NiCads develop a memory over time and can't be fully recharged unless
they are fully discharged occasionally. Lead acid batteries don't
develop a memory but do start to shed lead from the plates when they get
very low.

As a practical matter you really can't get more than about 35-40% of a
wet cell's capacity out of a normal cycle while cruising. They should
not be discharged more than 50 to 60% and when recharging that last
10-15% takes a long time. Up to about 80% you can safely push 25% of
the capacity per hour back in but above that the rate of charge drops
quickly.

Stefan wrote:
In article ,
says...

100AH is its total capacity. Normal rule of thumb is to only
discharge it down to 50%. So, you have 50AH of useful
capacity.


The advice for NiCad batteries for mobiles etc. is that it is good for
them to go through complete discharge-recharge cycles. Anyone able to
explain why lead/acid batteries are different - if indeed they are?

--
Glenn Ashmore

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