> Certainly =A0I've seen Gel cells go very high impedance and yet still
> charge very slowly and still supply volts at very low current only.

I had a standard auto battery go high impedance once.
I know exactly when it happened.
I don't think a pulse rejuvenator would have fixed it :-).
My wife Val will still, I'm sure, remember.

Few people think that I drive "well".
Val is not the least of my critics, but I try to not do things that I
think will get me killed or hurt anyone else.
Has worked so far :-). (One each of side on and head on car-mo'cycle
encounters in my past (me on bike) but they were the other guys fault
in each case)(the courts agreed).

Come home from town, Val as passenger.
Val had mentioned going to supermarket some while back. Forgot, I guess.
Just before supermarket across road on right (we drive on
left)(mostly) Val  reminds me.
Quick glance, road seems clear, swing across road.
Oops. Not so clear. Brain eye system was not quite up with reality.
No problem. Continuing the turn at this speed will easily take me into
supermarket driveway with no upsetting of other driver.
Upsetting of Val is less uncertain :-).
This is a VERY deep dip, normal speed of approach would be maybe 5mph.
10 mph would be pushing it.
Judgement says that this is the best approach. It's going to be a
little rougher [tm] than usual.
Ah well.
Into road edge dip, onto driveway, suspension bottoms, wham, nose
grounds, kerunch, kerboing, ...
Car LEAPS into supermarket driveway.
Other driver may not even have noticed.
Val did :-).
Putter around carpark to parking space, meekly taking the well
deserved verbal inundation.
Make mental note to not do that again.
Park car.
Shop.
.....
Leave shop.
Try to start car. Dead as a dodo.

Checking showed the previous good condition battery to still make full
voltage at currents less than 10 mA or so.
Above that ... .

There seems to be an upper limit of impact that such batteries can withstan=
d.
That's not new knowledge of course. Severe off road use is said to
reduce life time to months. Tubular would cells apparently handle this
far better.



         Russell

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