7Li and 1H MAS NMR observation of interphase layers on lithium nickel oxide based positive electrodes of lithium-ion batteries

Michel Ménétrier (1) , Christophe Vaysse (1) , Laurence Croguennec (1) , Claude Delmas (1) , Christian Jordy (2) , Frans Bonhomme (2) , Philippe Biensan (2)

1 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux
2 SAFT - Société des accumulateurs fixes et de traction

7Li and 1H magic-angle spinning (MAS) NMR spectra were recorded for Li(Ni,Co,Al)O2 samples. The 7Li MAS NMR signal of the layer on the pristine material is close to that of Li2CO3 in close contact with it. Its lineshape, due to dipolar interaction with electron spins of the material, is drastically different from that of pure Li2CO3. Upon hydration, this layer grows, while 1H NMR suggests that some lithium in the material is replaced by protons. Upon electrochemical cycling, the original layer is replaced by a different one, the solid electrolyte interphase, with distinct 7Li and 1H NMR signatures, showing its largely organic nature.

Mots clés: Positive electrode; Lithium ion batteries; Lithium nickel oxide; Interphase layers; Nuclear magnetic resonance

Domaines: Matériaux

Michel Ménétrier, Christophe Vaysse, Laurence Croguennec, Claude Delmas, Christian Jordy, et al.. 7Li and 1H MAS NMR observation of interphase layers on lithium nickel oxide based positive electrodes of lithium-ion batteries. Electrochemical and Solid-State Letters, 2004, 7 (6), pp.A140-A143. ⟨10.1149/1.1697905⟩. ⟨hal-00150116⟩