The SSiON-ACSENT project seeks to advance sodium-ion battery (SIB) technology by addressing key challenges such as limited lifespan, low energy density, and slow charging rates. By developing high-performance anode and cathode architectures incorporating single-atom catalysts (SACs) on MXene, metal-organic frameworks (MOFs), and bio-derived carbon, the project aims to significantly enhance battery performance. These SACs, through precise d-orbital tuning and heteroatom coordination, improve metal ion adsorption and conversion kinetics, thereby boosting overall battery performance. The anticipated outcomes align with the European Commission's ambitious climate strategy, targeting climate neutrality by 2050 while reducing dependence on critical raw materials. SIBs, leveraging sodium's abundance and environmental benefits, represent a sustainable alternative to lithium-ion batteries (LIBs). Pre-commercial SIBs have demonstrated energy densities around 160 Wh/kg, but SSiON-ACSENT aims to raise this range to 200-350 Wh/kg (an increase of 25-118%), with an improved cycle life of 5000-8000 cycles (a 25-100% improvement) and enhanced safety. By integrating SACs into 3D porous structures, the project focuses on improving Na-ion intercalation, optimizing electrode-electrolyte interfaces, and accelerating ion transport, overcoming the current limitations of SIB technology. This research directly supports the Horizon Europe mission for affordable, clean energy and aligns with the European Green Deal and MSCA Green Charter by promoting sustainability and responsible consumption. The innovations within the project contribute to advancing energy storage solutions and transitioning toward sustainable energy systems.