Deakin researchers find key solution to recycling solar panels
Post date: 23/10/2019 - 10:31
Researchers from Deakin's Institute for Frontier Materials has found a way to extract silicon from discarded solar panels and repurpose it into nano-silicon for batteries, »solving the biggest problem that is preventing photovoltaic cells from being recycled«. According to the University, material scientists Mokhlesur Rahman and Ying (Ian) Chen pioneered the investigation to recover silicon from waste solar panels and then nano-size it, ready for use in lithium-ion batteries. They say this is key to repurposing discarded solar cells and will prevent high-value waste from going to landfill.
»Although silicon semiconductors make up a relatively small part of solar panel cells, the material's value is extremely high. Scientists have been looking for ways to repurpose the silicon for some time and we believe this to be the missing piece of the puzzle,« Rahman said.
According to the researchers, the average service life of a solar panel is between 15 to 25 years. Modelling shows that, without a silicon recycling process, by 2050 there will be around 1.5 million tonnes of solar panel waste in landfill - the equivalent of around 100,000 small cars. The bulk of a solar panel is made up of glass, metal and plastic materials while, crucially, a small part is made from silicon. »Silicon cells are the most important component of a solar panel, transferring the sun's energy into electrons. They are also a high-value material being a chemical element and far too precious to end up as waste, which is why this finding is significant,« Chen said. Repurposed silicon can make high-energy anodes, the transporters moving electrons around inside a battery, with many automotive companies and battery manufacturers stockpiling the material for future use as the global appetite for advanced lithium-ion batteries increases. Battery grade nano-silicon is highly expensive and retails for more than $44,000 per kilogram.
The project has been directly supported by Institute for Frontier Material's Circular Economy Strategy Lead, Catherine McMahon, in collaboration with Deakin Research Innovations' Senior Commercial Manager Andrew Rau and industry partner Delaminating Resources Melbourne.