Ni-Mh VS. Ni-Cd Rechargable batteries?

Question

When using rechargable batteries which ones are better Ni-Mh or Ni-Cd. I recall that one suffers from 'memeory effect', reducing their effective life span but I can't recall which is which.

Answer 1

I guess Ni-Mh do have greater capacities and so on but Nikel Cadmium batteries are cheaper and can be charged quicker and abused more without deteriorating too much (i.e Ni-Cds don't mind being overcharged every now and then). I used to use Ni-Cd batteries long before Ni-Mh became cheap enough and the memory effect is definitely overrated.

I never noticed any lack of capacity over their life and I never discharged them fully, which is something you shouldn't do to a rechargeable battery too often (It's can cause cells to reverse their polarity and ruin their ability to hold charge and so on...) I have noticed though that some of my old Ni-Cd's are beginning to leak (Though they are ten years old or more). One big point though, Ni-Mh are safer for the environment and let's face it, overall they are better!

Answer 2

Ni-Cd batteries develop the memory effect. Ni-MH batteries need charging at a precise charging current, so use a smart charger for them. The self discharge time of a Ni-MH is slower than a Ni-Cd. Li-ion is the latest technology, with self-discharge rates comparable to ordinary Alkaline batteries.

Answer 3

My Ni-Mh always last much longer.