Published on February 21st, 2017 | by Tina Casey0
OSU Stakes Claim To World’s First Hydronium Ion Energy Storage System
February 21st, 2017 by Tina Casey
A research team at Oregon State University is very excited over their new energy storage system, and not just because it is the world’s first hydronium-ion battery. They’re also excited because the new device provides a way forward to the next generation of grid scale stationary batteries that will enable the US grid to accommodate more solar and wind power.
So, A Proton Walked Into A Bar…
A hydronium ion (H3O+) is what happens when you add a proton to a water molecule. They have been the object of much study these days, partly because of their emerging importance in battery systems.
Here’s an explainer from our friends over at Quirky Science:
…the water molecule allows acids to ionize. This is possible because of the formation of the hydronium ion. This is of immense importance not only to the physical properties of the universe, but to life itself.
Okay so that’s a little over the top but QS provides a hint why energy storage researchers are so interested in hydronium:
While the hydronium ion contains the hydrogen ion in its structure, the hydronium ion itself is surrounded by yet more water molecules. This serves to spread the positive charge further, stabilizing the system to a greater extent. The number of molecules associated with a given hydronium ion can range from perhaps six to many more than a dozen.
First Energy Storage Device With Hydronium Ions
In the new energy storage breakthrough, the OSU team created a rechargeable battery with hydronium ions as the charge carriers.
The break with conventional energy storage devices is a big one. Until now, positively charged ions that are used in batteries have belonged to the metals family.
The electrode which stores the hydronium ions is made of PTCDA, short for perylenetetracarboxylic dianhydridem. That sounds exotic but it’s basically just a solid crystalline material with a lattice structure, in the class of organics (think: plastic, not metal).
OSU explains why PTCDA was selected for the new battery:
…PTCDA material has a lot of internal space between its molecule constituents so it provides an opportunity for storing big ions and good capacity.
The hydronium ions also migrate through the electrode structure with comparatively low “friction,” which translates to high power.
Here’s chemist Xiulei Ji of OSU enthusing over the potentials:
“This may provide a paradigm-shifting opportunity for more sustainable batteries…It doesn’t use lithium or sodium or potassium to carry the charge, and just uses acid as the electrolyte. There’s a huge natural abundance of acid so it’s highly renewable and sustainable.”
What’s Next For The World’s First Hydronium-Ion Battery
Okay, so don’t hold your breath to hang one of these hydronium batteries on your wall à la Tesla’s Powerwall.
So far the OSU team has been able to confirm that the new energy storage system works in the lab by measuring the dilation of the PTCDA structure.
On the bright side, foundational research does make it out of the lab, eventually, if everything works out.
You can get more details from the German science journal Angewandte, which published the team’s study under the title “Hydronium-Ion Batteries with Perylenetetracarboxylic Dianhydride Crystals as an Electrode.”
Here’s what “measuring the dilation of the PTCDA structure” looks like in the study’s abstract:
…hydronium ions can be reversibly inserted into and extracted from 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA). The expansion and contraction of the PTCDA lattice correspond to H3O+ intercalation and deintercalation, respectively, as revealed by ex situ XRD studies and density functional calculations.
Speaking of Tesla, the OSU team is pretty certain that the Tesla Gigafactory will not have to be retooled to churn out hydronium batteries for electric vehicles some day, but Tesla’s Elon Musk might want to start planning ahead when it comes to stationary energy storage.
According to Ji, the new technology provides a way forward to develop sustainable energy storage alternatives, especially at the grid end of the scale.
That’s a mighty help in this age of rapid climate change, which underscores the point of last Sunday’s Rally for Science in Boston: science is a good thing.
If you’re keeping track of the numbers, the Rally for Science probably did not attract quite as big a crowd as President Trump’s 2020 campaign kickoff rally (yes the 2020 campaign is a thing), which attracted 9,000 fans in the safety of an airplane hangar in Florida last Saturday night.
However, when you consider the turnout for the Not My President’s Day rallies taking place all over the US just two days later, 9,000 is pretty small potatoes.
And then there’s that whole thing going on regarding a presidential visit to London but hey, who’s counting?
Image (screenshot): Simulated PTCDA unit cell via Oregon State University.