diff --git a/homeassistant/components/simplisafe/__init__.py b/homeassistant/components/simplisafe/__init__.py
index 3f003284e6f..2e4dfd7c9fa 100644
--- a/homeassistant/components/simplisafe/__init__.py
+++ b/homeassistant/components/simplisafe/__init__.py
@@ -607,6 +607,14 @@ class SimpliSafeEntity(Entity):
             ATTR_SYSTEM_ID: system.system_id,
         }
 
+        self._device_info = {
+            "identifiers": {(DOMAIN, system.system_id)},
+            "manufacturer": "SimpliSafe",
+            "model": system.version,
+            "name": name,
+            "via_device": (DOMAIN, system.serial),
+        }
+
     @property
     def available(self):
         """Return whether the entity is available."""
@@ -620,13 +628,7 @@ class SimpliSafeEntity(Entity):
     @property
     def device_info(self):
         """Return device registry information for this entity."""
-        return {
-            "identifiers": {(DOMAIN, self._system.system_id)},
-            "manufacturer": "SimpliSafe",
-            "model": self._system.version,
-            "name": self._name,
-            "via_device": (DOMAIN, self._system.serial),
-        }
+        return self._device_info
 
     @property
     def device_state_attributes(self):
@@ -730,4 +732,3 @@ class SimpliSafeEntity(Entity):
     @callback
     def async_update_from_websocket_event(self, event):
         """Update the entity with the provided websocket event."""
-        raise NotImplementedError()
diff --git a/homeassistant/components/simplisafe/binary_sensor.py b/homeassistant/components/simplisafe/binary_sensor.py
index ab30deaf70b..ba2f248f9f1 100644
--- a/homeassistant/components/simplisafe/binary_sensor.py
+++ b/homeassistant/components/simplisafe/binary_sensor.py
@@ -48,23 +48,15 @@ async def async_setup_entry(hass, entry, async_add_entities):
     """Set up SimpliSafe binary sensors based on a config entry."""
     simplisafe = hass.data[DOMAIN][DATA_CLIENT][entry.entry_id]
 
-    # Add sensor
-    sensors = [
-        SimpliSafeBinarySensor(simplisafe, system, sensor)
-        for system in simplisafe.systems.values()
-        for sensor in system.sensors.values()
-        if sensor.type in SUPPORTED_SENSOR_TYPES
-    ]
+    sensors = []
+    for system in simplisafe.systems.values():
+        for sensor in system.sensors.values():
+            if sensor.type in SUPPORTED_SENSOR_TYPES:
+                sensors.append(SimpliSafeBinarySensor(simplisafe, system, sensor))
+            if sensor.type in SUPPORTED_BATTERY_SENSOR_TYPES:
+                sensors.append(SimpliSafeSensorBattery(simplisafe, system, sensor))
 
-    # Add low battery status entity for every sensor
-    battery_sensors = [
-        SimpliSafeSensorBattery(simplisafe, system, sensor)
-        for system in simplisafe.systems.values()
-        for sensor in system.sensors.values()
-        if sensor.type in SUPPORTED_BATTERY_SENSOR_TYPES
-    ]
-
-    async_add_entities(sensors + battery_sensors)
+    async_add_entities(sensors)
 
 
 class SimpliSafeBinarySensor(SimpliSafeEntity, BinarySensorEntity):
@@ -108,10 +100,13 @@ class SimpliSafeSensorBattery(SimpliSafeEntity, BinarySensorEntity):
     def __init__(self, simplisafe, system, sensor):
         """Initialize."""
         super().__init__(simplisafe, system, sensor.name, serial=sensor.serial)
-        self._system = system
         self._sensor = sensor
         self._is_low = False
 
+        self._device_info["identifiers"] = {(DOMAIN, sensor.serial)}
+        self._device_info["model"] = SENSOR_MODELS[sensor.type]
+        self._device_info["name"] = sensor.name
+
     @property
     def device_class(self):
         """Return type of sensor."""
@@ -122,15 +117,6 @@ class SimpliSafeSensorBattery(SimpliSafeEntity, BinarySensorEntity):
         """Return unique ID of sensor."""
         return f"{self._sensor.serial}-battery"
 
-    @property
-    def device_info(self):
-        """Return device registry information for this entity."""
-        info = super().device_info
-        info["identifiers"] = {(DOMAIN, self._sensor.serial)}
-        info["model"] = SENSOR_MODELS[self._sensor.type]
-        info["name"] = self._sensor.name
-        return info
-
     @property
     def is_on(self):
         """Return true if the battery is low."""
diff --git a/homeassistant/components/simplisafe/sensor.py b/homeassistant/components/simplisafe/sensor.py
index fcea8b4dab3..fd6f1121af9 100644
--- a/homeassistant/components/simplisafe/sensor.py
+++ b/homeassistant/components/simplisafe/sensor.py
@@ -28,10 +28,13 @@ class SimplisafeFreezeSensor(SimpliSafeEntity):
     def __init__(self, simplisafe, system, sensor):
         """Initialize."""
         super().__init__(simplisafe, system, sensor.name, serial=sensor.serial)
-        self._system = system
         self._sensor = sensor
         self._state = None
 
+        self._device_info["identifiers"] = {(DOMAIN, sensor.serial)}
+        self._device_info["model"] = "Freeze Sensor"
+        self._device_info["name"] = sensor.name
+
     @property
     def device_class(self):
         """Return type of sensor."""
@@ -42,15 +45,6 @@ class SimplisafeFreezeSensor(SimpliSafeEntity):
         """Return unique ID of sensor."""
         return self._sensor.serial
 
-    @property
-    def device_info(self):
-        """Return device registry information for this entity."""
-        info = super().device_info
-        info["identifiers"] = {(DOMAIN, self._sensor.serial)}
-        info["model"] = "Freeze Sensor"
-        info["name"] = self._sensor.name
-        return info
-
     @property
     def unit_of_measurement(self):
         """Return the unit of measurement."""