High rate capability of a BaTiO3-decorated LiCoO2 cathode prepared via metal organic decomposition

Metal organic decomposition (MOD) using octylic acid salts was applied to synthesize a BaTiO3–LiCoO2 (BT–LC) composite powder. The Ba and Ti octylates were utilized as metal precursors, in an attempt to synthesize homogeneous BT nanoparticles on the LC matrix. The BT–LC composite, having a phase-separated composite structure without any impurity phase, was successfully obtained by optimizing the MOD procedure. The composite prepared using octylate precursors exhibited a sharper distribution and better dispersibility of decorated BT particles. Additionally, the average particle size of the decorated BTs using metal octylate was reduced to 23.3 nm, compared to 44.4 nm from conventional processes using Ba acetate as well as Ti alkoxide as precursors. The composite cathode displayed better cell performance than its conventional counterpart; the discharge capacity of the metal octylate-derived specimen was 55.6 mAh/g at a 50C rate, corresponding to 173% of the capacity of the conventional specimen (32.2 mAh/g). The notable improvement in high rate capability obtained in this study, compared with the conventional route, was attributed to the higher density of the triple junction formed by the BT–LC–electrolyte interface.