This one is only good for nicads and nimhs. There are a lot of other ones out there but I am not going to spend too much time searching for you. This one has selectable charge rates from .1a-5a and works with ac/dc input and is only 41.99
For your 2000ma battery you would select .2a charge for overnight.

http://www3.towerhobbies.com/cgi-bin...LXTSA4&P=7

This one does not cycle batteries though. You will need to spend more money for that option. You don't seem to want to spend a lot right now so that is why I showed you this one.

As JB pointed out field charging nicads/nimhs is a bad idea so if you want to do that I would switch to lithiums.