This cool flashlight runs off of almost any battery you'll find in your home's junk drawer

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There just might be a Nobel Prize in Economics for Panasonic here.


In a pinch, with enough aluminum foil, almost any large flashlight will run a smaller battery, or just one battery.


Will it run off dead batteries? ‘Cause every time I dig through the collection of variously sized batteries in our junk drawer, they all turn out to be stone dead.


I’d be impressed with an any battery flashlight that had a voltage regulator circuit and could run off of any battery within a decent range. then you actually could salvage batteries from all sorts of things to power your flashlight.

I am not THAT impressed with a flashlight that only runs on 1.5v batteries of different capacity size.
They ALL do that. You can use these 1.5v interchangeably, you just have to connect the battery to the connectors somehow, like wires and tape. or tinfoil. or…

i had some plastic upsize adapters that converted smaller sizes to D, but less and less of my items use any size of these types of cells anymore. for example, the flashlight on my desk has a 18560 3000mAh 3.7v li-ion battery in it. my main remote takes pill batteries. the battery scene really has changed in the last 6 years.

does anyone make a real any battery flashlight that anyone knows of?

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Hmmm…the chance of me accidentally finding a D battery floating around my life is pretty close to nil.


Not 100% off-the-shelf but this is mostly in the spirit of what you asked for:


Nope…but I’ve had a few dynamo flashlights. No battery required, just twirl the charging handle occasionally.

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have you had any self powering flashlight that was any good?

I had a squeeze one that required constant squeezing for a dim light and was basically useless.

I’ve had two of the, excuse the term, jack off style flashlights, where the slide weight powers them, but again hardly any light for a lot of really embarrassing hand motions that also make the light beam hard to point at anything.

I’ve had an led lantern with a crank handle that was a bit better but maybe i’m just doing something wrong, or maybe they’ve gotten better recently or i’ve just had crap kinds, but a flashlight that can power itself is the dream since the invention of the solar powered flashlight! :stuck_out_tongue_winking_eye:

when my crank handle lantern broke, i fantasized about adding a spring and gear wind up kinetic storage system, but it isn’t efficient enough yet, or my wasn’t, to gear to anything reasonable.

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I had a decent squeeze one in ye olden days before LEDs; it did require constant use of the squeeze trigger, but was well enough engineered that you could keep that up for a few minutes without much trouble. Not what you’d want for your primary light source, but useful as an emergency backup.

The concept is a lot more practical with modern LEDs, as they’ll run for a useful amount of time before requiring recharge. But the engineering is key; if the charging handle is made of flimsy plastic crap, it’s going to get broken very quickly. You want something that can cope with repeated vigorous cranking.

Still more of a backup than a primary, though.


Here’s something new - a glowing review of a product the reviewer has never actually seen.

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I have an LED worklight with a rechargeable battery that lasts 8-20 hours depending on how bright you set the lights. I make sure to top off the charge every six months. It’s a bar with 80 LEDs on it and it really illuminates a room very well.

I bought this hand cranked light about 2 years ago

It has stood up to a lot of use, including over aggressive cranking by toddlers who love to play with it, and it shows no sign of failing any time soon.

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Depending on whether you mean mostly dead or all dead some LED flashlights can actually perform pretty respectably.

You don’t get something for nothing; but an LED will just keep emitting roughly its rated wavelength more and more dimly as the battery dies; while incandescent bulbs slide into infrared as the filament cools; leaving you with pretty useless output from batteries incapable of providing enough current to keep the filament hot.

That said, flashlights don’t always exhibit this behavior; the ones that have a driver circuit between the battery and LED often shoot for uniform brightness followed by a hard cut off, though not all.

Definitely a thing worth testing for a flashlight explicitly aimed at using the batteries you have rather than the batteries you might want or wish to have at a later time; since that collection probably will include a bunch of batteries in dire condition (especially now that so many widgets that used to take a standard battery of some description have a little li-ion pouch embedded somewhere; the household battery stash just isn’t what it used to be; and if you are explicitly buying batteries for your flashlight you can get something a lot less gigantic than this thing.)

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Does it have a slot for plugging in lemons?


Or a potato?

The authorities will be cracking down on that!

“Fear is a strange soil. It grows obedience like corn, which grow in straight lines to make weeding easier. But sometimes it grows the potatoes of defiance, which flourish underground.”

― Terry Pratchett, Small Gods

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The IKEA hand-cranked flashlight is very good. Nice action, nice output, works for years. Not the brightest light, but perfectly adequate for 99% of the stuff you need a flashlight for.


You watch out, that potato might have GladOS inside.

Swear by these old mantle lamps for my home emergency prep. Lots of light - and the lamp oil is fine for apartment style living storage. Quiet. A couple of bottles tucked away - three lamps.

No worries.