There are a few things worth thinking about when purchasing a portable charger.
Ability: The capacity of a power bank is measured in milliamp-hours (mAh), but this can be a little misleading because the amount of power you get depends on the cable you use, the device you are charging, and the charging method (The Qi wireless charging is less efficient). You will never get the maximum capacity. We try to provide an estimate of what you will get in terms of device charges.
Charging speeds and standards: The charging speed of devices like smartphones is measured in watts (W), but most power banks indicate voltage (V) and amperage (A). Fortunately, you can calculate the power yourself by simply multiplying the voltage and amperage. Unfortunately, getting that maximum rate also depends on your device, the standards it supports, and the charging cable you use. Many smartphones, including Apple iPhones, support the Power Delivery (PD) standard, which means you can use higher power power banks to recharge the device without problems. Some phones, such as Samsung’s Galaxy S range, support a complementary PD protocol called PPS (Programmable Power Standard) that goes up to 45W. Many phones also support Qualcomm’s proprietary Quick Charge (QC) standard. There are other proprietary fast charging standards as well, but you usually won’t find power banks that support them unless they come from the smartphone manufacturer.
Pass through: If you want to charge your power bank and use it to charge another device simultaneously, you will need pass-through support. The listed Nimble, GoalZero, Biolite, Mophie, Zendure and Shargeek portable chargers support pass-through charging. Anker discontinued the pass-through stand because he discovered that differences between the output of the wall charger and the input of the charging device can cause the power bank to turn on and off quickly and shorten its lifespan. Monoprice also does not support transfer fees. We recommend caution when using the step as it can also cause portable chargers to heat up.
Travel: It is safe to travel with a power bank, but there are two restrictions that you must take into account when boarding a flight: you must have the portable charger in your carry-on luggage (it cannot be checked in) and it must not exceed 100 Wh (watt-hours) . If your power bank has a capacity greater than 27,000 mAh, you should consult with the airline. Below that there shouldn’t be a problem.