Battery degradation-aware vehicle routing problem for heterogeneous electric vertical takeoff and landing aircraft delivery fleets

With the rapid development of the low-altitude economy, electric vertical takeoff and landing aircraft are increasingly deployed in urban logistics delivery. As a critical component, the degradation of the health state of lithium-ion batteries significantly impacts both performance and operational costs of the aircraft. However, existing research rarely integrates battery degradation into route planning strategies, which can result in excessive battery degradation and increased maintenance costs. To address this issue, this study develops a battery degradation-aware vehicle route planning model for heterogeneous delivery fleets to achieve balanced battery resource management. A battery degradation model is developed utilizing a real-world battery aging dataset, and a weighted average plane interpolation method is employed to linearize the proposed model. Furthermore, a mixed-integer linear programming model is formulated to minimize the total health degradation of the fleet while satisfying energy consumption and payload constraints. Through this primary optimization objective, the model indirectly extends the remaining useful life of the fleet and reduces maintenance costs. The computational study demonstrates the superiority of the proposed route planning model over traditional shortest distance-based optimization methods. In instances of varying-sized experiment groups, the average battery degradation per kilometre was reduced by 40.41 %, the average remaining useful life of the fleet was extended by 53.26 %, and the average maintenance and operational costs per kilometre was decreased by 37.32 %. Sensitivity analysis further reveals that the benefits of the proposed route planning model become increasingly pronounced as the initial health state approaches the failure threshold.