The 13000mAh is rated to charge Apple devices a specific amount of times. 4.5 X for an iPhone 6 (4.7 inch screen), 1.9x for an iPad mini and 2.5 times for an iPhone 6 (5.5 inch screen). To charge the power bank to initial full capacity, from the indicated 80-100% out of the box, took twenty-five minutes. (0:25). For this review I chose to charge an iPad mini two times, to verify the manufacturer’s stated capacity. The OLALA S100i easily charged my iPad mini 2.3 times, performing above my expectations. Once drained, I next charged the Power Bank to full capacity, which is estimated to take 9 hours. Using 5v 1.8A charging cable, the time required to full charge the OLALA S100i 13000mAh was 8.75hrs . Using a quicker charger would definitely shorten the time; however the increased heat may damage the power Bank.