Melted battery terminal

[beachguysc]

About a mile from my house yesterday, I noticed a burning smell so I immediately pulled over to find my main pack negative terminal melting into the battery. I was told this can be from loose connection, bad crimp, or corrosion. But none of those seem to be a factor in my case. Except possibly bad crimp, but the copper is still attached solid enough that I can’t pull the end off with pliers.
-My batteries and 2 gauge cables are just 6 weeks old and there is no corrosion. -All my other terminals are tight and this one had the same thread depth over the terminal nut as the others.
-And I had just checked the nuts and water level a few days before.
So what else could it be?
I also checked the connection on the other end of this short cable where it goes into my obc. There was no apparent heat damage on the onc end of the cable. I had done the homemade work around and that end was tight between two nuts. There is some minor play where the bolt goes through the obc, but that is because I didn’t want to tighten it so much that I crushed it.
At best I’m out $120 or so dollars to go buy a new battery.
Before I sjust slap a new battery in, I want to make sure this didn’t spread to, or get caused by Any other parts. Is there any way to check? My biggest fear is I go an buy a new battery and it happens all over again, or worse. Any guidance on on how to proceed would be appreciated.
Is there anyway to know if the battery caused this? I know that is a long shot and probably impossible to prove with the amount of damage already done to it.
- The only other symptom before the burning smell was erratic speed pulse, like an mcor pedal issue. But I also just replaced the mcor a few weeks ago, too.







photoupload

[NCPW]

If there's no other great damage to any part of that cable, possibly a loose connection internally in the battery.

Is it possible you might've over tightened that lug causing it to break loose from the lead inside the battery?

Check with vendor you bought the battery from. Maybe they'll warranty it since it's only been 6 weeks.

[LukeL]

My dealer covers everything on batteries under warranty except for melted terminals. I had to replace a brand new Powertron the other day because of this problem.


Club Car DS driver’s club #59

[Fairtax4me]

Loose terminal = melted terminal.

[Sergio]

It doesn't seem to have too many exposed threads in the picture with the melted terminal, was there anything between the cable lug and the battery lead surface?

What kind of crimper did you use? The cable lug under the green shrink wrap looks almost undisturbed and the flared end seems much larger diameter than the cable copper strands.

[Cynikal.Mindset]

were those soldered lugs? if not they don't appear to be crimped well enough at all...if they were soldered they probably weren't done well and were loose inside the sleeve causing you problems

[Dlab]

Originally Posted by Cynikal.Mindset

were those soldered lugs? if not they don't appear to be crimped well enough at all...if they were soldered they probably weren't done well and were loose inside the sleeve causing you problems

This^^^^^. There’s too much wire showing in the heat shrink also. Just doesn’t look like a well constructed cable. No offense to whoever made them.

[WalterM6]

Remove the shrink tubing from the cable and inspect the solder joint. It should be nice and shiny. If not you have a cold solder joint. If you used 60/40 solder it is likely you have a cold solder joint. They are caused by any movement during cool down. To avoid use eutectic solder 63/37 alloy.

[beachguysc]

Originally Posted by Sergio

It doesn't seem to have too many exposed threads in the picture with the melted terminal, was there anything between the cable lug and the battery lead surface?

What kind of crimper did you use? The cable lug under the green shrink wrap looks almost undisturbed and the flared end seems much larger diameter than the cable copper strands.

Originally Posted by WalterM6

Remove the shrink tubing from the cable and inspect the solder joint. It should be nice and shiny. If not you have a cold solder joint. If you used 60/40 solder it is likely you have a cold solder joint. They are caused by any movement during cool down. To avoid use eutectic solder 63/37 alloy.

Thanks to everyone for the input. I did remove the shrink wrap and there is some silver up under the lug where the cable goes in. The gap between cover and lug was not there Before the melt down. (See before/after pics below) Also, there was nothing between the lug and terminal and I confirmed through pics that thread count above the nut was the same as the other cables. These cables were made by a guy in GA and I posted a quote from his sales ad below. They do feel like well made cables, and the guy seemed like a knowledgeable straight shooter. But I know pretty much nothing about soldering/crimping 2 gauge cables. Thanks again for the input.

“One set of eight 2 gauge battery cables for Club Car Precedent 48 volt with four twelve (4x12) volt battery setup. These wires are made from premium 2 gauge welding wire. The connectors are 2 x 3/8 copper lugs with tin coating or solid copper lugs with no coating, your choice....copper lugs will be an additional $.50 cent each, with each cable requiring 2. (PICTURE SHOWS BARE COPPER, they will be tin unless ordered with bare copper!) I don't use cheap connectors on my big gauge wires! Make sure you don't get the big gauge wire with crappy little connectors like so many here on eBay do! Each wire is made custom in my golf cart shop by me. Each one is soldered using premium silver solder connections, and then sealed with high quality heat shrink to help prevent future corrosion issues.“

[joesam]

That looks like a lock washer on the obc stud. Is that a good idea? I would think a flat mating surface is better.