High entropy sulfides enable atomic-level interactions for high-performance rechargeable aluminum batteries

Rechargeable aluminum batteries (RABs) are promising in the energy storage fields owing to their high theoretical capacity, abundant resources, and high safety. However, the intrinsically high-charge-density of aluminum ions (Al 3+ , 364C mm −3 ), inevitably leads to large lattice strain and low electron transfer efficiency towards conventional cathodes, such as transition metal sulfides, with inferior performance. To overcome the inherent confinement, we first-timely propose the high-entropy sulfides (HESs) as the novel cathodes in RABs, exhibiting robust lattice tolerance and accelerated multi-path electron transfer. Benefiting from the interaction of multiple atoms and inherent long-range disorder in HESs, broadened atomic d-band ( ɛ d ) endows the local “electronic delocalization effect” with a high rate-capacity (above 193.0 mAh g −1 at 5.0 A g −1 ). Moreover, the well-constructed cathode forms a strong lattice strain field, providing one of the best long-term stabilities (0.004 % per cycle capacity decay over 12,000 cycles at a high current density of 5.0 A g −1 ) in RABs. Overall, the newly developed HESs with lattice distortion and cocktail effect endowing tunable electronic structures pave the new direction for RABs and other multivalent ion batteries.