Correlation between irreversible capacity and electrolyte solvents degradation probed by NMR in Si-based negative electrode of Li-ion cell
Résumé
Few studies relate that the failure mechanism of silicon-based electrodes is the SEI formation. In this work, we used quantitative solid-state high-resolution nuclear magnetic resonance to show that main cause of irreversible capacity is not the decomposition of lithium salt but the degradation of electrolyte solvent with the formation of non lithiated carbon species as polymer or oligomers.
Mots clés
Lithium ion batteries
Electrical characteristic
NMR spectrometry
Cross polarization
Solid state
Secondary cell
Electrode material
Capacitance
Irreversible process
Solvent effect
Cycling
Electrolyte solution
Organic carbonate
Silicon
Anode
Lithium Hexafluophosphates
Degradation
Organic solvent
Carbon 13
Lithium 7
Fluorine 19
Magic angle