Toward Circular Energy: Recycling End-of-Life Solar Panels and Lithium-Ion Batteries for the Development of Lithium–Silicon Batteries

The growing deployment of renewable energy systems has raised concerns about the end-of-life management of their components, particularly photovoltaic (PV) panels and lithium-ion batteries. These two waste streams contain valuable materials such as high-purity silicon and lithium, which are critical for energy storage technologies. This study explores a circular approach by recovering silicon from used solar cells and lithium from spent batteries to fabricate lithium–silicon (Li–Si) batteries, known for their high theoretical capacity and potential to replace conventional graphite-based lithium-ion batteries.

The methodology involves the extraction and purification of silicon from photovoltaic cells through a multi-step process, including chemical etching, thermal treatment, and acid leaching. Simultaneously, lithium is recovered from lithium-ion battery cathodes using hydrometallurgical techniques. The purified silicon is then used as an anode material in a prototype lithium–silicon battery. Characterization techniques such as SEM, XRD, and FTIR are employed to analyze the morphology and purity of the recovered silicon.

Preliminary results show the promising purity levels and structural integrity of the extracted silicon, which meets the basic requirements for battery-grade materials. The study demonstrates the feasibility of transforming waste into high-value components while addressing environmental concerns and supply chain risks.

This project contributes to the development of sustainable, closed-loop energy systems by integrating waste management and battery innovation, supporting both circular economy principles and climate change mitigation strategies.