Improved Performance of Li-Added Mo-Nb Oxide as the Anode for Li-Ion Batteries with N-Carbon Coating

High capacity, fast charging/discharging, safe operation, and long cycle-time are the essential properties of lithium-ion batteries (LiBs) for electric vehicles and large-scale energy storage applications. To meet those properties, an alternative anode has to be developed to replace the traditional graphite electrode. This study aims to demonstrate the effectiveness of Mo-Nb oxide (MNO)-based anode material for fast charging LiB. LiOH is primarily used not only as a source of Li dopant but also as a sintering agent during the solid-state reaction to lower the calcination temperature. After lithium doping, the electrochemical test shows that the C-rate coefficients and capacity retention increase from 12 to 20 C and from 23 to 70.3%, respectively. To further improve the electronic conductivity, Li-added MNO (Li-MNO) is coated with a conductive nitrogen-doped carbon (NC) layer by the pyrolysis method under an argon atmosphere. With more excellent electronic conductivity, the Li-MNO/NC delivers higher specific capacities of 112, 76, and 42 mAhg(-1) at high C-rates of 5, 10, and 20 C, respectively, as compared to the Li-MNO with capacities of 75, 50, and 22.8 mAhg(-1) at the same C-rates. It retains 70% of its capacity after 100 cycles.

Automated summary

This study aims to explore a fast charging lithium-ion battery material as an alternative to the traditional graphite electrode. By using molybdenum-niobium oxide (MNO) as the anode material and lithium doping, along with the coating of a conductive nitrogen-doped carbon layer, the charging speed and capacity retention of the battery were significantly improved.