Hello everyone,

I am in the process of resurrecting a lot of lead acid Cells that I washed out, dried and sealed in the 1980's I shipped about 100 back to UK from the Oil Company in the United Arab Emirates. Some time ago I heard about using Alum, - Aluminium Sulfate as the electrolyte and I got about 30 - 40 cells working, OK.

As I do not need them at the moment I emptied them again and cleaned them out with rain water and some I actually removed from the plastic containers to clean out the sediment that I thought must have stopped a few of them from working. When I got them apart I discovered that some of the positive plates had broken off where they were all connected together and where the fat lead terminal went up to the top of the case. They had all fractured at the same place, although the rest of the plates including the negative ones seemed in very good condition. Only about 6 or 7 have fractured like this and I do not know why. The other question is how do I repair them. I can easily get at the fracture and I have filed the faces back to solid lead but I wonder what is the best way to repair them, providing a low resistance joint again.

Is it possible that solder, being a tin / lead mix will have a lower melting point than pure lead? If so, it will be fairly straight forward. the other way might be to drill small holes and clamp the pieces together with stainless nuts and bolts. The electrolyte is probably not going to effect the materials. Has anyone any thoughts about this before I start to experiment. I am going to make up a bank of cells to feed an inverter to provide a no break supply for a house. or to charge up during the day from my solar array, (4Kw)

Any comments will be welcome. Thanks George.

On 13/09/16 11:14, George wrote:
Is it possible that solder, being a tin / lead mix will have a lower melting point than pure lead?


Oh yes. You can solder lead easily.

--
"Anyone who believes that the laws of physics are mere social
conventions is invited to try transgressing those conventions from the
windows of my apartment. (I live on the twenty-first floor.) "

Alan Sokal

On Tuesday, 13 September 2016 12:10:21 UTC+1, The Natural Philosopher wrote:
On 13/09/16 11:14, George wrote:

Is it possible that solder, being a tin / lead mix will have a lower melting point than pure lead?


Oh yes. You can solder lead easily.

IIRC batteries are 'burned' rather than soldered, using lead not solder.

Wiki fwiw:
'All intra-cell and inter-cell connections are of the same lead alloy as that used in the grids. This is necessary to prevent galvanic corrosion.'

https://en.wikipedia.org/wiki/Lead_burning


NT

On Tuesday, 13 September 2016 11:14:42 UTC+1, George wrote:
Hello everyone,

I am in the process of resurrecting a lot of lead acid Cells that I washed out, dried and sealed in the 1980's I shipped about 100 back to UK from the Oil Company in the United Arab Emirates. Some time ago I heard about using Alum, - Aluminium Sulfate as the electrolyte and I got about 30 - 40 cells working, OK.

As I do not need them at the moment I emptied them again and cleaned them out with rain water and some I actually removed from the plastic containers to clean out the sediment that I thought must have stopped a few of them from working. When I got them apart I discovered that some of the positive plates had broken off where they were all connected together and where the fat lead terminal went up to the top of the case. They had all fractured at the same place, although the rest of the plates including the negative ones seemed in very good condition. Only about 6 or 7 have fractured like this and I do not know why. The other question is how do I repair them. I can easily get at the fracture and I have filed the faces back to solid lead but I wonder what is the best way to repair them, providing a low resistance joint again.

Is it possible that solder, being a tin / lead mix will have a lower melting point than pure lead? If so, it will be fairly straight forward. the other way might be to drill small holes and clamp the pieces together with stainless nuts and bolts. The electrolyte is probably not going to effect the materials. Has anyone any thoughts about this before I start to experiment. I am going to make up a bank of cells to feed an inverter to provide a no break supply for a house. or to charge up during the day from my solar array, (4Kw)

Any comments will be welcome. Thanks George.

You need a high tin solder.
This reduces the melting point to below lead.
And a large soldering iron.

I assume there is no actual sign of the joints corroding or having melted
due to current drain or anything like that. It is indeed odd they have
broken if neither is the case.
Brian

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This newsgroup posting comes to you directly from...
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"George" wrote in message
...
Hello everyone,

I am in the process of resurrecting a lot of lead acid Cells that I washed
out, dried and sealed in the 1980's I shipped about 100 back to UK from the
Oil Company in the United Arab Emirates. Some time ago I heard about using
Alum, - Aluminium Sulfate as the electrolyte and I got about 30 - 40 cells
working, OK.

As I do not need them at the moment I emptied them again and cleaned them
out with rain water and some I actually removed from the plastic containers
to clean out the sediment that I thought must have stopped a few of them
from working. When I got them apart I discovered that some of the positive
plates had broken off where they were all connected together and where the
fat lead terminal went up to the top of the case. They had all fractured at
the same place, although the rest of the plates including the negative ones
seemed in very good condition. Only about 6 or 7 have fractured like this
and I do not know why. The other question is how do I repair them. I can
easily get at the fracture and I have filed the faces back to solid lead but
I wonder what is the best way to repair them, providing a low resistance
joint again.

Is it possible that solder, being a tin / lead mix will have a lower melting
point than pure lead? If so, it will be fairly straight forward. the other
way might be to drill small holes and clamp the pieces together with
stainless nuts and bolts. The electrolyte is probably not going to effect
the materials. Has anyone any thoughts about this before I start to
experiment. I am going to make up a bank of cells to feed an inverter to
provide a no break supply for a house. or to charge up during the day from
my solar array, (4Kw)

Any comments will be welcome. Thanks George.

On Tue, 13 Sep 2016 03:14:39 -0700 (PDT), George
wrote:

Is it possible that solder, being a tin / lead mix will have a lower melting point than pure lead? If so, it will be fairly straight forward. the other way might be to drill small holes and clamp the pieces together with stainless nuts and bolts. The electrolyte is probably not going to effect the materials. Has anyone any thoughts about this before I start to experiment. I am going to make up a bank of cells to feed an inverter to provide a no break supply for a house. or to charge up during the day from my solar array, (4Kw)

Yes as to lower melting point, depending on the solder. (Though the electrodes
may be a lead alloy). Solder comes in many different formulations, so check.

It sounds as if the plates are accessible -- so look at "welding lead". From a
glance at some youtube videos, it looks as if it needs a small and hot torch, to
heat quickly while limiting the melted pool, and a filler rod. A spare plate
would provide filler of exactly the right composition, and avoid any problems of
introducing new materials into the plate and the chemistry.

Welding would be easier if some kind of form-fitting dam or backing is possible
-- silicone moulding, possibly?

Or is recasting the plates out of the question? (I ask because I've read of some
of your rebuilds, and the seemed comprehensive...)


Thomas Prufer

On 9/13/2016 1:07 PM, wrote:
On Tuesday, 13 September 2016 12:10:21 UTC+1, The Natural Philosopher wrote:
On 13/09/16 11:14, George wrote:

Is it possible that solder, being a tin / lead mix will have a lower melting point than pure lead?


Oh yes. You can solder lead easily.

IIRC batteries are 'burned' rather than soldered, using lead not solder.

Wiki fwiw:
'All intra-cell and inter-cell connections are of the same lead alloy as that used in the grids. This is necessary to prevent galvanic corrosion.'

https://en.wikipedia.org/wiki/Lead_burning


NT


+1