Cycle life improvement of ZrO{sub 2}-coated spherical LiNi{sub 1/3}Co{sub 1/3}Mn{sub 1/3}O{sub 2} cathode material for lithium ion batteries Hu, Shao-Kang; Cheng, Geng-Hao; Cheng, Ming-Yao; Santhanam, Raman [Nanoelectrochemistry Laboratory, Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei 106 (China)]; Hwang, Bing-Joe [Nanoelectrochemistry Laboratory, Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei 106 (China)]; National Synchrotron Radiation Research Center, Hsinchu 300 (China)] 25 ENERGY STORAGE; CATHODES; LITHIUM; SYNTHESIS; PRECIPITATION; SPRAY DRYING; PRECURSOR; HEAT TREATMENTS; HEATING; STABILITY; SPINELS; POWDERS; SURFACES; LAYERS; CUTTING; ELECTRIC POTENTIAL; X-RAY DIFFRACTION; IMPEDANCE; SPECTROSCOPY; POLARIZATION; PERFORMANCE; ELECTROLYTES; DECOMPOSITION; SURFACE COATING; ZIRCONIUM OXIDES; LITHIUM OXIDES; NICKEL OXIDES; COBALT OXIDES; MANGANESE OXIDES; ELECTRIC BATTERIES; MANGANESE; Spherical LiNi{sub 1/3}Co{sub 1/3}Mn{sub 1/3}O{sub 2}; ZrO{sub 2} coating; Cycling performance; Lithium battery Spherical LiNi{sub 1/3}Co{sub 1/3}Mn{sub 1/3}O{sub 2}; ZrO{sub 2} coating; Cycling performance; Lithium battery A modified synthesis process was developed based on co-precipitation method followed by spray drying process. In this process, a spherical shaped (Co{sub 1/3}Ni{sub 1/3}Mn{sub 1/3})(OH){sub 2} precursor was synthesized by co-precipitation and pre-heated at 500 C to form a high structural stability spinel (CoNiMn)O{sub 4} to maintain its shape for further processing. The spherical LiNi{sub 1/3}Co{sub 1/3}Mn{sub 1/3}O{sub 2} was then prepared by spray drying process using spherical spinel (CoNiMn)O{sub 4}. LiNi{sub 1/3}Co{sub 1/3}Mn{sub 1/3}O{sub 2} powders were then modified by coating their surface with a uniform and nano-sized layer of ZrO{sub 2}. The ZrO{sub 2}-coated LiNi{sub 1/3}Co{sub 1/3}Mn{sub 1/3}O{sub 2} material exhibited an improved rate capability and cycling stability under a high cut-off voltage of 4.5 V. X-ray diffraction (XRD) measurements revealed that the material had a well-ordered layered structure and Zr was not doped into the LiNi{sub 1/3}Co{sub 1/3}Mn{sub 1/3}O{sub 2}. Electrochemical impedance spectroscopy measurements showed that the coated material has stable cell resistance regardless of cycle number. The interrupt charging/discharging test indicated that the ZrO{sub 2} coating can suppress the polarization effects during the charging and discharging process. From these results, it is believed that the improved cycling performance of ZrO{sub 2}-coated LiNi{sub 1/3}Co{sub 1/3}Mn{sub 1/3}O{sub 2} is attributed to the ability of ZrO{sub 2} layer in preventing direct contact of the active material with the electrolyte resulting in a decrease of electrolyte decomposition reactions. (author) Available from: http://dx.doi.org/10.1016/j.jpowsour.2008.11.113 Netherlands 2009-03-15 English Journal Article Journal Name: Journal of Power Sources; Journal Volume: 188; Journal Issue: 2; Other Information: Elsevier Ltd. All rights reserved Medium: X; Size: page(s) 564-569 https://doi.org/10.1016/J.JPOWSOUR.2008.11.113 [] 2 188 Journal ID: ISSN 0378-7753; JPSODZ; TRN: NL09V3539 ECN 2010-01-01 21168693