Understanding the impact of high-voltage cycling on the structural stability of cobalt-free LiNiO2 using operando neutron diffraction

To increase discharge capacity in layered transition metal oxides as cathodes for Li-ion batteries, higher Ni loadings are being utilised. This has recently renewed interest in the species LiNiO2 (LNO) as the end member of this series. The increased capacity overserved for LNO comes with a number of complex, sharp phase changes during cycling, particularly at high voltages, which result in increased capacity but rapid capacity fading. This is accompanied by a dynamic interplay between the different atom pairs in the structure which cause a wide range of effects in the structure. We propose to study these phenomena by using operando neutron diffraction during high-voltage charge/discharge to collect, and subsequently analyse, both the Bragg and Total Scattering data. This study will aid efforts to mitigate the capacity fade and improve the performance of LNO.