How to Choose a Powerbank
Things to Consider
A powerbank’s capacity is measured in milliamp hours (mAh). The higher the mAh, the more charge you get out of it before recharging it. A 4,400mAh powerbank can provide up to 160% extra battery life for a standard smartphone, while a 20,000mAH powerbank can provide up to 720%.
In general, the higher the capacity, the bigger and heavier the powerbank.