How Powerful Of A Power Bank Do You Need To Safely Charge A Laptop?
Don’t let the big mAh number fool you. The better comparison is watt-hours.
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While most good power banks can theoretically extend your laptop's runtime by providing a small amount of charge, a proper laptop power bank will store enough energy and charge faster than the battery drains. Two values explain the experience you'll have: watt-hours (Wh) for capacity and watts (W) for output. Power banks provide their capacities in milliamp-hours (mAh), but for a proper measure of capacity across devices (especially for a higher-drain device like a laptop), you need to multiply this value by the voltage to get the true amount of energy stored in watt-hours.
Most power banks store energy in lithium-ion cells at about 3.7 volts (V). Watts are equal to volts times amperes, and you must divide the mAh count by 1,000 since 1,000 mAh is one amp. So for example, a 10,000 mAh...
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