Doc Brown Would Be Proud (Part 1 of 2)

From the People, Planet, Profits & Projects Blog by Richard Maltzman, Dave Shirley

Most of you are probably familiar with Dr. Emmett Brown.  That’s a photo of him at the top of this post. He is not a famous psychologist from the University of Chicago, nor is he the leading cardiologist at the Boston Medical Center.  He doesn’t even have a PMP(R) credential, and he’s not even a real doctor.  Well, he is a real doctor character, the ‘mad scientist’ in Back To the Future, played eloquently by Christopher Lloyd.

And he uses an interesting device to power his Delorean electric vehicle: a flux capacitor.

See the sign below.  Watch out!

Of course, there is no such thing.

Or… is there?

I have encountered two recent articles which, while not using the term “flux capacitor” are using the term “supercapacitor”.  The articles are not from science fiction magazines, either, they are from IEEE Spectrum and from New Scientist.

To me, the irony of the story is very sweet, because this is about using two ancient materials – concrete and carbon – to create capacitors which can be built into the environment to power houses and potentially vehicles.

Here’s the paragraph that got my attention – in an article from New Scientist magazine, August 2023:

A mixture of cement and charcoal powder could enable houses to store a full day’s worth of energy in their concrete foundations. This new way of creating a supercapacitor – an alternative to batteries that can discharge energy much faster – could be incorporated into the foundations of both buildings and wind turbines. When paired with renewable energy sources, it could also someday let concrete road foundations wirelessly recharge electric vehicles as they drive along.

This is striking in several ways, not the least of which is the idea that the power source for homes, businesses and vehicles could be built into the environment, which smacks of the whole concept of The Built Environment, for which PMI now is offering a credential (the PMI-CP™).  Indeed, I am working with industry professionals and academics to work this into our curriculum at Boston University.

The Supercapacitor

But let’s get back to this supercapacitor – the project that led to its development and the projects it will undoubtedly launch – projects that would make Dr. Emmett Brown quite proud.

Here’s an image of the supercapacitor in the lab (courtesy of IEEE Spectrum):

Let’s start with the ingredients.  This is another irony.  To power the modern world in an environmentally-responsible manner, requires the generation and storage of electricity without the need for fossil fuels, without hazardous or rare-earth chemicals (like those used in batteries).  You would think that some brand-new whiz-kid material would be invented to do that.  Not so.  One of the main ingredients in this supercapacitor is carbon black.  To give you an idea of how new this material is – it was used to write the Dead Sea scrolls.  So: not new.  The other material is concrete, also ancient.

The trick is in the surface area.

To make the material for their supercapacitor, the team at MIT (see story here) stirred up a paste made of cement and water, and then introduced carbon black, a fine, charcoal-like form of carbon which is highly conductive, into the paste.

As this cement mixture cured, the water was absorbed, and when evaporated, left behind a veinous network of tunnels when ended up being filled by the carbon black.

The resulting material is now a latticework … with a large surface area of conductive, winding, branching tunnels, without expanding the overall volume of the material, which can now serve as an electrode for the capacitor.

The Capacitor

I suppose I should digress here for a moment and tell those who don’t have an electrical engineering background about capacitors.

There is controversy over who developed the first capacitor, and there’s even controversy over the invention of the predecessor of the capacitor, the Leiden (or Leyden) jar. This was invented nearly simultaneously by German cleric E. Georg von Kleist, but was followed up with more research and intent by  by Pieter van Musschenbroek at the University of Leiden in the Netherlands in approximately 1745.  In effect, they layers of foil separated by an insulator (called a dielectric).  You can see them in action in this video:

 they are classically represented by this symbol, a quite logical one, two plates separated by a gap (air, glass, plastic, or other dielectric).

As current (excuse the pun) electronic components, they often look like one of these:

However, now, the concept of this small electronic component , with this innovation, is expanded into the very construction material itself.

In part 2, I will continue with the possible implementation ideas for this technology.


MIT article

New Scientist article

IEEE Spectrum article