Battery query

[tehidyman]

My tablet is nearly two years old.  Recently it behaves as follows.
It starts off 100% fully charged – daily use of about ten to fifteen minutes visiting three websites results in the battery dropping by about 9 percent a day.  After 5-6 days it falls to 50 percent left but next day it has all gone. This has happened three times.
Searching has not identified the cause, cure or future behaviour.  Can any idnetter advise?

[Technical Ben]

Battery is old and probably one of the cells is failing. So it holds charge well for 50% then dies... where are nice healthy batteries hold voltage and slowly loose it, an old battery will suddenly loose it.

Though it may be the battery software needs retraining. Depends on the device, but a factory reset may be needed. Is it an Apple or Android tablet? Which brand if Android (Samsung, Asus, etc)?

[tehidyman]

It is an Android Nexus 7 2013 7"tablet.