The AC adapter is for this right. The camera displays 100% battery capacity. There are no alarms, which is used a non-original part. The cable outlet is also ideal to use the provided rubber grommet in the battery compartment of the RX10.
Addendum: The RX10 seems to measure the battery voltage at power. After a few images of the battery voltage is subtracted in each case 1%. But even if the camera thinks the "battery" appears to be empty, the adapter works continue.