Recycled silicon boosts lithium battery efficiency in new study

In a significant breakthrough, scientists from China have developed a new type of lithium battery using recycled materials from discarded solar panels, potentially revolutionizing battery technology.

This innovative approach addresses both the environmental impact of waste and the limitations of current lithium-ion batteries, Caliber.Az reports, citing foreign media.

The research, conducted by the Qingdao Institute of Bioenergy and Bioprocess Technology, introduces silicon-based anodes combined with a novel electrolyte. The new batteries, detailed in a paper published in Nature Sustainability on July 16, demonstrate a notable improvement in energy density compared to traditional graphite anode batteries. While conventional lithium-ion batteries with graphite anodes reach an energy density ceiling of about 300 watt-hours per kilogram, the silicon-anode batteries achieved 340 watt-hours per kilogram, significantly surpassing this limit.

The use of silicon as an anode material represents a considerable advancement. Silicon’s higher capacity compared to graphite makes it a promising alternative, offering the potential to enhance energy density by over 35 per cent. Silicon, being the second most abundant element in Earth's crust, is more accessible than graphite, which is primarily sourced from China. The recent export restrictions imposed by China on graphite have highlighted the need for alternative materials. The Qingdao team’s approach not only addresses the supply chain issues but also contributes to environmental sustainability by recycling silicon from old solar panels.

Despite its advantages, silicon has faced challenges in battery applications due to issues like mechanical fracturing. The researchers addressed these challenges by using micro-sized silicon particles and incorporating a flexible solid-electrolyte interphase to mitigate the impact of these issues. This innovation significantly improves the stability and performance of the silicon anodes, even under extreme temperatures ranging from -10 to 55 degrees Celsius.

Dong Tiantian, co-first author of the study, emphasized that this recycling strategy not only reduces the economic and environmental impacts associated with photovoltaic waste but also lowers the cost of lithium-ion batteries. Liu Tao, another co-first author, added that this work presents a more sustainable source for silicon particles and helps overcome major obstacles in the use of silicon anodes.

The potential applications of this technology are vast. Cui Guanglei, a professor at the Qingdao Institute, expressed optimism about the impact of this development on both electric vehicles and grid-scale energy storage. By demonstrating that high-performance, environmentally friendly lithium-ion batteries are feasible, the research paves the way for more sustainable energy solutions in the future.