Improved rate capability of the conducting functionalized FTO-coated Li-[Li0.2Mn0.54Ni0.13Co0.13]O2 cathode material for Li-ion batteries

Abstract

Layered FTO-coated Li[Li_0.2Co_0.13Ni_0.13Mn_0.54]O₂ (FTO-LRMO) nanoparticles were synthesized by a simple polymer-pyrolysis method and then coated with F_0.3–SnO₂ (FTO) to form a conductive protection layer. The FTO-LRMO electrode demonstrates a high initial columbic efficiency of 88%, a large reversible capacity of ∼296 mA h g⁻¹, and an excellent cyclability with 83% capacity retention after 300 cycles. Particularly, this material can deliver a quite high capacity of 164 mA h g⁻¹ at a high rate of 2400 mA g⁻¹, exhibiting excellent rate capability. This superior electrochemical performance results from the conducting functionalized surface modification, which not only offers an effective protection layer to form a stable SEI film and maintain the stability of the interface structure, but also decreases the interface and reaction impedance by the conductive coating. Therefore, the conducting functionalized coating by FTO is a simple, effective and novel way to enhance the electrochemical performance of lithium-rich Mn-based oxide cathodes for practical battery applications.