Conversion rate of mobile power bank

First,we would like to briefly explain the charging principle of power bank,the battery of current power banks are 18650 and lithium polymer battery,the nominal voltage is 3.7V,but the standard input voltage of the digital products is 5V.Therefore,power bank need to boost to 5V to charge the mobile devices.
 
According to the principle of conversion of energy,power bank with 6000mah,the capacity energy is 6000mAh x 3.7V=22.2Wh(瓦时),after booster into 5V,the overall energy remains unchanged.But the capacity is 22Wh/5V=4400mah.Just like a glass of 3.7 liters water pour into a 5 liters cup.Through the first step conversation,the original 6000mAh capacity only 74%,the 4400mah capacity is actually can supply to digital devices.

Whether the 4400mah capacity canfull supply to the battery of the digital devices?The answer is no,while charging ,it will cause energy dissipation and loss.
1.Circuit switching loss.
2.The resistance loss.
3.Voltage loss.
4.Power supply loss.

Exmight power bank factory would be very happy to offer you the high efficiency,high quality and unique desigh power bank

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