Super Capacitor Jump Starter

[GlenBaker]

Does anyone have experience with a
Super Capacitor Jump Starting units?
Such as the autowit supercap 2 unit
https://www.autowit.com/products/autowit-supercap-2-jump-starter
I have had good luck with my small Diehard lithium ion jump starting battery as long as I remember to keep it charged. I was thinking of buying another ion unit when I saw these super capacitor jumpers and did know how good they were.

 

[NYECOGunsmith]

I'm kinda doubting it, unless things have changed since I got a degree in electronics decades ago.
First off a capacitor can only charge up to the voltage presented to it by the battery or the power supply supplying DC voltage to it.

Second, it takes a pretty fair sized capacitor to store up a really useable amount of current.
A capacitor's storage potential, which is called it's capacitance, is measured in units called farads.

And a 1-farad capacitor can store one coulomb of charge at 1 volt DC, since capacitors block (store) DC and pass AC. . A coulomb is 6.25e18 (6.25 * 10^18, or 6.25 billion billion) electrons.
And one amp is defined as a rate of electron flow of 1 coulomb of electrons per second, so a 1-farad capacitor can hold 1 amp-second of electrons at 1 volt DC. .

Lastly a 1 full Farad capacitor is generally pretty big. Somewhere between the size of a can of soda and a 2 liter bottle of soda, depending on the type of capacitor (Mylar, Tantalum, Paper, Electrolytic, Glass, Air, Paper, etc. ) and depending on the voltage it can handle. That's why most capacitors are measured in microfarads (millionths of a farad), or Pico Farads (billionths of a Farad) .
Take a look at the start/run caps on a AC motor like on an HVAC unit for example, or a table saw, etc. They are pretty big.

I just can't see one of these so called "Super Capacitor Jump Starters" being hooked up to a dead battery (some claim to work with a 12 Volt car battery down as low as 3 volts!) , one so dead that it won't even make the starter solenoid on the car click or turn on the head lights, but somehow it will charge up this super capacitor in just 90 seconds from the "reserve capacity that all dead batteries have" as one ad put it, then delivering the 12 VDC at 200 to 400 or more amps to turn over a cold engine, especially like one ad says "Works down to as low as -40 degrees F!".

I'm probably an out dated dinosaur, and the technology has passed me by, but the physics just ain't there in my feeble mind.

When the well is dry, you can't get more water out of it, when the battery is dead, you can't get more voltage and current out of it by hooking a capacitor of any size to it.

Just my .02 worth, one of the young whippersnappers here , like that smart aleck apprentice of mine, will probably be along shortly to prove me wrong!

 

[leonandlisa]

This guy does unbiased reviews, not sure if he mentions your brand, but gives you a good overview.

 

[Fogie]

Have yet to have one work

 

[GlenBaker]

Have yet to have one work

What ones have you tried?

 

[Fogie]

What ones have you tried?

..a couple my buddy had, not sure of brand.

 

[totenschadel]

FWIW I've personally witnessed the Halo Bolt 58830 function on a few cars that batteries were DOA. Seems to do it's intended job, and the Amazon reviews seem to be really positive.

 

[Harley]

I'm kinda doubting it, unless things have changed since I got a degree in electronics decades ago.

Artists rendering of him in class giving a presentation of his finals project.

 

[Janizary]

I have several of the Li Ion flat pack batteries that have worked just peachy for several cars and a truck, but never a capacitor version.

 

[GlenBaker]

This guy does unbiased reviews, not sure if he mentions your brand, but gives you a good overview.

Thank you, he just proved that super capacitor jump starters do work. Not as good as battery packs but battery packs are ONLY GOOD IF CHARGED sometimes I forget to charge mine. In that case the super cap is better than nothing.
Thank you

 

[SixshooterSam]

The Powerall by Supreme is the best jumper pack on the market, period. At least in my experience. I've had mine for five years, and have used it EXTENSIVELY.. Not just for jumping dead cars (could not even count how many times I have), but also for powering all kinds of stuff. 12 volt air compressors, lights, charging my phone/iPad, etc etc... I am AMAZED at this little guy, especially how it continues to work so well after five years of abuse. Now I will say, it is starting to get a little tired now, but I have used the absolute hell out of it. Not many tools really amaze me any more, but this one sure does.

I wouldn't even waste my time with a capacitor based jumper. I simply can't see that working well at all in most circumstances.

https://www.thepowerall.com/product-page/supreme

 

[NYECOGunsmith]

In the test video above, it shows the Supercapacitor battery jump starter being charged up to 15.5 volts and then delivering 261 amps at a reduced voltage of 8 volts.............so, what did he charge the capacitor off of?
There is no way a battery that is down to 4, 6, or 10 volts can charge a capacitor to 15.5 volts AND accumulate 261 amps at 8 volts.
Next problem is, only batteries deliver voltage and current over a "long" period of time, a capacitor dumps all it's voltage and all it's current in one brief flash.

That's why they are used in camera flash systems where a battery charges up the cap, to a voltage higher than the battery's by use of a DC to DC oscillator circuit often called a DC booster with a chopper circuit in it. Then it dumps the voltage from the capacitor to the flash tube to produce the single brilliant strobe flash.

Since you can't feed DC into a transformer and boost the voltage or reduce it, you first have to convert the solid DC output to a intermittent one, that fools the transformer and the voltage passes through it, either being increased or decreased depending on the ratio of the windings on the primary side to those on the secondary side.

Now I suppose it would be possible to charge that super capacitor to a voltage higher than the battery's measured voltage via a DC to DC converter, but then you have the problem of voltage and current being inversely proportional, as voltage rises, current falls.

Voltage is like water pressure in a pipe, but instead of PSI (Pounds Per Square Inch) we measure it in Volts, and current in an electrical circuit is like flow in gallons per minute of water through a pipe.

Now if the bucket only has enough depth of water to create 4 PSI (Volts) via gravity, and there is only a quarter of a gallon of water in the bucket, sure, you could hook a pump to the bucket and pump it out at say, 12 PSI, but if you are putting out a fire that is large enough to require 200 to 400 GALLONS(Amps) of water, well, get out the marsh
mellows, graham crackers and Hershey bar, we'uns is gonna have SMORES.

So I just can't see that super capacitor being JUST a capacitor, even with a DC to DC converter boost circuit in the case, where does all that amperage come from?

And as for that First cordless power drill, WRONG Harley, that wasn't the first, the first was the one with the baby stegosaurus in it, in my other invention which later became known as a "Hamster Wheel".

 

[SixshooterSam]

In the test video above, it shows the Supercapacitor battery jump starter being charged up to 15.5 volts and then delivering 261 amps at a reduced voltage of 8 volts.............so, what did he charge the capacitor off of?
There is no way a battery that is down to 4, 6, or 10 volts can charge a capacitor to 15.5 volts AND accumulate 261 amps at 8 volts.
Next problem is, only batteries deliver voltage and current over a "long" period of time, a capacitor dumps all it's voltage and all it's current in one brief flash.

That's why they are used in camera flash systems where a battery charges up the cap, to a voltage higher than the battery's by use of a DC to DC oscillator circuit often called a DC booster with a chopper circuit in it. Then it dumps the voltage from the capacitor to the flash tube to produce the single brilliant strobe flash.

Since you can't feed DC into a transformer and boost the voltage or reduce it, you first have to convert the solid DC output to a intermittent one, that fools the transformer and the voltage passes through it, either being increased or decreased depending on the ratio of the windings on the primary side to those on the secondary side.

Now I suppose it would be possible to charge that super capacitor to a voltage higher than the battery's measured voltage via a DC to DC converter, but then you have the problem of voltage and current being inversely proportional, as voltage rises, current falls.

Voltage is like water pressure in a pipe, but instead of PSI (Pounds Per Square Inch) we measure it in Volts, and current in an electrical circuit is like flow in gallons per minute of water through a pipe.

Now if the bucket only has enough depth of water to create 4 PSI (Volts) via gravity, and there is only a quarter of a gallon of water in the bucket, sure, you could hook a pump to the bucket and pump it out at say, 12 PSI, but if you are putting out a fire that is large enough to require 200 to 400 GALLONS(Amps) of water, well, get out the marsh
mellows, graham crackers and Hershey bar, we'uns is gonna have SMORES.

So I just can't see that super capacitor being JUST a capacitor, even with a DC to DC converter boost circuit in the case, where does all that amperage come from?

And as for that First cordless power drill, WRONG Harley, that wasn't the first, the first was the one with the baby stegosaurus in it, in my other invention which later became known as a "Hamster Wheel".

I have to say.. I know a couple things about that newfangled electricity type stuff.. but NYECO's posts in this thread make me want to check the thickness of my cranial plates, cause I'm feeling like a neanderthal after reading them!

 

[Harley]

I have to say.. I know a couple things about that newfangled electricity type stuff.. but NYECO's posts in this thread make me want to check the thickness of my cranial plates, cause I'm feeling like a neanderthal after reading them!

Them geezers DO know a thing or two!

 

[lvjunk]

I can attest that they work, though I had my doubts. Neighbor loaned me his the other night (FIL has my jumpers - not sure why I dont have them back, guess I’m buying new ones) and it did its job immediately. I’m a converted believer.

 

[NYECOGunsmith]

Thank you, he just proved that super capacitor jump starters do work. Not as good as battery packs but battery packs are ONLY GOOD IF CHARGED sometimes I forget to charge mine. In that case the super cap is better than nothing.
Thank you

I didn't see him or hear him say what he hooked the super capacitor up to to Charge it, he just starts out with taking it out of the box, then the next thing is he has it hooked up to his ammeter and his carbon pile battery load tester, and miraculously it is showing 15.5 volts and when he puts the carbon pile load to it, 261 amps at 8 volts for several seconds.
Despite what the box on most of those super capacitor jump starters say about not having a battery inside, there pretty much has to be, as a capacitor dumps all its stored voltage and current in on big rush of a couple of milliseconds, where a battery delivers it over time, seconds or more.

A good alkaline AA battery will have a 2800 Milliamp Hour rating, which is 2.8 Amp hours, which means theoretically it will deliver 2.8 amps at 1.5 volts for an hour. To get a capacitor to store 2.8 amps it would have to be huge.
The AA battery delivers that 2.8 AH over a long period of time, one hour, but if you dead short that battery it will deliver a higher current, for a much shorter time, but it usually destroys the battery or sets things on fire.

A fresh alkaline AA battery with a voltage of 1.5 Amps and a current rating of 2.8 AH, can, in theory according to the math, deliver about 10 amps at 1.5 volts for a couple of seconds, in tests it usually runs about half that much, 4.5 to 5 amps, and the battery gets way to hot to hold.

If the AA battery voltage is 1.5 volts, then to store that 2.8 AH (4.2 Watts) of power in a capacitor would require 3,600 (the number of seconds in an amp hour) times 1.866 (2.8 divided by the voltage of 1.5) which would be 6,720 Farads of capacity.

That would be one huge capacitor no matter what the dielectric material used to make it is.

I personally use the Stanley Lithium Ion jump starters from Wal Mart, and have had great luck with them in terms of them getting the car started, holding a charge for a long time, and not dying out after just a couple of years.

 

[SixshooterSam]

I can attest that they work, though I had my doubts. Neighbor loaned me his the other night (FIL has my jumpers - not sure why I dont have them back, guess I’m buying new ones) and it did its job immediately. I’m a converted believer.

View attachment 76203

View attachment 76204

Just for clarification, that's a battery pack, not a capacitor jumper.

 

[SixshooterSam]

Thank you, he just proved that super capacitor jump starters do work. Not as good as battery packs but battery packs are ONLY GOOD IF CHARGED sometimes I forget to charge mine. In that case the super cap is better than nothing.
Thank you

While this may technically be true, in practice I find this thought process leaves many people worse off, as the "better than nothing" mentality gives you a false sense of security. If I were only going to carry one or the other, I would always choose the battery jumper pack. If you want both, carry both, and try the capacitor route first. That way you haven't wasted potentially valuable battery power if the capacitor was enough to get the job done.

I suspect in the real world, a capacitor jumper isn't going to help most people, so I would not consider it a particularly useful or valuable tool.

 

[lvjunk]

Just for clarification, that's a battery pack, not a capacitor jumper.

Lol yeah I guess I should have read more before replying. Totally just skimmed this one and provided my two cents. How liberal of me to do so. My most humble apologies.

 

[Ronsmag]

I have one but it's a big thing that has a air compressor and bluetooth speakers, ac converter, you can plug in into a wall outlet to charge it or into the power port in the car but it works good. Use it more for the air compressor, but have started cars with it. Saved two guys trying to pump up a tire with a bicycle pump in the home depot parking lot, it was 110 degrees they were happy I stopped for them