Enhanced Electrochemical Properties of Li2NiTiO4 Cathode by Mo-Doping

Abstract:

Li₂NiTiO₄ with rock-salt structure is a kind of layered cathode materials for lithium ion battery which can extract 2 lithium ions per formula. This material has larger charged capacity, however the reversible discharge capacity is limited. In this Study, molybdenum was doped into Li₂NiTiO₄cell by citric acid sol-gel method using LiNO₃, Ni(NO₃)₂?6H₂O, and Tetrabutyl titanate as starting materials, Mo₇O₂₄ (NH₄)₆?4H₂O as molybdenum source. The structure, micro morphology and elements’ valences were characterized by XRD, SEM and XPS. The electrochemical properties was tested with charge-discharge cycle, CV and EIS. Through Mo-doping, the electrochemical properties was enhanced: the reversible specific capacity was increased from 85mAh/g to162mAh/g. What’s more, when the Mo doped Li₂NiTiO₄ was composited with carbon, the conductivities was improved and the reversible specific capacity further increased to 210mAh/g.

Key words:Li₂NiTiO₄;Lithium ion battery;Citric acid sol-gel method;Cathode material