There is a downside to this though. Faster discharging causes increased heat in the battery. The hotter the battery gets, the less efficient it is. So using the faster port could have a noticeable impact on how much charge you get out at the end of the day. Phones,tablets and other small electronics have more or less standardized on 5V USB power, but laptops are different. These larger devices accept 12V power from a supply that converts the high-voltage AC current coming from the wall into something palatable for the delicate electronics inside your beloved lap-warmer. Pros: Very rugged construction and simple operation. We also like the bright LED flashlight for use around camp. mobile phones that use type c ports are rated to 5v on normal charging and 9v on fast charging mode Thanks to its IPX7 rating, this power bank by Outdoor Tech can be submerged in 3ft of water for up to 30 minutes. That makes it well-suited to the most demanding conditions. It also has a built-in 100-lumen torch with three light settings – another useful feature for the great outdoors. The design is compact and relatively lightweight, while the 10,000mAh capacity gives you real-world performance of a little over three full smartphone charges. However, although there are two USB outlet ports, only one of these supports high-speed charging. The Kodiak Plus 2.0 does not have charge-through capability either.

The Einova Ultra Fast Powerbank keeps things simple, compact, and reliable, which is all you want from a laptop power bank you want to travel with. At 6.75 x 4 x 0.63 inches and 0.498kg, it's thin and relatively lightweight. Combine that with its 74Wh power, and you've got a device that keeps things portable for jet-setting creatives and remote working professionals and is TSA-approved. It even has an easy-to-read LCD display to show just how much juice it has left. With USB-C and twin 2.4A USB outputs, the GP Batteries M-series power bank supports the latest devices and offers speedy charging. You can charge up to three devices simultaneously. The 15,000mAh capacity gives a real-world performance of about four to five smartphone charges (though the manufacturer quotes six). It’s very simple and easy to use – a single button with four LED indicator lights and device auto-detection means you can just plug in and go. It is supplied with a 2-in-1 micro-USB and USB-C cable.With a 26,800-mAh capacity, this is the maximum-sized power bank you can take onto a flight. It’s perfect for vacations and even resembles crush-proof luggage. There are four USB-C ports; the left pair can handle up to 100 watts in or out, and the two ports on the right can put out 20 watts each (total maximum simultaneous output is 138 watts). There’s support for PD 3.0, PPS, and QC 3.0 standards. Pros: Slim design, simple to use and good performance. High battery capacity and competitively priced too. The PowerAdd Slim 2 is as basic as power banks get, with just a micro-USB input, a USB-A output and no support for any fast-charging standards. What’s more, it’s slow. The USB-A output is specified as 10W, but in our tests we measured the output at between 7W and 9W depending on the phone. A 15-minute charge only raised the level on our test smartphone by 7%.

The Venture 70 also has a smart charge feature that can identify different devices. It then applies the fastest charging profile possible, without risk of overheating or overcharging. It also allows pass-through charging. That means you can safely charge devices from the power bank even when it’s plugged into the mains. We also liked the built-in 65-lumen LED torch, which has two brightness settings and three strobe modes, including SOS.With an unusual design that features a fold-up wireless charging stand for phones and a charging spot behind it for your wireless earbuds case (if it supports Qi wireless charging), plus a USB-C port to plug in a third device, the Satechi Duo is a handy power bank to have in your bag. It has a 10,000-mAh capacity with LEDs to show how much juice is left. The downside is that it is slow, offering up to 10 watts of wireless charging power for phones (7.5 watts for iPhones), 5 watts for earbuds, and 10 watts from the USB-C port. It takes three hours to refill the battery with an 18-watt charger.