New chemical approach to obtain dense layer phosphate-based ionic conductor coating on negative electrode material surface: Synthesis way, outgassing and improvement of C-rate capability

[Display omitted] •Dense layer coating of based-phosphate ionic conductor obtained by spray-drying.•Influence of dense ionic conductor at the negative surface material on performances.•Impact of dense ionic conductor coating on outgassing phenomena. Li4Ti5O12 (LTO) based batteries have severe gassin...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Veröffentlicht in:Applied surface science 2017-04, Vol.400, p.139-147
Hauptverfasser: Fleutot, Benoit, Davoisne, Carine, Gachot, Grégory, Cavalaglio, Sébastien, Grugeon, Sylvie, Viallet, Virginie
Format: Artikel
Sprache:eng
Schlagworte:
Online-Zugang:Volltext
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
Beschreibung
Zusammenfassung:[Display omitted] •Dense layer coating of based-phosphate ionic conductor obtained by spray-drying.•Influence of dense ionic conductor at the negative surface material on performances.•Impact of dense ionic conductor coating on outgassing phenomena. Li4Ti5O12 (LTO) based batteries have severe gassing behavior during charge/discharge and storage process, due to interfacial reactions between active material and electrolyte solution. In the same time, the electronic and ionic conductivity of pristine LTO is very poor and induces the use of nanoparticles which increase the outgassing phenomena. The coating of LTO particles could be a solution. For this the LTO spinel particles are modified with ionic conductor Li3PO4 coating using a spray-drying method. For the first time a homogeneous thin dense layer phosphate based conductor is obtained without nanoparticles, as a thin film material. It is so possible to study the influence of ionic conductor deposited on the negative electrode material on performances by the controlled layer thickness. This coating was characterized by XRD, SEM, XPS and TEM. The electrochemical performance of Li3PO4 coated Li4Ti5O12 is improved at high C-rate by the surface modification (improvement of 30mAhg−1 at 5 C-rate compared to pristine LTO for 5nm of coating), inducing by a modification of surface energy. An optimum coating thickness was studied. This type of coating allows a significant decrease of outgassing phenomena due the conformal coating and opens the way to a great number of studies and new technologies.
ISSN:0169-4332
1873-5584
DOI:10.1016/j.apsusc.2016.12.178