| 초록 |
The cathode material is of particular importance among the components of an LIB, as it contributes significantly to the cost and performance of the battery. Ni-rich layered oxide cathodes provide high capacity that proportionally increases with Ni content; however, they suffer from poor cyclability and thermal instability. These reliability problems associated with Ni-rich cathodes originate from the microcracking of cathode particles, which significantly increases the internal surface exposed to electrolyte attack. One such successful approach to improve the reliability of Ni-rich cathode materials is the introduction of a concentration gradient (CG) in the cathode particle; in fact, CG cathode materials feature in LIBs used in current commercial EVs. In this study, we revisit the full-CG (FCG) cathode material which has demonstrated superior electrochemical performance compared to the conventional, constant concentration cathode materials of similar caliber. By comparing FCG Li[Ni0.78Co0.10Mn0.12]O2 cathodes with differing physical properties, we identify the factors that contribute more or less to the excellent electrochemical performance of the concentration gradient cathodes. |
