How to Choose the Best power banks (With Infographic)


Power banks are one of the most used types of charging electronics. There are a lot of different power banks that features lots of different aspects. It’s easy to get confused about what features you should look within a power bank. That’s why Charger Harbor has created our very own guide on what to look for in a great power bank. By looking for these features or at least considering these aspects while you search for a power bank; You will end up purchasing a power bank that delivers exactly what you needed.

What’s a power bank?

First, let’s just go over the simple topic of what is a power bank? A power bank is a device that holds batteries and the purpose of the power bank are to charge devices. What devices does a power bank charge? Any compatible device that uses a USB charging cable to charge can be used with a power bank.

Power banks come in all sorts of sizes that vary with sizes, power capacities, and different charging technologies. They’re a great solution if you find yourself with a low battery on your smartphone throughout the day because a power bank can go with you nearly everywhere.

Now let’s move onto the aspects to focus on when you’re looking to buy a power bank.

1. Capacity

Capacity EN

If there’s one thing that is very different from one power bank to another, it’s the capacity. Capacities within power banks are measured by milliampere-hour. The higher the mAh, the longer the battery will last. This is something to look out for when you’re buying a power bank because you want a high enough capacity that’s going to charge the device that you want to charge your power bank all the way.

If you’re purchasing a power bank for solely charging your smartphone, then we maybe getting a power bank in the 3,000mAh range is the best option. That’s because many smartphones have a battery capacity of at least 2,000mAh. With a 3,000mAh power bank, you’ll be able to charge your smartphone all the way and still have a little more power left over.

Then there are circumstances when you may need a higher capacity power bank because you want to charge your iPad, smartphone and other electronic devices that you think you’ll use a power bank to charge with. This is when going into a higher capacity such as 20,000mAh power banks are the best choices. Higher capacity power banks allow you to not worry about recharging the power bank until a few days after when the power is depleted. Usually, when a power bank is depleted of its power, it’s best to recharge it overnight since you’re not depending on it when you’re sleeping.

We recommend that you start at the 3,000mAh range because a capacity of 3,000mAh is the modern standard of a Mini capacity power bank. Mini pertaining to size and capacity of the power bank. Then go higher from there and see what suit your needs. Figure out just how much power you need through your daily life and match it up along with your power bank.

2. Charging Speed

Charging Speed EN

Power banks also have quite a few charging speeds. Knowing what charging speeds a power bank has is the difference between being extremely dissatisfied with your power bank or having your device well charged.

This is why it’s important to know how to read Output and Input levels on power banks. The Output charging is the charging that is done to the device that you’re charging . The Input charging is the charging being done to the power bank itself, so Input charging, in this case, means recharging speed of the power bank.

Let’s go over how you should choose what charging speeds mean what and what speeds you should look for; But first let’s go over two main terms.

Voltage: The voltage is basically the regulator of the charging process. The voltage is able to keep the Amp Current constant so the speed of charging is constant. The more current there is while charging, the more constant the charging speed will be.

Amperage: The Amperage is the charging speed of the charging process. Higher the current, the faster the power is delivered to the device that you’re charging. However, the Amp is regulated the by the Voltage and may not always be constant if the Voltage of the charger is low. For the Amp current to be constantly fast, there needs to be enough Voltage to support the charging speed.

Now that you know both of the main terms to actually understand what charging entails, let’s move onto charging speeds.

Output charging speeds:

Slow – 5V/1A:

Medium – 5V/2A

Fast – 5V/2.4A

Quick Charge – 9V/3A

This is the standard of Output charging. If an output charger has a 1 Amps of charging current, then you’re going to experience somewhat slow charging, but it’s mostly the Mini power banks that have a charging speed of 1 Amp, so you shouldn’t be too hard on the small power banks. Medium charging rate is at a 2.0 Amp charging current that is quite common for a lot of power banks, this is especially the case if power bank has two ports where one port may have 2A charging and the another port has 1.0A charging; Although the 2.0A rate of charging is actually starting to die out since faster charging rates are beginning to arise.

Then we move onto the higher charging bracket where the 2.4 Amp of charging is actually the latest and fastest type of standard charging that doesn’t require any special charging technology. The 2.4A charging speed is a becoming more of the standard because it heavily boasts a quality of a power bank by providing a charging speed of a wall charger within a power bank. Then there’s Quick Charge charging that pushes into the 3.0 Amps of charging. However, the Quick Charge technology is only available with devices that are compatible with Quick Charge technology and the power bank must have Quick Charge enabled charging ports as well for Quick Charge speeds to actually take effect.

Now that you know what charging speeds you can expect from power banks and know what they mean, you should be well on your way to getting a power bank that charges your devices quickly. Also, you should check if you have a Quick Charge compatible smartphone, and if you do, then you should purchase a power bank that features Quick Charge ports for super-fast charging. iPhones are not compatible with Quick Charge, though.

3. Portability

Size EN

One of the main reasons power banks exist in the first place is because they’re highly portable. That’s why their other name is known to be Portable Chargers because they can charge your device while you’re on the go.

Nearly all power banks are portable in some way, it’s just that some power banks are more portable than others. Portability is actually matched to the capacity of a power bank because when the capacity of a power bank is higher then the battery pack must be bigger; Although that is mostly true, with today’s portable chargers even though the capacity may be quite large, the size of the power bank will be relatively small. So we’re getting to the point of putting high capacities into smaller sizes.

With that said, if you wanted a power bank that would fit into your pocket or basically a small power bank that you’d take with you every day; Then you would choose a Mini power bank that is cylindrical and about 5 inches long. It’s these kind of power banks that offer optimum portability that allows you to freely charge your smartphone without feeling held back. The same goes for Slim power banks, that are about the same size of smartphones.

If you’re going into the higher capacities, then you should expect some size change, but also quite a difference in weight. Let’s give an example of 20,000mAh power bank. 20,000mAh is a lot of power as a power bank that will last you for days but it can still be portable, although not in the same manner that a 3,000mAh power bank would be. Instead, a 20,000 mAh power bank would be alright for on the go purposes but even better for taking it to a location where there isn’t a way wall charger, so you’d use your 20,000mAh power bank. Power banks that are larger aren’t always convenient to use for everyday purposes but they can be great in certain situations.

Know what you’re going to do with your power bank and where you may take it. You want to feel comfortable and confident with the portable charger that you purchase.

4. Ports

Ports EN

Different power banks have different amounts of charging Output ports. Charging ports are very connected to the amount of capacity that a power bank holds. That’s because a power bank with a capacity of 3,000mAh only has one charging port because two devices pulling power from such a low capacity doesn’t make sense since the capacity of the small capacity power bank will deplete very quickly and both devices would be barely charged.

If you wish to charge many devices at the same time freely then we recommend a power bank with many ports. Power banks with many ports can range from having two, three, four and even five ports on some high capacity power banks. These kind of multi-port power banks are also great to use for a charging hub for friends, family, at the office or even strangers in the library that are looking for a harbor to charge their smartphones. You could very well be a charging hero if you give people the power to charge their devices.

Ultimately, how many ports you want will depend on what capacity you need. Perhaps you will find that having too many ports is too much of a hassle and want a lightweight portable charger that is a plug and goes case.

5. Price

Price EN

The price point of power banks is directly related to all the aspects of power banks that we mentioned above but the price of a power bank is still part of what the power bank is and it’s also a vital way to choose a great power bank. With all the aspects mended together and the understanding what a power bank should have, then comes the price of the power bank.

This is where you need to match up the charging speed, capacity, size and the technology that the power bank uses to know for sure that the charger you’re purchasing is indeed worth the price. You should also make sure the power bank is built to standards, meaning that the charger is well built for frequent use so it doesn’t fall apart. So you shouldn’t be paying $20 dollar for a simple Mini power bank because it’s the base of all power banks and should actually have a price of $12. The same goes even for high capacity power banks within the 20,000mAh range. Some high capacity power banks are actually priced absurdly high because some companies may think that people searching for power banks may believe a 20,000mAh capacity is actually worth $80. That’s not true at all.

Even higher capacity power banks are priced low than you’d think from reputable charging electronic companies. At this stage of getting a power bank, things can be a bit hazy and pricing options can be misleading; But that’s why Charger Harbor is here to help you set sail in the right direction so you can get the best power bank that you’re looking for. Just a look at our Power Bank Reviews section to get started on setting sail.


Searching for the correct power bank that you need can be somewhat challenging but by following the guidelines that we’ve mentioned, we’re confident that getting a power bank is actually very easy. Power banks are at a point where they’re very advanced and lots of work is being done to advance them even further because so many people need them. You’re well on your way to getting a great power bank if you’re searching for one.