Improved electrochemical performance of LiCoPO4 nanoparticles for lithium ion batteries.
Single phase LiCoPO4 nanoparticles were synthesized by solid-state reaction. LiCoPO4/Li batteries were fabricated in an argon-filled glove box, and their electrochemical properties were analyzed by cyclic voltammetry (CV) and charge-discharge tests. The structural performance of LiCoPO4 nanoparticles was investigated by X-ray diffraction (XRD) and scanning electron microscope (SEM). The XRD result demonstrated that LiCoPO4 nanoparticles had an orthorhombic olivine-type structure with a space group of Pmnb. The charge-discharge tests indicated that the initial discharge capacity and coulombic efficiency of LiCoPO4/Li batteries were 110 mA h/g and 48% in cut-off voltage range of 3.0-5.3 V, 90 mA h/g and 54% in cut-off voltage range of 3.0-5.1 V, 70 mA h/g and 60% in cut-off voltage range of 3.0-5.0 V, respectively. After 30 cycles, the coulombic efficiency was 78% for 3.0-5.3 V, 88% for 3.0-5.1 V, 91% for 3.0-5.0 V, respectively. These results indicated that the coulombic efficiency of LiCoPO4/Li battery increased upon cycling and upon decreasing in charge upper limit voltage, respectively.
Department of Electrical Engineering, Chonnam National University, Gwangju 500-757, Korea.
Hal-Bon
HB
Gu
Bo
B
Jin
Dae-Kyoo
DK
Jun
Zhenji
Z
Han
D003035:Cobalt / Q000737:chemistry*; D011211:Electric Power Supplies; D004563:Electrochemistry / Q000295:instrumentation* / Q000379:methods; D004735:Energy Transfer; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008094:Lithium / Q000737:chemistry*; D008422:Materials Testing; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D036103:Nanotechnology / Q000295:instrumentation* / Q000379:methods; D010087:Oxides / Q000737:chemistry*; D010316:Particle Size; D010710:Phosphates / Q000737:chemistry*
D010087:Oxides; D010710:Phosphates; C491691:lithium cobalt oxide; D003035:Cobalt; D008094:Lithium