New insights into aging in LiNiO 2 cathodes from high resolution paramagnetic NMR spectroscopy.

Bulk degradation processes are examined in the LiNiO 2 cathode using high resolution solid-state NMR, combined with magnetometry and X-ray diffraction. Capacity decay is correlated with bulk heterogeneity, whereby multiple structural domains coexist in the charged state, and the Li content and electrochemical activity of these domains is unraveled for the first time.