Direct reuse of aluminium and copper current collectors from spent lithium-ion batteries

Abstract

The ever-increasing number of spent lithium-ion batteries (LIBs) has presented a serious waste-management challenge. Aluminium and copper current collectors are important components in LIBs and take up a weight percentage of more than 15%. Direct reuse of current collectors can not only effectively reduce LIB waste and provide an alternative renewable source of aluminium and copper, but also prevent long manufacturing processes and energy input for new current collectors. However, work on the direct reuse of current collectors is lacking in the literature. Herein, aluminium and copper current collectors are reclaimed from commercial spent LIBs with simple chemical treatments and we illustrate their successful reuse for LiNi0.6Mn0.2Co0.2O2 cathodes and graphite anodes, respectively. The reclaimed current collectors treated with different processes show different surface compositions and morphology to pristine ones, resulting in distinctive wettability, adhesion strength and electrical conductivity. The reused current collectors show similar electrochemical performance to the pristine one at low C rates, while extra caution should be taken at high C rates for aluminium current collectors due to relatively low contact conductivity. This work provides the first evidence that the direct reuse of aluminium and copper current collectors is possible and highlights the importance of the surface morphology of current collectors.