Help with Wallpanel MQTT Battery Sensor

I´m trying to create a simple MQTT-Battery-sensor for the Wallpanel App from

Is there something missing in my code or is it wrong formatted?

Thanks for help!

This is my code:

  - platform: mqtt
    state_topic: "wallpanel/trekstor/sensor/battery"
    name: "TrekStor Battery Level"
    unit_of_measurement: "%"
    device_class: battery
    value_template: "{{ value }}"

And this is what I get:

I think you need to tell the template it is interpereting json

    value_template: "{{ value_json.value }}"

That worked, thanks a lot!

Merry X-mas everybody!
Sorry I need help again with this thing. I just want to make a sensor that shows me if the device is ac plugged or not.
I tried it by myself but got no result at all. I guess something important is missing…again.

  - platform: mqtt
    state_topic: "wallpanel/huawei/sensor/battery"
    name: "Mediapad AC"
    payload_on: '{"acPlugged":true}'
    payload_off: '{"acPlugged":false}'
    device_class: "plug"
    payload_available: "ON"
    payload_not_available: "OFF"

Well, I got it by myself. Not the best-practice solution I guess, but it works

1.) I used an ordinary sensor, not a binary_sensor:

  - platform: mqtt
    state_topic: "wallpanel/huawei/sensor/battery"
    name: "Mediapad AC"
    value_template: "{{ value_json.acPlugged }}"

2.) I made a sensor template to rename the output

        friendly_name: "Mediapad power"
        value_template: >-
          {% if is_state('sensor.mediapad_ac', 'True') %}
          {% else %}
          {% endif %}

Hi, I had the same issue and solved it like below:

put the code into binary_sensors.yaml

- platform: mqtt
  state_topic: "wallpanel/tablet/sensor/battery"
  name: "Mediapad (plug)"
  value_template: "{{ value_json.acPlugged }}"
  payload_on: true
  payload_off: false
  device_class: plug

ofcourse you have to have additional line in configuration.yaml

binary_sensor: !include binary_sensors.yaml