Corroded battery terminals

[profdc9]

I just fixed a shortwave radio tonight (Tecsun PL660) that I had left batteries in and became corroded.

One thing I did, which I am not sure is a good idea, is I used lead/tin solder to tin the spring contacts which touch the battery terminals.  I used paste flux to help clean the corrosion off and then applied some solder to try to form a new surface on the wire.  Then I cleaned off the flux with a cotton swab and alcohol.

Has anyone else tried this?  I am just curious. I am not sure if the contacts were tin plated in the first place, or plated with some other metal.

[abdulbadii]

depends on terminal plate damages, if bad then replace it with proper substitute with wire goes into it being lengthened and soldered its end to the plate with flux and/or (additional) mild/strong acid if too difficult doing it with only flux, then must quickly be cleaned up with IPA applied cloth, and get wiped, dried outright, and put and position it back exactly as it was

if not too bad just clean up by aid of cooking oil mixed with mild acid and a bit of water (should always readily have this chemical kit in small closed bottle) while rubbing it with fine sandpaper,  cleaning up with IPA applied cloth and drying it up fully

[paul_g_787]

I had this once on an Xbox 360 controller and I did exactly the same thing you did. it works fine to this day still.

Also the lamp holder in the headlamp of my father's 1970s Suzuki corroded. I basically did the same with this and tinned the whole thing with lead solder. Still works 6 years on.

I also had a PS3 Blu-ray remote where the batteries got left in and the terminal completely rusted to nothing and was not salvageable! Luckily it was the 'flat' one and not the 'spring' one, so I coiled a paper clip round and round to the same diameter as the original and hammered it flat on the anvil until it was thin enough to slide in to the slot in the remote. Then tinned it with solder and joined it to the other terminal.

[profdc9]

Well it's good to hear that the method worked for someone.  I am not sure what metal one could use (except for gold for example) that would be resistant to the potassium carbonate of a corroded alkaline cell.  Solder is the best answer I could come up with, even though lead and tin are amphoteric and probably can be corroded by another leaky battery.  I guess it holds up for awhile.

[cvanc]

Normal kitchen vinegar does an amazing job of cleaning off the 'crust' of a corroded battery terminal.

[abdulbadii]

...mild/strong acid if too difficult doing it with only flux

did read it, didn't.

"Only worked for someone", no, meant you haven't used adequate strength of acid which if it really is, it's absolute working

[madires]

White vinegar works great on crusty battery terminals. For mildly corroded terminals you can use a glass fiber brush. If the plating is worn I also simply tin the terminals. I fixed a ton of gadgets and power tools this way.

[David Hess]

The terminals were probably nickel plated.

I have used the same repair method to apply tin/lead solder to corroded battery terminals and never noticed any decrease in reliability.

[RoV]

Last time it happended to me, I wanted to do a perfect restoration.
It was a conical spring (for the battery "-") copper plated with nickel: Ni had gone away and copper was brown.
After some rubbing, I immersed the spring in diluted HCl to remove the copper oxide, then washed.
Then I used a galvanic bath with NiCl + a bit of HCl, a nickel electrode (of the kind used to connect lithium batteries) and ~3 V (negative on the spring).
Result was perfect! Just a bit time-consuming... But I wanted to use a bit of the NiCl bought some time before on eBay, although I was a bit scary, because it seems it is a particularly toxic salt.