Epishine in Sweden has launched its low cost flexible organic solar cell technology for indoor use after a decade of development.
The cell is aimed at powering sensors and actuators, including electronic locks, from indoor LED and fluorescent light
“This is a historic day for Epishine,” said Anna Björklou, CEO of Epishine. “ It has taken over 25 years of research and we have developed a production process scalable to large volume. It has been optimised for indoor use, which is why we call it a Light cell rathe thana solar cell.”
The first production version uses a non-fullerene polymer that gives a conversion efficiency of 15 percent with an output of 0.5V and is tuned to indoor light at 400 to 700nm at 20 to 1000lux. The company is working on a version with higher efficiency of 26 per cent using a fullerene material, says Jonas Bergqvist, CTO.
The key is a lamination technology for building the thin cells with recycled plastic materials. “We have developed a method to use lamination instead of sequential printing. We print on two halves and use temperature and pressure to bond the two layers,” said Bergquist. “What is critical for large scale deployment is a high up time so it is important to handle the lower corner cases, down to 50lux. This is especially true in the home environment.”
The cell is aimed for indoor use as the currents generated in outdoor conditions would be too high for the electrodes, he said.