Electrochemical performance of all-solid-state lithium secondary batteries with Li-Ni-Co-Mn oxide positive electrodes

LiNi1/3Co1/3Mn1/3O2 was applied as a promising material to the all-solid-state lithium cells using the 80Li(2)S 19P(2)S(5) 1P(2)O(5) (mol%) solid electrolyte The cell showed the first discharge capacity of 115 mAh g(-1) at the current density of 0 064 mA cm(-2) and retained the reversible capacity of 110 mAh g(-1) after 10 cycles The interfacial resistance was observed in the impedance spectrum of the all-solid-state cell charged to 4 4V (vs Li) and the transition metal elements were detected on the solid electrolyte in the vicinity of LiNi1/3Co1/3Mn1/3O2 by the TEM observations with EDX analyses The electrochemical performance was improved by the coating of LiNi1/3Co1/3Mn1/3O2 particles with Li4Ti5O12 film The interfacial resistance was decreased and the discharge capacity was increased from 63 to 83 mAh g(-1) at 1 3 mA cm(-2) by the coating The electrochemical performance of LiNi1/3Co1/3Mn1/3O2 was compared with that of LiCoO2 LiMn2O4 and LiNiO2 in the all-solid-state cells The rate capability of LiNi1/3Co1/3Mn1/3O2 was lower than that of LiCoO2 However the reversible capacity of LiNi1/3Co1/3Mn1/3O2 at 0 064 mA cm(-2) was larger than that of LiCoO2 LiMn2O4 and LiNiO2 (C) 2010 Elsevier Ltd All rights reserved