Battery melt

wvabeer wrote:
The guy told me to make sure the terminals were tight or this would happen. .... I guess I hate stripping threads...

X2

Can always get a torque wrench.

chuckftboy wrote:
Matt, has it right, the split lock washer made a bad connection. I've seen terminals melt on electric lift equipment from loose or bad connections a few times. Your cable end needs to be down on the terminal then a flat washer between the cable and the nut. No need to use a lock washer. Just check the tightness of your connections every now and then as part of your maintenance routine.
If you can get a good flat on the terminal for the cable to lay on, the battery will still work fine.

I'll change that, there is a shoulder at the bottom of the terminal after the melt so I found two washers to take up the space. There were no washer on there when it melted.

I'll change that

Ive welded batteries on forklifts its very safe to do so only if the caps are off! Do not mess with a freshly charged battery with the caps on ever they will explode. Other then that they make steel molds that u may be able to reweld a threaded terminal on the good side the issue tho is number 1 did that melt actually make a hole? Battery junk. Next is finding the mold and parts and a solder stick by far and away ur cheaper replacing it. If it was a 1000$ cell with multiple interconnectors weld er up!

The procedure is literally using an oxyacetleyne torch and running it over all the open caps to insure no built up gas is present then set the mold warm up the lead then add filler

Matt, has it right, the split lock washer made a bad connection. I've seen terminals melt on electric lift equipment from loose or bad connections a few times. Your cable end needs to be down on the terminal then a flat washer between the cable and the nut. No need to use a lock washer. Just check the tightness of your connections every now and then as part of your maintenance routine.
If you can get a good flat on the terminal for the cable to lay on, the battery will still work fine.

And didn’t melt the plastic? Wow

Matt_Colie wrote:

Wvabeer,

It looks like you put a split washer between the copper terminal and the battery lug.

If this is the case, that is exactly what you should not have done. The split lock washer was steel (a poor conductor) and caused the contact to be limited in area. Between those two, it didn't have a chance.

It is possible that you can run the lead back or clean it up to make an effective contact terminal again. But that may take so doing.

If you manage, go to a fastener shop and get brass or bronze washers and do not put any between the terminal (the copper part) and the battery lug. Then, go to all the other battery lugs that you did the same way and fix them too.

Matt

Just to add to this good advice: a split washer is not entirely a terrible idea for keeping the connection tight, but it should go between the nut and the terminal, rather than the terminal and the battery lug. The current carrying part of the connection is intended to be between the bottom of the ring terminal and the flat surface of the battery lug connection; while some current can (and generally does) flow through the threads and the nut to the terminal, it's not engineered to be the main path for it to flow through.

The springiness of the split ring washer is intended to keep things from vibrating loose. A toothed washer would also work to the same effect (and likewise should go between the nut and the ring terminal).

wvabeer wrote:
The guy told me to make sure the terminals were tight or this would happen. These are new so I added some washers and its tight. I guess I hate stripping threads, thats why it got hot. I think the next set I get will have regular top posts with heavy terminals. Sucks to have this happen to a new battery. Lessons learned.

Wvabeer,

It looks like you put a split washer between the copper terminal and the battery lug.

If this is the case, that is exactly what you should not have done. The split lock washer was steel (a poor conductor) and caused the contact to be limited in area. Between those two, it didn't have a chance.

It is possible that you can run the lead back or clean it up to make an effective contact terminal again. But that may take so doing.

If you manage, go to a fastener shop and get brass or bronze washers and do not put any between the terminal (the copper part) and the battery lug. Then, go to all the other battery lugs that you did the same way and fix them too.

Matt

one Can assume that the heat that occurred hot enough to melt that top lead may well have melted and damaged unseen portions INSIDE the battery. It seems foolish to me to not just replace the battery.

I can't figure out what happened. Do you have a picture of the negative cable connection? How did something melt down like that but still leave you a good tight connection? Shouldn't there be a gap somewhere?