A Facile Carbon Coating on Mg-Embedded SiOx Alloy for Fabrication of High-Energy Lithium-Ion Batteries

The use of SiOx-containing anode materials to increase the energy density limited by the utilization of low gravimetric specific capacity commercial graphite has recently received great interest. However, a low initial Coulombic efficiency and other inherent disadvantages of SiOx such as huge volume changes and poor electron transportation result in complicating its widespread use. To overcome these issues herein, a simple, cost-effective, and mass-producible phenolic resin-coated Mg-SiOx anode composite for high-performance lithium-ion batteries compared to the carbon film produced by the chemical vapor deposition method is designed. Carbon-coated Mg-SiOx based on the phenolic resin is found to act as a direct contact protection electrolyte-electrode interface and boosts kinetics of Li+ transport among the electrodes, ensuring the formation of stable solid electrolyte interphase upon cycling. As a result, the phenolic resin-coated Mg-SiOx alloy electrode delivers a stable specific capacity up to approximate to 1700 mAh g(-1) after 100 cycles. Testing with an industrial protocol, a full cell pairing of the Mg-SiOx@C/graphite blended anode and commercial LiNi0.8Mn0.1Co0.1O2 cathode achieves a gravimetric and volumetric energy density of 467 Wh Kg(-1) and 953 Wh L-1, respectively, which is higher than that of the cell based on the conventional graphite.