How fast your battery charges depends on the amount of power supplied, the battery capacity and the size (mAh).
It all comes down to number of batteries charger and if you charge via a Micro USB outlet on the mod itself or a separate battery charger. But expect 4 hours roughly if you charge in a separate charger. When charging through the Micro USB port you can count on at least 3 hours per battery..
It is not possible to say exactly how long the battery takes to recharge, but you’ll find out after a few days use.