MARS-EV aims to overcome the ageing phenomenon in Li-ion cells by focusing on the development of high-energy electrode materials (250 Wh/kg at cell level) via sustainable scaled-up synthesis and safe electrolyte systems with improved cycle life (> 3000 cycles at 100%DOD). Through industrial prototype cell assembly and testing coupled with modelling MARS-EV will improve the understanding of the ageing behaviour at the electrode and system levels. Finally, it will address a full life cycle assessment of the developed technology.MARS-EV proposal has six objectives:(i) synthesis of novel nano-structured, high voltage cathodes (Mn, Co and Ni phosphates and low-cobalt, Li-rich NMC) and high capacity anodes (Silicon alloys and interconversion oxides);(ii) development of green and safe, electrolyte chemistries, including ionic liquids, with high performance even at ambient and sub-ambient temperature, as well as electrolyte additives for safe high voltage cathode operation;(iii) investigation of the peculiar electrolyte properties and their interactions with anode and cathode materials;(iv) understanding the ageing and degradation processes with the support of modelling, in order to improve the electrode and electrolyte properties and, thus, their reciprocal interactions and their effects on battery lifetime;(v) realization of up to B5 format pre-industrial pouch cells with optimized electrode and electrolyte components and eco-designed durable packaging; and(vi) boost EU cell and battery manufacturers via the development of economic viable and technologically feasible advanced materials and processes, realization of high-energy, ageing-resistant, easily recyclable cells.MARS-EV brings together partners with complementary skills and expertise, including industry covering the complete chain from active materials suppliers to cell and battery manufacturers, thus ensuring that developments in MARS-EV will directly improve European battery production capacities.