Unveiling the passivation and corrosion process of cathode aluminum current collector in lithium-ion battery

To ensure reliable deployment of stable high-voltage LIBs, investigating the corrosion behavior and underlying mechanism of the Al current collector is imperative. This research on Al corrosion in LiPF6 electrolyte indicates that the stability of the passivation layer (AlF3/Al2O3) is significantly affected by the operating voltage. The corrosion resistance, Rpit, displays a nonlinear distribution with a peak at 4 V, and pitting occurs beyond 4 V. The heterogeneous and wrinkled AlF3 layer triggers localized breakdown. The established model of pitting initiation and expansion is supported by morphological evolution, quantitative component analysis, and electrochemical test results.