A high-capacity and stable rate-performance Li-ion battery anode using hierarchical microcakes in-situ growing with nanoflakes

Designing high-performance anode materials is highly required and significant for developing next-generation Li-ion batteries since currently available graphite-based anode can hardly meet the need of advanced battery systems. Here, we develop a Fe2O3 microcake growing with Cu0.75Co2.25O4 nanoflakes, forming a hierarchically micro-nanostructured Fe2O3@Cu0.75Co2.25O4 composite, which exhibits high electrothermal performance as Liion battery anode material. Hierarchical structure effectively prevents the deterioration of cycling performance caused by large volume-change during cycling, while the nanoflakes growing on microcakes facilitate transport of ions and electrons. The results show that the Fe2O3@Cu0.75Co2.25O4 microcakes-based anode displays a high and stable capacity of 1029 mAh g⁻¹ after 100 cycles at 0.2 A g⁻¹, and stable rateperformance is also achievable. Moreover, in-situ X-ray diffraction study indicates reversible phase conversion upon charge-discharge. Our findings provide a promising design of hierarchical microcake structure for developing high-performance energy-storage composites and their secondary batteries.