Characterization on the electrochemical and structural properties of polyanion cathode material Li2MnSiO4/C depending on the synthesis process

Abstract ―Li 2 MnSiO 4 /C was synthesized by solid state reaction and solution synthesis with sucrose for carbon source. The X-ray diffraction patterns of solid state reaction indicates small amount of impurities. By FE-SEM and HR-TEM, solution synthesis comprised several tens of nanometer comparing to 500~600 nm of Li 2 MnSiO 4 /C prepared by solid state reaction. The Li 2 MnSiO 4 /C prepared by solution synthesis show better electrochemical performance than solid state reaction. The first charge-discharge capacity are 236, 189 mAh/g respectively by solution synthesis. But its cycle performance was poor as yet and its capacity retention was 62% after 10 cycles. Key words : Lithium manganese silicate, Lithium-ion battery, cathode, solid state reaction, solution synthesis 1. 서 론 모바일 통신 및 장비의 발달에 따라 전원 공급원인 리튬이차전지의 수요가 증가하고 있고 플러그인 하이브리드 자동차(Plug-in hybrid electric vehicles; PHEV), 전기자동차(Electric vehicles; EV)와 대용량 전기저장 장치(Electric energy storage)의 발달은 대용량 리튬이차전지의 개발을 필요로 한다 . 하지만 현재 사용되고 있는 양극 활물질은 LiCoO