A power supply, the thing that gets plugged into AC mains power and outputs some sort of DC (usually USB now) to power electronics is not a “charger”. It (usually) doesn’t know anything about charging batteries, and connecting its output directly to a Li-ion battery would lead to an explosion. The charger is integrated into the device receiving that power.

“Portable battery” is a terrible term to describe a USB powerbank. Thousands of battery types are portable, but don’t have USB ports or output exactly the right voltage. Some powerbanks are sold without batteries.