Alternative DIY off grid charging of battery pack (DIY also)

[boucaneer]

Now, although trying to study a good battery pack I can build, I would like to generate my own electricity with my tricycle using a permanent magnet motor or similar with my pedal/crank/wheel system whilst in the back and beyond to charge up my lithium ion or lithium polymer battery pack.

Does anyone know of a good system for doing this.

The A.C to D.C needs to be converted. I think I can keep the energy constant charging the permanent magnet motor if I concentrate. I'm just trying to find out the right Permanent magnet motor to research and at what volts, watts and amps to aim for.

If anybody can give me a few pointers or links to good sites then that would be fantastic.

I hope to find a good suitable power and system, I was even thinking about a thermogenerator recharging system but this might be simpler. As long as I have my tea/supper I can recharge my battery pack in the backwoods of the countryside, I hope.

Cheers.

 

[chvidgov.bc.ca]

Does anyone know of a good system for doing this.

No one knows of a good system for doing this.

First and Second Law of Thermodynamics rule.

 

[dogman dan]

There is too a good system. It involves recruiting about 20 young teenagers to do the pedaling, and then keeping them stoked up with sugary energy drinks. :wink:

Alas, due to the losses in the conversion, you have to pedal a hell of a long time to recharge a battery and then go someplace. Pedal enough to go there by pedal only about 10 times or more. It's pointless.

But ebikes used as a generator can be fun for less power hungry uses, like keeping the tunes rocking all day at a party where there are no plugs. But to be honest, I'd just fire up a small gas generator, and use a cord long enough to not hear it or smell it running.

 

[Eclectic]

What you want to do seems simple on the surface but unfortunately it is full of inefficiencies. Every time you convert energy from one form to another, some of that energy is lost (not really lost but you won’t have use of it anymore).

If I understand correctly, you want to convert food into motion. Use that motion to turn a crank. Use that crank to generate electricity. Use that electricity to charge a battery via an electrochemical reaction. Then use another electrochemical reaction to extract the electricity from the battery and turn that back into motion using an electric motor. Each one of these steps is inefficient and incurs some loss.

What you end up with is so much inefficiency is that you would have to work 2-3 as hard to accomplish the same motion that you would get by just pedaling the bike in the first place.

This is why so many here who dream of long range ebikeing in remote locations look at large solar panels, gas generators or just bigger batteries.

 

[boucaneer]

Ok, thanks for the heads up. I will try a look at thermal generation then and see what's about.

What's the voltage,watts amp's specification roughly to charge a typical battery pack?

Thanks.

 

[agniusm]

Your questions are stupid. What is a typical battery? For some 36v 10ah, for others 72v 20ah.
Amateur rider can produce 210w of energy for one hour continues. Do the math. Buy a solar panel and be done with it.

 

[LipoRider]

You're creating a generator from e-bike parts? Once the generator is engaged, you'll hardly be able to pedal. Even then, if you put in 'x' units of power, you'll only be able to get a fraction of that back for riding later.

This mobile pedal generation idea is impractical when it is powered by human power. Perhaps if we lived in a post-apocalyptic environment where there is no electricity anywhere but, somehow, lots of food available would the idea would become sorta practical. But you'd have to pedal for hours to get minutes of electrical ride time. At that point, you might as well put the generator on a stationary bike and have groups of people take individual turns "riding" it to charge up batteries for later use. Basically, you're converting food power (sugars, carbs) into current. Its basic thermodynamics. Food surprisingly has a lot of power -- just not all available in high rates unless you combust it freeing all the molecular energy bonds at once (steam engine power).

Maybe I'd like to have one of these bike generators in my bunker I'm planning to get me through the collapse of civilization! 8)

 

[Eclectic]

Everything I am about to say is over-simplified but here are the basics.

What's the voltage,watts amp's specification roughly to charge a typical battery pack?

It’s not the voltage of a typical battery. The voltage has to match the battery you are charging.

As far as watts, that depends. Again you are just converting energy from one form to another. If you are using 500 watts while riding for an hour, then you used 500 watt hours (Wh) of power. That means you need to replace those 500Wh (actually more than that because of losses). If you use a 100W charger, it will take 5 hours. At 250W, it will take 2 hours; 500W for 1 hour or 1000W for 0.5 hours.

While you are making those calculations, don’t forget that no charging system is going to be 100% efficient so make sure that you take inefficiencies in to account.

If you do come up with an effective method of “off-grid” charging, please let us know what you find. There are many here who are searching for the same thing.

 

[agniusm]

I think he meant that you must do some reading, studying trying things out, not just ask some stupid questions without even having basic knowledge how this and that work. In other words you can't count before you learn the math.
The man asks:
"What's the voltage,watts amp's specification roughly to charge a typical battery pack?"
you need to educate yourself what is volts, what is amps, watts, efficiency, do some ES browsing and such questions would not arise.
So he is right, no ONE can develop or build something asking basics. You need to educate yourself or go somewhere to get educated, then build one thing, another. With that will come knowledge and most likely that Numberonebikeslover didn't build hes controller just by asking questions like mosfet, resistor, capacitor.
Your mind opens up the more you do things, the more you read and do some dot connecting yourself. Learning how to open your mind sounds a bit silly.

 

[dogman dan]

Dang, I thought I had been harsh.

The thing you are looking for is the watt hour. If a typical battery is 36v 10 amp hours, then 36v x 10 ah is 360 watt hours.

Once you convert into watts, or watt hours, then you can make easy calculations. For example, a 36v 3 amps charger puts out about 108w (36x3). so that charger will run at least 3.6 hours to charge the 360 watt hour battery.

Real world stuff creeps in though, if you are pedaling at 100w (which is typical for a human), and your efficiency sucks, then you might be getting only 20 watts into a battery. That's 18 hours of pedaling to charge a battery that will take you about 20 miles max. You could walk it quicker. Or just pedal there in at most 2 hours.

 

[boucaneer]

Everything I am about to say is over-simplified but here are the basics.

What's the voltage,watts amp's specification roughly to charge a typical battery pack?

It’s not the voltage of a typical battery. The voltage has to match the battery you are charging.

As far as watts, that depends. Again you are just converting energy from one form to another. If you are using 500 watts while riding for an hour, then you used 500 watt hours (Wh) of power. That means you need to replace those 500Wh (actually more than that because of losses). If you use a 100W charger, it will take 5 hours. At 250W, it will take 2 hours; 500W for 1 hour or 1000W for 0.5 hours.

While you are making those calculations, don’t forget that no charging system is going to be 100% efficient so make sure that you take inefficiencies in to account.

If you do come up with an effective method of “off-grid” charging, please let us know what you find. There are many here who are searching for the same thing.

Thank you Eclectic, Dogman Dan and many others for your helpful answers, it certainly does help my learning.
Yes, my education is beginning, with the help of this good website. Using the knowledge and experience that the good members have will help guide me. Unfortunatly I recieved a head injury in Antwerpen 4 months ago and am currently recovering at home and studying when my health is well.

Just trying to find the right links of good sites is exhausting, but once found I seem to be able to read and learn from it if taken slowly and rest and think about the information. That the trouble with Traumatic Subarachnoid Heamorraging (S.A.H. ) it can take a longtime to heal.

I have a chance to leave London and a new start in India once I'm well enough to fly so trying to pick up the basics here from my recovery bed, it helps kill the boredom in this halfway house.

I will carry on learning about thermogeneration using fire/heat just like how my Powerpot V cooking pot charges up my phone and head torch just using a candle at 5watts, 1 amp, and try to make a bigger version of that. I was surprised to read that it was discovered or maybe rediscovered in 1826. Modern production company's are now installing it in their buildings now, I have been told.

The electricity system in the countryside of India is sometimes unreliable and we may be living off grid, so off grid thinking is the way forward for us with the Kerala Auxiliary Marine Service.

Yes, I now understand the inifeciency capacity and reasoning concerning pedal electricity generation. Putting coconut shell charcoal on the stove and charging up the battery while one sleeps does seem like a good idea, if possible.

There's also wind turbine generation too, but the patrol tricycle will have to be mobile so maybe a small boat wind generator may help. I will have to find out.

My specialist doctor suggested I keep my mind active and to use the Internet from my bed so thank you for your helpful answers and guidance.

My old captain once told me there are never stupid questions, only stupid answers, and your answers have been great and extremely helpful.

Well I shall eat my dinner and carry on learning about the possible solutions.
Thank gord for the Internet.

Thank you.

Alex.

 

[Punx0r]

Seriously look at solar panels IMO.

A trike is ideal as it is a vehicle that stays upright. So you can make a roof that will provide a large area for solar panels with minimum air resistance. In a hot country like India it would also provide useful shade from the sun.

Check out the size of 100 watt panels and see what you think. It provides power while you ride and when parked up during the day and could provide complete independence from mains electricity, generators or fuel for generating stoves.

 

[boucaneer]

Thanks Punx0r and Kiriakos,

Yes, I was thinking about solar panels on the tricycle, and I will certainly be very cautious and double and triple check and evaluate any future build with a profession or amature expert.

If I had a powerful enough solar panel run through a controller would putting the energy through a lead acid battery be a good way to charge the lithium battery's? Or is there a better system to charge the lithium battery packs by solar please?

I saw a video of an Australian chap doing it that way but don't know any facts or specs regarding his system.

So for example of we use the 100 watt solar panel running to a charge controller ( what size/make ) and then to an acid battery ( or other efficient/helpful battery ) and then charge the lithium battery pack with an icharger at 12 volts in a balanced charge. Would this seem a good way to do it?

I would personally like to cut out the acid battery and use a circuit or another piece of equipment if I can.
So solar at daytime and if needed a thermal charger by night.

This would be a way I would like.

 

[boucaneer]

Yes, I agree Kiriakos.

That seems to be the prepared realistic thinking.

I've just changed the name of this thread as it seems to be more suitable now.

Thank you.

 

[Eclectic]

A couple of threads about using solar panels for charging:

Solar Power Cruiser - Terratrike
http://endless-sphere.com/forums/viewtopic.php?t=62700

How to Solar Charge an Electric Bicycle
http://endless-sphere.com/forums/viewtopic.php?t=28436

solar powerd off road trike build log
http://endless-sphere.com/forums/viewtopic.php?t=46587

Solar panels can still be a challenge because of the cost and the area required to get enough wattage but they are currently probably the most practical method of using a LEV (Light Electric Vehicle) Off-Grid.

Don't forget, the "Search" function can be your friend

 

[Eclectic]

I also noticed that you mentioned a wind generator. If you plan on using the forward motion off an ebike to drive the generator, that will be inefficient. The energy used to drive the generator will be coming from your battery and that will end up generating a lot less electricity than you used to create it.

 

[boucaneer]

Thank you Eclectic, I shall check those links out, very much appreciated.

I will try to use the search engine, and very handy resource if used correctly. although its terribly boring here in the care home and the company leaves a bit to be desired. It helps to morale to discuss this project with fellow enthusiasts and it tends to give me momentum with the project. Maybe it is called Electric Vehicles Therapy. Lol

Thanks again, I will have a good read.

Cheers.

 

[dogman dan]

I think you will find solar the way to go. Not knocking thermo generation, but I just don't know what it would weigh to scale it up. I suspect the lightest modern solar panels will weigh less.

Don't completely ignore the idea of carrying a very small, very light gasoline generator if you cannot get to a working plug for days at a time. But truly tiny ones don't seem to exist. But with some study, it's possible to make one with a string trimmer motor. In effect, the small gas motor is your 20 teens with energy drinks pedaling for you. I would love to see one that put out just 300w of 110v AC, and weighed well under 15 pounds.

But for now, a larger battery, and supplement it with some solar input can be the lightest combination. The solar may be undersize, but it's role is more range extension rather than being able to actually completely recharge the pack every day. If you can cruise at 200 watts, then pedal up 100w, then a panel putting out 50w can double your batteries range. These are small numbers, but if you are in no hurry, a 100w panel ( on a clear day) can provide you with the same number of watthours as a 36v 20 ah battery. That's not bad. In a pinch, you could park for several days and get a full charge even with only a 100w panel. Unfortunately, carrying a panel much bigger gets difficult unless there are radical design changes to the vehicle. At some point, you end up with a solar car, including the long low cockroach shape.

If you will be towing a trailer, then a long low trailer can make a good surface for a larger solar panel.

 

[dnmun]

i find it is easier to just go knock on the door of the closest house and ask if you can plug in your charger to charge up enuff to get home. people i met always were totally willing to let me plug in. it is only guvment entities and official places like schools or libraries and supermarkets that get all hyped up. i even found an outdoor plug at the local walmart to use before i added more battery to my car. the manager of one supermarket left a note written on his business card telling me not to charge using their charging spot for the shopping cart return dolly electric mule. but that was just because one of the guys who drives the dolly felt threatened because it was something different and some people get upset when their world is a little different.

 

[dogman dan]

Once he gets better and goes to India, his problem might be a lot like the one I have here in New Mexico. It might be a loooong ways to the next plug.

Or when he gets there, it might not be the day they get a few hours of power in that town. In such a place, one starts to think a trike might be built with an electric front motor, plus a gas engine chain drive to the rear. Should be fairly easy to do on the trike rear ends. Not so much to charge while running, but to use as a back up when plugs can't be found, the sun isn't shining, or whatever.

Keep the dream alive dude. ES saved me while I was laid up in bed one summer with both collarbones broken. By the time I healed, I learned enough to help others.

 

[Eclectic]

I always thought that solarshift's vehicle (I hesitate to all it a bike or a trike) http://endless-sphere.com/forums/viewtopic.php?t=46587 was the closest thing to a DIY solar powered LEV I've seen. I think he was getting up to 600W from his panels. It might be tough to fit it on some roads though. Heck it looks like you could even hang a hammock under the solar panels at night so you could have a place to sleep if you were on the road.