Structure and electrochemical properties of C-coated Li₂O–V₂O₅–P₂O₅ glass-ceramic as cathode material for lithium-ion batteries

Abstract

A series of glass cathode materials [Formula: see text]Li 2 O–50V 2 O 5 –(50−[Formula: see text])P 2 O 5 ([Formula: see text], 25, 30, 35 and 40) have been synthesized by a simple melting–quenching method. 30Li 2 O–50V 2 O 5 –20P 2 O 5 glass (LVP30) shows the best cycling performance with a preferable capacity retention after 50 cycles. Then, we prepared a series of carbon-coated LVP30 glass-ceramic cathode materials by carbon coating and heat treatment. The carbon-coated LVP30 samples consist of the crystalline phase V 2 O 3 , VO 2 and Li 2 O–V 2 O 5 –P 2 O 5 glass. Among the carbon-coated LVP30 samples, LVP30-15C sample exhibits the best cycling and rate performance. It can retain a discharge capacity of 140[Formula: see text]mAh[Formula: see text]g[Formula: see text] after 100 cycles. This unique glass-ceramic structure can result in good conductivity and structural ductility.