Batch diagnosis of batteries within one second
Shangwei Zhou, Wenjia Du, Bastian Mager, Paul R. Shearing, Thomas S. Miller, Rhodri Jervis
Abstract
As demand grows for scalable and sustainable energy storage, fast and affordable diagnostics are urgently needed, especially for factory-level cell sorting and second-life assessments. Electrochemical impedance spectroscopy (EIS) is widely used but remains too slow, complex, and costly for large-scale use. This work introduces a multi-channel and multi-frequency electrical excitation response (MMER) technique that captures comparable impedance-related information at a fraction of the time and cost. MMER can diagnose entire battery modules in 1 s, regardless of cell count. It uses a binary multi-frequency excitation signal, implemented on simple hardware such as programmable logic devices. Unlike EIS, MMER avoids frequency-domain transformation and impedance fitting. Instead, it compares raw voltage responses under a shared excitation current to reveal performance variations. Experiments show MMER tracks cell health in line with EIS while reducing test time by over 99%. It supports real-time diagnostics even during high-rate cycling and extends to other electrochemical systems.