Supplement Number 1

The supplementary material contains the following: the configuration of stage-1, 2, 3, 4, and 5 AlN structure, the AIMD structures at "t=0 ps", " t=10 ps ", and " t=20 ps ", the PDOS of individual clusters (stage-1 and stage-4) and individual AlN cathode materials (stage-1 and stage-4), the energy profiles of AlCl4 cluster along different pathways at the stage-1, 2, 3, and 4 (AlN-AlCl4) ICs, the distance between AlCl4 clusters and AlN cathode materials in stage-1, 2, 3, 4, and 5 (AlN-AlCl4) ICs, structural changes of AlCl4 cluster before and after AIMD simulations, charge transfer of stage-1, 2, 3, 4, and 5 (AlN-AlCl4) ICs with the insertion of a single cluster, and the diffusion lengths, the highest ground energies, and the diffusion barriers of AlCl4 cluster in the different stages (AlN-AlCl4) ICs.