New technology from INFICON soon will allow automakers and battery suppliers to reliably test critically important electric-vehicle battery cells for the first time.
Faulty battery cells can dramatically shorten battery life, increase warranty costs, affect customer satisfaction and damage product reputation, as well as create safety-and-drivability problems.
Billions of lithium-ion battery cells are produced annually for use in electric, hybrid-electric and autonomous vehicles, as well as for medical devices and a variety of consumer electronics products. Depending on cell type, five percent or more of those cells may have undetected leaks.
INFICON's breakthrough leak-detection systems can reliably and accurately test all types of lithium-ion battery cells for the first time – the single most important leak-detection development in the past 10 years. Developed at the company's research facilities in Cologne, Germany, they also incorporate sensor technology from INFICON's North American headquarters in Syracuse, New York.
Based on mass-spectrometer technology, the company's new leak detectors are able to identify dangerous leaks 1,000 times smaller than currently possible, says a press release.
Dr. Daniel Wetzig, INFICON's research and development director for leak detection based in Cologne, notes that only a fraction of new battery-cell leaks can be detected through traditional methods. He adds that the company's new ELT3000 technology also could pave the way for the industry's first reliable quality-control standards for EV battery cells.
“The rapid detection of even the smallest battery-cell leaks is absolutely essential to achieving extended service life and meeting necessary safety requirements," Wetzig says. "The use of industry-first spectrometer technology, for example, can help assure an extended EV battery life of up to 10 years or more."
Wetzig points out that INFICON's new systems also can be used to test billions of battery cells annually produced for use in smartphones, computers, and other consumer electronics products.
Three types of battery cells today are used to power most hybrid-electric, electric, and autonomous vehicles:
hard-cased prismatic, cylindrical cells and softer pouch cells. INFICON equipment for testing prismatic and cylindrical cells is scheduled for introduction in October, followed by testing devices for pouch cells in late 2020 or early 2021.
Empty hard-case battery cells currently are checked by filling the cells with helium test gas to detect leaks while in a vacuum chamber. Electrolytes are not inserted into the cells until after they have been "dry tested."
Helium bombing is an alternative approach, but generally not suited for liquid-filled components. If used, however, electrolyte-filled battery cells are placed in a vacuum chamber and exposed to helium under pressure. Helium enters through existing leaks and then can be measured as it escapes back into the vacuum chamber.
Neither test method provides the reliably consistent results needed to establish industry-wide standards for battery-cell leak detection.
INFICON's new process will, for the first time, allow automakers and battery suppliers to accurately test battery cells already filled with electrolyte. The cells are placed into a vacuum chamber connected to an INFICON ELT3000 leak-detection unit with a mass spectrometer for testing.