Lithium-ion batteries are widely used, but accurate estimationLithium-ion batteries are widely used, but accurate estimationof their state of charge and state of health is still an open issue.Integrating chemical and physical sensor data with electrical measurementscan improve the estimation algorithms and foster the early detectionof destructive failures. One-dimensional dilatometry systems basedon the eddy currents principle represent low-cost and promising solutionsto measure the dilation of the cells caused by charging operations andhealth degradation phenomena. These systems are based on a simpleinductance-to-digital converter that measures the inductance of a PCBcoil to evaluate the distance between the coil and a target. These devicesrequire an accurate design since the coil sizing strongly influences themeasurement accuracy. This work aims to optimize the design of the coilconsidering different parameters, notably the shape, the trace width, andthe internal filling of the spiral.

Keywords: {Eddy-currents, Lithium-ion batteries, PCB coils, sensor fusion,Eddy-currents, Lithium-ion batteries, PCB coils, sensor fusion,state of charge}