Thanks to the HomePod version 14.3 update, Apple's new HomePod mini now supports 18W power adapters or battery packs
The HomePod mini ships with a 20W power adapter and originally required at least 20W to function. An update reduces this limit to 18W, which enables a wider range of adapters and battery packs to work.
The 8-Bit reports that Reddit users discovered the change when testing different power adapters. Apple did not disclose the change in the update notes, but if you use a certified 18W USB-C PD power supply or one offering a greater wattage, you'll be able to run your HomePod mini without issue.
As AppleInsider previously covered, you can even connect your HomePod mini to a battery pack to create a portable AirPlay 2 speaker. As long as you have a proper WiFi signal for the HomePod mini to connect through, all functions should work as normal, even under battery power.
The update doesn't affect the power of the original HomePod, as that model requires a direct connection to a power outlet via a plug, rather than a power adapter.