One-pot synthesis of MnO-loaded mildly expanded graphite composites as high-performance lithium-ion battery anode materials

Improving the properties of conventional graphite anode materials has been an important research topic for enhancing the performances of lithium-ion batteries (LIBs). Herein, we develop a facile one-pot approach to mildly expand graphite (MEG) and simultaneously load MnO onto the as-prepared MEG to synthesize MnO@MEG composites as high-performance anode materials for LIBs. With the improved porous structure and electrical conduction network, both the MEG and MnO components of the composite exhibit well-defined electrochemical properties and alleviated volume changes upon charge/discharge, synergistically enhancing the electrochemical performances for our composites. With a high active material content and high mass loading for the testing electrode, the optimized MnO@MEG composite shows a high capacity (437.77 mAh g−1 at 0.1 C), a high rate capability (capacity retains 71.93% at 1 C vs. 0.1 C), and a high cycling stability (capacity retains 73.17% and 68.13% after charge/discharge at 0.5 C and 1 C, respectively, for 50 cycles), significantly outperforming its pristine graphite counterpart and previously reported similar MnO composites with other carbon materials, thereby standing for a practically promising anode material for LIBs. Broadly, the one-pot approach developed in the present work can be extended for producing other graphite-based composites for other energy-related technologies. •A facile one-pot approach is developed to process graphite into MnO@MEG composites as anode materials for LIBs.•The expansion of MEG and loading of MnO of the composites can be simultaneously accomplished in a controllable manner.•Well-defined electrochemical properties of MEG and MnO enhance the electrochemical performances of the composites.•Significantly enhanced performances of the composites make them practically promising for high-performance LIBs.•Our one-pot approach can be extended to produce composites for other energy-related technologies beyond LIBs.