Electrochemical energy storage is critical for a range of applications spanning electrified transportation and grid energy storage. Lithium-based chemistries have been favored for their high energy and power-densities but require precise management to prevent premature degradation and catastrophic failure. Despite battery chemistry improvements and increasingly tight manufacturing tolerances, there remains significant concern about failure of a battery after it leaves the factory and enters the field. Therefore, large-scale battery systems require a battery management system, responsible for battery state monitoring and power management for safe operation. This work aims to improve state-of-the-art battery management by transferring the gold-standard in laboratory battery diagnostics from the laboratory to the field. These diagnostic capabilities, based on electrochemical impedance spectroscopy (EIS), enable insight into the internal electrochemical processes of a battery through frequency response measurements. This work replaces traditional linear amplifier-based EIS with a power electronics platform to reduce system cost, size, and energy requirements.