Researchers at Stanford University have discovered a technique to revive the lithium clusters that form in lithium-ion batteries. This allows them to increase their lifespan and restore the capacity that has been lost during the recharging cycles.
One of the biggest problems with electronic devicesis at the level of autonomy, which decreases over time. In the as the discharge and recharge cycles progress, the piles are formed reducing the capacity of the accumulator and creating a risk of and of .
In an article published in, researchers at Stanford University wanted to better understand the functioning of these isolated lithium « islands » and therefore built a transparent in order to observe them. They discovered that these clusters are not completely inactive. One side is dissolved, while the other of the is filed. They therefore move very slowly towards one or the other of the during charge and discharge cycles.
A rapid discharge to reconnect the isolated lithium
This displacement was found to be faster with a higher current. The researchers therefore added a rapid discharge step directly after the end of a charge cycle. This allowed the isolated lithium to be displaced enough to reconnect it to the. The cluster is then reactivated and participates again in the charge cycle of the accumulator. In the laboratory, the experimental saw its life extended by 30%.
According to the researchers, the technique could be applied to current accumulators, prolonging their life and increasing the autonomy of devices whose batteries are starting to run low. It could also remove the main obstacle to the development of, whose capacity is ten times that of but whose metallic lithium anode disintegrates over time.