Power a Flashlight With Fewer Batteries in an Emergency

Picture of Power a Flashlight With Fewer Batteries in an Emergency

Don't let the zombie apocalypse or a power outage leave you in the dark. It's easier than you might think to keep your flashlight and other battery-operated devices running even without the proper number of batteries.

When you've finished with this instructable feel free to check out my website and YouTube channel for more how-to's, tutorials and life hacks.

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Step 1: Watch this video!

It's only a minute long and you can watch me demonstrate every step!

Step 2: What you'll need

Picture of What you'll need

This is a fairly simple instructional with minimal material requirements. After all it is for emergencies.

All you'll need is the device you'd like to power, at least one battery and some aluminum foil.

Step 3: Aluminum foil

Picture of Aluminum foil

First you'll need to tear yourself a sheet of aluminum foil. For a flashlight that uses D batteries I got a piece about sixteen inches long.The amount of foil used doesn't have to be exact; just get as close as you can. This emergency technique will work with other battery sizes, but the amount of foil used may differ. Once you understand how it's done you'll be able to easily figure it out on your own.

Step 4: Folding the foil

Picture of Folding the foil

Fold your foil sheet in half the long way. Smooth it out and then fold it the long way a second time. Don't worry about super clean, smooth folds. A good-looking sheet of foil isn't necessary, and in an emergency it's unlikely you'll be taking your time.

Step 5: Size

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The beauty here is that nothing needs to be exact for this to work, just close. After the folding is complete you should have a long strip of foil that is slightly taller than the battery you are using.

Step 6: Roll a foil tube

Picture of Roll a foil tube

Now It's time to roll! Just pick an end and roll your foil strip into a tube. No need to have your tube be the exact girth of the battery, just make sure it's not too thick to fit into the flashlight and you should be good to go. You can see in the last picture that mine was a fair bit thiner and taller than the actual battery but it still worked perfectly.

daveand511 months ago
not wanting to sound negative but
if the foil contacts the case and + terminal, by by battery
if too thin, it can tilt or crush becoming unusable
my idea would be to place a smaller penlight led flashlight inside a larger flashlight capable of also holding a second set of batteries, match tube, etc (like a large 3 d cell flashlight)
just saying you never no what or how long the emergency will be, so be prepared like the boy scouts say.
TamS111 months ago

Bravo ! Another tip for my _"the big one" (earthquake. I'm on the West Coast)_ bug-out backpack. Good info, thanks ;-)

samalert11 months ago

I may have a aluminium foil but not battery intrigues me.

akreitlow11 months ago
Wouldn't the battery knock back and forth, slowly flattening the aluminum foil ? probably use something sturdy to reinforce the foil. Cardboard, small pipe.
ch511 months ago

To make it even more usefull, what I like doing is permanently downgrading the bulb on a big maglite to accomodate 1 less battery than what it took initially ( a 3-battery bulb in a 4-cell lamp for example), and then replacing the missing battery with a small container containing a basic survival kit topped with a strip of aluminium tape for conductivity and sides wrapped in duct tape.

That way you mostly loose battery lifetime, but not much brightness, and will never be caught unprepared :) .

randki2411 months ago

good idea.

PhilsTj11 months ago
Good idea. One question though. Can I still use the tin foil to keep my cookies from sticking to the pan?
乌鸦drop11 months ago

so cool

cTsVette11 months ago

This probably won't work with LED flashlights as most of them require a certain amount of voltage to work, but for all the incandescent types it's a good trick to keep in mind.

MIK3 H11 months ago
Very good! Bravo bravo im going to try this out thanks! Pretty cool
The Best Hobbies Blog (author)  MIK3 H11 months ago

Great! Always helps to have done it before.

Carleyy11 months ago

Cool hack!

The Best Hobbies Blog (author)  Carleyy11 months ago

Thank you!

jon_chalk11 months ago

Very well documented. Good work. I clicked on "favorite" for this one.

The Best Hobbies Blog (author)  jon_chalk11 months ago

Glad to hear it=]