Vacancy-clusters in-situ induced via microwave-irradiation enable high-durability and capacitor-level rate li-ion storage

Abstract

The minutes-level charging capability is an actually-inevitable result of the contemporary battery industry, which thus demands the highly-effective battery electrodes with excellent electrode kinetics. Here, we newly-design the novel electrode nanomaterials via a rapid microwave-hydrothermal method to in-situ grown the oxygen-vacancy Li4Ti5O12 (LTO) nanoclusters on the functionalized carbon nanotubes (FCNTs). Density functional theory (DFT) studies discover that the enriched vacancies indeed tune the electron localization at atom-level, which then well-influences the corresponding state of densities, resulting in the superior electron conductivity and high Li+ affinity. In addition, the nano-level vacancy-clusters, groupings of vacancy-LTO nanoparticles, provide a strong in-built electric-field micro-environment. Combined with highly-effective electron highway of FCNTs, the resultant electrode delivers a remarkable capacitor-level rate-ability (store ∼ 55.5% of the theoretical capacity only within 2 min) and long-lived durability (2000 cycles at 2C with an ultralow decay rate of 0.003% per cycle). Furthermore, we have respectively developed pouch-type and fiber-shape full-battery based on above LTO-based anode, both of which have high mechanical properties and stable capacity delivery. This study provides promising prospects for LTO-based materials in fast-charging and flexible batteries.