Batteries are notoriously difficult to analyze. Yet, we rely on them for powering technological innovations and for harnessing alternative energy sources. For example, how would we know how long the battery in our electric car will live? How can the company be sure they are giving their customers good cells? These are questions that are surprisingly difficult to answer.
Now, NYU Chemistry Professor Alexej Jerschow and researchers at the University of Mainz and the Helmholtz Institute Mainz, Germany developed a technique based on atomic magnetometry that allows scanning batteries and determining their state of charge and state of health, and producing images that depict the distributions of charges storage of the device. The technique works by using atomic magnetometer sensors, which are some of the most sensitive magnetic field measuring devices. These sensors pick up the magnetic fields produced by the components in the battery and are shown to depend on the state of the device. In addition, the technique allows measuring the tiny electrical currents within the battery cells. This is information that is currently impossible to obtain in any other way, and could help in designing next-generation battery cells. .
The research was published in PNAS, and picked up by Scientific American. NYU Chemistry authors include graduate student Mohaddese Mohammadi and postdoctoral fellow Emilia Silletta in the Jerschow Lab.
Click here to read the PNAS article, "Sensitive magnetometry reveals inhomogeneities in charge storage and weak transient internal currents in Li-ion cells."
Click here to read the Scientific American article, "Ultrasensitive Fuel Gages Could Improve Electric Vehicle Batteries."
This research was funded in part by the National Science Foundation.