batteries.yaml

### Black Panther ###
  black_panther_battery:
    entity_id: device_tracker.ozone
    value_template: "{{ (states.device_tracker.ozone.attributes|default).battery_level|default|int('unknown') }}"
    unit_of_measurement: '%'
    icon_template: >-
      {% set battery_state = states('sensor.black_panther_battery_state')|lower %}
      {% set battery_level = states('sensor.black_panther_battery_level')|int('unknown') %}
      {% set battery_round = (battery_level|int / 10)|int * 10 %}

      {% if battery_level == 'unknown' %}
        mdi:battery-unknown
      {% elif battery_state == 'charging' %}
        {% if battery_round < 20 %}
          {% set battery_round = 20 %}
        {% elif battery_round == 50 %}
          {% set battery_round = 60 %}
        {% elif battery_round == 70 %}
          {% set battery_round = 80 %}
        {% endif %}

        mdi:battery-charging-{{ battery_round }}
      {% else %}
        {% if battery_round >= 100 %}
          mdi:battery
        {% elif battery_round > 0 %}
          mdi:battery-{{ battery_round }}
        {% else %}
          mdi:battery-alert
        {% endif %}
      {% endif %}
A