Preparation of an Li_0.7Ni_0.8Co_0.2O₂ Electrode Material From a New Li–Co–Ni Mixed‐Citrate Precursor

Abstract

A new chemical route to prepare the mixed oxide Li 0.7 Ni 0.8 -Co 0.2 O 2 , which is a member of the well-known Li-Ni-Co-O family that is of interest as an electrode material for rechargeable lithium batteries, from a mixed citrate is reported. In a first step the new citrate (NH 4 ) 3 LiNi 0.8 Co 0.2 (C 6 H 5 O 7 ) 2 , is synthesized, which, after thermal decomposition, gives the layered mixed-oxide phase Li 0.7 Ni 0.8 Co 0.2 O 2 . This oxide has been characterized by chemical analysis, XRD, FTIR, SEM, and DTA, revealing an "ideal" trigonal α-NaFeO 2 type struc-

Preparation and properties as positive electrodes of PANI–LiNi0.8Co0.2O2 nanocomposites

“…15 Of particular relevance are the ''nickel-rich'' oxides belonging to those systems 32,33 in which we have recently synthesized and characterized the Li x Ni 0.8 Co 0.2 O 2 mixed oxide. 34 This last solid is provided with good electrical and electrochemical behaviour, allowing its use as an efficient electrode in a Li/LiClO 4 (PC:EC)/(Li x Ni 0.8 Co 0.2 O 2 ) cell, in which the electrolyte is a standard 1 M LiClO 4 solution in a 1 : 1 polycarbonate : ethylene carbonate (PC : EC) mixture.…”

Materiais cerâmicos de inserção aplicados a baterias de íons lítio

“…8. 10, 14], e mais recentemente, os óxidos mistos e simples de metais de transição [2, 7-11, 14-20] e os compósitos [21][22][23][24][25][26][27][28][29].…”

Improvement of transport properties of Li x (Ni 0.8 Co 0.2 )O 2 oxide in the formation of Li x (Ni 0.8 Co 0.2 )O 2 /PANI composite

“…However, many authors have reported the presence of divalent nickel ions (r= 0.68 Å) at the lithium sites (r=0.74 Å) in the nickel rich phases. Recently we have proposed a chemical method that has allowed a dramatic change in the structural cationic ordering favoring the oxide a better behaviour as lithium battery cathode [4]. Another characteristic that present these oxides is their close crystalline structure and the completely occupation of lithium octahedral sites, so that way that when high current densities are used the grain surface polarization and loss capacity take place [3].…”

“…In this work we estimated the influence of the polymer in the transport properties of the composite through the calculation of the lithium diffusion coefficient for Li x (Ni 0. 8 [4,5]. X-ray diffraction patterns (XRD) were obtained on a Rigaku ultra -X 18BV2, with CuKα radiation ( 42 kV, 120 mA ) and scanned at a step scan rate of 0.02 o/s in 10-120 degree 2θ scan range.…”