Energy storage technologies will likely play a key role in achieving society's decarbonization goals. Lithium-ion batteries are widely used for mobile energy storage applications today due to rapid reductions in their cost achieved over the past decade. However, concerns about volatility in the cost of their constituent materials has driven a search for alternative technologies, particularly for stationary grid storage applications, for which cost is a key consideration. Batteries based on the redox of multivalent cations (e.g. Mg 2+ , Ca 2+ , Zn 2+ , or Al 3+ ) represent promising alternatives in this regard due to the abundance of these elements, potential safety advantages, and the potential for increased energy density associated with multi-electron redox reactions. Arguably the most significant challenge impeding the adoption of these batteries is the sluggish mobility of multivalent ions in solids. Identifying materials with sufficiently high multivalent ionic conductivity to serve as either solid electrodes or solid electrolytes has proven challenging, though experimental and computational studies have identified anti-perovskites and chalcogenide • This work • Muy et al. • Krauskopf et al. Cation-sublattice interactions relate these properties via intermediate observables, while previous studies have reported direct correlations. (b) Low-frequency vibrational modes exhibit a greater probability P (x) of far-from-equilibrium displacements upon thermal excitation than high-frequency modes. V (x) denotes the potential as a function of displacement.