By focusing on the way lithium moves between 2 electrodes, scientists in Netherlands have come up with latest new battery design that promises much faster charging rates. The architecture incorporates specialized channel structures that enable a greater flow of lithium-ions, which the team hopes can help improve grid storage capability of renewable-energy.
The research was administered by scientists at the University of Twente and focuses on a comparatively new class of materials called niobium tungsten oxides (NbWO). These are seen as promising candidates to replace graphite used because the negative electrodes in today’s lithium-ion batteries, as they permit lithium ions to flow through them at much greater rates.
In 2018 a study from the University of Cambridge during which scientists developed and tested A battery with large pillar-like particles of NbWO, which allowed lithium ions to travel in larger quantities and with greater freedom. The University of Twente team has taken a special approach, exploring what happens when these particles are reduced to the nanoscale size.
The team approached this by calcinating NbWO, or heating it to high temperatures in an oven, to produce tiny nanoparticles measuring tens or many of hundreds nanometers in size. One among the features of those nanoparticles is ability to conduct lithium ions at their boundaries, in effect creating lots of more exits for them to require as travel through battery.
Through its testing, team found that these downsized, nanostructured particles performed impressively, writing, “the results demonstrate that downscaling below 100 nanometers significantly enhances the lithiation dynamics of niobium tungsten oxide. Furthermore, it suggests that grain boundaries of Nb18W16O93 have significant influence to the fast lithiation process.”
While the results are promising, the team sees technology finding serving specific uses, at least to start with. Design would not be suitable for electric cars, the researchers note, because it would require too big A battery pack. Where it could prove valuable, however, is in some “peak shaving” scenarios, where an over- or under-abundance of grid energy from renewable sources requires batteries to be discharged or charged quickly assist or help to manage the load.
The scientists see other possibilities in using technology for batteries that power heavy machinery, except for now are working to fine tune the electrode by investigating its optimal size.