To support the upcoming short-term needs of the battery industry, it is imperative to have new differentiating European battery technology for 4b generation batteries on the market from 2025. Halide solid state batteries for ELectric vEhicles aNd Aircrafts (HELENA) responds to the need of the development of a safe, novel high energy efficiency and power density solid state battery (4b generation batteries) cells, based on high capacity Ni-rich cathode (NMC), high-energy Li metal (LiM) anode and Li-ion superionic halide solid electrolyte for application in electric vehicles and, especially in aircrafts. HELENA will support Europe, in this sense, on its transition towards a climate-neutral continent since electric aviation is poised to take off within the next five to 10 years, with innovations already being pursued for electric vehicle batteries. Moreover, HELENA will avoid dependence on Asia for battery production. HELENA is built by a multidisciplinary and highly research experienced consortium that covers the whole battery value chain and proposes a disruptive halide-based solid-state cell technology with the overall aim to significantly increase the adoption of these batteries on aircrafts and EVs The technical challenges that are presented by current conventional battery technology and the consumer needs will be overcome - especially the reduction in costs of battery devices, enable scalable and safe cell manufacturing, increasing their capabilities for long distance traveling and fast charging, ensuring a high safety of the battery.