Is it possible to see battery statuses in HomeKit as I didn't find them? If not, any plan to add them?
It does. Aqara Smart Radiator Thermostat E1
When I look at my Tado devices using the Apple Home app I don't see any battery level information. When I look at other devices such as my Hue dimmer switches, I do. Same thing when using the Eve app, which often shows more Homekit info than Apple's own app.
But don't worry, Tado will send you an email if one of your devices is running low on battery power. 😀
As far as I see. Only status (heating/off), temperature current, humidity and target temperature are pushed towards HomeKit which is pity.