Elucidating the evolution of silicon anodes in lithium based batteries

Silicon has attracted particular attention as a potential high capacity material for lithium based batteries. However, the application of Si-based electrodes remains challenging, in major part due to its significant irreversible energy loss during cycling. Here isothermal microcalorimetry (IMC) is demonstrated to be a precise and operando characterization method for tracking a battery’s thermal behaviour and deconvoluting the contributions from electrochemical polarization, entropy change, and parasitic reactions. Cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and x-ray powder diffraction (XRD) further elucidate the Si reactivity in conjunction with the IMC.