Wow, that peak charger seems pretty cool, but an awful lot of work. Do you really want to charge your batteries to their absolute capacity, or get close with a lot less work? check this out:
Stand-alone charger tutorial
The thing to remember about dual-cells is to charge them at 4.5v or so, and that you will need to charge them for double the amount of time (because there's 2 cells being charged) to get the same run time as a single cell.
The charger in the above tutorial is based on a Motorworks charging base with a button to start new charges. With a multi-voltage adapter, you can charge cars with any number of cells on the same charger. 3 to 4 charges for single cells are perfectly safe, and 6 should be fine for dual cells. Once the cells start generating heat, they are full. I'm sure someone will disagree with me, but these little batteries are easy to come by and are cheap. If I ruin one, I've got a sack full of extras. I've been using the charger above for over a year, routinely get better than 25 minutes of run time and have yet to toast a battery.