논문 해외 국제전문학술지(SCI급) Structurally stabilized olivine lithium phosphate cathodes with enhanced electrochemical properties through Fe doping
- 학술지 구분 국제전문학술지(SCI급)
- 게재년월 2011-12
- 저자명 오민욱
- 학술지명 ENERGY & ENVIRONMENTAL SCIENCE
- 발행처명 RSC
- 발행국가 해외
- 논문언어 외국어
- 전체저자수 9
홈페이지논문 초록 (Abstract)
Controlling the crystallographic structure in olivine lithium phosphates is crucial for obtaining superior electronic (J. Electrochem. Soc., 2002, 149, A1184-A1189) and ionic conductivities (Electrochem. Solid-State Lett., 2006, 9, A352-A355; Electrochem. Solid-State Lett., 2006, 9, A439-A442; Nat. Mater., 2002, 1, 123-128), and stability, for use as cathodes in lithium batteries. Here, we report a completely new approach to enhance Li(+) extraction and transport in LiCoPO(4) through Fe doping. We show that preferential Fe occupation of the 4c sites suppresses 4a-4c antisite mixing of Li and Co, thereby stabilizing the olivine structure by compensating for the Co-encapsulating oxygen octahedron shrinkage due to Co(2+) oxidation during Li(+) extraction. The structural stabilization gives rise to similar to 10% higher charge capacity at a two-fold lower resistance than the undoped counterparts besides accelerating the intercalation/extraction kinetics. Our findings provide key atomistic-level insights that pave the way for the rational design and realization of new types of metal-doped cathode materials for lithium batteries and related applications.