High capacity Li[Li0.2Mn0.54Ni0.13Co0.13]O2–V2O5 composite cathodes with low irreversible capacity loss for lithium ion batteries

With an aim to suppress the huge irreversible capacity loss encountered in high capacity layered oxide solid solutions between Li2MnO3 and LiMO2 (M = Mn, Ni, and Co), layered Li[Li0.2Mn0.54Ni0.13Co0.13]O2–V2O5 composite cathodes with various V2O5 contents have been investigated. The irreversible capacity loss decreases from 68 mAh/g at 100% Li[Li0.2Mn0.54Ni0.13Co0.13]O2 to 0 mAh/g around 89 wt.% Li[Li0.2Mn0.54Ni0.13Co0.13]O2–11 wt.% V2O5 as the lithium-free V2O5 serves as an insertion host to accommodate the lithium ions that could not be inserted back into the layered lattice after the first charge. The Li[Li0.2Mn0.54Ni0.13Co0.13]O2–V2O5 composite cathodes with about 10–12 wt.% V2O5 exhibit an attractive discharge capacity of close to 300 mAh/g with little irreversible capacity loss and good cyclability.