TY - JOUR
T1 - Reversible Li-intercalation through oxygen reactivity in Li-rich Li-Fe-Te oxide materials
AU - McCalla, Eric
AU - Prakash, Annigere S.
AU - Berg, Erik
AU - Saubanère, Matthieu
AU - Abakumov, Artem M.
AU - Foix, Dominique
AU - Klobes, Benedikt
AU - Sougrati, Moulay Tahar
AU - Rousse, Gwenaelle
AU - Lepoivre, Florent
AU - Mariyappan, Sathiya
AU - Doublet, Marie Liesse
AU - Gonbeau, Danielle
AU - Novak, Petr
AU - Van Tendeloo, Gustaaf
AU - Hermann, Raphäel P.
AU - Tarascon, Jean Marie
N1 - Publisher Copyright:
© 2015 The Electrochemical Society.
PY - 2015
Y1 - 2015
N2 - Lithium-rich oxides are a promising class of positive electrode materials for next generation lithium-ion batteries, and oxygen plays a prominent role during electrochemical cycling either by forming peroxo-like species and/or by irreversibly forming oxygen gas during first charge. Here, we present Li-Fe-Te-O materials which show a tremendous amount of oxygen gas release. This oxygen release accounts for nearly all the capacity during the first charge and results in vacancies as seen by transmission electron microscopy. There is no oxidation of either metal during charge but significant changes in their environments. These changes are particularly extreme for tellurium. XRD and neutron powder diffraction both show limited changes during cycling and no appreciable change in lattice parameters. A density functional theory study of this material is performed and demonstrates that the holes created on some of the oxygen atoms upon oxidation are partially stabilized through the formation of shorter O-O bonds.i.e. (O2)n- species which on further delithiation show a spontaneous O2 de-coordination from the cationic network and migration to the now empty lithium layer. The rate limiting step during charge is undoubtedly the diffusion of oxygen either out along the lithium layer or via columns of oxygen atoms.
AB - Lithium-rich oxides are a promising class of positive electrode materials for next generation lithium-ion batteries, and oxygen plays a prominent role during electrochemical cycling either by forming peroxo-like species and/or by irreversibly forming oxygen gas during first charge. Here, we present Li-Fe-Te-O materials which show a tremendous amount of oxygen gas release. This oxygen release accounts for nearly all the capacity during the first charge and results in vacancies as seen by transmission electron microscopy. There is no oxidation of either metal during charge but significant changes in their environments. These changes are particularly extreme for tellurium. XRD and neutron powder diffraction both show limited changes during cycling and no appreciable change in lattice parameters. A density functional theory study of this material is performed and demonstrates that the holes created on some of the oxygen atoms upon oxidation are partially stabilized through the formation of shorter O-O bonds.i.e. (O2)n- species which on further delithiation show a spontaneous O2 de-coordination from the cationic network and migration to the now empty lithium layer. The rate limiting step during charge is undoubtedly the diffusion of oxygen either out along the lithium layer or via columns of oxygen atoms.
UR - http://www.scopus.com/inward/record.url?scp=84929501514&partnerID=8YFLogxK
U2 - 10.1149/2.0991507jes
DO - 10.1149/2.0991507jes
M3 - Article
AN - SCOPUS:84929501514
SN - 0013-4651
VL - 162
SP - A1341-A1351
JO - Journal of the Electrochemical Society
JF - Journal of the Electrochemical Society
IS - 7
ER -