Guided dendrite-free lithium deposition through titanium nitride additive in Li metal batteries

摘要

Metallic lithium (Li) is one of the most potential anode materials in the near future, because of its high theoretical specific capacity (3865 mAh/g), low potential (-3.045 V vs standard hydrogen electrode (SHE)) and low density (0.534 g/cm(3)). However, fatal dendritic Li growth is the bottleneck of the development of Li anode. In this contribution, we reported a titanium nitride (TiN) nanoparticle additive to guide Li deposition uniformly, hence dead Li and dendritic Li are effectively reduced. There are more nucleation sites on the surface of the electrode due to the stronger adsorption of Li ions on each facet of TiN, and TiN nanoparticles play the role of seeds of Li deposition. The half cells cycling in additive electrolyte exhibit an average Coulombic efficiency (CE) of 97.19% for 270 cycles on plane copper (Cu) electrode and an excellent high average CE of 99.01% for 300 cycles on three-dimensional (3D) carbon paper (CP) electrode at 1 mA/cm(2) and 1 mAh/cm(2). Li-S full cells equipped with such TiN nanoparticles additive electrolyte deliver great enhanced cycling and rate performance. This work provides a new insight to suppress Li dendrite and realizing high performance of Li metal batteries. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.