The tablet was working fine then all of a sudden the battery started losing power rapidly. If I take it off the charger it says 100 percent full, but in about 5 minutes it will shut down and the battery will be depleted.
You can try adjusting the settings on the tablet to conserve battery. If they do not work you will need to return the unit back to dell for servicing.
Charging and managing your battery on the Dell Venue 8 (7840) tablets