Lithium Diffusion & Magnetism in Battery Cathode Material LixNi1/3Co1/3Mn1/3O2

TL;DR

This study investigates the magnetic and lithium ion diffusion properties of LixNi1/3Co1/3Mn1/3O2, revealing a 2D spin-glass state at low temperatures and thermally activated lithium diffusion with an energy barrier of 100 meV.

Contribution

It provides new insights into the magnetic state and lithium diffusion mechanisms in this cathode material using muon spin rotation/relaxation techniques.

Findings

Samples enter a 2D spin-glass state below 12 K.

Lithium diffusion channels activate above 125 K.

Li-ion hopping rate follows Arrhenius behavior with Ea=100 meV.

Abstract

We have studied low-temperature magnetic properties as well as high-temperature lithium ion diffusion in the battery cathode materials LixNi1/3Co1/3Mn1/3O2 by the use of muon spin rotation/relaxation. Our data reveal that the samples enter into a 2D spin-glass state below TSG=12 K. We further show that lithium diffusion channels become active for T>Tdiff=125 K where the Li-ion hopping-rate [nu(T)] starts to increase exponentially. Further, nu(T) is found to fit very well to an Arrhenius type equation and the activation energy for the diffusion process is extracted as Ea=100 meV.