Manual Solar Cell EL+IV Combo Tester

The Manual Solar Cell EL+IV Combo Tester is a benchtop device integrating Electroluminescence (EL) defect detection and Current-Voltage (IV) characteristic testing functionalities. Designed for laboratories, R&D centers, or small-batch production environments, it efficiently performs quality assessment and performance analysis on individual solar cells.

Product Features

• 1. Integrated Functions: Performs two critical performance and quality tests on a cell in one device.

• 2. Manual Operation: Operators manually place the cell under test on the probe station/stage within the testing area and manually manipulate probes or pressure plates to ensure good electrical contact with the cell's electrodes.

• 3. IV Testing: The device applies simulated sunlight (typically via a pulsed or steady-state light source) to the cell and precisely measures its response under different voltage/current conditions, generating an I-V curve. This yields key parameters such as Open-Circuit Voltage (Voc), Short-Circuit Current (Isc), Maximum Power Point (Pmax), Fill Factor (FF), and Conversion Efficiency (η).

• 4. EL Testing: Under darkroom conditions (the device usually has a built-in light shield), a forward bias current is applied to the cell, causing it to emit near-infrared light. The high-sensitivity camera built into the device captures this luminescence, generating an EL image. The image clearly reveals internal defects and process issues such as micro-cracks, broken fingers, chips, black cores, black spots, sintering defects, shunt resistance, material inhomogeneity, etc.

• 5. Compact & Efficient: The integrated design saves space and simplifies the workflow. After testing, the device software provides both an IV parameter report and an intuitive EL defect image, facilitating rapid analysis of cell quality and performance.

Technical Specifications

Applications

• 1. PV R&D & Process Optimization: Evaluate performance and defects of new cell materials/structures, optimize key processes (texturing, diffusion, passivation, coating, sintering, printing), and conduct failure mechanism studies.

• 2. PV Education & Experimentation: Provides a practical platform for universities and vocational education, visually demonstrating solar cell working principles, performance parameters, common defects, and their impact.

• 3. Production QC & Incoming Inspection: Serves small/medium-sized cell/module factories for sampling/full inspection of trial batches or high-value cells, defect screening and performance verification of supplier materials, and rapid troubleshooting of production line process anomalies.

• 4. Third-Party Testing & Certification: Provides independent, authoritative cell EL defect detection and IV performance calibration services for testing and certification bodies, used for sample analysis or dispute arbitration.

• 5. Module After-Sales & Failure Analysis: Locate problematic cells within failed modules, analyze the causes of their internal defects (EL) and performance degradation (IV), guiding repair or improvement.

Precautions

• 1. Strict Grounding: Ensure the device power supply is properly grounded. Wear insulated gloves during operation to prevent electric shock.
• 2. Handle Cells Carefully: Cell edges are sharp and fragile. Wear anti-cut gloves, handle gently, and clean fragments promptly to prevent cuts.
• 3. Avoid Direct Light Source Viewing: Do not look directly at the strong pulsed or steady-state light source used for IV testing to prevent eye damage.
• 4. Gentle Operation to Prevent Damage: Operate probes or pressure plates gently. Avoid excessive force to prevent damaging the equipment or crushing the cell. Keep hands away from moving parts during operation.
• 5. Precise Cell Placement: When placing the cell manually, ensure it is flat, centered, and the electrode orientation strictly corresponds to the probe position.
• 6. Ensure Reliable Electrical Contact: Carefully operate to establish stable, low-resistance contact between probes/pressure plates and the cell electrodes. Poor contact is the main cause of inaccurate IV results.
• 7. Maintain Cleanliness: Keep the device surface, stage, probe tips, the cell itself, and the EL camera lens/viewport clean, free of dust, fingerprints, and oil stains.
• 8. Complete Darkness Required for EL Test: Before performing EL testing, ensure the device light shield is fully closed with no light leakage inside.
• 9. Correct Parameter Settings: Set IV (light intensity, scan range, speed) and EL (bias current, exposure time) test parameters accurately according to the cell type (e.g., PERC, TOPCon, HJT, IBC) and specifications. Incorrect settings can lead to invalid results or cell damage.
• 10. Recommended Test Sequence: Typically perform IV testing first, followed by the EL test which requires power application.
• 11. Regular Cleaning & Maintenance: Frequently clean probe tips (with anhydrous alcohol), stage, inside of light shield, and EL camera lens (carefully with specialized tools).
• 12. Inspect & Replace Probes: Regularly inspect probes for wear, bending, or oxidation. Replace promptly to ensure good contact.
• 13. Regular Light Source Calibration (IV): Calibrate the IV test light source intensity to the standard value (e.g., 1000 W/m²) as recommended by the manufacturer or based on usage frequency to ensure accuracy of parameters like efficiency.
• 14. Regular Camera Calibration (EL): Periodically check EL camera focus and uniformity. Calibrate if necessary (e.g., flat field correction) to ensure image quality.
• 15. Perform System Calibration: Conduct periodic overall calibration of the device's electrical measurement accuracy and spatial positioning as required by the manual.
• 16. Check Contact First When Interpreting IV Results: When analyzing IV data, first check if the curve is smooth without steps. Abnormalities usually stem from contact issues.
• 17. Monitor Ambient Temperature: Maintain relatively stable lab temperature (recommended 25±2°C). Temperature changes affect cell performance (especially Voc).
• 18. EL Image Interpretation Requires Expertise: EL image analysis requires professional knowledge to distinguish real defects (micro-cracks, broken fingers, black cores, etc.) from image artifacts (noise, uneven illumination).
• 19. Monitor Light Source Lifespan: IV test light sources (Xenon/LED) have a finite lifespan. Monitor light intensity decay and replace timely.
• 20. Monitor Probe Lifespan: Probes are consumables. Replace them regularly based on usage intensity.
• 21. Understand Device Limitations: This device is suitable for manual single-cell testing with limited speed. EL detection resolution determines the smallest identifiable defect size.
• 22. Operator Training Required: Operators must receive adequate training and be qualified before operating the device.