Solar Cell Testing Tool Solar cell testing tool comprising of A. Solar simulator •Type of Solar simulator: Up shine configuration, AM 1.5G, Class AAA Up shine: The uniform light should be illuminated in upward direction. The solar cell will be placed on the quartz plate with top contact arrangement. AM 1.5G: Air mass 1.5G filter giving 1 Sun output power (100 mWatt/cm2) with standard solar spectrum. Class AAA: Verified by IEC, ASTM, and JIS standards Class A Spectral Performance: The spectrum should match (≤ ± 15%) with the standard solar spectrum over 300 – 1200 nm wavelength range. Class A Spatial Non-uniformity performance: The light should be uniform over 156 mm2 area with non-uniformity irradiance < 2%. Class A Temporal Instability: Maximum temporal instability ≤ 0.5%. •Beam Size: 156 mm x 156 mm square area (class AAA performance required over the entire 156 mm x 156 mm square area). •Built-in constant intensity feedback circulatory to maintain intensity of light at desired level •High grade shutter system to allow zero light leakage when shutter is off. •Lamp Specification: Lamp type: Xenon short arc lamp (Ozone free). Wattage: 1000W B. Current-Voltage (I-V) measurement tool with software: The I-V measurements should be done in 4 wire configuration and I-V should be verified by standard solar research group. The current range for source measure unit (SMU) should be up to 20 A. The system should be capable of measuring all types of solar cells and should give following cell parameters 1. Short circuit current (Isc) 2. Current density (Jsc) 3. Open circuit voltage (Voc) 4. Fill factor (FF) 5. Maximum current (Imax) 6. Maximum voltage (Vmax) 7. Maximum power (Pmax) 8. Efficiency (η) 9. Series resistance (Rs) 75,500 each 1.000 75,500 10. Shunt resistance (Rsh) The I-V software should provide the following functions: 1. The software should provide the normalize I-V curve corrected to 1 sun intensity and STC temperature conditions. 2. Dark current measurements of solar cells (dark IV) in forward and reverse bias modes. The dark current of the order of few nA should be able to measured using current source measure unit provided with the system.
3. Should have the capability of determination of diode quality factor by I-V measurements as a function of light intensity. (A reference solar cell should be provided with the system for calibration of solar simulator light intensity) C. Test Fixture for Solar Cell Four micro manipulators (magnetic-demagnetized switch type) enabling easy top contacts on the different size solar cells. The metal bracket arrangement should be provided around the solar simulator window for placement of the macro manipulators. The standard low resistance probes with tip diameter around 1 mm should be provided with the test fixture.
