Coexistence of Lithium Metal and Graphite in Anode System for High-Energy Lithium-Ion Batteries

Lithium metal (LM) is a promising anode material for achieving high-energy density owing to its low electrochemical potential and high theoretical capacity. However, LM faces considerable challenges, such as volume expansion and dendrite formation, which induce critical degradation and safety concerns. Recently, the use of both LM and graphite in anode systems is employed as a strategy to mitigate these problems. In this review, electrodes containing both Li and graphite are categorized into three types based on their dominant Li storage mechanism during cycling, with strategies for each type are discussed. Additionally, the importance of the full-cell parameters necessary to achieve optimal performance with mixed lithium and graphite anodes is discussed. An enhanced understanding of the mechanism of the mixed anode system with lithium and graphite, with a detailed presentation of full-cell parameters, is of significant benefit for the academic and industrial use of lithium-ion batteries.