Mounting and security options for rectangular battery...

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cloudcover   10 mW

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Mounting and security options for rectangular battery...

Post by cloudcover » Oct 11 2018 3:50pm

Hello!

I have a Surly Big Dummy cargo bike with Xtracycle bags and a BMC rear hub motor. I recently bought a rectangular battery pack for it that's 324mm x 140mm x 80mm. I'm trying to figure out the best way to mount or house it and wanted to get ideas from the community.

For now, I've placed the battery pack in one of the inner compartments of my Xtracycle bags. The good thing about that is that it's very stealth and you can't really tell there's a battery there unless you're snooping. The main downside is that the weight is all on one side of the bike and it jiggles when I go over bumps or rough surfaces; a secondary downside is that cargo compartment is not available for other uses...though that's not a huge deal.

I was thinking maybe I would try to figure out a way to mount it on the seat stays that go from the bottom of the seat tube back to the rear wheel. Another option would be to put it in a trunk bag and mount that to the deck on the back of the bike.

I plan to use the bike quite a lot and would like to find a way to feel like the bike and battery are secure while I'm inside a restaurant having lunch, getting groceries, etc.

So that leaves me with a few questions:

1. any suggestions or advice on what may be the best way to mount / house the battery pack?

2. Has anyone fashioned a bracket of some sort for mounting a rectangular battery pack to their bike? I'm asking in case the best option for me is to mount it somehow on the seat stays going back to the rear wheel. and in that scenario I'm not sure what would be the best way for me to mount the battery pack.

3. I'm sure I'm not the first person to be concerned about how to secure a battery pack and was wondering what other folks do in that regard.

Thanks!

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amberwolf   100 GW

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Re: Mounting and security options for rectangular battery...

Post by amberwolf » Oct 11 2018 4:45pm

deleted since OP never came back to thread.
Last edited by amberwolf on Nov 15 2018 12:19am, edited 1 time in total.

2old   10 kW

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Re: Mounting and security options for rectangular battery...

Post by 2old » Oct 11 2018 11:55pm

+1 with a front rack since it helps balance the front/rear weight bias. This is the system that I employed on my DD rear hub conversion. Has worked perfectly with foam insulating the battery from road undulations. I'm ride a rigid bike since the roads and bike paths in my neck of the socal woods are well maintained. Of course you'll need to be creative to find a way to "lock" the battery which isn't something I worry about.

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Hwy89   1 kW

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Re: Mounting and security options for rectangular battery...

Post by Hwy89 » Oct 12 2018 12:08pm

Triangle bag works for me on my Big Dummy.
Photo taken under a bridge on the Nachez Trace parkway during a storm 2 weeks ago.
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wturber   100 kW

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Re: Mounting and security options for rectangular battery...

Post by wturber » Oct 12 2018 2:22pm

I use two plastic, waterproof, foam lined "equipment" cases. They were being sold as pistol cases at Frys Electronics. These particular cases are probably a bit small for your battery, but these things are available in many sizes. I use a small nut and bolt and a small "nusiance" padlock to keep the cases from being easily opened. But there is much more that could be done to make it even harder to open the cases. I've since mounted a milk crate on the rack, so it is even less obvious how to get into the cases in the current configuration.

viewtopic.php?f=2&t=90369&start=100#p1380508

viewtopic.php?f=2&t=90369&start=150#p1405129
Last edited by wturber on Oct 12 2018 8:51pm, edited 1 time in total.
"Commuter - DC Booster"
Iron Horse 3.0 hardtail - 48V / 1000W / 470rpm generic Chinese DD Hub motor (ebay)
8 x 36v 4.3ah 10s 2P battery packs - 1500W 30A DC Boost Converter delivers 54v and about 1000 watts peak
53T/42T Sakae Road cranks - 30mph+ on flats
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markz   100 GW

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Re: Mounting and security options for rectangular battery...

Post by markz » Oct 12 2018 8:45pm

I was using plastic ammo cases for awhile.
I made a box out of wood, used hose clamps.

Triangle bags are great!
The weight distro is great!

donn   100 W

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Re: Mounting and security options for rectangular battery...

Post by donn » Oct 14 2018 5:43pm

markz wrote:
Oct 12 2018 8:45pm
I made a box out of wood, used hose clamps.
Box of scrap wood, 3 big hose clamps, and ... bailing wire. (Green plastic coated, but basically bailing wire.)
Image

markz   100 GW

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Re: Mounting and security options for rectangular battery...

Post by markz » Oct 14 2018 6:16pm

donn wrote:
Oct 14 2018 5:43pm
Image
You forgot to blend the color in ;)

My batteries are always large and heavy because of the 1.6Ah 18650's
I am going to try the heat gun and PVC pipe method, I really dig the way they did that.
Much cheaper then a plastic ammo box or plexiglass.

Have you by chance seen Luna's battery shark box?
I dig the looks!
lunas battery.jpg

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