Almost every smartphone user gets a little nervous when they only see 10% battery life or less on their screen. No power outlet nearby? Then a power bank is the ultimate resort. We explain what you should pay attention to when purchasing a power bank.
Tip 01: Always welcome
A power bank is an external rechargeable battery. In most cases it concerns a Lithium-Ion battery, occasionally you will also come across a power bank with a Lithium Polymer battery. Usually it is in a nice plastic or metal housing with one or more USB ports so that you can fill up extra energy for your smartphone at any time. A few years ago, these handy helpers were mainly popular with business people who often traveled by train or plane. Also read: The 7 best power banks for your smartphone.
Today, power banks are fully established. Many pupils and students have a copy in their book bag and you also see a lot of people using a power bank on the train or on a festival meadow. Logical, because with intensive use, almost no smartphone makes it to the end of the day. A power bank is therefore always welcome. It gives a lot of people a safe feeling without having to spend a lot of money for it. For less than twenty euros you can already get an entry-level model. Mind you, there is almost never a power adapter in the box. To charge the power bank itself, you can connect it to a USB port on your computer or use the adapter of your smartphone. Keep in mind that it will charge a lot faster via an adapter than via your PC.
Tip 02: Capacity
The power and size (and also the price) of a power bank depends on the capacity of the battery it contains. We express this capacity in milliampere-hours or mAh for short. The higher the number of mAh, the more energy the power bank can store. In order to make the right choice, it is initially good to know what capacity the battery in your smartphone has (see box 'Which battery is in my smartphone?'). If you want a power bank that can fully charge your smartphone battery once, you should therefore choose a power bank with at least the same capacity.
You could basically say that a power bank up to 5,000 mAh is for regular users. Power banks with a capacity of 5,000 to 10,000 mAh are more suitable for intensive users and more than 10,000 mAh are only suitable if you would not have access to electricity for several days or if you want to charge multiple devices at the same time. Also keep in mind that the capacity is a rough indication. Over time, the power bank itself also loses some energy, so that you can fully charge a smartphone with a battery of 2,500 mAh just twice with a power bank of 5,000 mAh.
Tip 03: Small or large?
As soon as you want to buy a power bank, the size also plays a role. A power bank with a capacity of 10,000 mAh or more is often large and heavy. Such a powerhouse gives you a lot of extra energy, but also takes up a lot of space. Just want some extra power for emergencies? Then a compact copy will suffice. There are power banks in credit card format or even in the form of a key ring. The Leitz Powerbank Complete Credit Card is the size of a debit card and fits perfectly in your wallet. It's only a few millimeters thick and even has a built-in Lightning cable for your iPhone. The Firebox Power Pen is also easy to take with you. This aluminum ballpoint pen (also stylus) doubles as a power bank (700 mAh) and is equipped with a built-in Lightning or micro USB cable.
Tip 04: Amperage
Not only the capacity, but also the amperage or current of a power bank is an important measure. On each power bank you can read how much the output of the battery is. This is expressed in amperes or abbreviated in A. Most power banks are between 1 and 3.5 A. Every now and then you come across a copy of 0.5 A, but you better avoid that. The higher the number, the faster your device will charge. Do you not only want to charge a smartphone, but also a tablet? Then definitely choose a power bank with a minimum of 2 A and 6,000 mAh. There are also power banks with multiple USB ports with different outputs: for example, a 1 A USB port for smartphones and a 2 A port for a tablet. With a power bank of 1 A you can theoretically also charge a tablet, but that will be excruciatingly slow.
Which battery is in my smartphone?
Not sure how powerful your smartphone or tablet battery is? Here you see an overview of some popular devices. Note that the capacity is not directly proportional to the useful life. Among other things, the software, processor and screen size are also important when it comes to battery life.
iPhone 6s - 1,715 mAh
iPhone 6s Plus - 2,750 mAh
iPhone 6 - 1,810mAh
iPhone 6 Plus - 2,915 mAh
iPhone 5s - 1,570 mAh
iPhone 5 - 1,440 mAh
iPad Air 2 - 7,340 mAh
iPad Air - 8,827 mAh
iPad mini 4 - 5,124 mAh
Samsung Galaxy S6 edge Plus - 3,000 mAh
Samsung Galaxy S6 edge - 2,600 mAh
Samsung Galaxy S6 - 2,550 mAh
Samsung Galaxy S5 - 2,800 mAh
Samsung Galaxy Tab S2 (9.7 inch) - 5,870 mAh
OnePlus 2 - 3,300mAh
OnePlus One - 3,100mAh
LG G5 - 2,800 mAh
LG G4 - 3,000mAh
LG G3 - 3,000mAh
Google Nexus 6 - 3,220 mAh
Huawei Mate 6 - 2,700 mAh