A successive "conversion-deposition" mechanism achieved by micro-crystalline Cu2O modified current collector for composite lithium anode

Lithium (Li) metal is a promising material for high-energy-density batteries, but it is still plagued by obvious capacity degradation and low average Coulombic efficiency resulting from dendrite Li propaga-tion. One main reason is the electro-mechanic coupled failure of plated Li on the current collector, which contributes to non-dense Li deposition on the anode. Transition metal oxides (TMOs) with a conversion -type mechanism have been used directly as the anode materials for lithium ion batteries, which demon-strated better electro-mechanical stability than metal Li. Herein, a successive "conversion-deposition"mechanism is ingeniously developed to restrain the generation of dendritic Li. Specifically, a micro -crystalline Cu2O modified current collector was prepared, in which Li+ are sequentially inserted into Cu2O and deposited in the form of Li metal at successive low potential. A Li-Cu half-cell based on the hybrid mechanism sustains a high Coulombic efficiency of over 99.3 % in up to 800 cycles. This work inge-niously inhibits the generation of dendrite Li by incorporating conversion-type materials with deposition-dissolution type metal Li, which contributes to a novel concept for the design of functional current collectors for composite Li anodes.(c) 2022 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.