A finite-strain chemo-electro-mechanical model for gel polymer electrolytes with dynamic ion exchange between fluid and polymer phases

Climate change pivots on shifting to renewable energy sources and to reliable, readily available energy storage systems; at present, lithium-ion batteries (LiBs) are the most advanced industrial technology. Great efforts towards novel materials are underway to overcome well known safety concerns in conventional liquid electrolytes. Gel polymer electrolytes (GPEs) are promising candidates. They are composed of a fluid mixture that fills the interstitial spaces in a solid polymer network. The confined liquid boosts the conductivity and improves the surface contact with electrodes. We devise a multiphysics model for GPEs, framed in the finite-strains thermo-mechanics of continua. It accounts for the electro-chemistry, transport, and mechanics of energy storage. Predictive science is achieved through simulations of the transport and chemical interactions of solvent and ions during material advection. Insightful information on the behavior of GPE during charge–discharge of (Li-ion) batteries are attained. • 3D multiphysics model developed for gel polymer electrolytes (GPEs). • Coupling of electrochemical, transport, and mechanical effects considered. • Finite-strain mechanics and thermodynamic consistency incorporated. • Dynamic ion exchange between polymer- and solvent-coordinated states modeled. • Numerical simulations show how operating conditions impact ion transport and mechanics of GPEs.