Hi there,
It’s a fair question, You can use something like this device:
https://www.amazon.com/Dpofirs-Wireless-Charging-Receiver-Interface/dp/B0B5M15V5S
HTH
GL 
PJ 
FYI, You be powering the Xiao with the USB-C connection and recharging the Battery connected to the battery pads I would surmise? If so very inefficient , Try a power bank with a solar panel instead.