Generate spark


I want to generate a spark or fire to light up Hidrogen using arduino. I know arduino does not have the power to do that, I will have to use a mosfet and an external power source. Can I generate this spark using 9v battery?

I am currently using a resistor of 100ohm and connecting it to a 9v battery and see it get fire. When it gets fire it fires the Hidrogen and works well but I need to change the resistor every time I ignite Hidrogen.

Any reusable suggestion (cheap)?

Model rocket fuses might be the obvious choice here - they will be designs out there for that sort of device. Or a thin strand of copper wire.

Reusable means a spark generator, ie a car ignition circuit (these days an IGBT circuit is often used). This requires a suitable (auto) transformer coil. Remember such circuits generate potentially lethal high voltage spikes.

Does it have to be electronic? What about a peizo sparker like what's used in grills?

The “secret” to getting a spark is a coil/inductor to create a high voltage and a spark across a gap. Inductors “resist changes in current”.

When you apply voltage to an inductor (relatively) low current flows for a short period of time while the electromagnetic field builds-up, then the current becomes constant.

If you suddenly break the circuit, the electromagnetic field collapses and high voltage is generated as it tries to maintain current through an infinite resistance.

I don’t have a feel for what inductance you need, but you MIGHT need something “big” like [u]this[/u].

Some people take apart the flash from a disposable camera. (The strobe uses a couple-hundred volts.) But, can you still find disposable cameras?

A couple of things about a “basic circuit” like this - You’ll waste lots of current& power if you leave the coil connected to DC for too long. And, if you use a switch or relay you’ll get an arc across the switch contacts (maybe across the switch instead of across your spark-gap) and this will quickly deteriorate the switch. In a car, the spark-coil is actually a transformer and the contacts (or electronic ignition) operate on the lower-voltage side so the spark goes to the spark plug.

Professional fireworks use disposable [u]igniters[/u].

Or, you might try a [u]piezo igniter[/u] which are used for model rockets or gas BBQs.

Possibly an Electronic Grill Igniter that uses a battery and generates sparks as long as the button is pressed, the kind you see on newer BBQ grills. Much easier than the Piezo type that makes a large crack sound. Should be able to hack the unit to replace the button with relay contacts. Amazon has them for as low as 5-6 dollars US.

Replacing the 100 ohm resistor with a little tuft of steel wool (driven by a MOSFET) will work much better than the resistor.

@DrAzzy from all the sugestions here yours I think is the easiest and cheapest to me. Do you think that using a tuft of steel wool would set fire in H? And what about in alcohol vapor?

Steel wool, if it's teased loose, will burn quite well and will easily ignite either hydrogen or alcohol vapor. The wool itself will burn up, however.


You can get an igniter from a dryer - though I don't know what power they require.

Hobby king Ignitor Box is the solution for this, HobbyKing Open up this box, control the switch with the Relay and connect the Spark plug with those wires.

How about a steel wheel on a motor that contacts a piece of flint?

I've found a silicon nitride igniter to be much more reliable than a spark for igniting a propane torch. The only downside is it takes a second to heat up but I found sometimes it would take a few sparks before ignition also.

I'm using this one: because I needed the small size but you can get them way cheaper in other forms. Check eBay.

I'm not sure about the alcohol but I'm sure it will work for hydrogen.

How about something like this? Allegedly converts DC 3.6V-6V To 400000V, and that should create a spark.

What about a platinum catalytic lighter? You need only to expose platinum moss, wetted with methanol, to air, and it spontaneously catches fire. Platinum costs a lot, but it will also last … well forever. We will collide with the Andromeda galaxy* long before it wears out.

Regular platinum wire or sheet won’t work - use either fine spun wire, thin moss or a very fine mesh. The catalytic action requires sufficient spots of contiguous surface area, so the quality of the platinum, as well as the total surface area (finer = more), is important. You might have some luck looking for antique lighters. They were very popular until the much cheaper iron/flint lighters were invented. And they are virtually indestructible, so if you come across one, you will be able to clean it chemically, if not with a good soaping.

* disclaimer: our atmosphere might change as a result of galactic collision, so there is no warranty.

What about good old nichrome wire? Used to use it to ignite model rocket engines:


It takes very little energy to ignite a hydrogen/ air mixture...

Look at the trigger circuits for photograhics flashguns.. the trick is the transformer - eg TOKO make them.



Five volts through a few centimeters of nichrome wire will do what the OP's 100 ohm resistor did--cheaper, faster, and reusably. I think somebody else earlier in the thread also mentioned model rocket igniters. Matches aside, nichrome is the original.

best, Michael

Do you need a spark or fire?

coz a chewing gum wrapper with the right shape will catch fire quite easily, even with a single AA battery. :)

electronic spark generator is the way to go,

the circuit is simple, just an oscillator driving a coil

finding a suitable small coil will probably be the main problem, may be simpler to modify something ready made.

here is a link to a youtube video that show how to modify a cheap gas lighter, the lighters are available on ebay for less than £10

the modification is only needed if you just want a single spark otherwise the circuit runs continuously .