The Influence of Heating Time and Temperature on the Properties of CIGSSe Solar Cells

Abstract

Nonencapsulated CIGSSe solar cells, with a silver grid, were exposed to different temperatures for various periods in order to measure the effect of the heat exposure in CIGSSe modules. The heat treatment time and temperature were varied during the experiments, which were executed at atmospheric conditions. In all the cases, after reaching a temperature of about 300°C, theIVmeasurement showed a reduction of 2-3% in terms ofVOCandJSC. This is confirmed, respectively, by Raman and EQE measurements as well. The efficiency drop was −7%, −29%, and −48%, respectively, for 30 seconds, 300 seconds, and 600 seconds of exposure time. With temperatures larger than 225°C, the series resistance starts to increase exponentially and a secondary barrier becomes visible in theIVcurve. This barrier prevents the extraction of electrons and consequently reducing the solar cells efficiency. Lock-in thermography demonstrated the formation of shunts on the mechanical scribes only for 300 and 600 seconds exposure times. The shunt resistance reduction is in the range of 5% for all time periods.

Decay mechanisms in CdS‐buffered Cu(In,Ga)Se2 thin‐film solar cells after exposure to thermal stress: Understanding the role of Na

“…Above the critical annealing temperature, the degradation of the devices hinges on the total heating flux (see Figure 3). This observation is in line with the results shown by Flammini et al 22 It is obvious that annealing at 300°C for 20 min is extremely damaging for the complete solar cells of both kinds. Therefore, for this study, these experimental stress conditions were chosen, to study and determine the causes why the various devices degrade under thermal stress.…”

Analysis of temperature distribution in a solar element with posistor layer in the presence of local electric heat source

“…Taking into account that the process of reaching temperatures sufficient for thermal breakdown of the considered silicon solar cells lasts about several tens of seconds [19], and the stay of such photovoltaic cells at temperatures below 300 С for several hours does not lead to their significant degradation [19][20][21][22], the obtained results substantiate the prospects of using the built-in posistor layer for electrical and thermal protection of solar photovoltaic cells from reverse overvoltages.…”

Post‐mortem analysis of a commercial Copper Indium Gallium Diselenide (CIGS) photovoltaic module after potential induced degradation

“…There was no power degradation; on the contrary, a slight increase in module performance was noted. A possible explanation is the effect of thermal annealing during the heat exposure 22 . Hence, the power losses in PID‐tested module can be attributed to the additional bias application during the test.…”

“…A possible explanation is the effect of thermal annealing during the heat exposure. 22 Hence, the power losses in PID-tested module can be attributed to the additional bias application during the test. We have performed GD-OES on selected samples to investigate if and at which layers sodium accumulated and whether we see a correlation between the degradation of electrical properties and the difference in sodium content.…”