# [EVDL] Lithium Ion vs a 31 farad Ultra-capacitor (Long)



## EVDL List (Jul 27, 2007)

Hey fellow Lister's its been a long time since I posted here but felt this information worthy.
So I would like to present to the list a fascinating new working ultra capacitor.

Before you go ya right and what planet are you on I suggest you catch the pod-cast and read the patent yourself.
Those on the EVDL I think will find this a good listen and I think is more than just a promise and a fantasy energy storage device.

Okay dig this.
A lass than 300 pound 52KW-H Ultra Capacitor.
Takes up 2.6 cubic feet.
No toxins.
Can take 360 amps if you can possibly throw that much at it.
Unlimited charge cycles.
Less than .1 percent self discharge rate over one month.
Sounds to good be true?
The patent describes the working prototype and how one can make this beast of a capacitor.

Go to the last half hour of the 2 hour Pod-cast show to hear Steve Gibson who normally discusses internet security, he radically deviates to battery technology and the Tesla and other stuff and their future implications 

Podcast>>>
http://twit.tv/sn177

Here is the patent brief filed 12/16/200 on this ultra-cap.

11 Page Patent describing in detail the manufature and other specific details.
http://www.pat2pdf.org/patents/pat7466536.pdf

Enjoy Danny.

An electrical-energy-storage-unit (ESSU) has a basis material is a high-permittivity composition-modified barium titanate ceramic powder. This powder is single coated with 
aluminum oxide and then immersed is a matrix of poly (ethylene terephthalate) (PET) plastic for use in screen-printing systems. The ink that is used to process the powders a 
screen-printing is based on nitrocellulose resin that provide a binder burnout, sintering, and hot isostatic pressing temperature's that are in the range of 40 C. to 150 C also allows aluminum powder to be used for the electrode material. The components of the EESU are manufactured with the use of conventional techniques which include screen printing alternating multilayers of aluminum electrodes and high permittivity composition-modified barium titanate powder, sinterin to a close-pore porous body, followed by isostatic pressing to void-free body. The 31,351 components are configured into a multilayer array with the use of a solder-bump technique as the enabling technology so as to provide a parallel configuration of components that has the capability to store at least 52.22 Kilo Watt Hours of electrical energy. The total weight of an EESU with this amount of electrical energy storage is 281.56 pounds including the box, connectors, and associated
hardware.
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## EVDL List (Jul 27, 2007)

EEStor's ultracapacitor seems like a very promising technology. I read
through their patent a few weeks ago, and their technical descriptions sound
very good, not at all like the pseudoscience I've come to expect from
"miracle battery" manufacturers. Lockheed Martin's investment in their
company is also a promising sign to the validity of their claims.

It concerns me that there's no publicly available proof of their claims.
However, they have no reason to try to prove anything to the public yet.

Also, the extremely high voltage and power capability of this capacitor
present a challenge to find or design safe, affordable fuses and contactors.
In addition, the high voltage involved requires a somewhat expensive
converter to provide a useful, safe output voltage.

ZENN motors has signed an exclusive agreement for use of these
ultracapacitors in vehicles under 1400kg. This limits the potential market
for their product.

Despite these problems, I am very excited about the technology. If it's
actually produced as claimed, I would buy one as soon as possible.

-Morgan LaMoore



> Danny Ames <[email protected]> wrote:
> 
> > Hey fellow Lister's its been a long time since I posted here but felt this
> > information worthy.
> ...


----------



## EVDL List (Jul 27, 2007)

> Morgan LaMoore wrote:
> > Also, the extremely high voltage and power capability of this capacitor
> > present a challenge to find or design safe, affordable fuses and contactors.
> > In addition, the high voltage involved requires a somewhat expensive
> ...


----------



## EVDL List (Jul 27, 2007)

An electrostatic storage device has a voltage the changes with state of 
charge, just like any capacitor.
In order to use this, you need an awesome range,power, and efficient dc-dc.
Otherwise the useable rang is so small you are wasteing most of it.

With an electorchemical starage device the chemical reaction has a 
voltage and it stays nearly constant across the soc.

Lead acid is the worst at maintaining the voltage and the graph is soft 
because of the pukerts effect
But full is 12.77 and empty is 11.00 at moderate loads.

Lets look at a 288V nominal pack to 50% DOD
307V charged and 290V Discharged. 307-290 / (307+290)/2 = 5.6% voltage drop

A capacitor to 50%
307V
1/2 C V^2 = 47124.5C /2 = 23562.25C => 153V

@ 153V you amperage doubles on your awsome dc-dc or your power is half 
what it was and things don't work correctly.

Try to extent this analysis to useing 80% of the energy and you will see 
where the awsome dc-dc becomes a chain of multiple stage awsome dc-dc's 
I think we have to realize we can only use 50% of the Electrostatic 
storage for voltage/soc reasons. For lead we use 50% for pukerts and 
lifecycle.

So the practical use will probably as a secondary storage. Use a battery 
that never is fully charged for immediate loads and use a bidirectional 
dc-dc with about cruising amps only capacity to pull off the regen and 
recharge the pack during cruise.


> EEStor's ultracapacitor seems like a very promising technology. I read
> through their patent a few weeks ago, and their technical descriptions sound
> very good, not at all like the pseudoscience I've come to expect from
> "miracle battery" manufacturers. Lockheed Martin's investment in their
> company is also a promising sign to the validity of their claims.
>
> It concerns me that there's no publicly available proof of their claims.
> However, they have no reason to try to prove anything to the public yet.
>
> Also, the extremely high voltage and power capability of this capacitor
> present a challenge to find or design safe, affordable fuses and contactors.
> In addition, the high voltage involved requires a somewhat expensive
> converter to provide a useful, safe output voltage.
>
> ZENN motors has signed an exclusive agreement for use of these
> ultracapacitors in vehicles under 1400kg. This limits the potential market
> for their product.
>
> Despite these problems, I am very excited about the technology. If it's
> actually produced as claimed, I would buy one as soon as possible.
>
> -Morgan LaMoore
> 

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## EVDL List (Jul 27, 2007)

> Date: Sun, 4 Jan 2009 07:56:49 -0800> From: [email protected]> To: ev=
@lists.sjsu.edu> Subject: Re: [EVDL] Lithium Ion vs a 31 farad Ultra-capaci=
tor (Long)> > An electrostatic storage device has a voltage the changes wit=
h state of > charge, just like any capacitor.> In order to use this, you ne=
ed an awesome range,power, and efficient dc-dc.> Otherwise the useable rang=
is so small you are wasteing most of it.> > With an electorchemical starag=
e device the chemical reaction has a > voltage and it stays nearly consta=
nt across the soc.> > Lead acid is the worst at maintaining the voltage and=
the graph is soft > because of the pukerts effect> But full is 12.77 and e=
mpty is 11.00 at moderate loads.> > Lets look at a 288V nominal pack to 50%=
DOD> 307V charged and 290V Discharged. 307-290 / (307+290)/2 =3D 5.6% volt=
age drop> > A capacitor to 50%> 307V> 1/2 C V^2 =3D 47124.5C /2 =3D 23562.=
25C =3D> 153VJeff- you got the equation right, but then ended up with the w=
rong voltage - you didn't pay attention to the v-squared term . A 307 V ca=
pacitor is at 50% DOD ( energy-wise) at 217 volts, so it's not as bad as y=
ou think. Phil Marino> > @ 153V you amperage doubles on your awsome dc-dc =
or your power is half > what it was and things don't work correctly.> > Try=
to extent this analysis to useing 80% of the energy and you will see > whe=
re the awsome dc-dc becomes a chain of multiple stage awsome dc-dc's > I th=
ink we have to realize we can only use 50% of the Electrostatic > storage f=
or voltage/soc reasons. For lead we use 50% for pukerts and > lifecycle.> >=
So the practical use will probably as a secondary storage. Use a battery >=
that never is fully charged for immediate loads and use a bidirectional > =
dc-dc with about cruising amps only capacity to pull off the regen and > re=
charge the pack during cruise.> > >> EEStor's ultracapacitor seems like a v=
ery promising technology. I read>> through their patent a few weeks ago, an=
d their technical descriptions sound>> very good, not at all like the pseud=
oscience I've come to expect from>> "miracle battery" manufacturers. Lockhe=
ed Martin's investment in their>> company is also a promising sign to the v=
alidity of their claims.>>>> It concerns me that there's no publicly availa=
ble proof of their claims.>> However, they have no reason to try to prove a=
nything to the public yet.>>>> Also, the extremely high voltage and power c=
apability of this capacitor>> present a challenge to find or design safe, a=
ffordable fuses and contactors.>> In addition, the high voltage involved re=
quires a somewhat expensive>> converter to provide a useful, safe output vo=
ltage.>>>> ZENN motors has signed an exclusive agreement for use of these>>=
ultracapacitors in vehicles under 1400kg. This limits the potential market=
>> for their product.>>>> Despite these problems, I am very excited about t=
he technology. If it's>> actually produced as claimed, I would buy one as s=
oon as possible.>>>> -Morgan LaMoore>> > > ______________________________=
_________________> General EVDL support: http://evdl.org/help/> Usage guide=
lines: http://evdl.org/help/index.html#conv> Archives: http://evdl.org/arch=
ive/> Subscription options: http://lists.sjsu.edu/mailman/listinfo/ev> =

_________________________________________________________________
Life on your PC is safer, easier, and more enjoyable with Windows Vista=AE. =

http://clk.atdmt.com/MRT/go/127032870/direct/01/
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## EVDL List (Jul 27, 2007)

> They'll come with a built-in bidirectional DC-DC. I've read this a
> couple times but can't remember where, but you can see a reference to it
> here:

It's a challenge for the EEStor engineers, not for us. It's still a
downside of the technology, though, and adds to the total cost of the
system.

Additionally, according to EEStor's patent, they performed life
testing using 2 second charge-discharge cycles (on one "component",
not a full battery). If true, then EEStor is capable of performance
far beyond even A123, limited only by the power electronics and
possibly interconnects. This claim seems plausible because EEStor
works like a ceramic capacitor, using electric fields instead of the
chemical reactions of a battery.

Thus, if you could design a higher power safety switch and converter,
you would end up with the capacity of a Tesla Roadster and the power
of the Killacycle (or higher). Such a converter would be quite
expensive, though (probably more expensive than a Zilla). One possible
path is multiple, lower-current converters in parallel.

-Morgan LaMoore



> Cory Cross <[email protected]> wrote:
> >
> > Morgan LaMoore wrote:
> > > Also, the extremely high voltage and power capability of this capacitor
> ...


----------



## EVDL List (Jul 27, 2007)

What did I miss?
1/2 CV^2 =3D .5 * C * 307^2 =3D 47124.5
47124.5 / 2 =3D 23562.25 (50%)
*2 and sqrt =3D 217
=

Oh, duh, I missed the .5 not the squareroot. Looks like we both needed =

another cup of coffee 

307-217 / (307+217)/2 or 34%

Still awful. Add the comparison to LiFePo4 and it will be more dramatic.

All this points to the need for a dc-dc and the other baggage we must =

carry.
I have long believed a merging of the two, electrochemical and =

electrostatic, will be the next big step.

I look at the percent you get out vs the amount of support you need and =

for primary storage, The electrochemical cell seems to still win. Now =

for regen energy the cap has more potential(Pun intended).
My problem with fuel cells is the ratio of support equipment needed to =

what you get out of them.


=


>> > Date: Sun, 4 Jan 2009 07:56:49 -0800> From: [email protected]> To:=
[email protected]> Subject: Re: [EVDL] Lithium Ion vs a 31 farad Ultra-cap=
acitor (Long)> > An electrostatic storage device has a voltage the changes =
with state of > charge, just like any capacitor.> In order to use this, you=
need an awesome range,power, and efficient dc-dc.> Otherwise the useable r=
ang is so small you are wasteing most of it.> > With an electorchemical sta=
rage device the chemical reaction has a > voltage and it stays nearly con=
stant across the soc.> > Lead acid is the worst at maintaining the voltage =
and the graph is soft > because of the pukerts effect> But full is 12.77 an=
d empty is 11.00 at moderate loads.> > Lets look at a 288V nominal pack to =
50% DOD> 307V charged and 290V Discharged. 307-290 / (307+290)/2 =3D 5.6% v=
oltage drop> > A capacitor to 50%> 307V> 1/2 C V2 =3D 47124.5C /2 =3D 2356=
2.25C =3D> 153VJeff- you got the equation right, but then ended up with the=
wrong voltage - you didn't pay attention to the v-squared term . A 307 V =
capacitor is at 50% DOD ( energy-wise) at 217 volts, so it's not as bad as=
you think. Phil Marino> > @ 153V you amperage doubles on your awsome dc-d=
c or your power is half > what it was and things don't work correctly.> > T=
ry to extent this analysis to useing 80% of the energy and you will see > w=
here the awsome dc-dc becomes a chain of multiple stage awsome dc-dc's > I =
think we have to realize we can only use 50% of the Electrostatic > storage=
for voltage/soc reasons. For lead we use 50% for pukerts and > lifecycle.>=
> So the practical use will probably as a secondary storage. Use a battery=
> that never is fully charged for immediate loads and use a bidirectional =
> dc-dc with about cruising amps only capacity to pull off the regen and > =
recharge the pack during cruise.> > >> EEStor's ultracapacitor seems like a=
very promising technology. I read>> through their patent a few weeks ago, =
and their technical descriptions sound>> very good, not at all like the pse=
udoscience I've come to expect from>> "miracle battery" manufacturers. Lock=
heed Martin's investment in their>> company is also a promising sign to the=
validity of their claims.>>>> It concerns me that there's no publicly avai=
lable proof of their claims.>> However, they have no reason to try to prove=
anything to the public yet.>>>> Also, the extremely high voltage and power=
capability of this capacitor>> present a challenge to find or design safe,=
affordable fuses and contactors.>> In addition, the high voltage involved =
requires a somewhat expensive>> converter to provide a useful, safe output =
voltage.>>>> ZENN motors has signed an exclusive agreement for use of these=
>> ultracapacitors in vehicles under 1400kg. This limits the potential mark=
et>> for their product.>>>> Despite these problems, I am very excited about=
the technology. If it's>> actually produced as claimed, I would buy one as=
soon as possible.>>>> -Morgan LaMoore>> > > ____________________________=
___________________> General EVDL support: http://evdl.org/help/> Usage gui=
delines: http://evdl.org/help/index.html#conv> Archives: http://evdl.org/ar=
chive/> Subscription options: http://lists.sjsu.edu/mailman/listinfo/ev> =

>> =

> _________________________________________________________________
> Life on your PC is safer, easier, and more enjoyable with Windows Vista=
=AE. =

> http://clk.atdmt.com/MRT/go/127032870/direct/01/
> =



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## EVDL List (Jul 27, 2007)

> An electrostatic storage device has a voltage the changes with state of
> charge, just like any capacitor.
> In order to use this, you need an awesome range,power, and efficient dc-dc.
> Otherwise the useable rang is so small you are wasteing most of it.

If I were going to build a DC-DC for EEStor, I would use a multi-phase
synchronous soft-switched buck converter using high-voltage IGBTs.

Synchrous operation allows it to charge the capacitor from the DC bus
(with the right control circuitry). This would allow high power regen
and charging.

Multi-phase operation would allow you to use a lower switching
frequency to lower switching losses while keeping the filter size
down. It also avoids current sharing issues between IGBTs because you
can run each phase with its own current control loop.

Of course soft switching helps avoid the huge switching losses with
such voltages.

If you used a high-voltage AC controller with an 800V bus (like the
200kW EVISOL) and your control loop can go up to 100% duty cycle, then
you use almost 95% of the energy stored as the cap falls from 3500V to
800V. In addition, the controller can continue operating at reduced
power down to its low voltage cutoff.

With an 800V bus, you need 250A output capability for 200kW. If you
can switch 20A per power stage with the low frequency and soft
switching, then you'd need 26 transistors in the converter. It's a
lot, but not too excessive.

With a high-voltage Zilla, you need about twice as many transistors,
but your energy usage is even better.

There's no question that the converter is expensive, but if the
capacitor performs as described, I think it's well worth it.

-Morgan LaMoore



> Jeff Shanab <[email protected]> wrote:
> > An electrostatic storage device has a voltage the changes with state of
> > charge, just like any capacitor.
> > In order to use this, you need an awesome range,power, and efficient dc-dc.
> ...


----------



## EVDL List (Jul 27, 2007)

Wow, Sounds expensive. You may be right that it is worth it, but the 
proof is in the pudding.
Let me know when you have specs and price. 
>> > An electrostatic storage device has a voltage the changes with state of
>> > charge, just like any capacitor.
>> > In order to use this, you need an awesome range,power, and efficient dc-dc.
>> > Otherwise the useable rang is so small you are wasteing most of it.
>> 
>
> If I were going to build a DC-DC for EEStor, I would use a multi-phase
> synchronous soft-switched buck converter using high-voltage IGBTs.
>
> Synchrous operation allows it to charge the capacitor from the DC bus
> (with the right control circuitry). This would allow high power regen
> and charging.
>
> Multi-phase operation would allow you to use a lower switching
> frequency to lower switching losses while keeping the filter size
> down. It also avoids current sharing issues between IGBTs because you
> can run each phase with its own current control loop.
>
> Of course soft switching helps avoid the huge switching losses with
> such voltages.
>
> If you used a high-voltage AC controller with an 800V bus (like the
> 200kW EVISOL) and your control loop can go up to 100% duty cycle, then
> you use almost 95% of the energy stored as the cap falls from 3500V to
> 800V. In addition, the controller can continue operating at reduced
> power down to its low voltage cutoff.
>
> With an 800V bus, you need 250A output capability for 200kW. If you
> can switch 20A per power stage with the low frequency and soft
> switching, then you'd need 26 transistors in the converter. It's a
> lot, but not too excessive.
>
> With a high-voltage Zilla, you need about twice as many transistors,
> but your energy usage is even better.
>
> There's no question that the converter is expensive, but if the
> capacitor performs as described, I think it's well worth it.
>
> -Morgan LaMoore
>
>


> Jeff Shanab <[email protected]> wrote:
> >
> >> > An electrostatic storage device has a voltage the changes with state of
> >> > charge, just like any capacitor.
> ...


----------



## EVDL List (Jul 27, 2007)

Every few months the same discussion around EEstor and
capacitive energy storage is done all over once again.
Luckily the laws of physics are not so short of memory,
so they remember -as Steve indicated- that energy storage
goes with the square of the voltage, the main reason that
EEstor works at this high voltage.
Removing 75% of the energy from a capacitor brings its
voltage down to half.
This is not too much different than a 12V lead-acid battery
which needs charging up 16V and can be discharged under load
to close to 9V so this is very close to the same 50%.

Regarding a bi-direction DC/DC: these have already been
produced in over a million units for the NHW-20 Prius
which is mistakenly called 2nd generation in the USA but
is really the 3rd, counting the NHW-10 which was only sold
in Japan but is driven through grey-import in other countries
where traffic is using the left side of the road; followed by
the first USA release which is really the 2nd gen NHW-11, for
sale in the model years 2001-2003.
Every Prius after this has a 200V to 500V bi-directional
DC/DC built in and the cost is apparently not prohibitive,
seeing that the price increase for the 3rd gen was moderate
and many other features were also released at the same time,
such as an all-electric AirCo, Bluetooth and electronic
gadgets such as automatic opening doors, coolant heat storage
and not the least a larger and completely re-styled body.

Apparently the key is in the volume production, so that the
price is much closer to the (component) costs than at low
volume - as always.

Regards and have a Prosperous and Blessed New Year!

Cor van de Water
Director HW & Systems Architecture Group
Proxim Wireless Corporation http://www.proxim.com
Email: [email protected] Private: http://www.cvandewater.com
Skype: cor_van_de_water IM: [email protected]
Tel: +1 408 383 7626 VoIP: +31 20 3987567 FWD# 25925
Tel: +91 (040)23117400 x203 XoIP: +31877841130

Please consider the environment before printing this e-mail.
-----Original Message-----
From: [email protected] [mailto:[email protected]] On
Behalf Of Jeff Shanab
Sent: Monday, January 05, 2009 8:43 AM
To: [email protected]
Subject: Re: [EVDL] Lithium Ion vs a 31 farad Ultra-capacitor (Long)

Wow, Sounds expensive. You may be right that it is worth it, but the
proof is in the pudding.
Let me know when you have specs and price. 
>> > An electrostatic storage device has a voltage the changes with 
>> > state of charge, just like any capacitor.
>> > In order to use this, you need an awesome range,power, and
efficient dc-dc.
>> > Otherwise the useable rang is so small you are wasteing most of it.
>> 
>
> If I were going to build a DC-DC for EEStor, I would use a multi-phase

> synchronous soft-switched buck converter using high-voltage IGBTs....

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General EVDL support: http://evdl.org/help/
Usage guidelines: http://evdl.org/help/index.html#conv
Archives: http://evdl.org/archive/
Subscription options: http://lists.sjsu.edu/mailman/listinfo/ev


----------



## EVDL List (Jul 27, 2007)

Every few months the same discussion around EEstor and
capacitive energy storage is done all over once again.
Luckily the laws of physics are not so short of memory,
so they remember -as Steve indicated- that energy storage
goes with the square of the voltage, the main reason that
EEstor works at this high voltage.
Removing 75% of the energy from a capacitor brings its
voltage down to half.
This is not too much different than a 12V lead-acid battery
which needs charging up 16V and can be discharged under load
to close to 9V so this is very close to the same 50%.

Regarding a bi-direction DC/DC: these have already been
produced in over a million units for the NHW-20 Prius
which is mistakenly called 2nd generation in the USA but
is really the 3rd, counting the NHW-10 which was only sold
in Japan but is driven through grey-import in other countries
where traffic is using the left side of the road; followed by
the first USA release which is really the 2nd gen NHW-11, for
sale in the model years 2001-2003.
Every Prius after this has a 200V to 500V bi-directional
DC/DC built in and the cost is apparently not prohibitive,
seeing that the price increase for the 3rd gen was moderate
and many other features were also released at the same time,
such as an all-electric AirCo, Bluetooth and electronic
gadgets such as automatic opening doors, coolant heat storage
and not the least a larger and completely re-styled body.

Apparently the key is in the volume production, so that the
price is much closer to the (component) costs than at low
volume - as always.

Regards and have a Prosperous and Blessed New Year!

Cor van de Water
Director HW & Systems Architecture Group
Proxim Wireless Corporation http://www.proxim.com
Email: [email protected] Private: http://www.cvandewater.com
Skype: cor_van_de_water IM: [email protected]
Tel: +1 408 383 7626 VoIP: +31 20 3987567 FWD# 25925
Tel: +91 (040)23117400 x203 XoIP: +31877841130

Please consider the environment before printing this e-mail.
-----Original Message-----
From: [email protected] [mailto:[email protected]] On
Behalf Of Jeff Shanab
Sent: Monday, January 05, 2009 8:43 AM
To: [email protected]
Subject: Re: [EVDL] Lithium Ion vs a 31 farad Ultra-capacitor (Long)

Wow, Sounds expensive. You may be right that it is worth it, but the
proof is in the pudding.
Let me know when you have specs and price. 
>> > An electrostatic storage device has a voltage the changes with 
>> > state of charge, just like any capacitor.
>> > In order to use this, you need an awesome range,power, and
efficient dc-dc.
>> > Otherwise the useable rang is so small you are wasteing most of it.
>> 
>
> If I were going to build a DC-DC for EEStor, I would use a multi-phase

> synchronous soft-switched buck converter using high-voltage IGBTs....

_______________________________________________
General EVDL support: http://evdl.org/help/
Usage guidelines: http://evdl.org/help/index.html#conv
Archives: http://evdl.org/archive/
Subscription options: http://lists.sjsu.edu/mailman/listinfo/ev


----------



## EVDL List (Jul 27, 2007)

> Jeff Shanab wrote:
> > An electrostatic storage device has a voltage the changes with state of
> > charge, just like any capacitor.
> > In order to use this, you need an awesome range,power, and efficient dc-dc.
> ...


----------

