Windows 7 randomly shutting itself down on battery mode?

I have an ASUS G50vt-X5 laptop running Windows 7 SP1 which without warning or notification, shuts off randomly. It shuts off suddenly, like someone pulled the battery out without the notebook being plugged in.

I just purchased a new laptop battery which gave me 2hrs 30min of run time for 2 weeks until today. BatteryCare said it had a 4.5% wear level out of the box and now it says 2.5%.

The laptop always shuts off at the 70% battery level. I have to turn it on again and the laptop runs on the battery for another 60 minutes before dying. Total run time is now 1hr 30min or 60 minutes less than it should be.

It's only been through 20 discharge cycles since its last calibration. I've double checked all the power plans' advanced settings - low and critical battery notifications/actions kick in at the 15% range.

CPU temp hovers between 107 F and 120 F while watching HD videos on Netflix. I haven't changed any BIOS settings recently etc.

Is this a software problem or a problem with the battery?

Update: Laptop randomly shut off at the 38% battery level.

 

Bad battery.

 

ill second its a knackered battery.

after my original battery only lasted a year i got it replaced and now this one is 2 years 4 months old and still has 98% charge.

leaving a battery connected while its using mains power for long periods of time shortens its life.
its recommended by battery care that it should be left with about 40% charge when its not connected to the computer for long periods of time.

 

^ this always comes up.

I know lots of laptop batteries that have lasted years whilst on power. It isnt the manufacturers Battery software conflicting with windows battery software? Like S0ny Laptops