Don, I would use at least a 1700 ma pack. When a pack lays around it will tend to "false peak" when you try to charge it. So you need to use something to charge them slow and make sure they are fully charged. I use to have a device that would cycle the packs which was good because it told me how long it took to discharge the pack. It was good for weeding out bad cells. The charger I use now has adjustable amps and also a trickle setting. You should observe the pack when it is charging to get a feel for what is right also. You may see it "false peak" after a few minutes and you'll know it is not fully charged. I usually charge my 1700 ma packs at 3amps. The battery manufacturer should be able to recommend how to charge the pack. Just my two cents worth.