Introduction: Bicycle Cell Phone Charger (Wind Turbine With Build in Battery)

Picture of Bicycle Cell Phone Charger (Wind Turbine With Build in Battery)

I go very often to cycle in the nature where is no electricity, and during a long bike tour my phone usually discharges. These smartphones have a large capacity but its consumption is big too. I made a few weeks ago another bike turbine for the Bicycle Contest, but I think I can make a better one. So created an all in one wind turbine power bank.

I like to combine cycling with electronics (these are my favorite hobbies) so that's why I create so much bike gadgets now for the Bike Contest.

This project requires basic soldering experience and some patience.

The price of a device like this is very high on the eBay, 112 bucks!!! Click here if you want to see. OK, my one can't light and isn't so smart but this price on the eBay is ultrahigh.

The gadget was made from scrap parts and from very cheap circuit parts. Now go gather materials!

Step 1: Gathering Tools and Materials

Picture of Gathering Tools and Materials

• Soldering Iron
• Glue Gun
• Wire Stripper and Cutter
• Electrical Tape

• an old CPU fan
• toroidal inductor
• 2N2222 or 2N3904 or BC547 transistor
• 5v step-up module, (boought on eBay)
• germanioum diodes (5 pieces)
• a small perfboard
• an old phone battery or a 18650 cell
• and a small switch
• bike support element

And that's all. The fan generates AC current that we'll convert to dc current to charge up the battery via a Joule Thief circuit.The Joule Thief gives enough voltage boost for the build in Lithium ion battery. I don't use a charger circuit, because this current isn't enough to damage the battery.

Step 2: AC to DC

Picture of AC to DC

First take off the propeller, because we need to find two pins that gives the highest AC voltage. You can see three pins inside the fan. Solder to each one wire then check with a multimeter (in AC mode) that which two gives the best voltage. Remove the third wire that is unusable.

Put back the propeller, and create a diode bridge just like on the images. Connect this to your compter fan. Now the gadget could generate 4 volts and 60mA, that's almost enough for charging the li-ion battery. But using a joule thief we can get a very cool voltage for our battery.

Step 3: Joule Thief

Picture of Joule Thief

This step is pretty easy. Simply solder together the well-known Joule Thief circuit. If you're done connect it to the DC output of the CPU fan.

On the diagramm the 1.5v single battery means the CPU fan. And the LED means the battery.

Step 4: The Charger Unit

Picture of The Charger Unit

Hook up your battery and connect it to the 5v step-up module. Place between these a power switch. Connect this thing too to the Joule Thief's output. Now the circuit is done and device can be used, but we'll need to make them nicer.

Step 5: Glue!

Picture of Glue!

Get your glue gun and fix everything on the CPU fan's sides.

Step 6: Waterproofig

Picture of Waterproofig

Using some electrical tape waterproof the system. It isn't the best solution but do his job.

Step 7: Testing

Picture of Testing

The pictrure qualty is not the best but on the third picture you can see that it works. If works for you too go and put on your bike.

Step 8: Setting Up to the Bike

Picture of Setting Up to the Bike

Get a bike support element and glue oon the top of the device. Now you're done.

Step 9: Have a Good Bike Ride!

Picture of Have a Good Bike Ride!

If everything works just enjoy the free energy of your bike. I hope you liked and if you want give a vote for me! Thanks for watching :).


Chief.Wolfinjo (author)2017-09-08


can you give me link of 5v step-up module. I need to buy it.

thank you


; D

raywood (author)2017-07-11

I'd like to see it adapted to use a window fan mounted on the back rack. Power my TV as I ride. Alright!

profort (author)2017-07-10


SeamusFrederick (author)2016-07-26

I hear all the "professionals" in the comments who are going on about their engineering things and that's fine but dude for a 16 year old this is pretty cool..sounds like a fun project!

For a 14 year old this is cool!

Sukhpreet SinghK (author)2016-10-04

Can we use this without attaching a mobile bateery
I mean simply using usb port instead of the battery??

I would imagine, but without the battery you would probably not be able to keep a charge stored.

bikeboy111 (author)2017-02-10

My email is could you possibly email me we have a coupke questions including what you used to attach the fan to the bike?

alexfielder02 (author)bikeboy1112017-03-23

I believe he used an old bike bell mount.

alexfielder02 (author)2017-02-26

approximately how long does it take to charge?

the_blackhobbit (author)2017-02-05

Love the idea! You know what you personally need to advance in, and you do so. Naysayers are just parasites addicted to stagnancy, rather than the naked joy of experimentation! You know, there is a platform that supports those like you and I Tamas. It believes Creators have not been paid their worth near enough over the past centuries, so it allows their fans to do it for them. If you're interested, give me a ring why don't ya? They pay us to tell like-minded individuals like yourself about it. Keep on creating bud!

jayanth jayaraj (author)2016-11-13

what is the mechanism used in this project

RIGON1 (author)2016-09-21


wpe_15 (author)2016-07-25

kipkay though..

Yonatan24 (author)wpe_152016-09-07

This was published before Kipkay made his video.

SalmanA46 (author)2016-08-15

What about motorcycle ? Can we implement same idea on motorcycle

Thebraxas (author)2016-08-10

Heyyy we're planning to make this for our scientific investigative project, hmmm can i ask? What's the average speed you must go for it to power up?

Imetomi (author)Thebraxas2016-08-15

If there is wind 10km/h is enough.

evannatta (author)2016-08-07

lam looking for details about your products place leave a messages .When I post this , I am looking for more Information on this!

Imetomi (author)evannatta2016-08-15

Sorry, I hadn't so much free time these days.

Azzurro (author)2016-08-12

How many times do i see this in the newsletter again? I don't like the idea.

Imetomi (author)Azzurro2016-08-15

Then do not click on it... ;) For me it isn't a ptoblem if is not liked by every single user.

Gelfling6 (author)2016-07-26

I like the idea, but I may be ending-up in the "Engineer-Naysayers" group.. Most fans like this do not generate AC or DC out when run like this.. they are usually wired as a DC to stepper motor style (the DC voltage is sent through a circuit that turns on one coil, then the next, shuts-off the previous coil, then turns it back on as it goes around, turns off the 2nd again, alternating the two.) The chip (in picture 3 of step 2, with 4-wires) is a combination driver & Hall-Effect sensor. it doesn't generate any voltage.. The sensor is for making sure the impeller/magnet is spinning, and telling how fast it's going (tachometer). The coil & board pack are not easy to remove (I've tried.. they epoxy the daylights out of these, and you either snap the support post, or end-up snapping the wires to the coils. (and they usually solder the pins to the coil down tight to the board.)) Also, on fans with a 3rd of 4th wire (one is the tachometer output, but that is usually a powered signal from the DC voltage, the other is a resistor/temperature output)

If you can manage to get the board & coil off the frame without doing damage, You have a 3-wire, 2-coil (one common center) |^^|^^| , which you can wire to.. You can actually get the most voltage out of just one coil at a time, because of the magnet arrangement, One will be dropping as the other rises. (so wiring the two outside wires will give only half Maximum, and trying to wire the two outer ends will cause one to short (Collision style) the other as the voltages ride/fall.)

An AC fan (run by AC voltage, not DC) will not generate any, if VERY little.. the magnet is replaced by a stepped steel armature, and any magnetic field it has would be delegable.

I still like the idea! There's another plan here in the instructables, of a Quad-Copter made from E-Waste, But I wonder seriously, how they managed to modify the DC fans, to produce enough speed, for the same reason I mentioned about the epoxy holding things together.

Don't give up though! Note I said not easy.. I didn't say impossible!

Chrisbenedetto96 (author)2016-07-25

To all the people telling this writer who took the time to put this together that the idea is inefficient and all that, if you see a problem come up with a solution. For this devices intended purpose it is everything it was asked to be and more. Honestly when people complain that's when you know your onto something. You think oil companies told tesla they thought his idea was efficient and nice? More power to you. Don't let negativity dissuade your creativity. I'm sure light overcomes dark, unless you'd all disagree saying that lights are actually black hole singularities sucking light back up and anti illuminating the world one head light at a time. This place is supposed to be a network of support.

Try to be serious from time to time. I'm really sorry not being able to support such a project, but it cannot be supported as so many we see flourish these days. Recovering a few milliwatts by spending dozen of watts cannot be considered as efficient, no ?

Rafununu, everyone deserves support. Look to each their own. If you don't like it that's okay we're not here to bother you. Your looking at the numbers and seeing loss, this is understandable. Remember though. As it was, the bike expended energy anyway and in turn only created motion, this invention, while slightly parasitic, turns the motion of the bike through air into enough direct electrical current to charge a battery and store the harvested juice for later. So as a whole, their is a very practical use for this device, remember practicality and efficiency are related but are not the same thing. Personally, and this is just my opinion that you don't have to agree with, I think that I'd be happy to add the extra resistance from the fan if it meant that each time I peddled my bike I could look back and think to myself "finally I'm charging this device by my own raw work, and it is satisfying."

Imetomi, your very welcome, this place wouldn't be here without authors like you, I've completed many a project using information sourced from this place, so thank you for helping the cause and spreading your knowledge. If it works it's a success in my book. Id like to start sharing my ideas on here but first I must develop them more

Imetomi (author)Chrisbenedetto962016-07-26

Thank you very much! This is an old and not my best project, but worked, and I knew that there will be a few haters (shouldn't be liked by everyone), that's all right, but not on this site... :) Thanks again.

very well said. be nice people :-)

Capitan Thortellino (author)2016-07-25

But using it on a motorbike?

It will work a lot better .

Dakotamouse (author)2016-07-24

I won't be making this. It is way beyond my skill set. Even reading the comments makes my head reel! But I so admire your ingenuity! What a wonderful problem solving project!

Imetomi (author)Dakotamouse2016-07-26

Hi, make it! It isn't so hard, you will learn a lot and it is cheap. :)

billbillt (author)Dakotamouse2016-07-24

Can't never could do anything!!.. Don't be intimidated by this project!.. It is really quite simple.. This is how you learn.. By doing.. You will be able to do this with very little effort!...

007Y (author)billbillt2016-07-25

Yay +++ people

GeneB21 (author)2016-07-25

I see the "know it alls that do nothing's" are out in force on this one. I have actually seen these work. Pretty cool and given enough time and wind they will charge a cell battery. Even though these days there are much better,more efficient, low cost ways to charge things this is still gold if you have access to old muffin fans along with other old computer guts and you are in a pinch....the more you know the better off you will be in any situation, GOOD STUFF!

alzie (author)2016-07-24

Charging lithiums over 4.2V will damage them.
This really oughta have a voltage limit.
Thats why there are many specific lithium charging ICs.

uwezi (author)alzie2016-07-25

He will not be able to destroy (or charge) any lithium battery with this reverse fan. You might get a certain open-circuit voltage out of a "generator" like this, but there is no way it will deliver any significant amount of power (current times voltage).

You have just to compare a high quality hub dynamo which delivers 2.4 W with this fan - you cannot turn a wheel attached to such a dynamo by just blowing, yet riding along you don't notice the extra resistance. What happens with the fan if you actually try to extract power is that it will simply not rotate anymore...

alzie (author)uwezi2016-07-25

Yeah, hub gens are the way to go.
I use one, 3W shimano.
I barely notice the extra drag.
Hey, we re out for exercise any way.

uwezi (author)alzie2016-07-25

if - only if! - this wind turbine would be anywhere close to producing 2-3 W of electric power (which could charge a smartphone in a mere 3 hours) it would produce at least a comparable drag on the bicycle. Just imagine it dangling on one side of the handle as in the photos ;)

bobz8 (author)alzie2016-07-24

True, very true.

tommypc (author)2016-07-25

It is 36 bucks on Ebay.

JosiahC5 (author)2016-07-25

awesome, but isn't a reverse motor a generator?

rbclima (author)2016-07-25

You should put your generator in front of another fan and measure the time required for charging the battery. Is it 1 hour? 10? week? I'm curious!

Nihars2 (author)2016-04-08

or you can attach dynemo to can be stable & durable source of energy than this....

EdH18 (author)Nihars22016-05-17

Most modern mtb's atb's and roadrace bikes dont have mounts for a dynamo. nor is there a good surface for the dynamo to run against..

tho i cant imagine this being verry usefull either. i'll stick to my batterypack.

Unless someone can prove me wrong by actually testing it =)

chadeau (author)EdH182016-07-25

The alternate geneator has been done, an 'ible of its own . . . stepper motor with a larger diameter plastic wheel than the motor housing , attached to bike with a rigid metal strip to the thru bolt on rear wheel brake. The metal flex strip can also be clamped to rear seat stay , with plastic wheel centered over tread. The plastic wheel is centered on tire tread , unless tread is full knobby . . . and away you go. Definitely want to use regulator , these put out up to 30+ vdc , low amperage . . .

Bike Generator , Doug Costlow (not sure if the last name is a pun or not . . . )

jollyg (author)EdH182016-07-24

Have to agree with Nihars2, this is inefficient, but if you're going to make something out of what you have, what are you going to do?. I've never seen a bike with a dynamo mount either, the dynamo usually comes with it's own bracket to mount on the frame so it can be positioned correctly to run against the sidewall of the tyre. That said, who wants to add to the work they do when they're cycling? I'm off to work on some sort of energy recovery system that kicks in when you freewheel. :)

Ghostrider13 (author)jollyg2016-07-25

Now the free wheeling idea sounds promising. The dynamo adds work to the rider, the single fan doesn't. Now if there were several fans married to each other, that would work as long as each is producing power independently and all are moving power to the storage battery. This would create a wind tunnel effect with each fan turning easier because the one in front is helping spin the next fan behind it. Just a thought. I'd like to see if that works building off the original INS here.

cjameson (author)jollyg2016-07-24

Just want to point out that anytime you generate electricity from a kinetic system you increase the work that you need to do. The question is: how much electrical power do you want/need and how much are you willing to increase the work that YOU add to the system?

About This Instructable




Bio: Hi, I'm Tamas (Thomas), a 17 years old Hungarian guy. My hobby started more than 10 years ago. I learn electronics, physics, programming, IoT ... More »
More by Imetomi:DIY Cheap VR FPV System for Drones, Planes, CarsUltimate Intelligent Fully Automatic Drone Robot (w/ RPi, Arduino) Jedi Force Gestures Based Home Automation (with Smartwatch)
Add instructable to: