Laminated Carbon Fiber Battery Enclosure

hillzofvalp

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Somewhere over the rainbow, Canada
I've seen some examples of fiberglass enclosures, but I don't like how potent the process can be.

http://www.carbonmods.com

I thought of ordering $150-200 of supplies from these guys this summer and making a triangle-mounted enclosure for my M1 pack I'm building soon. It looks fairly painless. I would hope to use the method of modeling the enclosure with stiff foam first and then laminating it. I would also like to incorporate an idea I brought up on another thread which was the inclusion of a zipper (heavy-duty) into the carbon fiber weaving.

Also, what about laminating the carbon fiber around the bike tubing as well as the Styrofoam model so as to create a permanent or semi-permanent mounting solution with cleaner lines?

What do you guys think?
 
You can avoid CF and just use layers of glass cloth to keep costs down. Carbon fiber is conductive as well. There is no difference in the process. Epoxy is used instead of polyester, but is just as toxic. Use appropriate precautions.

CF also has more danger to your lungs when cutting or sanding vs fiberglass, but both process should use a mask.
 
Yep. Fiberglass let's you make a pack, and glass right around it, mount busses and terminals right in it etc. With carbon, you gotta fully insulate the pack, busses, connections, etc, and then carbon over it. Also, carbon fiber slivers and dust are just that much worse than fiberglass.
 
Good information. Thanks.

I chose carbon fiber not only for its appearance, but for strength. For example, I would estimate needing $50 of material (2 meters squared) for the whole thing, and would use one layer over all with reinforcements from scraps put around the sides. The other supplies would be $100 I'm estimating.

What is the total cost of dealing with fiberglass? minus $50?
 
I can get a qt of laminating epoxy for $25 and enough glass for less than that.
 
Regardless of using either type, avoid sharp corners in the design if possible. However, if a sharp corner is useful in a certain place, consider aluminum angle as an embedded reinforcement with multiple holes to allow adequate bonding.

A triangle enclosure is very desireable. Try it as a battery mount first, but even if you decide to mount the batteries elsewhere for some reason, the triangle box can hold gloves, cable/lock, wrenches, etc.

DIY all carbon fiber knife builds, with step-by-step pics
http://endless-sphere.com/forums/viewtopic.php?f=1&t=18906

DIY custom frames, home carbon-fiber method simplified
http://endless-sphere.com/forums/viewtopic.php?f=2&t=10906

Fiberglass battery case
http://endless-sphere.com/forums/viewtopic.php?f=2&t=24382
 
West systems epoxy resin is non toxic you can do layups in your bedroom and sleep right beside it with no fumes what so ever!
I used a couple other so called epoxy resins and they were terably stinky and got everyone in the shop hi as a kite!

My battery boxes are CF!
Check out my ysr build page and I will post up some of the step by step stuff I did for all the fiberglass and CF I am doing on it.
I only have one mold left to build!
Im trying to have all the CF layed up by next weeked!!!!
 
Arlo1 said:
My battery boxes are CF!
Check out my ysr build page and I will post up some of the step by step stuff I did for all the fiberglass and CF I am doing on it.
I only have one mold left to build!
Im trying to have all the CF layed up by next weeked!!!!

Yeah definitely post how you did it. I actually have access to a cnc shop so I just make the molds there (if I can't just laminate a piece of foam with acceptable results). How many layers are necessary for a 14s5p pack of a123 m1 cells, do you think (~12 pounds + controller)?

Is this a good kit?
http://www.jamestowndistributors.com/userportal/show_product.do?pid=3842&BASE
 
hillzofvalp said:
Arlo1 said:
My battery boxes are CF!
Check out my ysr build page and I will post up some of the step by step stuff I did for all the fiberglass and CF I am doing on it.
I only have one mold left to build!
Im trying to have all the CF layed up by next weeked!!!!

Yeah definitely post how you did it. I actually have access to a cnc shop so I just make the molds there (if I can't just laminate a piece of foam with acceptable results). How many layers are necessary for a 14s5p pack of a123 m1 cells, do you think (~12 pounds + controller)?
Depends on the weive and the thickness of the individual strands but ~4 layers of CF gets pretty strong 6 would be max with the 2x2 twill I use, with just a wet layup.
If you want to get crazy you can vacume bag your parts it will suck out the air and the extra resin making it lighter and stronger.
I vacume bag all parts were weight and stregth is a concern!
 
Do you have any leftover?! ;) (poor college student alert)

And what do you think about making the "panels" to the battery box and connecting them to separate, permanent mounts wrapped around the bike frame. Kinda like a spider web. I guess the panels could be fastened with more carbon fiber.

I want to use the bare minimum of materials so as to minimize cost.
 
hillzofvalp said:
Do you have any leftover?! ;) (poor college student alert)

And what do you think about making the "panels" to the battery box and connecting them to separate, permanent mounts wrapped around the bike frame. Kinda like a spider web. I guess the panels could be fastened with more carbon fiber.

I want to use the bare minimum of materials so as to minimize cost.
If you want to keep cost down stay away from carbon fiber. And the west systems epoxy resin is more expensive then polyester resin.
Where are you located??? If I had to guess I proly have $60-$90 worth of shop supplies into my battery boxes!
 
hillzofvalp,

I've been considering a battery box along the same lines as you. For cheaper materials try http://www.easycomposites.co.uk they're the sister site to carbonmods but a little cheaper!

I'm interested to see how you get on. Its not so much the box build that is the difficult part its the mounting to the frame I'm still thinking about.
 
Oh an one thing I did to be able to suspent my batteries inside my frame was...
First a cleaned and polished a spot on the frame I wanted to mount to then I put a coating of pva release compound on the tube then I layed up 2-3 layers hanging over that spot on the frame and when it cured I poped it off and trimmed it to ~1/2 tube shape to be able to clip-on to the frame again. Then I placed my battery box where I wanted it and cliped the 1/2 tube to the frame and layde up a couple layers on each side going from the box to the 1/2 tube.
Once this was dry I drilled a hole in the flat section between the tube and the box and slid a reuasable Zip tie through and that wraps all the way around the tube to hold it from poping off and still let me get my batteries off my bike quick!
I will put up more pictures later!
 

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hillzofvalp said:
could I get away with using carbon fiber for only the outermost layer and using glass cloth to reinforce it?
Yup lots of people use fiberglass weive to make up the bulk and just use a layer or two of CF.

If you want it for looks you want at least 2 layers of CF on the outside because sometimes you can see inbetween the weives in spots and it will show the color fomr next layer under it.
 
Basicly if you can think of it you can do it. Epoxy will hold anything together well almost!
Here is my build http://endless-sphere.com/forums/viewtopic.php?f=10&t=18183&p=398620#p398620

And some other things around my shop made from CF
 

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HMM....

nice wheelies. I would like to pursue making an A123 M1 pack that fits beneath the bottom bracket and downtube... kinda like this:
5690249013_44e55738c8_z.jpg
 
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