New concentration-gradient cathode material for Li-ion batteries shows high energy density and long life
Researchers from Korea and the US have developed a new concentration-gradient Li[Ni0.83Co0.07Mn0.10]O2 cathode material that offer high energy capacity and stability. The team of has published earlier on the benefits of the concentration-gradient approach. (Earlier post.) Their latest paper appears in the RSC Journal of Materials Chemistry.
|Discharge capacity and cycles for the core material and the new concentration gradient material. Credit: RSC, Sun et al. Click to enlarge.|
The new material was successfully synthesized via co-precipitation, in which the core Li[Ni0.9Co0.05Mn0.05]O2 was encapsulated completely with a stable concentration-gradient layer having reduced Ni content.
Compared to the core material alone, the new concentration-gradient material had a superior lithium intercalation stability and thermal stability. The high capacity was delivered from the Ni-rich core Li[Ni0.9Co0.05Mn0.05]O2, and the improved thermal stability was achieved by the Ni-depleted concentration-gradient layer with outer surface composition of Li[Ni0.68Co0.12Mn0.20]O2.
The concentration-gradient materials open a new era for the development of advanced Li-ion batteries with high energy density, long cycle life, and improved safety, the team said.
Yang-Kook Sun, Bo-Ram Lee, Hyung-Ju Noh, Huiming Wu, Seung-Taek Myung and Khalil Amine (2011) A novel concentration-gradient Li[Ni0.83Co0.07Mn0.10]O2 cathode material for high-energy lithium-ion batteries. J. Mater. Chem., 2011, Advance Article doi: 10.1039/C0JM04242K