Synthesis of Monoclinic Li[Li 0.2 Mn 0.54 Ni 0.13 Co 0.13 ]O 2 Nanoparticles by a Layered‐Template Route for High‐Performance Li‐Ion Batteries

Nanocrystalline Li[Li 0.2 Mn 0.54 Ni 0.13 Co 0.13 ]O 2 was prepared by a layered‐template method and was tested as a high‐capacity and high‐power cathode for Li‐ion batteries. Structural characterization demonstrates that the Li[Li 0.2 Mn 0.54 Ni 0.13 Co 0.13 ]O 2 nanoparticles have a high crystallinity with a monoclinic ( C /2 m ) structure. This material exhibits an initial discharge capacity of 277.4 mAh g –1 and a high coulombic efficiency of 87.3 %, with a very small capacity fade of 0.046 % per cycle over 100 cycles. Such excellent electrochemical performance is likely to result from its monoclinic structure that enables a stable solid solution structure and reversible structural changes during cycling. Therefore, monoclinic Li[Li 0.2 Mn 0.54 Ni 0.13 Co 0.13 ]O 2 may meet the high‐capacity and high‐rate requirements for an alternative cathode for a new generation of Li‐ion batteries.