On Wed, 22 Mar 2017 07:21:53 -0700 (PDT), George
wrote:

I have read quite a bit about lead burning, but it does not seem appropriate for my requirement.

From a previous life in the Middle East I inherited about 100 lead acid cells. I emptied the acid out, washed them thoroughly with distilled water, then dried them in the sun, - there was lots of it! I sealed the tops and shipped them all back to UK. From time to time I have resurrected a few to make up 12 volt batteries and full of sulphuric acid they performed OK and lasted a reasonable time.

A few years ago I was looking at connecting a lot together to run a more powerful inverter. but it has become more and more difficult to get sulphuric acid, health and safety don't you know.

I discovered that the electrolyte could be change to a saturated solution of Alum (aluminium Sulphate) which is pretty docile compared to the acid and works as well. I got a bank working OK but soon noticed a few cells were getting a very high internal resistance and finally found that the positive cells were kind of corroded so as to break off and the junction of the pos. post and the bar holding the plates.

This was nothing to do with the electrolyte as even the ones full of acid were the same and fresh ones from my old stock showed a very weak join on the same place. I can only assume that the age of these cells has caused the internal corrosion in this area and it is only the Pos. plates which are affected, the negative ones are like new and very strongly connected.

I tried my hand at soldering then together, but failed miserably and tried to clamp the fracture together in one cell but the resistance of the clamped break, which I filed to give a clean metal to metal joint is very high and so the discharge current is tiny compared with a good cell.

So how do you weld lead stopping it all from falling into a molten mess?

The lead sections to be re-joined are quite thick at about a quarter of an inch, but it may need to be set up in a kind of jig, or mould, to allow the lead to flow without it all melting at once.

Has anyone any ideas of how I might recover so many cells without giving up the rest of my life to the task?

Years ago I went to a welding class and the instructor was an older
chap that had been welding since the days of gas welding only. He
recounted his experiences lead burning the walls of an x-ray room.
From his description he used a gas torch.

It was a long time ago but my recollection was that it must have been
much like gas welding aluminum.

Or you could watch https://www.youtube.com/watch?v=nm0o1g4ejys
or
https://www.youtube.com/watch?v=PzBK7S8cCGU
--
Cheers,

John B.