Abstract:The power utilization and functional reliability of wireless charging system are important issues of concern. In order to obtain flexible inductance coil with high elastic stretchability and low resistance, the design idea of multi-strand interconnect is proposed. First, the electrical properties and elastic stretchability of multi-strand serpentine interconnect and single-strand serpentine interconnect are comparatively studied, and the advantages of the multi-strand serpentine interconnect are proved. Then, the effects of wire thickness, length of straight segment, radius of arc and central angle on the electrical properties and elastic stretchability of serpentine interconnect are investigated. The results show that the length of the straight segment, the central angle and radius of arc are sensitive parameters affecting the elastic stretchability of serpentine interconnect. Finally, the sensitive parameters affecting the elastic stretchability and resistance of serpentine interconnect are optimized by orthogonal experiment. The resistance of the optimized flexible and stretchability coil is reduced by 13.5% and the elastic stretchability is increased by 34.3%. The research results provide theoretical guidance for optimal design of flexible and stretchable wireless charging coil.