An effective way of co-precipitating Ni2+, Mn2+ and Co2+ by using ammonium oxalate as precipitant for Ni-rich Li-ion batteries cathode

An oxalate-based hydrothermal approach has been applied to synthesize Ni 0.8 Mn 0.1 Co 0.1 ·C 2 O 4 ·2H 2 O “mixed oxalate,” and “mixed oxalate” has been lithiated to LiNi 0.8 Mn 0.1 Co 0.1 O 2 for Li-ion batteries cathode. Ni 2+ , Mn 2+ and Co 2+ can be precipitated quickly and effectively at 100 °C within 20 min without inert gas protection, and it was not needed to control the pH of the solution deliberately. After the “mixed oxalate” was lithiated to LiNi 0.8 Mn 0.1 Co 0.1 O 2 , as-synthesized LiNi 0.8 Mn 0.1 Co 0.1 O 2 can deliver 160–180 mAh g −1 at 1C during long-term cycling and showed one of the best electrochemical performances compared to some Ni-rich or Ni/Mn/Co-contained cathodes synthesized by similar procedures, i.e., higher reversible capacity in rate charge/discharge cycles. Considering the facile synthesis of “mixed oxalate,” this work may give rise to an inspiration for LiNi x Mn y Co 1− x − y O 2 cathodes research.