Ti3C2/CNTs Macroporous Conductive Network Boosts Li4Ti5O12-TiO2 Anode Performance for Practical Li Ion and Mg Ion Batteries

Abstract

Spinel lithium titanate (Li4Ti5O12) has been widely used as anode electrode for long-life lithium ion batteries (LIBs), however, it suffers from inherent poor electronic and ionic conductivity which limits its further development. Here, a composite macroporous conductive network is constructed by carbon nanotubes (CNTs) and few-layer titanium carbide (Ti3C2s) and used for the modification of Li4Ti5O12-TiO2. Owing to the excellent mechanical properties of CNTs and Ti3C2s, the prepared Ti3C2s-CNTs-Li4Ti5O12/TiO2 (T-C-L) material can be directly used as binder-free electrode. Specifically, CNTs serve as a connection skeleton to stabilize the electrode structure and provide a conductive network to improve electron transport capabilities; the addition of Ti3C2s is beneficial to the formation of macropores which can further improve ion diffusion; the existence of TiO2 phase can improve its capacity as well as rate capability. Reasonable design and the synergistic effect of each component endow T-C-L outstanding Li-storage performance and Mg-storage performance. When combined with lithium belt to form a pouch battery, the T-C-L also exhibits satisfactory bending performance, which further expand its practicality. These results show great promise of the prepared T-C-L for LIBs and magnesium ion batteries (MIBs) and provide a modification method for other electrode materials that suffer from poor ion/electron diffusion capabilities.