Increased prevalence of energy storage at a system level for vehicle, aviation and stationary storage applications depend on safe and robust design from cell level components and power electronics materials, through to modeling, system design and suppressants. Complex off-normal events involving liquid, mist and vapor flammable chemicals, electrodes and casings, as well as ancillary power electronics have required understanding potential failures and design ways of mitigating their risk and severity. Modeling and empirical studies of the use of containment for failed systems, in addition to suppressant selection and application are all heavily reliant on better materials understanding at every level of design for energy storage. Without compromising on cost or form factor, more inherently safe electrochemical storage must be developed, and integration must be done using engineered safety with a deep understanding of risk and failure propagation. Current experimental and theoretical approaches to materials safety of energy storage of single material components, or cell level assembly are also critical to building in resilient energy storage. The effect of off-normal conditions such as internal short, external overcharge or over temperature for example provide another aspect critical to understanding materials properties and effects on cell to system resilience and safety.