Also take a look at my suggestions here: http://www.8052.com/forum/read.phtml?id=73579

Follow the first link I give at the end of that post. You 'll find many interesting things about batteries.

It's not that difficult to calculate the time you need to fully charge your batteries. An example: If for a recharching chip the manufacturer says that the maximum current it can give is 5CA (Capacity Amperes), this means that the chip can provide current equal to 5 times the capacity of the battery that is going to be charged. So after that you can do your calculations. Usually it is you that can adjust the charge current. Of course you have to read the datasheet of the chip you 'll select to see if that's possible and if yes then how you can do it. Battery manufacturers for fast-charging suggest to use charge rates of no more that 1CA (at least for NiMH batteries), but for more details click on the above link and the link provided by Raghu...

Only one question: Why do you use NiCad batteries? NiMH are a little bit more efficient (but not THAT much) and they have the big advantage of not having the "memory effect" (at least the new generation of NiMH).

George