After an on-board fire grounded a Boeing 787 Dreamliner at Heathrow Airport in 2013, a safety review was put into action of all lithium battery-powered equipment on planes.
The incident inspired a a team of researchers led by University College London, which has now been able to track, in real time, how disposable Lithium batteries degrade during normal use. The team employed 3D imaging techniques, offering a novel, non-invasive method of monitoring performance loss and help guide the development of better commercial battery designs.
The team recently used the same technique to show how rechargeable Lithium-ion batteries fail when they are exposed to extreme levels of heat, but this is the first time the extent of day-to-day damage of disposable Lithium batteries has been shown.
The fire on the Boeing 787 Dreamliner 2013 incident was caused by the plane’s disposable Lithium battery-powered emergency locator transmitter which sends out a radar signal to locate missing aircraft. Although the system is designed to keep working until the aircraft is found, the results show that the batteries may not be quite that resilient.
To display the internal structural damage caused to batteries working under normal conditions in real-time, the team used X-ray imaging techniques and tracked different types of wear-and-tear, which contribute to performance loss. The team linked this wear to design features of the commercial battery.
“On the outside, the batteries look like they are doing their job normally but inside we saw the structure was undergoing great change. Electrical activity was high in some areas of the cell, whereas it was low in others; layers of electrode material separated and cracked. All of these changes in structure affect the flow of electricity and reduce the performance of the cell,” said Donal Finegan, UCL PhD student and first author on the study.
Real-time 3D images of active commercial Li/MnO2 disposable batteries were captured using X-ray computed tomography (CT) and advanced digital volume correlation software. From the images, the team formed cross-section time-lapse videos displaying the damage that occurred to the electrodes inside the battery in real-time.
“Lithium disposable batteries are used for mission-critical systems where recharging is impractical, so understanding the safety and reliability of them is important, particularly given recent high-profile cases where batteries on aircraft have failed,” said Dr. Paul Shearing, corresponding author on the study from UCL. “We gained valuable insights that apply to a variety of commercial batteries using this system, showing an effective, non-invasive way for industry to monitor performance and improvements in commercial battery design.”
By mapping the activity and strain on the material inside the battery, the team hopes to help manufacturers predict how long a battery will perform.
Story via University College London.
Comments are closed, but trackbacks and pingbacks are open.