Li-ion batteries (LIBs) currently are the dominant power sources for portable appliances including mobile phones, notebook computersand so on. Transition-metal oxides (TMOs, here TM = Co, Fe, Ni, Cu, etc.) have demonstrated to be promising high-performance materials for the next generation of LIBs. Among the TMO materials, copper oxides such as CuO and Cu2O have attracted increased attention due to their superiorities in properties including a high theoretical capacity (670 mAh g？1 for CuO) and improved safety compared to graphite.

Researchers with Institute of Process Engineering (IPE) reported a comparative investigation on the electrochemical application of mesoporous copper oxide (Cu2O and CuO) microspheres with different surface areas as anode materials in Li-ion batteries.

In their work, mesoporous Cu2O microspheres with a narrow particle size distribution were synthesized by hydrothermal method and CuO was obtained by subsequent oxidation of Cu2O.

The synthesized mesoporous Cu2O and CuO microspheres with a diameter of 400–1000 nm possessed surface area of 12.7–65.8 and 5.2–37.6 m2 g？1 and average crystal size of 15.0–20.5 and 10.4–15.9 nm, respectively. The mesoporous Cu2O-1 and CuO-1 microspheres with higher surface area showed an initial charge capacity of 430.5 mAh g？1 and 601.6 mAh g？1 and delivered a capacity as high as 355.2 mAh g？1 and 569.8 mAh g？1 than the Cu2O and CuO microspheres with lower surface area after 50 cycles, respectively.

The charge–discharge experiments and CV revealed that the surface area played an important role in determining the electrochemical performance of mesoporous Cu2O and CuO microspheres, as the highly developed mesoporous structure can enhance the accommodation of lithium ions, shorten the diffusion distance for lithium ions, and increase the absorption of electrolyte.

This studyis hoped to be beneficial to the development of high capacity and long cycling life anode materials for the next generation of Li-ion cells.

The paper was published in Journal of Power Sources.