A Solution To Perovskite Solar Cell Scalability Problems

Scientists at EPFL have found a way to overcome power loss and the manufacturing complexity of scaling up perovskite solar cells.

Perovskites are a hybrid material made of metal halides, organic compounds and other materials. Because of their light-harvesting capabilities and low manufacturing costs, they are prime candidates to overtake their silicon counterparts in the solar energy market. Perovskites have great potential for a variety of applications, including LED lights, lasers and photodetectors.

Perovskite solar cell commercialization is hampered by the fact that they are difficult to scale up. This causes a loss in power conversion efficiency and operational stability. This is caused by natural defects in perovskite’s molecular structure that interfere with electron flow. This causes “resistive Loss”, a power loss caused by resistance. Complex processes are required to produce high-quality, large-area perovskite film.

Scientists led by Mohammad Nazeeruddin from EPFL discovered a way to scale up the scaling problems of perovskites in a new study. Scientists have created a simple solvothermal process that can create single-crystalline titanium dioxide Rhombohedral nanoparticles. These can then be used to make a perovskite movie.

This new structure has a lower number of mismatches between “lattice”, which refers to the ladder-like structure of titanium dioxide nanoparticles. This means that there are fewer defects which results in better electron flow and lower power loss.

The scientists tested the small-sized, nanoparticle-based solar cells and achieved power conversion efficiency of 24.05%, and fill factor (a measure the actual obtainable power) at 84.7%. After continuous operation for 1400hrs, the cells retain approximately 90% of their initial performance.

Large-area cells were also manufactured by the scientists, who certified an efficiency rate of 22.72% and an active area of almost 24 cm2. These “represent the highest efficiency modules without the greatest loss in efficiency when scaling down,” concluded the authors.