Battery anxiety is something that affects us all. Whichever smartphone you carry, do you always feel sure it’s going to last the whole day?

There are several solutions to this 21st-century problem, but battery packs are one of the best. A rechargeable battery can be pulled out of your bag when your phone is flagging. And it can also recharge a compatible tablet, camera, portable music player and so on. 

Some chargers can sort two gadgets at the same time and the most powerful can even re-energise a failing laptop.

Portability is crucial, as is how long the charger will last before it needs to be re-juiced. Some chargers have built-in cables so you can slot them straight into your iPhone, for instance. Speed of recharge is also a consideration.

Most chargers have USB-A output sockets, so you can plug in most charging cables. That’s the most familiar socket, also called USB. Some have USB-C output, which is generally faster.

All of them will have an input socket, which is often another size altogether – microUSB in many instances. It’s good to know which because you can ensure you only carry the cables you need. If the input or output are USB-C, charging may be faster in both directions.

One last thing: some of the latest phones and in-ear headphones can be recharged wirelessly and there are portable chargers which can recharge wirelessly, too. But note that wireless charging, though tremendously convenient, is slower than a wired charge. Still, some of the newest smartphones, like the Samsung Galaxy S10 and Huawei P30 Pro, have two-way wireless charging, so if your friend has one of those and your phone is wireless-compatible, you just put the two phones back to back to share the power from one to the other.

A very rough guide to charging capabilities is that a 2500mAh battery will recharge a smartphone fully once, 500mAh twice and so on.

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Moshi porto Q 5K: £79.95, Moshi

Battery size: 5,000mAh​
Output connections: USB-A, wireless charging
Input connection: USB-C

Moshi makes a big range of beautifully designed gadgets from headphones to smartphone cases, adapters to elegant cables, even. This battery is especially versatile because along with a USB-A socket so you can plug in most gadgets, it also has a wireless charging pad so, if you have a phone that recharges wirelessly, just placing it on the pad starts the charging process. The soft material is pleasing to the touch and a subtle silicone ring ensures the phone doesn’t slide off.

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Belkin valet charger: £89.99, Belkin

Battery size: 6,700mAh​
Output connections: USB-A, Apple Watch
Input connection: microUSB

If you have an Apple Watch, this is a great portable charger because as well as the USB socket which will charge whatever you plug into it, there’s an Apple Watch charging puck built in which senses automatically when you put the watch in place. You can charge both your phone, say, and your watch at the same time. Despite this, it’s a reasonably small size and its aluminium case looks sumptuous and feels good to the touch. A row of lights helpfully tells you how much charge is left in the battery. Note that the watch charger is only for the Apple Watch which charges in a different way from other wireless-chargeable products.

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Anker powercore+ 26800: £89.99, Amazon

Battery size: 26,800mAh​
Output connections: 2 x USB-A, USB-C​
Input connection: USB-C

This is a powerful and effective charger. So powerful, you can charge a laptop like a MacBook from it. There are two USB-A outputs so you can charge two phones at once, for instance. One of the outputs is more powerful so it can charge a tablet. The USB-C connector is used both for charging the expansive battery and to charge a USB-C device. Note that although it comes with a USB-C to USB-C cable, there’s no USB-C charger supplied (though Anker makes a good-looking one called the Atom, £39.99).

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Mophie powerstation plus 10000 universal battery with Lightning connector: £89.95, Apple

Battery size: 10,000mAh​
Output connections: USB-A, Lightning cable integrated

Mophie’s batteries are stylishly designed and well-built: this one has a pleasingly tactile fabric finish. This model is aimed at iPhone owners because not only does it have an Apple Lightning cable built in, you recharge it using a Lightning cable, too. So, if you don’t have an iPhone then you may not have a Lightning cable to charge it. However, you can also recharge the battery by placing it on a wireless charging pad (though this only applies to the Mophie itself: your phone or other gadget have to be charged by cable). There’s also the USB-A output for other phones and gadgets.

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Poweradd QI wireless portable charger: £21.99, Power Add

Battery size: 10,000mAh​
Output connections: USB-A, USB-C, wireless charging
Input connection: USB-C

The Poweradd has a lot going for it, not least its price which, for a wireless power bank is highly competitive. Charging wirelessly is certainly slow but very convenient. And the addition of USB-A and two USB-C ports makes it very versatile. You charge the battery in one of the two USB-C connectors, and the other one charges in both directions. The 10,000mAh capacity is big, though the battery is still reasonably light. Further added value comes from the inclusion of a Lightning cable and USB-C to USB-C cable.

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Moshi IonBank 3K: £69.95, Moshi

Battery size: 3,200mAh​
Output connections: Lightning cable integrated
Input connection: USB-A

This is among the most pocketable of portable chargers, not to mention convenient and attractive. Two cables are built in: one a Lightning cable to recharge an iPhone and the other a USB cable to recharge the IonBank. The cable folds into place under a vegan leather cover. This closes over the device and is held there with just the right firmness by magnets. You can charge both the charger and your iPhone at the same time. Because it’s small, there’s only enough for one charge of an iPhone, or a little more depending on the model. Choose from black and oxblood red finishes.

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Cygnett 10K wireless QI portable power bank: £69.95, Cygnett

Battery size: 10,000mAh​
Output connections: 2 x USB-A​
Input connection: microUSB

Cygnett’s chargers range from light and portable to bigger and more capable. Here, the twin USB-A sockets mean you can charge two phones, say, at the same time, and a wireless charging spot offers the added convenience of not needing to plug cables in for compatible phones. It’s smart enough to know that a Samsung phone can charge at a different wattage from an iPhone, for instance. An easily visible indicator shows the battery charge remaining as a percentage so you know exactly how much juice is left.

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Mophie powerstation USB-C XXL universal battery: £119.95, Apple

Battery size: 19,500mAh​
Output connections: USB-A, USB-C​
Input connection: USB-C

Enough to charge a MacBook Pro or to fast-charge two gadgets at once, the powerstation is very impressive. The USB-C socket charges a compatible laptop but if you want to charge it from a laptop, pressing a button reverses the direction of charge. It feels good in its fabric cover and it’s smart enough so that if you are charging a device and the battery at the same time, it knows to charge the battery first. It’s not light but it’s highly capable.

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Duracell powerbank 6700: £19.99, Amazon

Battery size: 6,700mAh​
Output connections: USB-A​
Input connection: microUSB

Instantly recognisable thanks to being designed like a regular Duracell battery, this is effective at charging a phone three times but doesn’t take up much space. It recharges by microUSB and a four-LED system tells you how much power is left. You can charge a gadget from it while the Powerbank restores itself from the mains. It charges your gadgets fast and is pretty quick to recharge itself. It is well-built and effective, though to be honest, you may just want to buy it because it looks good.

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Cygnett ChargeUp pro 27K: £149.95, Cygnett

Battery size: 27,000mAh​
Output connections; 2x USB-C, USB-A​
Input connection: USB-C

This is a powerful battery which can recharge, from flat to 100 per cent, a laptop as big as an Apple MacBook Pro. Of course, it also works with the smallest smartphone. There are three outputs, two USB-C and one USB-A, so you can charge three gizmos at the same time. Although it is powerful, surge protection is built in to keep your technology safe. It’s big – you will always know whether you’ve packed it or not from the weight. It’s compatible with Qualcomm QC3.0 technology, which just means that compatible gadgets can charge especially fast from USB-C. And the capacity means it is enough to charge a phone up to 10 times.

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Cygnett 6000mAH USB-C power bank: £49.95, Cygnett

Battery size: 27,000 mAh
Output connections: USB-C, USB-A
Input connection: microUSB, USB-C

This is a smaller version of the other Cygnetts here but it still has the 1-100 digital charge indicator and the soft-rubber finish. The USB-C input means you can recharge the battery fast and both USB-C and USB-A outputs can be used at the same time, and are both fast. This charger is a good balance between big power, medium price and small size. It’s just light enough to carry with you all the time for complete peace of mind. Choose from utilitarian black or quiet but appealing teal finishes.

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The verdict: portable chargers

Moshi porto Q 5K wins for standout design and build quality, it’s versatile as well as good-looking. Cygnett is the big brand here, with its ChargeUp Pro 27K offering remarkable amounts of power. For Apple Watch users, the Belkin valet is a near-essential travel accessory.

IndyBest product reviews are unbiased, independent advice you can trust. On some occasions, we earn revenue if you click the links and buy the products, but we never allow this to bias our coverage. The reviews are compiled through a mix of expert opinion and real-world testing.

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