Highly porous reticular tin–cobalt oxide composite thin film anodes for lithium ion batteries

Abstract

A tin-cobalt oxide film with a 3-dimensional (3D) reticular structure has been prepared by electrostatic spray deposition (ESD). X-Ray diffraction (XRD) and transmission electron microscopy (TEM) make it clear that the film is amorphous. X-Ray photoemission spectroscopy (XPS) indicates that the 3D grid is composed of SnO 2 and CoO. As an anode for the lithium ion battery, the film has 1240.2 mAh/g of initial discharge capacity, shows a gradually increasing capacity after the first cycle, and has 845 mAh/g of discharge capacity up to the 50 th cycle. The high porosity of the 3D reticular structure can provide more reaction sites on the electrode surface and accommodate volume variation of Sn particles during Li alloying-dealloying. The CoO in the complex composite film plays an important role, allowing the formation of a polymeric gel-like film to improve its electrochemical performance, preventing Sn aggregation during charging and discharging. Such a composite film can be used as an anode for lithium ion batteries with higher energy densities.

Rational design of metal oxide nanocomposite anodes for advanced lithium ion batteries

“…Moreover, due to the difference of the electrochemical reaction potential between SnO 2 and Fe 2 O 3 (Fig. 4b), when one component is electrochemically engaged, the other acts as the buffer matrix to prevent the former aggregating and crack formation subsequently [14,15]. In addition, the generated Fe nanoparticles enhance the electrical conductivity and benefit for the high rate performance [50].…”

Nanostructured hybrid cobalt oxide/copper electrodes of lithium-ion batteries with reversible high-rate capabilities

“…In contrast, the planar CoO/Cu electrode delivers initial discharge and charge capacities of 1416 mAh g −1 and 772 mAh g −1 , respectively, indicating that it has an initial Coulombic efficiency of 54.5%, which is much lower than that of the nanostructured electrode. The irreversible capacity loss of the CoO/Cu electrodes is mainly due to the formation of the solid-electrolyte interphase (SEI) layer and partial irreversible electrochemical reactions during further cycling because of the Co aggregation [25]. Compared to the planar electrode, the nanostructured CoO/Cu electrode could improve the electronic/ionic conductivity of the CoO/Co 0 /Li 2 O matrix and prevent Co particles from aggregating somehow, resulting in an improved initial Coulombic efficiency.…”

Anodes for Li-Ion Batteries

“…They delivered a reversible capacity of 446 mAh g À1 after 50 cycles at the 100 mAh g À1 rate and excellent rate capability of 477.7 mAh g À1 at 10C rate. In the form of thin films, the best results have been obtained with Sn-Co-O and Sn-Mn-O films [442,443]. In particular, at C/2 rate, the Sn-Co-O films delivered a reversible capacity of 734 mAh g À1 .…”