I’m having the same issue, 3 out of 6 devices provide battery status, the 3 others don’t.
Battery status of the plant sensor is not being send as passive data (opposite to the other data), so both active or passive scanning is not being used to get the battery data. Instead, xiaomi-ble gets the battery data by connecting to the device, and asks for the battery state (also known as reading characteristics). I think it does that once a day, not sure.
As we now have active connections, why not retrieve also the firmware version ?
2 Likes
Hello guys, I’m really struggling here. Bought one Plant sensor from Xiaomi and everything is working great, except for the battery information that is nowhere to be found. I’m using Shelly as an active scanner and have power on the flower sensor 3 days ago, using the last firmware on it. On HA I’m using the last version and I cannot find the battery entity neither hidden neither on developer tools. 
It appeared immediately after you add it to HA or do you had to wait 24h to remove / add it again?