Tuesday, 21 June 2016
Riverside Center (Hyatt Regency)
Y. Shin, O. Kahvecioglu Feridun, and G. Krumdick (Argonne National Laboratory)
Nickel-rich cathode material, LiNi
0.8Co
0.1Mn
0.1O
2, exhibits high specific capacity of approximately 200 mAh/g-oxide and potential for use in plug-in hybrid electric vehicles. However, significant challenges remain to improve the cycle life and thermal-abuse tolerance of this material. To improve the stability of this material, several researchers have investigated a core-shell approach resulted in a nickel-rich LiNi
0.8Co
0.1Mn
0.1O
2 core and a manganese-rich LiNi
0.5Mn
0.5O
2shell for surface stabilization [1]. However, the structural mismatch between the core and shell compositions leads to large void formation at the core-shell interface which triggers a sudden drop in capacity after long-term cycling. To overcome the volume change between the core and shell compositions, concentration gradient shell was investigated [2] and full concentration gradient material was suggested which shows the gradual decrease of nickel concentration and increase of manganese concentration from the centre towards the outer layer of the particle [3].
Even though many researchers showed the promising high energy, long calendar life and excellent abuse tolerance of core-shell, core-concentration gradient shell and full concentration gradient materials by their synthesis optimization, the compared nominal composition of LiNi0.8Co0.1Mn0.1O2 was not well-optimized. Here, we report the optimized synthesis condition of a nominal composition of LiNi0.8Co0.1Mn0.1O2, core-shell and core-concentration gradient shell materials with LiNi0.4Co0.2Mn0.4O2 surface composition. The detailed comparison of the physical and electrochemical properties of the prepared materials will be discussed.
References
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