Low-strain titanium-based oxide electrodes for electrochemical energy storage devices: design, modification, and application

To meet the growing demand for high-performance electrochemical energy storage devices, various kinds of anodes have been proposed, trying to substitute the traditional carbonous materials. Among them, low-strain Ti-based oxides (LSTBOs), especially Li4Ti5O12 and TiNb2O7, stand out for their remarkable safety and long cycling stability. Promising as they are for the high-power energy storage system, the restricted rate performance thereof owing to their poor electronic conductivity and discontented specific capacities nevertheless hinder their further commercial application. To broaden the utilization fields of LSTBOs electrodes, assorted works on the mechanism and tailing strategies have been extensively boosted to surmount these obstacles. Herein, we have summarized the latest advance and development of LSTBOs materials and application thereof in electrochemical energy storage including lithium-ion batteries, sodium-ion batteries, supercapacitors, and hybrid capacitors. At first, a brief introduction of the properties of LSTBOs is given to help reveal the reasons for existing demerits. Then, the melioration of LSTBOs themselves as well as LSTBOs devices are discussed, followed by the study of improvement mechanism of each strategy. In the end, we highlight the optimizing rules for developing advanced LSTBOs electrodes and hope that these bits of advice can serve as effective guidelines for future researches in realizing high power and high energy density devices.