In article ,
Jim Adney wrote:
If the battery is sulphated, most modern chargers won't deliver enough
volts to get anywhere near 5 amps due to the high cell resistance. Many
are voltage limited to perhaps 14 volts or so, and might need several
days to get any result - if ever.

That's probably for the best anyway. A sulfated battery should never
be charged at a high rate. That will just hydrolize water and can
damage the plates. IF recovery is possible, and it sometimes is, then
your best bet is with a very small charging current over a number of
days. I find that a week is typical for a car battery, but I had one
that took 2 weeks.

Yup. I was just worried someone might try using a variable bench supply to
push through the 'required' 5 amps if their charger didn't do this.

If you insist on instant gratification, you should just buy a new
battery.

Think you'll end up doing this anyway. ;-)

--
*Stable Relationships Are For Horses.

Dave Plowman London SW
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