“HELIOS” is an acronym for High-performance modular battery packs for sustainable urban electromobility services. The HELIOS project funded by the EU Commission under Horizon2020 aims to create a new concept of hybrid, modular and scalable battery pack for a wide range of use cases, to be adapted for improved EV range and/or fast charging time according to different use cases, combining high-energy and high-power cells to achieve ambitious goals. Applying a holistic approach, the HELIOS project investigates optimal eco-designs and advanced processes to demonstrate innovative, lighter and eco-friendly EV battery packs as effective models for urban electromobility, and in addition facilitates the reuse in 2nd - life energy storage applications and easier recycling at its End of Life, contributing to a circular and sustainable supply chain in the EU.