Originally Posted by sebastianlow
Just now I was watching a few videos on my XZ, the battery went flat and I charged it for awhile. I tried turning on the phone after that and I could not power it on at all. I tried using the volume up/down + power hard reset thing and it would not reset. What can I do to save this phone?
Leave it be for 24-48 hours.
Plug it in the charger, if nothing happens, unplug it and try again a few hours later. If after 3 tries nothing happens, just plug it in and leave it be for a day or 2 and see what happens.
Li-Ion batteries are known for their safety circuit that is built-in, which prevents an absolute discharge of the battery, which would damage the battery and make fireworks as soon as you would recharge it. They prevent it by stopping the current flow, and usually it's really no big deal, unless you have a sealed phone like we do...
In the worst case, a phone service would need to open up the phone, and boost the battery with a diagnostic tool such as those from Cadex.
It will cost you a service fee + back cover gasket (gasket costs approx 5 - 20 dollars, depends on how hard the shop wants to rip you off).
The reason for you to wait, is because the battery can regain some charge, as in collect the last bits. Remember how dead batteries would still give quite strong light in a flashlight that was completely empty the day before? Just that little amount would be enough to unlock the battery again and you'll be able to charge it.
Be patient, otherwise try a service and ask for a battery boost, in case they find out it's a sleeping battery.