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Chemistry

How Electrochemical Impedance Spectroscopy Characterizes Battery Degradation in Lithium-Ion Cells

Quick fact

EIS can measure the resistance of a battery's internal layers in milliseconds, and a single scan can detect whether the battery is aging due to a thickening Solid-Electrolyte Interphase (SEI) or due to loss of active lithium.

Why this is interesting

Your phone's battery slowly loses its ability to hold a charge, but what exactly is happening inside? Electrochemical impedance spectroscopy (EIS) can reveal the internal changes without taking the battery apart.