# Supercapacitor storage bank ?



## Karter2 (Nov 17, 2011)

Sorry if this product has been raised before, i searched and nothing came up.
Kilowattlabs Sirius Supercapacitor storage "battery "
Several of the other forums ..Solar, EV, tech , etc...are having some debates over the Sirius product which claims to be the first Supercapacitor based storage device for use with Solar systems, utility storage, EVs, RVs etc etc
They claim it can replace any current Lead ,AGM, or Lithium, battery function.
Infact the list of claims are extensive, not least being rapid charge/discharge, 99% efficiency, million cycle life with no capacity reduction, totally fire safe (non combustable materials) , and $1/Wh price point.
http://www.ultraflexgroup.com/en/ca...capacitors-energy-storage-systems.html?lang=2
Note they are initially offering 3.5kWh and 7.1 kWh , units with other sizes and voltages to follow.
Obviously if any of this is true, then storage has truely advanced instantly, but as many of us realise, these claims go beyond any current proven Supercap performance abilities.....hence why there is hot discussion raging.
Some of you may already be involved in those discussions on other forums , but my reason for raising it here is to rais awareness to either help prove/disprove the validity of this device such that we either can avoid it or benefit from its technology.


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## brian_ (Feb 7, 2017)

It's at least a bit amusing that Uflex didn't both to translate some (but only some) of the terms from Italian to English, and list three characteristics of the communications port ("TCP/IP", "RJ45", and "ETHERNET" as if they are three different communications methods, one for each model.

Something doesn't add up to me, based on the minimal description from Uflex:

Is is just a pile of capacitors? Then a small range of voltage would not use the capacity effectively.
Is it fronted by a DC-DC converter? Then the 99% efficiency and "no heat dissipation. No need cooling or ventilation" claims are nonsense.

The manufacturer is Kilowatt Labs, not Uflex. Their website claims a 100% depth of discharge, which is not possible in practical terms (since a fully discharged capacitor is at zero volts), but suggests that the capacitor voltage is taken very low, so the power conditioning must include a DC-to-DC converter.

This is the entirety of the EV section of their Storage Applications page:


> *Electric Vehicles*
> 
> Bringing Instant Mobility to the Electric Vehicle Industry.
> 
> ...


So a 30 kWh battery would weigh 261 kg... so this isn't a leap forward in energy density by mass; the advantages would be in power density (especially for charging) and cycle life.

I have no idea who they think will be reading this that would think that the number of wheels on a vehicle would change whether or not it can use this type of energy storage. 

Self-discharge has always been an issue with capacitors, and this product actually includes a small lithium ion battery to compensate, so it's definitely still an issue:


> A charge retention circuit controls a small percentage of embedded Li Ion to supply current to reduce charge leakage and increase self-discharge time to 14 days.


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## Karter2 (Nov 17, 2011)

There is a video on this page with the Australian distributor.
Half way through he talks about the Supercap pack and even shows what he claims is one of the supercaps used.
He also mentions that the "cell" capacity will double and triple in the next versions !...which implies a big improvement in the energy density. (Which is already beyond current known supercap levels ?)
Note also the claims of fire safety, and 45 yr design life !
http://www.cleanenergy.org.au/renew...arvios-super-capacitor-energy-storage-system/


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## Duncan (Dec 8, 2008)

_So a 30 kWh battery would weigh 261 kg... so this isn't a leap forward in energy density by mass_

I heard 75 kg for a 3.5 kwh unit so 640 kg for 30 kwh

Not impressive for batteries - but for supercaps that is about 50 times better than existing units

I have contacted them and I got

_Hello Duncan
We are excited about this product but we don’t have all of the pricing and specifications through yet. I will let you know when we do.
Regards
Jason_

When I do hear back I will pass it on 

These are roughly 1000th the price of existing supercaps - I hope it's not just somebody getting his number wrong


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## ishiwgao (May 5, 2011)

Duncan said:


> _So a 30 kWh battery would weigh 261 kg... so this isn't a leap forward in energy density by mass_
> 
> I heard 75 kg for a 3.5 kwh unit so 640 kg for 30 kwh
> 
> ...


I know Skeleton Technology is aiming for a 20Wh/kg supercap by 2020 (https://chargedevs.com/newswire/ske...pacitors-targets-heavy-transportation-market/), and so this would still be about 6x heavier (1500kg for 30kWh) than the one from KiloWatt Labs.

I'm a bit skeptical about the 115Wh/kg supercap spec. I think someone probably missed a period "." somewhere, or mixed up their supercap spec with a battery spec lol.

In terms of pricing, well even if they're an order off, it's still cheap for supercaps


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## Karter2 (Nov 17, 2011)

Pack Shorting test video posted by Arvio on the aussie EV forum..
...comments ?
https://youtu.be/LflfpqBTwnQ


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## Duncan (Dec 8, 2008)

Hi Karter

They have a module - but I'm not sure what they expect those tests to show - they are not testing the supercaps - just the electronics that control the caps

I would be much more interested if they took the lid off to have a look inside 

The total power capacity would be interesting as well - but at the loads it's designed for NOT a short

At least it shows that the units do exist and are not total vapourware

Still no update from the salesman who promised me some specs


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## Karter2 (Nov 17, 2011)

This post was just put up on the Aussie EV forum site, in reply to many requests for information and proof that this is not just a disguised Lithium pack.
The author is Paul Wilson of Arvio the importer of the Sirius battery in Au


> Post by Supercaps » Today, 18:26
> 
> Start by reading the patent that was published yesterday. Just for clarification there is no in series dc to dc conversion and no electrochemical cells despite Richo’s determined effort. We fly these units on planes regularly at 40 x the allowable Wh limit of lithium ion electrochemical batteries. There is no riddle. No trick. Always open to a visit at our business from anyone who is curious about how it’s done, and yes you can see inside it. Over 100 systems are being installed over the coming months. Many of them will be on line for all to see.


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## Tony Bogs (Apr 12, 2014)

Video of a representative or maybe even owner, seems credible enough.
And he admits that the biggest challenge is making people believe that the product is genuine.

https://www.youtube.com/watch?v=3K8JIC-ov_Y


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## brian_ (Feb 7, 2017)

Karter2 said:


> This post was just put up on the Aussie EV forum site...
> The author is Paul Wilson of Arvio the importer of the Sirius battery in Au
> 
> 
> ...


So, they are using only a small fraction of the capacitor energy capacity, by operating them over a narrow voltage range?

Anyone citing a patent should provide the patent number (and of course issuing country); otherwise, it just looks like a bluff, assuming no one will actually look it up.


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## Karter2 (Nov 17, 2011)

.....the latest post from P Wilson (Arvio)


> There are 1200 x 3,000F super capacitors. 2.7V each. 20 in series and 30 in parallel per layer x 2 layers.


 Note also in his previous post, he claim that they are airfreighting these Sirius units , so someone must have signed a legal declaration to confirm there is no significant lithium ion content in the device. .
Do the FAA physically check to confirm the declaration, before allowing freight to fly ?
But if its not true...someone will go to jail eventually !

Bottom line is, they are claiming to have a 3000F supercap the size of an 18650 cell !. 
.....how likely is that ?
.....


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## Tony Bogs (Apr 12, 2014)

Karter2 said:


> Bottom line is, they are claiming to have a 3000F supercap the size of an 18650 cell !.
> .....how likely is that ?


It;s amazing. Just as amazing as the 1 and 10F when they first became available.

So let's turn it around.
About four/five years ago, graphene hit the news sites as a big promise for storage.
With that in mind I'd say it's certainly not unlikely that in these supercaps the promise has become a reality. 
So far I haven't seen hard evidence that undermines the claims.


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## brian_ (Feb 7, 2017)

Karter2 said:


> .....the latest post from P Wilson (Arvio)
> 
> 
> > There are 1200 x 3,000F super capacitors. 2.7V each. 20 in series and 30 in parallel per layer x 2 layers.
> ...


That's the operating voltage of Eaton's XL60 product, announced in 2016; however, the XL60 cells are much larger than an 18650 - 60 mm in diameter - and have a capacitance of 166 F. A module containing 18 of them (standing vertically in a 3x6 array) is 177 mm high, 420 mm long, and 196 mm high. That's 166 F, not 3,000 F, so the claim here is 20 times greater capacitance in a small fraction of the volume.

Energy storage in a capacitor is 1/2CV**2, so charging a single capacitor of 3,000F would store 
0.5*3000*2.7**2
=10,935 J or 3.04 Wh

Then a set of 1200 would store 13,122 kJ or 3645 Wh, matching the 3.7 kWh claim... but would have to be fully discharged to zero volts to extract that energy. Something does not make sense here.


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## Tony Bogs (Apr 12, 2014)

2.7V is an ordinary value for a supercap. It does not mean anything in relation to Eaton or any other brand.



> Something does not make sense here.


I don't see the smoking gun.

And it is a cap, so discharging is a linear proces, unlike chemical storage. Not a direct drop-in replacement for Li-ion in an EV.


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## brian_ (Feb 7, 2017)

Tony Bogs said:


> 2.7V is an ordinary value for a supercap. It does not mean anything in relation to Eaton or any other brand.


I didn't say or even suggest that these were the Eaton product; in fact, the huge size difference confirms that they are not the same. This was a comparison of capacity - a massive improvement on the order of a factor of 100 - as I explicitly stated.



Tony Bogs said:


> And it is a cap, so discharging is a linear proces, unlike chemical storage.


What doesn't make sense is a claim of capacity that could only be achieved by fully discharging to zero voltage... because, as mentioned above, the relationship of voltage to state of charge is completely unlike an electrochemical cell.

Restoring the critical and omitted context:


brian_ said:


> Then a set of 1200 would store 13,122 kJ or 3645 Wh, matching the 3.7 kWh claim... but would have to be fully discharged to zero volts to extract that energy. Something does not make sense here.


With no voltage conversion component (as also claimed), an energy store with output dropping to zero is not usable.


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## Duncan (Dec 8, 2008)

75 kg - and it contains 1200 off 3000F capacitors
(if the 75 kg I remember was right) 
That gives 62.5 gms/capacitor 

Less than that

In the video he was claiming that their "secret source" was to do with - enabling slow charging and re-charging
And
having the capacitors all balance properly

Those were the improvements that their company had made 

I could be wrong but I don't see either one as an actual problem

The key features to me are the energy/kg and the energy/dollar

And then we get to Brians point - about the voltage change

I really really want to see inside one of these boxes


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## Tony Bogs (Apr 12, 2014)

The key features for me are: 1 million cycles (lower but stiil high at higher amps), wide temperature range, high reliability, no fire hazard.

So I guess the company picked the right application area as their first target for introduction: solar and Australia (outback).


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## Karter2 (Nov 17, 2011)

Tony Bogs said:


> I don't see the smoking gun.
> 
> And it is a cap, so discharging is a linear proces, unlike chemical storage. Not a direct drop-in replacement for Li-ion in an EV.


 Thats the point,... They claim it IS a drop in replacement for any 48v battery.
Its normal operating range being 44-54 volts.
They even have a demo vodeo of the unit powering a industrial electric fork truck.
https://youtu.be/Rm69TFxicfM
Note they also have smaller versions designed as direct replacements for 12v and 24v applications.... (car and truck lead acid replacements)


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## brian_ (Feb 7, 2017)

Karter2 said:


> Thats the point,... They claim it IS a drop in replacement for any 48v battery.
> Its normal operating range being 44-54 volts.


Okay, good catch 

Energy stored by 1200 3000 F capacitors at 54/20 = 2.7 volts:
1200 * 0.5 * 3000 * 2.7**2 = 13,122 kJ or 3.645 kWh

Energy stored by 1200 3000 F capacitors at 44/20 = 2.2 volts:
1200 * 0.5 * 3000 * 2.2**2 = 8,712 kJ or or 2.42 kWh

Net energy available over operating range of 44 V to 54 V:
13,122 kJ - 8,712 kJ = 4410 kJ or 1.225 kWh

(Yes, I know that can be more elegantly expressed as
1200 * 0.5 * 3000 * (2.7**2 - 2.2**2) = 4410 kJ or 1.225 kWh
but I'm not sure that's as clear)

So, can someone explain either what I have missed in my calculations, or how the other 2.4 kWh of stored energy is supposed to be delivered, once the voltage has dropped to 44 volts? How about why +6/-4 volts is an acceptable change from a nominal 48 volts, in competition with a lithium battery?


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## Karter2 (Nov 17, 2011)

Minor point Brian, but he didnt say there was no dc/dc conversion......he actually said there is no "in series". dc/dc conversion !
Now that may be nothing ,..or it may distract from the fact that there could be some cell level conversion trickery,.
That previous photo with the blue supercap bank showed a lot of cell level electronics.
With regards to the voltage range, a typical 48v lithium pack (13 S of 18650s ), would typically have a full capacity range of 39-55volts ( 3v - 4.2v per cell) .


This reminded me of a previous "ultracap" discussion...
Anybody remember the "fastcharge" 1000 hp drag bike thread ?..
http://www.diyelectriccar.com/forums/showthread.php?t=178345&highlight=1000+drag+bike
What happened to that project ?... Their blog is gone and the site is "dusty"


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## Karter2 (Nov 17, 2011)

The Patent..
Surprise !...it contains a " battery array" !!
http://images2.freshpatents.com/imageviewer/20180076644-p20180076644

Thankx to aeva forum.


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## Duncan (Dec 8, 2008)

Wonderful!
In the first video they did mention batteries - but it was something about the supercaps not being able to retain charge for a long time so the batteries somehow fixed that

The core of this is still the super cheap super small supercaps

I do hope that they actually do exist 

I wonder - maybe the 3.6 kWh on the box is the actual storage capacity - BUT with it configured as a battery you can only *use* 1.2 kWh 

Which would tie in with lead acid batteries where you can only use a fraction of the capacity
Or even Lithium where you can only use 80%


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## Karter2 (Nov 17, 2011)

...".And the latest reply from Arvio commenting on the Patent " battery" reference... ????????


> Post by Supercaps » Today, 17:22
> 
> Yes the patent covers this. Patents are normally written as broadly as possible to prevent copying methods by other parties. This is why the words “in some embodiments” and “can” are used. There are no lithium ion electrochemical cells in the super capacitor modules which are being used. Good to see you doing your research. Have you worked out how it’s done yet?...


Suggesting the patent is bit of commercial deception ?


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## brian_ (Feb 7, 2017)

Duncan said:


> In the first video they did mention batteries - but it was something about the supercaps not being able to retain charge for a long time so the batteries somehow fixed that


That's the scheme in which a small battery is used to charge the capacitors as necessary to maintain some minimum level to avoid damaging them. It's not meaningful to storage capacity, but the inclusion of electrochemical cells in a system claimed to have none is disturbing.



Duncan said:


> I wonder - maybe the 3.6 kWh on the box is the actual storage capacity - BUT with it configured as a battery you can only *use* 1.2 kWh


Then the 3.6 kWh claim is meaningless crap. If someone owes you a hundred dollars and gives you a box containing a hundred dollars, but you can only ever actually get ten bucks out of it, does all the extra money in the box do you any good? Do you feel ripped off?



Duncan said:


> Which would tie in with lead acid batteries where you can only use a fraction of the capacity
> Or even Lithium where you can only use 80%


Even a lead-acid battery can be discharged to the full depth of the rated capacity... it costs in cycle life, but the voltage at the end of discharge is still close to the nominal and usable. At even 80% depth of discharge, this "48 volt drop-in replacement" which must be charged to 54 volts to be fully charged is down to 24 volts; that's not useful.


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## brian_ (Feb 7, 2017)

Karter2 said:


> ...".And the latest reply from Arvio commenting on the Patent " battery" reference... ????????
> 
> 
> > Post by Supercaps » Today, 17:22
> ...


Claiming that the design is covered by a patent then sending that "Have you worked out how it’s done yet?" response from Supercaps about the patent would be suitable for someone attempting to insult the recipient as much as possible. 

If I were a potential buyer, I would quite bluntly tell them where to stuff their patents, and to get back to me when they have decided to communicate professionally and prove their claims.

Yes, patents are often filed for any design which can be pushed through the patent processes (which is just about anything now, since patentability no longer requires that the idea be novel, non-obvious, or even workable) and might at any time be used. It's not deceptive, it's just covering all the bases (even possible product names are trademarked although they might be built)... until the company says that the product is as described in patent and then says "gotcha, it's really not".


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## Karter2 (Nov 17, 2011)

OK,.. More feedback from Arvio..


> Post by Supercaps » Today, 01:45
> 
> Just to clarify a few things. The super capacitor in the picture is one of the range of super capacitors, not the one in the 3.55kWh unit. Secondly the calculations are correct except for the micro farad typo. The missing piece of the calculations is understanding of the technique used to extract almost all of the energy from the capacitors from 54VDC down to 44Vdc when in series without a series DC to DC converter. Yes there are electronics involved. The electronics perform high speed balancing between the parallel cell groups. This is the IP of the product. You can learn about this by reading the patent. The real test is at the terminals, which can easily be shown to deliver the energy stated. The unit can be shown opened up to anyone interested in person to have no electrochemical batteries and proven with a colomb meter to be what is stated. Still haven’t had anyone from this thread come to visit. Doors are always open. Nothing to hide......


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## brian_ (Feb 7, 2017)

Karter2 said:


> Minor point Brian, but he didnt say there was no dc/dc conversion......he actually said there is no "in series". dc/dc conversion !


In parallel would make no sense. Weasel words don't give me a lot of faith.



Karter2 said:


> Now that may be nothing ,..or it may distract from the fact that there could be some cell level conversion trickery,.
> That previous photo with the blue supercap bank showed a lot of cell level electronics.


My guess is that's the cell monitoring, and charging (from electrochemical cells!) at extremely low voltage.

I suppose it's also possible that the entire unit is reconfigured to half as many cell in parallel and twice as many in series at the low end of the cell voltage range... but then why not just say that?



Karter2 said:


> With regards to the voltage range, a typical 48v lithium pack (13 S of 18650s ), would typically have a full capacity range of 39-55volts ( 3v - 4.2v per cell) .


Good point, but that full range is not typically used, and the lithium voltage range is much narrower for a very large fraction of the full capacity... and vehicle manufacturers routinely state both a nominal (full voltage range) capacity and a usable capacity.



Karter2 said:


> This reminded me of a previous "ultracap" discussion...
> Anybody remember the "fastcharge" 1000 hp drag bike thread ?..
> http://www.diyelectriccar.com/forums/showthread.php?t=178345&highlight=1000+drag+bike
> What happened to that project ?... Their blog is gone and the site is "dusty"


I skimmed through that discussion... yes, very similar.


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## brian_ (Feb 7, 2017)

Karter2 said:


> OK,.. More feedback from Arvio..
> 
> 
> > Post by Supercaps » Today, 01:45
> ...


So, rather than DC-DC conversion "in series" with the capacitor output, they are presumably pumping the remaining charge out of some cells in a normally parallel group to the rest, probably in stages.

Man, it would have been a lot easier to have just said that. 

Someone with the patience to read their patent while mentally deleting all of the non-applicable parts, and keeping in mind that patents are intended to describe rather than explain, can see if that seems reasonable.


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## Duncan (Dec 8, 2008)

All of the electronic bits - the patents and the "secret sauce" are almost besides the point

To me the point is the 200:1 reduction in weight and the 1000:1 reduction in costs


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## ishiwgao (May 5, 2011)

Duncan said:


> All of the electronic bits - the patents and the "secret sauce" are almost besides the point
> 
> To me the point is the 200:1 reduction in weight and the 1000:1 reduction in costs


I agree with Duncan, I think the way it works and stuff doesn't matter (at least for now). if they can prove the weight and cost, then it becomes a viable product. if not it's just another product that will not see the light of day outside of exhibitions


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## Tony Bogs (Apr 12, 2014)

Not graphene this time but a superelectrolyte and stainless steel with a special sauce:

http://www.greencarcongress.com/2018/03/20180319-rr.html

Could be the next one with 180Wh/kg. 

Big name is involved: RR as in jet engines and luxury cars.


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## brian_ (Feb 7, 2017)

Tony Bogs said:


> Not graphene this time but a superelectrolyte and stainless steel with a special sauce:
> 
> http://www.greencarcongress.com/2018/03/20180319-rr.html
> 
> ...


The Rolls-Royce engine and automotive companies have been unrelated for decades... but yes, Rolls-Royce is a major and very capable manufacturer of turbine engines for various applications. That's a good thing due to the technical resources which will be available to the project, but the purpose is still to "explore the potential" of the technology.


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## Karter2 (Nov 17, 2011)

Tony Bogs said:


> Not graphene this time but a superelectrolyte and stainless steel with a special sauce:
> 
> http://www.greencarcongress.com/2018/03/20180319-rr.html
> 
> ...


Remember... Whilst they are "exploring the potential"...the Kilowattlabs guys claim they already have supercaps with 2-3 times the energy density of the units in the Sirius device !....
....which would put them in the 300Wh/kg range ,...if true.


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## Karter2 (Nov 17, 2011)

A few sneaky pics and the charge /discharge curve for the Sirius pack, from Arvio....
https://youtu.be/8MgCrdyWYoM


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## Duncan (Dec 8, 2008)

Interesting
So 8.5% at 44v and 95% at 53v

Just don't see how you do that with Supercaps unless you set the "zero" at 40v 
So if 2.7v is full then "zero" would be 1.9 volts

Maybe that is how they do it - it's actually a 12 kWh pack and they are only using the top 3.5 kWhs


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## Karter2 (Nov 17, 2011)

Duncan said:


> Maybe that is how they do it - it's actually a 12 kWh pack and they are only using the top 3.5 kWhs


 That would need those supercaps to be more like 10,000F each,...and Arvio have already stated they are 3000F devices ! ( ref page 2)


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## Duncan (Dec 8, 2008)

I think that it is much more likely that they are only using the top 1.2kWh and that the 3.5kWh is a true but irrelevant capacity

Either way those capacitors (if it's all true) represent several orders of magnitude improvement in price and in density

Lets say that they do work - and the cost is what it would appear
With some additional electronics to actually squeeze the energy out (DC-DC) they are almost at the power density to put in a car - with effectively infinite life

So carry twice as much battery weight - but your batteries last forever

Or for use in power storage where the weight is not important but the ability to be cranked up and down three times a day - 1000 cycles per year - 40,000 cycles across a 40 year life could well be vital

If these things actually exist at those prices this is a game changer


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## Karter2 (Nov 17, 2011)

OR...if they really have figured out how to get most of the energy out (8.5% remaining). Whilst holding the pack voltage minimum at 44v , then it only needs to go up to 55.5v (2.77 per cap) to hold the full 3.55 kWh. ???

So we are back to the issue that They would have to use some form of voltage boost that is not dc/dc as we understand it ?


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## brian_ (Feb 7, 2017)

We seem to be going in circles.



Duncan said:


> Interesting
> So 8.5% at 44v and 95% at 53v
> 
> Just don't see how you do that with Supercaps unless you set the "zero" at 40v
> So if 2.7v is full then "zero" would be 1.9 volts





Karter2 said:


> OR...if they really have figured out how to get most of the energy out (8.5% remaining). Whilst holding the pack voltage minimum at 44v , then it only needs to go up to 55.5v (2.77 per cap) to hold the full 3.55 kWh. ???


Right - that's how capacitors work, and what I've been saying since post #2 and first quantified in post #13. Either most of the energy is not coming out, or the caps are going down to a much lower voltage (1.9 volts if they're all in the same state). There is no other option in the real world.



Duncan said:


> I wonder - maybe the 3.6 kWh on the box is the actual storage capacity - BUT with it configured as a battery you can only *use* 1.2 kWh





Duncan said:


> Maybe that is how they do it - it's actually a 12 kWh pack and they are only using the top 3.5 kWhs





Duncan said:


> I think that it is much more likely that they are only using the top 1.2kWh and that the 3.5kWh is a true but irrelevant capacity


Okay, but in the statement quoted in post #26 the distributor explicitly said this is not the case.



Karter2 said:


> So we are back to the issue that They would have to use some form of voltage boost that is not dc/dc as we understand it ?


It's just not DC-to-DC at the place (point in the power flow) where we expect it... which they call "in series", because we would expect the output of the capacitors to go through the DC-to-DC converter to reach the load.

As I suggested earlier:


brian_ said:


> So, rather than DC-DC conversion "in series" with the capacitor output, they are presumably pumping the remaining charge out of some cells in a normally parallel group to the rest, probably in stages.


So the cells which get nearly fully discharged are taken down to much lower (well below 1.9 volts) voltage by DC-to-DC converters which add that energy to the remaining cells, which only get down to 2.2 volts (for a 44 volt series bank). They call this "high speed balancing between the parallel cell groups", although I think to most people familiar with complex batteries "balancing" means the very opposite: equalizing state of charge, not deliberately shifting charge to a selected group of cells.

Thoughts on this likely implementation, and the cost, particularly in efficiency? Is it worthwhile compared to running the entire output through a DC-to-DC inverter (given that either scheme would only be necessary once the caps drop to something like 2.2 V each)?


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## Karter2 (Nov 17, 2011)

The guys on the AEVA forum have the most likely explanation ..
http://huahuienergy.m.manufacturer....ttery/1152403017/Lithium-Titanate-Battery.htm
LTO cells , 18650 size, 1.8 - 2.75 voltage range , 1.3 Ah capacity (3.1Wh)
Looks like the vague pictures we have seen from Arvio and fits with the 20s, 60p, pack size they have confirmed.
But it does call a lie on their claim of "No lithium electrochemical cells "

But the Arvio guy (Paul Wilson) is obviously totally convinced that he is dealing with Supercaps !
He goes into some detail in this latest video.. ..from about 8mins in 
https://youtu.be/fdI1ZpRhUkI


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## weber (Apr 22, 2009)

To be fair, that video predates my revelation that you can buy unlabelled LTO cells in capacitor-style cases. And we don't know if Paul Wilson has read that yet.

The device Paul waves around between 7:23 and 7:45 in that video
https://youtu.be/fdI1ZpRhUkI?t=443
looks remarkably like the LTO cell shown here:
http://forums.aeva.asn.au/viewtopic.php?p=67093#p67093
which is unlabelled apart from a polarity stripe.


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## Duncan (Dec 8, 2008)

Why would a company use lithium cells and claim that they were supercaps?

Horribly I do think that is more likely than the huge cost and weight reductions

But I can't think of any reason for them to do that


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## weber (Apr 22, 2009)

You must have missed where they are claiming: 
1 million cycles at 100% DOD with negligible capacity fade 
a 45 year calendar life
operation without degradation at 85 °C
can be charged in less than 30 seconds without affecting cycle life
no risk of thermal runaway

See:
http://www.kilowattlabs.com/energy-storage-advantage.html
http://arvio.com.au/supercapacitor-brochure

And at 9:40 in this video, Paul Wilson implies they are completely non-toxic by claiming they are compostable, containing only carbon and paper, wrapped in aluminium.
https://youtu.be/WFef1VJHUaU?t=414

Every one of those claims would be ludicrous if they admitted it was a lithium ion battery (possibly with a few supercaps added for show). 

But as a "Capacitor Module" those claims begin to seem plausible.


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## Duncan (Dec 8, 2008)

I saw all that
But I still don't see how a company could hope to make any money doing this

If they have a huge demand - then people will open them up and see that they have been lied to

I just don't see how a company could hope to make money by selling something that is plainly not what they said it was 

With current demand and their pricing they could sell a lot - I think that they are undercutting the Tesla product - as batteries

So why claim it's something its not and open yourself up to all sorts of legal issues?


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## Karter2 (Nov 17, 2011)

Arvio (paul Wilson) are not giving up on their Supercap belief without a fight !..and a fire ! 

http://forums.aeva.asn.au/viewtopic.php?f=17&t=5486&sid=b68058e0f85dfdd0dd39686ec8931022&start=100

Is anyone around Sydney for their RoadShow in April. to ask the key questions ?
Unfortunately i will be overseas or i would love to be there.


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## weber (Apr 22, 2009)

Duncan said:


> I saw all that
> But I still don't see how a company could hope to make any money doing this
> 
> If they have a huge demand - then people will open them up and see that they have been lied to


No. When you open them up, you see what looks like unlabelled capacitors. You can't tell they are LTOs by looking at them. Nor can you easily tell they are LTOs by their voltage vs SoC curves, provided you stay within the 44 V to 54 V limits specified by the manufacturer, because LTOs happen to be fairly linear in that region, particularly at the 2C rate.

The main reasons I am fairly confident they are LTOs are:
1. I have read extensively about the current state of the art in supercapacitors, and we're nowhere-near this energy density, even in the lab, let alone mass production. And the chance that some lone genius could leapfrog everyone else by about 10 years is negligible.
2. LTO cells are commercially available that look _exactly _like the "capacitors" in the Kilowatt Labs unit and they have _exactly* _the required voltage, internal resistance, energy capacity, weight, dimensions, linear region of voltage vs charge curve, and (as we've seen most recently) flammable electrolyte. * Within 5%. [Edit: And low enough cost]

Now we're waiting for Arvio to release a 1C voltage versus charge curve that goes _outside _of the linear region for LTOs. 

At this stage, I'm assuming good faith on their part.


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## Duncan (Dec 8, 2008)

Hi Weber

But you can tell from the voltage charge curve for a supercap - the slope on that curve is equal to the capacitance 

We have been told the capacitance - 
if these are batteries then they will have an effective capacitance of about four times that

So isolating one "capacitor" and doing a voltage/current curve will show what is happenning

I would LOVE it to be the supercap breakthrough! 
But I think it's much more likely to be as you say


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## weber (Apr 22, 2009)

Duncan said:


> But you can tell from the voltage charge curve for a supercap - the slope on that curve is equal to the capacitance
> 
> We have been told the capacitance -
> if these are batteries then they will have an effective capacitance of about four times that


Sure. But then they could just say they got the capacitance wrong and they're actually _better capacitors_ than they thought! 



> So isolating one "capacitor" and doing a voltage/current curve will show what is happenning


Yes. But it has to go outside of the region where LTOs are linear. That's what I challenged them to do 4 days ago, and that's what we're still waiting for.


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## Karter2 (Nov 17, 2011)

Paul W at Arvio has now posted a video of what he claims is a "recharge test of a 3000F supercapacitor"...
https://youtu.be/m_hyyQ5-d0E
It shows one of their devices charging from 0v to 2.7 v in approx 30 secs drawing something between 15 and 10 amps (cannot see the meter )
Which would suggest he has charged approx 0.3 Wh into that device !
But that implies to me that it is not a 3000F cap is in use there ?
Its going to need a lot more than 15 amps to charge a 3000F cap in 30 secs!!


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## Duncan (Dec 8, 2008)

A 3000 Farad capacitor charged to 2.7 volts will require 8100 Coulombs

Which is 8100 Amp seconds

So if it took 30 seconds then it would average 270 amps


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## Duncan (Dec 8, 2008)

Just watched the video

He has an average of 5.5 amps for 15 minutes - 900 seconds - 4950 coulombs 

Not the full 8100 coulombs - but the way he "averaged" it looked a bit suss


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## brian_ (Feb 7, 2017)

Karter2 said:


> Paul W at Arvio has now posted a video of what he claims is a "recharge test of a 3000F supercapacitor"...
> https://youtu.be/m_hyyQ5-d0E
> It shows one of their devices charging from 0v to 2.7 v in approx 30 secs...


I didn't bother watching the whole thing or listening to any of it, but text near the beginning notes that the voltage jumps to 2.7 almost immediately. That's presumably what misled Karter2, and it is also inconsistent with a capacitor. I assume that he is charging through a control circuit which throttles the charge rate - the voltmeter is seeing 2.7 volts, but that can't be across a capacitor being charged.

Why is nothing from these people straightforward and credible?


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## brian_ (Feb 7, 2017)

Duncan said:


> Just watched the video
> 
> He has an average of 5.5 amps for 15 minutes - 900 seconds - 4950 coulombs
> 
> Not the full 8100 coulombs - but the way he "averaged" it looked a bit suss


Suspect?

I see your comment on the video; it should be interesting to see the response.


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## digsys (Aug 13, 2008)

As others have said .. plus -
IF they had said a 20-50% increase over what is currently available, I'd still be sus ... without seeing a string of patents and news articles in TECH magazines / papers. nada. At 50%, I'd be seriously skeptical though. But what they claim .. well, put up or shut-up  .. your serve


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## Karter2 (Nov 17, 2011)

Arvio uploaded a discharge test on one of the 3000F "supercaps"...
https://youtu.be/aQD8hk2llN0
Looks more like a LTO battery than ever !


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## brian_ (Feb 7, 2017)

Karter2 said:


> Arvio uploaded a discharge test on one of the 3000F "supercaps"...
> https://youtu.be/aQD8hk2llN0
> Looks more like a LTO battery than ever !


I agree... that certainly doesn't look like a capacitor discharge curve!


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## Duncan (Dec 8, 2008)

Just boosting this back up - anybody got any updates?


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## weber (Apr 22, 2009)

See
http://forums.aeva.asn.au/viewtopic.php?p=67163#p67163
and
http://whrl.pl/Re7JYv

In particular see the new type of USB-chargeable AA-sized "supercapacitor" from Arvio here:
http://forums.aeva.asn.au/viewtopic.php?p=67289#p67289


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## MattsAwesomeStuff (Aug 10, 2017)

Old news is old but...



Duncan said:


> So 8.5% at 44v and 95% at 53v
> 
> Just don't see how you do that with Supercaps unless you set the "zero" at 40v
> So if 2.7v is full then "zero" would be 1.9 volts
> ...


The energy stored in a capacitor is not linear with voltage as it (sort of) is with batteries.

Energy = Capacitance * Voltage * Voltage / 2

So at double the voltage you have 4x as much energy. At 4x the voltage you have 16x as much energy.

It does actually make sense that the voltage skyrockets immediately under very little current flow, and that by the time you drain it even to half voltage, most of the energy is long gone.

Vaporwear is vaporwear.


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## Duncan (Dec 8, 2008)

Good point so if it was 1.9v to 2.7v

That would be 3.61 to 7.29

So the 3.55kWh pack would actually be a 7 kWh pack that they were only using 3.55 kWh


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## Karter2 (Nov 17, 2011)

But the basics remain..
There is no known capacitor device that can give this capacity , in this size , or at this weight...let alone cost.
ALL the data and evidence still confirms that this is using LTO cells..
...just as those new "supercapacitor rechargeable" AA cells are also !
Its all on the AEVA forum


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## weber (Apr 22, 2009)

MattsAwesomeStuff said:


> The energy stored in a capacitor is not linear with voltage as it (sort of) is with batteries.
> 
> Energy = Capacitance * Voltage * Voltage / 2
> 
> ...


This would only be relevant if the charge tests used constant power. They don't. Some are constant voltage (where the device's internal resistance limits the current), others are constant current. With constant current, voltage increases linearly with time for a capacitor.

But even if it was relevant: When you transpose the above equation to give the voltage as a function of the energy, you get: Voltage = sqrt(2 x Energy). Sure, that starts off steeper than it ends, but it is a very smooth and rounded sort of curve. The curves for this device have a very sharp knee in them at around 1.8 to 2.0 volts.


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## MattsAwesomeStuff (Aug 10, 2017)

> With constant current, voltage increases linearly with time for a capacitor.


I don't think that's true.

As you add energy into the capacitor, voltage increases as per the formula.

In any case, was just nitpicking a point Duncan made.

It's important when something is bullshit, that the reasons you debunk it aren't bullshit too. This thing is bullshit enough that it is plenty sufficient to debunk it using a dozen valid arguments, so it's important to make sure those are accurate. Duncan was on the right track but, off on one attribute.

I say this as someone who occasionally picks up bits of context in threads like this and finds out years later it was wrong, or years later come across threads like this where no one corrected it and then "learns" something untrue.

Evidence is clear they're LTOs, nothing to see here.


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## Duncan (Dec 8, 2008)

MattsAwesomeStuff said:


> Evidence is clear they're LTOs, nothing to see here.


You are probably right but I'm still struggling with why a company would try and sell something that was not what they say it was

A one off sale? - sure con men are everywhere

But a mass produced article where they would need to sell thousands just to cover the initial costs?


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## weber (Apr 22, 2009)

MattsAwesomeStuff said:


> I don't think that's true.
> 
> As you add energy into the capacitor, voltage increases as per the formula.


Yes. But constant current doesn't correspond to constant energy per time, it corresponds to constant charge per time. And, for a capacitor, voltage is charge divided by capacitance and energy is charge times voltage. So constant current means energy is going up as the square of time. And since voltage goes up as the square root of energy, voltage goes up linearly with time.



> It's important when something is bullshit, that the reasons you debunk it aren't bullshit too.


Yes. Absolutely. So please, don't take my word for it. Look this up elsewhere, to understand where you're going wrong.



> Evidence is clear they're LTOs, nothing to see here.


Agreed.


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## MattsAwesomeStuff (Aug 10, 2017)

Hopefully not a hijack, not sure this thread has much more use in it, after its thorough debunking...



weber said:


> Yes. But constant current doesn't correspond to constant energy per time, it corresponds to constant charge per time. And, for a capacitor, voltage is charge divided by capacitance and energy is charge times voltage. So constant current means energy is going up as the square of time. And since voltage goes up as the square root of energy, voltage goes up linearly with time.


Hrm, I'm half-following you here. (I'm sure it's a fine explanation, but I have only a beginner's grasp of it). I get that energy and current are different, and that voltage starting low means energy going in starts lower, I'm just not sure the two cancel out entirely, one is squared, one seems linear to me.

But let me rephrase what you're claiming...

If I take a constant-current power supply, set it to some low current with a max voltage of whatever my capacitor is, and pick a capacitor that is large enough that it charging is watchable on a human-timescale...

Suppose I pick a 50v capacitor. And I measure and it takes, oh, 5 minutes to charge at whatever rate I picked. You're saying that at 1 minute it was at 10v, 2 minutes it was at 20v, 3 minutes it was at 30v, 4 minutes it was at 40v along the way?

I'll have to try that on some suitably-sized capacitor some time.


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## weber (Apr 22, 2009)

Yes. That's exactly what I'm saying.


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## brian_ (Feb 7, 2017)

Duncan said:


> ... So the 3.55kWh pack would actually be a 7 kWh pack that they were only using 3.55 kWh


But again, the distributor (the manufacturer is nowhere to be seen in this discussions) has repeatedly claimed that they are using all of the energy in the capacitors, not just partially discharging them.


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## Karter2 (Nov 17, 2011)

Arvio keep shooting themselves in the (reputation) foot over on the AEVA forum.
http://forums.aeva.asn.au/viewtopic.php?f=17&t=5486&start=200
Thankfully, weber is doing a great job of hosing down the BS. !


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## MattsAwesomeStuff (Aug 10, 2017)

> Thankfully, weber is doing a great job of hosing down the BS. !


Weber just slayin' their claims left and right.

'We're still waiting for you to explain why, when you remove the Kilowatt Labs sticker from your claimed USB-chargeable AA-sized "graphene supercapacitor", it says "LTO" and "battery"? And why the words "graphene" and "capacitor" are nowhere to be found?'

Merciless


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## Duncan (Dec 8, 2008)

Just bumping this thread as they have started selling these here in NZ - the 3.55 kWh unit is about $4K so I don't think I'm going to buy one just to pull it apart

But any more news from Australia where they are a year ahead of us


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## somecallmetim (Sep 18, 2019)

I've been curious about using a supercapacitor for energy storage for some time. I don't think the value proposition is to replace a battery for the same purpose, but perhaps in a similar location in the drive train, with a different function.


A supercapacitor charges and discharges very easily. Charge is stored as charge, rather than requiring chemical conversion to store energy and chemical conversion to release energy.

The contrast with a battery is that a battery must be large - not just to provide range, but also to allow maximum discharge current. How many "C"s are you willing to push your battery to in order to accelerate? If you keep the discharge per battery low, you need a larger capacity battery to source a given amount of current. That adds significant weight, and significant cost.


A supercap in a series hybrid would just function to provide power spikes at acceleration / deceleration, and keep the motor at peak efficiency.



I'm more interested in using supercapacitors as temporary energy storage, between a generator (or alternator with appropriate converter) and my electric traction motor. If I can supply the large current needed for acceleration and accept the large current generated with braking...that is the benefit.


This would need to be paired with an ICE or microturbine or free piston generator or... that would run near optimum efficiency to keep the supercapacitors at a programmed charge level.


I think that Ariel is working with Delta Motorsports on this sort of idea, and a couple of Chinese companies are as well (techrules comes to mind, but I think there is another that I can't recall at the moment).


Hypothetical (until I pull the switch )...


A tube frame car that weights 1700 lbs with low drag. Current versions use an ICE with a 160 HP engine and a 4-5 speed. The engine and transmission weigh about 205 kg (450 pounds). From my rough estimates, I could get a sufficient synchronous motor and gear reducer for 75 kg. Supercapacitor would weigh (much less than batteries) about 180 kg for 500V. I need a 20-30 kW generator. I could go wankel, microturbine, or freepiston...all of which are in the 15-20 kg range. 



All told, on paper it looks to be about 75 kg heavier than the ICE version, with plenty of acceleration, optimum efficiency of the ICE, and no battery issues. Since an electric motor can be mounted transversely with gear reducer dumping power out on a parallel axis to the motor rotation, very low losses occur between motor and wheels.


Any thoughts on this sort of application?


Cheers...


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