Ultra-Sleek High Entropy Alloy Tights: Realizing Superior Cyclability for Anode-Free Battery.

The development of Li-free anodes to inhibit Li dendrite formation and provide high energy density Li batteries is highly applauded. However, the lithiophobic interphase and heterogeneous Li deposition hindered the practical application. In this work, a 20 nm ultra-sleek high entropy alloy (HEA, NiCdCuInZn) tights w ere developed by a thermodynamically driven phase transition method. Multiple Li + transport paths and abundant active sites are enabled by the cocktail effect of different constituent elements in HEA. These active sites with gradient absorption energies (-3.18∼-2.03 eV) facilitate selective binding, providing a low barrier for homogeneous Li nucleation. Simultaneously, multiple transport paths promote Li diffusion behavior with uniform Li deposition. Thus, the HEA/C achieves high reversibility of Li plating/stripping processes over 2000 cycles with a CE of 99.6% at 5 mA cm -2 /1 mAh cm -2 in asymmetric cells, as well as over 7200 h at 60 mA cm -2 /60 mAh cm -2 in symmetric cells. Moreover, the full cell with the HEA/C host without Li metal and a high-loading (17.6 mg cm -2 ) NCM-811 cathode has an average CE of 99.5% at 1 C after 160 cycles. This advanced HEA structure design shows a favorable potential application for anode-free Li metal batteries. This article is protected by copyright. All rights reserved.