Ni₃Sn₄ Electrodes for Li-Ion Batteries: Li−Sn Alloying Process and Electrode/Electrolyte Interface Phenomena

Abstract

We have investigated the reaction mechanisms of lithium toward Ni 3 Sn 4 in an electrochemical cell and the electrode/electrolyte interface phenomena in a combined X-ray photoelectron spectroscopy (XPS) and 119 Sn Mo ¨ssbauer spectroscopy approach, which allows a simultaneous analysis of the surface and of the bulk of the active material particles. We show that 4 mol of lithium per mole of Ni 3 Sn 4 are consumed to form the solid electrolyte interface (SEI) at the first stage of discharge. The composition and behavior of this SEI have been compared to those observed with graphite. The Li-Sn alloying process occurs in the second stage of discharge to form Li 7 Sn 2 . This mechanism is reversible and allows restoring the Ni 3 Sn 4 phase at the end of the cycle.

Electrolyte and Solid-Electrolyte Interphase Layer in Lithium-Ion Batteries

“…A significant chemical surface modification can be observed by the changes of the C1s and O1s core level peaks which indicate that the SEI layer formed on the Sn-Co electrode is composed of Li 2 CO 3 , lithium alkyl carbonate ROCO 2 Li and alcoholates (ROLi). These findings are supported also by XPS analysis of other research groups [Ehinon et al 2008;Dedryvere et al 2006;Naille et al 2006;Leroy et al 2007]. As evidenced by the XPS data [Li et al 2010], the quantity of Li 2 CO 3 in the SEI layer increases with increasing the number of cycling.…”

Nb-Doped TiO2 Nanofibers for Lithium Ion Batteries

“…According to the literature it is mainly the oxygen activity and oxygen affinity of the dopant that determines whether or not surface segregation occurs. 52,53 The possibility of inhomogeneous Nb dopant distribution is not considered since the high solubility of Nb in TiO 2 is widely known. 44,54,55 Theoretical and experimental XAS The Ti K-edge X-ray absorption near edge spectroscopy (XANES) spectra (4966 eV ) of non-doped and Nb-doped TiO 2 are shown in Fig.…”

Mössbauer spectroscopy: analysis and predictions for Li-ion batteries

“…In both cases the first electrochemical cycle leads to the formation of a Li 7 Sn 2 /M 0 nanostructured composite. Ageing is then linked to the reversibility of the reaction which initially depends on the nature of M. For Ni 3 Sn 4 we observe a good reversibility because there is no coalescence of Ni 0 particles during cycling [5]. For FeSn 2 as shown by 57 Fe MS we observe an agglomeration of the Fe 0 particles during cycling and the reversibility doesn't exceed 50 cycles [4].…”

“…FeSn 2 (δ = 2.18 mms −1 , = 0.83 mms −1 ) [4] and Ni 3 Sn 4 (δ = 1.95 mms −1 , = 0.63 mms −1 and δ = 1.98 mms −1 , = 1.37 mms −1 ) [5] are located in the same domain as that of the Li-rich phases (Fig. 1a) and present comparable [e av ] (Fig.…”