Surface structure decoration of high capacity Li1.2Mn0.54Ni0.13Co0.13O2 cathode by mixed conductive coating of Li1.4Al0.4Ti1.6(PO4)3 and polyaniline for lithium-ion batteries

Abstract

The lithium-rich manganese cathode material Li2MnO3·LiMO2 (M = Mn, Co, Ni, Fe, etc.) has been received extensive attention for Li-ion batteries owing to its ultra-high specific capacity (>250 mAh g−1) and lower cost. Nevertheless, it is still strictly challengeable to achieve encouraging Li-storage behaviors due to its poor cyclability, rate performance, and voltage decay. Li-rich manganese cathode material Li1.2Mn0.54Ni0.13Co0.13O2 (LRNCM) modified by a novel hybrid conductive layer constructed with Li1.4Al0.4Ti1.6(PO4)3 (LATP) and polyaniline (PANI) is prepared. The hybrid modification layer (LATP&PANI) not only serves as a physical barrier to protect the active material from the electrolyte, but also combines the high ionic conductivity of Li1.4Al0.4Ti1.6(PO4)3 with the excellent electronic conductivity of polyaniline, helping for facilitating the transfer of electrons and lithium ions. The hybrid modification cathode material (LRNCM@3 wt%LATP@1 wt%PANI) displays favorable rate capability and cycle performance, whose capacity retention (2.0–4.8 V at 0.2 C, 25 °C) deliveries 79% after 200 cycles. The hybrid modification is a promising route for remarkable enhancement in performance of the lithium-rich manganese-based cathode materials.