You'd lose a lot in efficiency. A power bank designed for this would have 2 cables and 1 or 2 wires, power transfer cables and sense/control wires. My engineeri

You'd lose a lot in efficiency. A power bank designed for this would have 2 cables and 1 or 2 wires, power transfer cables and sense/control wires. My engineering brain says "don't do this it's stupid and I think OP was making a joke I don't get"