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Battery to capacitor

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Hi folks, I am using four AA cells to give me 6v on a project. The battery pack is way too big for the application.
Is there a chance of changing the battery pack for a capacitor.
I will need to charge the cap too.
I am using the battery pack to activate a nicrome wire flash device, similar to a stage unit.
once charged it will be used within about ten mins to activate the flash
Hi Mike,
Once the cap is charged it will not be activated or swithed on till about ten mins and then it will be on for one second for each activation

Cheers for the feed back
You'll have to figure out exactly how much power you're going to need. How much power is taken in each "flash" and how many flashes. Then you can figure out what size cap you need.

The biggest problem with switching batteries for caps is that caps are TINY on storage compared to batteries, and as birdman said, they have terrible internal leakage too.

It's like putting a lawn mower engine in a car. You can do it, but you ain't going to get far.
Leakage depends on the design of the capacitor. I have unintentionaly left charged capacitors laying around for months and gotten shocked off of them when I picked them up.

For what your needing you may need an ultra capacitor or similar to hold enough charge. For the cost Vs what your needing to do it may still be cheaper to go with good batteries.
You could possibly combine the two ideas. Use smaller batteries with a cap in parallel to give you the large surge current required. But as stated earlier, more info, such as current and exact duration and frequency, is required before we could tell you the size of cap and battery.
if you compare the volumatic power density, to store the same power of 4 AA batteries you may need more space with capacitors. you better search for some rechargabe batteries that are small in pack and having 6V out.
Hope this description helps you folks help me.

I have copper tracking of 5mm width and 4cm length running in a parallel line on the inside of a cig box.
at the one end of the two lines I have the resistance wire bridging the tracks so that when I apply 6v (4 AA batteries) to the tracks the resistance wire glows and sets the flash wool off that is touching the wire.

The problem I have is that the batteries have to be concealed within a cig box?

Still holding a full pack of 20?

so I need to have a thin power supply that fits inside but will deliver the 6v, A larger voltage would not hurt as long as its does not blow the wire.

The wire is triggered by a push button switch or reed switch .
cheers all comments so far,
Need to know more about the resistance wire. It needs to be undamaged when you're done?

What is the current required to make it glow? (Or, what is its DC resistance?). How long does it take (5, 10, 50, 100 milliseconds?).
Sounds like you need a lot of juice for what is effectively a small glow plug
Have you bought the plug from a model shop... plane glow plugs work a treat
you should only need a couple of AA batteries... use rechargeable not pack bought
Flash cotton needs to be made furry and tampered gently down into your copper tube
use a tiny micro switch to ignite... best to also have a disarm/arm switch just for safety
Yes if possible the wire needs to remain in tact after the flash.

I am currently using a bank of 4 AA size batteries go give me perfect results as far as working voltage etc, but the pack is physically to big to be practical.

I have used the cap/bat out of one of those indoor helicopters and charged it using the six volt pack. on the side of the cap it says aec8111k ? I put a small led inline that goes out when I it is full.
I got nowhere when I did a search for the Cap online.

Someone sugested using a 10uf 2.7 super cap?:rolleyes:

Thanks for your tips so far guys I really appreciate it

Ian :)
Hi Gary,

They work great as far as performance goes. I want the power source to be hidden inside the box.
Imagine you are holding a pack of cigs and then you open the packet to show it is full. When my other hand comes over to take the packet a switch is activated and a flash is made. the cig box would be nice if it looks normal.:rolleyes:

hence the small or thin power source I am aiming for.

N size have been best so far in batteries though.

Cheers matey
can you sketch whats really in your mind about how it should look like finally? single battery with tiny circuit to generate high voltage and charging a capacitor then discharge the cap may be another option. but how can you again accomodate all these stuffs within a full pack of cig box.
It sounds like this is part of an Illusion - could you just cut the cigs in half and re-pack them on top of your battery pack? Flip open the top and you will still see the cigs. Also / Alternatively, leave a couple of the cigs full length so you could remove one with a flourish to give the impression that they are all full length?
Hi folks,
DamoRC that is a good idea :) will suffice for the short term many thanks so far.

Not a flash bomb I will be holding the box at all times.

mbarazeen, your idea sounds exciting I think you may have the way forward.

I can email anyone a sketch if it helps:)
Cheers again,
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