Linking battery electrode science with correlated and quantum materials

Quantum materials are highly sensitive to electron count and electronic structure. While these properties are usually established during synthesis, electrochemistry provides a way to modify them after synthesis, continuously and reversibly at room temperature.

In transition-metal oxides, Li⁺ and Na⁺ insertion and removal change the electron count of the transition metals, providing an electrochemical control over spin state, charge ordering, electron localization, magnetism, and electronic conductivity.

This connection is particularly important because battery electrodes are themselves strongly correlated materials. The localized d electrons and on-site Coulomb interactions described by the Hubbard U directly influence their redox chemistry and electrochemical potentials. Battery electrodes therefore provide a practical example of how electronic correlations govern materials behavior—and electrochemistry provides a means of tuning those correlated states.

Battery electrodes can therefore serve as electrochemically tunable quantum materials—and as a platform for testing the theories used to describe correlated electrons.

The Hubbard U directly influences calculated battery-electrode redox potentials.

Electrochemical (de)insertion drives Li_xCoO₂ through distinct electronic and magnetic states.

The electronic phase diagram of Li_xCoO₂.

You can read more in our perspective article in APS Physical Review Materials.