by SeaMonkey » Mon Aug 03, 2009 6:49 pm
Mael,
The two patents listed below are very interesting in
their assessment of the lead acid battery and why it
tends to fail.
The first is quite comprehensive in its review of various
rejuvenation techniques and the internal chemistry of
the lead acid battery.
The second is a charging methodology that claims to
produce very good results and is easy to implement.
Both are .pdf documents and can readily be found
by means of a web search.
US20060051659
US6130522
Mr. Buchman at Battery University has an interesting
opinion as to why battery failure is such a common
problem in Japan. Have you seen it yet?
You'll find it
I'm beginning to think it is the sulfation which has crystallized
deep within the plate structures that is so difficult, and time
consuming, to revert back to active materials. Until that level
of sulfation is reversed, the plate structures will be impaired
in their ability to charge/discharge effectively and their
capacity will be greatly reduced.
But, what is a reliable indicator that this deep sulfation is
indeed the problem?
Long term desulfation, at a relatively slow pace, seems to
offer one possible means of getting to it. It has been
suggested by some that a periodic 'burp' (a high current
discharge pulse) is very beneficial in getting into those
deep pockets of sulfation which most resist rejuvenation.
As you've pointed out, physical plate deterioration is a
problem which must not be accelerated by rejuvenation.
I'm thinking that the slow, low power pulsing, is best able
to avoid putting additional stresses on the plate structures
so that the de-sulfation can take place without abrupt
physical displacements.
It would be so very illuminating to have a way to 'see'
what is happening at the microscopic level in the
process. I've dismantled an gell battery that was non
responsive and have very carefully removed the plates
and packed them in tissue for future examination.
Perhaps I'll take a pair of those plates and construct a
cell in a jar and pulse them for a long period. This will
allow close inspection of the plates before, during, and
after treatment and may provide some visible clues.
There it is; one more project on the growing list of
things to do! We definitely need some 36 hour days!
This is what I have learned so far; the spiral plate cells
which are cylindrical in shape, seem to be the best.