The Doping of FeNb 11 O 29 as a Way to Improve Its Electrochemical Performances

FeNb 11 O 29 , with the possibility to exchange up to 23 electrons per formula unit and a theoretical capacity value of 400 mAh/g, is nowadays a very promising anode material for Li‐ion batteries. However, the improvement of its electrochemical performances is still an open challenge, and the doping is a well‐recognized method to obtain this goal. In this paper, orthorhombic Fe 0.8 Mn 0.2 Nb 11 O 29 and Fe 0.8 V 0.2 Nb 11 O 29 samples were prepared by solid state synthesis. The redox processes, as determined by cyclic voltammetry, involve only Fe and Nb ions as in the undoped compound. FeNb 11 O 29 is a well‐known mixed oxide with pseudocapacitive behavior, which is increased with the Mn doping. The doped samples show better performances during long term cycling at 2 C, with capacities of 240 and 220 mAh/g and capacity retention of 100.9 and 98.7% for Mn and V doped respectively.