Quantum efficiency test method of perovskite/silicon tandem photovoltaic cells
1Key Takeaways
This document specifies the test method for the quantum efficiency of perovskite/crystalline silicon tandem solar cells, covering requirements for test equipment, pre-test preparation, quantum efficiency measurement procedures, and test reporting. It applies to the quantum efficiency testing of perovskite/crystalline s…
2Expert Interpretation
This paper provides a detailed interpretation of the SJ/T 12185-2026 standard, introducing the instrumentation, testing procedures, data processing, and correction methods for quantum efficiency testing of perovskite/crystalline silicon tandem photovoltaic cells, applicable to both two-terminal and four-terminal structures.
Standard Overview
SJ/T 12185-2026 "Test Method for Quantum Efficiency of Perovskite/Crystalline Silicon Tandem Photovoltaic Cells" was issued by the Ministry of Industry and Information Technology and came into effect on December 1, 2026. Targeting the rapidly developing technology of perovskite/crystalline silicon tandem solar cells in recent years, this standard specifies a standardized testing procedure for external quantum efficiency (EQE) to ensure the comparability and accuracy of test results.
Test Objects and Equipment
The standard defines two types of test objects: two-terminal tandem photovoltaic cells (two-terminal series connection) and four-terminal tandem photovoltaic cells (four-terminal independent). Test equipment must meet the requirements of Chapter 6 of IEC 60904-8:2014 and be equipped with a bias light source (such as an LED array or filter combination) and an external bias power supply. Four-terminal test equipment can be relatively simpler but requires independent connections to each sub-cell.
Pre-test Preprocessing
The cells under test must undergo light preconditioning using a solar simulator meeting IEC 60904-9:2020 Class CCC or higher, with an irradiance of 700~1300 W/m², for a duration of ≥3 minutes to stabilize cell performance.
Comparison of Testing Methods
| Structure Type | Test Mode | Bias Light Source Setting | Bias Voltage | Key Precautions |
|---|---|---|---|---|
| Two-terminal tandem | AC mode (recommended) | When measuring the top cell, strong light saturates the bottom cell; when measuring the bottom cell, the situation is reversed | Top cell: negative open-circuit voltage; Bottom cell: 1/2 of open-circuit voltage (requires adjustment) | Effects of transmission, shunting, and luminescence coupling influence; corrections are required |
| Four-terminal tandem | DC or AC | No bias light source required | No bias voltage | Measure each sub-cell separately; no coupling interference |
Detailed Testing Steps
Using two-terminal tandem cells as an example, the testing steps are: 1) Preheat and stabilize the light source; 2) Control temperature at (25±2)°C; 3) Calibrate the standard detector; 4) Measure the perovskite sub-cell: apply bias light to saturate the crystalline silicon sub-cell, set the bias voltage to the negative open-circuit voltage, and record the quantum efficiency; 5) Measure the crystalline silicon sub-cell: use bias light to saturate the perovskite sub-cell, adjust the bias voltage to the correct value (determined via the constant current method and zero response method), and record the quantum efficiency; 6) Data processing and correction.
Data Processing and Correction
Quantum efficiency data for two-terminal tandem cells requires shunt correction (see Standard Formula 1) and, if necessary, correction for transmission and luminescence coupling effects (Appendix A). The DC mode can serve as a supplement to evaluate performance under actual operating conditions. For four-terminal tandem cells, simply sum the data from each sub-cell.
Test Report Requirements
The report must include sample information, test conditions, preconditioning conditions, environmental conditions, EQE curves for each sub-cell, and short-circuit current density. For four-terminal cells, an overall EQE curve must also be provided.
The implementation of this standard will standardize the performance testing of perovskite/crystalline silicon tandem cells, promoting technological development and industrial application.