title: Influence of Ti(4+) on the electrochemical performance of Li-rich layered oxides - high power and long cycle life of Li2Ru1-xTixO3 cathodes.
abstract: Li-rich layered oxides are the most attractive cathodes for lithium-ion batteries due to their high capacity (>250 mAh g(-1)). However, their application in electric vehicles is hampered by low power density and poor cycle life. To address these, layered Li2Ru0.75Ti0.25O3 (LRTO) was synthesized and the influence of electroinactive Ti(4+) on the electrochemical performance of Li2RuO3 was investigated. LRTO exhibited a reversible capacity of 240 mAh g(-1) under 14.3 mA g(-1) with 0.11 mol of Li loss after 100 cycles compared to 0.22 mol of Li for Li2Ru0.75Sn0.25O3. More Li(+) can be extracted from LRTO (0.96 mol of Li) even after 250 cycles at 143 mA g(-1) than Li2RuO3 (0.79 mol of Li). High reversible Li extraction and long cycle life were attributed to structural stability of the LiM2 layer in the presence of Ti(4+), facilitating the lithium diffusion kinetics. The versatility of the Li2MO3 structure may initiate exploration of Ti-based Li-rich layered oxides for vehicular applications.
authors.affiliation: †School of Materials Science and Engineering, Chonnam National University, 300 Yongbong-dong, Buk-gu, Gwangju, 500-757, Republic of Korea.
authors.forename: Abdul Kareem
authors.initials: AK
authors.lastname: Kalathil
authors.affiliation: †School of Materials Science and Engineering, Chonnam National University, 300 Yongbong-dong, Buk-gu, Gwangju, 500-757, Republic of Korea.
authors.forename: Paulraj
authors.initials: P
authors.lastname: Arunkumar
authors.forename: Da Hye
authors.initials: DH
authors.lastname: Kim
authors.affiliation: §New and Renewable Energy Research Division, Korea Institute of Energy Research, Daejeon, 305-343, Republic of Korea.
authors.forename: Jong-Won
authors.initials: JW
authors.lastname: Lee
authors.affiliation: †School of Materials Science and Engineering, Chonnam National University, 300 Yongbong-dong, Buk-gu, Gwangju, 500-757, Republic of Korea.
authors.forename: Won Bin
authors.initials: WB
authors.lastname: Im
keywords: Li-rich layered oxides; Li2RuO3; and power density; cathodes; cycle life