Its all about charger output power and what alipo requires for a given charge. A 4S charging at 1C will need 16.8v x 5a = 84watts. The currently sold 0606i is a 50watt output charger (AC) and will reduce the charge current to stay under its power limit, so with it you would get 50watts/16.8v = ~3amps. Thats all this charger can do because of its output power.

The new 0720 on the other hand would be able to charge this at 1C since its output power is 90watts. WIth only 90watts though, it won't do more like the 5C charge they mention - at least for your 5000mah 4S - a 5C charge rate for that is 25amps and would require 420watts, way beyond what charger is rated. There are smaller lipos though where you could take advantage of higher C charge rates if the lipo permits.

Lipo charging is a 2 step process - CC/CV - constant current followed by constant voltage periods. The CC is the charge rate and it charges the cells to the max cell voltage of 4.2v/cell. When the cells reach max voltage, the charger switches to the CV stage where it holds the cells at constant voltage and allows the cells to top off. You will see charge current decreasing during the stage, thats normal. It will go down toward zero current, how close it gets depends on the charge rate that was used. The charger terminates when it reaches this lowest current in the CV stage.

There is no set charge time, it depends on how deeply the lipo's been discharged, but folks have noticed, that at 1C for an 80% capacity discharge, it takes about an hr for both steps to complete. Charging at higher C rates reduces this time. Using the FAST lipo mode some chargers offer also reduces charge time since the charger in FAST lipo charge mode eliminates the CV step which is typically the longer time wise of the two steps.


Of these 2, the 0720 would be the better since it will allow you to do a full 1C charge on your 5000mag 4S lipos.