Battery Connections.

tomtag

Finding my (electric) wheels
Feb 11, 2019
22
0
Morning All, On my conversion kit on an MTB I have purchased a battery separately from the conversion kit. The way it is installed I have ended up with 2 connection points in the controller to battery wire, one at the end of the controller tail & one at the end of the battery tail with a length of wire in between. I have manually spliced these connections & covered with heatshrink. This seems to be working fine at the moment (no heat etc.) but doesn't seem like the best solution going forwards. There is a 2 pin screwed connection/plug at the battery, which came with the mating plug & a 6" length of wire. In hindsight, what I should have done is take the soldered tails off the battery plug & connect to the original kit wire, which would remove 1 of the 2 connections. I was wondering what would be the ideal solution here & would welcome any input.
I assume a permanent spliced/soldered connection is better (& neater) than a plug if done properly, especially if I have a plug at the battery anyway. Does anyone have any recommendation of the best way to permanently join 2 power wires on an ebike? Thanks.
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
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Nealh

Esteemed Pedelecer
Aug 7, 2014
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More expense !!!!
 

BudgetBodger

Just Joined
May 26, 2020
1
0
Long time lurker, first time poster. If you have no need to disconnect the battery holder assembly from the controller, then solder the cable together and heat shrink. If you do need to remove the battery holder semi-regularly because you are still tinkering, then my solution is to use Wago 221 connectors. They make good contact on cabling from 0.5 - 6mm^2 and are rated to 32A 440V (so even a bonkers 3000W mid-drive will be fine). And if you get 5 way blocks, they can be used as a break out point for lights etc.
(edit - Link to screwfix for ease: https://www.screwfix.com/p/wago-5-way-lever-connector-221-series-32a-pack-of-25/5201r )
 

tomtag

Finding my (electric) wheels
Feb 11, 2019
22
0
Hi Budgetbodger, apologies for the slow reply, many thanks for your input. I have a screwed plug connection into the battery; so no other connections will need to be broken if I want to remove the battery or controller. At present I have ended up with 2 joints on the battery to controller cable, both spliced with no solder, I'm torn between leaving as I have no issue or doing a better job to prevent getting any problems. (didn't have a solder iron at the time).
Nealh & vfr400 I have attached some photos of the cable I was referring to. The question really was what the best method to put a permanent joint n the cable & if splicing, is solder an absolute requirement & is there a specific method for splicing? - I saw the heat shrink with solder type connectors & wondered if this would be best?
https://www.amazon.co.uk/Connectors-Sopoby-Electrical-Waterproof-Assorted/dp/B07V3QMR3T/ref=asc_df_B07V3QMR3T/?tag=googshopuk-21&linkCode=df0&hvadid=232000808334&hvpos=&hvnetw=g&hvrand=736937155945314993&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=1007064&hvtargid=pla-833740576234&psc=1
 

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vfr400

Esteemed Pedelecer
Jun 12, 2011
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I'm not sure I understand what you're saying. It sounds like you don't want to solder anything. Have you just twisted the wires together to join them, then put heatshrink over the top. if so, that won't last very long. Copper oxidises in air. Eventually the surface contact between the individual strands will break down. You should solder them. The tin/lead solder mix doesn't oxidise, so it protects the joint for ever.

Soldering is not difficult. A lot of people think they can't solder because they use the wrong technique. I used to teach 11 year old kids to solder. every one of them was successful after some basic instruction. If you want to have a go, buy a soldering iron and some tin/lead solder, like this one:

and some 60/40 tin/lead solder:

When you have it, let us know and I'll give you an exact instruction that will make you always solder successfully.
 

tomtag

Finding my (electric) wheels
Feb 11, 2019
22
0
I am happy to solder the connections, but at the time of installation didn't have the equipment so yes twisted connections. Also wasn't sure how much worse than a properly soldered connection this was; which you have now answered so I will look to rectify. I will get hold of an iron and solder, many thanks for the offer of advice on the best method. Those solder-seal connectors look a bit quicker and simpler, do you have any experience of them and if they are as good as the normal method?
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
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Those solder-seal connectors look a bit quicker and simpler, do you have any experience of them and if they are as good as the normal method?
They need to be rated and be able to handle the max current the controller ask's for, no use if they are only 5 or 6a rated.