Lithium transport investigation in LixFeSiO4: A promising cathode material
2013 (English)In: Solid State Communications, ISSN 0038-1098, E-ISSN 1879-2766, Vol. 173, 9-13 p.Article in journal (Refereed) Published
In this paper we investigate lithium mobility in both Li 2FeSiO4 and its half-lithiated state LiFeSiO4 considering an orthorhombic crystal structure. We find that the calculated activation energy of Li+ ions hopping between adjacent equilibrium sites predicts two least hindered diffusion pathways in both materials. One of them is along the  direction characterizing an ionic diffusion in a straight line and the other follows a zig-zag way between the Fe-Si-O layers. We also show that diffusion of Li+ ions in the half-lithiated structure follows the same behavior as in the lithiated structure. As a whole, the activation energies for the investigated compounds present a greater value compared with the activation energies in currently used materials such as LiFePO4. The results were calculated in the framework of density functional theory in conjunction with the climbing image nudged elastic band method. The Hubbard term was added to the Kohn-Sham Hamiltonian to overcome the delocalization problem of d electrons. Furthermore, the diffusion coefficients were calculated for both structures considering temperatures ranging from 300 to 700 K.
Place, publisher, year, edition, pages
2013. Vol. 173, 9-13 p.
A. Lithium-ion battery material, D. Electronic properties, D. Ionic diffusion properties
Engineering and Technology
IdentifiersURN: urn:nbn:se:kth:diva-133163DOI: 10.1016/j.ssc.2013.08.025ISI: 000330919200003ScopusID: 2-s2.0-84884751276OAI: oai:DiVA.org:kth-133163DiVA: diva2:660208
FunderSwedish Research CouncilSwedish Energy AgencyStandUp
QC 201310292013-10-292013-10-282014-03-06Bibliographically approved