The iSTORMY project will propose an innovative and interoperable hybrid stationary energy storage system based on: modular battery pack (stacks/modules) + modular power electronics (PE) interface + universal Self-healing energy management strategy (SH-EMS). In particular the project will investigate and demonstrate: 1. Modular battery pack with hybridization at stacks/modules level (incl. slave pBMS) with a new universal BMS (adaptive interfaces + accurate SoX) at the top of the battery system for easy and fast integration and control. The hybridization will consist of different battery types or same type with different capacities (first and second life) and a smart modular solution will be developed to integrate the cooling system among modules or stacks. 2. Modular PE interface based on SiC devices with high efficiency (topology + adaptive local controller) and Digital Twin modeling. 3. Universal SH-EMS (based on machine learning and online algorithms) including the aging and thermal constraints for failure mechanisms.