Direct electrodeposition of lithium titanate as a lithium-ion battery anode active material in propylene carbonate solution containing titanyl compounds.

Lithium titanium oxide (LTO) type materials for lithium-ion (Li-ion) batteries have become an alternative to the typically used graphitic-based materials as anode materials due to their better safety performance and longer life cycles. In the literature, LTO structures such as LiTiO, LiTiO and LiTiO/LiTiO composites with different Li/Ti ratios have been synthesized by solution and solid phase methods such as sol-gel, spray drying, spray pyrolysis and, ultrasonic spray pyrolysis at elevated temperatures using TiO and LiCO as starting materials, and their electrochemical performances have been tested. This study demonstrated that electrochemical deposition can directly deposit LTO anode electrode materials using TiOSO and TiO(ClO) precursor compounds in Propylene Carbonate (PC) solvent containing LiClO supporting electrolyte at room temperature. TiO(OH) and TiOOH, which are formed by the reactions of the unstable TiO ion formed by electrochemical reduction with TiO in solution and adsorbed on the electrode surface and the OH ion formed by the electroreduction of water, and TiO(OH) and TiOOH precipitated on the electrode surface, interact with the excessive amount of Li ions in solution to form lithium titanate. Since electrochemical reduction occurs between 2.4 V and 1.2 V, lithium can be incorporated during electrodeposition, resulting in the formation of various lithium titanate phases (LiTiO, LiTiO and LiTiO/LiTiO composite). Electrodeposited Lithium Titanate (ED-LTO) obtained in this way has been characterized using cyclic voltammetry, chronopotentiometry, EIS, XRD, XPS, Raman spectroscopy, and FESEM-EDX techniques. A full cell was fabricated using ED-LTO/LiFePO.