On Saturday, July 25, 2015 at 9:29:16 AM UTC-4, Robert Green wrote:
"yyy378" wrote in message

stuff snipped

The cell phone shows a battery with a green bar, a typical sign of
charging. However, after charging overnight, the battery still shows 0%
and when I unplug the phone, it quickly goes dead.

When I use the same charger on the same strip B, same spot, to charge
another phone, the percentage does go up, meaning it is actually charging.

Sounds like a dead battery in phone B. The indicators are often based on
voltage and batteries can show good voltage under very light loads (like a
metering circuit) but not have any real power to deliver when put under a
real load.

--
Bobby G.

If it was a bad battery then it would not charge when plugged into
strip A. Good grief.