Fraunhofer EMI, together with battery manufacturer PowerCo (Volkswagen Group), has developed a high-speed X-ray imaging system that lets engineers observe internal dynamic processes in large-format prismatic lithium-ion cells in real time, a capability previously unavailable to cell developers and integrators who have had to rely on simulation, post-mortem teardown or indirect sensing. The setup pairs high-performance X-ray hardware with a purpose-built battery test chamber and synchronized sensors for temperature, pressure, voltage and gas flow, capturing up to 1,000 frames per second. This resolution is sufficient to track gas generation, internal material displacement and crack propagation as they occur during cell operation and failure.
A significant engineering challenge was designing a protective housing capable of shielding the X-ray components from the extreme thermal and mechanical conditions produced during thermal runaway events. Fraunhofer EMI has already applied the system with several German OEMs, including VW and Audi, to study material ejection during runaway and propagation across multicell arrangements, generating data that supports both cell design evaluation and refinement of simulation models for development and certification work.
Fraunhofer EMI and PowerCo are now moving the system toward industrial deployment. Early findings are already informing PowerCo's production cell development, and the system is planned for installation at PowerCo's Salzgitter site in 2028. It is built as a modular platform, intended to accommodate different cell formats and future chemistries.
Source: Automotive Testing Technology International — read the original article