ultracapacitors and batteries

beenthere

Joined Apr 20, 2004
15,819
Look at post #3:
from these numbers I believe as the capacitors drain at 600 amps the batteries will be filling the ucaps back up. at 17.4 milliohms the batteries would be able to fill the caps and not see over 200 amps.
The mechanism for lowering the current supplied by the battery pack by 1/3 is not obvious. Especially as the supercaps are supposed to be supplying 600 amps.

If the OP could clarify the meaning of this entire post
I know the batteries will still be charging the capacitors but not at 600 amps. the question I am trying to get is what will the batteries see as far as amperage charging the capacitors actually equalizing with the capacitors once the capacitors are drained and have yet to get an answer.

maybe because the answer cannot be calculated? that would make sense.

other reason is there are EVs that have capacitors and they are seeing the peukert effect eliminated. They only have the capacitors in parallel with the batteries. I am working with an EV owner that would like to see how this works with the capacitors in series that has capacitors in parallel, so before I wire things up Id like to see if the outcome can be calculated.
it would be most helpful.

Is there a link about the EV's that have had the Peukert effect eliminated?
 

steveb

Joined Jul 3, 2008
2,436
Is there a link about the EV's that have had the Peukert effect eliminated?
Clearly, the effect can't be eliminated, but it can be reduced in applications where there are pulsed power needs. From data I've looked at, the Peukert effect seems to be less severe in the newer lithium based battery systems, so this may not be a primary focus of research. However, the ability of the caps to supply current surges is helpful for most battery types, simply due to the source resistance effects which cause voltage dipping in batteries. Still, the OP is interested in lead acid, so the Peukert effect may be relevant in his application.

The OP has explained that one issue is starting from zero speed, which places the large current load on the system. If zero speed starting happens often, but with sufficient time to charge caps in between, and if the current draw at normal speeds is much lower than when starting, then a hybrid use of caps and batts should greatly improve battery efficiency because the peak current draw on the battery will be much less. The key question is how to configure the system topology to realize the maximum improvement. This is not trivial to figure out and will likely depend on the actual power loading profile after starting.

The use of a DC/DC converter with fast feedback control allows an optimum topology to be realized, but this comes at the expense of the DC/DC converter efficiency, which will at least partially offset any possible efficiency improvement. The use of parallel or series arrangements with switching in and out based on conditions, is worth thinking about to see if reliability, efficiency and simplicity can be maximized. This is not a trivial problem; hence, experiments, modeling and good thinking are likely needed to work this out.
 
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beenthere

Joined Apr 20, 2004
15,819
A flywheel might be able to aid in reducing the start-up draw by coupling through a torque converter, but how much extra crud can you pack into a vehicle and manage to keep weight down for efficiency?
 

Thread Starter

michaeljayclark

Joined Mar 13, 2011
16
The topology is the most important factor. I have thought of different ways to accomplish the goal without making the circuit to complicated.

the AFS trinity has a system in place that the vehicle will use capacitors to accelerate to cruising speed then switch to batteries. the caps will be recharged by regen or from the batteries.

my system will have the caps recharged by the batteries OR by an onboard generator. the onboard generator will only be used when the travels of the day take me beyond the pure ev range of the vehicle. I can add in regen and may do so.

in this thread on diyelectriccar.com

http://www.diyelectriccar.com/forums/showthread.php?t=26137&highlight=capacitor+voltage

the OP experienced a noticeable difference when capacitors were wired in by parallel. he noticed the truck had better take off. the time to reach cruising speed wasnt increased but the voltage sag was almost eliminated. I am guessing the batteries were not new and therefore were giving the truck some trouble on takeoff before the capacitors were added. these capacitors were not ultracapacitors.

http://web.ing.puc.cl/~power/paperspdf/dixon/42a.pdf

http://www.labplan.ufsc.br/congressos/Powertech/papers/385.pdf

http://web.ing.puc.cl/~power/paperspdf/dixon/58a.pdf

http://eeeic.org/proc/papers/28.pdf

some good papers on tests with ultracaps. all want to use a dc to dc converter. a dc to dc converter that is able to handle high current isnt really available. if anyone finds one, please let me know!

my purpose is to discover a way through topology to get the benefit of the ultracaps without a converter. the first experiment i want to try is to have the caps in series between the batteries and the controller. a shunt will measure the amperage passed from the caps to the controller and a second shunt will be placed between the batteries and capacitors to measure the amperage.

i want to see how many amps the caps pull from the batteries while the caps are sending energy to the controller. my theory here is the caps will handle the rush of power the controller demands and drain until the vehicle reaches cruising speed. The caps will never fully drain. a calculation by the tecate sizing tool shows the caps can have a 600 amp draw and not run out of voltage until after 11 seconds. The vehicle will be up to its top speed in 11 seconds I am guessing (experiments will show this) so the batteries will not see empty caps to fill and surge to fill them.

the second experiment will be made with the caps and batts in parallel.

DEKA has told me they are testing a battery that has a ultracapacitor within the case. they are using them to level out peak load for power plants. their first test will be with the power substation at their east pen manufacturing plant. this would mean the batteries and capacitors could be in series and a batt - cap - batt - cap -batt- cap etc topology.

It seems the car stereo industry is already doing this with capacitors on the batteries in hybrid form.

I emailed MAXWELL to see how they feel about having all caps and batts in series. they have not responded yet.
 

shortbus

Joined Sep 30, 2009
10,045
Stop accusing the OP of trying to get something for nothing. He has made it clear that this is not his goal. He is trying to improve efficiency by combining caps and batts which is possible in some applications. If you believe this application is not one of them, then stick to that fact. If you believe his approach is not effective, then stick to that issue. If you have another point, then make it without a false accusation. This type of accusation is quite insulting to most members here.
I'm not accusing the O/P of anything, just reading what he is saying. Have you read this thread from the start? Have you read the same type of thread the O/P posted on ETO?

If he is charging the caps from the batteries he is depleting the batteries, nothing more nothing less. Every time you convert energy from one form to another you loose a certain part of that energy in the process. If you don't it's over-unity.

To get the same amount of energy out of a capacitor that you put in is not possible. There is a loss. The O/P keeps talking about putting 200 amps into his caps to get 600 amps out to his motor. What is that other than over-unity????

I apologize if you can show how I am making claims that he is not, but show me first.
 

steveb

Joined Jul 3, 2008
2,436
I'm not accusing the O/P of anything, just reading what he is saying. Have you read this thread from the start? Have you read the same type of thread the O/P posted on ETO?
Yes, I read the thread from the start, a few times now. No I have not read what the O/P posted at ETO, but I don't view it as relevant to what we say here anyway. If you do think something there is relevant then you can link to it, or quote from it.

If he is charging the caps from the batteries he is depleting the batteries, nothing more nothing less. Every time you convert energy from one form to another you loose a certain part of that energy in the process. If you don't it's over-unity.
If the energy lost in conversion is less than the heat lost doing it the other way then there is the possibility of having better use of the available energy with a hybrid approach. Proposing to waste less energy as heat is not an over-unity claim, it is an engineering concern.

To get the same amount of energy out of a capacitor that you put in is not possible. There is a loss. The O/P keeps talking about putting 200 amps into his caps to get 600 amps out to his motor. What is that other than over-unity????
That is not overunity in itself, unless you impose more constraints. You can charge caps up at 200 A and discharge at 600 A all day long, if you like. There is no problem with this. Certainly, you lose energy in the process, but that's no problem if this lets you increase efficiency somewhere else. Your claim that is this overunity is simply not correct.

I did a quick calculation using the specs for these capacitors, and it seems that, in terms of energy, they are 90 % efficient charging at 200 A and 65 % efficient discharging at 600 A. Those are significant losses and if a DC/DC converter is used, even lower efficiency is obtained. Still, these numbers would need to be compared to the battery losses at high current which would be much higher. In some cases the numbers may not work out favorably, but in many applications where there are severe peak loading conditions (such as with vehicles !!!) there is an advantage. And, even if the application does not match the use of the idea, that is not a basis to accuse someone trying to achieve over-unity. It would simply be a case of the numbers not working out for the application and expected typical load profiles.

I apologize if you can show how I am making claims that he is not, but show me first.
I'm not asking you to apologize. I'm just asking you to stop putting an incorrect label on the OP and the subject matter of the thread.

There are hundreds of companies and hundreds of research papers addressing work in the area of using a hybrid capacitor/battery approach to improve system efficiency. They are all based on exactly the types of ideas the OP mentioned: Peukert Effect and source resistance effects, and other non-ideal aspects of battery operation.

The fact that this is a scientifically accepted research area is all the basis I need to ask you to allow the discussion without engaging in McCarthyism against a member of the forum. That is the standard used to determine suitable material in a forum like this. If you are opposed to the idea on scientific grounds, you should be publishing a paper and fighting the idea in that public arena.
 
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Thread Starter

michaeljayclark

Joined Mar 13, 2011
16
yes, the 600 amps has to be replaced into the capacitors. the batteries will replace the 600 amps but at a slower rate.

"Manufacturers rate the capacity of a battery with reference to a discharge time. For example, a battery might be rated at 100 A·h when discharged at a rate that will fully discharge the battery in 20 hours. In this example, the discharge current would be 5 amperes. If the battery is discharged in a shorter time, with a higher current, the delivered capacity is less. Peukert's law describes an exponential relationship between the discharge current (normalized to some base rated current) and delivered capacity (nomalized to the rated capacity), over some specified range of discharge currents. If the exponent constant was one, the delivered capacity would be independent of the current. For a lead-acid battery however, the value of k is typically between 1.1 and 1.3. The Peukert constant varies according to the age of the battery, generally increasing with age. Application at low discharge rates must take into account the battery self-drain current. At very high currents, practical batteries will give even less capacity than predicted from a fixed exponent. The equation does not allow for the effect of varying temperature on battery capacity." from wikipedia.

this is what I am changing with the use of capacitors. Lowering the high amperage draw from the battery and allowing it to fully give the 235 amp hours it is rated at.

under constant heavy drain the batteries will deliver less than 235 amp hours. If I keep the drain below 200 amps, and 100 amps ideally I can get the full amp hours.

wording it like i want to get 600 amps from the capacitors and only fill it with 200 looks like i want to do perpetual motion.

I want to get 600 amps out of the capacitors and then replace that 600 amps at a discharge rate that will not overheat the battery and then the battery can deliver all 235 amp hours, not lose amp hours by peukerts law.
 

Thread Starter

michaeljayclark

Joined Mar 13, 2011
16
I received an email from a maxwell engineer about placing the caps between the battery pack and motor controller:

"As far as I know, the danger of series connecting the caps with any other source is the possibility of charging the caps in the reverse direction, unless the user has extensive electronic controls to prevent that.
In this case, placing the caps in series with batteries may not be helpful as the batteries will be subject to the same large currents that the caps are expected to handle, which would probably defeat the original purpose. "

makes perfect sense and is a definite answer to my question. The answer also points out other items I didnt think of. The fact that if the batteries drain the caps in anyway then the caps would be discharge or charge in reverse and be damaged. My guess to try to correct that roughly would be a very large diode. ok, crudely and very inefficient and may not work anyway.

I did think that when the caps are discharged under a heavy load the batteries would simply send energy through the caps to the controller and see the same over 200 amps discharge. I was thinking that the caps wouldnt fully discharge and the batteries wouldnt have to pass energy through the caps to the motor controller. When the caps drain down the batteries would be filling the caps back up at the same amperage rate the caps are sending according to that answer. that was a major question I had.

I have seen a formula that showed the caps may bottleneck the energy if the batteries have to supply energy to the motor controller when the caps cannot.

therefore the answer of whether the caps can be in series with the batteries is no. Another topology has to be looked at. finally an answer that has facts behind it. thats what I am looking for in these discussions. Another reason I am asking these questions is to have the answers available to all in google searches. the more complete the answer the better the understanding. I believe the entire reason for the forums is for people to learn more about the subject the forum is based on. when people need to learn about electric cars, they go to forums like diyelectriccar.com and do searches. if the answer doesnt show up in the search results, then post the question.

Having the caps in parallel is the simplest way here. But the caps will not get 100% utilized. The idea of the caps being separated from the batteries for take off then recharged another way should be the answer unless the other recharging method is a generator and the vehicle is a series hybrid. I like the idea of having an EV mode and a Series Hybrid mode just like the chevrolet volt and plug in prius plus other plug ins coming on the market.

a motor controller could be of use here. a controller that can handle 100 amps is not that expensive. the battery pack would be 144 volts. i want to only send the max of 100 amps to the caps. the motor controller can treat the caps as a motor and be able to send only 100 amps into the caps from the battery pack. the pot box normally used for acceleration could control the amount of amperage that goes from the batteries to the caps. A small actuator could open up the pot box circuit just like pressing the pedal to accelerate, then close when the caps are full. with the low esr of the caps this could be achieved pretty quickly.

I asked about using the caps to launch a vehicle, recharge them with a generator and be ready to launch again. the answer I got was 144 volts of 3000 farad caps and a 13 kw generator. this could launch a 5000 pound vehicle to 55 and then by the time it stopped the caps would be full again.

I welcome all responses positive or negative. Ive been called an idiot many times. I still keep asking till I find a person that is willing to look at the idea and give their opinion on the project and give me an answer with facts behind it so I understand better. When I find an answer I try to get other answers from other sources to compare. In this situation I have seen caps in cars and they work but yet I get answers all the time that say they dont work. Id just like to have other ideas of how to integrate caps into cars that would utilize the ucaps better.
 

steveb

Joined Jul 3, 2008
2,436
In this case, placing the caps in series with batteries may not be helpful as the batteries will be subject to the same large currents that the caps are expected to handle, which would probably defeat the original purpose. "

makes perfect sense and is a definite answer to my question.
The series approach does seem limited for your application, and the Maxwell engineer also pointed out some practical complications. Still, you are wise to try and brainstorm and think about all options. I have seen examples where people do try the series combination, although the preference was to buffer the capacitor energy through a DC/DC converter for more control of the series applied voltage. The basic idea here is to compensate for the voltage sag due to the high currents.

Still, the parallel approach is more efficient in principle because preventing the batteries from needing to deliver high currents prevents the severe voltage sag and improves the Peukert limitations, as you've said. To gain the best advantages of the parallel arrangement, a DC/DC converter, set up to provide nearly constant current draw on the battery, is very effective. The issues are that DC/DC converters have about 85% efficiency, and there is the complexity of needing high current/voltage transtors (MOSFETs IGBTs etc) and good control circuits (microprocessor based preferably) and good algorithms (software).
 
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steveb

Joined Jul 3, 2008
2,436
Another point that can be brought up is the poor low temperature performance of batteries in general. Although, super-caps do have slight specification degradation at low temperature (lower capacitance and higher source resistance), they are relativley insensitive to temperature change compared to batteries. If an application has a low temperature spec, the capacitors are more likely to be helpful.

Similarly, the capacitors may be more helpful toward the end of life of the battery when it's capabilities are significantly degraded compared to a new one. Also, the use of the capacitors can reduce the stress on the battery and extend the useful life of the battery itself.

I can't stress enough just how difficult it can be to navigate through the full design space of these applications. If this were my project, I would do exactly as you are and ask for as much brainstorming information as possible.
 

nsaspook

Joined Aug 27, 2009
13,086
The ultra-cap connection is in series with the DC/DC converter on the MIT kart project so no current would flow directly into the battery. http://web.mit.edu/first/kart/everpres.pdf I don't see a problem even if it did because a fully charged battery would be a very low resistance to any series current. We use series connected banks all the time to deliver 1000s of amps at higher voltages than one cell can deliver.
 

Thread Starter

michaeljayclark

Joined Mar 13, 2011
16
My friend is an MIT alumni and goes to MIT often. In St. Petersburg we have EVnetics.com the creater of the soliton controller that has swept the market. Ill be using the soliton junior in my EV project.

he saw the cart and talked to the lead professor. the professor liked the idea of ultracapacitors but was waiting for a battery that had the same ESR as the caps. I'd like that too but the way the cap tech is going, they will get more and more energy in these monsters and they can act like batteries. Of course EEStor claims they have the process to make that happen but I still dont see it anytime soon.

The hybrid capacitor battery is the way most companies are going. Deka is the leader in my opinion and I cant wait till they make their capacitor battery hybrid available. I have been talking with DEKA and they may sponsor our vehicles to test the battery.

I love lithium but I hate the lithium price. Lithium has on paper a almost 10 year lifespan butr that hasnt been set in stone yet. Vehicles beat up lithium pretty bad and peukerts effect is present. Their have been tests by MIT for fast charging A123 batteries and tests have shown that fast charging (Level III 400 amp charging) will kill these batteries very quickly. Headway lithium cells are the favorite of manzanita micro, a charger manufacturer. They have told me they like those better than the A123s and center their testing around headway cells. GM and Nissan both say that if fast charging is used on the lithium batteries in their EVs then tyhe warranty may not be honored even though the Nissan Leaf is fast charging ready. Time will tell..

This all has a tie in for ucaps. I think ucaps can really help lead acid AND liithium. Thats where I stand.

As far as a dc to dc converter to control the flow of energy from the battery to the ucaps I would like to go this route. Only problem is such a converter is not available. A converter to convert from 156vdc to 156vdc has to be custom made and be very expensive. Id like to do the R&D on it and make it available but of course the budget for building this EV has been reached and surpassed. Originally the project was simply batteries but after researching the ucaps I added them in and there went the budget!
 

Thread Starter

michaeljayclark

Joined Mar 13, 2011
16
A motor controller is like a dc to dc convert. It takes energy from a battery pack and controls it going to a motor. Couldnt that be adapted in this application?

I found some cheap china controllers rated at 100 amps and 40 vdc. My question is can 4 of these controllers be placed in parallel giving 160 vdc at 100 amps? that is what I am trying to do basically. As far as the controllers handling the power I am guessing that the transfer of power would only be for a few seconds if that. The ratings are top end and no way could these cheap little PWM controllers handle the current full time. they can be voltage controlled. they can be set to detect the voltage in the ucaps. turn on and ramp up sending the 160 vdc when the voltage drops below 160 vdc. When the caps are full the overvoltage circuit can tell the controllers that the caps a full and then the controllers can stop sending current.

essentially sending 100 amps of 160 volts to the ucaps in a controller manner. also would be PWM controllers.
 

shortbus

Joined Sep 30, 2009
10,045
Having read the links you gave you maybe missing the one thing they all have in common. They are all talking about using the capacitors for storing/reusing the energy of/from regenerative braking, not from being charged solely by the batteries.

Without regenerative braking the addition of the cap bank(s) is just a addition of weight and mass. Something to be avoided at all costs to make the range and life of the batteries last.

Have you seen these? http://tu-dresden.de/die_tu_dresden.../Art_Mierlo_Models_of_Energy_Sources_2003.pdf

http://hub.hku.hk/bitstream/10722/44818/1/121886.pdf

http://www.ultracapacitors.org/index.php?option=com_fireboard&Itemid=99&catid=15&func=view&id=1253

I maybe wrong and someone will tell me I am, but if you do some more searching you'll find out that the battery/ultracapacitor combination packs being experimented with are to be used on EV's with regen braking not just to lower the "P" effect.

And did you read the last paragraph in post #165 of the DIY Electric Car Forums link you posted?
 

steveb

Joined Jul 3, 2008
2,436
I maybe wrong and someone will tell me I am,
I have been telling you that you are wrong about using the label "overunity", but you don't accept it. I'm not really sure why you don't follow the OPs comments about not trying to obtain overunity, but instead looking for possible efficiency improvements.

You do bring up a valid and good point about the regenerative breaking, but that does not mean that there are not potential benefits of combining capacitors and batteries when there is no other energy source to capture. Capacitors are a no-brainer when you have regenerative breaking because of the very high peak power charging/discharging requirements there. The possible benefits of capacitors are not as easy to see in other cases, but some applications can see a net benefit in terms of greater system efficiency, better reliability and longer useful system life. There is even possible long term cost benefit, despite the capacitor cost, since the capacitors have million cycle life and the batteries may need replacement much less often when capacitors are used to aid in load leveling.

Sometimes to see a point you need to look at an extreme case. So, consider a case where the battery is loaded too much on startup, and is unable to get the vehicle moving. This could happen in cold weather, or with a partially drained battery or with an older battery. What is the efficiency in this case? Looks like zero to me because you do no work and you drain the battery down to nothing if you keep applying the load. Now, simply add some super capacitors in parallel and what happens? The vehicle is able to start moving and you have efficiency greater than zero. There is a simple example of the use of capacitors and batteries being combined to increase efficiency. No overunity is involved here.

Real cases are not this exteme usually, but they involve the same effects. An application may have peak power loading requirements (perhaps a duty cycle of 10% or even only 1%) that cause the battery to fail to perform when it is only half drained. Using capacitors can recover the other half of the battery energy by relieving the peak power load and making it look like a lower current steady state load. The goal is simply to use the available energy to do mechanical work rather than heat up the local environment.
 

shortbus

Joined Sep 30, 2009
10,045
I have stopped saying over-unity and have like you said concentrated on what the O/P posted in his links. But even that isn't good enough for you!!! And if you read the responses that others posted in this thread they basically said the same things I did without using the 'O' word.

Quote steveb "I have been telling you that you are wrong about using the label "over-unity", but you don't accept it. I'm not really sure why you don't follow the OPs comments about not trying to obtain overunity, but instead looking for possible efficiency improvements" You have been here long enough to have seen many threads start out by saying 'this is not perpetual motion' or 'this is not over-unity' and then have them closed by the moderators.

Not one place in the several (8) pages of Google links to 'ultracapacitors and EV' not one stated that the were being used with any success. Other than as a storage device for regen braking energy. Even the links by the o/p say this. The first link he posted to Diy electric cars even ended up saying they don't work/aren't worth the effort and cost. As does this thread; http://www.diyelectriccar.com/forums/showthread.php/ultracapacitors-supercapacitors-44567.html And most, if not all of the responders there have at least one home built EV on the road(Some more than one)

Maxwell and other capacitor companies are spending multi-millions on developing systems to do this and can't/haven't come up with a working system(yet) to do anything other than store regen-braking energy. They have engineers and the ability to make any size or type of capacitor they can think of and any type of auxiliary support equipment and can't make it work.

But a guy in his garage is going to make it happen? Using off the shelf caps made for electronics use? Don't think so but as you've pointed out I've been wrong before. Before this gets too far out of hand lets just agree to disagree on this subject. OK ?
 

steveb

Joined Jul 3, 2008
2,436
I have stopped saying over-unity and have like you said concentrated on what the O/P posted in his links. But even that isn't good enough for you!!! ...
Yes, it is good enough for me that you stopped saying it. I'll give up trying to convince you to stop thinking it.

Before this gets too far out of hand lets just agree to disagree on this subject. OK ?
Sure, no problem on that.
 

Thread Starter

michaeljayclark

Joined Mar 13, 2011
16
Ive met EVers that have capacitors and see the benefits. Ive seen caps in a prius that help by keeping the batteries cooler. This is a case of yes on paper the math doesnt add up, but we all know real life can be much different. a bumblebee cant fly according to the laws physics, a humming bird cant hover, and my favorite is memory chips are supposed to work the same in all computers but certain motherboards only like certain memory. I have seen situations in building computers that are not supposed to happen but they do.

I probably didnt mention it before, but I have a generator that will be charging the caps when I am in series hybrid mode. there is the source of power other than regen. To add regen, all I need to do is buy a $100 generator, take off the gas engine, put the motor on a belt running off the tail shaft of the traction motor and have an electric clutch that clutches when i hit the brakes.

I can tell you anyone I know does not have ultracapacitors in their EV yet. The ucaps only recently have some down the secondary market and are somewhat affordable.

this thread has followed the same path all the others have. ucaps are too expensive, they dont work dont try it, its a waste of time, etc etc... If Tesla worked by asking online forums first we probably wouldnt have AC power. Wed be on DC by edison, which i like better anyway when solar panels are brought into the picture.

Lets change the goal here. I am trying to gain 1% better efficiency. I love spending a million dollars for something that saves me $1. I want ucaps in my EV no matter the cost.

NOW, can we get back to my questions?

Can a simple motor controller control current from batteries to ucaps?
 

steveb

Joined Jul 3, 2008
2,436
This is a case of yes on paper the math doesnt add up, but we all know real life can be much different.
I disagree with you on that. The answer of whether it adds up on paper depends on the exact conditions and how well you are able to calculate or model the situation. Personally, I've done numerical modeling of battery and capacitors used in systems which do not have regenerative breaking or other energy inputs. In some cases, when all design constraints are factored in, the battery capacitor hybrid has significant advantages. These are demonstrated, with modeling and experimentally, or even on paper if you do it correctly.

I can't tell you what should be done in your case because I havent put the time into looking at the details yet, but it seems clear that a capacitor in parallel with the battery should aid in starting the vehicle, and would reduce stress on the battery and extend its life. Whether other topologies can do better is the real question.
 
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Thread Starter

michaeljayclark

Joined Mar 13, 2011
16
I should have added that the conditions have to match exactly and that is where the differences between calculation on paper and real world experimentation.

Kansas university did a 1997 Jimmy electric conversion. They showed the calculations on range that they did did come pretty close to what was on paper.

I attached a simply battery and ultracapacitor circuit diagram that I am going to use if correct.
 

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