Ag-modified hydrogen titanate nanowire arrays for stable lithium metal anode in a carbonate-based electrolyte

Abstract

Abstract In the investigation of the next-generation battery anode, Li metal has attracted increasing attention owing to its ultrahigh specific capacity and low reduction potential. However, its low columbic efficiency, limited cycling life, and serious safety hazards have hindered the practical application of rechargeable Li metal batteries. Although several strategies have been proposed to enhance the electrochemical performance of Li metal anodes, most are centered around ether-based electrolytes, which are volatile and do not provide a sufficiently large voltage window. Therefore, we aimed to attain stable Li deposition/stripping in a commercial carbonate-based electrolyte. Herein, we have successfully synthesized hydrogen titanate (HTO) nanowire arrays decorated with homogenous Ag nanoparticles (NPs) (Ag@HTO) via simple hydrothermal and silver mirror reactions. The 3D cross-linked array structure with Ag NPs provides preferable nucleation sites for uniform Li deposition, and most importantly, when assembled with the commercial LiNi0.5Co0.2Mn0.3O2 cathode material, the Ag@HTO could maintain a capacity retention ratio of 81.2% at 1 C after 200 cycles, however the pristine Ti foil failed to do so after only 60 cycles. Our research therefore reveals a new way of designing current collectors paired with commercial high voltage cathodes that can create high energy density Li metal batteries.