A 3.90V iron-based fluorosulphate material for lithium-ion batteries crystallizing in the triplite structure

Prabeer Barpanda (1) , Mohammed Ati (1) , Brent C. Melot (1) , G. Rousse (2) , Jean-Noël Chotard (1, 3) , Marie-Liesse Doublet (3, 4) , Moulay Tahar Sougrati (3, 4) , S. A. Corr (5) , Jean-Claude Jumas (3, 4) , Jean‐marie Tarascon (1, 3)

1 LRCS - Laboratoire réactivité et chimie des solides - UMR CNRS 7314
2 IMPMC - Institut de minéralogie et de physique des milieux condensés
3 RS2E - Réseau sur le stockage électrochimique de l'énergie
4 ICGM ICMMM - Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier
5 School of Physical Sciences [Canterbury]

Li-ion batteries have empowered consumer electronics and are now seen as the best choice to propel forward the development of eco-friendly (hybrid) electric vehicles. To enhance the energy density, an intensive search has been made for newpolyanionic compounds that have a higher potential for the Fe2C=Fe3C redox couple. Herein we push this potential to 3.90V in a new polyanionic material that crystallizes in the triplite structure by substituting as little as 5 atomic per cent of Mn for Fe in Li(Fe1 Mn )SO4F. Not only is this the highest voltage reported so far for the Fe2C=Fe3C redox couple, exceeding that of LiFePO4 by 450mV, but this new triplite phase is capable of reversibly releasing and reinserting 0.7-0.8 Li ions with a volume change of 0.6% (compared with 7 and 10% for LiFePO4 and LiFeSO4F respectively), to give a capacity of 125mAh g1.

Domaines: Science des matériaux [cond-mat.mtrl-sci]

Prabeer Barpanda, Mohammed Ati, Brent C. Melot, G. Rousse, Jean-Noël Chotard, et al.. A 3.90V iron-based fluorosulphate material for lithium-ion batteries crystallizing in the triplite structure. Nature Materials, 2011, pp.ASAP. ⟨10.1038/nmat3093⟩. ⟨hal-00616298⟩