Synthesis of Copper Oxide/Graphite Composite for High‐Performance Rechargeable Battery Anode

Abstract

A novel copper oxide/graphite composite (GCuO) anode with high capacity and long cycle stability is proposed. A simple, one-step synthesis method is used to prepare the GCuO, through heat treatment of the Cu ion complex and pristine graphite. The gases generated during thermal decomposition of the Cu ion complex (H and CO ) induce interlayer expansion of the graphite planes, which assists effective ion intercalation. Copper oxide is formed simultaneously as a high-capacity anode material through thermal reduction of the Cu ion complex. Material analyses reveal the formation of Cu oxide nanoparticles and the expansion of the gaps between the graphite layers from 0.34 to 0.40 nm, which is enough to alleviate layer stress for reversible ion intercalation for Li or Na batteries. The GCuO cell exhibits excellent Li-ion battery half-cell performance, with a capacity of 532 mAh g at 0.2 C (C-rate) and capacity retention of 83 % after 250 cycles. Moreover, the LiFePO /GCuO full cell is fabricated to verify the high performance of GCuO in practical applications. This cell has a capacity of 70 mAh g and a coulombic efficiency of 99 %. The GCuO composite is therefore a promising candidate for use as an anode material in advanced Li- or Na-ion batteries.

Spray-Printed and Self-Assembled Honeycomb Electrodes of Silicon-Decorated Carbon Nanofibers for Li-Ion Batteries

“…In the 1st cycle, the very high discharge capacity of all electrodes was likely associated with side reactions, including SEI formation, which is typical of CNFs. , In subsequent cycles and at relatively low current density (40–2000 mA/g), the electrodes had almost identical discharge capacities, implying little benefit of the micron-scale pores since there was sufficient time for ion transport to all active sites in both electrodes. However, a difference in deliverable capacity developed on further increase in the current density (≥4000 mA/g), with the honeycomb electrode delivering ∼100 mAh/g at 8000 mA/g that was three times that of the identical electrode without the honeycomb structure, outperforming conventional graphite electrodes (anodes) at similar rates. − Thus, despite the initial high reactivity and relative low electrode density, the honeycomb structure delivered significant benefits in the high C-rate region.…”

Influence of Ga2O3, CuGa2O4 and Cu4O3 phases on the sodium-ion storage behaviour of CuO and its gallium composites

“… 27 Sanghun et al proposed a novel single step synthesis method for copper oxide/graphite composite materials that were used as anode materials for rechargeable batteries, in which the interlayer distance of graphite was elevated to a higher value, resulting in high capacity and long-term cycling stability. 33 Another major problem associated with metal oxide anode materials is volume expansion and structure collapse, which eventually worsens the cycling stability and capacity. Huggins and Besenhard experimented on the usage of alloyed metal oxides for the first time and succeeded in making them better anode materials for energy storage devices.…”