Li4Ti5O12/AC非对称电化学电容器的研究

应用纳米微晶TiO2为原料,通过高温固相反应合成了具有尖晶石结构的锂钛复合氧化物Li4Ti5O12,该材料的首次嵌脱锂效率可达91.9%,10 mA/g电流密度下的可逆嵌锂容量为102 mAh/g。将其制成嵌锂电极后与活性炭电极构成新型的Li4Ti5O12/AC非对称电容体系。测试结果表明:在80 mA/g条件下,其双电极比电容为41.6 F/g,能量密度为采用相同电解液体系的AC/AC双电层电容的4.6倍,充放电效率达95.8%,且大电流性能及循环性能良好。

Study on Li4Ti5O12/AC asymmetric electrochemical capacitors

Li4Ti5O12 prepared from nanocrystalline titanium dioxide showed a good lithiation performance. The reversible capacity of the material was more than 102 mAh/g at a 10 mA/g current density, the first charge-discharge efficiency was 91.9 %. Then, the Li4Ti5O12/AC asymmetric capacitors using Li4Ti5O12 as the anode and activated carbon as the cathode were assembled. The results show that its bio-electrode specific capacitance is 41.6 Fig at a current density 80 mA/g,, its energy density is 4.6 times of that of the electric double-layer capacitors compared with AC/AC electric double-layer capacitor in the same type electrolyte. The charge-discharge efficiency of the asymmetric system could reach to 95.8 % and its high power and cycle performance are all good.