diff --git a/README.md b/README.md
index 4d63a66..6711ca6 100644
--- a/README.md
+++ b/README.md
@@ -43,6 +43,8 @@ sensor:
   - platform: airthings_wave
     scan_interval: 120
     elevation: 998
+    voltage_100: 3.2
+    voltage_0: 2.2
 ```
 ### Optional Configuration Variables
 
@@ -58,20 +60,28 @@ sensor:
 
   (float)(Optional) The current elevation in meters. Used to correct the pressure sensor to sea level conditions.
 
+**voltage_100**
+
+  (float)(Optional) The voltage for 100% battery, calculated linearly between voltage_0 and voltage_100 (on supported device), default is 3.2
+
+**voltage_0**
+
+  (float)(Optional) The voltage for 0% battery, calculated linearly between voltage_0 and voltage_100 (on supported device), default is 2.2
 
 ## Limitations
 
-It may be possible that the Wave must be connected to the official app at least
-once before you can use this program, so you will probably not get around
-registering an account with Airthings.
+Users has reported that it is possible to get data without first registering with the official app, 
+so it should be possible to use the sensor with this integration without registering.
 
 The radon level history stored on the Wave itself cannot be accessed
 with this component. To get around this, it connects regularly to the radon
 detector.
 
-Make sure you install the latest firmware on the device using the official app
+It might be beneficial to install the latest firmware on the device using the official app
 first.
 
+Battery level only works for the Airthings wave pluss device. 
+
 ## Known Issues
 
 * Not yet able to specify the `monitored_conditions` configuration
diff --git a/custom_components/airthings_wave/airthings.py b/custom_components/airthings_wave/airthings.py
index 98ca30f..693ac9b 100644
--- a/custom_components/airthings_wave/airthings.py
+++ b/custom_components/airthings_wave/airthings.py
@@ -12,6 +12,7 @@
 _LOGGER = logging.getLogger(__name__)
 
 # Use full UUID since we do not use UUID from bluepy.btle
+CHAR_UUID_CCCD   = btle.UUID('2902') # Client Characteristic Configuration Descriptor (CCCD)
 CHAR_UUID_MANUFACTURER_NAME = UUID('00002a29-0000-1000-8000-00805f9b34fb')
 CHAR_UUID_SERIAL_NUMBER_STRING = UUID('00002a25-0000-1000-8000-00805f9b34fb')
 CHAR_UUID_MODEL_NUMBER_STRING = UUID('00002a24-0000-1000-8000-00805f9b34fb')
@@ -25,6 +26,7 @@
 CHAR_UUID_WAVE_PLUS_DATA = UUID('b42e2a68-ade7-11e4-89d3-123b93f75cba')
 CHAR_UUID_WAVE_2_DATA = UUID('b42e4dcc-ade7-11e4-89d3-123b93f75cba')
 CHAR_UUID_WAVEMINI_DATA = UUID('b42e3b98-ade7-11e4-89d3-123b93f75cba')
+COMMAND_UUID = UUID('b42e2d06-ade7-11e4-89d3-123b93f75cba') # "Access Control Point" Characteristic
 
 Characteristic = namedtuple('Characteristic', ['uuid', 'name', 'format'])
 
@@ -48,7 +50,8 @@ def __str__(self):
 
 sensors_characteristics_uuid = [CHAR_UUID_DATETIME, CHAR_UUID_TEMPERATURE, CHAR_UUID_HUMIDITY, CHAR_UUID_RADON_1DAYAVG,
                                 CHAR_UUID_RADON_LONG_TERM_AVG, CHAR_UUID_ILLUMINANCE_ACCELEROMETER,
-                                CHAR_UUID_WAVE_PLUS_DATA,CHAR_UUID_WAVE_2_DATA,CHAR_UUID_WAVEMINI_DATA]
+                                CHAR_UUID_WAVE_PLUS_DATA,CHAR_UUID_WAVE_2_DATA,CHAR_UUID_WAVEMINI_DATA,
+                                COMMAND_UUID]
 
 sensors_characteristics_uuid_str = [str(x) for x in sensors_characteristics_uuid]
 
@@ -127,6 +130,47 @@ def decode_data(self, raw_data):
         return data
 
 
+class CommandDecode:
+    def __init__(self, name, format_type, cmd):
+        self.name = name
+        self.format_type = format_type
+        self.cmd = cmd
+
+    def decode_data(self, raw_data):
+        if raw_data is None:
+            return {}
+        cmd = raw_data[0:1]
+        if cmd != self.cmd:
+            _LOGGER.warning("Result for Wrong command received, expected {} got {}".format(self.cmd.hex(), cmd.hex()))
+            return {}
+        
+        if len(raw_data[2:]) != struct.calcsize(self.format_type):
+            _LOGGER.debug("Wrong length data received ({}) verses expected ({})".format(len(cmd), struct.calcsize(self.format_type)))
+            return {}
+        val = struct.unpack(
+            self.format_type,
+            raw_data[2:])
+        res = {}
+        res['illuminance'] = val[2]
+        #res['measurement_periods'] =  val[5]
+        res['battery'] = val[17] / 1000.0
+
+        return res
+
+
+class MyDelegate(btle.DefaultDelegate):
+    def __init__(self):
+        btle.DefaultDelegate.__init__(self)
+        # ... initialise here
+        self.data = None
+
+    def handleNotification(self, cHandle, data):
+        if self.data is None:
+            self.data = data
+        else:
+            self.data = self.data + data
+
+
 sensor_decoders = {str(CHAR_UUID_WAVE_PLUS_DATA):WavePlussDecode(name="Pluss", format_type='BBBBHHHHHHHH', scale=0),
                    str(CHAR_UUID_DATETIME):WaveDecodeDate(name="date_time", format_type='HBBBBB', scale=0),
                    str(CHAR_UUID_HUMIDITY):BaseDecode(name="humidity", format_type='H', scale=1.0/100.0),
@@ -137,6 +181,8 @@ def decode_data(self, raw_data):
                    str(CHAR_UUID_WAVE_2_DATA):Wave2Decode(name="Wave2", format_type='<4B8H', scale=1.0),
                    str(CHAR_UUID_WAVEMINI_DATA):WaveMiniDecode(name="WaveMini", format_type='<HHHHHHLL', scale=1.0),}
 
+command_decoders = {str(COMMAND_UUID):CommandDecode(name="Battery", format_type='<L12B6H', cmd=struct.pack('<B', 0x6d))}
+
 
 class AirthingsWaveDetect:
     def __init__(self, scan_interval, mac=None):
@@ -158,7 +204,7 @@ def _parse_serial_number(self, manufacturer_data):
 
     def find_devices(self, scans=50, timeout=0.1):
         # Search for devices, scan for BLE devices scans times for timeout seconds
-        # Get manufacturer data and try to match match it to airthings ID.
+        # Get manufacturer data and try to match it to airthings ID.
         scanner = btle.Scanner()
         for _count in range(scans):
             advertisements = scanner.scan(timeout)
@@ -178,6 +224,8 @@ def connect(self, mac, retries=10):
             tries += 1
             try:
                 self._dev = btle.Peripheral(mac.lower())
+                self.delgate = MyDelegate()
+                self._dev.withDelegate( self.delgate )
                 break
             except Exception as e:
                 print(e)
@@ -238,15 +286,34 @@ def get_sensor_data(self):
                 if self._dev is not None:
                     try:
                         for characteristic in characteristics:
+                            sensor_data = None
                             if str(characteristic.uuid) in sensor_decoders:
                                 char = self._dev.getCharacteristics(uuid=characteristic.uuid)[0]
                                 data = char.read()
                                 sensor_data = sensor_decoders[str(characteristic.uuid)].decode_data(data)
                                 _LOGGER.debug("{} Got sensordata {}".format(mac, sensor_data))
+                                
+                            if str(characteristic.uuid) in command_decoders:
+                                self.delgate.data = None # Clear the delegate so it is ready for new data.
+                                char = self._dev.getCharacteristics(uuid=characteristic.uuid)[0]
+                                # Do these steps to get notification to work, I do not know how it works, this link should explain it
+                                # https://devzone.nordicsemi.com/guides/short-range-guides/b/bluetooth-low-energy/posts/ble-characteristics-a-beginners-tutorial
+                                desc, = char.getDescriptors(forUUID=CHAR_UUID_CCCD)
+                                desc.write(struct.pack('<H', 1), True)
+                                char.write(command_decoders[str(characteristic.uuid)].cmd)
+                                for i in range(3):
+                                    if self._dev.waitForNotifications(0.1):
+                                        _LOGGER.debug("Received notification, total data received len {}".format(len(self.delgate.data)))
+                                
+                                sensor_data = command_decoders[str(characteristic.uuid)].decode_data(self.delgate.data)
+                                _LOGGER.debug("{} Got cmddata {}".format(mac, sensor_data))
+
+                            if sensor_data is not None:
                                 if self.sensordata.get(mac) is None:
                                     self.sensordata[mac] = sensor_data
                                 else:
                                     self.sensordata[mac].update(sensor_data)
+
                     except btle.BTLEDisconnectError:
                         _LOGGER.exception("Disconnected")
                         self._dev = None
diff --git a/custom_components/airthings_wave/manifest.json b/custom_components/airthings_wave/manifest.json
index b4fd173..6aee1c3 100644
--- a/custom_components/airthings_wave/manifest.json
+++ b/custom_components/airthings_wave/manifest.json
@@ -1,7 +1,7 @@
 {
   "domain": "airthings_wave",
   "name": "Airthings Wave",
-  "version": "3.0.5",
+  "version": "3.1.0",
   "documentation": "https://github.com/custom-components/sensor.airthings_wave/",
   "issue_tracker": "https://github.com/custom-components/sensor.airthings_wave/issues",
   "dependencies": [],
diff --git a/custom_components/airthings_wave/sensor.py b/custom_components/airthings_wave/sensor.py
index a35ec95..6785e06 100644
--- a/custom_components/airthings_wave/sensor.py
+++ b/custom_components/airthings_wave/sensor.py
@@ -36,6 +36,9 @@
                                  DEVICE_CLASS_TEMPERATURE,
                                  DEVICE_CLASS_PRESSURE,
                                  DEVICE_CLASS_TIMESTAMP,
+                                 DEVICE_CLASS_BATTERY,
+                                 ATTR_VOLTAGE,
+                                 DEVICE_CLASS_VOLTAGE,
                                  EVENT_HOMEASSISTANT_STOP, ILLUMINANCE,
                                  STATE_UNKNOWN)
 
@@ -84,10 +87,15 @@
 
 DOMAIN = 'airthings'
 
+CONF_VOLTAGE_100 = "voltage_100"
+CONF_VOLTAGE_0 = "voltage_0"
+
 PLATFORM_SCHEMA = PLATFORM_SCHEMA.extend({
     vol.Optional(CONF_MAC, default=''): cv.string,
     vol.Optional(CONF_SCAN_INTERVAL, default=SCAN_INTERVAL): cv.time_period,
-    vol.Optional(CONF_ELEVATION, default=0): vol.Any(vol.Coerce(float), None)
+    vol.Optional(CONF_ELEVATION, default=0): vol.Any(vol.Coerce(float), None),
+    vol.Optional(CONF_VOLTAGE_100, default=3.2): vol.Any(vol.Coerce(float), None),
+    vol.Optional(CONF_VOLTAGE_0, default=2.2): vol.Any(vol.Coerce(float), None),
 })
 
 
@@ -148,7 +156,24 @@ def get_extra_attributes(self, data):
         return {ATTR_RADON_LEVEL: radon_level}
 
 
+class BatterySensor(Sensor):
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        self.voltage = 0.0
+
+    def transform(self, value):
+        self.voltage = value
+        V_MAX=self.parameters[CONF_VOLTAGE_100] #3.2
+        V_MIN=self.parameters[CONF_VOLTAGE_0] #2.4
+        battery_level = max(0, min(100, round( (value-V_MIN)/(V_MAX-V_MIN)*100)))
+        return battery_level
+
+    def get_extra_attributes(self, data):
+        return {ATTR_VOLTAGE: self.voltage}
+
+
 DEVICE_SENSOR_SPECIFICS = { "date_time":Sensor('time', None, None, None),
+                            "battery":BatterySensor(PERCENT, None, DEVICE_CLASS_BATTERY, 'mdi:battery'),
                             "temperature":Sensor(TEMP_CELSIUS, None, DEVICE_CLASS_TEMPERATURE, None),
                             "humidity": Sensor(PERCENT, None, DEVICE_CLASS_HUMIDITY, None),
                             "rel_atm_pressure": PressureSensor(ATM_METRIC_UNITS, None, DEVICE_CLASS_PRESSURE, None),
@@ -171,6 +196,10 @@ def setup_platform(hass, config, add_entities, discovery_info=None):
     DEVICE_SENSOR_SPECIFICS["rel_atm_pressure"].set_parameters(
         {'elevation': elevation})
 
+    DEVICE_SENSOR_SPECIFICS["battery"].set_parameters(
+        {CONF_VOLTAGE_100: config.get(CONF_VOLTAGE_100),
+        CONF_VOLTAGE_0: config.get(CONF_VOLTAGE_0)})
+
     if not hass.config.units.is_metric:
         DEVICE_SENSOR_SPECIFICS["radon_1day_avg"].set_unit_scale(VOLUME_PICOCURIE, BQ_TO_PCI_MULTIPLIER)
         DEVICE_SENSOR_SPECIFICS["radon_longterm_avg"].set_unit_scale(VOLUME_PICOCURIE, BQ_TO_PCI_MULTIPLIER)