After upgrading from OH3 to OH4 the channel battery-soc of the E3DC powerplant thing has a string unit (1 one). It is no longer formatted in percent.
I this a bug or is an migration for the E3DC binding necessary?
No, binding is fine.
Note there’s a major change in handling units and Percent is such a unit.
Update:
Binding will be updated with standard display of channels autarky, self-consumption and battery-soc with Percent => [e3dc] State pattern with Percent as default for QuantityType:Dimensionless by weymann · Pull Request #15691 · openhab/openhab-addons · GitHub