Cationic and Anionic Vacancy-Dependent Memory Effect in TiO2

Abstract

Nickel-cadmium and nickel-metal hydride batteries exhibit voltage deviations due to usage history, and this process is referred to as the memory effect. Recently, it has been revealed that lithium-ion intercalation materials with a flat voltage plateau are also susceptible to a memory effect that complicates their state-of-charge estimation. The memory effect in TiO2 is known to be affected by particle size and Li-ion mobility. Here, we report that the type of vacancies in TiO2 is also critical to dictate the extent of the memory effect in TiO2.