Hacked Gadgets Forum

November 13, 2013

Car Started with Capacitors?

at 12:30 am. Filed under Crazy Hacks


What do you guys think? Is this real or bogus. It would be very simple to fake since you could simply tie in a regular battery somewhere in circuit but with new capacitor technology I am thinking this could be real? The caps that are being used are 350F!! That is crazy but the total amount of energy available is not as much as a regular lead acid battery you would find in your car but with a small 4 cylinder  vehicle it might be an interesting solution.



Viagra drug to impotence dysfunction, side drug interactions viagra . Viagra drug to impotence dysfunction, side drug interactions...

Related Posts

Bypass Capacitor Tutorial
1600 Volt Can Crusher
Digital Capacitors
Power Supply Decoupling and Filtering
Samsung Syncmaster 204B Monitor Repair
How to Replace a Capacitor
The Useless Candle
LED Fireworks



17 Responses to “Car Started with Capacitors?”

  1. Flyer Says:

    Yeah that will totally work. The bosst pack has lower energy than a battery, however that doesn’t matter to start a car, what yoy need is current, and a lot of it. Usually to start a car you will need around 50 amps (since the electric motor that turns the engine is in short circuit when it has the maximum torque, while the combustion engine in stoped has zero torque). These supercaps can provide more than 100 amps during a short period of time, what matter in these supper capacitors is the internal resistance (that limits the maximum amount of current that they can provide)

  2. Jamie Says:

    Definitely real. The total energy stored in 6x 350F caps is much less than a regular lead acid battery, but the energy required to start a car is only a fraction of that. The caps will recharge very quickly once the car is started, so the only real downside is that if you left the lights on while the car was off the caps would be ‘dead’ faster than a battery would. On the upside of that, they’d survive many more cycles of going full dead than a normal car battery would and you could probably recharge them with a modest solar panel in 20 to 30 minutes.

    I don’t know much about how the electronics in cars are wired up, but if I was going to do this I’d look into a simple circuit to cut the power when the capacitors were providing less voltage than a battery would to avoid under-voltage failures.

  3. Steve Says:

    I’ve used my quadcopter battery to jump start my car hundreds of times now! https://www.youtube.com/watch?v=MLVvnsT07nk

  4. Kev Says:

    You don’t get 2100F, you get only about 58.333..3F because the rule for capacitors in series is 1/(1/C1+1/C2+…+1/Cn). Assuming they’re all charged at 2.7V (cf datasheet), that’s a total of 7654.5 joules, or 2.1263 watt hours or 131.25 mAh

  5. Kev Says:

    You might actually be able to start a car with a 6400mAh 3S lipo battery though, one rated 40C (with 80C burst) is able to output its full capacity at 256A and burst up to 512A.

  6. Nick Says:

    For 6 capacitors in series (350F @ 2.7V), that’s around 16v and 58F capacity:

    1/((1/350)+(1/350)+(1/350)+(1/350)+(1/350)+(1/350)) or

    1/((1/350)*6) = 58.3F

    Assuming a starter motor draws 100A (but can be much higher), that would give you around 2.7 seconds of juice.

    I used this page: http://www.circuits.dk/calculator_capacitor_discharge.htm to get that figure, assuming Vcapmax=13V, Vcapmin=8V, 58F, iMax=100,000,000uA, Cap ESR=0.0032Ohms (for this cap anyhow).

    I’ve guessed at some of those figures though, Vcapmin maybe too low to still operate a starter motor, the Vcapmax could be higher (alternators vary from 13.3v to 14.7v according to a page found on google), and the discharge would be offset by any remaining power in the battery.

  7. Dougal Campbell Says:

    It’s been too long since I studied the qualities of capacitors in college physics lab. My only quick calculation is that they probably have about 1/5 the capacity of a regular car battery, does that sound right? So cranking a car seems feasible, and Jamie’s notes above look reasonable to me.

  8. Scott Says:

    With a ESR of 0.0032 Ohms that will deliver a large amount of current but just for a few seconds. If the car is in good shape and starts on the 1st try I have no doubt it will start it. Most cars only take 200-500 amps on crank that looked like a 4 cylinder so i am sure its less more like 150 amps. But if that car didn’t start on the 1st crank i am sure there wont be a 2nd try.

  9. Tony Says:

    Bollocks for a few reasons.

    6x350uF sounds a lot, but since the caps are only ~2v, it’s really one 12v 350uF capacitor.

    First up, energy density. For their size, lead acid battery holds 10 times the energy of super caps. To hold the same power, you need a lead acid battery 1/10th the size of the caps shown, about the size of a ‘C’ cell battery. Think that’ll start your car…?
    I have a drill powered by supercaps. It charges very fast, but only has a couple of minutes of run time. That’s maybe two of the cells. They can barely run a drill, let alone crank a car.
    Discharge curve. The discharge curve of a car battery is pretty flat, a charged battery is about 12.6v, a ‘flat’ one is anything under 12v. His caps were 10v… Caps lose voltage very quickly, you need a boost circuit to keep the voltage about 12v.
    Caps would work, but you need a lot more than he has. And no, the ‘hybrid’ pack won’t help much.

  10. Tommy Says:

    First: get that extra “u” out your head. Those are 350 Farad caps, not 350 microFarad caps.
    The total capacitance is (simplified since they have the same value (350 F)/(6 caps)= 58 Farads.

    Second: you’re comparison of energy/power density is a bit confusing.
    The ENERGY density of the classic acid battery is a lot higher than that of the supercapacitor(s) bit the POWER density of the battery is a lot lower than that of the super caps.
    To start the engine (and thereby the alternator) you only need a short but powerful burst, so the supercapacitors are just right for that job.
    As long as you can get the engine/alternator to turn a few cycles then the alternator would generate enough voltage/potential difference to keep the supercapacitor happy and thereby eliminating the need for the large energy reserves of the lead acid battery.

  11. Roger Says:

    F not uF.

  12. Derp Says:

    Very real, but should be done differently. For starters the voltage comming out of the alternator is higher then the full voltage of the lipo pack, also there appears to be no ballance circutry which was the likely demise of the battery, running lifepo4 instead would solve that and still have the same benefits of using the insane discharge currents availabe from the super caps, there are alread lipo packs capable of starting cars alone.

  13. hoser Says:

    Tony. Just remember that in series these caps could charge up to 16.2 volts but that series wiring them would end up reducing their total capacitance to 1/6 the value. Or 58.3 Farads. With this amount of current and voltage this would be enough to turn a car starter for several seconds. Two C batteries in series could effectively recharge these caps in a matter of minutes so the answer to your statement about starting a car with C batteries is “Yes, if you use a couple of them to charge a 58.3 Farad ultracapictor stack running at 16.2 volts!”. Remember. Small batteries have the energy to do that work…but cant put it out in the time necessary to be effective. Which is what the ultracaps do. So….this is a time-varied capacitive starting system. All you need to do to test this is charge the caps in parallel with the C battery stack. Yes it will take a while to charge them up from O volts. But once charged they will only dip a few volts which means they will recover quickly. Especially if the charging system is recharging the caps!

  14. Tony Says:

    Yeah, brain fade on the caps in series – which actually makes things worse.
    @Tommy, the alternator won’t be producing any power at the revs the starter is running at, IF there is enough energy in the caps you get exactly one shot at starting your car. That’s why batteries are the size they are.

  15. hoser Says:

    So. Lets review. We can’t use an ultracap setup more than once to start the car. But if we make a hybrid battery with smaller batteries doing a slow recharge we could make something that would have one good start from the D cell sized caps. But, you could also use the monster 3000 F caps in series like the guy did before he went to the D cell ultracaps. That would give you 9X the cranking time AND you could still have a small standby battery for keeping the cars clock and computer settings in place. Or maybe a few nicds placed around the car for that would be a good idea? Hey….how about a hand crank generator somewhere in the car? Your caps are flat? No problem! Just crank this handle for five minutes and you will have a good push to start the car! No more dead batteries ever!

  16. Alexander Says:

    Who else was waiting for him to touch the metal frame on the scale with those two live contacts for the fireworks? 😛

  17. PAm Says:

    Funny how he just ignored every advice about balancing and properly charging that LiPo battery pack. Not to mention under voltage cutoff so the batteries don’t get destroyed. I think it is real, this guy just has no idea what he is doing/talking about. Properly using those ultra capacitors they should also have at the very least some crude over voltage suppression circuitry. Car alternator and electical system doesn’t equal clean and nice voltages.

Internal Links:



Hacked Gadgets

Site Sponsors:

Nuts and Volts Electronic Labs Trossen Robotics Free Technical Publications Blue LED


Recent Comments:

More RSS Feed Options

Site Sponsors:


Interesting Sites: