I'm trying to source a replacement lithium ion battery for a laptop (an
Advent 6412 as it happens). The original is rated at 14.8V, 3600mAh.
Various vendors seem to have correctly-shaped batteries at this voltage but
at 3900mAh, 4000mAh or 4400mAh. I've read that Li-ion batteries are rather
fussy about their charging capability to prevent them exploding. I know
with NiCds you can replace batteries with higher capacity ones without
problems: it may be that the battery management circuit won't use the
extra capacity but that's not a big deal. Does this apply to Li-ion
batteries too, or must the capacity be an exact match? I can see potential
for the on-battery processor just telling the laptop it's a higher capacity
battery and amending the charge regime appropriately - is this what happens
to make use of the extra capacity?

Thanks
Theo