Basically when I talk about rechargeables, I talk about NiCads and NiMHs. Their behaviour is very similar regarding the charge and discharge process. In general one could say, a NiMH is just a better NiCad. One application is still a NiCad center of gravity: High current applications, like in car modellmaking. NiMHs have a better capacityweight ratio, so given a certain size, NiMHs just have a higher capacity. Another major advantage is their nearly lack of a memory effect and a lower self discharge rate. Of course there are significant differences in the chemical process inside a NiCad and a NiMH cell, but as long as you dont want to build your own battery, we dont have to worry about that. One word about renewals: They are no rechargeables from my point of view. They are merely modified Alkalines so called primary cells and bascially designed for one time use only. Its still unclear whether some normal Alkaline brands on the market are not also renewable. Anyway, the handling difficulties, the relativ expensive chargers, the short lifetime and last not least the price versus a true rechargeable makes them a bad choice. The only reason for renewables would be their higher cell voltage, but especially the Palm doesnt need that. Its working at a voltage range of 22.6V as well as at 3V. In fact, due to the low overall consumption, the Palm is predestined to work on rechargeables. And before you ask: Lithium rechargeables are also a total different story. They have an excellent capacity weight ratio and they are damn bitchy with their handling. Charging them without some sort of intelligence is not possible well, it is ... one time, theyre temperature sensitive and they are very expensive. Last not least, a single Lithium cell has a nominal voltage of 3V. So rechargeable AAAs will be very unlikely.

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