水合氧化钛制备Li_4Ti_5O_(12)及在电化学混合电容器中的应用

Preparation of Li_4Ti_5O_(12) with Hydration Titanium Dioxide for Electrochemical Hybrid Capacitor

以水合氧化钛溶胶为起始反应物,在其中加入活性炭、柠檬酸和锂盐,干燥后在800℃热处理12h,制得具有尖晶石结构的新型准纳米晶Li4Ti5O12.电化学测试表明,该材料的首次嵌脱锂效率可达99.3%,85mA/g电流条件下的可逆嵌锂容量为152.3mAh/g,嵌脱锂平台稳定.将其制成嵌锂电极后与活性炭电极构成Li4Ti5O12/AC电化学混合电容器.充放电测试表明,在该混合电容器中,Li4Ti5O12电极在85mA/g电流条件的比电容量为96.4mAh/g,电容器充放电效率达96.5%.

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℃ in air for 12h after desiccation. The spinel shows a good lithiation performance. Its reversible capacity is more than 152.3mAh/g at current density of 85mA/g, the first charge-discharge efficiency is 99.3 % and its charge-discharge potential is fiat and steady. Then, the LiaTi5 O12/AC hybrid capacitors using Li4Ti5O12 as the anode and activated carbon as the cathode is assembled. Electrochemical tests show that at current density of 85mA/g, the specific capacity of Li4Ti5O12 electrode is 96.4mAh/g and the efficiency of hybrid capacitor is 96.5%.