Tips for buying the best power bank

Most mobile devices have enough autonomy to get you through the day, however, prolonged or demanding use can lead to a quickly discharged battery.

This is precisely why power banks exist, portable batteries dedicated to supplying energy in such a way that they can give that extra energy that mobile phones, tablets, AirPods, smartbands, smartwatches... need.

However, not everyone knows how to choose the power bank that best suits their needs because the market is too broad and, let's face it, sometimes there is so much data and specifications that it only ends up confusing us.

Therefore, in this article we will explain some of the keys when buying a power ban. Let's start!

The importance of capacity and energy efficiency

On the other hand, you should know that the advertised capacity of the brands is not the real capacity of the power bank, that is, it is usually approximately between 60%-70% of this capacity since it depends on the efficiency of the circuit it incorporates, as well as other more complex factors).

So, for example, if a power bank has 10000 mAh capacity then we would actually have between 6000 mAh – 7000 mAh.

This means that not all power banks are equally energy efficient, some will supply more energy to the devices while others a much lower amount.

For example, in the following graph – prepared by the team of PowerBank20– we can see the energy efficiency of some 20000mAh capacity power banks:

These models store an internal energy of 74 watt-hours (Wh) (20000mAh x 3,7V) and all of them are capable of supplying more than 85% of this energy.

Of course, not all models on the market reach these figures, it will depend on the quality of the materials used in its construction.

Connectivity: number and types of USB ports

We all know the "classic" USB port, that is, the USB-A and we are not surprised by the Micro USB: They are the two most widespread types of USB port among the power bank models on the market.

However, now we are experiencing the revolution of USB-C: a single port that aims to “do it all”, that is, acting as an input and output port and, leaving the scope of power banks, allowing the passage of audio, data, video...

Likewise, another fundamental feature today is to check if the power bank ports have fast charging with one of these 2 protocols: Power Delivery y Quick Charge 3.0 (and soon we will know the ultra fast version).

Furthermore, if you choose to buy a high-capacity power bank, between 20000mAh and 30000mAh, we recommend buying one that also incorporates fast charging in its input port because you will save yourself long hours of waiting.

Of course, you should know that fast charging will only work between devices compatible with these protocols (chargers, mobile phones...).

This power bank can comfortably charge several devices at the same time 😎

Finally, we must not forget other types of connections that we can find in a power bank such as DC ports for charging conventional laptops or AC outlets (yes, like the plugs at home!) that incorporate some models of power banks, the most powerful, to charge any type of device with its own charger.

Capacity, size and weight relationship

One of the biggest problems today is the portability of electronic devices: many people carry more than one device and, Adding a power bank means more weight and space occupied in the bag or backpack where it is carried.

For this reason it is essential to think about the use What do you want to give to a power bank:

For example, if you are interested in charging your cell phone and small gadgets, carry a small power bank with you. 5000 mAh y 10000 mAh capacity is a recommended option. Furthermore, thanks to the LiPo batteries, its size has been reduced.

Power bank with LiPo battery [left] vs. Power bank with lithium ion (Li-ion) battery [right]

On the other hand, power banks 20000 mAh or more can be a real headache from the point of view of portability on a daily basis, given that they cannot always be carried easily in a backpack or bag and require - obviously - more available space.