Battery level on RFXtrx sensors

I’ve got an RFXtrx433XL 433MHz receiver integrated in Home Assistant, and some temperature/humidity sensors added. All the sensors are added in Home Assistant. But even if the batteries are starting to get old, all the battery level entities are stuck at 100%. Is there anything I can do about this? Not sure if the devices are actually reporting 100% or if something’s up with the integration.

The sensors are all Telldus 433MHz sensors, and are recognized in HA as “Viking 02035,02038” and “Viking 02811”.

Same issue for me: All my RFX Sensors have a battery at 100%. Difficult to follow them