Most waterproof connection method between battery and motor? (TSDZ2)

DarkerSide

Finding my (electric) wheels
Mar 3, 2020
11
2
Hi folks

I've almost finished converting by touring bike to use a Tongsheng TSDZ2 kit from Woosh, which generally has been an excellent kit and straightforward to use. The one bit that's concerning me is the connection between the battery mount and the motor.

(I've written up a post on the build here if anyone's killing time during isolation, but the key photo is at the end.)

The kit comes with some chunky bullet connectors, to the point that once I'd given them a wrap in insulation tape, I couldn't get any of my heat shrink sizes over the top. I could redo the connectors to stagger their position, which would make it easier to get a wrap over, but I'm wondering whether a better solution would be some kind of magical tiny, water resistant junction box.

Does such a thing exist?

This will be an all-weather commuter in western Scotland, so it may get slightly damp on occasion... :)

Cheers

Rob

 

sjpt

Esteemed Pedelecer
Jun 8, 2018
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One problem with insulation tape is that if not applied very carefully if can hold water longer than an unwrapped connector would, and it won't necessarily be that obvious. Would heat shrink fit over the connection without the insulation tape?
 

DarkerSide

Finding my (electric) wheels
Mar 3, 2020
11
2
One problem with insulation tape is that if not applied very carefully if can hold water longer than an unwrapped connector would, and it won't necessarily be that obvious. Would heat shrink fit over the connection without the insulation tape?
Not as a pair, but thinking about this that's probably not what you're suggesting. Shrink each connection individually and not bother with one over the pair?

Part of my concern is I've never had good results with heat shrink (previously used it a lot with dynamo lighting systems). Wondering if I do need some kind of hot air blower rather than a lighter...

 

DarkerSide

Finding my (electric) wheels
Mar 3, 2020
11
2
I don't, but if there's ever a time to learn new skills it's when you're stuck in a house... If soldering is the best choice, can give that a go.
 

sjpt

Esteemed Pedelecer
Jun 8, 2018
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Not as a pair, but thinking about this that's probably not what you're suggesting. Shrink each connection individually and not bother with one over the pair?

Part of my concern is I've never had good results with heat shrink (previously used it a lot with dynamo lighting systems). Wondering if I do need some kind of hot air blower rather than a lighter...

I hadn't noticed from the first picture that there were two separate connectors rather than a twin. Heat shrink on each separately will considerably reduce the major risk of water connection between the red and black, or either to the frame..

wheeliepete's soldering suggestion above looks good as well; could be awkward if there isn't enough cable length conveniently to stagger the joints. Also more awkward to undo and redo if needed.

I've never used heat shrink but I can see its benefits. My soldering is pretty bad, but this would be one of the simplest soldering jobs if there is enough cable. Make sure there is a strong mechanical connection by twisting the bared wires together before soldering; though that will need a little more free cable length.
 

DarkerSide

Finding my (electric) wheels
Mar 3, 2020
11
2
Thanks for the thoughts, folks. I'm going to try heat-shrinking the individual connectors for now, although I've ordered a cheap mini heat gun to try and get a better result. Although I'm sure soldering would give a better end result, I'm still looking in to running a connection off the battery for lights and a horn, so I don't want to do anything too permanent (and the length of free cable from the battery mount is on the short side...).

Besides, it doesn't look like I'll be doing any commuting on it for a few months at the moment...
 

Danidl

Esteemed Pedelecer
Sep 29, 2016
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There is a product called self amalgamation tape.. Lidl and Aldi occasionally have it, as well as Amazon and electrical and TV shops. It goes on as a slightly sticky rubbery tape..you remove a plastic interleaf. But then the layers meld together making a semihard protective layer. .. totally weatherproof. Its only drawback is you need a Stanley knife if you ever need to access the joint.
For the purposes it is better than heat shrink.
 

DouglasXK

Pedelecer
Oct 9, 2016
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Any of the suggestions will work but your bigger problem is the gap where the power cables exit the halon case. Moisture up there can be lethal. Fill it with RTV silicon.
 

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