Recycled Ni–Zn ferrite magnetised asphalt mixtures: electromagnetic and functional performance for wireless charging pavements

Inductive charging pavements for electric vehicles are limited by pavement electromagnetic properties. This study develops a magnetised asphalt mixture (MAM) using recycled Ni–Zn ferrite as fine-aggregate replacement and evaluates its performance in an 85.5 kHz S–S compensated wireless power transfer system from experiments and simulations. Ferrite incorporation increases effective relative permeability (μeff) up to ∼21.84, while efficiency saturates around μeff ≈ 13. A minimum MAM thickness is required for net efficiency gain across studied gaps, with a maximum gain of ∼10.4% over a conventional mixture. Under lateral misalignment (i.e. horizontal offset between the transmitter and receiver coil centres, DS = 60 mm), MAM mitigates efficiency loss, increasing coupling coefficient and efficiency by ∼0.06 and 2.4%. A permeability window μeff ≈ 7–13 is recommended, and a 1 km WPT lane can reduce annual input energy by ∼2.3 × 104 kWh and CO2 emissions by ∼10 tons.