Source: Energy & Management Powernews, January 06, 2022
Lithium-ion batteries lose storage capacity over time. As recent research shows, however, this process can be revised.
Researchers at the renowned Stanford University and the US government SLAC National Accelerator Laboratory have found a way to extend the life of lithium-ion batteries by up to 30%.
Behind the age-related loss of capacity of lithium-ion energy storage devices is the effect that, over time, zones of inactive lithium form in the cells that no longer have electrical contact with the electrodes. Researchers in the USA have now succeeded in moving these "islands" in the direction of an electrode and thus making them usable again for energy storage.
The movement of the lithium islands was made possible by a combination of a regular charging process and an extremely rapid discharge of the cells with a high current density. The researchers had previously noticed that the seemingly "dead" lithium regions actually move back and forth a little during charging and discharging processes - but on the scale of nanometers.
"We realized that we could move the inactive regions toward the anode during discharge, and that the higher the currents involved, the better this works," explains Fang Liu, lead author of a study on the topic. Simulations confirmed the findings, and tests with a test cell showed an increase in the usable lifetime of the cell by about 30 %.
The researchers are confident that integrating their findings into charging management could, for example, increase the lifetime of electric car batteries.
Author: Peter Koller