A lithium-ion battery including a negative electrode (anode) containing lithium titanate oxide (Li 4 Ti 5 O 12 ) (LTO) as an active material and a stable interface layer disposed on a surface of the electrode; a positive electrode (cathode); an electrolyte containing a solvent and an impedance growth reducing additive; and a separator disposed between the electrodes. The LTO-based cell with the stable interface layer on the negative electrode is formed by holding the potential of the negative electrode below the reduction potential of the impedance growth reducing additive for a sufficient length of time during a first formation cycle. The stable interface layer on the negative electrode mitigates impedance growth on the positive electrode over cycle life. When the impedance growth reducing additive is fluoroethylene carbonate (C 3 H 3 FO 3 ), the stable interface layer includes a LiF deposit.