Technical Insight: Do the USB ports bypass the battery in EPS mode?

We all know the brilliant engineering behind these units: when plugged into the wall, the AC outlets physically bypass the internal battery to save your lifecycles (EPS mode).

But what happens to the front USB-A and USB-C ports? Because USB ports strictly require DC voltage, they cannot pass the raw AC grid power straight from the wall to your phone.

Instead, the unit takes the incoming AC grid power, runs it through the internal converter to make it DC, and routes it straight to the front USB board. The internal LiFePO4 battery cells still get to sit happily idle at your maximum charge limit. You can leave your USB-powered smart home hubs or cables plugged in 24/7 without worrying about micro-cycling the main battery.