SUPERcapacitors / battery

[xwrench3]

i want to make a super-capacitor "battery"  for my ATV. but i am going to have to do some research before i do. if any one knows of a GOOD "how to" article or two on this subject, it would really help. i have found a couple of articles discussing it, but nothing relating to actually making one, or how to figure out the specifics to get the correct parts. all help would be appreciated. thanks.

[bob345]

Is this just to keep it running or turn the starter motor?

[Hackentosher]

If I remember correctly, caps don't hold voltage that well over time, a lead acid is probably a better choice.

[klh2000]

Six Maxwell 350F 2.7V in series should work fine for an ATV. The should hold a strong enough charge for about a week at a time. Does your ATV start after a short amount of cranking, or does it take a while to start? If it takes a while, you might just have to go with a lead acid battery.

[xwrench3]

it usually starts good, except after sitting for months at a time. which happens mostly because of the bad battery. once it has run enough to get fresh fuel, it starts well. even in 0 degree weather. if its colder than that, i am not going out in it! lol. any idea how well a supercapacitor battery would work for operating a winch? i use it for snow plowing quite a bit in the winter. 

[Andrew Storlie]

just make a battery pack out of 18650s, thats what i have my jeep running on, and i have a 1500w system with a bunch of led bars and shit. 4 18650s in series is 14.8v, perfect for your alt to keep topped of and then you simply run 4 packs in parallel to get the desired AH. im running a 4s20p pack of 3000mah inr cells, gives me about 400amps of max draw if i need it and a good 60ah capacity. 

[corrado33]

There is a reason we don't use supercapacitors for car/atv starter batteries. This question comes along every month or so on electronics forums. 

 

Lead acid batteries have great capacity for their size. They also have very low self discharge and HUGE CCA (cold cranking amps).

 

AKA lead acid batteries are GREAT for starting internal combustion engines. If your battery is dying, then go buy a $20 "battery tender" and never worry about it again.

[xwrench3]

i am afraid its far to late for a battery tender.  it needs a new battery. once a new one is installed, a battery tender will help. 

[Hackentosher]

Caps can usually discharge a hefty amount of juice, check out afrotechmods' super cap video. Also don't use lithium for your batteries as lithium cells don't like being fully charged or completely drained for long periods of times. Also you can completely flatten a lithium cell as that will damage the battery quite a bit. 

[xwrench3]

i see capacitor jumper "batteries" for sale for cars all the time. which was part of the idea i had for building a supercapacitor battery for this. light weight, andi was thinking it would last much longer. but apparently that is not the case.  /   i see they make lithium batteries for motorcycles now. but @ around $200.00, they are to much for me to buy. i am cringing at the $80.00 for a regular MF battery.  

[corrado33]

On 11/1/2016 at 6:30 PM, xwrench3 said:

i see capacitor jumper "batteries" for sale for cars all the time. which was part of the idea i had for building a supercapacitor battery for this. light weight, andi was thinking it would last much longer. but apparently that is not the case.  /   i see they make lithium batteries for motorcycles now. but @ around $200.00, they are to much for me to buy. i am cringing at the $80.00 for a regular MF battery.  

You know, you could probably just... charge... the battery. With a battery charger.

 

If you don't have a battery charger just find a 14 (ish) V DC power source and connect it to the battery. (Maybe put a resistor in series at least until the battery's voltage is up around 12V or so, so you don't break the power source.)

 

The battery in my car has gone flat many times over the last... 5-6 years. I just charge it up with my battery charger and it works fine again until I leave the lights on or something. 

 

Seriously, buy a battery charger. A lead acid battery that is drained is not DEAD, it just needs charged.

 

Heck, if the quad uses a 12V battery, just jump it with jumper cables from your car. (It's probably a 6V battery though.)

[Mira Yurizaki]

Let's assume batteries on a vehicle are just for starting it. If the alternator in the vehicle isn't enough to power the accessories, then you should get a new alternator. But I digress.

 

So pulling some figures from the internet, a typical car battery will discharge 500A for 30 seconds. And if this converter (http://www.convertunits.com/from/farad/to/ampere+second/volt) is correct, 500A/12V means you need about a 41.6666... Farad capacitor. For one second of discharge. So for 30 seconds of discharge you need a 1200 farad capacitor.

 

Oh, I found one: http://www.mouser.com/ProductDetail/KEMET-NEC-Tokin/S301RP128R2R7W/?qs=sGAEpiMZZMuDCPMZUZ%2bYlz4kwBPkogbTZFLJFZK4qbU%3d

 

Except it's rated for 2.7V, so you'll need to daisy chain them (Going from this, http://www.electronics-tutorials.ws/capacitor/cap_7.html , the voltages of capacitors in series adds up)

 

Disclaimer: I'm no way a professional at this so take this as you will.

[xwrench3]

On 11/3/2016 at 0:22 PM, corrado33 said:

 

On 11/1/2016 at 8:30 PM, xwrench3 said:

i see capacitor jumper "batteries" for sale for cars all the time. which was part of the idea i had for building a supercapacitor battery for this. light weight, andi was thinking it would last much longer. but apparently that is not the case.  /   i see they make lithium batteries for motorcycles now. but @ around $200.00, they are to much for me to buy. i am cringing at the $80.00 for a regular MF battery.  

You know, you could probably just... charge... the battery. With a battery charger.

 

If you don't have a battery charger just find a 14 (ish) V DC power source and connect it to the battery. (Maybe put a resistor in series at least until the battery's voltage is up around 12V or so, so you don't break the power source.)

 

The battery in my car has gone flat many times over the last... 5-6 years. I just charge it up with my battery charger and it works fine again until I leave the lights on or something. 

 

Seriously, buy a battery charger. A lead acid battery that is drained is not DEAD, it just needs charged.

 

Heck, if the quad uses a 12V battery, just jump it with jumper cables from your car. (It's probably a 6V battery though.)

 

unfortunately, the battery is junk. it is sulfated. meaning that crud had built up on the plates that will no longer allow the chemical conversion of acid to voltage. at least that is the best that i can explain it. the buildup looks like corrosion on aluminum. a white scale that keeps the cell from working. it is very common on small motorcycle type applications that go for long periods of time without use. i have seen, but i have never known anyone who used, something called a battery desulfinator. it is "supposed to " return the plates to an almost new condition by pumping in pulses of electrical energy of different power and frequency. problem is i have seen way to many things that claim they can do something, that do little more than lighten your wallet.  it is 12 volt. but this type of vehicle has a fragile electrical system. jumping it from a car that is not running is ok. but if the car is running, the chances of all that power from the car alternator can destroy the entire charging system in just a few seconds is quite high. i have seen a complete charging system ( alternator, voltage regulator, rectifier, battery, and wiring harness ) destroyed ( burned up ) simply by adding a high output headlight bulb!  i was actually a motorcycle mechanic before i destroyed my back 12 years ago. i did finally break down and buy a new conventional replacement battery for it. and as soon as it is back in stock at my local store, i am going to buy a "Battery Tender" charger, that keeps the battery fully charged at all times, without over charging it. i have cooked a battery or two to death in the past, with just a 2 amp charger!  but this will still be churning in the back of my mind. i have a 1968 Triumph motorcycle that has a battery eliminator (old school condenser)  that allows me to run the bike without a battery. it stores enough power to run the ignition coils only long enough to start the engine (kick start only back then).  since my atv has an electric starter, i need more power than that can provide. otherwise i would be heading over to the nearest Triumph shop to get one of those.