IEC 63202-1-2019 pdf free.Photovoltaic cells – Part 1: Measurement of light-induced degradation of crystalline silicon photovoltaic cells.
A minimum of twenty PV cells is required for this test. Additional cells can be tested to makeup for any mechanical or handling damaged samples.
Under normal sampling criteria,test cells are randomly selected from the same sorting binand the same production batch. If cells are to be selected using a special sampling criterion,the detailed sampling specification shall be included in the final report.All samples for thistest shall be assigned a unique identification number for tracking and reporting purpose.
Selected PV cells shall be stored in a sealed and dark container immediately after l-vmeasurements to minimize the ambient light exposure.
6 Procedure for conditioning and evaluation
6.1 Following the procedures required in IlEC 60904-1, measure the I-V curve of each cellat STC.Each measurement shall be repeated three times. Calculate the intermittent power,P,(n=0,1,2…), as the average of the maximum power reading from the three I-V curves.Between each measurement,the cell shall be rested for more than 3 s, to allow the celltemperature to recover to its initial value.The contacting scheme for cell testing should not bechanged or disturbed during this test.The repeatability of these three readings shall be betterthan 0,2 %.
6.2 Place the sampled cells in the test chamber (Clause 4b), and expose all the sampledcells to solar simulator 2 with an irradiance of (1 000 ± 50) W/m2.To compensate for spatialnon-uniformity, it is recommended to systematically rotate cells to different locations in thechamber between exposure cycles.During light exposure, the temperature of all cells shall bemaintained within the range of (60 ±5)°c.
6.3 After the exposure described in Step 6.2 is cumulated to 5 kWh/m, repeat Step 6.1.
To practically simplify the overall test, 5 kWh/m is recommended for the first cycle instead of 1kWh/m2.This first cycle exposure may be adjusted based on cell technology or desired testconditions.
A similar formula and method are used for determining the magnitude of change of Imp
Where applicable,a similar formula and method can also be used for cell efficiency n andother parameters.
When one particular test cell reaches the above mentioned LlD quasi-stabilization condition,its data for the last 1-V measurements shall be properly recorded,and the cell shall be exemptfrom further testing.
6.6 For samples that do not achieve quasi-stabilization, as defined in Step 6.5, repeatStep 6.2 to a light exposure of 1 kWh/m2, and the repeat Step 6.1.
6.7A sample is exempt from further testing when either of the following conditions is met:
a) LID quasi-stabilization, as defined in Step 6.5, has been achieved, or
b) Cumulative exposure has reached 20 kWh/m2.
6.8The test terminates when all cells are exempt from further testing. All data shall berecorded properly for the final report.
When the purpose of the test is to observe LIlD performance,the test may be continuedbeyond 20 kwh/m2.
6.9lt is recommended to conduct the test without time delay between cycles; otherwise,put the samples at room temperature (25 °C± 5 °C) in a dark container,which is sealed orwith nitrogen gas purging.
6.10 Periodic electroluminescence (EL) testing of the samples is recommended to determinewhether or not cells are damaged due to repeated handling. lf any damage is observed, byeither EL test or other ways, the data shall be specially marked in the final report.IEC 63202-1 pdf download.