Exfoliated few-layered graphite anode with broadened delithiation voltage plateau and fast charging performance for lithium-ion batteries
摘要
Graphite is the traditional anode material for lithium ion batteries (LIBs) owing to its excellent cycling performance and low delithiation voltage plateau. However, as for LIBs, the improvement of energy density is limited by the capacity below voltage plateau of graphite. Moreover, the enhancement of fast charging performance is also a major challenge for graphite anodes. Here, the few-layered graphite (FLG) is obtained from the supercritical CO2 exfoliation method. One of the primary advantages for FLG is that the voltage plateau is broadened evidently than those of pristine graphite (PG) and commercial graphite (CG), which enables FLG to possess higher energy density. Importantly, the enlarged interlayer spacing of FLG is beneficial to the migration of Li+, which promotes fast charging performance. Moreover, the full cell can provide an exceptional electrochemical performance (114 mAh g− 1 at 1 C after 200 cycles with a remarkable capacity retention of 84%). This special method can pave a new avenue to improve the energy density and fast charging performance of LIBs.