EASA Special Condition E-19 (SC E-19) is the European certification framework specifically targeting electric and hybrid-electric propulsion systems, including the battery energy storage systems (BESS) used for primary aircraft propulsion. SC E-19 is currently the most directly applicable European certification standard for high-power propulsion battery packs in eVTOL and regional electric aircraft.
SC E-19 defines requirements covering: battery system design and architecture; thermal management; thermal runaway detection, propagation prevention and containment; failure mode and effects analysis (FMEA); crew warning and protection systems; and installation safety margins. It applies to battery systems forming part of the propulsion unit and is used alongside CS-E (Engines), CS-25 and the relevant environmental qualification standards.
References: EASA Special Condition SC E-19 (official document page)
See also: DO-311A, 14 CFR Part 25