yep, it says low voltage.
when it starts saying low voltage, you can't transmit anymore...but you can 
continue to receive for a while.
I recommend leaving the radio on until it shuts down before charging, at 
least for the first 3 times or so.
I don't know the percentage, but when it says low voltage, it's not quite 
dead obviously, so letting it run right down allows the battery to get a 
full charge for initial conditioning.
Should take about 3 to 4 hours to fully recharge.  The charger will 
automatically stop charging when the battery is full, so you can leave the 
battery in the charger indefinitely without fear of over charging or heat or 
anything.
if you get the 3600MA or 4000MA battery, all the same applies, and the 
battery will take about twice as long to charge compared to the stock 1800MA 
battery.

73
Colin, V A6BKX
----- Original Message ----- 
From: "Jed Barton" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Wednesday, October 03, 2012 8:04 AM
Subject: Baofeng battery indicator


> Hey guys,
>
> Anyone know if there is an audible indicator if your battery on the 
> baofeng
> is getting low?
>
> Thanks,
> Jed