An extensive implementation of electric and hybrid-electric propulsion is one of the ambitions of the European Commission to achieve a sustainable aviation. Current mature developments of electric aircraft are using architectures with battery packs, with the Pipistrel Velis Electro being the first electric aircraft, and still the only one in the world, to receive full type-certification. In addition, aircraft structures are inspected in scheduled maintenance on ground, while early detection of overstress of the structure during flight can reduce the sizing factors for damage tolerance and ease inspections. Addressing the previous topics, multifunctional structural batteries satisfy three functions simultaneously: energy storage, monitoring electrical and structural performance, and loads bearing. This technology can reduce weight penalty compared to conventional batteries and improve the health monitoring of the structure. MATISSE project implements this technology in an aeronautic component, i.e. a composite wingtip of a light aircraft, reaching a technology readiness level (TRL) 4 in 2025 by performing full-scale ground structural and functional tests. This paper will overview how smart structural batteries can contribute to reducing emissions and make electric and hybrid-electric aircraft more efficient.