New Strategy of Electrochemical Precipitation to Metals Separation in Spent Ncm Cathode Materials for Direct Regeneration

Abstract

Recycling of spent lithium-ion batteries (LIBs) can save mineral resources and eliminate the environmental hazards. This work proposes a new strategy for an efficient and green separation of valuable metals in spent Li(Ni 1/3 Co 1/3 Mn 1/3 )O 2 (NCM) LIBs. Through one-step controllable electrochemical precipitation, the complete separation of Li from Ni, Co and Mn in the acidic leachate solution of spent NCM materials and the preparation of NCM precursor are achieved simultaneously without addition of any separation or precipitation agents. The OH - produced from electrolytic system itself combines with the Ni 2+ , Co 2+ and Mn 2+ in leachate to form the co-precipitates of M(OH) x (M=Ni, Co and Mn). The left Li-containing solution is evaporated to obtain LiOH. These two hydroxides can be used directly to regenerate new NCM cathode material with excellent electrochemical performances, which can be comparable to those of commercial NCM material. Compared with the traditional recycling technology, the electrochemical precipitation strategy significantly reduces steps of the recycling process.

Keywords: Electrochemical Separation, Metal precipitation, NCM Precursor, Regeneration, Spent LiNi1/3Co1/3Mn1/3O2 Battery