Evidence of enhanced ion transport in Li-rich silicate intercalation materials
Abstract
The silicate compounds Li2MSiO4 (where M = Mn, Fe, Co) have received significant attention recently as Li intercalation electrodes. Overwhelmingly they exhibit relatively poor kinetics of ion intercalation. By synthesizing Li-rich solid solutions of the form Li2+2xFe1−xSiO4 (with 0 ≤ x ≤ 0.3), the structural requirements for fast ion transport and hence relatively fast intercalation have been identified. Specifically the presence of additional Li+ in interstitial sites, not normally occupied in the stoichiometric Li2FeSiO4 compound, enhances ion transport by more than two orders of magnitude. The results, obtained by combining electrochemical measurements, with powder X-ray and neutron diffraction and atomistic modeling of the ion dynamics, provide valuable guidance in designing future intercalation electrodes with high Li-ion transport and, hence, fast electrode kinetics.
Citation
Billaud , J , Eames , C , Tapia-Ruiz , N , Roberts , M R , Naylor , A J , Armstrong , A R , Islam , M S & Bruce , P G 2017 , ' Evidence of enhanced ion transport in Li-rich silicate intercalation materials ' , Advanced Energy Materials , vol. 7 , no. 11 , 1601043 . https://doi.org/10.1002/aenm.201601043
Publication
Advanced Energy Materials
Status
Peer reviewed
ISSN
1614-6832Type
Journal article
Description
Financial support from the EPSRC Supergen Energy Storage Consortium (EP/L019469/1) and the Energy Materials Programme Grant (EP/K016288) is gratefully acknowledged.Collections
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