Abstract
LiNi0.5Mn1.5O4-δ cathode materials with two different structures (F d over(3, ̄) m and P4332) were synthesized by ultrasonic spray pyrolysis method. The X-ray diffraction (XRD) data was confirmed that face-centered spinel (F d over(3, ̄) m) transformed into primitive simple cubic (P4332) structure by annealing process at 700 °C. In spite of two electrons operated cut-off voltage range between 2.0 and 5.0 V, LiNi0.5Mn1.5O4 with P4332 structure has better electrochemical behaviors than the cathode with simple cubic F d over(3, ̄) m structure. Ex situ XRD study of the electrode revealed that LiNi0.5Mn1.5O4 (P4332) has reversible crystal transformation between fully lithiated state (2.0 V) and delithiated state (5.0 V) whereas LiNi0.5Mn1.5O4-δ (F d over(3, ̄) m) showed irreversible phase transformed at two voltage region. The LiNi0.5Mn1.5O4-δ (F d over(3, ̄) m) has voltage drop was occurred after 20th cycled compared without any voltage drop of the P4332 structure.
Original language | English |
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Pages (from-to) | 7226-7230 |
Number of pages | 5 |
Journal | Electrochimica Acta |
Volume | 52 |
Issue number | 25 |
DOIs | |
State | Published - Sep 2007 |
Externally published | Yes |
Funding
This work was supported by University IT Research Center Project.
Keywords
- Cathode materials
- Electrochemical properties
- Li-ion battery
- LiNiMnO
- Spinel materials