Race Pack vs Street Pack

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Race Pack vs Street Pack

drdhdmd
Well now that I have the Z2K in the eLectric DeLorean I have to figure out a way to get it going faster that 60mph in the quarter mile.  I was thinking of going to a higher voltage pack compaired to the thirteen Deka 9A31s I have now but it looks like if I use more but smaller 12V batteries that my voltage will be higher but my peak current will be lower.

Is there a way to configure a battery pack for maximum range and reconfigure it for maximum 1/4 mile speed?

Even if I switch to Li batteries it looks like four 100AH batteries will fit in the space of one 9A31.  This doesn't leave much more room than 13 x 4 = 52 cells.

Thank you,

Dave Delman
eLectricdelorean.com
evalbum.com/1482

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Re: Race Pack vs Street Pack

damon henry

Hi Dave,

For good racing information you should join the Nedra list on Yahoo if you have not already.  Some of the longtime EVDL contributors who are very into racing have moved exclusively to that list due to a fallout with the EVDL moderator.

In short, experience has shown that the best Lead Acid EV racing battery is a 16 ahr Hawker or one of it's rebranded derivitives like the aerobatterys.  These are small and lightweight yet have proven to pound out between 700 and 800 amps for a quarter mile before beginning to pop.  So either a single high voltage string of these with the battery current limit turned down appropriately, or a duel string with the battery limit turned up in the 1500 amp range are likely to be your best 1/4 mile lead acid options.  As far as daily driving and range goes as long as you stick with lead acid you can pretty much just go by the weight of the overall pack.  Brand and voltage/current configuration will make little difference compared to how many pounds of lead you are willing to pack around.

Lithium is still mostly uncharted territory.  Obviously Bill Dube and the Killacycle have proven that a well engineered pack of A123s can give you incredible track performance, what may be a little less understood is that the same pack will also give you great range.  When John Wayland dropped the spare Killacycle pack into the White Zombie his range and the stiffness of the pack were much better than his lead acid racing pack.  There are still many other lithium options to be explored, but for most they still cost too much money.

Anyway, the best way to keep up with EV racing is to follow Nedra.

damon

> To: [hidden email]
> From: [hidden email]
> Date: Tue, 12 May 2009 13:49:00 -0400
> Subject: [EVDL] Race Pack vs Street Pack
>
> Well now that I have the Z2K in the eLectric DeLorean I have to figure out a way to get it going faster that 60mph in the quarter mile.  I was thinking of going to a higher voltage pack compaired to the thirteen Deka 9A31s I have now but it looks like if I use more but smaller 12V batteries that my voltage will be higher but my peak current will be lower.
>
> Is there a way to configure a battery pack for maximum range and reconfigure it for maximum 1/4 mile speed?
>
> Even if I switch to Li batteries it looks like four 100AH batteries will fit in the space of one 9A31.  This doesn't leave much more room than 13 x 4 = 52 cells.
>
> Thank you,
>
> Dave Delman
> eLectricdelorean.com
> evalbum.com/1482
>
> _______________________________________________
> General EVDL support: http://evdl.org/help/
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Re: Race Pack vs Street Pack

Roland Wiench
In reply to this post by drdhdmd
Hello Dave,

What you need is a flux or I mean a supercapacitor that is install parallel
with a lighter weight battery pack.  This is what I am going to do with my
next battery pack change.  Instead of 260 AH battery pack at 180 volts, I am
going to 252 volt pack, using one of the U.S. Battery deep cycle packs at
150 AH using one of Tavrima supercapacitors and still be about 600 lbs
lighter.

My range in a 7010 lb EV at 50% SOC is 69 miles with the 260 AH pack will be
about 62 miles with the 150 AH pack with out the supercapacitor, but the
range and life of the batteries should improve using this device.

See at:  http://www.tavrima.com/home.html

Roland




----- Original Message -----
From: "Dave Delman" <[hidden email]>
To: <[hidden email]>
Sent: Tuesday, May 12, 2009 10:49 AM
Subject: [EVDL] Race Pack vs Street Pack


> Well now that I have the Z2K in the eLectric DeLorean I have to figure out
> a way to get it going faster that 60mph in the quarter mile.  I was
> thinking of going to a higher voltage pack compaired to the thirteen Deka
> 9A31s I have now but it looks like if I use more but smaller 12V batteries
> that my voltage will be higher but my peak current will be lower.
>
> Is there a way to configure a battery pack for maximum range and
> reconfigure it for maximum 1/4 mile speed?
>
> Even if I switch to Li batteries it looks like four 100AH batteries will
> fit in the space of one 9A31.  This doesn't leave much more room than 13 x
> 4 = 52 cells.
>
> Thank you,
>
> Dave Delman
> eLectricdelorean.com
> evalbum.com/1482
>
> _______________________________________________
> 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
>
>

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Re: Race Pack vs Street Pack

Jeff Major
In reply to this post by drdhdmd


--- On Tue, 5/12/09, Dave Delman <[hidden email]> wrote:

> Is there a way to configure a battery pack for maximum
> range and reconfigure it for maximum 1/4 mile speed?
>

Dave,

The race pack needs high power and low mass.  The street pack needs high energy. You will suffer on the drag strip if you carry the street pack with you, as well as the charger, DC/DC and other such items.  Seems to me, you will want to remove the street pack, not reconfigure it. I guess it depends on the battery type and system design if you would want to leave the race pack in there along with the street pack for everyday use.

The ideal race pack would deliver the required power and have just enough energy for one pass.  That way you don't carry any unused mass with you which slows acceleration.  This seems to be impossible to do with batteries.  When you size the battery to get the power you need, you end up with 30 times (give or take) more energy than you actually use for a single pass.  But that is just the nature of batteries.  And, even with that extra energy, it will relate to less than 10 miles or so street range.  A single battery will not let you optimize for both, race and street.

My opinions,

Jeff M







     

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Re: Race Pack vs Street Pack

Morgan LaMoore
On Tue, May 12, 2009 at 4:21 PM, Jeff Major <[hidden email]> wrote:
> The ideal race pack would deliver the required power and have just enough energy for one pass.  That way you don't carry any unused mass with you which slows acceleration.  This seems to be impossible to do with batteries.  When you size the battery to get the power you need, you end up with 30 times (give or take) more energy than you actually use for a single pass.  But that is just the nature of batteries.  And, even with that extra energy, it will relate to less than 10 miles or so street range.  A single battery will not let you optimize for both, race and street.
>
> My opinions,

I think that if you're willing to spend the money on Lithium, you can
find a compromise between range and performance. Yes, there's the
extremes: an A123 pack optimized for racing will have minimal range,
and a Thundersky pack just doesn't have the punch. Other Lithium may
provide a good balance between racing and street use.

For example, Headway cells are much more affordable than A123 but
provide significantly more power than Thundersky. If I had the money,
I would buy enough cells to build a 330V 100Ah Headway pack; I
estimate the cells should weigh about 730 pounds, and it should put
out about 240kW. True, it's much heavier than Killacycle's A123 pack
and it's less powerful, but it's still got plenty of power to have fun
at the track and plenty of range to get there, too.

However, I don't see myself spending $17,000 (plus BMS and charger) on
cells any time soon.

A high-capacity A123 pack would be even more powerful, but I
definitely can't afford that.

Of course, what's enough power or light enough are subjective; it's a
personal decision. I agree that a minimal range A123 pack will provide
the best results for drag racing, but I think that a heavier, higher
capacity pack will be attractive to some people for both racing and
normal use.

-Morgan LaMoore

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Tavrima capacitors

Adrian DeLeon
In reply to this post by Roland Wiench
Roland,

Just checked out the Tavrimas, very cool! Did you get an estimate on  
price? I was thinking about replacing the 48V block in the rear of my  
Cabriolet with lithiums if the price drops a bit (what's the lithium  
equivalent of a T-105, 100AHr?). But if the price is right, replacing the  
3 batteries under the rear seat with a large capacitor might be a better  
option. It's definitely hard to beat the $/mile of lead acid, especially  
if you don't drive many miles per year.

-Adrian

> next battery pack change.  Instead of 260 AH battery pack at 180 volts,  
> I am going to 252 volt pack, using one of the U.S. Battery deep cycle  
> packs at
> 150 AH using one of Tavrima supercapacitors and still be about 600 lbs
> lighter.

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Re: Tavrima capacitors

Roland Wiench
Hello Adrian,

The ESCap 90/300  which is a 300 v at 75kw runs at about $2400.00.  When
running in parallel with the battery pack, the caps will reduce the battery
sag during high ampere discharge.

If you fill out the there form stating all the specifications of your EV,
they could custom build a cap for what you want to do.  Email your EV work
to them and they may even put in there one of there ad.

Roland




----- Original Message -----
From: "Adrian DeLeon" <[hidden email]>
To: "Electric Vehicle Discussion List" <[hidden email]>
Sent: Tuesday, May 12, 2009 6:15 PM
Subject: [EVDL] Tavrima capacitors


> Roland,
>
> Just checked out the Tavrimas, very cool! Did you get an estimate on
> price? I was thinking about replacing the 48V block in the rear of my
> Cabriolet with lithiums if the price drops a bit (what's the lithium
> equivalent of a T-105, 100AHr?). But if the price is right, replacing the
> 3 batteries under the rear seat with a large capacitor might be a better
> option. It's definitely hard to beat the $/mile of lead acid, especially
> if you don't drive many miles per year.
>
> -Adrian
>
> > next battery pack change.  Instead of 260 AH battery pack at 180 volts,
> > I am going to 252 volt pack, using one of the U.S. Battery deep cycle
> > packs at
> > 150 AH using one of Tavrima supercapacitors and still be about 600 lbs
> > lighter.
>
> _______________________________________________
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> Usage guidelines: http://evdl.org/help/index.html#conv
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> Subscription options: http://lists.sjsu.edu/mailman/listinfo/ev
>
>

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Re: Race Pack vs Street Pack

Matt Lacey
In reply to this post by Roland Wiench
An A123 pack will be cheaper to buy, give more power for the same weight
(over the 10 seconds or so) and be of smaller volume than a supercapacitor
(Tavrima, maxwell or otherwise).

An A123 pack will also store 100x more energy for the same weight.

If you want to reduce voltage sag, use an A123 pack, in parrallel.

Matt

-----Original Message-----
From: [hidden email] [mailto:[hidden email]] On Behalf
Of Roland Wiench
Sent: Wednesday, 13 May 2009 2:30 AM
To: Electric Vehicle Discussion List
Subject: Re: [EVDL] Race Pack vs Street Pack

Hello Dave,

What you need is a flux or I mean a supercapacitor that is install parallel
with a lighter weight battery pack.  This is what I am going to do with my
next battery pack change.  Instead of 260 AH battery pack at 180 volts, I am
going to 252 volt pack, using one of the U.S. Battery deep cycle packs at
150 AH using one of Tavrima supercapacitors and still be about 600 lbs
lighter.

My range in a 7010 lb EV at 50% SOC is 69 miles with the 260 AH pack will be
about 62 miles with the 150 AH pack with out the supercapacitor, but the
range and life of the batteries should improve using this device.

See at:  http://www.tavrima.com/home.html

Roland




----- Original Message -----
From: "Dave Delman" <[hidden email]>
To: <[hidden email]>
Sent: Tuesday, May 12, 2009 10:49 AM
Subject: [EVDL] Race Pack vs Street Pack


> Well now that I have the Z2K in the eLectric DeLorean I have to figure out

> a way to get it going faster that 60mph in the quarter mile.  I was
> thinking of going to a higher voltage pack compaired to the thirteen Deka
> 9A31s I have now but it looks like if I use more but smaller 12V batteries

> that my voltage will be higher but my peak current will be lower.
>
> Is there a way to configure a battery pack for maximum range and
> reconfigure it for maximum 1/4 mile speed?
>
> Even if I switch to Li batteries it looks like four 100AH batteries will
> fit in the space of one 9A31.  This doesn't leave much more room than 13 x

> 4 = 52 cells.
>
> Thank you,
>
> Dave Delman
> eLectricdelorean.com
> evalbum.com/1482
>
> _______________________________________________
> 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
>
>

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Re: Race Pack vs Street Pack

gtyler54
In reply to this post by Jeff Major
I did a calculation on the cost of a battery pack, as the required range
drops you can get by with less battery mass, which means you need less
battery capacity, and less mass again. I travel one 3 km to work, allowing
10km it worked out the optimum charge usage was 80%, the pack lasted less
cycles but overall it was cheaper, and you get to have hew packs more often.
It was one of the guys on the EVTECH forum that brought this up first. The
other problem is the power capacity of the pack is also less, I think using
these 16 ahr Hawker batteries, only I don't think they will be sold here in
NZ.


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Re: Tavrima capacitors

dave cover-2
In reply to this post by Roland Wiench
Roland, can you give us some numbers for the pack you plan to match up
with the capacitor?

Thanks

Dave Cover

On Tue, May 12, 2009 at 10:37 PM, Roland Wiench <[hidden email]> wrote:

> Hello Adrian,
>
> The ESCap 90/300  which is a 300 v at 75kw runs at about $2400.00.  When
> running in parallel with the battery pack, the caps will reduce the battery
> sag during high ampere discharge.
>
> If you fill out the there form stating all the specifications of your EV,
> they could custom build a cap for what you want to do.  Email your EV work
> to them and they may even put in there one of there ad.
>
> Roland
>
>
>
>
> ----- Original Message -----
> From: "Adrian DeLeon" <[hidden email]>
> To: "Electric Vehicle Discussion List" <[hidden email]>
> Sent: Tuesday, May 12, 2009 6:15 PM
> Subject: [EVDL] Tavrima capacitors
>
>
>> Roland,
>>
>> Just checked out the Tavrimas, very cool! Did you get an estimate on
>> price? I was thinking about replacing the 48V block in the rear of my
>> Cabriolet with lithiums if the price drops a bit (what's the lithium
>> equivalent of a T-105, 100AHr?). But if the price is right, replacing the
>> 3 batteries under the rear seat with a large capacitor might be a better
>> option. It's definitely hard to beat the $/mile of lead acid, especially
>> if you don't drive many miles per year.
>>
>> -Adrian
>>
>> > next battery pack change.  Instead of 260 AH battery pack at 180 volts,
>> > I am going to 252 volt pack, using one of the U.S. Battery deep cycle
>> > packs at
>> > 150 AH using one of Tavrima supercapacitors and still be about 600 lbs
>> > lighter.
>>
>> _______________________________________________
>> 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
>>
>>
>
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>



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Re: Motor current vs. Pack Current?

Bob Sisson
I have always wondered how the current going into the motor can be different
from the current coming out of the Pack?

The pack is basically a Capacitor/resistor combination and the Motor is
basically a resistor/Inductor combination....  The controller sits between
them and "chops" the current...  but the Total current IN HAS TO equal the
current out...doesn't it?

To that end, is the Battery pack seeing current SPIKES due to the PWM that
make it LOOK like the current is higher...(the current on each individual
slice)... ???

Would a BIG capacitor just before the controller smooth the current from the
pack a bit making it "happier" since it might see lower currents in each
slice, some of the current being filled in from the capacitor???

I am not talking about a PACK of capacitors, but just something big enough
to supply several PWM cycles worth of current or 400A for 1/15,000 of a
second... would the increase the life of the battery enough to justify the
cost of the super capacitor?

Bob Sisson
1993 Geo Metro Convertible Project
Gaithersburg MD

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Re: Motor current vs. Pack Current?

mark at evie-systems
You still have losses inside the controller.  More amps are required
from the pack to overcome those losses, and the motor won't get them.
Are you accounting for those losses?

Bob Sisson wrote:

> I have always wondered how the current going into the motor can be different
> from the current coming out of the Pack?
>
> The pack is basically a Capacitor/resistor combination and the Motor is
> basically a resistor/Inductor combination....  The controller sits between
> them and "chops" the current...  but the Total current IN HAS TO equal the
> current out...doesn't it?
>
> To that end, is the Battery pack seeing current SPIKES due to the PWM that
> make it LOOK like the current is higher...(the current on each individual
> slice)... ???
>
> Would a BIG capacitor just before the controller smooth the current from the
> pack a bit making it "happier" since it might see lower currents in each
> slice, some of the current being filled in from the capacitor???
>
> I am not talking about a PACK of capacitors, but just something big enough
> to supply several PWM cycles worth of current or 400A for 1/15,000 of a
> second... would the increase the life of the battery enough to justify the
> cost of the super capacitor?
>
> Bob Sisson
> 1993 Geo Metro Convertible Project
> Gaithersburg MD
>
> _______________________________________________
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Re: Motor current vs. Pack Current?

Steve Skarda
In reply to this post by Bob Sisson
Amps are not different because of losses, it is because of voltage.  The
inefficiency of the controller is only a very small factor.  The power out
needs to equal the power in minus losses.   The power out is chopped up so
the average motor voltage is much lower than pack voltage.   Watts=amps x
volts.

I haven't tried this with my Zilla for fear of damage to the batteries from
high current, but I imagine that if a person had a controller that exceeded
the capacity of their battery pack, they opened up the amp limits as far as
the controller would allow them to go, and pressed the accelerator to the
floor, the controller might be full on and motor volts and battery volts
would be nearly the same.  In that scenario, amps would be nearly the same
on both sides as well (minus controller losses and voltage drops which I am
not sure you'd even see).

Steve


On Wed, May 13, 2009 at 8:26 AM, Bob Sisson <[hidden email]> wrote:

> I have always wondered how the current going into the motor can be
> different
> from the current coming out of the Pack?
>
> The pack is basically a Capacitor/resistor combination and the Motor is
> basically a resistor/Inductor combination....  The controller sits between
> them and "chops" the current...  but the Total current IN HAS TO equal the
> current out...doesn't it?
>
> To that end, is the Battery pack seeing current SPIKES due to the PWM that
> make it LOOK like the current is higher...(the current on each individual
> slice)... ???
>
> Would a BIG capacitor just before the controller smooth the current from
> the
> pack a bit making it "happier" since it might see lower currents in each
> slice, some of the current being filled in from the capacitor???
>
> I am not talking about a PACK of capacitors, but just something big enough
> to supply several PWM cycles worth of current or 400A for 1/15,000 of a
> second... would the increase the life of the battery enough to justify the
> cost of the super capacitor?
>
> Bob Sisson
> 1993 Geo Metro Convertible Project
> Gaithersburg MD
>
> _______________________________________________
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Re: Motor current vs. Pack Current?

Jeff Major
In reply to this post by Bob Sisson

--- On Wed, 5/13/09, Bob Sisson <[hidden email]> wrote:

> I have always wondered how the current going into the motor
> can be different
> from the current coming out of the Pack?

Hi Bob,

The motor controller is a Buck Converter where the output inductor is in the load (motor).  A Buck Converter consists of 4 primary components, a switch (mosfet or the like), a diode, a capacitor, and an inductor.  The capacitor is across the input and the inductor is in series with the output (inside the motor in this case).  The switch is between the capacitor and inductor and the diode is across the inductor and load (motor).

The diode (called a freewheeling diode) supports load current during the off time of the switch.  This allows for what is called current multiplication.  With this Buck motor controller, the motor current is always greater than the source current, except when it is at 0 percent duty cycle or at 100 percent duty cycle.  Then the input and output currents are equal.

>
> Would a BIG capacitor just before the controller smooth the
> current from the
> pack a bit making it "happier" since it might see
> lower currents in each
> slice, some of the current being filled in from the
> capacitor???
>

These capacitors are included inside the controller.  No need to add more.  In fact, that can be detrimental.

There is plenty of literature on Buck Converters and motor controllers out there.  Do a search and you should be able to find tutorial sites.

Regards,

Jeff M




     

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Re: Motor current vs. Pack Current?

Morgan LaMoore
In reply to this post by Bob Sisson
It's the motor's inductance that allows this. Say your pack is 100V
and the motor needs 50V at a certain speed.

While the controller transistor is on, full motor current flows from
the batteries through the motor. The motor only needs 50V for back
EMF; the extra energy is stored in the inductance.

Then the transistor turns off. The motor inductance forces current to
keep flowing; there's 0A from the batteries and 0A to the motor, but
the back EMF is still 50V; the motor inductance sees -50V and releases
its stored energy to keep the current flowing and keep generating
torque.

The controller does this at about 20kHz so the averaging makes
everything seem like DC.

The controller also has a big capacitor bank in parallel with the
battery; this helps protect the controller from voltage spikes and
makes the battery see more of a DC current and smaller current spikes.

I hope this helps someone's understanding of controllers.

-Morgan LaMoore

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Re: Tavrima capacitors

Roland Wiench
In reply to this post by dave cover-2
Hello Dave,

The battery choices are either 30 each US-145 XC for 180 V pack at 251 AH at
154 mins @ 75 amps which would weigh 2160 lbs and have a range of 61 miles.
There would be no room for the supercapacitor.

The next battery choice is 30 each US-8VGCHC XC for 240 V pack at 183 AH at
95 mins @ 75 amps which would weigh 2070 lbs and have a range of 58 miles.
There would be no room for the supercapacitor.

The next battery choice is 23 each US-8VGCHC XC for 184 V pack at 183 AH at
95 mins @ 75 amps which would weigh 1587 lbs and have a range of 51 miles.
There would be no room for the supercapacitor.

The next battery choice is 21 each US-12V XC for 252 V pack at 155 AH at 77
mins @ 75 amps which would weigh 1795.5 lbs and have a range of 62.5 miles.
There would be no room for the supercapacitor.

The next battery choice is 18 each US-12V XC for 216 V pack at 155 AH at 77
mins @ 75 amps and would weigh 1611 lbs and have a range of 53.5 miles.
There is now room for a supercapacitor.

The last battery choice is 18 each US-EV 145 XC for 216 V pack at 145 AH at
72 mins @ 75 amps and would weigh 1546 lbs and have a range of  51.3 miles.
There is now room for a supercapacitor.

All these U.S. Batteries come with the large L battery post.  Can not get
these types with a Trojan battery.

Note:  These range estimates are consider at a constant 75 battery amps and
not allowing for the increase battery ampere for stop and acceleration back
up to speed.  The supercapacitor will keep the batteries at a more constant
battery ampere, while the capacitor will discharge the higher ampere during
the acceleration.

The batteries choices that use with the supercapacitor should improve in
range and life of the battery.

If the supercapacitor is connected in parallel with the battery pack and you
only use one volt and amp indication, you will not be able to tell what the
status of the battery and the capacitor is doing.

What I plan to do is to connected the negative side of the capacitor
directly to the negative side of the battery pack.  The positive side of the
capacitor will be fuse with a 400 amp Buss Limitron fuse that can take a
short time surge well over 2000 amps.

The fuse is than connected to a 600 amp contactor that is also rated for
2000 amp surge.  A amp meter shunt is then connected to the output of the
contactor and then is connected ahead of the E-meter shunt, so now the
E-meter now only reads the battery voltage and ampere and the capacitor
reads a separate voltage and ampere.

When the ignition switch is turn to the ignition ON position, it then turns
on a small 12 volt isolated relay that then turns on the contactor for the
supercapacitor.

There will be a 1 pole 3 position selector switch in the 12 volt control
line to this capacitor contactor.  It will be use to turn on the contactor
to connect the capacitor in parallel with the batteries during charging.

You also want the capacitor to be disconnected from the batteries when doing
maintenance on any one of the battery links.  You do not want to cause a
high sparking discharge.  Also you do not want the capacitor in the same
compartment as the batteries.  I plan to put in a seal off compartment for
this device.

Roland




----- Original Message -----
From: "dave cover" <[hidden email]>
To: "Electric Vehicle Discussion List" <[hidden email]>
Sent: Wednesday, May 13, 2009 5:06 AM
Subject: Re: [EVDL] Tavrima capacitors


Roland, can you give us some numbers for the pack you plan to match up
with the capacitor?

Thanks

Dave Cover

On Tue, May 12, 2009 at 10:37 PM, Roland Wiench <[hidden email]> wrote:

> Hello Adrian,
>
> The ESCap 90/300 which is a 300 v at 75kw runs at about $2400.00. When
> running in parallel with the battery pack, the caps will reduce the
> battery
> sag during high ampere discharge.
>
> If you fill out the there form stating all the specifications of your EV,
> they could custom build a cap for what you want to do. Email your EV work
> to them and they may even put in there one of there ad.
>
> Roland
>
>
>
>
> ----- Original Message -----
> From: "Adrian DeLeon" <[hidden email]>
> To: "Electric Vehicle Discussion List" <[hidden email]>
> Sent: Tuesday, May 12, 2009 6:15 PM
> Subject: [EVDL] Tavrima capacitors
>
>
>> Roland,
>>
>> Just checked out the Tavrimas, very cool! Did you get an estimate on
>> price? I was thinking about replacing the 48V block in the rear of my
>> Cabriolet with lithiums if the price drops a bit (what's the lithium
>> equivalent of a T-105, 100AHr?). But if the price is right, replacing the
>> 3 batteries under the rear seat with a large capacitor might be a better
>> option. It's definitely hard to beat the $/mile of lead acid, especially
>> if you don't drive many miles per year.
>>
>> -Adrian
>>
>> > next battery pack change. Instead of 260 AH battery pack at 180 volts,
>> > I am going to 252 volt pack, using one of the U.S. Battery deep cycle
>> > packs at
>> > 150 AH using one of Tavrima supercapacitors and still be about 600 lbs
>> > lighter.
>>
>> _______________________________________________
>> 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
>>
>>
>
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>
>



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Re: Tavrima capacitors

dave cover-2
Roland

I'm asking so I can understand how all this works. Now, it looks like
you are only considering the capacitor with a 216 volt pack. Is this
only due to physical limitations? Space available?

I thought I'd read about people using two different chemistry packs
together, one with high amp hours and low discharge rate and another
with low amphours but high discharge. As the high AH pack sags during
heavy acceleration the other helps out. The voltage of the helper pack
is usually a little lower than the main pack. And I thought the same
general theory applied to capacitors.

So my question is, how does a 300v capacitor with a 216 volt pack? How
do you calculate the correct capacitor for a given pack size?

Thanks

Dave Cover

On Wed, May 13, 2009 at 10:26 AM, Roland Wiench <[hidden email]> wrote:

> Hello Dave,
>
> The battery choices are either 30 each US-145 XC for 180 V pack at 251 AH at
> 154 mins @ 75 amps which would weigh 2160 lbs and have a range of 61 miles.
> There would be no room for the supercapacitor.
>
> The next battery choice is 30 each US-8VGCHC XC for 240 V pack at 183 AH at
> 95 mins @ 75 amps which would weigh 2070 lbs and have a range of 58 miles.
> There would be no room for the supercapacitor.
>
> The next battery choice is 23 each US-8VGCHC XC for 184 V pack at 183 AH at
> 95 mins @ 75 amps which would weigh 1587 lbs and have a range of 51 miles.
> There would be no room for the supercapacitor.
>
> The next battery choice is 21 each US-12V XC for 252 V pack at 155 AH at 77
> mins @ 75 amps which would weigh 1795.5 lbs and have a range of 62.5 miles.
> There would be no room for the supercapacitor.
>
> The next battery choice is 18 each US-12V XC for 216 V pack at 155 AH at 77
> mins @ 75 amps and would weigh 1611 lbs and have a range of 53.5 miles.
> There is now room for a supercapacitor.
>
> The last battery choice is 18 each US-EV 145 XC for 216 V pack at 145 AH at
> 72 mins @ 75 amps and would weigh 1546 lbs and have a range of  51.3 miles.
> There is now room for a supercapacitor.
>
> All these U.S. Batteries come with the large L battery post.  Can not get
> these types with a Trojan battery.
>
> Note:  These range estimates are consider at a constant 75 battery amps and
> not allowing for the increase battery ampere for stop and acceleration back
> up to speed.  The supercapacitor will keep the batteries at a more constant
> battery ampere, while the capacitor will discharge the higher ampere during
> the acceleration.
>
> The batteries choices that use with the supercapacitor should improve in
> range and life of the battery.
>
> If the supercapacitor is connected in parallel with the battery pack and you
> only use one volt and amp indication, you will not be able to tell what the
> status of the battery and the capacitor is doing.
>
> What I plan to do is to connected the negative side of the capacitor
> directly to the negative side of the battery pack.  The positive side of the
> capacitor will be fuse with a 400 amp Buss Limitron fuse that can take a
> short time surge well over 2000 amps.
>
> The fuse is than connected to a 600 amp contactor that is also rated for
> 2000 amp surge.  A amp meter shunt is then connected to the output of the
> contactor and then is connected ahead of the E-meter shunt, so now the
> E-meter now only reads the battery voltage and ampere and the capacitor
> reads a separate voltage and ampere.
>
> When the ignition switch is turn to the ignition ON position, it then turns
> on a small 12 volt isolated relay that then turns on the contactor for the
> supercapacitor.
>
> There will be a 1 pole 3 position selector switch in the 12 volt control
> line to this capacitor contactor.  It will be use to turn on the contactor
> to connect the capacitor in parallel with the batteries during charging.
>
> You also want the capacitor to be disconnected from the batteries when doing
> maintenance on any one of the battery links.  You do not want to cause a
> high sparking discharge.  Also you do not want the capacitor in the same
> compartment as the batteries.  I plan to put in a seal off compartment for
> this device.
>
> Roland
>
>
>
>
> ----- Original Message -----
> From: "dave cover" <[hidden email]>
> To: "Electric Vehicle Discussion List" <[hidden email]>
> Sent: Wednesday, May 13, 2009 5:06 AM
> Subject: Re: [EVDL] Tavrima capacitors
>
>
> Roland, can you give us some numbers for the pack you plan to match up
> with the capacitor?
>
> Thanks
>
> Dave Cover
>
> On Tue, May 12, 2009 at 10:37 PM, Roland Wiench <[hidden email]> wrote:
>> Hello Adrian,
>>
>> The ESCap 90/300 which is a 300 v at 75kw runs at about $2400.00. When
>> running in parallel with the battery pack, the caps will reduce the
>> battery
>> sag during high ampere discharge.
>>
>> If you fill out the there form stating all the specifications of your EV,
>> they could custom build a cap for what you want to do. Email your EV work
>> to them and they may even put in there one of there ad.
>>
>> Roland
>>
>>
>>
>>
>> ----- Original Message -----
>> From: "Adrian DeLeon" <[hidden email]>
>> To: "Electric Vehicle Discussion List" <[hidden email]>
>> Sent: Tuesday, May 12, 2009 6:15 PM
>> Subject: [EVDL] Tavrima capacitors
>>
>>
>>> Roland,
>>>
>>> Just checked out the Tavrimas, very cool! Did you get an estimate on
>>> price? I was thinking about replacing the 48V block in the rear of my
>>> Cabriolet with lithiums if the price drops a bit (what's the lithium
>>> equivalent of a T-105, 100AHr?). But if the price is right, replacing the
>>> 3 batteries under the rear seat with a large capacitor might be a better
>>> option. It's definitely hard to beat the $/mile of lead acid, especially
>>> if you don't drive many miles per year.
>>>
>>> -Adrian
>>>
>>> > next battery pack change. Instead of 260 AH battery pack at 180 volts,
>>> > I am going to 252 volt pack, using one of the U.S. Battery deep cycle
>>> > packs at
>>> > 150 AH using one of Tavrima supercapacitors and still be about 600 lbs
>>> > lighter.
>>>
>>> _______________________________________________
>>> 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
>>>
>>>
>>
>> _______________________________________________
>> 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
>>
>>
>
>
>
> --
> http://www.evalbum.com/2149
>
> _______________________________________________
> General EVDL support: http://evdl.org/help/
> Usage guidelines: http://evdl.org/help/index.html#conv
> Archives: http://evdl.org/archive/
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>
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> Subscription options: http://lists.sjsu.edu/mailman/listinfo/ev
>
>



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Re: Tavrima capacitors

Roland Wiench
Hello Dave,

A capacitor that is rated at 300 volts is the maximum volt rating of the
capacitor.  The 216 volt battery when charge at a equalization charge is
280.08 volts.  So that is still below the capacitor rating.

If you charge a 12 volt battery to 15 volts, then this type of capacitor in
parallel will be also charge at 15 volts.

Yes, the size of that battery or any other type that has the same cubic
space, will allow for me in install seal fiberglass compartment in the
battery box to contain the capacitor plus the other components and room for
a BMS system and battery monitor units.

Roland


----- Original Message -----
From: "dave cover" <[hidden email]>
To: "Electric Vehicle Discussion List" <[hidden email]>
Sent: Wednesday, May 13, 2009 7:51 AM
Subject: Re: [EVDL] Tavrima capacitors


Roland

I'm asking so I can understand how all this works. Now, it looks like
you are only considering the capacitor with a 216 volt pack. Is this
only due to physical limitations? Space available?

I thought I'd read about people using two different chemistry packs
together, one with high amp hours and low discharge rate and another
with low amphours but high discharge. As the high AH pack sags during
heavy acceleration the other helps out. The voltage of the helper pack
is usually a little lower than the main pack. And I thought the same
general theory applied to capacitors.

So my question is, how does a 300v capacitor with a 216 volt pack? How
do you calculate the correct capacitor for a given pack size?

Thanks

Dave Cover

On Wed, May 13, 2009 at 10:26 AM, Roland Wiench <[hidden email]> wrote:

> Hello Dave,
>
> The battery choices are either 30 each US-145 XC for 180 V pack at 251 AH
> at
> 154 mins @ 75 amps which would weigh 2160 lbs and have a range of 61
> miles.
> There would be no room for the supercapacitor.
>
> The next battery choice is 30 each US-8VGCHC XC for 240 V pack at 183 AH
> at
> 95 mins @ 75 amps which would weigh 2070 lbs and have a range of 58 miles.
> There would be no room for the supercapacitor.
>
> The next battery choice is 23 each US-8VGCHC XC for 184 V pack at 183 AH
> at
> 95 mins @ 75 amps which would weigh 1587 lbs and have a range of 51 miles.
> There would be no room for the supercapacitor.
>
> The next battery choice is 21 each US-12V XC for 252 V pack at 155 AH at
> 77
> mins @ 75 amps which would weigh 1795.5 lbs and have a range of 62.5
> miles.
> There would be no room for the supercapacitor.
>
> The next battery choice is 18 each US-12V XC for 216 V pack at 155 AH at
> 77
> mins @ 75 amps and would weigh 1611 lbs and have a range of 53.5 miles.
> There is now room for a supercapacitor.
>
> The last battery choice is 18 each US-EV 145 XC for 216 V pack at 145 AH
> at
> 72 mins @ 75 amps and would weigh 1546 lbs and have a range of 51.3 miles.
> There is now room for a supercapacitor.
>
> All these U.S. Batteries come with the large L battery post. Can not get
> these types with a Trojan battery.
>
> Note: These range estimates are consider at a constant 75 battery amps and
> not allowing for the increase battery ampere for stop and acceleration
> back
> up to speed. The supercapacitor will keep the batteries at a more constant
> battery ampere, while the capacitor will discharge the higher ampere
> during
> the acceleration.
>
> The batteries choices that use with the supercapacitor should improve in
> range and life of the battery.
>
> If the supercapacitor is connected in parallel with the battery pack and
> you
> only use one volt and amp indication, you will not be able to tell what
> the
> status of the battery and the capacitor is doing.
>
> What I plan to do is to connected the negative side of the capacitor
> directly to the negative side of the battery pack. The positive side of
> the
> capacitor will be fuse with a 400 amp Buss Limitron fuse that can take a
> short time surge well over 2000 amps.
>
> The fuse is than connected to a 600 amp contactor that is also rated for
> 2000 amp surge. A amp meter shunt is then connected to the output of the
> contactor and then is connected ahead of the E-meter shunt, so now the
> E-meter now only reads the battery voltage and ampere and the capacitor
> reads a separate voltage and ampere.
>
> When the ignition switch is turn to the ignition ON position, it then
> turns
> on a small 12 volt isolated relay that then turns on the contactor for the
> supercapacitor.
>
> There will be a 1 pole 3 position selector switch in the 12 volt control
> line to this capacitor contactor. It will be use to turn on the contactor
> to connect the capacitor in parallel with the batteries during charging.
>
> You also want the capacitor to be disconnected from the batteries when
> doing
> maintenance on any one of the battery links. You do not want to cause a
> high sparking discharge. Also you do not want the capacitor in the same
> compartment as the batteries. I plan to put in a seal off compartment for
> this device.
>
> Roland
>
>
>
>
> ----- Original Message -----
> From: "dave cover" <[hidden email]>
> To: "Electric Vehicle Discussion List" <[hidden email]>
> Sent: Wednesday, May 13, 2009 5:06 AM
> Subject: Re: [EVDL] Tavrima capacitors
>
>
> Roland, can you give us some numbers for the pack you plan to match up
> with the capacitor?
>
> Thanks
>
> Dave Cover
>
> On Tue, May 12, 2009 at 10:37 PM, Roland Wiench <[hidden email]> wrote:
>> Hello Adrian,
>>
>> The ESCap 90/300 which is a 300 v at 75kw runs at about $2400.00. When
>> running in parallel with the battery pack, the caps will reduce the
>> battery
>> sag during high ampere discharge.
>>
>> If you fill out the there form stating all the specifications of your EV,
>> they could custom build a cap for what you want to do. Email your EV work
>> to them and they may even put in there one of there ad.
>>
>> Roland
>>
>>
>>
>>
>> ----- Original Message -----
>> From: "Adrian DeLeon" <[hidden email]>
>> To: "Electric Vehicle Discussion List" <[hidden email]>
>> Sent: Tuesday, May 12, 2009 6:15 PM
>> Subject: [EVDL] Tavrima capacitors
>>
>>
>>> Roland,
>>>
>>> Just checked out the Tavrimas, very cool! Did you get an estimate on
>>> price? I was thinking about replacing the 48V block in the rear of my
>>> Cabriolet with lithiums if the price drops a bit (what's the lithium
>>> equivalent of a T-105, 100AHr?). But if the price is right, replacing
>>> the
>>> 3 batteries under the rear seat with a large capacitor might be a better
>>> option. It's definitely hard to beat the $/mile of lead acid, especially
>>> if you don't drive many miles per year.
>>>
>>> -Adrian
>>>
>>> > next battery pack change. Instead of 260 AH battery pack at 180 volts,
>>> > I am going to 252 volt pack, using one of the U.S. Battery deep cycle
>>> > packs at
>>> > 150 AH using one of Tavrima supercapacitors and still be about 600 lbs
>>> > lighter.
>>>
>>> _______________________________________________
>>> 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
>>>
>>>
>>
>> _______________________________________________
>> 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
>>
>>
>
>
>
> --
> http://www.evalbum.com/2149
>
> _______________________________________________
> 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
>
> _______________________________________________
> 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
>
>



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Re: Tavrima capacitors

drdhdmd
In reply to this post by Adrian DeLeon
How does one calculate the size of a super cap in farads needed to go 1/4
mile and supply 2000 amps at 240v for say 20 seconds?

Dave Delman
eLectricDeLorean.com**************Dell Mini Netbooks: Great deals starting
at $299 after instant savings!
(<a href="http://pr.atwola.com/promoclk/100126575x1221972443x1201442012/aol?redir=http:%2F%2Fad.doubleclick.net%2Fclk%3B214819441%3">http://pr.atwola.com/promoclk/100126575x1221972443x1201442012/aol?redir=http:%2F%2Fad.doubleclick.net%2Fclk%3B214819441%3
B36680237%3Bi)

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Re: Motor current vs. Pack Current?

Phil Marino-2
In reply to this post by Jeff Major
Jeff
I always thought that more input capacitance in a controller was always
better.  More capacitance means the controller sees a more constant voltage
power source, and the batteries would see a more constant voltage (and
constant current) load with lower current spikes.  What kind of problems can
more input capacitance cause?

Thanks, Phil

On Wed, May 13, 2009 at 10:03 AM, <[hidden email]> wrote:

>
> --- On Wed, 5/13/09, Bob Sisson <[hidden email]> wrote:
>
> > I have always wondered how the current going into the motor
> > can be different
> > from the current coming out of the Pack?
>
>
> >
>
> These capacitors are included inside the controller.  No need to add more.
> In fact, that can be detrimental.
>
>
> Regards,
>
> Jeff M
>
>
>
>
>
>
> _______________________________________________
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