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how do i convert lead sulfate from a "dead" battery back into sulfuric acid and lead? Answered

hello, i just ripped apart a sealed lead acid battery,
and have salvaged the plates, but now i have a problem, two actually

i have two types of plates
one is red-brown, the other, light grey , which i suspect is just lead, which, through my powers of deduction leaves me to beleive the redish crystaline substance that makes up the positive plates must be lead sulfate.

what i want to know, is what this red substance is,
and if it is lead sulfate, how do i convert it into sulfuric acid?
ive tried electrolysis, but the ph doesnt seem to change beyond normal, for plian old hho electrolysis!

am i getting something wrong here?



7 years ago

A quick glance at Google images for led oxide
shoes that lead oxide is red


8 years ago

To convert lead sulphate (i.e. just SO42-) to sulphuric acid, you need to add an acid of similar strength (and sulphuric acid is pretty strong...)

What you do is boil the liquid that was in the battery until it's "fuming".



Answer 8 years ago


the water in the battery had a neutral ph, of 7.5, its a dead battery.

so your saying i require another acid to act like a sort of "catalyst"?

makes sense, i got two of the grey plates electrolyzing, and the ph became acidic, it also started electrolyzing better.
but then i accidentally spilt it, and i haven't been able to the same plates, nor two others, to electrolyze even within a millimeter of each other.

it seems ill have to add a bit of copper sulfate to the mix then

one last thing, as it appears to me that the grey lead-like plates are infact lead sulfate, what are the reddish-brown plates?
are they some kind of lead sulfate? or red lead tetra-oxide


Answer 8 years ago

It's acid-base equilibria:

SO42- + 2H+ = H2SO4  (you need a source of H+, i.e. another acid)

Electrolysis produces hydrogen gas

The red stuff would be oxide I guess, I've got a load of it myself...