Hybrid anode materials for rechargeable batteries — A review of Sn/TiO2 based nanocomposites

Lithium-ion batteries (LIBs) have been used as energy storage devices for appliances of a wide range of sizes, for example, mobile phones, laptops, and electric vehicles. However, current commercial electrode materials in LIBs are facing severe challenges in energy density, safety, price, and recyclability, and this energy storage technology needs to be further developed for high power application in future. To address this challenge, nanostructured materials which possess large surface-to-volume ratios have been intensively studied as potential electrode materials to improve the battery performance. Among them, Tin (Sn) and nanostructured TiO2 have shown some advantages and disadvantages as electrode materials, for example Sn has high storage capacity but suffer from severe volume expansion during lithiation/delithiation. On the other hand, nanostructured TiO2 has small volume changes during Li ion insertion/extraction, but the poor ion mobility and electronic conductivity limited it electrochemical application. This review summarizes the recent development on Sn and TiO2 based nanostructure materials, particularly the synthesis method, their structure and battery performance as anodes for LIBs. Then, we discuss the strategies of developing new electrode materials and highlight a hybrid approach for designing and synthesizing high-performance electrode materials. The latest developments and related electrochemical performance of anode materials demonstrate that design hybrid nanostructure material is a low-cost and scalable approach to produce high-performance electrode materials for high-energy LIBs.