# Melted Terminal!!!



## Coley (Jul 26, 2007)

I see that you were using regular battery clamps on the 3 other posts.

Were you just using the stud on the one that melted?

It looks like it may have loosened.


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## m38mike (Dec 27, 2008)

That's what I'm thinking has happened. The nut got loose, and the resistance went up, heating the connection and melting the lead. I didn't see it because it happened inside the battery box. 

The battery is otherwise still good. I'm thinking I may try to rebuild that terminal. I am thinking about cleaning up the post, putting a clamp connector around that post, put the bolt back into place, and pour some melted lead into the gap between the connector and the post. Or instead of using a clamp connector around the post, I may use a short piece of copper pipe and fill inside it with the bolt and some melted lead.

I had also thought about drilling into the post and running a tap into the lead so I could turn a bolt into the hole. The problem I see with this idea is that the lead is probably too soft to hold a bolt very tightly.


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## MN Driver (Sep 29, 2009)

That isn't what Coley seems to be saying. You've got 3 SAE post terminals and the one that is melted is a stud/nut terminal. The post terminals have a whole bunch of surface area and are usually less prone to backing off of the lead posts. The other one is a nut on a tiny terminal with very little surface area as it doesn't wrap around. Those connectors look completely different. I think you lost the post because of too much current through the stud connection you have, less so about it being loose which could definitely also be the case but usually ring terminals like you have there usually aren't very good for hundreds of amps unless they are larger rings. One looks to be not like the other.


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## poprock (Apr 29, 2010)

MN Driver said:


> That isn't what Coley seems to be saying. You've got 3 SAE post terminals and the one that is melted is a stud/nut terminal. The post terminals have a whole bunch of surface area and are usually less prone to backing off of the lead posts. The other one is a nut on a tiny terminal with very little surface area as it doesn't wrap around. Those connectors look completely different. I think you lost the post because of too much current through the stud connection you have, less so about it being loose which could definitely also be the case but usually ring terminals like you have there usually aren't very good for hundreds of amps unless they are larger rings. One looks to be not like the other.


 Agreed. As one who has melted many of my second hand T105 bolt posts I can say with some authority that they are unsuitable for EV's. The odd clamp in the pic is an auto lead type and will keep stretching until it breaks. The other two look like brass . I use a similar type now but with a smaller bolt; a stainless 6mm; and these have held well. In Aus they are sold by Auto One.


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## m38mike (Dec 27, 2008)

It's true, I haven't had any problems with the clamp style connections. But this is the first problem I've had with the flat end and post connection. I agree, I don't think that I had enough contact surface with the flat end against the top of the lead post. I really need to replace the end of this cable. 

My solution to this situation was to drill into the lead post and tap it for a bolt. But I did it in the center of the lead column that comes up through the top of the battery. The lead has a large flat area there. That gives me lots of contact surface against the flat end of the cable. So we'll see how well that solves my problem. There simply isn't any terminal lead left to try to rebuild the original style of terminal. So changing the end of the cable to a clamp connector wouldn't help me with this battery.


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## mizlplix (May 1, 2011)

Just pour another post. Easy to do and quick. There is a pictorial on how to do it. someone just recently posted one. How to Repair a battery terminal- in this section.

Miz


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## gsmith191145 (May 1, 2011)

I posted how to repair a battery terminal. It is located below. 

http://www.diyelectriccar.com/forums/showthread.php?t=61014


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## m38mike (Dec 27, 2008)

That's COOL!! Thanks! I've got a bunch of wheel weights, so the material is on hand. Did the new lead melt into the old lead enough to give you a solid connection? I'd hate to rely on the new led, only to have it break off on the seam between new and old.


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## gsmith191145 (May 1, 2011)

m38mike said:


> That's COOL!! Thanks! I've got a bunch of wheel weights, so the material is on hand. Did the new lead melt into the old lead enough to give you a solid connection? I'd hate to rely on the new led, only to have it break off on the seam between new and old.


To answer your question, yes it did work out great. Just in case I did not mention it. Spread soldering flux on the terminal before you pour your new terminal. 


Just to let you know, I melted down some lead bullets for my terminal that I had cast from used wheel weights. Enjoy.


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## dtbaker (Jan 5, 2008)

gsmith191145 said:


> T... I melted down some lead bullets for my terminal that I had cast from used wheel weights. Enjoy.


even better than swords to plowshares....


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