A holistic review on lithium-ion battery direct recycling from electrolyte to electrodes

Lithium-ion batteries (LIB) present a global challenge in managing their end-of-life (EOL). As LIB's raw materials are critical and valuable, they are considered a secondary resource. The annual volume of publications and patents on LIB recycling has significantly increased up to 32% compared to 4% in all scientific chemical literature for a decade since 2010, reflecting the emergence of this research topic. In a circular economy context, achieving high recycling efficiency of all LIB components and reusing recycled raw materials for battery production is essential. The increase in recycling efficiency is further promoted by governmental regulations aiming for a carbon neutrality and sustainable society with lower environmental impact. Conventional and destructive recycling methods, pyrometallurgy and hydrometallurgy, focusing on specific metals are insufficient to reach these goals. Instead, this paper discusses the emerging topic of direct recycling, which recovers, regenerates, and reuses the main battery components: electrolyte, negative and positive electrodes to create new LIBs. Although this approach may add complexities to the process, it significantly increases recovery rates, prevents component destruction and minimizes losses. This critical review synthesizes ideas and methods to provide new perspectives on recycling the main components of LIB.