리튬이온전지 적용을 위한 전기방사 올리빈 파이버의 고율특성 향상에 관한 연구

Abstract

The storage of electrical energy at high charge and discharge rate is of great importance in recent technological applications ? e.g. hybrid and plug-in hybrid electric vehicles. Among the cathode materials for rechargeable lithium-ion battery, LiFePO4 is a promising candidate for the next generation of lithium-ion battery because of it`s cost - efficiency, safety, excellent cycle ability, and large charge-discharge capacity. However, LiFePO4 has several critical drawbacks in extremely low electronic conductivity and slow lithium ion diffusion rate across the LiFePO4 / FePO4 boundary due to its intrinsic character. Therefore here I am show a systematic investigation on the enhancement in rate capability at high rates of charge and discharge by fabricating carbon-coated LiFePO4 nanofibers. Using a sol-gel processing and electrospinning technique, ultra-thin poly vinyl pyrrolidone(Mw:130,0000) / lithium carbonate / iron oxalate dihydrate / diammonium phosphate composite nanofibers of were prepared. After calcinations of the above precursor fibers at 600?C, LiFePO4 nanofibers with a diameter of 80 ~ 120 nm, were successfully obtained. As-prepared materials were characterized in regard with crystal structure, morphology, chemical composition, electrochemical properties by various methods.