The project SILMARILION aims at demonstrating a set of battery components suitable for 700Wh/L cell, using the following full cell level approach: -New cation-deficient Li-rich positives, targeting a specific capacity >= 250mAh/g -µm-size Silicon from low cost milling, blended with graphite to achieve an electrode with > 1000mAh/g -screening of electrolyte components and assess interface with active materials -focus on electrode formulation in order to determine the more suitable set of binders and conductive additives -correlate the complete cell properties to active materials & interfaces ageing, thanks to advanced characterization techniques such as NMR and EELS (i.e. highlight the importance of full cell configuration vs half-cell). -Demonstrate the achievements at prototype level with 3 generations of 18650-like cells, in order to reach a durability target of 20% energy loss after 1000 cycles at C/2 at room temperature and 20% energy loss after 400 cycles at 45°C. -explore some power/energy ratios.