This allows us and our advertising providers to show adverts more relevant to you, limit how often you see an advert and build a profile of your interests. Despite the petite dimensions (it sits in the palm of your hand), the imuto has a charging capacity of 20,000 mAh. While the spec isn't as impressive as the imuto, the Juice feels like a different type of product: less a one-box-charges-all power bank, more a use-and-abuse battery to fling around in your backpack. It offers pass-through charging and cleverly, the efficient circuitry prioritizes charging your connected device first and then funnels the extra energy to your IonBank itself at the same time, so you get the optimum run time out of the time you have spent plugged in. It looks metallic, but the case is actually made of plastic polycarbonate, which houses the lightweight lithium-ion polymer battery cells that power it.

Duracell Power Bank 6700 mAh, Portable Charger with USB C Duracell Power Bank 6700 mAh, Portable Charger with USB C

Precharged and ready to use straight away, this is a 10,000 mAh power bank offers around four full smartphone charges. The other power banks I tested tell you their charge level by a light system – four for full, one for somewhere approaching empty, for example.

Qualcomm is a trademark of Qualcomm Incorporated, registered in the United States and other countries. The best idea that Duracell have had with their power banks is their "pay for what you need strategy". Waste electrical products should not be disposed of with household waste – recycle where facilities exist, and check with your local authority for recycling advice.

Duracell USER MANUAL - Duracell

The products or services listed have been selected independently by journalists after hands-on testing or sourcing expert opinions.Join Latest Deals for free and get a hand-picked list of the best deals, delivered straight to your inbox. By rejecting non-essential cookies, Reddit may still use certain cookies to ensure the proper functionality of our platform. The power bank won't fully charge a MacBook, but it’s good enough to lend a 40pc boost in emergency situations – for example, if you need to complete a project and your train breaks down/your cafe of choice inexplicably has no mains plug available/if you’re one of those lucky people who appear to seamlessly run a successful freelance career from the treetops in Bali. That's impressive – most of the power banks I reviewed couldn't handle a laptop at all, let alone offer a full charge. For me, that's plenty: enough juice to provide more than six smartphone charges, or fully charge an iPad Air.

DURACELL 20000 mAh Power Bank (22.5 W, Fast Charging) DURACELL 20000 mAh Power Bank (22.5 W, Fast Charging)

This is a bit of a Catch-22 situation, but it is far easier to charge up a phone when it has between 20 and 80 per cent battery.

It’s much slimmer and lighter than the imuto and Juice (it weighs just 131g), so it’s more of an everyday power bank. The first is that the product is more complicated to use than the Power Station or Belkin – you need to take care to get the right cable in the right slot (an exhaustive instruction manual makes this easy, if somewhat time consuming, to learn). If you need more power on your weekend away, you might need to do something about your screen usage. The IonSlim 10k will charge an iPhone up to four times – enough power for a user and a friend or two. Does it offer pass-through charging (which means you can charge the bank itself, while using it to charge a connected device)?