Charging your battery with a bicycle electric generator

[tzetzumbal]

hello

I am taking my e-bike on a bike tour. I have 2 batteries. I wanted to know if there is a way of charging the battery I am not using with a bicycle electricity generator. If anyone has some information on this I would appreciate it very much.

Thank you!

 

[Gregory]

If you mean using the motor to turn the rear wheel and a generator hub on the front then no. Your motor uses more power to turn the generator and you get a net loss of energy.

For more info try these threads (and many others).
https://www.endless-sphere.com/forums/viewtopic.php?f=3&t=29041
https://www.endless-sphere.com/forums/viewtopic.php?f=1&t=53941

And one guy who wanted to pedal charge his battery, but due to losses he'd be better ditching the motor and just pedalling. https://www.endless-sphere.com/forums/viewtopic.php?f=14&t=64745

 

[dogman dan]

You could travel for a time, then stop and rig your bike to be a generator, then pedal to charge the battery.

But because of wattage losses along the way through the system, it would be much less effort to just tour without a motor. You pedal 100w, then 15 watts gets into your battery. No motor you pedal 100w, and 99 w gets to the tire.

Look for threads from folks that are currently using the newer, very lightweight solar panels on their bikes. 50-100w of panel can be carried now that the panels got lighter, and even just a few watts more from sun can greatly extend range.

Plan to travel slow, and your batteries will go farther as well. Adjust your speed to match the distance you need to the next chance to charge.

The other approach that can work is to carry a gas generator. But the lightest ones are at least 30-40 pounds. Better to just carry that weight in the form of more battery IMO, or carry much lighter solar panel. I do take my bikes to places where there are no plugs, by car. Then set up a camp and do a day or two of riding using the gas to charge. But carrying the generator on the bike is too much weight for me.

 

[arkmundi]

Its an interesting question that I and lots of other ES members have periodically looked into. Not so much to have it attached to an eBike while in motion, but while in camp on long distance touring. I'm more inclined and am currently researching light weight solar PV for that, but have considered http://pedalpowergenerator.com/diy-byo/

 

[dogman dan]

Bleah. Pedal all day, then pedal some more in camp? No thanks. For camp power on a bike tour, I carry a tiny 12v 10 ah lifepo4 battery. It will light my tent and keep my ipod and phone charged for two days easy. Recharge it when I charge the bike.

For a car/ bike tour, the gas generator is great. If I tow a trailer, I can charge bikes while driving to the next riding spot. Cheating to bring the car, but it can be nice to go ride a different road, without a 300 mile ride to get there. The car/ bike method allowed me to ride from El Paso to Santa Fe, riding each road out and back on a string of day or weekend trips over a 3 year span.

 

[crea2k]

The only way you will charge the battery without expending more energy than you are putting in is via a solar panel on your back, bag etc. Using anything bike connected to charge it like a dynamo on the wheel etc is only going to expend more energy out of the battery you are using than you are putting into the new battery.

 

[d8veh]

I spent a lot of time looking into micro-generators thst are powered by a small IC R/C motor, but it all seemed far too complicated, but then I had another thought. You could mount the model aeroplane engine on a hinged mount with a friction drive to the wheel. At the end of your ride, you put the bike on a stand and fire up the motor. After a few hours, your battery would be charged back up by the regen. You'd need a good silencer if you want to use it in a camp site though! The motor and fuel would add 2 to 3 kg.

 

[Stone Meadow]

hello

I am taking my e-bike on a bike tour. I have 2 batteries. I wanted to know if there is a way of charging the battery I am not using with a bicycle electricity generator. If anyone has some information on this I would appreciate it very much.

Thank you!

As others have mentioned, you could go solar, like this 75 watt panel.

NOT like this one, though...

 

[Punx0r]

I spent a lot of time looking into micro-generators thst are powered by a small IC R/C motor... After a few hours, your battery would be charged back up by the regen. You'd need a good silencer if you want to use it in a camp site though! The motor and fuel would add 2 to 3 kg.

I wonder how many hours those little engines can run for before needing a rebuild or replacement?

 

[d8veh]

I was thinking of something like an OS 52 four stroke. They're pretty reliable and can give over 500w without pressing them hard.

 

[Punx0r]

Spec says 434g weight and 0.9bhp @ 12,000rpm.

I can't find any indication of expected service life, though.

It's a novel idea, but I have a feeling that using it would be a thoroughly hateful experience.

 

[crea2k]

I spent a lot of time looking into micro-generators thst are powered by a small IC R/C motor, but it all seemed far too complicated, but then I had another thought. You could mount the model aeroplane engine on a hinged mount with a friction drive to the wheel. At the end of your ride, you put the bike on a stand and fire up the motor. After a few hours, your battery would be charged back up by the regen. You'd need a good silencer if you want to use it in a camp site though! The motor and fuel would add 2 to 3 kg.

If you are staying in a campsite why dont you just get a pitch with an electric hook up and charge it up like that ?, all you need is a caravan power plug with a 13 amp plug socket on it .

 

[d8veh]

If you are staying in a campsite why dont you just get a pitch with an electric hook up and charge it up like that ?, all you need is a caravan power plug with a 13 amp plug socket on it .

That's what I used to do, but then I discovered that you can put duct tape around your spokes to turn your wheel into a windmill rotor. Now I just park with the wheel in the air, and when I wake up in the morning, the battery's charged and ready to go. The only problem is that whenever I ride at more than 20 mph, the bike goes sideways.

 

[crea2k]

Thats got to be some serious wind to turn a hub motor lol, I like the idea

 

[Gregory]

lol, I assume that was a joke!

 

[d8veh]

lol, I assume that was a joke!

Normally, when you assume something, you make an ass out of u and me, but in this case, you're correct.

You'd be surprised at how many times people suggest a dynamo on the front wheel to charge the battery while they're using the motor on the back wheel. When I was about 11 years old, I built a model boat with a big funnel on the top. I figured that all I needed to to was give it a good push to start it and then the funnel would compress the air into a jet that would speed it across the pond. No matter how hard I pushed, it stopped dead as soon as I let go. I was very disappointed because it took a lot of time to build it.

 

[izeman]

@d8veh: you gave yourself the answer why it didn't work. It's not because a perpetuum mobile doesn't exist! It's because you were a small and weak 11 year old boy. You should try it now being a strong and grown up man! You for sure can push it much harder now.

 

[Stone Meadow]

You'd be surprised at how many times people suggest a dynamo on the front wheel to charge the battery while they're using the motor on the back wheel. When I was about 11 years old, I built a model boat with a big funnel on the top. I figured that all I needed to to was give it a good push to start it and then the funnel would compress the air into a jet that would speed it across the pond. No matter how hard I pushed, it stopped dead as soon as I let go. I was very disappointed because it took a lot of time to build it.

Don't feel bad. When I was 4 or 5 years old I asked my dad how the radio in the car worked, because I didn't see an chord going back to the house to be plugged in. :lol:

 

[tzetzumbal]

If you are staying in a campsite why dont you just get a pitch with an electric hook up and charge it up like that ?, all you need is a caravan power plug with a 13 amp plug socket on it .

That's what I used to do, but then I discovered that you can put duct tape around your spokes to turn your wheel into a windmill rotor. Now I just park with the wheel in the air, and when I wake up in the morning, the battery's charged and ready to go. The only problem is that whenever I ride at more than 20 mph, the bike goes sideways.

Iç

 

[crea2k]

I see ?

 

[d8veh]

Just to make it clear, my post was a joke.

 

[dogman dan]

There are tiny wind generators, and places where it blows that much. But the best solution I've seen is the solar panel, combined with very slow travel allowing half the power to come from legs, and the other half from the panel.

If you don't mind slow, 150w will do er on the flat.

 

[crea2k]

You could do it with a peltier and a camp fire, this would be by far the easiest solution, this one outputs a max of 200watts, but the more you have the more current it would output, you'd have to put it through some kind of buck converter though to step the voltage up, unless you can put some of them in series, but you'd want some caps on the output to smooth the current out.
https://www.youtube.com/watch?v=2gVN-pKtQs0

 

[crea2k]

Interesting one https://www.youtube.com/watch?v=7_IeODun_Qo

 

[knighty]

hello
I am taking my e-bike on a bike tour. I have 2 batteries. I wanted to know if there is a way of charging the battery I am not using with a bicycle electricity generator. If anyone has some information on this I would appreciate it very much.
Thank you!

connecting both batteries to the bike at the same time, and using regen breaks is about the best system you'll get