ORIGINAL: geezeraviation
Most batteries benefit from charging for a long period at the ''C'' rate or 10% capacity ie 1000ma pack charge at 100ma for 15 to 20 hours. I have been told you can plug in a ''C'' rate charger and leave it basically indefinitely. I still do ''C'' rate charging in the shop. I have several spare (un needed at this time) packs in 4.8 and 6v and about every six weeks or so I cycle them down and put em on ''C'' rate for a day.
I doubt if you hurt your batteries with the ''wall warts'' they're pretty safe as far as leaving them on for extended periods.
Doc
"C" rate is the battery capacity. That would be 2 amps on a 2000 mah pack. Too high for the initial charge. You want to "break-in" the pack on a 1/10 "C" charge for approximately 15 hours. as mentioned above. I quit using Nicd batteries in my Tx. NiMh work just as well without "memory" problems. Although Nicd's can take heat abuse, Nimh batteries need to be carefully charged so that they do not build up heat which can destroy them. Capacities on NiMh batteries above 1000 mah should not be charged over one "C" (1 amp on 1,000 mah capacity).
I have also used the eneloops with good results. We have a local battery store that makes up packs with your connector for about $18 on a 2500 mah capacity.
abufletcher,
You can try this place for reasonably priced batteries:
http://www.batteryspace.com/96vbatterypackseries.aspx
They also have a warehouse and production in China:
http://www.batteryspace.com/contactus.aspx
Their Japan office is here:
http://www.batteryspace.jp/
Bob