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Make an Emergency Phone Charger – MacGyver Style!

Make an Emergency Phone Charger – MacGyver Style!

There’s no charge for this electricity. In
this project we’re making a 40 watt hand cranked generator from these common household items. For this project, let’s see if we can make
an emergency cellphone charger out of a cordless drill. I have a USB charger that charges this phone from a USB port, and we don’t really need the USB head, so let’s go ahead and cut
that off, then use some wire strippers to remove this outer layer. The shielding can
be pulled back, revealing the 4 wires inside. I’ve done this to both ends of the cable,
and stripped the plastic from the ends of the wires. Most phone batteries need around
5 volts to charge, and we can confirm that by plugging the USB head into the port, and
attaching some alligator clips to the red and black wires. Using a multi-meter, you
can see just over 5 volts of direct current. With the phone in series, the circuit is completed
when these wires touch and the phone senses power and lights up. This little black plug
symbol shows that it’s charging, and it only appears when the phone gets around 5 volts.
Ok, Let’s build our make-shift phone charger. I have a cordless drill I think I can convert
into an electrical generator by running it backwards. I’ll remove the bit, take the battery
out, and looking up into the handle, you can see the two terminals where the battery would
connect. For testing, I’ll attach alligator clips to both of them, and then connect the
leads to my multi-meter. When I pull the trigger and twist the rotating end of the drill I’m
generating around 5 volts, and that’s what we need. To make this into an emergency cell
phone charger, let’s round up a piece of scrap 2×4, a wooden fork, a ball of yarn, a mixing
beater, a roll of tape, and some aluminum foil. The first thing we’ll need to do is
secure the trigger in the “on” position. It won’t work unless this button is fully pressed,
so let’s use plenty of yarn to secure that, then fasten the drill to the 2×4 with as many
wraps as it takes to hold it tight. The mixing beater gets inserted into the drill chuck,
and when it’s fastened in tight we can double check there’s no slack when it rotates.
We’ll need the torque setting to be at it’s highest, and confirm the drill is set to reverse.
Now it’s time to rig the electrical system. Let’s rip this sheet of aluminum foil in 2
strips, then fold them into makeshift wires. You can use copper wire if you have it, but
aluminum is still a good conductor, and this foil will work in a pinch. These ends are
being rolled to a point, and these other ends folded over to make them a little thicker.
Now the flat ends can be held in place under the terminal clips of the drill, and since
we made these wires so long, let’s use the extra length to make sure they’re well separated
because they’ll short out if they touch. A little tape will hold those temporarily, until
we can add some yarn to fasten them in place. The red and black wires are stripped down
about an inch, and for this phone, we don’t need these wires at all. So one cut and they’re
gone. Now the red and black wires are attached to the aluminum leads, respecting the polarity
of the drill. In this case, red is our positive, and the black is our negative. The wires are
secured with some more yarn, and all we need now is some leverage for our crank handle.
My wife’s salad fork will work, and now that we’ve got our handle, I’m thinking this is
ready for a test. I’ll start cranking to see what happens, and look at that, the phone
lit right up. It’s showing the little plug symbol, so we know this is charging, and if
I stop, the symbol goes away. It looks like it’s working great, so I’m gonna take this
inside and clamp it down to a table for better leverage. The crank handle gets inserted,
and the system is powered up. The charging symbol is flashing which means I need to crank
just a little bit faster for stable power. And there it is. I’m cranking this at about
100 RPM to develop the 5 volts this phone needs to charge. If I crank slower, the phone
won’t power up, and if I crank too fast, I risk damaging it. Just for the challenge,
I’m going to see how long it takes to re-charge this battery from its completely discharged
condition. It seems to be taking quite a while, but when I think about it, it takes quite
a while even when it’s plugged in with a charger. I’m coming up on 3 hours, and I just saw the
charging symbol flash off. That means this battery isn’t accepting any more charge. It’s
done. I can disconnect the charger cable and this phone is fully ready to go. If this electrical
generator will charge a phone, I’m wondering if it will recharge a battery. I’ve added
metal magnets to the ends of a rechargeable AA battery, so that my alligator clips will
attach easily. By attaching the same wire to both ends, we’ve shorted it out, and the
charge is being drained as quickly as possible, and I can feel the battery getting hot. This
battery is completely dead now, so to revive it, I’m adding these lead wires in parallel
with the system, and connecting them to their respective terminals. It takes about 15 minutes
of cranking, and it’s harder to turn the handle this time, because I’m pushing a larger electrical
current into the battery. Alright, it’s done, and a quick test on the meter shows that the
battery is fully charged. Well that was educational. I tried shorting the system out on my meter,
and got about 6 volts at 7 amps. That’s over 40 watts of power. I also tried hooking up
an incandescent flashlight bulb, and got it to fully illuminate. A white LED was also
tested, and was so bright it actually hurt my eyes to watch. Well there’s a makeshift
electrical generator that you can make in a pinch, that will charge batteries, illuminate
lights, and generate around 40 watts on human power. And it’s free. That’s it for now. If you liked this project, perhaps you’ll
like some of my others. Check them out at

100 thoughts on “Make an Emergency Phone Charger – MacGyver Style!”

  1. As much as I like your newer videos, they aren't terribly useful. Just neat stuff.

    This on the other hand, this is useful. I can see this scaled up with a stationary bike and a fan motor (or even a washing machine motor!) to recharge something like a motorcycle battery very easily.

  2. I tried this same thing, and couldn't really get more than 0.5V @ 2amp, cranking that thing at full-speed. Any ideas what I might be doing wrong?

  3. He said that he rotated the spoon at about 100 RPM (rounds per min). So if he sat there spinning that spoon for 3 hours, it means that he spun that spoon about 18,000 times.

  4. Why not just use the drill battery in an emergency just dismantle and remove some cells to lower the total voltage

  5. I know this is old, but I'm curious how much force you are having to use to rotate the motor? Like psi or at least using a fish scale to measure the force?

  6. Be careful. Newer phones sense the variation in the voltage and will automatically turn off the charging which will likely cause you to fry the charging circuit. You can fix this with a five-volt regulator. =)

  7. If you had any string left you could wrap that around the egg beater and pulled. Would likely spin that drill a little faster for more voltage. Maybe only take an hour.

  8. Car batteries every where, Lithium ion batteries every where. Why on the earth people wants to make phone ineffecient chargers

  9. I actually used this during a power outage from a tornado. Saved my skin and tbh without that I'm not 100% sure what the outcome would've been

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