Li4Ti5O12 heattreated under nitrogen ambient with outstanding rate capabilities

Abstract

The powders of spinel Li4Ti5O12 were prepared by heat treating the mixture of rutile Ti O 2 and Li acetate at 800°C for 3h under a nitrogen atmosphere and, for comparison, under air as well. The powders heated under N 2 show a remarkably higher-rate capability and better cycle stability. The discharge capacity of Li4Ti 5O12 heated under N2 at 19°C (corresponding to a 3.2-minute total discharge) reached 107mA hg-1, 22mA hg -1 higher than that of Li4Ti5O12 heated under air, which was 85mA h g-1. The former material also shows a much better cycle stability, with no discharge capacity loss after 300 cycles at 6°C or 16.3°C. The results indicate that heat treatment under low-oxygen partial pressure atmosphere such as N2 could significantly improve the high-rate performance of spinel Li4Ti5O 12. Copyright © 2011 Rui Xu et al.