Batts.

[BrianG]

You are referring to a balancer. Basically, charging the batteries IS just like you describe: plug them in, set your charge current, number of cells, and go. The balancer just monitors each cell in your pack to make sure they are getting the same charge. Think of it as having insurance for having matched cells at all times.

Whatever charger you get, the Hyperion LBA10 is a nice balancer and will take care of you.