eBike batteries

[petehouk]

Hey everyone. Where are we hiding our eBike batteries? I bought a Hilltopper Sprinter conversion kit recently for my wife's Speedster. And I'm thinking about one for my Heavy Duti. But the battery packs are ugly!

What I really want is a custom battery pack that fits in the top of a cantilever frame (where a tank would go). I am sort of thinking about building a 36v pack in that shape from individual cells. Has anyone tried it?

Any other ideas for disguising a battery pack?

Thanks!

 

[axeman88]

I think Juicer had the coolest looking design. The batteries ( jumbos too, far more capacity than the little cells that most packs are built from) are arranged to look like the cylinders of a Vee engine. Hiding in plain sight, accessible, but gets that weight down nice and low.

I believe Kosynier packed their battery into the faux tank of their "investor bait prototypes", sort of like you suggest, but there's a LOT more space in a motorbike style frame than in the crescent moon of a cantilever. Their dummy cylinders are plastic moldings, or will be if they ever get them into production. After something like 5 years of waiting, their investors have got to be getting antsy, I would....

I've seen quite a few boardtrack racer designs that take this path. The drawback is that it puts that considerable weight up very high. This is the Michael Blast "Greaser" that Bike Berry sells

Moped styled bikes have a lot of options, ... they can put batteries in a faux tank, or on a rack over the rear wheel, or anywhere inside the frame space, which is mostly open. If you start out drawing the wheels, the seat and the crank, then the motor, and draw in the frame with batteries last, ... a lot of options open up. Like this long range setup, that carries it's battery weight nice and low:

Sondors built a custom triangular pack to fit the space, rather than glob a standard pack on somewhere:

I think I could do this all day. The field of e-bike design is rapidly expanding and lots of interesting new designs are popping up every week.

A quick and dirty way to get up and running fast, is to put the battery pack in a duffle bag on the rear rack. The weight is high and outside, but it's cheap and easy to swap or carry inside for recharging and theft safety. Personally, I'd give some considerable thought to function over form before committing to a laborious build.

 

[rgrrbt]

A quick and dirty way to get up and running fast, is to put the battery pack in a duffle bag on the rear rack.

Another, lower option, is to place the battery in a swing arm style motorcycle bag. Something like that would look good on a frame like Juicer's.

 

[Ulu]

I wonder if there is much attention paid to the temperature regulation on these battery packs?

I’m thinking that they will get hot under heavy operation or also during fast charging and so you might wanna system when you could regulate airflow to the batteries.

There might be an optimal temperature for them to operate at, But that optimal temperature may not always be the same temperature depending on the conditions of use, charge, etc.

I always wanted to build cylindrical battery packs into a heavy duty backbone tube frame, but I am afraid they would melt down. That led me to consider building that backbone even heavier, but with enough windows plasma cut into it to expose the batteries to airflow.

I live in the desert where it’s really hot during the summer day and often cold at night. Because temperature control is really important in all chemical reactions, I see the electric car people are taking huge interest in ventilation of the battery packs or liquid cooling of the battery packs.

That’s too bad because I thought the battery power was supposed to get us away from the corrosive problems of liquid cooling systems, But with hi-tech plastics, and the actual temperatures involved, that may not be a issue at all.

 

[Starnger]

Basically you want them as low as you can have, as it was mentioned already. It does make difference. So in my ebike project, despite of the cool looks of the filled tank area i've decided to put a battery on the bottom tube. Here how it looks on a render.

 

[Ulu]

I’m trying to imagine what it’s like to ride that bike standing on the pedals.

But with electricity it’s no problem.

I have been thinking about an experimental electric/pedal/2-stroke trike project for some time. But it’s going to be more of a utility vehicle than a sport vehicle. This transaxle has three speeds plus reverse and is all aluminum plus aluminum hubs.

It came out of my dad’s lawn tractor from the 70s. I put most of the miles on this so I know the history well. Since I won’t be pulling logs with it I can lighten the entire gear train, the hubs, & case enormously.

Anyhow this has been hiding under a tarp for 25 years. It might have a leaky seal or it might be that I was just sloppy putting the oil in it 30 years ago.