In article ,
Peter Crosland wrote:
The battery pack says charge for 16-20 hours. Will I damage them if
they stay on charge for, say, 3 days or more ?

That depends entirely on the charger - not battery. So you'd need to
look at the instructions for that. If it obviously switches off after
charging it should be ok.

Wrong! It depends on both.

Wrong! It doesn't. ;-)

You need to use a charger designed for the
type of battery you wish to charge. For example Ni-Cad cells need a
quite differnt charging patter than say Li-Ion ones.

And how is this relevant? FWIW, there are battery chargers that cope
automatically with both types and varying number of cells too - and switch
off at the end of the charge cycle.

Is it advisable/necessary to use/discharge the batteries totally
before recharging, or can I recharge them when they are half used.
They used to say that rechargeables developed a "memory" - is that
still true?

It never was. It was a con to persuade you it was your fault batteries
didn't last.

Wrong! It was not a con at all, but has been repeatedly proven by
experiment. Ni-Cad cells are particularly prone to this.

Wrong! It has not been 'proved' at all under normal use.

I've seen advertised charges that will recharge ordinary
non-rechargeable batteries. Are these any good ?

Wrong again!

Have you missed something?

They do work but not very well. Not a good choice really unless you are
desparate.

No. And rechargeables cost so little more anyway.

Wrong! Unless of course you regard a price difference of at least 50% as
being insignificant.

FFS, it is insignificant over the life of the battery. 'Recharging'
alkaline batteries only partially works - and only even that for a few
times. As opposed to hundreds of times for a Ni-Cad or NiMH.

--
*Never kick a cow pat on a hot day *

Dave Plowman London SW
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