When looking for a portable charger, you should keep a few factors in mind.
Capacity
There are many factors that may affect the output of a power bank, including its cable, the device being charged, and the charging technique. The mAh measurement for a power bank’s capacity might be deceiving because of this (Qi wireless charging is less efficient). You’ll never be able to use all of the available storage. We do our best to give you an idea of how much each gadget will cost.
Charge Rates and Standards
The wattage (W) of a smartphone’s charger is standard, while the voltage (V) and amperage (A) of a power bank are more common (A). Fortunately, you can just multiply the voltage and amperage to get the watts.
Even if you’re using a high-quality charging cable, you may not be able to obtain the full charge from your smartphone. The Power Delivery (PD) standard is supported by several cellphones, including Apple’s iPhones, and charges at a rate of around 20 W.
Moreover, only a few phones, such as the Galaxy S line from Samsung, offer an additional PD protocol known as PPS (programmable power standard) that can provide up to 25 W of power. Qualcomm’s proprietary Quick Charge (QC) technology is also supported by many smartphones. Even if there are other proprietary fast-charging protocols, most power banks do not support them unless made by the smartphone maker.
Pass-Through
Pass-through functionality is required if you wish to charge your power bank and another device at the same time. Charging through pass-through is possible with the portable chargers described above. These include those from Nimble, GoalZero, Elecjet, Biolite, and Mophie among others.
Additionally, a power bank’s lifetime may be shortened if it cycles on and off too often due of variances in the output of the wall charger and that of the device it is charging. Pass-through may potentially cause portable chargers to overheat, thus we suggest care while utilizing it.
Travel
However, there are two considerations to bear in mind before hopping on a plane with a power bank: The portable charger shall not exceed 100 Wh and must be in your carry-on baggage only (watt-hours).
If your power bank has a capacity more than 27,000 mAh, be sure to verify with the airline before you book your flight. Below that, there should be no issue.