Controllable synthesis of polystyrene microspheres used as template and in‐situ carbon source for Li 2 MnSiO 4 cathode material to boost lithium‐ion batteries performance

Abstract

Polyanion-type Li2MnSiO4 is considered to be a potential lithium storage material due to its high theoretical capacity, low cost, nontoxicity, and good thermal stability. Unfortunately, pure Li2MnSiO4 has poor conductivity and diffusion rate of Li+, which hinders its wide application in energy storage. In this study, Li2MnSiO4 with inverse opal structure is synthesized by simple sol–gel method, and monodisperse polystyrene microspheres (PS) with uniform and controllable size are prepared by soap-free emulsion. Additionally, Li2MnSiO4 material with a large specific surface area and mesoporous structure is synthesized by using PS as a template. Specifically, after adding 4 wt% of the PS template, the initial discharge specific capacity of the synthesized Li2MnSiO4 material is 109.9 mAh·g−1 at 0.1 C. Compared with pure Li2MnSiO4, the electrochemical performance of the material synthesized by this process has been significantly improved, which is attributed to the mesoporous structure and large specific surface area that improve the conductivity. Hence, the Li2MnSiO4 cathode material synthesized with PS as a template is expected to become an advanced positive material in lithium energy storage.