Ebike Battery connection melting

[Dominator]

Hi there, my name is Dom. I live in New Zealand and a few years ago bought an ebike to commute to work. The commute is about 30km and on the ebike it takes about 50 minutes using full power. The bike is a Magnum Metro.
Recently I've noticed the power faltering at times. Now it's getting more frequent. I took it to my local bike shop and they just said "oh you need a battery specialist up in Auckland to look at it. Might need a new battery or even a new battery management system".
I looked at the battery connectors recently as at times the battery doesn't detach easily from the bike, and I realised that the connectors are melting at one of the pins. I'm assuming this is the cause of the power dropping out while I'm riding.
I was thinking about replacing the connectors first and have found them online but I'm not confident I can replace them well (it's not clear if I'd need to solder them etc or if they will just connect via plugs). I tried to lever out the melted plastic on the bike-mounted battery connector port and got a massive spark (I had no idea there would still be charge in my bike when the battery was taken out).

I could just spring for a new battery (or re-pack) which is NZ$1,200 without freight (Bike cost NZ$3,000 and is now probably worth about $700) and I'm assuming that the guy re-packing my battery pack would replace the connector but that wouldn't help with the connector on the bike.

Anyone know how difficult it is to replace the connectors? I thought I'd try that first rather than spend the money on the new battery pack when the battery itself still pumps out the power well.

Any advice would be great. Thanks,

Dom

 

[scrambler]

If the connector is melting something is definitely wrong, and at the very least you will need to replace that whole connector.
If you cant do that yourself, you need someone who can take it apart and check if there are more bad connections that may be causing your problem.

No point changing the battery if its connector is damaged and screwing things up.

 

[Dominator]

If the connector is melting something is definitely wrong, and at the very least you will need to replace that whole connector.
If you cant do that yourself, you need someone who can take it apart and check if there are more bad connections that may be causing your problem.

No point changing the battery if its connector is damaged and screwing things up.

Thanks mate! I think I will seek out someone that can look at the whole thing.

 

[hewstigator]

it's not for the faint of heart but here is a little walkthrough that will help you see what the process is:

Repairing a bad connector on the Reention Dorado downtube battery.

The Reention Dorado removeable downtube battery system is used on many brands of e-bikes including Hilleater, Juiced, surface 604, Volt bike, Smartmotion and Bitrix to name a few. With the Hilleater bikes we have seen no issues with this connection, but as the battery cases have grown bigger and...

hilleater.ca

it is important not only to replace the connectors, but also make sure that the receiving piece on the bike frame is not cracked or loose (if it is, it will just cause the new battery connector to go bad).

 

[Dominator]

it's not for the faint of heart but here is a little walkthrough that will help you see what the process is:

Repairing a bad connector on the Reention Dorado downtube battery.

The Reention Dorado removeable downtube battery system is used on many brands of e-bikes including Hilleater, Juiced, surface 604, Volt bike, Smartmotion and Bitrix to name a few. With the Hilleater bikes we have seen no issues with this connection, but as the battery cases have grown bigger and...

hilleater.ca

it is important not only to replace the connectors, but also make sure that the receiving piece on the bike frame is not cracked or loose (if it is, it will just cause the new battery connector to go bad).

Thank you! That's really helpful.

 

[Slaphappygamer]

That spark you got from your bike when the battery was not inserted. That is because the controller is holding voltage in its capacitors. To avoid this, press the power button a couple of times after removing the battery. This will discharge the capacitors.

 

[Gionnirocket]

Something to consider... and not for a novice, but..
IMO... the small rigid connections on this and similar batteries are inadequate in high vibration situations like an ebike, especially if riden spiritedly. On my first bike, a BBS02B build with a Hailong battery I had a similar failure within 3000mi. I can't see your photos or how everything goes together on your bike but if there's a way to slide the battery in place and then make a flexible connection or room to tuck some wiring away and then slide the battery in place it will be much more reliable. What I was able to do in my case was remove the connector on each end and crimp on a flexible lead with XT60 connectors. Install the battery and then connect it. Since the connection is now on the ends of two flexible wires the potential vibration damage is greatly minimized. Now an additional +8000 mi and no sign of wear/damage.
Again... You do need to have a full understanding and the proper skill_set to accomplish this. But I saw no reason to repair it with the same flawed design.

 

[harryS]

Happened to see these on a search for battery parts the other day,

 

[hewstigator]

Something to consider... and not for a novice, but..
IMO... the small rigid connections on this and similar batteries are inadequate in high vibration situations like an ebike, especially if riden spiritedly. On my first bike, a BBS02B build with a Hailong battery I had a similar failure within 3000mi. I can't see your photos or how everything goes together on your bike but if there's a way to slide the battery in place and then make a flexible connection or room to tuck some wiring away and then slide the battery in place it will be much more reliable. What I was able to do in my case was remove the connector on each end and crimp on a flexible lead with XT60 connectors. Install the battery and then connect it. Since the connection is now on the ends of two flexible wires the potential vibration damage is greatly minimized. Now an additional +8000 mi and no sign of wear/damage.
Again... You do need to have a full understanding and the proper skill_set to accomplish this. But I saw no reason to repair it with the same flawed design.

i agree there's a design issue with these connectors for the larger (heavier) packs. I got tired of cracking the top battery mounting plate on my bike frame (luckily much easier to replace than the battery-side connector) on like a yearly basis (my commute involves terrible roads) and just ended up adding zip-ties to help hold the battery to the bike so that those two end plates aren't the only thing holding the battery in and that has worked great but a little annoying to have to snip the ties whenever you need to remove the battery...

On the other hand I have a different kind of equally heavy battery with hailong style blade connections (on a different bike) with roughly an equal amount of miles and that has worked just fine stock without issue - never had to replace connectors or mounts or anything

 

[hewstigator]

PS if you are going to have to replace the battery-side connector, hilleater.ca sells a 'heavy duty' version of the male and female versions of the connector (larger lugs i believe):

Parts - Connectors - Page 1 - Hilleater.ca

hilleater.ca

I was toying with the idea of installing these but I have multiple batteries and i wouldn't be able to use those without replacing the connectors on all of them so laziness prevailed...