I saw someone on ebay selling an electric mountain bike with the (Li-Ion) battery mounted in the front hub. It was probably a scam as all of his feedback was negative, so I don't want to contact him or anything...

But does anyone know where to buy those hub mounted batteries? I think I'd rather have my battery in the hub (assuming my motor is in the other hub). Probably help with the balance, and make the bike look more like a regular bike too.

Small folding bike, hub mounted motor, and hub mounted Li-Ion battery. That sounds about right to me.

The only system that comes to mind are the Tidal Force bikes. They ended up going out of business, but I heard that another company procured the rights to their technologies.

They used to make a folder too, which I know you're looking for.

As for now, I would think that coming up with your own battery wheel would probably be pretty difficult. Have you considered just getting a small front pannier? There are front racks you can get for most folders as well, and it would look *more* normal, with most of the gravity benefit and none of the effort.

Dang, so nobody out there sells a battery that can be put in a hub? You have to buy the whole bike?

I think batteries are what's really holding back the e-bike technology/development. You can buy a conversion kit anywhere that inculdes everything you need to convert a regular bike to an e-bike. You can also buy all the components seperately- but just try to find the batteries.

If batteries were as readily available as the motors and controllers, there would probably be top notch e-bikes for sale all over the place.

That's really too bad that the hub mounted batteries aren't readily available. That would have been the percfect solution to my needs.

Well, there are tons of batteries to choose from out there in all sorts of price ranges and chemistries, its not a case of fitting one inside a hub but rather of making/finding the hub to contain the battery itself. I don't know of any way to easily go about doing that, all I can suggest really is trying to watch ebay in case one of these tidal force systems or even one of the wheels comes up for bidding. Someone else might have a better suggestion.

I don't really know much about the Tidal Force bikes, but the battery hub was an interesting angle. Having the weight right on the axle would've made for very good handling.

If you're looking for batteries, I would suggest ebikes.ca personally, and most of the other members here know some pretty good sources.

Tidalfarce came up with the insane idea of a hub battery in the front wheel, needless to say Tidalfarce company went bellyup pretty fast. A hub motor is bad enough with all the weight in the rear wheel so they added a heavy NiMh battery in the front with only enough power to get somebody a couple miles before dying, so the suckers had to buy an auxiliary battery for plenty of bucks (from Tidalfarce of course) and stick it on the back rack to have any usable range at all.

I would be concerned about putting so much weight in the wheel. I know that with car designs, the better/faster cars spend oodles of $$$ to make the wheels as light as possible, using a variety of exotic alloys. Adding a battery to the wheel area itself seems to be somewhat counterproductive. What was mentioned earlier, however, makes some sense and that is to find a way to more evenly distribute the weight over the whole bicycle instead of putting it all on the back. If you want to find ways to conceal the batteries or not detract from the appearance for any other reason you can buy some ebikes that store the batteries inside the frame.

See, that's just it though- I don't want to buy a whole bike. I want to put my own together. I haven't seen a complete ebike yet that fits my needs. I've seen a few that were pretty close, but they were always way overpriced and under powered. I haven't seen one yet that has lots of power, easily folds to a compact size, is light enough to carry on a train, has the power to pull a bigger guy like me up a hill, and still manages to look normal when not folded.

The only thing stopping me from putting my own together at this point is the batteries. The only ones I can find are ugly blocks that need to be mounted.

If some ebikes out there store the batteries inside the frame, where can I buy those batteries?

I would think that with so many people selling hub motors that are already mounted on the rim, and turn key conversion kits, that there would be plenty of people selling batteries that are made for ebikes. But that's not really the case.

Sure, there are a few kits out there that consist of several batteries (that were made for cordless drills) all taped together to form a big, ugly, pack. But where are the companies that make/sell batteries made specifically for ebikes? Batteries that fit in the frame, and/or in the hubs?

It seems like with a frame and/or hub full of lithium you would have enough juice to be comparable to any other ebike out there.

Oil companies must own a lot of stock in the battery companies or something. Because in my opinion, batteries are the only thing holding ebikes back from going mainstream.

If it were as easy to get cosmetically appealing batteries as it is to get cosmetically appealing motors, then lots more people would be putting ebikes together. And lets face it, not too many people are going to be shelling out almost 2 grand to buy one that looks halfway decent. Especially when they could probably put the same thing together for under a grand of the batteries were for sale to the general public.

Sure, there are a few kits out there that consist of several batteries (that were made for cordless drills) all taped together to form a big, ugly, pack. But where are the companies that make/sell batteries made specifically for ebikes? Batteries that fit in the frame, and/or in the hubs?Someone mentioned earlier that batteryspace.com makes custom batteries (i.e. they use standard rechargeable cells, but wire and package them to your specs). If I remember correctly, there was a minimum order size involved in customizing though. Their web site might have more info on this.

--J

Lots of batteries can look decent. The trick is to put them in something convenient. I've tried mine out in a rack pack that goes on top of the rear rack, in a triangle frame bag, and in a pannier mounted on the front fork. Both the triangle bag and the front pannier are definetly my favourites. The MEC panniers i've got have a pocket on the outside perfect for holding the battery, a top pocket perfect for tire maintenance tools, and the main pocket is nice for carrying your stuff. Packed a carrying strap onto the top, and now its pretty much the perfect companion to the kit.

Well, if my battery wasn't giving out now. Time to look at some of the new chemistries like the LiFePO4.

Go to the "Atomic Zombie" website. They sell plans for an electric scooter design that places the battery pack about as low and central as is possible. They also sell plans for an ultra long range electric bicycle that also mounts the batteries centrally. I agree that the weight of a battery pack over, near or inside the front hub might create some interesting handling effects but I for one like the elegance of the design. Don't blame TidalForce for the fact that efficient, light batteries were/are not available so the true genius of their design wasn't fully realized! When and if such batteries do arrive do you want to bet that the TF battery placement won't return?

H

Oil companies must own a lot of stock in the battery companies or something. Because in my opinion, batteries are the only thing holding ebikes back from going mainstream.

Batteries are the only thing holding back ALL electric vehicles from going mainstream. Motors, controllers and everything else is already in place.

decent lifepo4 batteries are available - they require a bit of maintenance (for some brands) to keep them balanced. im using lifepo4 and they're great. i get a large enough range to go to work at high speed. its faster than taking the car.

decent lifepo4 batteries are available - they require a bit of maintenance (for some brands) to keep them balanced. im using lifepo4 and they're great. i get a large enough range to go to work at high speed. its faster than taking the car.

I'm poor, so I bought a little 24V 10Ah LiFePO4 pack for my bike. The bike trip to work will definitely be slower than the car, but that's fine by me. LiFe technology is great.

Of course, it's not on par with gasoline in terms of being able to get cheap storage for 200 miles of range (really, how much can a gas tank cost?) but it is a pretty darn good deal.

Why should gasoline still be held up as the gold standard for energy storage? Its sad that just because LiFe is the current state of the art in battery technology that we have to be impressed with it. Does anyone know the energy storage capacity of the batteries in the Lunar Rover that the Apollo missions took to the moon 40 years ago? Even if it was only equivalent to LiFe, its a crying shame that we haven't managed to improve capacity, weight and/or cost in two generations.

H

Yes, you can buy batteries now in any shape you want. The trick is...most people do not have the tools and $$ to fabricate their own bike with a tube that is designed to hold the battery. The suggestions I have heard for using panniers, etc will be about the best you will find. It is not likely that you will end up with something really slick looking but it will be practical and, with a little effort can be neat.

Where can you buy batteries in any shape? I have been searching for days and haven;t had any success. If anyone has a source, please post it.

Why should gasoline still be held up as the gold standard for energy storage? Its sad that just because LiFe is the current state of the art in battery technology that we have to be impressed with it. Does anyone know the energy storage capacity of the batteries in the Lunar Rover that the Apollo missions took to the moon 40 years ago? Even if it was only equivalent to LiFe, its a crying shame that we haven't managed to improve capacity, weight and/or cost in two generations.

H

Here you go:
http://en.wikipedia.org/wiki/Silver-oxide_battery

Silver-zinc batteries were used. At least in the projects I know of, the Grumman Apollo modules being an example.

These batteries provided performance fairly close to what lithium does, although they had complications and drawbacks. Granted, for its time these were the best, although comparatively lithium chemistries now provide better performance in a much cheaper package, and new lithium revisions have become quite safe as well.

Oh, the wiki article is a little opinionated about its "demise"

Improvements have been made recently, one company called "ZPower" has apparently improved the lifespan and reliability of the battery. ZPower claims that their product currently has 30% more wh/l, and that their batteries are only becoming more efficient as time goes on. Still, doesn't help the cost of silver these days, which would be prohibitively high for most applications.

http://electronicdesign.com/Articles/Index.cfm?AD=1&ArticleID=17084

Are these batteries dead? Maybe, maybe not. Hey, i'm not a technology analyst!

And if I was, my job would be to tell you whatever you wanted to hear anyways :)