Preparation of Li₄Ti₅O₁₂ with hydration titanium dioxide for electrochemical hybrid capacitor

A novel pseudo-nanocrystalline Li₄Ti₅O₁₂ spinel was prepared using hydration titanium dioxide as starting materials. Hydration titanium dioxide added with activated carbon, citric acid and lithium salt was heat-treated at 800°C in air for 12h after desiccation. The spinel shows a good lithiation performance. Its reversible capacity is more than 152.3 mAh/g at current density of 85 mA/g, the first charge-discharge efficiency is 99.3% and its charge-discharge potential is flat and steady. Then, the Li₄Ti₅O₁₂/AC hybrid capacitors using Li₄Ti₅O₁₂ as the anode and activated carbon as the cathode is assembled. Electrochemical tests show that at current density of 85 mA/g, the specific capacity of Li₄Ti₅O₁₂ electrode is 96.4 mAh/g and the efficiency of hybrid capacitor is 96.5%.