How to buy the best power bank or charger for you
Go up slightly in size and weight to one of the newer slimline, mid-capacity models, and you can expect a 10,000mAh capacity – enough to charge a Samsung Galaxy S10 almost three times over or charge two devices via two ports and still have a little charge remaining. One of these should set you back in the region of £15 to £25.
The biggest (and heaviest) power banks will give you 20,000mAh or more capacity, which is enough to cover a small family’s smartphones over a weekend away or recharge a Nintendo Switch three times. It will, however, weigh down your bag and cost you twice as much as a smaller power bank – think £25 to £35. You might not want to lug one around all day, every day.
What else should I look out for?
You should also keep an eye on the ports provided, the output and support for different quick-charge standards. As far as ports go, most devices will have one micro-USB port for charging the power bank, plus one or more USB Type-A ports for charging any connected devices. However, many models now sport a USB Type-C port, often both for getting charge into the power bank and sending it out to the device you want to charge.
Now things get tricky. The higher the output of your USB ports, the faster the connected device will charge – with one proviso: the device has to be able to take and work with that level of charge. Your basic USB 2 port is designed to output 5V/500mA, while a USB 3.1 port will output 5V/900mA. However, devices with a USB Type-A connector that supports the USB BC 1.2 standard push that upwards to 5V/1.5A, which should work with just about any device released within the last few years. Meanwhile, USB-C connectors can go even further – up to 5V/3A.
Samsung, meanwhile, has its own charging standards (Adaptive Fast Charging), as does MediaTek (Pump Express), Huawei (SuperCharge) and OnePlus (Dash Charge). The big hope is that the open USB-PD standard, based on USB Type-C with 14.5V/2A, may eventually become a simple, common standard. It’s already used in many high-end laptops, plus all iPhones from the iPhone 8 onwards and Google’s Pixel phones.
Is it worth paying extra for a fast charging standard?
Up to a point. If a power bank has a high output (4.8A, say) and will work with a high-output (2A) charger, it’s going to charge your devices and recharge itself pretty quickly anyway. However, if you have, for instance, an existing Quick Charge 3 charger and devices that work with Quick Charge 3, it makes sense to have a Quick Charge 3 power bank – you can charge it faster and then use that energy to charge your smartphone at speed.