Tuesday, February 10, 2009

EEStor's Promise

We have reported extensively on the EEStor ultra capacitor battery here, but also have made no particular note of the scope that the technology holds for improvement. The technology relies on producing a matrix of small spheres of active material coated with aluminum and held together in an active binder. The fine details, we do not know and they are not at this point our business.

But we can say something. They targeted a particle size able to provide sufficient energy density to store enough energy to drive a light electric vehicle a distance of 300 kms.

This implies that any improvement in particle size will improve energy density by the cube of the magnitude of its improvement.

It appears reasonable that a first generation improvement could well produce a device that is superior by a factor of ten through one thousand. This is a huge upside. It also suggests that the potential for the technology is almost unlimited, or at least until we hit the real bounds of the particle protocol. They may have started at the technical limits although none of us believe that.

A thousand-fold improvement, which I suspect is feasible, is a revolution in energy storage.

The point is that improvement is merely an improvement in particle size. That is a rather believable research target. The rest is surely troublesome but likely very achievable.

So we all have a lot riding on EEStor’s energy storage technology.

A next generation overcomes the current issue of vehicle weight, just as the first generation overcomes the issue of vehicle range. I must imagine that a third generation will overcome the issue of power for long haul trucking and heavy equipment.

No other energy storage technology holds this promise. It would be nice to have information on what the theoretical limits actually are. You can be sure that we will eventually test them.


DGDanforth said...

I believe that the particle size of the dielectric only weakly determines the energy density of the EESU. One of their patent diagrams shows 31,000 cells (this is from my memory) with each cell having a metal top and bottom and the dielectric sandwiched between. If the plate separation remains constant but the particle size decrease (and hence more particles are inserted) then the stored energy should be (approximately) unchanged since the energy is in the electrons stored on the metal plates (and also some in the polarization of the dielectric). If you completely removed the dielectric and replaced it with a vacuum the energy density should again be (approximately) unchanged. I believe (but could be convinced I am wrong) that the dielectric is solely for the support and insulation of the metal plates. If the dielectric were "pure" and could support a electric dipole (like little magnets) then the particles against the top plate would almost be touching the plate BUT their particles are surrounded by aluminum oxide (I believe)to act as an insulator so no charge can leak from the dipole inside the particle to the plate. The particle's dipole acts (kind of) like an reverse image of the plate charge which helps to hold the plate charge firmly fixed (neighbor electrons on the plate don't see the charge of an electron since it becomes shielded (slightly) by the dipole field of the dielectric. This allows more electrons to be crammed onto the plate for a given voltage.

So it is my contention that your factor of 1,000 is not correct. Its more subtle than that.
Best regards,

arclein said...


The material i had suggested that the dielectric was central to the process, but explanations were certainly obscure. Your exp-lanation takes us back to a more conventional setup.

I must admit that I tossed this out in order to get more clarity on the tech.

Also, I suspect something clever is brewing up here, otherwise why bother with the whole particle sizing issue and the particular coating type?

I wonder if the plates are etched?

ADVILL said...

What DGDanforth says is true, as a matter of fact EESTOR device violates some Physics law at least as it is now (which is quite possible in a time when there are leads that Second law of Termodynamics is not as it is..).

Esstor, if true will put things upside down in relation with the smart grid, low energy electrolysis of MIT Dr. Noceda is the other fundamental change that will move most of the energy to electricity.

arclein said...

I am far too familiar with the art of misdirection to take anything produced to date as serious. For a fact they are working with micron and nano sized coated spheres.

that is a creditable hint that is likely important.

After that we have to reinvent and we will be offtrack immediately.

The fact that lockheed has patented a flexible battery layer hardly supports metal layers.

So something is going on here that we do not grasp.

Or this could all be an exercise in creative hooey, except who is the victim? I still remember star wars and knew that to be government sponsored hooey then.

Tom Villars said...

EEStor's patent actually claims 300 miles on a 52 kWh EESU, not 300 km.

"The energy-storage unit must supply 52,220 Wh or 10,444 W for 5 hours to sustain this speed and energy usage and during this period the EV will have traveled 300 miles."

EmeryKO said...

As in all engineered products it looks like some trade offs are being made to build this device. One needs a plastic ink printer with a working fluid that will generate void-less uniform dielectric layers that not susceptible to dielectric breakdown under high potential fields. What tradeoffs in plastic types were made? What are the trade offs of particle size and scouring of the printer mechanism or printer jamming? The particles require a bonding agent to allow the ceramic particles to be “wetted out” by the plastic medium. What size is the optimum for bonding to the plastic with least affects to the permittivity of the completed dielectric? All these tradeoffs have to be evaluated and managed to produce a uniform working product.

EmeryKO said...

Of concern is also device failure methodology that constrains the operational environment, device lifetime and degradation characteristics. For example, semiconductor devices lifetimes track closely to the operation time and operating temperature, greater temperature reducing the device lifetime. In space and to a lesser extent on the ground cosmic ray bombardment generates ion trails through devices with some failing quickly and others surviving; marginally effected by the radiation. An ultra capacitor needs an inherent limit current or cascading current flow from cosmic particle damage may cause immediate catastrophic failure. Tradeoffs in conductor and dielectric form and performance characteristics must be evaluated to quench a microscopic over current condition.