3 Terminal Perovskite/Silicon Tandem Solar Cells
Our research focuses on the integration of silicon bottom solar cells featuring interdigitated back contacts (Si IBC) and perovskite top cells into highly efficient 3-terminal tandem devices. This tandem device approach is very tolerant towards spectral variations, mitigates the impact of different degradation behaviors of the two sub-cells. Therefore, at ipv, we have fabricated and characterized first Si IBC bottom cells with different front and rear side morphology and have compared their performance. Then, we deposited wide band gap (~1.7 eV) perovskite top cells wet-chemically directly onto the front surface of the Si IBC bottom cells. Conformal wet-chemical deposition of the perovskite top cell on Si bottom cells with ~5micrometre wide-sized pyramids is challenging and displays the main bottleneck for our 3T perovskite/silicon tandem cell development. The uniform intermediate layers will allow fabrication of shunt-free tandem solar cells, thus help us to further optimize the 3T device.
Status: Ongoing
Date of proposal: 28/02/2025
Start date: 03/10/2022
End Date: 07/10/2022
Used Instruments: Not explicitly mentioned but likely includes typical equipment for solar cell fabrication and testing.
Experimental Technique: Fabrication of 3-terminal (3T) perovskite/Si tandem solar cells. Comparison of wet-chemically deposited perovskite with evaporated perovskite top cells. Performance analysis of tandem devices with reverse and series connected cells.
Experiment Description: The project aimed at fabricating 3T perovskite/Si tandem devices with different perovskite top cells and n-type Si IBC (interdigitated back contacts) solar cells. The main focus was on comparing chemically deposited and evaporated perovskite cells and analyzing the performance of these 3T tandems.
Type Samples: 3T perovskite/Si tandem solar cells.
Sample Description: Seventeen 3T tandem cells, including wet-chemically and hybrid p-i-n perovskite top cells. IBC bottom cells and new 1cm2 cell designs.
Experiment Data Type: Performance data of tandem devices (efficiency, voltage, current, etc.)
Characterization Technics: Performance characterization under standard test conditions. Current-voltage (J-V) measurements.
Characterization Data Type: J-V characteristics. Efficiency and performance parameters of tandem cells.
Analyzed Data: Comparison of tandem cells with different top cell fabrication techniques. Performance metrics of the 3T tandem cells like Voc, Jsc, FF, and ?, differences in performance based on cell configuration, and insights into the suitability of different perovskite deposition methods. Analysis of shunt formation and overall device efficiency.
Main Targets Project: Fabricating and evaluating the performance of 3T perovskite/Si tandem solar cells. Assessing the suitability of chemically deposited and evaporated perovskite top cells.
Main Achievements Findings: Successful fabrication of shunt-free 3T tandem devices with both wet-chemically and hybrid perovskite top cells, though hybrid cells achieved higher efficiency. The IBC bottom cells and the 1cm2 cell design are well-suited for tandem integration. Need identified for passivation of the front contact to improve bottom cell performance. The n-i-p perovskite top cell structure in 3T with reverse connected subcells is more prone to shunt formation.
Review 10
How would you describe your experience with the VIPERLAB opportunity? How did the experience/visit at EPFL PV-LAB meet your expectations?
It was a great opportunity to get some experiments at EPFL via VIPERLAB. I had very good impressions through all process.
Did you face any difficulties during your visit or application process?
On the 2nd day of my visit I was Corona positive.
Does this VIPERLAB experience at EPFL PV-LAB bring you closer to your research objectives? How?
Yes absolutely. Thanks to the experiments done at EPFL, I had a chance to evaluate my results and see the potential of my research topic.
What other VIPERLAB activities have you participated in, or would you like to participate in?
I haven’t participated in any other VIPERLAB activities but I recommended it to many colleagues and I would like to plan one more again in the future.
Do you intend or already did publish/present your collected results in a paper or conference?
Yes, I used some of the results in my poster for TandemPV 2023 Workshop.