Electrochemical Characteristics of Anion-Redox Type Cathode Materials with High Specific Capacity

摘要

In recent years, high energy-density lithium-ion batteries have been used for power sources such as hybrid and electric vehicles and for home energy storage systems. However, with increasing performance of equipment, energy storage devices with higher energy density than conventional lithium-ion batteries are required. Co-doped Li_2O (CDL), which utilizes the redox reaction of oxygen for charge compensation, has been investigated as such a material. In this material, Co plays a role in improving the electrochemical activity of oxygen; CDL has a high specific capacity of about 450 mAh g~(-1), but there is a problem of the active material decomposition when overcharged. In this work, Me-Li_2O-MO_X (Me: transition metal, M: Al and Si) was investigated to suppress the degradation reaction of active materials by simultaneously dissolving oxides such as Al_2O_3 without 3d orbitals and transition metal oxides with 3d orbitals in Li_2O.