diff --git a/homeassistant/components/powerwall/sensor.py b/homeassistant/components/powerwall/sensor.py
index b4988133727..f242d2c67e6 100644
--- a/homeassistant/components/powerwall/sensor.py
+++ b/homeassistant/components/powerwall/sensor.py
@@ -297,7 +297,6 @@ class PowerWallBackupReserveSensor(PowerWallEntity, SensorEntity):
     _attr_translation_key = "backup_reserve"
     _attr_state_class = SensorStateClass.MEASUREMENT
     _attr_native_unit_of_measurement = PERCENTAGE
-    _attr_device_class = SensorDeviceClass.BATTERY
 
     @property
     def unique_id(self) -> str:
diff --git a/tests/components/powerwall/test_sensor.py b/tests/components/powerwall/test_sensor.py
index 9b533304fbc..7f23550f522 100644
--- a/tests/components/powerwall/test_sensor.py
+++ b/tests/components/powerwall/test_sensor.py
@@ -118,7 +118,6 @@ async def test_sensors(hass: HomeAssistant, device_registry: dr.DeviceRegistry)
     expected_attributes = {
         "unit_of_measurement": PERCENTAGE,
         "friendly_name": "MySite Backup reserve",
-        "device_class": "battery",
     }
     # Only test for a subset of attributes in case
     # HA changes the implementation and a new one appears