A portable power bank is a device that stores electrical energy and can be used to charge other devices such as smartphones, tablets, and laptops.

You can charge your portable power bank using a USB cable and a power source such as a wall outlet, a computer, or a car charger.

The charging time varies depending on the capacity of the power bank and the power source. Generally, it takes 2-6 hours to fully charge a portable power bank.

The number of times you can charge your device depends on the capacity of the power bank and the battery of your device. For example, a 10,000mAh power bank can charge an iPhone X about 2.5 times.

mAh (milliampere-hour) is a measure of the battery capacity, while Wh (watt-hour) is a measure of the energy stored in the battery. To convert mAh to Wh, you need to multiply the mAh by the voltage (V) and divide by 1000. For example, a 10,000mAh power bank with a voltage of 5V has a capacity of 50Wh.

Yes, you can charge some laptops with a portable power bank that has a high enough capacity and the necessary output voltage and connector. However, not all laptops can be charged this way, and it's important to check the compatibility before attempting to do so.

No, not all portable power banks are safe. It's important to choose a power bank from a reputable brand that has been tested and certified by a recognized organization such as UL or ETL. Also, be sure to follow the manufacturer's instructions and do not expose the power bank to extreme temperatures or moisture.

Yes, you can bring a portable power bank on a plane, but there are restrictions on the capacity. In general, power banks with a capacity of less than 100Wh are allowed in carry-on luggage, while power banks with a capacity between 100Wh and 160Wh require approval from the airline.

You should store your portable power bank in a cool, dry place away from direct sunlight and heat sources. It's also a good idea to charge it to about 50% before storing it for an extended period of time.