Layered manganese oxide with O2 structure, Li(2/3)+x(Ni1/3Mn2/3)O2 as cathode for Li-ion batteries
2002; Elsevier BV; Volume: 4; Issue: 8 Linguagem: Inglês
10.1016/s1388-2481(02)00392-2
ISSN1873-1902
AutoresK. M. Shaju, G. V. Subba Rao, B. V. R. Chowdari,
Tópico(s)Dielectric properties of ceramics
ResumoUsing LiI as the reducing agent, the compound O2-Li(2/3)+x(Ni1/3Mn2/3)O2, x∼1/3 (O2(Li+x)) has been prepared from the O2-Li2/3(Ni1/3Mn2/3)O2 (O2(Li)). Cyclic voltammetry and voltage-capacity profiles of the O2(Li+x) phase are qualitatively different from that of O2(Li) phase. The first extraction capacity of O2(Li+x) at C/10 rate is 190 mAh/g corresponding to the removal of 2/3 mole of Li from the compound. At C/5 rate it delivers a reversible capacity of 158 mAh/g at 25 °C and 184 mAh/g at 50 °C (vs Li metal; voltage window 2.5–4.6 V). In Li-ion cells, with MCMB anode and O2(Li+x) as cathode, a discharge capacity of 140 mAh/g was obtained at C/5 rate in the voltage window 2.5–4.5 V (25 °C). The charge–discharge cycling performance and the cyclic voltammograms reveal that O2(Li) and O2(Li+x) do not convert to the spinel structure.
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