Please see this link:
http://en.wikipedia.org/wiki/Aircraft_battery
Some D batteries are made up of alkaline, zinc-carbon, lithium iron disulfide, nickel cadmium, and nickel-metal hydride.
A D battery is one of the most recognized batteries available. However, there are many types of D batteries. The most standard is the alkaline. It is not rechargeable. Those made of lithium, also non-rechargeable, offer a greater life than the alkaline. There are two types of rechargeable D batteries. They are nickel metal hydride and nickel cadmium. The nickel metal hydride are now preferred as nickel cadmium are said to have environmental effects.
NiCd Nickel & Cadmium
Yes. It's used in Nickel Cadmium and Nickel Metal Hydride batteries.
Nickel and Cadmium are two elements, both metals. They are used together as the principal componants in rechargable Nickel-Cadmium (or "NiCad") batteries.
Nickel hydrogen batteries have been introduced as an alternative to nicads. They possess a greater capacity and boast environmental benefits since they do not contain cadmium.
That is nicad, pertaining to batteries.
You can find nickel cadmium batteries in many stores. The place they will most likely be found at is a special manufacturer or by ordering them online but they can also be found in stores like The Home Depot.
Mostly because they don't contain nickel, and especially cadmium - both very unpleasant environmental pollutants.
Nicad is short for nickel-cadmium
Anything. They don't pack as much energy as NiMH or Li-Po batteries though.
Nickel Cadmium batteries can last through about 2000 recharge cycles.