Secure battery case?

[veloman]

I really want to finish my ebike off with a quality secure battery case. It needs to prevent theft, and hold the battery securely inside the frame triangle. I would like to have it bolted to the bottle cage mounts. Then perhaps a lid that locks.

What aluminum cases are out there that are about 3.5" x 11" x 5.5" ? I don't want some bulky tackle box, it won't fit. Plastic won't be as secure, I really think I need aluminum. Design it for a few hours outside a bar in a busy / low crime part of the city at night (not a dark alleyway). I've left it completely bare, just held on to my frame by packaging tape, and obviously I've been lucky. I've heard of wheels being stolen off bikes in this area though.


I don't have much if any custom fab ability. Well... now that I think of it, I could get some sheet metal from Home Depot and fold it into the proper shape.... but it won't be as strong as a manufactured item.

Just a tab too skinny:
http://www.toolboxesdirect.com/tool-boxes/metal-tool-boxes/excel11inchtoolbox.cfm

 

[johnamon]

The most secure thing to do is remove the battery when you get off the bike. I put my battery under my desk when I get to work. When I stop off past the grocery shop on the way home I remove the battery and throw it into my rucksack. I also use a good lock between my powered front wheel, the bike frame and something solid nearby. The standard issue rear wheel is about the most they could steal in this locked up state.

I figure that most bike theives are opportunistic ars* holes. If I took it upon myself to steal a bike - which had the battery removed - I'd probably dump it at the next opportunity given the effort involved to shift that weight of ebike!

 

[Ziggurat]

In another thread I mentioned a lockable safebox I used in the back panniers (http://endless-sphere.com/forums/viewtopic.php?f=2&t=27624#p400295). It's steel, not aluminum, but it's still pretty light.

Since then I decided to move it into the triangle, using the bottle holder mounts as you said, and also a brace at the back corner with one of those back reflector holders that can be tilted and tightened into position. Just drilled holes for wire entries, the bottle-mount bolts, and the corner brace bolt.

Not quite the dimensions you asked for -- it's about 3" x 9.75" x 7" (needs a little more than 7" in the triangle due to gap at the bottle mount), but if that won't work for you there are probably other similar safeboxes with slightly different dimensions.

 

[veloman]

Removing and taking the battery is not a feasible option if you are going out for some drinks.

I've been leaving my completely vulnerable battery on my bike at many grocery stores (good areas of town) for up to 30 minutes at a time. I do worry a little, but have been lucky. I am looking to make it secure enough that it would require tools to remove - like a saw or some serious bashing. The odds of a theif going through all that work are so slim around here. Normally, bike theft is due to a bike being locked with a thin cable, or no lock at all. It is was NYC, it would be very different.

Do theives know that ebike batteries are worth anything? Even if they do, they must know it's not something you can easily sell, as there is no local market for them. And even if there was, used batteries have quite a low value to begin with. It's not a like a nice mid level mtn bike sitting at the bike rack with a thin cable on it.

I am moving to a new place, and that may require me removing the battery for easy charging in my room, if my room is on the 2nd floor of a house or such.

I ended up getting one of those plastic file holders at office max for $6 - the perfect width and length, will trim the rest and add a top. I can bolt through the hard plastic on the bottom, add more hose clamps and stabilizing attachment for the seat tube. Then I can simply slide the batter in and out the top, which I can try to design a locking top for, which will be the tricky part. Should add 2lbs at the most. I don't want to add 5+lbs to an already too heavy bike.

Still looking for a similar safebox as mentioned above. Needs to be 11" long though.

 

[Kiwi]

I designed (above) these to fit ping batteries, aluminium and bolt in place, they also house the controller 6fet, ignition key and fuse.
I have sold all I had made, and are working on a new case to hold 300mm 12" long ping batts, eg 36v 20ah or 48v15ah, and smaller of course. I wont be making room for the controller in these, but hope to get the ignition and space for a 12v dc converter.
There is likley to be studs or insert nuts so you can screw your controller to the outside of the case.

Unfortunatly, I am stretched with many projects, so could be the end of the year before these are fabricated.

Could be good for lipo too. Inside battery area 110mm x 150mm x 300mm.

 

[dogman dan]

That's a fairly tough dimension to find. You might hunt some trift stores for vintage steel file boxes. Most of the ones I've gathered are more like 4" instead of 5.5" Other stuff that is that wide is just like the tackle box. There is a small tool box at harbor freight that may be close.
Possibly too wide to fit though.
http://www.harborfreight.com/hand-tools/tool-boxes/11-1-2-half-inch-x-7-1-2-half-inch-x-4-1-2-half-inch-aluminum-case-36870.html

 

[veloman]

I was on the hunt at home depot for materials. I ran into the mailbox section and found something similar to this, but it was too thin. This one is perfect, other than being 4 inches too long (which isn't a problem on my bike).

I'll just say that my bike was it's own address where mail gets delivered :lol:

http://www.lowes.com/ProductDisplay?partNumber=99209-1622-LTHHB0000&langId=-1&storeId=10151&productId=3048651&catalogId=10051&cmRelshp=req&rel=nofollow&cId=PDIO1