Help Samsung Galaxy S2 turned itself off while on charger overnight, was hot in the morning

[gsaracen]

Hi,

Recently my phone's alarm failed as the phone turned itself off overnight, even though it was connected to the charger. Te phone felt hot in the morning, in spite of being off and I had to jam the power button for a long time multiple times before it turned on.

When the phone turned on, the battery was at 100%. I typically leave the phone on the charger overnight and I have not had this problem before. The alarm was supposed to go off at 7:30, I woke up at 10:30 and found the phone to be off and somewhat hot. I typically do not miss alarms and wake up to them just fine. Thank god it was the weekend, otherwise I could have been fired. Needless to say this can never happen again.

I am on vodafone in the UK, model GT-19100, Android ver 4.1.2

I don't know how to check for the version of my firmware.

Could someone help me figure out what happened and how to prevent it from happening again?

 

[Hadron]

It's hard to say, but the most worrying possibility would be a problem with the charger circuit or the battery (possibly leading to a shutdown due to overheating). Certainly I'd take the battery out and have a look at it: if it's started to swell even slightly you should buy a replacement and not use the current one, since a defective battery is a fire hazard.

Otherwise, I'd certainly try charging the phone a bit earlier tonight, so you can see whether anything odd happens.