Fluorescent Light, Powered By Battery


If you’re going camping this summer, or just want a cheap emergency lantern powered by a pair of AA batteries, you probably can’t do much better than [rimstar]’s Joule thief compact florescent lantern.

The circuit for [rimstar]’s battery powered CFL bulb is a Joule thief. While these circuits are usually used as a demonstration to get every last bit of energy out of a battery with a LED, [rimstar] upgraded everything with a better transformer and a power transistor to light up a CFL bulb.

What’s really interesting about this build is it provides a use for blown compact fluorescent bulbs. The normal failure mode of these light bulbs is usually the electronics going bad, not the tube. By replacing the electronics with a homemade circuit, it’s an easy way to reuse these broken bulbs.

Video below.



42 thoughts on “Fluorescent Light, Powered By Battery

  1. I remember when I liked toying around with high voltage things of this sort (joule thief, slayer exciter). It got boring when I realized that it’s practicality ended at lighting things up.

        1. I think you find they use high voltage for other things tan lighting things up out there.

          I name some random ones: Making objects statically charged or ionizing air or zapping bugs, and there are high-voltage speakers too. Point being that there’s more than just lights.

          1. I run a small, inexpensive chemistry lab on a sniffer dog training farm, for producing pure smells. That implies doing some organic chemistry. To test my substances for purity, I sometimes do thin layer chromatography. To see spots on the chromatograms, I use an ultraviolet fluorescent lamp which makes the background of the thin layer glow green, with dark spots where the substance absorbs UV. I ordered said lamp from a well known American chemical supplier, and it takes about six weeks to get here in South Africa – it is a real pain in the butt. The lamp looks like a cheap camping type, with a window cut into the plastic lamp cover for the UV, but it costs an arm and a leg. The only other special item is the quartz glass lamp tube. So the single SS8050 transistor in the driver circuit melted – it was shorted from collector to base to emitter. I replaced the transistor with a BD139 from my box of spares, and it is working fine so far. I found this web site out of curiosity after the repair, because I like to understand things. So I can report a very handy and relevant application for this simple circuit, even though it is somewhat esoteric. UV LEDs only emit in the near ultraviolet, but thin layer powder needs 254 nm from the mercury emission spectrum to fluoresce. Thank you for showing me this simple circuit.

          1. I guess you mean lifter. Have you seen anyone do that? I’d think that both the voltage and current would be too low. My smallest 2 gram lifter needed around 26kV and 275uA. In my second video above you can see the output of this joule thief is no where near that. However, I recall lifter experiments in the early 2000s where it was found that 70Hz pulse HVDC was exceptional but I don’t recall the voltage or current. It’s certainly an intriguing idea though.

    1. Ricksl and others please let’s say I want my slayer exciter vacuum tube instead of solid state. (Yes I can provide filament voltage) I have all kinds of boxes of good tubes. Suggestions for tube type and circuit modification. Thank you

  2. This design is quite common in electronics magazines, I remember making it for driving 40W fluo tube with car battery, I was using ferrite rod scavenged from old radio receiver. The bigest problem was winding the secondary coil, it required around 500 turns and if you weren’t careful high voltage could burn wire insulation and render transformator useless. Since it uses HV all the time, starting circuit and filament heating was not necessary so you can use fluo tubes with broken filaments. Design looked something like this : http://joey89924.wordpress.com/2013/05/21/12v-6-12-watt-fluorescent-tube-neon-lamp-inverter/

      1. You can also shove an old plastic waterbottle over it to both protect it from damage and capture emissions if it does break, at least long enough to remove it from your presence.

  3. I don’t know why people are so worried about mercury. I used to play around with the stuff when I was young, and I’m perrfctleee Nrrrrrrrrrrrrrrrmll ll ll

    1. Truth be told it does take a lengthy expose for a human to be affected, but it’s also poisonous to other lifeforms and can mess up the groundwater, so in that sense you do want to contain spillage

      1. Mercury is accumulated in the body, several small exposures are just as bad as one big one.

        The hack is a great technical build even if the end result is rather useless compared to just using a LED. But who says fun builds have to end up in a useful end result every time?

        1. That’s why I did it, even though I knew LEDs would be better. It was just too much fun thinking of carrying around with a lit, wireless CFL in my hand, the fact that it was a CFL being the fun part.

  4. everyone here should learn DIY fluorescent drivers

    if theres an EMP and 99% of your semiconductors(in the field) are fried, theres still a very good chance your glass tube is fine. the EMP is only a split-second and would not have enough time to heat the tube to breakage/burnout

    the EMP/highvoltage will start the tube into conduction, at that point it might as well be a piece of metal and will get the full current of the EMP BUUUT the EMP will not last long enough to melt the glass!

    if 99% of all semiconductors in non RF-sealed/lightning-proof enclosures are fried, then theres (in my opingion) a 50% chance that transistors in RF-SEALED/lightning-proof (storage) enclosures may still be operational.

    thus allowing you to build this project and be the ONLY individual in a 50km range with a WORKING non-incandesant electric lamp

    PS: when i say RF-sealed/lightning-proof i mean a METAL enclosure with ZERO holes and ZERO wires protruding. that means ZERO viewing windows or swtiches. in other words a (closed) ALL METAL toolbox ect

    PPS: LEDs are just as susceptable to EMP as a standard transistor
    … EMP = 50kv / inch so 25kv into a half-inch LED == will not survive!

    1. Hot gluing the battery pack to the potentiometer was to hold the battery pack in place, rather than the other way around. The potentiometer is attached to the plastic jar and the battery pack is attached to the potentiometer. I guess it could have been done any number of ways.

  5. Re. EMP, LED’s aren’t quite as sensitive as believed.
    I’ve actually tested this, nuked an infrared LED in the microwave and despite lots of bright light and sparkage the LED still worked as well as it did before.
    White, blue and green LEDs don’t survive very well but red and IR do for some reason and this also holds true for HV overvoltage.
    I’ve also had some success with reverse pulsed bias to “unmuck” dead blue LEDs and laser diodes where they read about 50-80 ohms in both directions, sometimes works if you limit the current and keep the pulses short.
    I think the mechanism is that 90% of the junction is intact so blowing out the bad area sometimes isolates it allowing the rest to function again.

    For those who want to make their LED lanterns EMP proof, the recommended fix is to connect a 47K resistor in parallel with the LED and this makes them work even if zapped with a Tesla Coil.
    EL wire is also somewhat immune to EMP.

    1. Mine didn’t light the CFL with 1.5v either but did when I added another battery in series for 3v it worked. As you can see in the second video I even ran it with 9v. So I’d suggest adding a 3rd battery for 4.5v and even a 4th if that doesn’t work out.
      Did you use thickly insulated wire for the last few turns of many-turn coil and also thickly insulated wires for the other coils. If you used only enameled wire then it’s possible you’ve already damaged the insulation and that’s why it’s not working.
      How many turns did you put on the many-turn coil? Do you have an oscilloscope you can look at the output with like I did in the second video? That way you can at least see if you’re getting some high voltage on the output. Also, what wattage is your CFL? It’s easier to get a lower wattage one going since the path is shorter.

  6. They are licensed in the mechanical and electrical fields, as well as fire protection contracting.
    Due to its large size, the only matter of concern with a commercial system is to maintain it regularly to
    avoid catastrophic failure in the future. However,
    instead of using a standard electrical compressor and motor, a thermal
    compression system is used.

  7. I hate the fact, that we throw out poisonous CFLs just because heating filament gets broken, while everything else is ok… CFLs can be still lit without these filaments… Just bad CFL design? CFLs are made to die. There are two filaments, so it’s probably twice more likely for CFL to die than for classical incadescent lightbulb. Can’t we ionize CFLs using something different? (Well we still have LEDs and expensive induction based fluorescent lamps that will last virtually forever)

Leave a Reply

Please be kind and respectful to help make the comments section excellent. (Comment Policy)

This site uses Akismet to reduce spam. Learn how your comment data is processed.