[Unsullied_Spy]

I had a 5i for about 3 years and while it is a good charger, it takes a while to charge being a low wattage charger. It should be charging those 2s packs in about 90 minutes though, it still has enough wattage to maintain 5 amps all the way through the CC part of the charge. Are you saying it takes 3 hours to charge both of them or 3 hours each? 3 hours for both is typical for a 1C charge rate due to the CV phase of the charge, 3 hours for 1 battery means something is wrong. I replaced mine with a 1210I and have been charging "1C" charge rate lipos like my Rhino 2150 packs at 1.5 and 2 C without a problem and they get done in under an hour (and you can set it to only charge to 80%, which cuts a LOT of time off the charge if you're in a hurry).