Originally Posted by
Davey
Some fast chargers for NiMH are not bad I hear, mainly the expensive ones, although in theory the faster chargers do shorten the shelflife quicker than slow charger. I suppose if you really need the fast charge it can come in handy but for most preplanning or multiple sets of batteries mean a standard slow charger is fine.
I personally side with colin and find a trickle charge more reliable, mine takes 26hours to charge a set. NiMH does have a limited life though which isn't quite as long as some lithium ion as far as cycles goes. They do last longer full to discharged wise than alkalines or some lithium (but not single use lithium like cr123 type, I can't remeber what they are but there are 3 types of lithium cells if i remember correctly). Also they work at low temperature which is ideal and most of all they are cheap. Don't pay over the odds for the very high mAh because it's a bit of a marketing thing and not exactly what you'd think. I use 2200 aa in my flashes that only cost about £3 per 4 and the same in my camera.
Oh NiMH don't have memory like NiCd do which can also be a bonus all though I always run them down before charge it can be handy if you just want to top up half depleted ones. There is one prob with NiMH I have found though and that is they run slightly over 1.5v when new which can be a problem driving some devices with regulators, some torches etc but they generally have specialist size Li ion batteries and manual and packaging often informs it's not NiMH compatible on such things.