Charge compensation mechanisms in Li1.16Ni0.15Co0.19Mn0.50O2 positive electrode material for Li-ion batteries analyzed by a combination of hard and soft X-ray absorption near edge structure

► The redox reaction was studied by using hard and soft XANES spectroscopies. ► During the charge at a voltage plateau, some of the Ni and Co ions are reduced. ► We report the partial reduction of Ni and Co is associated with the ion migration. ► Soft XANES is effective to distinguish some of the surface specific reactions.