Details

Autor(en) / Beteiligte

• HANSAN LIU
• JIE LI
• ZHONGRU ZHANG
• GONG, Zhengliang
• YONG YANG

Titel

Structural, electrochemical and thermal properties of LiNi0.8-yTiyCo0.2O2 as cathode materials for lithium ion battery

Ist Teil von

• Electrochimica acta, 2004-03, Vol.49 (7), p.1151-1159

Ort / Verlag

Oxford: Elsevier

Erscheinungsjahr

2004

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Multiple substitution compounds with the formula LiNi0.8-yTiyCo0.2O2 (0 # < y # < 0.1) were synthesized by so]-gel method using citric acid as a chelating agent. The effects of titanium substitution on the structural, electrochemical and thermal properties of the cathode materials are investigated. A solid solution phase (R-3m) is observed in the range of 0 # < y # < 0.1 for the titanium-doped materials. X-ray photoelectron spectroscopy (XPS) shows that there are Ni3+, Ni2+, Co3+, Co2+ and Ti4+ five transition metal ions in titanium-doped materials. Rietveld refinement of X-ray diffraction (XRD) patterns indicates that titanium substitution changes the materials' structure with different cationic distribution. An increase of the Ni/Co amount in the 3a Li site is found with the addition of titanium amount. An improved cycling performance is observed for titanium-doped cathode materials, which is interpreted to a significant suppression of phase transitions and lattice changes during cycling. The thermal stability of titanium-doped materials is also improved, which can be attributed to its lower oxidation ability and enhanced structural stability at delithiated state.