Strange issue with my battery - Acer M3 - 581TG

[Zswizzy]

Ive had this laptop for a couple years(light use) and a couple days ago I thought the battery had died due to the laptop completly instantly shutting down, ~30 seconds after taking the power lead out. But I just noticed that when I plug it back in, Which is the only way it will let me turn it back on, It is still showing full battery power? Does this mean the battery isnt dead but something else is wrong?

I mostly just use it when travelling around on trains and such so the battery working is important, I have done my best to ensure that im not overcharging. I can't remove the battery but it shouldn't have died this quickly because i have been careful with it.

Running a week old windows 8 which i updated to 8.1 yesterday. (God I hate windows 8 so much.)

Thanks.

 

[Zswizzy]

So last night, I put it to sleep, unplugged it, then turned it on and it ran fine and slept and woke fine again. Then this morning, Turned on without the power again, ran for an hour or so and when i can back after 45 min away and tapped the mouse pad it instantly shutdown and wouldnt turn on again until I plugged in a power cord, despite having 25% battery.

Im really confused as to whats happening now because this isnt a clear cut battery is dead issue. Could it be a software issue?

 

[Zswizzy]

Bump, Someone must have some idea whats causing this?