Fraunhofer EMI's X-ray System Films Inside Battery Cells at up to 1,000 Images per Second
The high-speed imaging system is being developed with PowerCo for industrial use and scheduled for installation in 2028.
Fraunhofer EMI has developed a high-speed X-ray system that visualizes what happens inside large-format prismatic battery cells under load in real time, working with Volkswagen Group's battery cell manufacturer PowerCo to bring the technology into industrial use.
What Happened
The Fraunhofer Institute for High-Speed Dynamics (EMI) paired X-ray imaging with a purpose-built battery test chamber and sensor systems that simultaneously capture temperature, pressure, voltage and gas flow. The system records up to 1,000 images per second, revealing gas formation, material displacement and crack propagation inside cells. A protective chamber shields the X-ray components from conditions generated during lithium-ion cell thermal runaway—a capability Fraunhofer EMI calls a key engineering milestone. Cell manufacturers and vehicle integrators have previously relied on simulation, destructive testing and indirect measurement to understand what occurs inside failing cells. The partners say initial results are feeding into development of production cells at PowerCo, with the system scheduled for installation at PowerCo's Salzgitter site in 2028.
Why It Matters
For battery engineers and automakers, direct observation of internal cell processes has been largely impossible without destroying the cell. The ability to capture thermal runaway dynamics at high resolution could inform safer cell designs and improve simulation models used across the industry. For EV buyers, better understanding of how cells behave under stress may eventually translate into more reliable battery packs. PowerCo CTO HW Vassen said the technology allows optimization of battery cell safety and design in a highly targeted way.
The Bottom Line
Fraunhofer EMI and PowerCo are moving toward industrial deployment of a system that for the first time makes dynamic processes inside battery cells visible in real time at high resolution. The modular platform is designed to scale across different cell formats and new chemistries as both partners advance their development work.
