Correlation between structural characteristics of edge selectively-oxidized graphite and electrochemical performances under fast charging condition

In the pursuit of ameliorating of the battery-performance degradation particularly during fast charging of lithium-ion batteries, we investigated the influence of surface-structural parameter of graphite. To explore the effect of the graphite surface state on the battery performance, we synthesized the edge selectively-oxidized graphite. The detailed analysis about the structural parameters of graphite samples revealed that the edge area increased from 3.41 to 4.26 m2 g−1 by oxidation process while preserving the specific surface area. Edge selectively-oxidized graphite samples showed the similar ratio between carbon and oxygen regardless of oxidized time, but the change of surface charge due to the different functional groups. The edge selectively-oxidized graphite exhibited a significantly improved capacity retention and rate performance compared with the bare graphite. Based on thorough examination about material properties and electrochemical responses, we corroborated a strong correlation among the electrochemical performance, edge surface area, and type of oxygen-based functional groups of graphite. Our study provides conclusive evidence that the surface nature of graphite plays a pivotal role in boosting the battery performance.