Say hello to Battery Buddy "It Goes Both Ways - Lithium Charge/Boost Kit" which does both thru a single USB-C port! Plug in a USB power supply and it charges the battery at a fixed 1.2A. Plug in a load and it provides a boosted 5V at 1.2A from the battery. https://www.alpenglowindustries.com/products/it-goes-both-ways-lipo-charge-boost-kit