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Battery terminal has crack on it

Does anyone know what type of metal this is and if I can weld some onto it? Car barely has a crank if I don’t drive it for 24 hours straight

Kia amanti 2004

Battery is tested and it’s decent. Id rather not have to pull this plug. Would quick steel work?

Looks like it is a structural as well as electrical part - those relays are held by it? Looks like aluminum but may be steel - try a magnet. To repair it, I would think about bridging the gap with a strip of the same metal, held against the part with a few small self-tapping screws or small nuts and machine screws.

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Yes the relays are connected which then has a cord attached. I’m really confused on what metal to use. I’m afraid a magnet will cause internal damage.

Would a lead terminal shim work? If so can I just electrical tape it

I have some welding type rods that need only heat from a propane torch. Is getting a new piece of hardware an option?

@Barkydog I have a propane torch. What else do I need? Would lnt stuffing some aluminum foil in the gap work?

from corrosion mark next to battery post, it looks to be a ferrous metal, so soldering is the option to entertain

remove that piece from the car, get some soldering paste and solder from the hardware store, clean it up with a file, apply paste, heat it and apply solder, should do it

usually it helps to run it with soldering iron to get solder to “stick” to the site

I doubt stuffing foil would be my first choice., Google propane welding rod if you wish to try some, 5 bucks or so.

I think I see a cable also connected to that battery clamp - is that correct? And this is the negative post, right? I doubt that bracket is carrying the starting current. Have you removed and cleaned both battery clamps and posts?

Scratch it a bit with a knife edge or file if you want to know what kind of metal it is. I think below that silver coating, it’s probably copper or brass. Not sure brazing or soldering is going to hold… Going to be hard to solder or braze that crack back together stronger than it originally was when intact.

I may be crazy, but I think I’d drill a hole through the crack near the top. Push the pieces back together before drilling to make the crack as narrow as possible. Then put a short bolt in, a flat washer on each side, and a nut on the back and tighten it down as a clamp to hold the pieces together. Then you can do your soldering or brazing.

My first choice would be to find that part either new or at a salvage yard and just replace it, though.

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Actually, it may be the easiest to do and the longer lasting repair: just make a hole, get the bolt there and it will happily act like a bridge for electricity.
If it works, it would make sense to spray some paint atop to prevent corrosion.

I don’t think it’s cracked, looks like it should be that way.

Your battery/terminal connection doesn’t look very good though, needs a good cleaning, probably the other post also needs a good cleaning.

The edge is not square, looks like a cut from some grinder/cutter disk to me.

at 3+ years on that battery, I’d be looking real good at it if you are having starting issues. I agree with @texases that the broken (cut? designed that way?) metal piece is likely not carrying the starting current and shouldn’t have much of an effect on the starting of your vehicle.

No, it won’t.

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Yes, and all those other connections there held together with nuts and bolts - I’d take those apart, clean them of corrosion and reassemble.

I believe your problem is a parasitic current draw on the battery as the vehicle sits.

Tester

Yeah, I doubt fixing the crack (if it’s cracked) will solve the starting issue.

I kinda got fixated on repairing the crack to keep it from breaking off and overlooked the cranking issue.

To be honest, it looks like somebody went at the thing with a cutoff wheel. I don’t think that happened, though. Just looks like it.

If the crack is preventing robust cranking, your shop should be able to measure a significant voltage drop across the crack during cranking. 1/2 volt or more. That’s a very easy test. What do they measure?

Please let us know what you finally did to fix the problem.
Did you check out replacing the part? I would investigate that first before trying to ‘fix’ the existing part.
Did you check for parasitic drain?
Is your alternator charging the battery correctly?
Repeated discharging will shorten the battery life-most likely your battery should be replaced.

If one gets to that thing with a multimeter, the good idea would be to measure voltage drop during cranking not only across the gap, but between the battery post and the clamp… and simply between the battery terminals - that two tests should tell what part is at fault right on the spot.

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