Scientists at University of Oxford in England, have exposed a ‘secret ingredient’ inside lithium-ion batteries. This material has always been there, of course. We just could not detect the hidden binders in lithium-ion batteries before. We discover how the researchers achieved this, and what this means for battery science.
The Role of Hidden Lithium-Ion Binders
The polymer binder – for that’s what it is – plays a key role in keeping the negative anode electrode intact. And yet, quite amazingly, this polymer material that accepts and releases ions only contributes 5% of battery weight.
A University of Oxford article on Sci Tech Daily explains how binders influence mechanical strength, and electrical and ionic conductivity too. As well as overall battery lifespan, which is a critical factor from a user perspective.
Battery scientists have previously had difficulty tracing just where those hidden binders in lithium-ion batteries are. This is because the binders lack distinctive features, and are only present in small quantities.
This relative obscurity makes it harder for battery scientists to fine-tune lithium-ion chemistry performance. This matters, because the exact location of the binders affects electro-chemical conductivity, structural stability, and durability over time.
How The Invisible Binders Became Visible
The University of Oxford team developed a novel way to stain the binders, and have applied for a patent. Their procedure attaches traceable silver and bromine markers to widely used cellulose- and latex-based binders, in graphite- and silicon-based anodes.
These binders then become visible under energy-dispersive X-ray spectroscopy, because they emit characteristic X-rays. They may also emit signals visible with electron imaging.
“This staining technique opens up an entirely new toolbox for understanding how modern binders behave during electrode manufacturing,” observes lead author Stanislaw Zankowski.
“For the first time, we can accurately see the distribution of these binders, and correlate them with anode performance.”
More Information
Cloning Battery Binders From The Sea
Glue in a Battery That Binds It
Preview Image: Binders on Graphite Particles