The project has three vertical objectives:

• exploring and advancing a non-conventional semi-solid-state Li-ion battery material formulation suit-able for structural batteries: NMC622 (cathode), Si/C (anode) and bicontinuous polymer-ionic liquid electrolyte (BCE), i.e. NMC622|BCE|Si/C;

• enabling the functional integration of this material within the CCF and RMS concepts, upscaling them to the level of a representative aeronautic stiffened panel structure, i.e. SOLIFLY demonstrator;

• characterising the electrochemical and mechanical performance of this demonstrator.

These vertical objectives are complemented with a horizontal one: to tailor SOLIFLY to the needs of the aeronautic industry. This is achieved by factoring end-user requirements and specifications into the design process right from the start, and by including airworthiness and manufacturing criteria together with a technology roadmap and TRL scale-up strategy. The SOLIFLY demonstrator aims at achieving a gravimetric energy density at cell level between 100 and 180 Wh/kg, a nominal discharge rate of 1C, being capable of sustaining 300+ cycles at 0.1C with 90% capacity retention and achieving TRL 4 by the end of the project (2023).

SOLIFLY ultimately aims at supporting the long-term development of the European aeronautic industry, delivering the first aeronautic stiffened panel with an integrated semi-solid-state battery, and paving the way for making structural batteries a viable technology for the next generation hybrid electric airliner.