Approximately 23 hours of normal use.  EQ1 utilises state of the art NMH batteries which have a discharge rate of approximately 1% per month when not in use.
 You will be informed of expected battery available usage on start-up, shut down and whilst on charge.  It is also possible to check remaining time at any occasion during use.  A warning message will be heard of a low battery 4 hours prior to it going flat and a reminder every 2 minutes.