Microstructural and electrochemical properties of Ti-doped Al2O3 coated LiCoO2 films

Abstract

We studied the microstructural and electrochemical properties of Ti-doped Al2O3 (Ti-Al2O3) coated LiCoO2 thin films depending on the Ti composition. The 1.27 at.% Ti-Al2O3 coated films had an amorphous structure with better conductivity than that of pure Al2O3 films. The Ti-Al2O3 coating layer effectively suppressed the dissolution of Co and the formation of lower Li conductivity SEI films at the interface between the LiCoO2 film and electrolyte. The Ti-Al2O3 coating improved the cycling performance and capacity retention at high voltage (4.5 V) of the LiCoO2 films. The Ti-Al2O3 coated LiCoO2 films showed better electrochemical properties than did the pure Al2O3 coated LiCoO2 films. These results were closely related to the enhanced Li-conductivity and interfacial quality of the Ti-Al2O3 film.

Vapor-assisted synthesis of Al2O3-coated LiCoO2 for high-voltage lithium ion batteries

“…On the one hand, there is doping with metal elements, for instance, Al [6], Mg [7][8][9], Cu [10], Zr [9], Ti [11], and La [12]. On the other hand, there is coating with oxides, such as MgO [3], CeO 2 [13], Fe 2 O 3 [14], ZrO 2 [15][16][17][18][19], TiO 2 [20,21], ZnO [22], and Al 2 O 3 [4,[23][24][25]. The coating layer can greatly improve the capacity retention during cycling by reducing changes in the lattice parameters and decreasing cobalt dissolution.…”