Hierarchical Li4Ti5O12/C composite for lithium-ion batteries with enhanced rate performance

- The composite was prepared via one-pot way by utilizing glucose as carbon source.
- The obtained composite consists some grain-like particles pasted on the bulk LTO sheets.
- The composite possesses excellent cycle performance and high rate capacity

Considering the charming merits and natural defects of Li4Ti5O12 (LTO), we build a hierarchical LTO/C composite through a rational hydrothermal route by utilizing the low-cost glucose as carbon source. The obtained composite consists of some grain-like secondary particles (10-15 nm) pasted on the relatively bulk LTO sheets (50-100 nm). Due to the introduction of carbon, the composite has the smaller particle size, lower polarization and superior electrical conductivity. Besides, the as-prepared sample exhibits good cycling stability and outstanding rate performance. It delivers the discharge capacity of 174.1 mAh g−1 at 1C and left 131.7 mAh g−1 even at 50C, which is apparently superior than pristine LTO. Furthermore, the discharge capacity maintains 93.4% after 500 cycles at 1C and 80.5% after 1000 cycles at 50C. Even after 3000 ultralong cycles at 5C, the value still retains 74.2% which is much higher than that of pure LTO (38.4%). The ideal proportion of carbon modified in LTO is also explored. The LTO/C-3.74 wt% composite is demonstrated to possess optimal electrochemical performance.