Have a geeky question here and if someone does electronics they may be able to help.

[tRidiot]

I have replaced mine with high end AGM batteries, and I have a 5F cap in the truck, too. High amp alts, strong AGM batteries have solved most of my problems. My Z used to drain my battery if I didn't start it and drive it at least once a week... now it goes about 3 weeks and I keep a NOCO trickle charger on it most of the time that can properly maintain an AGM. I used an Odyssey in the Tahoe and a Northstar in the Z. Awesome batts.

*Actually, the Tahoe has an Odyssey to run the stereo and a regular lead acid battery to run the truck. They're on totally independent charging systems. You can do that with triple alternators, it's handy.

 

[MacFromOK]

Ok so 400 maybe?

Stop and think a minute. You need something that can survive being connected to the positive post and to the frame briefly (drained caps are like a dead short).

 

[eaglerjs]

pm sent

 

[MacFromOK]

Actually the best way to handle this would probably be to use a charge pump to charge the caps (again, similar to a camera flash circuit).

Might take a few seconds to charge the caps, but the battery should be safe if you disconnect it from the caps during starting.

 

[TerryMiller]

Pardon me if things have improved in the last 20 years or so, but isn't just about any electronic device subject to failure the first time it is put under load? If that still holds true, can capacitors actually last up to 5 years or so in real life?

 

[NightShade]

Actually the best way to handle this would probably be to use a charge pump to charge the caps (again, similar to a camera flash circuit).

Might take a few seconds to charge the caps, but the battery should be safe if you disconnect it from the caps during starting.

So basically have the cap bank hooked only to the starter with a monetary switch to charge them up and then release and crank it over when you are ready type of thing. Have to figure out how to setup the circuit but that could be interesting. Also work as a pretty decent start prevention circuit.

Pardon me if things have improved in the last 20 years or so, but isn't just about any electronic device subject to failure the first time it is put under load? If that still holds true, can capacitors actually last up to 5 years or so in real life?

The capacitors in question are pretty large, the main issue would be overchagring them but with them setup correctly and balance boards that is pretty much prevented. Even without balance boards in place the bank of 6 can handle a little over 16v. Since most vehicles charge at 13.8v to 14v there should be minimal risk at voltage being too high. I should also mention that ever electronic item in your home, car, rv etc has capacitors in them. Can they go bad sure. But under most conditions they will last well over ten to 15 years unless they were substandard to begin with.

 

[MacFromOK]

So basically have the cap bank hooked only to the starter with a monetary switch to charge them up and then release and crank it over when you are ready type of thing. Have to figure out how to setup the circuit but that could be interesting. Also work as a pretty decent start prevention circuit.

That would work, but I'd probably just disconnect the battery when starting and when the ignition is off. That way, simply turning the ignition switch on would charge the caps, then hitting start would disconnect the battery.

Also a few (or even several) volts over 12V shouldn't hurt the starter motor. Just don't exceed the cap voltage rating.

 

[NightShade]

That would work, but I'd probably just disconnect the battery when starting and when the ignition is off. That way, simply turning the ignition switch on would charge the caps, then hitting start would disconnect the battery.

Also a few (or even several) volts over 12V shouldn't hurt the starter motor. Just don't exceed the cap voltage rating.

Right well what I am kinda thinking is the only times the caps would be charged is when I am ready to start. I have a single lead that runs to the starter and another one that supplies the power to the vehicle and everything else. Setting up something to charge the caps would be pretty simple as long as I can keep the draw down. And if I am going to listen to the radio or something I could charge the caps so they are ready to go when I want to start it.

But for right now everything is in the theory phase.

 

[Oklahomabassin]

Are you thinking the deep cycle battery will last significantly longer than a regular battery?

 

[NightShade]

Are you thinking the deep cycle battery will last significantly longer than a regular battery?

Of a decent design, yes.

https://www.solar-electric.com/learning-center/deep-cycle-battery-faq.html/

But even a regular battery that isn't put under heavy loading will last longer. A deep cycle can also be desulfated a few more times where a starting battery will have issues using epsom salts. Deep cycle batteries have a little more distance between plates and a larger tray in the bottom to hold the stuff you are able to slough off.


He may be a little harsh to your ears but the info is very good.

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