Breakthrough Technology Reveals Internal Battery Dynamics
The Fraunhofer Institute for High-Speed Dynamics (Fraunhofer EMI) and PowerCo, the battery manufacturing arm of Volkswagen Group, have collaboratively developed a high-speed X-ray imaging system. This system can capture up to 1,000 images per second, allowing researchers to observe in real time the internal processes of large-format prismatic battery cells under load. For the first time, critical phenomena such as gas formation, material displacement, and crack propagation inside batteries can be directly monitored, offering unprecedented insights for enhancing battery safety and performance.
Sebastian Schopferer, a battery safety expert at Fraunhofer EMI, stated that the system can reveal internal changes within a failing battery cell at the highest resolution in fractions of a second, fundamentally transforming how battery design and safety are assessed. He noted that previously, researchers relied on simulations or destructive testing to infer internal battery conditions, whereas this system provides the capability for direct observation.
Protective Chamber Ensures Stable Operation Under Extreme Conditions
To address the high temperatures and pressures generated during lithium-ion battery thermal runaway, Fraunhofer EMI developed a specialized protective chamber. This chamber effectively isolates X-ray components from extreme conditions, ensuring the system remains operational even during battery failure events. This design is regarded as a key engineering milestone in the system’s development, enabling researchers to safely observe battery behavior under extreme stress.
The system integrates multiple sensors that simultaneously record temperature, pressure, voltage, and gas flow data during testing, providing comprehensive monitoring capabilities. This data not only aids in evaluating battery design safety but also improves existing simulation models, enhancing battery efficiency and reliability.
System Already Applied in Automotive Testing, Set for Deployment at Production Site in 2028
Fraunhofer EMI disclosed that the high-speed X-ray system has already been utilized in battery testing for several German automakers, including Volkswagen and Audi. The research team used the system to analyze material ejection during thermal runaway and failure propagation in multi-cell configurations. The resulting data has been applied to assess battery design safety and refine the accuracy of simulation models.
Under a collaboration agreement, Fraunhofer EMI and PowerCo will deploy the system at PowerCo’s production site in Salzgitter, Germany, by 2028. Fraunhofer EMI will contribute material research, battery abuse testing, and high-speed imaging technology, while PowerCo will provide production requirements and actual battery samples. Both parties confirmed that initial test results are already being integrated into PowerCo’s production cell development process.
HW Vassen, Chief Technology Officer of PowerCo, emphasized that the system allows dynamic processes inside battery cells to be visualized in real time and slow motion for the first time, offering unprecedented depth of insight. He stated that this technology will significantly accelerate the optimization of battery safety and design, driving the industrial adoption of innovative solutions. Fraunhofer EMI and PowerCo describe the system as a modular platform scalable to different battery formats and new cell chemistries, laying the foundation for future advancements in battery technology.
