News | New technologies | Energies
By listening to the sounds emitted by batteries, researchers have been able to improve battery charge cycles, enhance functional safety, and control post-manufacturing quality without altering the batteries.
Researchers at Liten, a CEA Tech
institute, equipped batteries with acoustic sensors to listen to the ultrasound
they emit (between 100 kHz and 300 kHz) during operation. Their work involved
not only NiMH but also lithium-ion and NiZn batteries.
The researchers discovered that outgassing
at the electrodes increased the acoustic emissions of nickel batteries as they
reached full charge. This is crucial information that battery management systems
(BMS) could use to ensure more effective charging throughout a battery’s lifetime.
The technique can also prevent thermal runaway in lithium batteries—a common phenomenon
that we can now “hear.” This discovery could help make batteries much safer.
In addition, when
charged for the first time, a lithium-ion battery creates a passivation layer,
which partly determines the battery’s service life. Until now manufacturers
have used empirical techniques for this process as there is no non-destructive
way of measuring the layer. This research could soon help manufacturers produce
higher quality batteries by using sound to monitor the formation of the passivation
layer without altering the battery.
CEA is a French government-funded technological research organisation in four main areas: low-carbon energies, defense and security, information technologies and health technologies. A prominent player in the European Research Area, it is involved in setting up collaborative projects with many partners around the world.