, and is configured to select the outgoing light signal passing through the sub-cell to be tested. Correspondingly, the spectral acquisition device is configured to: acquire the first photoluminescence spectrum and the test outgoing light spectrum of the sub-cell to be tested based on the target filter respectively.

[0038] In some embodiments of the present application, the detection and processing device is further configured to: send a photoluminescence test instruction to the controllable light source. The controllable light source is further configured to: emit a second excitation light to the stacked cell in response to the photoluminescence test instruction. The spectral acquisition device is further configured to: acquire the second photoluminescence spectrum of the sub-cell to be tested in response to the photoluminescence test instruction.

[0039] Optionally, the wavelength of the second excitation light is the same as the wavelength of the first excitation light. Correspondingly, the spectral acquisition device acquires the first photoluminescence spectrum of the sub-cell to be tested in response to an electroluminescence test instruction, including: in response to the electroluminescence test instruction, taking the second photoluminescence spectrum as the first photoluminescence spectrum.

[0040] In some embodiments of the present application, the stacked cell includes a first end for connecting to the positive electrode of a test power source and a second end for connecting to the negative electrode of the test power source. The sub-cell to be measured is the Nth sub-cell connected to the first end, where N is a positive integer greater than or equal to 2. Correspondingly, the detection processing device is further configured to: apply a second test electrical signal to the first end and the second end of the stacked cell, so that the spectral acquisition device directly obtains the electroluminescence spectrum of the first sub-cell connected to the first end in response to the second test electrical signal.

[0041] The embodiments of the present application may / at least have the following advantages:

[0042] In the embodiments of the present application, when performing electroluminescence testing on a stacked cell, the sub-cell to be measured and the associated sub-cells can be excited to a light-emitting state by applying a first excitation light to the stacked cell. In this way, the sub-cell to be measured and the associated sub-cells are both in a conducting state, and a power supply path of an equivalent current source can be formed between the sub-cell to be measured and the associated sub-cells, so that it is not necessary to reverse-breakdown the equivalent recombination junction between the sub-cell to be measured and the associated sub-cells. Then, on the basis that the sub-cell to be measured and the associated sub-cells remain in the light-emitting state, by applying a first test electrical signal to the stacked cell to obtain the test emission spectrum of the sub-cell to be measured, the electroluminescence spectrum of the sub-cell to be measured can be determined by data processing based on the test emission spectrum of the sub-cell to be measured and its first photoluminescence spectrum. Thus, the embodiments of the present application can perform electroluminescence testing on the stacked cell, and effectively avoid the equivalent recombination junction between the sub-cell to be measured and the associated sub-cells from being reverse-broken down during the electroluminescence testing, thereby avoiding damage to the performance of the stacked cell caused by the breakdown of the equivalent recombination junction. Moreover, compared with the traditional electroluminescence testing, in the embodiments of the present application, the electroluminescence spectrum of the sub-cell to be measured is obtained by data processing, which can also avoid the problems of misjudging the battery performance and the distribution of thin film morphological defects caused by directly identifying the electroluminescence image of the solar cell, thereby effectively improving the accuracy of the electroluminescence testing of the stacked cell.

[0043] Details of one or more embodiments of the present application are set forth in the following drawings and description. Other features, objects, and advantages of the present application will become apparent from the specification, drawings, and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0045] Figure 1Schematic flow chart of a solar cell detection method provided in some embodiments;

[0046] Figure 2 Schematic flow chart of another solar cell detection method provided in some embodiments;

[0047] Figure 3 Schematic flow chart of a process for obtaining a first photoluminescence spectrum and measuring an emission spectrum in some embodiments;

[0048] Figure 4 Schematic flow chart of yet another solar cell detection method provided in some embodiments;

[0049] Figure 5 Schematic flow chart of yet another solar cell detection method provided in some embodiments;

[0050] Figure 6 Schematic flow chart of yet another solar cell detection method provided in some embodiments;

[0051] Figure 7 Schematic flow chart of yet another solar cell detection method provided in some embodiments;

[0052] Figure 8 Schematic structural diagram of a tandem cell provided in some embodiments;

[0053] Figure 9 For Figure 8 A layer structure diagram of the tandem cell shown;

[0054] Figure 10 For Figure 8 An equivalent circuit schematic diagram of the tandem cell shown;

[0055] Figure 11 For Figure 8 An equivalent circuit schematic diagram of the tandem cell shown after excitation luminescence;

[0056] Figure 12 Schematic structural diagram of another tandem cell provided in some embodiments;

[0057] Figure 13 Schematic block diagram of a solar cell detection system provided in some embodiments.

[0058] Description of reference numerals:

[0059] 100 - crystalline silicon sub - cell, 110 - crystalline silicon absorption layer, 120 - first passivation contact layer, 130 - second passivation contact layer, 140 - transparent conductive layer, 200 - intermediate recombination layer, 300 - perovskite sub - cell, 310 - perovskite absorption layer, 320 - hole transport layer, 330 - third passivation contact layer, 340 - electron transport layer, 350 - buffer layer, 360 - conductive oxide layer, 370 - antireflection layer, 400 - first electrode, 500 - second electrode;

[0060] 10 - controllable light source, 20 - spectral acquisition device, 30 - detection and processing device. Detailed implementation manners

[0061] For ease of understanding of this application, the following will describe this application more comprehensively with reference to the relevant drawings. Preferred embodiments of this application are shown in the drawings. However, this application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the disclosure of this application more thorough and comprehensive.

[0062] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this application belongs. The terms used in the description of this application herein are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0063] It should be understood that when an element or layer is referred to as "on", "adjacent to", or "connected to" another element or layer, it can be directly on, adjacent to, connected, or coupled to the other element or layer, or there may be intervening elements or layers. It should be understood that although the terms first, second, third, etc. may be used to describe various elements, components, regions, layers, doping types, and / or parts, these elements, components, regions, layers, doping types, and / or parts should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer, doping type, or part from another element, component, region, layer, doping type, or part. Thus, without departing from the teachings of this application, the first element, component, region, layer, doping type, or part discussed below may be referred to as the second element, component, region, layer, or part.

[0064] As used herein, the singular forms "a", "an" and "the" may also include the plural forms unless the context clearly dictates otherwise. It should also be understood that when the terms "comprising" and / or "including" are used in this specification, the presence of the stated features, integers, steps, operations, elements and / or components can be determined, but one or more other features, integers, steps, operations, elements, components and / or groups are not excluded from being present or added. Also, as used herein, the term "and / or" includes any and all combinations of the related listed items.

[0065] With the rapid development of the photovoltaic industry, the quality control and detection technologies of solar cells are also constantly advancing. Among them, photoluminescence testing and electroluminescence testing are two important detection methods for solar cells. Photoluminescence (PL for short) testing means: using excitation light with a specific wavelength to excite a solar cell, causing electrons inside it to jump to the excited state and emit light signals; thus, by capturing the light signals with a camera, the defects in the solar cell can be inferred based on the light intensity distribution of the light signals, and these defects usually appear as regions with weakened fluorescence intensity. Common photoluminescence testing defects include: impurities, cracks or changes in crystal structure. Electroluminescence (EL for short) testing means: applying a specific voltage to make the solar cell emit light in the working state; thus, by taking a luminescence image of the solar cell with an infrared camera, the internal problems of the solar cell can be visually displayed, such as defects like hidden cracks, broken grids and cracks.

[0066] The tandem cell is formed by vertically stacking multiple sub-cells of different materials, and can simultaneously utilize light signals of different wavelengths, thereby efficiently utilizing solar energy. That is, the tandem cell may include: at least two sub-cells stacked in sequence in the vertical direction. The embodiments of the present application provide a method for detecting a solar cell and a solar cell detection system, which can perform electroluminescence testing and photoluminescence testing on the tandem cell, and effectively improve the accuracy of the electroluminescence testing of the tandem cell.

[0067] Please refer to Figure 1 , the method for detecting a solar cell provided by the embodiments of the present application includes the following steps S100 to S400.

[0068] S100, in response to an electroluminescence testing instruction, obtain a first photoluminescence spectrum of the sub-cell to be tested.

[0069] Optionally, the first photoluminescence spectrum of the sub-cell to be tested can be obtained by directly performing photoluminescence testing on the sub-cell to be tested in response to the electroluminescence testing instruction.

[0070] Optionally, the first photoluminescence spectrum of the sub-cell to be measured can be obtained from the historical detection record of the photoluminescence spectrum of the sub-cell to be measured in response to the electroluminescence test instruction.

[0071] S200, Apply a first excitation light to the stacked cell to excite at least the sub-cell to be measured and the associated sub-cell into a luminous state. Among them, the associated sub-cell and the sub-cell to be measured are arranged adjacent to each other in the sub-cell current transmission direction corresponding to the test electrical signal in sequence.

[0072] Here, the test electrical signal can be provided based on a test power supply and can include the first test electrical signal and the second test electrical signal described later.

[0073] It can be understood that the sub-cell current transmission direction is from the positive electrode to the negative electrode, and the associated sub-cell is located on the side of the sub-cell to be measured for connecting the positive electrode of the test power supply. Optionally, the number of associated sub-cells can be one or more.

[0074] Optionally, the wavelength of the first excitation light is within the excitation spectrum range of the sub-cell to be measured, and the wavelength of the first excitation light is greater than the excitation light wavelength of the associated sub-cell.

[0075] Optionally, the first photoluminescence spectrum of the sub-cell to be measured obtained in step S100 can also be obtained after exciting the sub-cell to be measured and the associated sub-cell to emit light with the first excitation light and before applying the first test electrical signal.

[0076] S300, Apply a first test electrical signal to the stacked cell to obtain the test emission spectrum of the sub-cell to be measured.

[0077] Optionally, the first test electrical signal includes a test voltage and / or a test current. Among them, when the first test electrical signal includes a test voltage and a test current, the corresponding test emission spectra can be obtained for the test voltage and the test current respectively to comprehensively evaluate the electroluminescence performance of the sub-cell to be measured.

[0078] S400, Determine the electroluminescence spectrum of the sub-cell to be measured according to the first photoluminescence spectrum and the test emission spectrum of the sub-cell to be measured.

[0079] In the embodiments of the present application, when performing electroluminescence testing on a tandem cell, the sub-cell under test and the associated sub-cell can be excited to a light-emitting state by applying a first excitation light to the tandem cell. In this way, both the sub-cell under test and the associated sub-cell are in a conducting state, and a power supply path of an equivalent current source can be formed between the sub-cell under test and the associated sub-cell, so that it is not necessary to reverse-breakdown the equivalent recombination junction between the sub-cell under test and the associated sub-cell. Then, on the basis that the sub-cell under test and the associated sub-cell remain in the light-emitting state, a test emission spectrum of the sub-cell under test is obtained by applying a first test electrical signal to the tandem cell, and the electroluminescence spectrum of the sub-cell under test can be determined by means of data processing based on the test emission spectrum of the sub-cell under test and its first photoluminescence spectrum. Thus, the embodiments of the present application can perform electroluminescence testing on a tandem cell, and effectively avoid the equivalent recombination junction between the sub-cell under test and the associated sub-cell from being reverse-breakdown during the electroluminescence testing, thereby avoiding damage to the performance of the tandem cell caused by the breakdown of the equivalent recombination junction. Moreover, compared with the traditional electroluminescence testing, in the embodiments of the present application, the electroluminescence spectrum of the sub-cell under test is obtained by means of data processing, which can also avoid the problems of misjudging the battery performance and misjudging the distribution of thin-film morphological defects caused by directly identifying the electroluminescence image of the solar cell, thereby effectively improving the accuracy of the electroluminescence testing of the tandem cell.

[0080] In some embodiments of the present application, please refer to Figure 2 , in step S200, applying a first excitation light to the tandem cell to at least excite the sub-cell under test and the associated sub-cell to a light-emitting state can be represented as step S200'.

[0081] S200', applying a first excitation light to the tandem cell to excite each sub-cell of the tandem cell to a light-emitting state.

[0082] In the embodiments of the present application, when performing electroluminescence testing on a tandem cell, by using a first excitation light to excite each sub-cell in the tandem cell to a light-emitting state, the steps of specifically selecting and implementing the first excitation light can be simplified, thereby reducing the testing difficulty of the electroluminescence testing, which is conducive to ensuring the testing efficiency of the electroluminescence testing.

[0083] It should be added that, in some embodiments of the present application, the first test electrical signal includes a test voltage.

[0084] Optionally, the value range of the test voltage includes: 0.1% to 200% of the open-circuit voltage of the tandem cell; for example, it can be 0.1%, 1%, 5%, 10%, 25%, 50%, 100%, 150% or 200% of the open-circuit voltage of the tandem cell.

[0085] Optionally, the value range of the test voltage includes: 0.1% to 120% of the open-circuit voltage of the stacked cell; for example, it can be 0.1%, 3%, 8%, 12%, 20%, 40%, 60%, 90% or 120% of the open-circuit voltage of the stacked cell.

[0086] Optionally, the value range of the test voltage includes: 0.1% to 100% of the open-circuit voltage of the stacked cell; for example, it can be 0.1%, 2%, 6%, 15%, 35%, 70%, 80% or 100% of the open-circuit voltage of the stacked cell.

[0087] Optionally, the value range of the test voltage includes: 5% to 30% of the open-circuit voltage of the stacked cell; for example, it can be 5%, 7%, 9%, 16%, 21%, 28% or 30% of the open-circuit voltage of the stacked cell.

[0088] In the embodiments of the present application, when performing electroluminescence testing on the stacked cell, it is not necessary to reverse-breakdown the equivalent recombination junction between the sub-cell to be tested and the associated sub-cell, which is beneficial to performing electroluminescence testing with a smaller test voltage to avoid damaging the performance of the stacked cell due to an excessive test voltage to the greatest extent.

[0089] In some other embodiments of the present application, the first test electrical signal includes a test current.

[0090] Optionally, the value range of the test current includes: 0.1% to 200% of the short-circuit current of the stacked cell; for example, it can be 0.1%, 1%, 5%, 10%, 25%, 50%, 100%, 150% or 200% of the short-circuit current of the stacked cell.

[0091] Optionally, the value range of the test current includes: 0.1% to 120% of the short-circuit current of the stacked cell; for example, it can be 0.1%, 3%, 8%, 12%, 20%, 40%, 60%, 90% or 120% of the short-circuit current of the stacked cell.

[0092] Optionally, the value range of the test current includes: 0.1% to 100% of the short-circuit current of the stacked cell; for example, it can be 0.1%, 2%, 6%, 15%, 35%, 70%, 80% or 100% of the short-circuit current of the stacked cell.

[0093] Optionally, the value range of the test current includes: 5% to 30% of the short-circuit current of the stacked cell; for example, it can be 5%, 7%, 9%, 16%, 21%, 28% or 30% of the short-circuit current of the stacked cell.

[0094] In the embodiments of the present application, when performing electroluminescence testing on a stacked cell, it is not necessary to reversely break down the equivalent recombination junction between the sub-cell to be tested and the associated sub-cell, which is conducive to performing electroluminescence testing with a relatively small test current, so as to avoid damaging the performance of the stacked cell due to an excessive test current to the greatest extent.

[0095] In some embodiments of the present application, please refer to Figure 3 , obtaining the first photoluminescence spectrum of the sub-cell to be tested in step S100 and obtaining the test outgoing light spectrum of the sub-cell to be tested in step S300 can be represented as the following steps S110 and S120.

[0096] S110, set a target filter on the light incident side of the spectral acquisition device, where the target filter corresponds to the sub-cell to be tested one by one, and the target filter is configured to select the outgoing light signal passing through the sub-cell to be tested.

[0097] S120, respectively obtain the first photoluminescence spectrum and the test outgoing light spectrum of the sub-cell to be tested based on the target filter.

[0098] In the embodiments of the present application, by matching the outgoing light wavelength of the sub-cell to be tested to select the target filter, the outgoing light signal passing through the sub-cell to be tested can be selected by the target filter, that is: when the sub-cell to be tested and other sub-cells (such as associated sub-cells) are both emitting light, the outgoing light of the two can be noise-filtered, so as to obtain only the outgoing light signal of the sub-cell to be tested. In this way, the embodiments of the present application can accurately obtain the first photoluminescence spectrum and the test outgoing light spectrum of the sub-cell to be tested based on the target filter.

[0099] It is worth mentioning that in some embodiments of the present application, please refer to Figure 4 , the solar cell detection method further includes the following steps S500 and S600.

[0100] S500, in response to the photoluminescence test instruction, apply a second excitation light to the stacked cell.

[0101] S600, based on the target filter, obtain the second photoluminescence spectrum of the sub-cell to be tested for photoluminescence testing.

[0102] In the embodiments of the present application, by matching the different light-emitting characteristics of different sub-cells in the stacked cell, a suitable target filter can be selected to perform photoluminescence testing on different sub-cells, so as to independently obtain the second photoluminescence spectrum of each sub-cell, thereby realizing the photoluminescence testing of the stacked cell.

[0103] Optionally, the photoluminescence testing of the stacked cell and the electroluminescence testing of the stacked cell can be performed independently, or executed in a preset order. For example Figure 4As shown, the electroluminescence test of the tandem cell can be performed first, and then the photoluminescence test of the tandem cell can be performed. Alternatively, for example Figure 5 As shown, the photoluminescence test of the tandem cell can be performed first, and then the electroluminescence test of the tandem cell can be performed.

[0104] In addition, it can be understood that the second excitation light applied to the tandem cell should be set to match the photoluminescence test requirements of the tandem cell. For example, it can be the same as or different from the first excitation light.

[0105] Optionally, the wavelength of the second excitation light is the same as the wavelength of the first excitation light. Accordingly, please refer to Figure 5 , in step S100, in response to the electroluminescence test instruction, obtaining the first photoluminescence spectrum of the sub-cell to be tested can be represented as step S100'.

[0106] S100', in response to the electroluminescence test instruction, taking the second photoluminescence spectrum as the first photoluminescence spectrum.

[0107] In other words, in the embodiments of the present application, the photoluminescence test of the tandem cell can be performed before the electroluminescence test, so that when performing the electroluminescence test provided by the present application, the second photoluminescence spectrum obtained during the photoluminescence test can be directly used as the first photoluminescence spectrum required for the electroluminescence test.

[0108] In some embodiments of the present application, please refer to Figure 6 , in step S400, determining the electroluminescence spectrum of the sub-cell to be tested according to the first photoluminescence spectrum and the measured light output spectrum of the sub-cell to be tested may include the following steps S410 to S430.

[0109] S410, obtaining the emission data of the sub-cell to be tested in the first photoluminescence spectrum as the first data.

[0110] S420, obtaining the emission data of the sub-cell to be tested in the measured light output spectrum as the second data.

[0111] S430, determining the electroluminescence spectrum of the sub-cell to be tested according to the data difference between the second data and the first data.

[0112] In the embodiments of the present application, by obtaining the first data of the sub-cell to be tested in the first photoluminescence spectrum and the second data in the measured light output spectrum, the second data and the first data can be subtracted from each other, so as to obtain the electroluminescence spectrum of the sub-cell to be tested. In this way, the electroluminescence spectrum of the sub-cell to be tested is obtained based on data processing, which can avoid the problems of misjudging the battery performance and the distribution of thin film morphological defects due to directly identifying the electroluminescence image of the solar cell, and is beneficial to improving the accuracy of the electroluminescence test of the tandem cell.

[0113] It is worth mentioning that, in some embodiments of the present application, the stacked cell includes a first end for connecting to the positive electrode of the test power supply and a second end for connecting to the negative electrode of the test power supply. The aforementioned sub-cell to be tested is the Nth sub-cell connected to the first end of the stacked cell, where N is a positive integer greater than or equal to 2. Correspondingly, please refer to Figure 7 , the solar cell detection method may further include the following steps S700 and S800.

[0114] S700, applying a second test electrical signal to the first end and the second end of the stacked cell.

[0115] S800, directly obtaining the electroluminescence spectrum of the first sub-cell connected to the first end of the stacked cell.

[0116] Here, the second test electrical signal may be the same as or different from the first test electrical signal, both are acceptable, and specifically, it can be selected and set according to the requirements.

[0117] In the embodiments of the present application, when performing electroluminescence tests on the second and subsequent other sub-cells connected to the first end of the stacked cell, the method of first obtaining the first photoluminescence spectrum and the test luminescence spectrum and then performing data processing in some of the foregoing embodiments can be adopted; while when performing electroluminescence tests on the first sub-cell connected to the first end of the stacked cell, the electroluminescence spectrum can be directly obtained. And, optionally, the electroluminescence test of the first sub-cell connected to the first end of the stacked cell can be performed prior to the electroluminescence tests of the second and subsequent other sub-cells, or it can also be performed after the electroluminescence tests of the second and subsequent other sub-cells are executed. The embodiments of the present application do not limit this.

[0118] It should be understood that Figures 1 to 7 the steps in the solar cell detection method shown in [[ ]] are expressed in sequence according to the step numbers, but these steps are not necessarily executed in the order of the step numbers. Unless there is a clear description in this article, the execution of these steps has no strict order limit, and these steps can be executed in other orders. Moreover, at least a part of each step may include multiple sub-steps or multiple stages, and these sub-steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these sub-steps or stages is not necessarily sequential, but can be executed alternately or alternately with at least a part of other steps or sub-steps or stages of other steps.

[0119] To more clearly illustrate the solar cell detection method provided by the embodiments of the present application, some possible implementation manners of the stacked cell are exemplarily provided in the following embodiments.

[0120] Exemplarily, please refer toFigure 8 , the tandem cell includes a perovskite sub-cell and a crystalline silicon sub-cell; wherein, the crystalline silicon sub-cell is located on the side of the perovskite sub-cell for connecting the positive electrode of the test power supply.

[0121] It can be understood that during the preparation and use of the tandem cell, the perovskite sub-cell is usually located at the top layer, and the crystalline silicon sub-cell is usually located at the bottom layer. In this way, the sunlight signal with the shortest wavelength can be first absorbed and utilized by the perovskite sub-cell, and then the sunlight signal with a longer wavelength can be transmitted into the crystalline silicon sub-cell for absorption and utilization, so as to convert light energy into electrical energy to the maximum extent. Figure 9 Exemplarily, a film layer structure of a tandem cell is provided. The tandem cell is a two-terminal perovskite / crystalline silicon tandem cell, including a crystalline silicon sub-cell 100, an intermediate composite layer 200, and a perovskite sub-cell 300 stacked in sequence. Among them, the crystalline silicon sub-cell 100 includes: a crystalline silicon absorption layer 110, a first passivation contact layer 120 disposed on the side of the crystalline silicon absorption layer 110 away from the intermediate composite layer 200, a second passivation contact layer 130 disposed on the side of the crystalline silicon absorption layer 110 close to the intermediate composite layer 200, and a transparent conductive layer 140 disposed on the side of the first passivation contact layer 120 away from the crystalline silicon absorption layer 110. The perovskite sub-cell 300 includes: a perovskite absorption layer 310, a hole transport layer 320 disposed on the side of the perovskite absorption layer 310 close to the intermediate composite layer 200, and a third passivation contact layer 330, an electron transport layer 340, a buffer layer 350, a conductive oxide layer 360, and an antireflection layer 370 stacked in sequence on the side of the perovskite absorption layer 310 away from the intermediate composite layer 200. Please continue to refer to Figure 9 , the tandem cell further includes a first electrode 400 connected to the transparent conductive layer 140, and a second electrode 500 connected to the conductive oxide layer 360.

[0122] Based on this, it can be understood that as a thin-film battery, the perovskite sub-cell 300 is prone to uneven film layer distribution. Assuming that a conventional electroluminescence test is performed on the perovskite sub-cell 300, due to the unevenness of the film layer distribution, it is easy to cause different breakdown voltages / breakdown currents corresponding to different parts of the perovskite sub-cell 300, that is: after applying the test voltage / test current, there may be a situation where a part of the perovskite sub-cell 300 has been broken down while other parts have not been turned on, resulting in an overexposed electroluminescence spectrum or abnormal brightening around the defect in the directly obtained electroluminescence spectrum, leading to misjudgment of the battery performance and the distribution of thin-film morphology defects of the perovskite sub-cell 300. Therefore, in the embodiments of the present application, when performing an electroluminescence test on the tandem battery, the crystalline silicon sub-cell is located on the side of the perovskite sub-cell that is used to connect the positive electrode of the test power supply, which is convenient for directly performing an electroluminescence test on the crystalline silicon sub-cell, while the perovskite sub-cell is subjected to an electroluminescence test by first obtaining the first photoluminescence spectrum and the test luminescence spectrum and then performing data processing, so as to accurately obtain the electroluminescence spectrum of the perovskite sub-cell.

[0123] Figure 10 Exemplarily provided is Figure 8 an equivalent circuit schematic diagram of the tandem battery shown. Please refer to Figure 10 , the crystalline silicon sub-cell can be equivalent to a first diode D1, the perovskite sub-cell can be equivalent to a second diode D2, and the intermediate composite layer between the crystalline silicon sub-cell and the perovskite sub-cell can be equivalent to a third diode D3 arranged in reverse. Thus, assuming that a conventional electroluminescence test is performed on the perovskite sub-cell, the third diode D3 needs to be reversely broken down to form a current path between the first diode D1 and the second diode D2. However, in the embodiments of the present application, taking the perovskite sub-cell as the sub-cell to be measured and the crystalline silicon sub-cell as the associated sub-cell, after applying a first excitation light to the tandem battery to excite the perovskite sub-cell and the crystalline silicon sub-cell to be in a luminous state, please refer to Figure 11 , the equivalent diodes of the perovskite sub-cell and the crystalline silicon sub-cell are both in a conducting state, and a power path of an equivalent current source can be formed beside the third diode D3 equivalent to the intermediate composite layer, so that the third diode D3 does not need to be reversely broken down, and the test luminescence spectrum of the perovskite sub-cell can be obtained, and data processing can be performed according to the first photoluminescence spectrum and the test luminescence spectrum of the perovskite sub-cell, so as to accurately obtain the electroluminescence spectrum of the perovskite sub-cell.

[0124] Exemplarily, please refer to Figure 12 , the tandem battery includes a first bandgap sub-cell and a second bandgap sub-cell; wherein, the bandgap of the first bandgap sub-cell is smaller than the bandgap of the second bandgap sub-cell, and the first bandgap sub-cell is located on the side of the second bandgap sub-cell that is used to connect the positive electrode of the test power supply.

[0125] Optionally, the first bandgap sub-cell includes, but is not limited to, a crystalline silicon sub-cell, a narrow-bandgap perovskite sub-cell, an organic solar sub-cell, a copper zinc tin sulfide thin-film sub-cell, or a copper indium gallium selenide thin-film sub-cell.

[0126] Optionally, the second bandgap sub-cell includes, but is not limited to, a wide-bandgap perovskite sub-cell.

[0127] In addition, optionally, the tandem cell includes multiple sub-cells with different bandgaps, where the bandgaps of the respective sub-cells vary from small to large along their stacking direction. During the preparation and use of this tandem cell, the sub-cell with the largest bandgap is usually located at the top layer, and the sub-cell with the smallest bandgap is usually located at the bottom layer. In this way, the sunlight signal with the shortest wavelength can be first absorbed and utilized by the sub-cell with the largest bandgap, and then the sunlight signals with gradually increasing wavelengths can be transmitted in and absorbed and utilized layer by layer by the sub-cells with gradually decreasing bandgaps, so as to convert light energy into electrical energy to the greatest extent. And when performing electroluminescence testing on this tandem cell, the first end where the sub-cell with the smallest bandgap is located is used to connect to the positive pole of the test power supply, and the second end where the sub-cell with the largest bandgap is located is used to connect to the negative pole of the test power supply.

[0128] It should be noted that in some embodiments, the bandgap range of the first bandgap sub-cell includes 1.0 eV to 1.2 eV, for example, it can be 1.0 eV, 1.1 eV, or 1.2 eV. The bandgap range of the second bandgap sub-cell includes 1.6 eV to 1.8 eV, for example, it can be 1.6 eV, 1.7 eV, or 1.8 eV.

[0129] Optionally, the bandgap range of the sub-cell to be measured includes 1.6 eV to 1.8 eV, for example, it can be 1.7 eV. The excitation spectrum range of the sub-cell to be measured is, for example, 300 nm to 800 nm, and the emission wavelength range of the sub-cell to be measured is, for example, 650 nm to 850 nm. The bandgap range of the associated sub-cell includes 1.0 eV to 1.0 eV, for example, it can be 1.1 eV. The excitation spectrum range of the associated sub-cell is, for example, 300 nm to 1100 nm, and the emission wavelength range of the associated sub-cell is, for example, 1000 nm to 1200 nm.

[0130] Correspondingly, the wavelength range of the first excitation light includes, but is not limited to, 300 nm to 650 nm, for example, it can be 530 nm. The target filter corresponding to the sub-cell to be measured can select light signals with wavelengths in the range of 600 nm to 800 nm to pass through.

[0131] Some embodiments of the present application also provide a solar cell detection system, which is applied to a stacked cell. The stacked cell includes at least two sub-cells stacked in sequence. This solar cell detection system is used to implement the solar cell detection method described in the above-mentioned some embodiments. The technical advantages of the foregoing solar cell detection method are also possessed by this solar cell detection system. In addition, the technical solutions involved in this solar cell detection system can also be understood in combination with the relevant content in the foregoing solar cell detection method, and will not be elaborated here.

[0132] Please refer to Figure 13 , the solar cell detection system includes: a controllable light source 10, a spectral acquisition device 20, and a detection and processing device 30.

[0133] The controllable light source 10 is configured to: emit a first excitation light to the stacked cell in response to an electroluminescence test instruction, and the first excitation light is used to at least excite the sub-cell to be measured and the associated sub-cell to be in a light-emitting state; wherein, the associated sub-cell and the sub-cell to be measured are arranged adjacent to each other in sequence along the sub-cell current transmission direction corresponding to the test electrical signal.

[0134] The spectral acquisition device 20 is configured to: acquire the first photoluminescence spectrum of the sub-cell to be measured in response to an electroluminescence test instruction, and acquire the test output light spectrum of the sub-cell to be measured in response to a first test electrical signal.

[0135] The detection and processing device 30 is connected to the controllable light source 10 and the spectral acquisition device 20, and is configured to: send an electroluminescence test instruction to the controllable light source; apply a first test electrical signal to the stacked cell in response to the sub-cell to be measured and the associated sub-cell being in a light-emitting state; and determine the electroluminescence spectrum of the sub-cell to be measured according to the first photoluminescence spectrum and the test output light spectrum of the sub-cell to be measured.

[0136] Optionally, the detection and processing device 30 determines the electroluminescence spectrum of the sub-cell to be measured according to the first photoluminescence spectrum and the test output light spectrum of the sub-cell to be measured, including: acquiring the light-emitting data of the sub-cell to be measured in the first photoluminescence spectrum as the first data; acquiring the light-emitting data of the sub-cell to be measured in the test output light spectrum as the second data; and determining the electroluminescence spectrum of the sub-cell to be measured according to the data difference between the second data and the first data.

[0137] In some embodiments of the present application, the controllable light source 10 is further configured to: emit a first excitation light that can excite each sub-cell to be in a light-emitting state to the stacked cell in response to an electroluminescence test instruction.

[0138] In some embodiments of the present application, a filter placement portion is provided on the light incident side of the spectral acquisition device 20; wherein, the filter placement portion is used to place the target filter. The target filter corresponds to the sub-cell to be measured one by one, and is configured to select the emitted optical signal passing through the sub-cell to be measured. Correspondingly, the spectral acquisition device 20 is configured to: respectively obtain the first photoluminescence spectrum and the test output light spectrum of the sub-cell to be measured based on the target filter.

[0139] In some embodiments of the present application, the detection and processing device 30 is further configured to: send a photoluminescence test instruction to the controllable light source 10. The controllable light source 10 is further configured to: emit a second excitation light to the stacked cell in response to the photoluminescence test instruction. The spectral acquisition device 20 is further configured to: obtain the second photoluminescence spectrum of the sub-cell to be measured in response to the photoluminescence test instruction.

[0140] Optionally, the wavelength of the second excitation light is the same as the wavelength of the first excitation light. Correspondingly, the spectral acquisition device 20 obtains the first photoluminescence spectrum of the sub-cell to be measured in response to the electroluminescence test instruction, including: in response to the electroluminescence test instruction, taking the second photoluminescence spectrum as the first photoluminescence spectrum.

[0141] In some embodiments of the present application, the stacked cell includes a first positive electrode end for connecting to a test power supply and a second negative electrode end for connecting to the test power supply. The aforementioned sub-cell to be measured is the Nth sub-cell connected to the first end, and N is a positive integer greater than or equal to 2. Correspondingly, the detection and processing device 30 is further configured to: apply a second test electrical signal to the first end and the second end of the stacked cell, so that the spectral acquisition device directly obtains the electroluminescence spectrum of the first sub-cell connected to the first end in response to the second test electrical signal.

[0142] In the description of this specification, the description with reference to terms such as "some embodiments", "some examples", "exemplarily", etc. means that the specific features, structures, materials or features described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic description of the above terms does not necessarily refer to the same embodiment or example.

[0143] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered to be within the scope described in this specification.

[0144] The above-described embodiments merely represent several implementation manners of the present application. The description thereof is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all fall within the protection scope of the present application.

Claims

1. A method for detecting a solar cell, applied to a tandem cell; The stacked cell includes: At least two sub-cells stacked in sequence; characterized in that the solar cell detection method includes: In response to an electroluminescence test instruction, obtaining a first photoluminescence spectrum of the sub-cell to be tested; Applying a first excitation light to the stacked cell to at least excite the sub-cell to be tested and the associated sub-cells to be in a light-emitting state; the associated sub-cells are arranged adjacent to the sub-cell to be tested in sequence along the sub-cell current transmission direction corresponding to the test electrical signal; Applying a first test electrical signal to the stacked cell to obtain a test emission spectrum of the sub-cell to be tested; Determining the electroluminescence spectrum of the sub-cell to be tested according to the first photoluminescence spectrum and the test emission spectrum of the sub-cell to be tested.

2. The solar cell detection method according to claim 1, wherein The associated sub-cell is located on the side of the sub-cell to be tested for connecting the positive electrode of the test power supply; the number of the associated sub-cells is one or more.

3. The solar cell detection method according to claim 1, wherein The step of applying the first excitation light to the stacked cell to at least excite the sub-cell to be tested and the associated sub-cells to be in a light-emitting state further includes: applying the first excitation light to the stacked cell to excite each of the sub-cells of the stacked cell to be in a light-emitting state.

4. The solar cell detection method according to claim 1, wherein, The wavelength of the first excitation light is within the excitation spectrum range of the sub-cell to be tested, and the wavelength of the first excitation light is greater than the excitation light wavelength of the associated sub-cell.

5. The solar cell detection method according to claim 1, characterized in that The first test electrical signal includes a test voltage and / or a test current; wherein, The value range of the test voltage includes: 0.1% - 200%, 0.1% - 120%, 0.1% - 100% or 5% - 30% of the open-circuit voltage of the stacked cell; The value range of the test current includes: 0.1% - 200%, 0.1% - 120%, 0.1% - 100% or 5% - 30% of the short-circuit current of the stacked cell.

6. The solar cell detection method according to claim 1, wherein Obtaining the first photoluminescence spectrum and the test emission spectrum of the sub-cell to be tested includes: Setting a target filter on the light incident side of the spectral acquisition device; wherein, the target filter corresponds to the sub-cell to be tested one by one, and the target filter is configured to select the outgoing light signal passing through the sub-cell to be tested; Based on the target filter, respectively obtaining the first photoluminescence spectrum and the test emission spectrum of the sub-cell to be tested.

7. The solar cell detection method according to claim 6, wherein It further includes: In response to a photoluminescence test instruction, applying a second excitation light to the stacked cell; Based on the target filter, obtaining a second photoluminescence spectrum of the sub-cell to be tested for the photoluminescence test.

8. The solar cell detection method according to claim 7, wherein The wavelength of the second excitation light is the same as the wavelength of the first excitation light; wherein, The step of, in response to an electroluminescence test instruction, obtaining a first photoluminescence spectrum of the sub-cell to be tested includes: in response to the electroluminescence test instruction, using the second photoluminescence spectrum as the first photoluminescence spectrum.

9. The solar cell detection method according to claim 1, wherein The step of determining the electroluminescence spectrum of the sub-cell to be tested according to the first photoluminescence spectrum and the test emission spectrum of the sub-cell to be tested includes: Obtaining the light emission data of the sub-cell to be tested in the first photoluminescence spectrum as first data; Obtaining the light emission data of the sub-cell to be tested in the test emission spectrum as second data; Determine the electroluminescence spectrum of the sub-cell to be measured according to the data difference between the second data and the first data.

10. The solar cell detection method according to claim 1, characterized in that, The tandem cell includes a first end for connecting to the positive electrode of a test power supply and a second end for connecting to the negative electrode of the test power supply; the sub-cell to be measured is the Nth sub-cell connected to the first end, where N is a positive integer greater than or equal to 2; wherein, the solar cell detection method further includes: Apply a second test electrical signal to the first end and the second end of the tandem cell. Directly obtain the electroluminescence spectrum of the first sub-cell connected to the first end.

11. The solar cell detection method according to any one of claims 1 to 10, characterized in that, The tandem cell includes a perovskite sub-cell and a crystalline silicon sub-cell; wherein, the crystalline silicon sub-cell is located on the side of the perovskite sub-cell for connecting to the positive electrode of the test power supply.

12. The solar cell detection method according to any one of claims 1 to 10, characterized in that, The tandem cell includes a first bandgap sub-cell and a second bandgap sub-cell; wherein, the bandgap of the first bandgap sub-cell is less than the bandgap of the second bandgap sub-cell, and the first bandgap sub-cell is located on the side of the second bandgap sub-cell for connecting to the positive electrode of the test power supply.

13. The solar cell detection method according to claim 12, wherein The bandgap range of the first bandgap sub-cell includes 1.0 eV to 1.2 eV; The bandgap range of the second bandgap sub-cell includes 1.6 eV to 1.8 eV.

14. The solar cell detection method according to claim 12, characterized in that, The bandgap range of the sub-cell to be measured includes 1.6 eV to 1.8 eV; the wavelength range of the first excitation light includes 300 nm to 650 nm.

15. A solar cell detection system is applied to a stacked cell, and the stacked cell includes: At least two sub-cells stacked in sequence; wherein, the solar cell detection system includes: A controllable light source configured to: emit a first excitation light to the tandem cell in response to an electroluminescence test instruction, the first excitation light being used to at least excite the sub-cell to be measured and the associated sub-cell to be in a light-emitting state; wherein, the associated sub-cell is arranged adjacent to the sub-cell to be measured in sequence along the sub-cell current transmission direction corresponding to the test electrical signal; A spectrum acquisition device configured to: acquire a first photoluminescence spectrum of the sub-cell to be measured in response to the electroluminescence test instruction, and acquire a test output light spectrum of the sub-cell to be measured in response to a first test electrical signal; A detection and processing device, connected to the controllable light source and the spectrum acquisition device, configured to: send the electroluminescence test instruction to the controllable light source; in response to the sub-cell to be measured and the associated sub-cell being in a light-emitting state, apply the first test electrical signal to the tandem cell; and determine the electroluminescence spectrum of the sub-cell to be measured according to the first photoluminescence spectrum and the test output light spectrum of the sub-cell to be measured.

16. The solar cell detection system according to claim 15, characterized in that, The controllable light source is further configured to: emit the first excitation light that can excite each of the sub-cells to be in a light-emitting state to the tandem cell in response to the electroluminescence test instruction.

17. The solar cell detection system according to claim 15, wherein A filter placement part is provided on the light incident side of the spectrum acquisition device; wherein, The filter placement part is used to place a target filter; the target filter corresponds to the sub-cell to be measured one by one and is configured to select the output light signal passing through the sub-cell to be measured. The spectral acquisition device is configured to: respectively obtain the first photoluminescence spectrum and the measured light output spectrum of the sub-cell to be measured based on the target filter.

18. The solar cell detection system according to claim 17, wherein the detection and processing device is further configured to: send a photoluminescence test instruction to the controllable light source; the controllable light source is further configured to: emit a second excitation light to the stacked cell in response to the photoluminescence test instruction; the spectral acquisition device is further configured to: obtain a second photoluminescence spectrum of the sub-cell to be measured in response to the photoluminescence test instruction.

19. The solar cell detection system according to claim 18, characterized in that, The wavelength of the second excitation light is the same as the wavelength of the first excitation light; wherein, the spectral acquisition device obtains the first photoluminescence spectrum of the sub-cell to be measured in response to the electroluminescence test instruction, including: in response to the electroluminescence test instruction, using the second photoluminescence spectrum as the first photoluminescence spectrum.

20. The solar cell detection system according to any one of claims 15 to 19, characterized in that, The stacked cell includes a first end for connecting to the positive electrode of the test power supply, and a second end for connecting to the negative electrode of the test power supply; the sub-cell to be measured is the Nth sub-cell connected to the first end, where N is a positive integer greater than or equal to 2; wherein the detection and processing device is further configured to: apply a second test electrical signal to the first end and the second end of the stacked cell, so that the spectral acquisition device directly obtains the electroluminescence spectrum of the first sub-cell connected to the first end in response to the second test electrical signal.

Images