Electrochemical impedance spectroscopy investigation on battery materials using a symmetrical cell

Various works have been carried out on lithium-ion batteries for improving the different conductivities of electrode materials. For this purpose, electrochemical impedance spectroscopy is a technique choice to understand elementary processes that take place during charge/discharge steps and quantify their respective contribution in total impedance. However, some materials, such as lithium iron phosphate (LFP), suffer from poor electronic conductivity high interfacial resistance when used with standard aluminum current collector. In article, influence both temperature pressure LFP response reported order provide an accurate description interface detailed analysis time constants observed response. This was made possible through use carbon-coated Al collector decrease contact impedance, development four-electrode symmetrical coin cell setup allows insertion mechanism be studied function state charge single battery, i.e., without need build battery each SOC studied.