Electrochemomechanical Properties of Red Phosphorus with Lithium, Sodium and Potassium

Abstract

Red phosphorus is a promising anode material thanks to its ability to form alloys with lithium, sodium and potassium, thus achieving high theoretical capacity (2596 mAh g-1 with Li and Na and 865 mAh g-1 with K). However, it suffers from its low electronic conductivity and a huge volume expansion that leads to the formation of stress with consequent fracture and pulverization of the particle. In this work, red phosphorus particles have been analyzed with in-situ TEM techniques in order to study the mechanism of the crack formation during the volume expansion with lithium, sodium and potassium. This experiment is coupled with computational modelling of the particles and the simulation of the diffusion of the ions through the particles to understand the development of stresses that can lead to the nucleation of the crack and the failure of the particle.