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I am attempting to build a really cool thing (at least I think).

The goal is to build an arc lighter that I can shake to charge (kinetic power).

It's a circuit that combines an arc lighter circuit with a 3.7V input, a supercapacitor to power it instead of a lipo battery, and the power system of one of those "shake-to-charge" flashlights from the '90s. Here's what those flashlights looked like:

shake to charge flashlight

I'm really only an electronics hobbyist and have never really designed a circuit board before, but I've been learning EasyEDA and have gotten decently proficient.

As far as I know, I need to combine the arc lighter circuit like this one: circuit Increase Arc Lighter Spark Gap

with this power circuit: https://i.stack.imgur.com/DxCC3.png

and also make sure I choose a super-cap with enough storage to fire the spark for at least a few seconds if not longer.

My question to you guys, among others, is: Is this feasible, and if so, where do you suggest I start?

Any and all advice is valued and I am so grateful to have found a community where electronics wisdom exists and I can ask questions. Thanks!

edit: I did some power requirement math and put it down below. So far you guys have been so helpful. Thanks for everyone who’s helping in any way!

I found a brand of arc lighter that put their tech specs in the FAQ on their site and figured I'd start with that: https://www.arclighter.com/arclighter-faq

“[the lighter] …can light 90 times on a single charge based on 8 seconds per light.”

8 seconds per light x 90 lights = 720 seconds of arc firing per charge

“What are some of the charging characteristics of the [product name]? Nominal Capacity: 450mAh Input: 3.7V Output: 6A“

450mAh@3.7V / 720 seconds

0.625 mAh per second @ 3.7V

Converted 3.7V 450mAh to Joules: with (mAh x voltage x 3.6 = Joules of energy)

~6000 J of energy per battery

6000 J / 720 seconds

= 8.3J/second while firing the arc (for this brand of lighter)

I have to keep in mind I will not be using lithium batteries and instead using supercaps. I have no idea if there are any negative ramifications other than not needing lipo charging circuitry, and I can instead use a Zener Diode to prevent capacitor overcharging.

Mike Hernandez
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  • Start with some rough calculations. (1) How much energy (joules) is required for your arc. (2) How much energy can you generate with, say, a minute's worth of shaking? (3) Answer 1 divided by answer 2 will give you a rough estimate of the amount of shaking required per arc. You'll probably have to make some measurements and then hit the edit link below your question ... – Transistor Jan 03 '20 at 00:00
  • @Transistor Thanks! I did a little math and got 8.3J/second of power draw from a commercially available lighter. – Mike Hernandez Jan 03 '20 at 00:22
  • You could try taking a T1 from another spark lighter, flipping it around, and connecting that (primary) in place of the coil in the shake-light. This might be most-efficient, but still there will be lots of loss due to using two transformers. – rdtsc Jan 03 '20 at 00:25
  • Do you want an igniter or an arc welder? – Tony Stewart EE75 Jan 03 '20 at 00:43
  • Thanks so much for the input! Just to clarify, I'd be wiring T1 from the lighter in parallel with the inductor coil from the flashlight? Or I'd be removing the coil altogether and replacing it with T1? I'm a little confused about what this would look like and how it'd work. Apologies, I'm relatively new to the (grown up) EE stuff and mostly only made my circuits by trial and error as a kid. @rdtsc – Mike Hernandez Jan 03 '20 at 00:44
  • An igniter, something high-frequency that can ignite a cigarette or cardboard to start a fire. Something not too scary. I'm an eagle scout and I go camping often, I'd like to be able to start camp-fires with electricity off-grid. @TonyStewartSunnyskyguyEE75 – Mike Hernandez Jan 03 '20 at 00:46
  • I suggest you search for "igniter tear-downs" to understand the schematic , materials and aircore coil – Tony Stewart EE75 Jan 03 '20 at 00:58
  • You'd want to mate spark-end to spark-end, then the free terminals in place of the inductor coil in the flashlight. (Essentially you're un-doing what the spark transformer is doing - converting high voltage back into low voltage.) – rdtsc Jan 03 '20 at 12:49

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