ABQ Times

Batteries in electric vehicles can fail rapidly, sometimes resulting in fires without much warning. Sandia National Laboratories is working to address this issue by detecting these failures earlier and providing sufficient warning time for vehicle occupants.

Sandia's research on detecting battery failures sooner was published in the Journal of the Electrochemical Society. The current systems in electric vehicles detect performance issues with lithium-ion batteries but do not focus on imminent safety concerns.

“The nature of battery fires can vary widely, depending on the failure mode. Some batteries self-heat for hours, while others are abrupt and aggressive,” said Alex Bates from Sandia’s battery safety group. “The battery starts heating uncontrollably, ultimately resulting in a fire.”

Battery management systems currently measure temperature and voltage, which are lagging indicators of safety issues. This means warnings may come too late when a fire is imminent or already occurring.

“We’re focused on extending the warning time,” stated Loraine Torres-Castro, Sandia’s battery safety lead. “Our aim is for the diagnostic system to provide an early warning, allowing time to park safely and exit the vehicle.” She noted that integrating this system into car dashboards is the ultimate goal.

At Sandia's Battery Abuse Testing Laboratory (BATLab), commercial off-the-shelf diagnostics are being tested on single cells and battery packs to identify methods for early detection of failures before they catch fire.

“Our objective is to benchmark commercially available solutions for different failures that exhibit varying responses and require tailored diagnostics,” Torres-Castro explained. “One size does not fit all. We seek to identify specific tools that can provide early warnings for particular failure conditions, battery chemistries and cell engineering.”

Sandia's unique expertise supports this work due to their understanding of material science, electrochemistry, engineering, and how batteries fail.

“It’s important work. Industry is interested in this space," Bates said about their published paper that has started conversations around battery safety for electric vehicles.

The research also has implications beyond vehicle batteries; it's being evaluated for potential use in grid energy storage systems with large batteries.

Looking ahead, there remains significant work to do on detecting electric vehicle battery failures more quickly.

“The next phase is understanding the limitations and applying machine learning algorithms to datasets,” Bates mentioned. Another focus area involves advancing sensor technology so they can activate mitigation measures upon receiving warnings.

As part of future steps, Sandia will test disassembled cells from electric vehicle battery packs at different scales to check current market diagnostics' limitations.

“It’s very exciting to be at the forefront of practical battery safety," Torres-Castro expressed about their ongoing work.

Bates added his enthusiasm by saying, “We’re always excited about the science.”