Safe management and effective resource circulation of lithium secondary batteries after use in electric vehicles

Abstract

A rechargeable (secondary) battery is a battery which can be repeatedly charged by converting the external electric energy into a form of chemical one. Today, the lithium secondary battery has been widely used in mobile phone, Electric Vehicle (EV), Energy Storage System (ESS), etc. However, the collection and waste management system for disposed lithium batteries has not been established properly. Since the Extended Producer Responsibility (EPR) regulation only targets batteries made of mercury, silver-oxide, lithium primary, nickel-cadmium, manganese/ alkaline-manganese, and nickel-hydride, lithium secondary batteries have been untouched for waste management. In particular, the disposed lithium secondary batteries for electric vehicles (waste EV batteries) which are subject to government subsidies are required to be returned to local governments under 「Clean Air Conservation Act」. However, a proper management system has not been developed thereafter. A careful treatment and transportation system is required for waste EV batteries due to their high risk of explosion. In addition, prices for valuable metals in ithium secondary battery packs are currently rising rapidly due to the increased demand for them. Cobalt and lithium, considered as valuable metals, are the core components of cathode active materials that account for 40% of material costs for a lithium-ion battery pack. Considering the risk of explosion and the trend of increasing price of valuable metals (cobalt, nickel, lithium, etc.) used in the lithium secondary batteries, it is necessary to build the safe management and effective resource circulation system of waste EV batteries. Therefore, we conducted the secondary material flow analysis for the waste EV batteries. With the analysis, we found out waste management issues of EV batteries and suggested applicable improvement measures for recycling the waste batteries. Finally, we estimated the effect of import substitution by recovering the valuable metals.