Breakthrough EV Battery Tester Spots Dangerous Leaks
New technology from INFICON will soon allow automotive manufacturers and battery suppliers to reliably test critically important electric-vehicle battery cells for the first time. INFICON is currently in discussion with several companies to develop robotic and high-speed assembly-line applications for its new leak-detection technology.
Battery-cell leaks 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, according to Thomas Parker, INFICON’s North American automotive sales manager. He expects to see a significant increase in global battery demand over the next 10 years.
Customers also will be expecting lithium-ion batteries to last longer and function properly. It therefore will become critically important to use the most reliable and precise leak-detection devices possible when testing these types of cells.
“Annual lithium-ion battery-cell production in gigawatt hours (GWh) is expected to rise from 280 GWh this year to 2,600 GWh in 2030,” Parker points out. “Customers expect battery cells to function properly for years or even decades without a loss in power or unexpected failures, which will require new standards for in-depth battery-cell testing.”
INFICON’s new 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 facility in Cologne, Germany, they also incorporate sensor technology from INFICON’s North American headquarters in Syracuse, New York.
Dr. Daniel Wetzig, INFICON’s research and development director for leak detection, based in Cologne, notes that only a small fraction of new battery-cell leaks can be detected through traditional methods. He adds that the company’s new ELT3000 technology not only can detect leaks 1,000 times smaller than other test methods, but also could pave the way for the industry’s first reliable quality-control standards for EV battery cells.
The ELT3000 is based on INFICON’s mass-spectrometry technology.
“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 this industry-first spectrometer technology also can help assure an extended EV battery life of up to 10 years or more.”
The mass spectrometer and software used with the ELT3000 are critical to assuring the most precise measurement of leaks. The mass spectrometer is highly sensitive and selective, enabling it to provide reliable and repeatable measurements that follow international metrology standards such as those applied by the National Institute of Standards and Technology (NIST) in the United States or the German Institute of Calibration (DKD – Deutscher Kalibrierdienst). Furthermore, the ELT3000’s simplified user interface provides an exact and correct measurement process even when used by a relatively unskilled operator.
“Every step in the test process, from calibration and determining signal rates up to establishing actual leak rates, is completely automated by our system,” Parker points out. “The user just has to click on start and wait until an answer appears on the display. Ten minutes of operator training is usually sufficient for learning how to use the system on a regular basis.”
The system’s software also automatically stores test results, saving up to 32,000 test results for later analysis. Stored data can be exported easily to other technical devices which significantly helps complete analysis of previous tests. The system also can be equipped with a barcode scanner to assign each battery its test result.
INFICON’s product engineers faced a variety of challenges in the three-year development program for the company’s breakthrough battery-cell leak-detection system.
Issues that were encountered included the need to adapt the system to specific customer requirements, as well as to develop standardized methods for calibrating the system to meet international leak-detection standards.
One of the biggest challenges was the need to develop a process for leak testing pouch cells without damaging the cells in the process. To solve the problem, INFICON used a unique flexible test chamber equipped with a soft foil lining to protect the pouch cells during the test process.
“A vacuum of a few millibars is required in the test chamber to accurately test a lithium-ion pouch cell,” explains Dr. Wetzig. “Since a pouch cell typically cannot resist a vacuum level of this kind, it will burst when tested. We had to develop a special foil membrane which clings to the pouch cell during the testing process to prevent damage to the cell.”
INFICON holds 17 patents for its flexible chamber and has applied for three additional patents to protect its new ELT3000 leak detection technology.
INFICON currently is working with a number of system integrators to adapt its new technology for robotic applications and for use on various types of production lines.
The ELT3000 test process itself is fully automated. INFICON also is developing larger test chambers to accommodate a greater number of cylindrical, prismatic and pouch battery cells at one time.
“We will have larger test chambers available later this year and expect to see automated systems equipped with the ELT3000 in service during the first quarter of 2021,” Parker notes.
INFICON’s new technology is available for use in research and development laboratories and also can be combined with a variety of automation technologies that make it suitable for use on high-speed assembly lines.
For more information: www.inficonautomotive.com