Discharge Curreunts, NiMH > NiCd?

NiMH & NiCd Discharge Current

Ive been reading up more on batteries lately and what I first learned was that NiMH can discharge higher currents than NiCd and also have higher capacities than NiCd. No one seems to deny the higher capacities of NiMH over NiCd, but some places seem to say that although NiMH has higher capacities, NiCd can supply higher discharge currents, contrary to what I have learned.

Anybody know which is which? Batteries being the way they are...lots of misinformation floating around.

I don't know, but portable tools are still using nicad.

I remember that NiCD are more robust than NiMH batteries. In the RC communities where they discharge 2AH batteries in 10 min flat, it took a while for NiMH batteries to gain a foothold. Continuously trickle charging NiCD batteries was reasonable, and I think they were capable of more charge/discharge cycles than the NiMH batteries before seeing similar amounts of degredation.

One trick might be that NiMH batteries have increased in capacity enough that the relative "C" current that they can output has increased enough to balance out the NiCD's inherently lower impedance.


[after google searching randomly...]
**broken link removed**
There's a neat little chart in the middle which seems to correspond to what I remember...

Energizer's 2500mA/hr Ni-MH AA cells have a lower internal resistance than their obsolete 1500mA/hr AA Ni-Cad cells, so they can supply higher current with the same temperature rise. With nearly double the capacity they can work nearly twice as long.