Teufel BOOMSTER User Manual page 20

Rechargeable Battery
The integrated Li-Ion rechargeable battery pack will be charged as soon as the
BOOMSTER is supplied with power via the 12 volt connection.
Before first use, charge the rechargeable battery for approx. 3 hours. In standby,
the charging of the rechargeable battery is indicated by five plus symbols (+) on
the display panel.
That or the last plus symbols flash and indicate the charge level of the
rechargeable battery. The flashing will stop once the rechargeable battery has
been fully charged. The typical playback time with full charged internal battery
is approx. 16 hours. To protect the rechargeable battery, the BOOMSTER has
deep discharge protection, which switches the device off once the threshold is
reached.
If the charge of the rechargeable battery diminishes or the batteries
are depleted, the message "BATTERY" will fast flash three times every
10 minutes on the display panel. In this case, connect the mains cable.
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