CF_x addition improves performance of batteries with Li₄Ti₅O₁₂ electrodes

Spinel Li₄Ti₅O₁₂ (LTO) has been considered as an anode for next generation lithium ion batteries. It has the advantages of negligible structural variation and high lithium intercalation plateaus. In addition, its negligible structural variation during lithium ion intercalation/deintercalation also provides a longer lifespan when applied as an anode. However, an inherently insulating property has currently limited its use in high-rate applications. Different from existing attempts, we demonstrate a facile method to improve the rate performance of Li₄Ti₅O₁₂ electrodes by introducing CF_x during the electrode preparation process. A series of Li₄Ti₅O₁₂ electrodes was fabricated with varied the additional ratio of CF_x that exhibited excellent rate performance even at a rate of 20 C. The best additive ratio was found to be 2.5% CF_x by mass, which produced electrodes with a reversible capacity of 164 and 102 mAh g⁻¹ at the rates of 1 and 20 C, respectively.