Growth Mechanism of Lithium Clusters on the Surface of Porous Carbon Framework for Lithium Metal Batteries

Carbon-based frameworks as a metallic lithium (Li) host have been widely developed to overcome the drawbacks associated with bare Li metal anode. Achieving a complete understanding of the growth mechanism of the Li clusters in the carbon host remains controversial, however, and requires determining the factors involved and their clear causes. Herein, we have carried out density functional theory calculations to predict the growth mechanism of Li clusters by employing different heteroatoms (pyridinic N, pyrrolic N, quaternary N, and Co-N4). As a key feature, the Co-N4 affects the Li deposition behavior with axial Li growth on the surfaces of the carbon frameworks, while the other heteroatoms (i.e., nitrogen defects) induce vertical Li growth. By combining theoretical calculations and experiments, this detailed investigation widens the scope of future research on carbon host materials for practical usage of Li metal batteries.