Direct Reuse of Aluminium and Copper Current Collectors from Spent Lithium-ion Batteries

TL;DR

This study demonstrates that aluminium and copper current collectors from spent lithium-ion batteries can be directly reclaimed and reused with comparable electrochemical performance, offering a sustainable waste management solution.

Contribution

It provides the first comprehensive analysis of direct reuse methods for current collectors from spent LIBs, highlighting surface morphology's role in performance.

Findings

Reclaimed collectors show similar low C rate performance to pristine ones.

Surface treatments affect wettability, adhesion, and conductivity.

High C rate aluminium collectors require careful handling due to lower contact conductivity.

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 effectively reduce LIB waste and provide an alternative renewable source of aluminium and copper. Besides, it also prevents long manufacturing processes and associated energy input and material consumption. However, there is a lack of work on the direct reuse of current collectors in the literature. Herein, aluminium and copper current collectors are reclaimed from commercial spent LIBs with different chemical treatments and successfully reused 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 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 substantial evidence that the direct reuse of aluminium and copper current collectors is possible and highlights the importance of the surface morphology of current collectors.