[Tom Seeley]

Not a computer question at all, but I'd like an answer, and I bet someone here can help me.

I have a pair of wireless headphones that run on 3 nicad rechargeable batteries, so long as I keep the phones plugged into the charger when I'm not wearing them.

Is it possible or even likely that nicad batteries eventually get to a point where they can no longer hold a full charge? I.e., if I'm having trouble getting good signals, where I used to NOT have trouble, should I buy new nicads? Or do I need a completely new set of phones, etc?

[Elvandil]

NiCAD's, unlike most other types of battery, exhibit a "memory" phenomenon. When they are incompletely discharged, say to the half-way point, and then charged again, they "remember" the halfway point as their bottom and will only hold a half charge after that.

So, they need to be completely discharged, preferably every time they are used, but at least from time to time, so that they "remember" a lower minimum amount of charge. Otherwise, they eventually begin to hold less and less and need to be replaced.

NiMH batteries do not show this memory effect. Due to their power characteristics, they are not appropriate for devices that need a large initial power surge, such as electric motors on toys, but they are ideal for electronic devices. They also typically hold at least twice the charge of NiCAD's.

So, you need new batteries, and if you have the option, get NiMH.