It has always been tempting to assume what goes on inside a battery is completely static. Well, except for those zillions of ions whirring back and forth, but do such tiny things really count. Scientists from Argonne National Laboratory shifted that paradigm, when they used a cutting-edge x-ray tool to peer inside operating cells. You got it, they spotted tiny movements inside lithium battery cells!
Lithium Battery Components Making Tiny Movements
“It’s really exciting to be able to visualize these movements,” says Daniel Abraham, senior materials scientist at Argonne. The Chemical Sciences and Engineering Division’s study author continues, “Other researchers have previously guessed these movements happen. But they’ve not been able to show them in such fine detail.”
The study author’s team set out to understand two challenges holding lithium-ion battery progress back.
- In the first instance, how these batteries swell and shrink during charging and recharging.
- And in the second, why detrimental materials accumulate on the lithium battery anode.
This video is an actual, real-time view of tiny movements they saw inside lithium battery cells, when they peered inside an operating battery:
The Particular Focus of the Argonne Research
The Argonne team viewed tiny movements of the anode, the cathode, and the separator, inside an operating battery cell. Now the separator is a porous layer between the electrodes that prevents them touching.
They already understood how lithium ions deposit on the anode during charging, which then expands. And how the process reverses during discharge. However, they now have a better understanding of how a residual, permanent coating accumulates, shortening the battery’s calendar life.
EurekAlert reviewed the research and commented, “The X-ray technique has other valuable applications. It can identify if the expanding battery components are compressing the separator too much.
“This compression can cause the separator’s pores to close, slowing down or even stopping the movement of lithium ions between the electrodes. It can also be used to determine lithium concentration gradients in the cathode.”
More Information
Short Circuiting a Battery: What Happens Next
Battery Chemistry and What It Is All About
Preview Image: Iions Move in Battery
