Given the fact that the average smartphone battery lasts around 1-2 days at regular use, power banks have become an essential accessory. As they extend the smartphone usage time by multiple days, they enable people to remain connected even when a power outlet is not available.
As they increased in popularity, ever more power bank models reached the market, to the point that it became difficult to choose the best option. At Power Bank Expert, our mission is to help you navigate through the plethora of options available, in order to be able to have all the information that will allow you to know how to choose the best power bank for your device.
Before making a decision important factors such as capacity, price, size or charging ports should be carefully considered. We’ll tackle the most important of these aspects below.
Power bank capacity
mAh (milliamp hours)
Arguably, the most important characteristic of a power bank is it’s charging capacity. This is measured in mAh (milliamp hours) and it reflects its electrical storage ability. In this sense, mAh is used to describe the total amount of energy a battery can store during a certain time. The higher the mAh, the more energy a power bank can store, and the more times it can recharge your device.
Some of the most common power banks range anywhere from 5000 mAh to 20000 mAh. But as technology improves, power banks will be able to pack more and more energy, going toward 50000 mAh and beyond.
Wh represents the amount of power that a portable charger can supply before needing a recharge, and it is another unit to express the capacity of power banks.
However, cell phones and other portable devices are rated in mAh. Thus, it important to know how to calculate the Wh of your power bank, which is the result of multiplying the nominal output voltage (3.7 V) by the current dissipated by hour (mAh). For example, the capacity in Wh of a 5000 mAh power bank is 3.7 V * 5000 mAh = 18.5 Wh. A common misconception is to think that the voltage of a power bank is 5 V due to the fact that cellphones charge at this rate, when in fact, lithium.ion batteries have been designed to operate at 3.7 V.
Besides charging capacity, the price is maybe one of the most important aspects that people take into consideration when deciding to buy a power bank. Although it’s definitely an important factor, it can be deceiving if the other aspects mentioned on this page are not also considered. A cheap power bank might not necessarily have poor built quality, but it may lack in some key features such as extra charging ports, it might be heavy and bulky or it may have a low charging capacity.