Capacitor bank on vehicle battery

[cheapie]

Re: Capacitor bank on vehicle battery

If I understand what you're trying to do, you're trying to connect some caps in series to get something that can handle 15V or so, and wire that in parallel with the battery, so that it's charged slowly by the battery and provides a quick burst of current to start the engine? If so, the caps should help.

[domas]

Re: Capacitor bank on vehicle battery

no, he was about to hook up some different rated caps in parallel to the battery, of course all of them should be 16v++ rating, post #10

[senz_90]

Re: Capacitor bank on vehicle battery

If I understand what you're trying to do, you're trying to connect some caps in series to get something that can handle 15V or so, and wire that in parallel with the battery, so that it's charged slowly by the battery and provides a quick burst of current to start the engine? If so, the caps should help.

Im sorry to makes misunderstand here because the picture not too clearly (just realized Im wrong to say it as a series caps circuit to be connected parallel with battery ) I want try to make different rated caps connected parallel with battery as a current booster if this could prolong battery life and help to starter easily. I think to use 16V caps like domas said

This schema maybe makes it clear.

no, he was about to hook up some different rated caps in parallel to the battery, of course all of them should be 16v++ rating, post #10

I have think to use 16V rating since it was more than enough. when first see the site I have question for different rated of caps function. after read it, some different rated caps hook is to smooth different ripple from battery as the site said.

[domas]

Re: Capacitor bank on vehicle battery

I understrand the idea of "current booster", but i still do not get what do you mean by battery ripple. Battery is giving the most DC output ever imagined

[senz_90]

Re: Capacitor bank on vehicle battery

I understrand the idea of "current booster", but i still do not get what do you mean by battery ripple. Battery is giving the most DC output ever imagined

I have said that the site have said it, not me. So I have same question like you. LOL. I think the battery is give pure DC without too much ripple or maybe none (im not expert on battery knowledge). Maybe he/she means to save electronic components on vehicle and describe it on wrong way. He/she on the thread has test the circuit on linear and switch psu, motorbike, and car battery with laptop oscilloscope. it gives a good smooth ripple from the picture.

this is the site, please translate it with googletranslate or chrome if you don't understand

http://www.saft7.com/bikin-voltage-s...uk-mobilmotor/

[tom66]

Re: Capacitor bank on vehicle battery

I doubt those caps will do anything significant -- if you want a substantial effect you need to use capacitors on the order of hundreds of farads.

Most of the ripple on the battery voltage will come from the ignition system in the car, if it is a newer model using electronic ignition, not even this will have much effect because a switch mode converter is used (IIRC.)

The alternator rotates at the engine RPM and will produce ripple on the order of the number of poles * RPM, typically 4 to 12 poles in a DC generator so you might be looking at 70Hz ripple for a 700RPM idle, 6 pole vehicle.

Things like the radio, fans, ecu, cooling systems, etc could have effects.

All of these components and the battery are designed to withstand this and typically this doesn't pose much of a problem. Ripple on a battery won't cause significant harm unless the ripple is extreme.

[selldoor]

Re: Capacitor bank on vehicle battery

Looks to me like the item referred to in the article is not a current booster as such, but a gadget which might or might not smooth out or add additional regulation (while the car is running )when the battery is switching between charged/discharged. So maybe useful to reduce "noise" on a car audio. IF it works at all I guess you could class it as fine tuning but I doubt if it will make any material difference to charging your battery or enabling better starting.
Maybe your alternator needs some adjustment? If you have a continuing problem
perhaps ask on a dedicated car electronics site.
The reviews of the products on the three reference sites seems very vague.

[senz_90]

Re: Capacitor bank on vehicle battery

I doubt those caps will do anything significant -- if you want a substantial effect you need to use capacitors on the order of hundreds of farads.

From the site picture I guess not a much different and this is makes me ask this great forum member. So after this statement I think this is not a better solution. As you said hundreds of farads, I have to make a bunch bunch bunch caps to get it to hundred Farad (not micro, nano, or pico). It seems like I have to consider again to make this.

Looks to me like the item referred to in the article is not a current booster as such, but a gadget which might or might not smooth out or add additional regulation (while the car is running )when the battery is switching between charged/discharged. So maybe useful to reduce "noise" on a car audio. IF it works at all I guess you could class it as fine tuning but I doubt if it will make any material difference to charging your battery or enabling better starting.
Maybe your alternator needs some adjustment? If you have a continuing problem
perhaps ask on a dedicated car electronics site.
The reviews of the products on the three reference sites seems very vague.

hmm. you think this is not make much different for starting too?
I think tomorrow i have a time to try this, but you two makes me afraid and this is waste of money and time. lol. thank you for your thought.

[Logistics]

Re: Capacitor bank on vehicle battery

Batteries have a harder time when it's cold out, but most of the time you just need to clean your connections: the battery posts, connectors, any spade-connectors or bolt-on eyelets in the system, etc. And if its a traditional battery, keep it filled up with distilled water.

All basic stuff; you aren't trying to start some high-compression performance engine, it should be an easy fix unless the battery really needs replacing.

[domas]

Re: Capacitor bank on vehicle battery

Batteries have a harder time when it's cold out, but most of the time you just need to clean your connections: the battery posts, connectors, any spade-connectors or bolt-on eyelets in the system, etc. And if its a traditional battery, keep it filled up with distilled water.

All basic stuff; you aren't trying to start some high-compression performance engine, it should be an easy fix unless the battery really needs replacing.

apparently that i have fixed some non-starting cars with this basic stuff;

regarding capacitor bank, it would be easy to test it. and i wouldn't care about ripple in the cars for some reason. But to make starting easier in freezing temps - why not?

Well if a typical older diesel engine requires about 200A of current for lets say 1-2 seconds, depending on the condition of engine, you do the math. If you crank your engine for 1.5 seconds for let say 200->>100a of current (which will decrease when the RPM's will increase), so lets assume that average current is 150A

therefore
12V * 150A * 1.5 = 2700J of energy will be used provided that capacitor is supplying the whole energy demand
Calculating farads
(2*E)/(V^2) = C
therefore it is 37.5Farads at 12V (2*2700J / 12*12)

If it is a petrol engine your best guess is 100A. If it is a motorcycle engine it is way less

IIRC my 5 cyl 9,3:1 compression Audi has a 1,4kW starter motor.. So it is 120A max... but it is max, i doubt that is uses more than 50-70amps normally

Then again, find a capcitor bank that is able to supply 200 amps of current - try connecting 4 10F caps in parallel making sure each one is able to supply 50A of current for my mentioned application

It will most likely end up in smoke, but you can't know before you try

[ben7]

Re: Capacitor bank on vehicle battery

I doubt those caps will do anything significant -- if you want a substantial effect you need to use capacitors on the order of hundreds of farads.

I second that. There is no need for a ton of 4.7uF caps either. Just a few big can-style caps.

All of these components and the battery are designed to withstand this and typically this doesn't pose much of a problem. Ripple on a battery won't cause significant harm unless the ripple is extreme.

And... I'm not sure how much ripple there would be, but you'd have to be sure that it won't be over-stressing the caps.

And, if you were to use can-style caps, they are almost all rated at 85C... not good enough for an engine compartment in my opinion.

[budm]

Re: Capacitor bank on vehicle battery

Car alternator is 3-phase variable frequency system for low ripple.

[senz_90]

Re: Capacitor bank on vehicle battery

It seems like I have to read some knowledge more about battery and engine.

I didn't sure enough I am understand from domas calculate and said. "4*10F can caps would do but it will most likely end up in smoke". something that afraid me. I have try asking my local store about can caps since I haven't experience before so I am not buy it yet. would can caps better than the circuit I am upload? So i have to makes 40 Farad caps from big can caps to make this as current booster?
200A is for starter engine?

Ben7, I dont want to use 85C caps too, it would likely die than before my battery. So you think a few big can caps will suite?
Logistics, I have try clean all connections with warm water and oil it with WD40 to prevent oxidizes, but it seems like my battery near his end of life and I have to buy new one. I just confuse what is the better use for caps? can caps or common radial caps?

I have search site published from my country person to sell this caps bank. They make this caps around 100000 uF for car (common), maybe there is little than this, someone makes it more uF (more expensive too). I am never see they make this on Farad value, so what is the better?

[domas]

Re: Capacitor bank on vehicle battery

1. Well my thoughts are theoretical as well. So take it with a grain of salt as I have no experience with that.

2. Well, the ending up in smoke thing is more as a precaution for you to make sure that you use cables, caps, and connectors that are capable of transferring the current. What some of us were trying to say is that we did not agree with the idea of using different small caps, we would rather use few big ones (as the idea we agree with is to use it as current booster) instead of using it to smoothen the ripple. And yes whatever the configuration is, make sure they can transfer enough current.

3. as we all know lead-acid batteries have limited service life. And at some point you just have to get a new one or a better used one if that is what you prefer. But you can still try desulphating it or using epsom salt - this will give extra lifetime, but it will not magically fix it.

4. 100000 uF (100F) caps, is it a single unit or a capacitor bank? if it is 12/16V i guess it is pretty big.

5 Regarding 200Amp starter motor yes it is comon for diesel engines. Mine is 1.8kW, so you do the math: 1800/12 = 150A but it is a small engine. But again don't expect the motor to work on that load constantly... that is the very starting point at very worst conditions.. Why do you thing an average car battery is something like 540A en (capability of starting current) with 75Ah of capacity @ 12V
Thats an example of my diesel starter: http://www.iauto.lt/vag/VW/Golf_81/G...s_ID=100068496 as you can see it is under position (1) and it is 1.8kW

...and a petrol one: http://www.niparts.com/Graphics/full...%5C1739536.jpg

But please post some details of the application you want to use it for. Engine, size, compression, fuel, vehicle type, what battery do you have now, and so on.

Will be happy to help

[senz_90]

Re: Capacitor bank on vehicle battery

1. Well my thoughts are theoretical as well. So take it with a grain of salt as I have no experience with that.

2. Well, the ending up in smoke thing is more as a precaution for you to make sure that you use cables, caps, and connectors that are capable of transferring the current. What some of us were trying to say is that we did not agree with the idea of using different small caps, we would rather use few big ones (as the idea we agree with is to use it as current booster) instead of using it to smoothen the ripple. And yes whatever the configuration is, make sure they can transfer enough current.

3. as we all know lead-acid batteries have limited service life. And at some point you just have to get a new one or a better used one if that is what you prefer. But you can still try desulphating it or using epsom salt - this will give extra lifetime, but it will not magically fix it.

4. 100000 uF (100F) caps, is it a single unit or a capacitor bank? if it is 12/16V i guess it is pretty big.

5 Regarding 200Amp starter motor yes it is comon for diesel engines. Mine is 1.8kW, so you do the math: 1800/12 = 150A but it is a small engine. But again don't expect the motor to work on that load constantly... that is the very starting point at very worst conditions.. Why do you thing an average car battery is something like 540A en (capability of starting current) with 75Ah of capacity @ 12V
Thats an example of my diesel starter: http://www.iauto.lt/vag/VW/Golf_81/G...s_ID=100068496 as you can see it is under position (1) and it is 1.8kW

...and a petrol one: http://www.niparts.com/Graphics/full...%5C1739536.jpg

But please post some details of the application you want to use it for. Engine, size, compression, fuel, vehicle type, what battery do you have now, and so on.

Will be happy to help

As I said friend, that 100000 uF (100F)caps is a capacitor bank (maybe made from different radial lead uF caps), not just a few of big can caps from Farad value. Yes, I'm agree with you to makes this as current booster, smoothing the ripple is just bonus.

correct me if I am wrong, didn't uF is 10-6 so 100000uF = 0.1F? I am really beginner on vehicle engine so I don't know what details to post. I don't know the power of my engine like yours is 1.8kW, my battery maybe is not as big as you think.

the battery label detail is 12V capacity 3.5Ah / 10Hr, engine size on 110cc, my engine is use petrol. this is motorbike. I think to try this capacitor bank first on motorbike since I don't hope my battery will be fixed I will buy a new battery and try this capacitor bank. So the connector I have using must be capable for the current flow, I am understand.

[domas]

Re: Capacitor bank on vehicle battery

OOOOOOK, now i see what are we talking about.

And yes, i have made a mistake with calculating Farads. My bad

So if it is a motorcycle engine so it is way less amps/watts/farads, you have to find it out yourself :-) That makes things much easier.

The battery you are talking about is a small one, but is probably enough for your application. Is it your daily vehicle? Short, long distances between starts? It would also be interesting to see how would it work with a capacitor only, no battery

Are you trying to prevent a problem or you already have a problem starting it?

Is your battery sealed lead acid or do you have access ports to acid inside?

[senz_90]

Re: Capacitor bank on vehicle battery

OOOOOOK, now i see what are we talking about.

And yes, i have made a mistake with calculating Farads. My bad

that's normal friend

So if it is a motorcycle engine so it is way less amps/watts/farads, you have to find it out yourself :-) That makes things much easier.

How to find it? maybe dumb question but what parameter that I should look?

The battery you are talking about is a small one, but is probably enough for your application. Is it your daily vehicle? Short, long distances between starts? It would also be interesting to see how would it work with a capacitor only, no battery

Yes, the battery is small one and my daily vehicle. I don't think that would work if just a 100000uF exhange with battery.

Are you trying to prevent a problem or you already have a problem starting it?
Is your battery sealed lead acid or do you have access ports to acid inside?

I have problem already from this battery which hard to start. it needs 4-5 times to push starter button before start. So I think to buy a new battery and makes this capacitor bank to prevent further problem like this, to prolong it and as current booster to makes it easier start (somebody mention capacitor bank could be), but the question is what values or what circuit is the best for my application?

it has access ports to acid inside, so we should fill the battery liquid periodically to makes it longer life.

[tom66]

Re: Capacitor bank on vehicle battery

You can replace a car battery with a super capacitor bank http://www.youtube.com/watch?v=z3x_kYq3mHM

[ben7]

Re: Capacitor bank on vehicle battery

You can replace a car battery with a super capacitor bank http://www.youtube.com/watch?v=z3x_kYq3mHM

LOL the chickens in the background, I them to be funny creatures :P

11 bucks on digikey?! I'm almost tempted to get a few of them myself! :O

I still worry about the lifetime of them. Maybe better to put them under the car, so theoretically they would stay a bit cooler.

[domas]

Re: Capacitor bank on vehicle battery

that's normal friend


How to find it? maybe dumb question but what parameter that I should look?



Yes, the battery is small one and my daily vehicle. I don't think that would work if just a 100000uF exhange with battery.


I have problem already from this battery which hard to start. it needs 4-5 times to push starter button before start. So I think to buy a new battery and makes this capacitor bank to prevent further problem like this, to prolong it and as current booster to makes it easier start (somebody mention capacitor bank could be), but the question is what values or what circuit is the best for my application?

it has access ports to acid inside, so we should fill the battery liquid periodically to makes it longer life.

Just do the math like i did, calculate the needed energy for starting the engine, measure the current or something. Check the starter motor, or at least its fuse if it has one, to find out how powerful it is. Or please state the model of your motorcycle, somebody will be able to find it in the internets.

Just an idea: it sounds that there is some problem with fuel/air mixture, timing, carb/injection system, compression.. I mean, if it takes long time to start the motorcycle, 4-6 starter cycles is a lot, then it might be that the battery is not a core problem, it is more a victim of a problem.

How does it start if you charge you battery with mains charger and try to start it just instantly after that?