Canon BG-R10 Instructions Manual page 16

Caution
To protect the battery pack and keep it in optimal condition, do not charge it
continuously for more than 24 hours.
If the charging lamp fails to light up or a problem occurs during charging (shown by
the charge lamp blinking), unplug the power cord, reinsert the battery, and wait a
few minutes before plugging it in again. If the problem persists, take the camera to
the nearest Canon Service Center.
The charging time required and the amount charged vary depending on ambient
temperature and remaining capacity.
For safety, charging in low temperatures takes longer.
The remaining battery level may decline when power is supplied to the camera. To
avoid running out of battery power, use a fully charged battery when shooting at
regular intervals.
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