diff --git a/zigate/__init__.py b/zigate/__init__.py
index ca69fb63..42e0a6f9 100644
--- a/zigate/__init__.py
+++ b/zigate/__init__.py
@@ -4,7 +4,7 @@
 from .const import *
 from pydispatch import dispatcher
 
-__version__ = '0.16.2'
+__version__ = '0.16.3'
 
 __all__ = ['ZiGate', 'ZiGateWiFi',
            'dispatcher']
diff --git a/zigate/core.py b/zigate/core.py
index 41ea5830..d6a256b7 100644
--- a/zigate/core.py
+++ b/zigate/core.py
@@ -1378,6 +1378,8 @@ def battery_percent(self):
             percent = 100
             if self.info.get('power_type') == 0:
                 power_source = self.get_property_value('power_source')
+                if power_source is None:
+                    power_source = 3
                 battery = self.get_property_value('battery')
                 if power_source == 3:  # battery
                     power_source = 3.2