Spectrally resolved electrical model for c-Si, CIGS, and perovskite solar cells in tandem configuration

The PV industry has shifted its focus on the tandem solar cells as next generation devices expected to reach the market in the next 5-8 years. The tandem solar cell combines two PV technologies in different combinations to achieve maximal spectral utilization and boost device efficiency beyond 25%. Multiple combinations such as silicon/CIGS or silicon/perovskite are already showing promising results that it could be a commercialized in few years [1]. Imec is at the forefront of this research field with in-house fabricated tandems reaching 27.1% efficiency with silicon/perovskite tandem cells. Physics based modelling of these devices are very important to understand their performance in outdoor conditions, to improve their design and maximize their utilization. However, the complex behaviour of thin-film semi-conductors makes this research a challenge with many open questions.

At IMEC, we have developed highly accurate energy yield models for single junction c-Si and CIGS solar cells. The tandem PV use different technologies together to absorb different parts of the solar spectrum for maximizing spectral utilization. There are already few studies where CIGS solar cells have distorted IV performance when subjected to only red part of the spectrum. There is a need to study how the electrical response varies when a cell is subjected to only a part of the solar spectrum as the existing model considers the intensity of the solar spectrum as an input.

So, the objectives of this thesis are:

1. Measure the IV curve distortions in the electrical performance of thin-film PV technologies when subjected to a part of the solar spectrum.
2. Establish if there is a need for detailed spectrum based electrical modelling approach.

The candidate will be working on a novel research that will establish the modelling and designing strategy for the tandem PV devices and the candidate has an opportunity to gain experience in IMEC’s industrial grade infrastructure.

Tools to be used:

1. PV cell/module characterization tools – Solar simulators
2. IMEC’s patented energy yield simulation framework.
3. Numerical simulation tools like Quokka or ADEPT or SCAPS