喷墨打印制备LiMn2O4薄膜电极及其电化学性能

Electrochemical Performance of LiMn_2O_4 Thin Film Electrode Fabricated by Ink-Jet Printing Technique

通过溶胶-凝胶法制备了尖晶石LiMn2O4.用分散剂LormarD,经超声分散制得了含LiMn2O4粒子的打印"墨水",并使用计算机喷墨打印的方法制得LiMn2O4薄膜电极.薄膜电极的厚度约为1.8μm.用XRD、TG-DTA、SEM、循环伏安、电化学阻抗谱和充放电等方法对材料和电极的性能进行了表征.结果表明,在较大电流100μA·cm-2(2C)的充放电情况下,电极能保持好的稳定性,其首次放电容量为109mAh·g-1,充放电54次后,其容量仍可保持97.4%,为105mAh·g-1,这可归因于薄膜电极中尖晶石LiMn2O4的晶型完整,LiMn2O4粒子小以及稳定的超薄电极结构.

Under ultrasonic and using the additive Lomar D as dispersant, the printing ＂ink＂ can be prepared with LiMn2O4, which was synthesized through a sol-gel method. Through an ink-jet printing process, thin film LiMn2O4 electrode with thickness of about 1.8 μm was fabricated successfully. XRD, TG-DTA, SEM, electrochemical impedance spectrum, CV, and charge/discharge tests were used to characterize the LiMn2O4 nano particles and LiMn2O4 thin film electrode. It was found that LiMn2O4 film electrode could be charge-discharged at relative high current rate and kept stable. At the current density of 100 μA· cm^-2 （2C）, the thin film LiMn2O4 electrode had an initial capacity of 109 mAh·g^-1, after 54 cycles the discharge capacity remained 97.4%, as a value of 105 mAh·g^-1. This good electrochemical behavior of LiMn2O4 thin film electrode was mainly due to the thin thickness of electrode and well-crystallized LiMn2O4 nano particles.