Mobile power in the charging of cell phones must be their own 3.7V voltage boost to 5V, this process will consume part of the power, coupled with the wire resistance consumption, the motherboard resistance consumption, and the mobile power in the case of non-use of their own power will be slowly lost, and finally be able to charge the cell phone inside the power is probably about 60% of the total capacity, for example, a 10,000 mAh Mobile power can actually charge to the phone, the power inside is about 6000 mA, you can give 3000 mA cell phone battery full 2 times, if a standard 10000 mA mobile power can not be full of actual charging 2 times, the mobile power is a false labeling capacity.