Controlled Nanoparticle Metal Phosphates (Metal = Al , Fe, Ce, and Sr) Coatings on LiCoO2 Cathode Materials

Despite the fact that the same coating concentration and annealing temperature are used for MPO 4 nanoparticle coatings (M = Al, Fe, Ce, and SrH) on a LiCOO 2 cathode, the extent of the coating coverage is influenced by the nanoparticle size or morphology. Nanoparticles (AlPO 4 or FePO 4 ) with a size smaller than 20 nm led to the complete encapsulation of LiCoO 2 , but those with sizes greater than 150 nm (CePO 4 ) or with whisker shapes (SrHPO 4 ) led to partial encapsulation. This difference affected the discharge capacity. The LiCoO 2 completely encapsulated with AlPO 4 or FePO 4 showed the highest discharge capacity of 230 mAh/g at 4.8 and 3 V at a rate of 0.1 C (=18 mA/g), which diminished with decreasing coating coverage in the order of Al ∼ Fe Ce > SrH > Fe > bare cathode. This is consistent with the capacity retention result obtained at 90°C storage for 4 h.

[1]  S Natarajan,et al.  Aufbau principle of complex open-framework structures of metal phosphates with different dimensionalities. , 2001, Accounts of chemical research.

[2]  Doron Aurbach,et al.  On the capacity fading of LiCoO2 intercalation electrodes:: the effect of cycling, storage, temperature, and surface film forming additives , 2002 .

[3]  Zhongru Zhang,et al.  Comparison of Electrochemical and Surface Properties of Bare and TiO2-Coated LiNi0.8Co0.2 O 2 Electrodes , 2004 .

[4]  Jaephil Cho,et al.  Effect of P2O5 and AlPO4 Coating on LiCoO2 Cathode Material , 2003 .

[5]  Lisa C. Klein,et al.  Cobalt dissolution in LiCoO2-based non-aqueous rechargeable batteries , 1996 .

[6]  Jaephil Cho,et al.  Electrochemical Stability of Thin-Film LiCoO2 Cathodes by Aluminum-Oxide Coating , 2003 .

[7]  J. Dahn,et al.  Methods to obtain excellent capacity retention in LiCoO2 cycled to 4.5 V , 2004 .

[8]  A. Dong,et al.  General synthesis of mesoporous spheres of metal oxides and phosphates. , 2003, Journal of the American Chemical Society.

[9]  Ho-jin Kweon,et al.  Surface Modification of LiSr0.002Ni0.9Co0.1 O 2 by Overcoating with a Magnesium Oxide , 1999 .

[10]  Jaephil Cho,et al.  Enhancement of Thermal Stability of LiCoO2 by LiMn2 O 4 Coating , 1999 .

[11]  Jaephil Cho,et al.  Zero-Strain Intercalation Cathode for Rechargeable Li-Ion Cell , 2001 .

[12]  P. Birke,et al.  Materials for lithium thin-film batteries for application in silicon technology , 1996 .

[13]  Jaephil Cho,et al.  Improvement of Structural Stability of LiCoO2 Cathode during Electrochemical Cycling by Sol‐Gel Coating of SnO2 , 1999 .

[14]  J. Dahn,et al.  Effect of a ZrO2 Coating on the Structure and Electrochemistry of Li x CoO2 When Cycled to 4.5 V , 2002 .

[15]  T. Brousse,et al.  Improvement of the Thermal Stability of LiNi0.8Co0.2 O 2 Cathode by a SiO x Protective Coating , 2004 .

[16]  L. Mercier,et al.  Mercury(II) Ion Adsorption Behavior in Thiol-Functionalized Mesoporous Silica Microspheres , 2002 .

[17]  Jaephil Cho,et al.  Complete blocking of Mn3+ ion dissolution from a LiMn2O4 spinel intercalation compound by Co3O4 coating , 2001 .

[18]  M. Haase,et al.  Wet-Chemical Synthesis of Doped Nanoparticles: Optical Properties of Oxygen-Deficient and Antimony-Doped Colloidal SnO2 , 2000 .

[19]  Jaephil Cho,et al.  Improvement of Structural Stability of LiMn2 O 4 Cathode Material on 55 ° C Cycling by Sol‐Gel Coating of LiCoO2 , 1999 .

[20]  Jaephil Cho,et al.  Improved thermal stability of LiCoO2 by nanoparticle AlPO4 coating with respect to spinel Li1.05Mn1.95O4 , 2003 .

[21]  Byungwoo Park,et al.  Novel LiCoO2 Cathode Material with Al2O3 Coating for a Li Ion Cell , 2000 .

[22]  Byungwoo Park,et al.  Effect of microstructures on the microwave dielectric properties of ZrTiO4 thin films , 2001 .

[23]  Jaephil Cho,et al.  A breakthrough in the safety of lithium secondary batteries by coating the cathode material with AlPO4 nanoparticles. , 2003, Angewandte Chemie.

[24]  S. Sze,et al.  Quasi-Superlattice Storage A Concept of Multilevel Charge Storage , 2004 .

[25]  Jaephil Cho.  Stabilization of Spinel-like Phase Transformation of o-LiMnO2 during 55 °C Cycling by Sol−Gel Coating of CoO , 2001 .

[26]  B. Chowdari,et al.  Cathodic performance of anatase (TiO2)-coated Li(Ni0.8Co0.2)O2 , 2002 .

[27]  G. Stucky,et al.  Formation of a Porous Zirconium Oxo Phosphate with a High Surface Area by a Surfactant‐Assisted Synthesis , 1996 .

[28]  M. Haase,et al.  Blue, green, and red upconversion emission from lanthanide-doped LuPO4 and YbPO4 nanocrystals in a transparent colloidal solution. , 2003, Angewandte Chemie.

[29]  Young-Min Choi,et al.  Effects of lithium content on the electrochemical lithium intercalation reaction into LiNiO2 and LiCoO2 electrodes , 1995 .

[30]  Deborah J. Jones,et al.  Surfactant-Assisted Synthesis of a Mesoporous Form of Zirconium Phosphate with Acidic Properties , 1998 .

[31]  J. Dahn,et al.  Improving the Capacity Retention of LiCoO2 Cycled to 4.5 V by Heat-Treatment , 2004 .

[32]  C. Serre,et al.  Hexagonal and Cubic Thermally Stable Mesoporous Tin(IV) Phosphates with Acidic and Catalytic Properties , 2002 .

[33]  M. Haase,et al.  Liquid-Phase Synthesis of Doped Nanoparticles: Colloids of Luminescing LaPO4:Eu and CePO4:Tb Particles with a Narrow Particle Size Distribution , 2000 .