||The characterization and electrochemical performance of Li[Li0.2Ni0.4Mn0.4]O2, material prepared by a combustion method
||Yan, W.; Wen, H.; Chen, Y. Z*; Wang, Y.; Liu, Y.
||Journal of Power Sources
||A Li[Li0.2Ni0.4Mn0.4]O2 cathode material for lithium battery was synthesized in de-ionized water, ethanol
and ethanol with PEG by a combustion method. XPS analysis shows that Ni and Mn are in 3þ and 4þ
oxidation states, respectively. Three materials exhibit a layered hexagonal a-NaFeO2 structure, and that
prepared in ethanol with PEG displays the best homogeneous morphology in a size distribution of 200
e400 nm. The electrochemical tests show that the material prepared in ethanol with PEG displays the
best cyclic performance and rate capability, such as the discharge capacity of 254 mAhg1 in the first
cycle at 0.1C and 234 mAhg1 after 50 cycles. Capacity retention is more than 90% after 50 cycles for the
cell with a charge/discharge pre-cycling treatment (one cycle at 4.5e2.0 V and followed by one cycle at
4.8e2.0 V) compared with that without pre-cycling. EIS measurements demonstrate that pre-cycling
treatment leads to form a better SEI layer and the cell assembled with the material prepared in
ethanol with PEG has the least RSEI and Rct values.