There's much more to a power bank than charging your phone, and you could be missing out on some seriously cool features that will save you time and make life easier. We explain what to look for in a power bank, and round up some of the best examples of portable chargers you can buy today.
The design and capacity of a power bank are probably the two things you're most likely to consider when choosing a power bank. Is this thing going to fit in your pocket, is it going to weigh down your bag, and how many times will it charge your phone? But there is so much more to consider.
Design & capacity
This is not an area that should be overlooked, and not least because you'll likely carry your power bank with you most of the time. Naturally you're going to want something that looks good, but there are other considerations to be made.
Chief among these is size and weight. The higher the capacity of the bank, the more likely it is to be big and heavy, but some power banks do a much better job than others of keeping things compact.
Consider how many times you want to be able to charge your phone before needing to recharge the power bank. The smallest and most portable chargers have around 3000mAh capacity, but given that they typically run at around 65% efficiency this may not even charge your phone once.
In our experience between 6,000- and 7,000mAh is an ideal compromise between portability and charging potential, small and light enough to fit in a pocket and providing two to three charges for your phone. You might find a particularly compact 10,000mAh model also does the job.
If you're going to be away from home longer much higher-capacity models are available, and we'd advise looking at 15,000mAh and above. These will be heavy, however, so don't expect to carry them in a pocket. (Remember that you can't take anything higher than 27,000mAh (100Wh) on a plane without the airline's approval.)
One sought after feature is an LCD screen that gives an exact readout of how much capacity remains (using a four-LED system on higher-capacity banks can be misleading), but you might also want to look for waterproofing and ruggedising, a solar panel that can charge the bank away from home, and integrated LED torches and lanyards. You can even now find power banks that support wireless charging. Note that you may pay extra for these features.
Ports & Performance
Consider not only the connectors themselves - Micro-USB, USB-C, Lightning and now even full-blown AC adaptors - but also the number of those connectors. How many devices do you need to charge at once?.
If your phone supports Quick Charge, look for a power bank that also supports the standard. As a general rule, 5W (5V, 1A) is slow, 10W (5V, 2A) is fast, and anything higher than this is excellent.
Don't be fooled by clever marketing: the claimed intelligent technology that optimises the amount of power delivered to your device is really useful only when you're sharing the bank's maximum output between several connected devices, because your phone will draw only the charge it requires.
Some devices, such as laptops, require more powerful 'USB PD' (power delivery, which can deliver up to 100W) chargers - see our separate guide to laptop power banks.
Remember that speed is important on the output but also the input - most power banks aren't sold with chargers, so if you want to make maximum use of a fast input be sure to pair it with a similarly specced charger.
Remember that eventually your power bank will run dry, and when that happens you'll need to charge it as well as the device you were previously using it to charge. The best power banks support passthrough charging, which means they can be charged at the same time as you any devices connected to their outputs, requiring only one mains power outlet and minimal faffing around with adaptors.
1. Mi Power Bank 2 10000mAh
Now that Xiaomi's power banks are officially available in the UK there is nothing better in terms of value, design and performance.
If you can find it then we recommend the Pro (USB-C) version of this power bank, which has a super-thin 12.58mm design and is clad in tough-feeling yet premium-looking matte-finish aluminium, in rose gold or space grey. It's a great fit in the pocket, with rounded edges that also make it feel great in the hand. And it will deliver around 7,100mAh to your devices, which is good for two- to three full charges of your phone, at a crazy rate - 18W in and out, with passthrough charging.
It looks almost identical, with the same slick aluminium housing. It's a fraction thicker, at 14.1mm, and can also deliver an 18W output, but the input is rated at 15W and the actual output is 6,900mAh.
The 10,000mAh Mi Power Bank 2 costs £24.34 from Amazon, and £22.23 from Chinese GearBest. Amazon also stocks this power bank in 5,000mAh and 20,000mAh capacities, available for £14.24 and £41 respectively.
All three of these support a low-charging mode suitable for fitness trackers and other low-power tech. Simply double-press the power button to activate.
2. Zendure A2
The Zendure A2 leaves a lot of our boxes unticked, and yet it's one of our favourite all-rounders in the power bank market. What gives?
Quite simply, there is no other power bank that hits the same sweet spot of price, portability, capacity, performance and design. It's available now from Amazon for an affordable £26.99.
It's made from a cool-looking and virtually indestructible crushproof PC/ABS composite material with dual-injection moulding and a shock-absorbing central belt, with four LEDs denoting its remaining capacity. Zendure has shown these power banks get run over by cars and still they survive to charge another phone.
Zendure is in the process of updating many of its models with USB-C and Quick Charge support, but even without those things these older models have a lot to offer. A standout feature is their much higher than industry average 80 percent efficiency rating, and they also have a ridiculously long standby time - six months after you forget about this bank in a drawer it will still have just as much power inside.
The A2 is incredibly compact and pocketable at 137g and 93x48x23mm. Zendure has done a great job of cramming in the power here, too, with a claimed capacity of 6,700mAh. You should see around 5,360mAh of that, thanks to the higher efficiency rate, which should be enough for at least two full charges before needing to recharge the bank.
Although it has just the one USB output it's rated at 10.5W, which offers fast charging for all devices. We're pleased to see passthrough charging, allowing you to charge it and a phone from a single power socket, but even on its own a 7.5W input allows you to recharge the bank in just four hours over Micro-USB.
Read our full Zendure A2 review
3. Tronsmart Trim 10,000mAh Power Bank
Tronsmart's Trim is an interesting power bank, shipping with what appears to be a lanyard but actually unclips to reveal a cable that is Micro-USB at one end and a flat USB-A at the other, making it easy to refill the bank wherever you are.
What's missing from the box is a USB-C cable, which is necessary if you want to take advantage of its 18W Power Delivery port. This is on both the input and output, which means recharging the bank will be much faster when you do so over USB-C rather than 10W Micro-USB. You can also charge your device while charging the bank.
It's worth pointing out that the full-size USB port is also capable of delivering 18W to devices that support it, while VoltIQ ensures it delivers the fastest possible charging speed for whatever you've got plugged into it.
You can use both the USB-A and USB-C ports at once, but the device's maximum output is 18W so neither will run at full-speed.
The Tronsmart Trim has a really nice design, rectangular but slim, at 144x70x12mm, and it weighs just 194g. The black casing has a matt finish that feels lovely in the hand (and not at all slippery), while a rose gold metal trim is seen around the edges.
There's 10,000mAh of juice inside the bank, which should equate to around 6,500mAh usable power.
It's available now from Amazon at £22.99, and ships with an 18-month warranty.
4. Anker PowerCore Speed 10000 QC
The PowerCore Speed QC from Anker is a very close third to the Zendure A2 and Mi Pro Power Bank. With a 10,000mAh capacity (expect around 6,500mAh to be available to your device) it's got enough juice to quickly charge a phone several times, yet it's compact enough to fit in a pocket - the perfect combination. Anker claims it's 27 percent smaller than comparable banks at this capacity, and it weighs just 198g.
It's a fairly simple looking black plastic power bank, but it feels well made and, reassuringly, comes from Anker - a brand well known in the power bank world - with an 18-month warranty. In exchange for this minimal design you get a very reasonable price, £27.99/$34.99 from Amazon at the time of writing.
There's just a single input and single output, with four blue LEDs on top to show how much power remains. So it's nothing fancy, but the PowerCore Speed is functional and intuitive in use.
The Speed 10000 QC is an upgraded version of the PowerCore 10000, and you'll notice it has a blue plastic prong inside its full-size USB output to indicate the improved performance. It supports Quick Charge 3.0, Voltage Boost and PowerIQ, and these three performance technologies combined in essence ensure that any connected device is charged in the shortest amount of time possible.
If you don't have a Quick Charge-enabled phone you'll still get 12W from this output, and the input is also fast to refill the bank at 10W. Unfortunately there's no support for passthrough charging, which would have been the icing on the cake.
Also new with this version is a bundled mesh carry case, which is handy for keeping together the power bank and necessary cables.
Read our full Anker PowerCore Speed 10000 QC review
5. Anker PowerCore II 10000 Slim
A variation on the PowerCore Speed at the top of this chart with a longer, slimmer, rectangular body and new PowerIQ 2.0 technology that allows it to offer 18W fast charging from a single chipset, the PowerCore II 10000 Slim is actually a couple of pounds cheaper at £25.99/$35.99 at Amazon at the time of writing.
Like that model it has an efficiency rating around 65 percent, so it's good for charging most Android phones twice and iPhones three times.
There's also a 20,000mAh version, which costs £41.99/$56.99, but bizarrely looks completely different to the Slim. It is not only twice the capacity but has twice the number of LEDs that denote how much power remains, and features an extra full-size USB output.
Only one of these two outputs is an 18W PowerIQ 2.0 port, however, with the second a 12W PowerIQ 1.0 output. This is still 'fast' when compared to the 5W chargers bundled with iPhones and some other smartphones.
One thing we really like about this upgraded model is that the improved performance is also available on the input, which means you can recharge the Slim in just 4 hours.
So it's 'technically' better than the PowerCore Speed, but we prefer the design of the Speed, and sometimes that can be the most important criteria of all. The extra height of this bank makes it feel bigger than the squat model, even though it's also slimmer.
Read our full Anker PowerCore II 10,000 Slim review
6. ZMI PowerPack 10K
We really like this ZMI PowerPack, and it should probably sit a little higher up our chart, but it's brand-new and not easily available in the UK just yet.
In the US you can pick one up from Amazon for $20.99, but in the UK you'll need to import one from China via BangGood at £19.11. (It was actually supplied by GearBest, but it's not in stock there at the moment.)
The PowerPack has a unique textured design that makes it very grippy, either on a desk or in the hand, yet below its matrix of thousands of tiny dots is a high-gloss surface, which creates an aesthetically pleasing overall look.
It feels incredibly compact for a 10,000mAh bank, weighing just 117g and only 12.7mm thick. We also like how fast this thing is, supporting Quick Charge on both input and output, helping us to overlook the lack of passthrough charging, and the fact it has both Micro-USB and USB-C inputs.
Let's hope the ZMI PowerPack becomes more easily available in the UK asap.
7. Iceworks 7000
The Iceworks 7000 is a very similar setup to the Flux Charger below, with a lower price (£19.95 at Amazon) and easier availability, but just the one built-in cable.
The version we're testing is a USB-C model, with that being very much the standard for new Android phones today, but it does rule out iPhone users and those running older Android phones with a Micro-USB connection.
The Iceworks is a fast charger for your phone or tablet, with both input and output rated at 15W. The output is of the USB-C variety too, so you can use your standard phone charger to juice it up in around four hours, and it'll recharge while charging your connected phone.
Perhaps more interestingly, the USB-C input is also an output, so you can actually charge two connected devices at once if required.
The design is good, but while it's just 9mm thick it still feels rather large for a 7000mAh power bank (of which you'll see around 4,550mAh). It's taller and wider than our connected Galaxy S8 at 156x78mm, which makes it feel less comfortable when stashed in a pocket.
But assuming you'll be throwing this charger in a bag it won't weigh you down at 159g, and we like not having to carry separate cables. You don't really need it, but the mesh carry case supplied in the box is a nice touch.
8. Anker PowerCore Lite 10000
Yet another 10,000mAh variation on the Anker PowerCore series is this Lite model. This one is a similar shape to the Slim, but with a textured top surface that aids grip in the hand and more rounded edges. Four LEDs are tucked away on the side and easy to miss.
It's exactly the same price, at £25.99/$33.99 from Amazon, and has the same usable capacity of around 6,500mAh. That's enough for two- to three charges of your phone, depending on the model.
Where this model differs is with its two inputs: one Micro-USB and the other USB-C (you can't use both at once, and it still doesn't support passthrough charging), making it easier to charge up the bank with whatever cable you have to hand (a Micro-USB is supplied in the box along with a cloth carry case). Both are rated at 10W, which is pretty fast.
This is not a PowerIQ 2.0 model like the Slim, which means it isn't able to match the output speed from a single chipset. This power bank's full-size USB output maxes out at 12W, which is still very fast, but it's not Quick Charge fast.
9. QDOS AirBank Qi Wireless PowerBank
One of many such devices now coming on to the power bank market, the 5,000mAh AirBank is able to not only charge a device attached using a USB cable, but it can also wirelessly charge compatible smartphones.
It has an interesting design with 12 rubber suckers (six on each side) to hold your phone in place, which makes it very practical but is easily caught on the lining of your pocket and, let's be honest, looks a little odd. Still, we can't complain it's just another boring black plastic power bank.
We'll see more and more of these wireless power banks coming on to the market, and at £49.99 (buy here) you will almost certainly be able to find cheaper - and faster - examples.
The AirBank supports Qi charging up to 5W, which is painfully slow. Wireless charging has moved on since the days when this was the maximum possible, and many new flagship phones are beginning to follow suit.
If you can't bear to wait so long to charge your phone then there's also a full-size USB output rated at 2.4A, offering 12W charging for a connected phone. You could even charge two devices at once, although the capacity is not sufficient to fully charge more than one.
QDOS' AirBank will work with phones in their cases provided they are not more than 3mm thick, and at up to 6mm distance. Although it says the device must be plugged into a power source for wireless charging to work, we found it would wirelessly charge our phone when running on the battery too.
10. Aukey 20,000mAh USB-C Power Bank
Aukey's 20,000mAh power bank is appealing for three reasons: its price, at £39.99/$39.99 from Amazon, its large capacity, and its number and variety of ports.
You get three full-size USB outputs, as well as a single USB-C. You can also use this USB-C port to recharge the power bank, which is the fastest method, or you can use a Lightning or Micro-USB input (the latter oddly hidden around the corner from the other ports), so it will work with whatever cable you happen to have to hand. For what it's worth a USB-C cable is supplied in the box.
This isn't going to be the fastest power bank for charging multiple devices, however. While the USB-C can output up to 3A (15W), the remaining three outputs must share the same amount between all three. So if you plug in three devices they are each going to charge at a slow 5W. Still, all those ports could prove very convenient if you have multiple devices.
And if you are charging more than one device then you're going to need lots of juice. With a rated capacity of 20,000mAh you can expect around 13,000mAh to be available to your devices. That might charge an iPhone seven times, or a typical Android phone four times.
Once depleted the large battery will take 10 hours to recharge, though you can continue charging attached devices in the meantime.
The trade-off for all this power is size, and this Aukey charger is huge. It's much larger than our phone at 200mm long and 96mm wide, though also reasonably skinny at 14mm. It's as heavy as it looks at 435g, and feels quite bulky.
The design is also rather basic, a matt black plastic slab with a shiny plastic bumper running around the circumference. The Aukey logo is printed on the front and four small LEDs are visible on the side to show how much power remains.
11. Aukey 26,500mAh USB-C Power Bank
Another USB-C power bank from Aukey, this 26,500mAh model has a higher capacity and also supports faster charging with Quick Charge 3.0, but the trade-off is fewer ports and the loss of auto-on and passthrough charging. It's also significantly more expensive at £57.99 on Amazon.
If speed is everything for you, this is the power bank to choose. One of its two full-size USB outputs supports Quick Charge 3.0 (the other is also fast at 12W), while the USB-C input/output operates at 15W. There's also a Micro-USB input for convenience, we guess, but it's slower (10W) and the only cable supplied in the box is the preferable USB-C.
With more power inside this Aukey is understandably heavier at 580g, but more boxy than its sibling with a rectangular design measuring 151x84x29mm. A black mesh carry case is thrown in, but the design is otherwise fairly boring matt black plastic and what feels like with less attention to detail.
Expect to see just over 17,000mAh of power available to charge your devices, so perhaps eight or nine charges for the average iPhone and five to six for a typical Android.
12. Romoss Ace A20 Power Bank
Another dual-input power bank is the A20 from Romoss. This 20,000mAh power bank has both Micro-USB and Lightning inputs, which makes it easier for iPhone users to recharge the bank without having to also carry around a Micro-USB cable.
The A20 was supplied to us from GearBest, a Chinese importer, where it costs £23.16/$29.26. That's actually a very good price for a power bank of this capacity, but we tend to refrain from reviewing power banks available only in China - they are so easily and cheaply available in the UK that it makes little sense to import them.
Available in rose gold or grey, despite its low price the A20 has a fancy aluminium coating that makes it feel pretty cool. But save for the design, Lightning input and capacity (of which around 13,300mAh should be available to your devices), there's nothing particularly exciting about this power bank.
There's no support for passthrough charging, which is on our list of must-haves for high-capacity power banks (especially given this one will take 13 hours to charge over the 10.5W input), and neither is it particularly fast. Though one of the two outputs is rated at 10.5W, the second is just 5W, and if you use both together that 10.5W is shared between the two resulting on slow charging from both.
Still, if needs must, this bank could potentially charge your iPhone seven times. Just be aware that with big capacity comes big weight: the A20 weighs a very noticeable 491g.
13. Flux Charger
We've included the Flux Card power bank in this round-up because it's a great example of an all-in-one power bank, though it's not the easiest device to get hold of in the UK.
Right now it's on offer at $29.95 (£23.45) on the company's website (down from $39.95/£31.28), but if you want one in the UK you should also factor in $9.50 (£7.44) shipping and the fact you may also have to pay Customs charges.
When we say 'all-in-one' power bank we mean one that includes all the necessary cables for charging your device, resulting in a much sleeker overall package. Typically such devices make you choose Micro-USB or Lightning, but this power bank supports both. All that's missing is USB-C.
It's slim, portable and, since we wrote our original Flux Card review the company has updated its device, now clad in durable black or white aluminium rather than plastic, and still incredibly thin at 7.8mm. It weighs a tiny 88g.
It has a 4,000mAh capacity, which is going to be good enough for a full charge for any phone, and it's reasonably speedy with a 7.5W input and 10.5W output. Passthrough charging is supported, which is a nice extra.
In common with nearly every power bank you'll find today Flux offers four LEDs to show how much power remains, and boasts smart technology to recognise your device and deliver an optimum charge.
Read our full Flux Card review
14. Moshi IonSlim 5K
Another model from Moshi, but this time suitable for everyone, is the 143g IonSlim 5K. It's just as expensive as the IonBank 3K, costing £54.95/$54.95 at Amazon, but packs in more power with a 5,150mAh battery. (There's also a 10K model if your pockets are especially deep.)
A lot of what you're paying for here is the design, and the aluminium-clad IonSlim is a crazy 8.5mm thick - that makes it just a fraction thicker than the USB output found at one end.
There's also a USB-C port, which is both input and output. It's fast at 15W, which means charging the power bank itself doesn't take significantly more time than charging your phone, but we'd have been more impressed were it to provide support for passthrough charging.
Other features are reasonably basic, and this is one of few recent power banks we've tested not to support auto-on. You'll need to plug in your device and then press the power button, which just seems like an unnecessary extra step in this day and age.
Learn more in our full Moshi IonSlim 5K review.
Read our full Moshi IonSlim 5K review
15. Zendure A6PD & A8PD
We've concentrated on standard USB power banks in this chart, but that's to ignore an entirely new category of devices that build in USB Power Delivery support. Power Delivery devices can output up to 100W, which means they are technically capable of driving a USB-C-powered laptop or games console.
Power Delivery chargers can be confusing, however, since not all make it clear in their marketing their exact power output, and some are a long way from that magical 100W. This is actually more important than most users will realise, too: a 29W power bank isn't going to charge a laptop that requires 45W.
It's no surprise that Power Delivery banks cost more than standard power banks, and that's why you'll find Zendure's offerings toward the bottom of our chart. Most users will not need to spend this amount on a power bank, but for those who do they make excellent purchases.
The A6PD (reviewed here) is a 20,100mAh power bank with a 45W output, available from Amazon for £69.99/$72.99. If this isn't enough juice then there's also the A8PD, which has a 26,800mAh capacity but slightly lower 40W max output. It's not available on Amazon UK just yet (coming soon), but in the US you'll pay $94.99 (also via Amazon).
Aside from the capacity the two power banks also differ in the number of outputs they offer. While the A6PD offers a single full-size USB output, a USB-C input/output and a Micro-USB input, the A8PD has swaps the Micro-USB port for an additional three full-size USBs. It will charge in just five hours using a 30W USB PD charger.
In other respects the two Zendure power delivery banks offer all the things we expect from Zendure, including the crushproof casing, passthrough charger and higher-than-standard efficiency rating and standby.
Read our full Zendure A6PD review
16. RavPower PowerStation 20,100mAh
This RavPower PowerStation sits at the bottom of our chart not because it's not any good (actually we wouldn't recommend anything here we wouldn't personally own and use ourselves), but because for most users it will be overkill, and probably over budget. The PowerStation is available from Amazon for £89.99/$95.99, and there is plenty here to warrant that somewhat extravagant price.
The PowerStation stands out for its inclusion of an actual plug socket - and not a US or EU two-pin plug that you need to pair with an adaptor, but an actual UK three-pin plug, rated at 65W. These things are hard to come by. (That said, if you need a two-pin version there's also the £119.99/$129.99 RavPower PowerStation 27,000mAh version, reviewed here.)
As well as the plug there's a 19V/1.6A DC jack for significantly faster recharging - despite its huge capacity you can recharge this bank in just four hours, when a comparable bank might take 13 hours over a standard Micro-USB input.
At 69x69x146mm this power bank isn't going to fit in anyone's pocket, but it does come with a hard mesh case and all the necessary attachments (including some carabiner clips). And it does have enough power to fill an iPhone seven times, and most Android phones four or five times.
Now you're probably not want to carry your actual phone charger with you to plug into this thing, but RavPower has you covered here too with a 15W USB-C output and 12W 'iSmart' USB output. Both these ports are pretty fast, if not Quick Charge fast.
This is a reddot award-winning design, and we love the soft-touch rubbery finish and rounded corners that make it feel less unwieldy and prone to damage. A plastic LED strip running around the middle breaks the black, and the small vents top and bottom help with heat dissipation.