Electrolytes and cathode designs for next generation of silicon‐based batteries – Comprehensive experimental and computational considerations

Abstract

AbstractThe increasing demand for energy storage technologies has prompted the exploration of side‐by‐side technologies, that can complement the current Lithium‐ion battery industry with cheaper and more abundant materials that can be incorporated in a myriad of new electrochemical cell designs. To meet these goals, a novel approach for electrolyte design using quantum‐mechanical density function theory (DFT) modeling was implemented in concert with experimental electrochemical characterization to culminate in a predictive model that can be tailored to a specific cell chemistry. Physical characteristics as dielectric constant, solvent acidity, basicity etc. influence fluoride speciation, solvation and electrolyte performance, in an iterative fashion to enable characterization prediction of 19F NMR shifts, ionic conductivity mechanisms and fluoride reactivity in a myriad of liquid phase organic solvent. Herein, Silicon (Si) anode batteries were constructed with fluoride‐based electrolytes to yield optimal ionic conductivity, adequate anode surface activation, current density and electrochemical stability with corresponding cell characterization and operation mechanism. Our novel and functional tools enable optimal utilization of active Si anode‐based batteries with complementary advanced cathode materials, bringing forth the next generation of electrochemical energy storage systems based on an active Si anode.