Surface amorphous coating for an economical and high-stability current collector for rechargeable aluminum-ion...

Rechargeable aluminum-ion batteries (AIBs) are regarded as the next-generation energy storage devices due to their low flammability, low cost and high power density as well as abundant aluminum (Al) reserves. However, these popular ionic liquid electrolytes contain highly corrosive acid, which always corrodes the most used positive current collector, thus hindering the commercialization of AIBs. This study proposes an efficient and economical method of coating amorphous Ni₃S₂compound on a nickel metal current collector (Ni-S/Ni). The conductivity and the onset oxidation potential of amorphous Ni₃S₂coating can be up to 2.3 × 10⁶S m^-1and 2.7 V respectively. A Ni-S/Ni current collector can provide excellent cycling stability with no electrochemical corrosion in the AIBs. The AIBs fabricated using a Ni-S/Ni current collector exhibits a specific capacity of 65 mAh/g at 1 A g^-1, high coulombic efficiency of 99% and cyclability of at least 2000 cycles. Moreover, the total cost of the Ni-S/Ni current collector can be limited to less than 3.3 USD/m². The comprehensive performances of these AIBs are better than most reported results so far, which indicates that this method can advance the commercialization of AIBs.