Facile and rapid Preparation of SiOx@cPPO-C particles for lithium-ion battery anodes by an oil phase diffusion method on pickering emulsions

Abstract

Silicon monoxide (SiOx) is an ideal candidate for lithium-ion battery (LIB) anode application. However, the Li⁺/e⁻ conductivity of SiOx is inferior and its volume expansion in charge/discharge cycles is huge, preventing the development of SiOx-based anodes. In this study, the carbonated polyphenylene oxide (PPO) is selected as the shell polymer to encapsule SiOx to obtain energy-storage microcapsules via a facile and efficient oil phase diffusion method on Pickering emulsions (OPDPE). After carbonization, the PPO (carbon precursor) as well as the carbon black (CB) construct the conductive shells for microcapsules (cPPO-C), enabling great Li⁺/e⁻ conductivity for anodes, and the hollow structure of capsules can provide sufficient buffer for the volume expansion of embedded SiOx particles. Compared with the pristine SiOx anode, the optimized SiOx@cPPO-C anode can exhibit improved electrochemical performances in terms of the rate capability, specific capacity, and capacity retention. Besides, the proposed OPDPE strategy can also present significant advantages, e.g., short operation time, simplified processing, and excellent technical adaptability, confirming its potential in large-scale preparation of Si-based LIB anodes.