LiNi1/3Co1/3Mn1/3O2 was redesigned into new core-shelled Li{[NiyCo1-2yMny]((1-x))}(core){[Ni1/2Mn1/2](x)}(shell)O-2 (0 <= x <= 0.3, 6y+3x-6xy=2) to improve its performances. Those core-shelled materials were successfully synthesized at 800 degrees C from core-shelled {[NiyCo1-2yMny]((1-x))}(core){[Ni-1/2 Mn-1/2](x)}(shell)(OH)(2) precursors obtained via a co-precipitation route. Scanning Electron Microscope (SEM) shows that a morphology with good spherical secondary particles developed from needle-like primary particles was formed in the precursors and maintained well in the lithiated compounds even after the calcination at 800 degrees C. Energy Disperse X-ray Spectrum (EDS) on the surface of precursors particles, in combination with evidence of size increase from core to shell during co-precipitation process, supports the formation of the core-shell structure as designed in the precursors. This is certified by subsequent EDS experiments on the cross-section of single particle of the lithiated compounds, showing that the lithiated compounds approximately had a targeted core-shell structure of Li{[NiyCo1-2yMny]((1-x))}(core){[Ni1/2Mn1/2](x)}(shell)O-2. Nevertheless, it is hard to detect differences in XRD for those lithiated compounds. Electrochemical tests and Differential Scanning Calorimetry (DSC) experiments demonstrate the gradually improved cyclability at a severe charge-discharge condition (55 degrees C and charging to 4.5 V) and thermal stability of materials with increasing x value (thickness of shell). (C) 2014 Elsevier Ltd. All rights reserved.