Computation of Madelung Energies for Ionic Crystals of Variable Stoichiometries and Mixed Valencies and their application in Lithium-ion battery voltage modelling

TL;DR

This paper introduces a new Ewald-based method to compute Madelung energies in ionic crystals with variable compositions, and applies it to model lithium-ion battery voltages with spinel cathodes.

Contribution

A novel computational approach for electrostatic energies in ionic crystals with mixed valencies, applied to lithium-ion battery voltage modeling.

Findings

Method effectively computes Madelung energies for complex ionic structures.

Application successfully models lithium-ion battery voltages.

Advantages over existing methods are discussed.

Abstract

Electrostatic energy (Madelung energy) is a major constituent of the cohesive energy of ionic crystals. Several physicochemical properties of these materials depend on the response of their electrostatic energy to a variety of applied thermal, electrical and mechanical stresses. In the present study, a method has been developed based on Ewalds technique, to compute the electrostatic energy arising from ion-ion interactions in ionic crystals like LixMn2O4 with variable stoichiometries and mixed valencies. An interesting application of this method in computing the voltages of lithium ion batteries employing spinel cathodes is presented for the first time. The advantages of the present method of computation over existing methods are also discussed.