Established recycling methods for lithium-ion batteries are highly energy-intensive or chemical-consuming, therefore, a new electrochemistry-based recycling method was developed aiming to overcome these challenges. Leaching of cathode materials (LCO and NCM) in sulfuric acid is performed without an addition of further chemicals (e. g. hydrogen peroxide). Instead, the in-situ electrogeneration of peroxydisulfate on a boron doped diamond electrode from sulfuric acid is utilized to enhance the reactivity of the solution and therefore increase the leaching rates of the cathode materials LCO and NCM.

Leaching prestudies, with LCO powder and peroxydisulfate added as salt, were performed to obtain the ideal leaching parameters (5 M sulfuric acid, 5 g·L-1 at 65 °C). At ambient temperature, the cobalt conversion rate will be limited to 40%. The use of 5 M sulfuric acid and elevated temperature with added peroxysulfate will increase the conversion rates of cobalt and lithium significantly. These ideal parameters have been applied to the electrochemical system to obtain similar or even better leaching results with high extraction rates for Li, Co, Ni, Mn without the need for other leaching reagents. The use of renewable electricity as the major energy input can make the process economically and ecologically more sustainable compared to other methods.