TY - JOUR
T1 - Electrochemical properties of yolk-shell structured layered-layered composite cathode powders prepared by spray pyrolysis
AU - Kim, Jung Hyun
AU - Kang, Yun Chan
AU - Choi, Yun Ju
AU - Kim, Yang Soo
AU - Lee, Jong Heun
N1 - Funding Information:
This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MEST) (No. 2012R1A2A2A02046367).
Publisher Copyright:
© 2014 Elsevier Ltd. All rights reserved.
PY - 2014/10/20
Y1 - 2014/10/20
N2 - Layered-layered yolk-shell powders with composition 0.6Li(Li1/3Mn2/3)O2· 0.4Li(Ni1/3Co1/3Mn1/3)O2are prepared by spray pyrolysis. Metal oxides-carbon composite powders are first formed as an intermediate product near the reactor entrance by drying and decomposition of droplets. Combustion, contraction, and recombustion processes of intermediate product produce yolk-shell-structured powders. The yolk-shell structure of the powders prepared directly by spray pyrolysis is maintained even after post-treatment at 800 °C; this treatment temperature yields the best electrochemical performance. The composition of the powders post-treated at 800 °C is Li1.12Ni0.14Co0.14Mn0.59O2. Mean grain sizes of the yolk-shell 0.6Li(Li1/3Mn2/3)O2·0.4Li(Ni1/3Co1/3Mn1/3)O2powders, post-treated at 700, 750, and 800 °C, measured from high resolution TEM images, are 47, 54, and 79 nm, respectively, and their BET surface areas are 14, 9, and 7 m2g-1. The initial discharge capacities of the powders, post-treated at the above temperatures, are 188, 280, and 239 mA h g-1, respectively, and their initial Coulombic efficiencies are 87, 80, and 78%. Discharge capacities after 50 cycles of the post-treated powders are 81, 194, and 183 mA h g-1, respectively, and the corresponding capacity retentions are 43, 70, and 77%.
AB - Layered-layered yolk-shell powders with composition 0.6Li(Li1/3Mn2/3)O2· 0.4Li(Ni1/3Co1/3Mn1/3)O2are prepared by spray pyrolysis. Metal oxides-carbon composite powders are first formed as an intermediate product near the reactor entrance by drying and decomposition of droplets. Combustion, contraction, and recombustion processes of intermediate product produce yolk-shell-structured powders. The yolk-shell structure of the powders prepared directly by spray pyrolysis is maintained even after post-treatment at 800 °C; this treatment temperature yields the best electrochemical performance. The composition of the powders post-treated at 800 °C is Li1.12Ni0.14Co0.14Mn0.59O2. Mean grain sizes of the yolk-shell 0.6Li(Li1/3Mn2/3)O2·0.4Li(Ni1/3Co1/3Mn1/3)O2powders, post-treated at 700, 750, and 800 °C, measured from high resolution TEM images, are 47, 54, and 79 nm, respectively, and their BET surface areas are 14, 9, and 7 m2g-1. The initial discharge capacities of the powders, post-treated at the above temperatures, are 188, 280, and 239 mA h g-1, respectively, and their initial Coulombic efficiencies are 87, 80, and 78%. Discharge capacities after 50 cycles of the post-treated powders are 81, 194, and 183 mA h g-1, respectively, and the corresponding capacity retentions are 43, 70, and 77%.
KW - Cathode material
KW - Layered material
KW - Lithium ion batteries
KW - Spray pyrolysis
KW - Yolk-shell
UR - http://www.scopus.com/inward/record.url?scp=84907100355&partnerID=8YFLogxK
U2 - 10.1016/j.electacta.2014.08.015
DO - 10.1016/j.electacta.2014.08.015
M3 - Article
AN - SCOPUS:84907100355
SN - 0013-4686
VL - 144
SP - 288
EP - 294
JO - Electrochimica Acta
JF - Electrochimica Acta
ER -
