(Invited) Computationally Guided Design of Sustainable Chemistry for Low-Cost Battery Technologies

The ever-growing demand for storing electrical energy generated from intermittent source of renewable energy (e.g., sun, wind etc.) has necessitated development of new low-cost, safe, and sustainable battery systems that go beyond the conventional Li-ion technology. In this context, electrochemistry based on aluminum and iron – third and fourth most abundant elements on earth, respectively – offer the most promise. Unfortunately, long-standing issues with electrolyte design, cyclability, dendrite proliferation, and parasitic side-reactions has precluded deployment of rechargeable Al- or Fe- batteries. Most of the daunting issues stalling progress stem from dearth of atomic-scale understanding of solvation chemistry, ion-transport, chemical reactions, and material evolution in the bulk electrolyte, as well as electrode/electrolyte interfaces. In this talk, I will demonstrate how a synergistic integration of first-principles calculations, ab initio /classical reactive molecular dynamics simulations, electrochemical experiments, and spectroscopic measurements can pave the path towards advancing such understanding; and accelerate design of low-cost battery technologies. Specifically, I will showcase two recent successes of this approach, which led to (a) design of low-cost, fire-resistant inorganic molten-salt electrolytes containing Al n Cl 3n+1 – species, which allow fast de-solvation of Al 3+ ions and prevent dendrite formation – both central for fast-charging Al-chalcogen batteries (200 C) with high cycle life, and (b) demonstration of a novel bi-directional Fe(OH) 2 /FeOOH redox chemistry facilitated by sulfate intercalation in Fe(OH) 2 , which drastically impairs parasitic hydrogen evolution, and Fe 3 O 4 formation – consequently, enhancing capacity and cycle life of alkaline batteries. I will discuss these results in the context of accelerating design of new sustainable high-performance battery technologies for grid-storage.