Structurally integrated battery strategies for short-range all-electric aircraft: A feasibility and trade-off analysis

Kurzfassung

The commercial feasibility of short-range, battery-electric passenger aircraft is primarily limited by the low energy density of current and future battery technologies. This issue is escalated by the substantial gravimetric penalties of conventional battery packaging, which reduce effective system-level energy density. This study therefore investigates the integration of batteries distributed throughout the aircraft's structure for a reference regional aircraft with a maximum take-off mass (MTOW) of 23 tons, targeting a mission range of 1476 km, which corresponds to an onboard energy demand of 10.21 MWh. Three integration strategies were evaluated: complete structural pouch-cell integration, partial structural module integration and conventional battery pack installa tion. The results show that, even with projected 2035 battery technologies, the conventional approach results in a prohibitive battery mass of 45.4 tons, which is nearly twice the aircraft's maximum take-off weight (MTOW), resulting in an infeasible configuration at the aircraft level. In contrast, full structural integration reduces the required battery mass by 57%, to 19.4 tons, significantly narrowing the remaining feasibility gap. While the mission requirements remain challenging, the results demonstrate that structural battery integration represents a key enabling technology for achieving aircraft-level feasibility, bridging a substantial portion of the feasibility gap that conventional packaging concepts are not able to close. Furthermore, a multi-objective optimization of the electric power system shows that structural integration enables wing-only energy storage, leading to an optimized 848 kg, 3 kV DC radial distribution architecture by minimizing cabling mass and electrical losses compared to fuselage-based storage concepts. These findings highlight that battery placement and electrical system architecture are strongly coupled design variables and must be considered jointly in the conceptual design of viable electric aircraft configurations.