A low-cost approach to on-board electrochemical impedance spectroscopy for a lithium-ion battery

Abstract

In this work, we describe the design and the implementation of a low-cost acquisition system for electrochemical impedance spectroscopy for on-board applications. The proof of concept is based on a commercial battery monitor for lithium-ion batteries and a system-on-chip control unit, which can also be used to control other devices, like a stimulus generation unit. The acquisition system frequency range is 0.1–500 Hz, bringing the commercial device to its highest performance limits with low costs. We evaluate the acquisition system performance through the measurement repeatability and accuracy, making some statistical tests validated against data obtained through a laboratory spectroscopy instrumentation. In order to show the operation of the acquisition system within a complete spectrum analyser for on-board application, we embody a sinusoidal stimulus generator in a proof of concept, integrating in an easy way its control strategy into the acquisition system control unit. Such a generator is obtained by changing the control system of a commercial battery charger.