Laptop shutting off randomly

[Feyd Murphy]

So i have an asus x551ma laptop and recently its been shutting itself off every now and then, ive had it a year and its my most prized possession (I saved up for it) Ive taken it apart and checked the fan for dust and checked the heatsink, they where both okay, i did a system recovery and that seemed to help, but then it started again today, im starting to think that maybe its either the battery or it could be the heat sink after all, I have been using speedfan to check the temps and they are as follows

HDO: 36C
Temp1: 0C
Core0: 50C
Core1: 50C
That doesnt seem hot for a computer to me, but maybe it is?
Any help would be great, thank you

Update: Goes to sleep at 30% is that a battery problem?

 

[itmoba]

Which OS are you using? Typically, Microsoft Windows 7.x, 8.x, and 10 have built-in features regarding power consumption. Linux and OS X, too, have this "power saving" feature. It may certainly be that the current power settings is set to place the machine into hibernation if the battery is ≤ 30% charged and is not charging.

The temperatures are somewhat greater than ideal, so you ought to run a temperature diagnostic in the BIOS. Just monitor and write down the numbers and then tell me/us there readings you saw.

 

[Feyd Murphy]

Which OS are you using? Typically, Microsoft Windows 7.x, 8.x, and 10 have built-in features regarding power consumption. Linux and OS X, too, have this "power saving" feature. It may certainly be that the current power settings is set to place the machine into hibernation if the battery is ≤ 30% charged and is not charging.

The temperatures are somewhat greater than ideal, so you ought to run a temperature diagnostic in the BIOS. Just monitor and write down the numbers and then tell me/us there readings you saw.

The temps are the same as they where before, it cuts out as soon as taken off charge

 

[itmoba]

Sorry mate, but it would appear that it is, indeed, a dead battery. Unfortunately, each time the battery is recharged, some of its cells die. So, basically, if we were to assume that a fresh battery begins with of 100% of its cells functioning, then, when it gets to 50% the battery is being noticeably reported incorrectly. The reason this is the case is because when its being reported that there's 100% charge, it's really 100% charge for the 50% of the cells which still function.