I am saying, for our trains don't sweat the composition of the battery, it will never matter. Just buy a quality battery and don't get distracted by the fluff. You can go on and on about NiCad and deep cycles, memory effect and what ever. BUT go look at your cordless phone if you have one. NiCad, constant trickle charge and NEVER deep drained. The last set of phones like that I replaced at 12 years old, when the batteries finally became useless. Cheaper to by new phone set than replace those batteries.
So again how the system operates matters. Much of what you stated while factual is not applicable for our trains and you would never know.
I see NiCad routinely still good over the 5 year period for 8.4. I do change them since folks sending engines to me do not want to open. I install MTH batteries when batteries called for and install Supercaps when folks want that option.
If you order batteries from MTH you will get NiMH for 8.4V and NiCad for 2.4V AA and NiMH for 2.4V AAA. That is what they supply. By the way the 2.4V AAA do not last nearly as long as the AA NiCad. The capacity of the AAA is a factor, but I imagine the composition factors in too.
I would use the oil analogy a little different, do you really sweat the oil type used if you routinely change it at 3000 miles. Walmart brand is just as good as a name brand if it meets the industry spec. You will never see or notice the difference in engine life. G
