Fig. 4: Application and performance of an Al-anode lithium battery.

a Structure of an Al-anode Li-ion battery compared with a conventional Li-ion battery. The Cu anode current collector is not needed when using the Al anode. The as-rolled Al anode can be assembled directly. b Electrode reaction of an Al anode. Al matrix is partly lithiated during pre-charge and the lithiated layer forms columnar-porous structure in discharge and works as the active materials in further cycles. c Cycle performance of a lithium battery consisting of an Al anode and a LiCoO₂ cathode. The inset SEM image shows the surface of the Al anode after 120 cycles. Electrode properties at initial cycles is shown in Supplementary Fig. 2e. d Potential profiles of cycle 10, 40, 70,100 and 120 in the cycle tests. No obvious degradation is observed on the Al anode. e Surfaces and cross-sections of Al anodes after initial lithiation of 2 mAh cm⁻² and after subsequent 10th lithiation. The active layer and current-collector layer are well-retained without consuming. Scale bars in SEM images are 100 μm.