Li-ion batteries, as a type of clean energy storage device and with the highest energy density in secondary batteries, are much superior to conventional chemical power sources and have attracted much attention.

Yong-Sheng Hu and colleagues, Chinese Academy of Sciences, Beijing, China, demonstrate a new approach to modify the Li₄Ti₅O₁₂ electrode material by using urea as a precursor. This is achieved by simply mixing Li₄Ti₅O₁₂ and urea uniformly and then pyrolyzing the mixture at a rather low temperature of 400 °C. The coated sample with a very thin and uniform C–N compound layer exhibits improved rate capability and excellent cycling performance.

This surface modification is relatively simple and inexpensive and might be a helpful approach to solve the problem of gas release in Li₄Ti₅O₁₂-based batteries. Further work is required to determine the composition and to elucidate the functions of the C–N compound.

• Improved Li-Storage Performance of Li₄Ti₅O₁₂ Coated with C–N Compounds Derived from Pyrolysis of Urea through a Low-Temperature Approach,
  Huilin Pan, Liang Zhao, Yong-Sheng Hu, Hong Li, Liquan Chen,
  ChemSusChem 2011.
  DOI: 10.1002/cssc.201100629