How Many Times Can a 20100mAh Power Bank Fully Charge Your Phone?

When it comes to power banks, capacity is a major consideration. It usually taken for granted that the higher the capacity, the better the power bank is. 

With the increasing popularity of e-products such as smartphones and tablets, everyday charging of devices have become a must for modern people. However, we often only look at the appearance and price when they are purchased because we do not know much about the charging industry. Below is a great way to correctly calculate the power capacity.

Here is the formula to calculate how many times a power bank can fully charge your phone:

Power Capacity x 80 % ÷ Cell Phone Battery Capacity = Charging Times

Let’s take ZENDURE power bank as a test example.


Zendure A5 Portable Charger

Approved and used by a number of airlines such as Titan Airways for their pilots to charge iPads, Zendure A5 is the most durable, safest, and trustworthy external battery on the market. Without doubt the amount of charging capacity is our main concern. The capacity of A5 is 16750mAh. According to the formula above, we can know that it can fully charge an iPhone 7 between 5-6 times. What’s more, it has two port outputs, which means we have two ports to charge, using only one plug! It is really convenient when going on a trip.


Zendure A6 Portable Charger

Superior performance, style and cutting-edge compatibility come together in A6. It has a high capacity of up to 20100mAh.The official data shows that it can fully charges your MacBook 1.5 times, iPhone X 5.5 times, Nintendo Switch 2.5 times, and Galaxy S8 4 times. Additionally, it can fast charge iPhone X, iPhone 8, or iPhone 8 Plus up to 50% in just 30 minutes thanks to USB Power Delivery which really helps save time. Nobody can refuse a power bank with a safe quick charge.


With outrageously high charge capacity, four USB ports and QuickCharge 3.0 technology, the A8 was a hit after its release. It is well-known as the monster of quick charging. The A8 QC is one of the fastest charging external batteries on the market for its capacity, thanks to the certified Qualcomm Quick Charge 3.0 Technology. With 26,800 mAh capacity, this monster can easily extend your phone usage 7-9 times, and takes only 10-12 hours to charge using a QC3.0 charger.

Zendure A2

The Zendure A2 power bank is extremely durable, rugged and crush-proof. This charger is designed to take a beating and go with you just about anywhere. It has 6000mAh with a single USB port and a microSD port at the top. There’s a power button with 4 LED lights that lets you know your remaining power. One cool feature is that the Zendure A2 will turn on and off automatically whenever you plug your device in. There’s a bigger version available, but if you’re looking for a strong and rugged power bank that you can take anywhere then this is what you need.

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