A SiOx-Based Anode in a High-Voltage Lithium-Ion Battery

A novel synthetic procedure for the preparation of a SiOx-based nanocomposite, involving gelification of resorcinol-formaldehyde and tetraethyl orthosilicate, is reported. The composite is characterized as an anode material in a lithium-ion battery. The micrometric, amorphous material has a characteristic nanostructured configuration and shows an electrochemical process involving both the alloying of Li−Si and the insertion of Li into the hard carbon matrix. The electrode reveals in a lithium half-cell a relatively low impedance and a reversible capacity ranging from 650 mAh g−1, at the lower current, to 400 mAh g−1 at high current regimes, with a cycle life extending to 200 cycles. The anode is combined with a high-voltage LiNi0.5Mn1.5O4 spinel cathode in a 4.3 V lithium-ion battery delivering a capacity of about 115 mAh g−1 and operating at the high rate of 5C. The suitable synthesis pathway, the low cost and the promising electrochemical behavior suggest the nanocomposite anode for application in high-performance lithium-ion battery.