Top up your phone battery wherever you are, quickly and with the minimum of fuss. We test and rank the best power banks for 2017.
We’ll help you to wade through this mess to find the best power bank for your precise needs.
But there are power banks in our round-up that are technically superior, with LCD screens, faster and mutliple inputs and outputs, support for USB-C, AC outlets, higher capacity, waterproofing and so forth. Some of this stuff you almost certainly don’t need, but if it comes at a good price we bet you’ll want it.
Confusingly for consumers, not all power banks are created equal. The Zendure A2 sitting at the top of our best power banks list is there because it offers a great balance of portability, affordability, capacity and efficiency, and has an ultra-tough design and passthrough charging.
The faster phones become, the less able their batteries seem to be at keeping up. And what good is an amazing phone if you can’t use it out and about? We want a high-end phone that lasts at very least a full working day, and until we get one power banks can provide welcome relief.
It might seem strange to find a power bank at number one in our chart that doesn’t have an LCD screen, doesn’t support USB-C or Lightning, doesn’t have multiple outputs and doesn’t feature Quick Charge 3.0 support. But we stand by our claim that the Zendure A2 is absolutely the best personal power bank on the market. It’s compact. It’s good-looking. It’s fast. It’s super-tough. It’s plug-and-go. It has enough capacity for several charges and it’s great value. A well worthy winner of our best power bank crown.
It has a similar usable capacity to the similarly priced Omnicharge, yet lacks its LCD screen and is much larger and less easily portable. However, this RavPower PowerStation Series 20,100mAh Portable Power Outlet is much easier to get hold of in the UK and even comes with a UK three-pin AC outlet. Both devices are expensive at around £100, but offer insanely fast charging (and recharging) of almost anything you like. A fantastic buy if you can afford it.
Moshi has created one of the most attractive and portable power banks we’ ve seen in the IonSlim 5K – this is one of the few that you really won’ t mind carrying around with you. Our only real gripe is the price: £50 is a lot for a 5,150mAh battery, so you’ ve got to decide how much of a premium you’ re willing to pay for the pared down design.
You might assume all power banks are much the same thing, but you would be wrong. You can get compact power banks that will charge your phone once, slightly larger portable chargers that might offer two or three charges, or high-capacity banks that can charge your phone in excess of 10 times.
Working out how many times a power bank will charge your phone depends on more than the mAh rating on the packaging. No power bank is 100 percent energy-efficient, with every portable charger losing power through voltage conversion and heat generated.
The industry standard for energy efficiency is between 60- and 70 percent, but some of the best can offer 90 percent efficiency.
We’re seeing an increasing number of power banks with support for Quick Charge 4.0 and USB-C, and in some cases these are supported on the input as well as the output, making them as fast to refill as they are to charge your phone. Power banks may offer these in place of or alongside full-size USB, Micro-USB and Lightning ports.
We’re starting to see power banks that feature an AC/DC outlet (a plug socket for non-USB devices) . Unfortunately many offer only a US two-pin plug, so you may need to carry an adaptor.
Another type of power bank builds in solar panels. You might think living in the UK our grey climate would rule out the use of such a device, but even in cloudy conditions these devices can draw some solar power.
Design is important when it comes to choosing a power bank, and some batteries are more compact than others at the same capacity. You can also buy those protected from the elements, but be sure to check whether they are waterproof or simply rainproof.
Nearly all power banks use LEDs to show you how much power remains in the device. This is fine for smaller-capacity devices, but when each LED represents several charges for your phone it can be difficult to see where you are. We favour banks with built-in LCDs.
Passthrough charging is a great feature to have – the ability to charge a connected smartphone at the same time as the device itself.
Auto-on and auto-off is another sought after feature, though sometimes a bank can support this and your phone won’t. It means you can plug in a device and the power bank will begin charging without you pressing any buttons. When charging is complete it will put itself into standby mode to conserve energy.
Some power banks also come with an LED torch, activated by double-pressing the power button.
The input rating is key when it comes to recharging the bank – the higher is this figure the more quickly it will charge. You’ll see a figure in Amps, and you multiply this number by the voltage (5V for USB) to find the rating in Watts.
Don’ t expect to get a USB mains charger in the box – you can use that which was supplied with your phone or tablet. Note that a power bank with a 2A (10W) input will not recharge its own battery any faster than one with a 1A (5W) input when used with an underspecified USB charger.
The reverse is also true when it comes to charging your devices – a phone that supports only a 1A (5W) input won’ t charge faster from a 2A (10W) output.
The output rating refers to how quickly a power bank will charge your devices. In most cases you’ ll find 1A (5W) , 2A (10W) or 2.5A (12.5W) outputs.
You can use any output to charge any USB device – it will draw only the power it needs. However, you might find some tablets will refuse to charge from lower-specified outputs.
Increasingly power banks feature clever technology called PowerIQ or similar. This allows the bank to recognise the type of device you have connected and deliver the optimum amount of power.
