The art of Lithiation Revisited: Solvent-free room temperature reaction

The lithiation reaction holds immense significance across various branches of chemistry, particularly in the realm of electrochemical energy storage. Here, we report a new method that enables a solvent-free process at room temperature, exhibiting remarkably swift reaction kinetics. Through this process, the chemical integration of Li+ into charged materials based on transition metals is achieved using lithium iodide, LiI. An evident application of this method lies in advancing the direct recycling of cathode materials reclaimed from spent batteries. Notably, the process facilitates the efficient and direct recycling of spent Li(1-x)FePO4 cathode material, sourced from a commercial LIB, without the need for any solvents or heat treatments. The regenerated material exhibits a fully reversible capacity of approximately 168 mAh/g against Li metal, even under high current density conditions, with a consistently stable coulombic efficiency surpassing 99% over 45 cycles. This regenerative approach holds the potential for seamless extension to other LIB cathode materials, including but not limited to LMFP, LMO, LCO and NMC.