What is the best power bank? The best power bank is the Zendure A2, which strikes the perfect balance between price, portability and capacity. Read more about the Zendure A2 and some of the best alternative power banks you can buy in our best power banks chart below. Also see: Best tech to take on holiday 2016.

If you've come here looking for a power bank for use while playing Pokemon Go, we highly recommend the Anker PowerCore 10,000 or Zendure A2 - pocketable, high-capacity power banks that charge your phone fast and are also pretty tough.

Phones get faster every year, but battery life doesn't seem to get any better. If you need to keep your smartphone - or tablet or other USB-powered device - going all day, you need a power bank. We've rounded up the 20 best portable chargers available in the UK in 2016. Also see: How to charge your smartphone or tablet faster

Power banks come in all shapes, weights and capacities, from emergency credit-card-sized devices such as the Onaji Pawa that offers a quick boost to keep you going until you get home, to the ultra-high-capacity LimeFuel Blast Pro L240X, which might charge your phone in excess of 10 times - ideal if you’re going camping or have several devices to charge. Then there are those able to recharge their own battery using solar power, which could mean you never need charge your devices using mains power again. That could save you a few quid on the electricity bill - if you have the patience. Also see: Best MiFi 2016.

Best power banks 2016 UK: Choosing a power bank

Several factors are important when choosing a power bank. One is portability: some of the power banks we review are small and light enough to slip into a pocket; others you’ll notice their presence even when slung in a bag. Pay particular attention to their weight and avoid bulky designs if this is a device you'll carry every day, rather than in certain situations only.

Another factor is capacity. It’s important to note that a power bank will not deliver its full advertised capacity to your device - some of this energy is lost through heat generated and voltage conversion. If a power bank manufacturer doesn’t expressly state otherwise, expect to achieve around 70 percent efficiency at the most. A 10000mAh power bank might therefore deliver 7000mAh of power. Some of the best power banks offer around 90 percent efficiency. Check the specification of your phone or tablet’s battery to estimate how many full charges you can expect from this.

Best power banks 2016 UK: Charging and recharging

The input rating is key when it comes to recharging the power bank - the higher is this figure the more quickly it will charge. You'll usually see a figure in Amps, for instance 1A. You multiply this number by the voltage (5V for USB) to find the rating in Watts. A 1A input can charge at 5W, therefore, but you'd do better to look for a device that can charge at 2A (10W).

Don’t expect to get a USB charger in the box - you can use that which was supplied with your phone or tablet. Do note, however, 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. See also: Expert tips on how to charge your phone

Some power banks support a feature known as passthrough charging, but expect to pay more for this luxury. This allows them to function as a USB hub of sorts, meaning you can simultaneously charge both the power bank itself and your mobile devices, and ensures the power bank is always topped up and ready to go when you need it. Often they will deliver concentrate on charging the attached device first, with any left over power topping up the bank itself, then divert their attention to the power bank once the attached device is full. This is a great feature: you definitely don't want to be getting up in the middle of the night to unplug your now-charged phone in order to fill up a power bank. (If you have only one mains adaptor, consider getting a desktop charger that can simultaneously charge five or six USB devices from a single mains outlet.)

The output rating refers to how quickly a power bank will charge your devices. In most cases you’ll find 1A (5W), 2A (10W) and often even 2.5A (12.5W) outputs, the former intended for smartphones and the latter two for tablets or for fast-charging phones that support the feature. (This is not the same as the Qualcomm Quick Charge feature supported by several flagship phones.) You can use either output to charge any USB device - it will draw only the power it needs. However, you might find some tablets - usually iPads - will refuse to charge from lower-specified outputs. Also see: What is Qualcomm Quick Charge 3.0?

Increasingly power banks feature clever technology which is often referred to as PowerIQ or similar. This allows the power bank to recognise the type of device you have connected for charging and deliver the optimum amount of power for that device. 

If a power bank has several outputs then the maximum total output capacity is key. For example, the LimeFuel Blast Pro L240X has four 2.4A (12W) outputs, but delivers only 4.2A (21W) total output. With four USB devices attached you will find that each charges much more slowly.

Best power banks 2016 UK: Additional features

The best power banks support auto-on and -off functionality, although some support auto-on only and others neither. Auto-on allows them to begin charging your device as soon as you plug it in, and auto-off causes them to switch off when them to switch off when the job is done, meaning no power is unnecessarily wasted. Those that don't support this functionality will have a small power button on their casing somewhere, which is typically also used to light up the LED flashlight (if the power bank has one) or see how much capacity remains.

In most cases you’ll find a series of LEDs used to denote how much capacity remains. This is fine with smaller-capacity power banks, but with larger-capacity models you’ll find the massive jump in capacity between each LED leaves the system rather meaningless. Look out for power banks with LCD displays that are able to tell you the exact capacity remaining, so you’ll never get caught short.

A very common feature in power banks is a built-in LED flashlight. This could come in useful on camping trips, for example, but keep in mind that unless the device is reasonably portable and has an ergonomic design you’re unlikely to use it as a torch. EC Tech’s 6000- and 18000mAh power banks are perhaps the best examples: the smaller-capacity device looks and feels just like a flashlight; the latter is big, heavy and rectangular, making it a bizarre device to use as a torch.

With USB-C gradually creeping on to the market we're beginning to see the connection supported (as both an input and an output) on certain power banks. USB-C will be of use to you, of course, only if you have a USB-C-connected device or intend to buy one in the future. Likewise, some power banks support Apple's Lightning connection, and may charge over Lightning rather than Micro-USB. Given the number of Micro-USB cables we have lying around the home compared to the number of Lightning cables, we know which approach we prefer. Some power banks even have built-in cables, so you don't need to remember to carry one around.

The ideal power bank carefully balances useful capacity with portability, value, fast charging/recharging, multiple outputs and high-end features such as passthrough charging and LCD displays. The closest we’ve found in this regard is the Zendure A2, but we highly recommend all of the devices in this round-up, so you may find one better suited to your budget or one with a design you prefer.

Can a power bank charge your phone in 5 minutes? The truth behind Zap&Go, Simpiz iTron, Pronto & other five-minute power banks

You're joking, right? One day, yes, most probably; right now, no way.

Recently, some of the latest power banks have started hitting the headlines for their apparent ability to charge your phone in five minutes. It sounds preposterous because it is.

What these power banks are actually able to do is refill their own batteries sufficiently within five minutes that they can then fully charge your phone (which is still awesome, but not quite as awesome as how you first read that news). How quickly they can supply that power to your phone depends firstly on how much power they are able to output, and secondly how much power your phone can accept.

As an example, the Simpiz iTron, uses DUBI 1.0 technology to refill its own 9000mAh battery in 18 minutes. If you consider that as 3000mAh per six minutes, it would certainly have enough power to fully charge most phones within five minutes.

When it comes to then transferring that power to your phone, the Simpiz iTron's fastest output is Quick Charge 2.0. This is incredibly fast, but if you have or will have one of the latest devices that support Quick Charge 3.0, such as the Xiaomi Mi 5 or LG G5, it's not actually the fastest charge they are able to accept. There are several examples of Quick Charge 3.0 power banks in our round-up below. Also see: Graphene batteries: what you need to know.

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20 Best power banks 2016 UK

1. Zendure A2

Zendure A2
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 23 March 16
  • RRP: £25.31

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. Note that the Zendure A2 is currently out of stock at Amazon UK, but more are on the way and it should be available within the next week.

Read our Zendure A2 review.

2. Anker PowerCore 10000

Anker PowerCore 10000
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 20 June 16
  • RRP: £20 inc. VAT

Fast, portable, high in capacity and affordable. There are many boxes the Anker PowerCore 10000 power bank does not tick, yet you’d be pushed to find fault with it at £20. A recommended gadget for the upcoming festival- and holiday season.

Read our Anker PowerCore 10000 review.

3. CHJDG UltraCompact Power Bank

CHJDG UltraCompact Power Bank
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 6 July 16
  • RRP: £19.99 inc. VAT

CHJGD is doing what it can to bring some colour to the functional-looking power bank market with the bulldog-inspired UltraCompact Power Bank. It has useful capacity, and it is affordable and easily portable. A great buy if you're in the market for a portable charger you can slip into a pocket.

Read our CHJDG UltraCompact Power Bank review.

4. Xiaomi 10,000mAh Power Bank

Xiaomi 10,000mAh Power Bank
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 13 July 15
  • RRP: £16 inc. VAT

Perfectly balancing portability with capacity, the Xiaomi power bank's feature list and specification is also much bigger than you'd expect. Brilliantly designed, the Xiaomi 10,000mAh Power Bank offers extraordinary value. It's a strong rival to the Zendure A2 in first place in our chart, although the Zendure will prove easier to get hold of in the UK.

Read our Xiaomi 10,000mAh Power Bank review.

5. Flux Card

Flux Card
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 18 August 16
  • RRP: £19.13 + $8.50 shipping to the UK

A fantastic upgrade over the original Flux Charger, the new 4,000mAh Flux takes onboard all our criticisms and comes back fighting. An excellent, truly portable power bank that will get any smartphone user out of a jam.

Read our Flux Card review.

6. Anker PowerCore 20000

Anker PowerCore 20000
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 22 June 16
  • RRP: £27.99 inc. VAT

The Anker PowerCore 20000 offers more power than you’re likely to need and, while it’s smaller and lighter than many at this capacity, fast charging means you won’t need to carry it around longer than necessary. A great buy if you’re going to be away from mains power for several days.

Read our Anker PowerCore 20000 review.

7. Zendure A8 QC

Zendure A8 QC
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 22 August 16
  • RRP: £69.41 inc. VAT

Incredibly well designed with excellent features including passthrough charging and an LCD panel, a tough build and huge amounts of power, that £69.41 asking price doesn't look so high after all. The only thing we can fault Zendure on is the fact its three Zen+ ports can't simultaneously run at full speed. However, the new Quick Charge 3.0 input and output, plus increased capacity are very welcome additions, making this an excellent buy if your power needs are great.

Read our Zendure A8 QC review.

8. RAVPower Ace 22,000mAh External Battery Pack

RAVPower Ace 22,000mAh External Battery Pack
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 6 July 16
  • RRP: £26.99 inc. VAT

Affordable, high in capacity and able to keep three kids entertained at once, the RavPower Ace 22,000mAh is possibly one of the best family power banks. A great buy if you’re planning a long journey away from mains power.

Read our RAVPower Ace 22,000mAh External Battery Pack review.

9. Iceworks Portable Charger

Iceworks Portable Charger
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 24 August 16
  • RRP: £20 inc. VAT

For Micro-USB-connected Android phones and recent-generation iPhones, the Iceworks 5000mAh Portable Charger is a god-send. It’s slim, stylish and easily portable with no need to carry extra cables. At £20 it’s great value, too.

Read our Iceworks Portable Charger review.

10. Tronsmart Presto

Tronsmart Presto
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 6 July 16
  • RRP: £21.99 inc. VAT

The Tronsmart Presto is a good-value power bank with sufficient capacity to charge your phone several times. It places speed of charging above all else, so it’s an ideal portable charger to have to hand (preferably in a bag) when the need arises. With no support for Micro-USB it’s best suited to those with USB-C phones.

Read our Tronsmart Presto review.

11. Anker PowerCore+ 20100 USB-C

Anker PowerCore+ 20100 USB-C
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 1 December 15
  • RRP: £80 inc. VAT

The Anker PowerCore+ 20100 USB-C is a very decent high-capacity power bank for fast-charging all manner of USB-connected devices, including USB-C models such as the Nexus 5X and Nexus 6P - even if you don't have a USB-C smartphone now, chances are you will do at your next upgrade. It's big and heavy, yet remains stylish and easy to use, and currently offers good value. We'd like to see such things as passthrough charging and an LCD screen, but the LED power wheel is the best implementation we've seen, and we appreciate the Anker's ability to recharge itself in just over eight hours.

Read our Anker PowerCore+ 20100 USB-C review.

12. CHJGD Midas

  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 11 July 16
  • RRP: £19.99 inc. VAT

The CHJGD Midas is a premium-looking power bank that comes at a good price, yet doesn’t skimp on performance.

Read our CHJGD Midas review.

13. Griffin Survivor Power Bank

Griffin Survivor Power Bank
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 26 September 16
  • RRP: £49.99 inc. VAT

It might be on the expensive side for a power bank of this capacity, but the tough little Griffin Survivor has a rugged charm. It’s reasonably fast and it’s rainproof, and there are some nice extras such as passthrough charging, auto-on/-off and a lifetime guarantee. If it’s not all about value for money, this may be the power bank for you.

Read our Griffin Survivor Power Bank review.

14. iHarbort Power Bank MS024

iHarbort Power Bank MS024
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 29 June 15
  • RRP: £25

iHarbort's 5000mAh power bank is one of the best deals we've found, offering useful capacity in a stylish and truly pocketable package, support for auto-on/-off and passthrough charging, and the most attractive price tag we've seen. At £12.90 you really cannot go wrong with the iHarbort power bank.

Read our iHarbort Power Bank MS024 review.

15. Anker Astro Mini 3200mAh

Anker Astro Mini 3200mAh
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 9 January 15
  • RRP: £13.99 inc. VAT

Anker's Astro Mini is an extremely useful power bank, both pocketable and pretty, and able to offer your smartphone a full charge away from the mains. At this price we can't fault it. Recommended.

Read our Anker Astro Mini 3200mAh review.

16. Aukey 5000mAh External Battery Charger

Aukey 5000mAh External Battery Charger
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 9 November 15
  • RRP: £10.99 inc. VAT

It's chunkier in design than the similar Anker Astro Mini, and with only 620mAh more effective power capacity, but don't let that put you off. This 5000mAh Aukey power bank is faster to charge your connected phone or tablet, offers easy operation with no physical buttons, and supports passthrough charging. At a penny short of £11, you will have little reason to be disappointed.

Read our Aukey 5000mAh External Battery Charger review.

17. Intocircuit Power Castle PC13000/PC15000

Intocircuit Power Castle PC13000/PC15000
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 22 April 15
  • RRP: £26.99 PC13000

The new Intocircuit Power Castle PC13000 and PC15000 are nicely designed, representing excellent value and fast, easy charging for your phone and tablet away from the mains. The LCD display is a great inclusion at this price. Recommended.

Read our Intocircuit Power Castle PC13000/PC15000 review.

18. EasyAcc 10,000mAh PowerBank (PB100000CF)

EasyAcc 10,000mAh PowerBank (PB100000CF)
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 4 September 15
  • RRP: £12.99

The EasyAcc Power Bank offers astonishing value, and although we've seen power banks with nicer designs, few can match the features it offers at this price. Highly recommended.

Read our EasyAcc 10,000mAh PowerBank (PB100000CF) review.

19. Carved Wood Power Bank

Carved Wood Power Bank
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 2 May 16
  • RRP: $59.99 + $3.99 shipping to the UK

It’s relatively expensive, slow to refill its own battery and comes without any advanced features, but we wouldn’t hesitate to recommend this charming hand-finished wooden power bank on style grounds alone. Just be careful not to let the Carved Wood Power Bank get too hot.

Read our Carved Wood Power Bank review.

20. EasyAcc Rugged Power Bank

EasyAcc Rugged Power Bank
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 11 March 16
  • RRP: £33.99 inc. VAT

If you’re going out in the wild and need a heavy-duty, high-capacity power bank to keep your electronic devices ticking over during your adventure, this EasyAcc is the best rugged power bank we’ve tested. For all other times, however, it’ll be overkill.

Read our EasyAcc Rugged Power Bank review.