Eli5: How does a power bank charge a device until it dies, wouldn’t equilibrium be reached?

Question

Eli5: How does a power bank charge a device until it dies, wouldn’t equilibrium be reached?

In: 551

Answer 1

As long as there is a voltage differential and a clear circuit, current will flow. Your phone doesn’t feed electrons back through the direction they came from, so there’s always a difference in voltage, until the difference is too low to maintain a flow of electrons, aka, the power bank goes flat.