Strange battery issues with fairly old Windows 7

[x800]

hi everyone,

today i started experiencing some very bizarre occurrences with my battery and the windows 7 battery icon
1. on bootup, instead of the usual battery icon, it was crossed out, saying "there is a problem with your battery, so your computer might shut down suddenly"
2. rebooting did not solve the problem
3. casting about the internet, i found that updating your bios could help. getting the latest files from asus, this did not solve the problem
4. i decided to drain the battery a little and then recharge it, to see if i could get anything
at this point the percentage remaining began to behave weirdly
the first thing i realised was that the battery was being drained at a ridiculous rate, on the order of 1% every half minute. This was on power saver and verified idle CPU and hard disk. I recognise that old batteries do begin to wear down and have reduced battery life, but given that only a month ago i was able to squeeze 6 hours out of a full battery I find less than an hour now totally ludicrous
Upon plugging in, the percentage stabilised at 79% plugged in, not charging
the battery charge light on the laptop was green, indicating full charge
i decided to repeat. The % once again fell very sharply. This time when i plugged in power the indicator turned red (charging), but the windows percentage jumped from 75% to 85% (or similar)
this continued to occur with subsequent tests, the % fluctuating wildly and the indicator light the only thing that i recognise as behaving normally
throughout this the error message of course did not go away

a system restore did not work
I did a energy report; the only error that seemed relevant was:
Battery:Last Full Charge (%)
The battery stored less than 40% of the Designed Capacity the last time the battery was fully charged.
Battery IDASUSTekK72J-44
Design Capacity48400
Last Full Charge15345
Last Full Charge (%)31
Platform Power Management Capabilities:ACPI _PSD Object Failed Validation
There is a problem with the definition of the ACPI _PSD object on this computer. Installing the latest system firmware (BIOS) may resolve this issue.
Group0Index0


Platform Power Management Capabilities:ACPI _PSD Object Failed Validation
There is a problem with the definition of the ACPI _PSD object on this computer. Installing the latest system firmware (BIOS) may resolve this issue.
Group0Index1


Platform Power Management Capabilities:ACPI _PSD Object Failed Validation
There is a problem with the definition of the ACPI _PSD object on this computer. Installing the latest system firmware (BIOS) may resolve this issue.
Group0Index2


Platform Power Management Capabilities:ACPI _PSD Object Failed Validation
There is a problem with the definition of the ACPI _PSD object on this computer. Installing the latest system firmware (BIOS) may resolve this issue.
Group0Index3



system specs:
Win 7 Home Premium 64 bit SP1
Asus notebook K72F series
intel i5
4GB RAM

This error has never occurred before
Any help would be greatly appreciated

 

[x800]

forgot to add: laptop is a little over a year old, i believe

 

[x800]

I've just tried unplugging and replugging power once more

it fell from 100% fully charged to 86% plugged in, not charging

 

[x800]

sorry for reposting again but the error has just decided to clear itself
i was simply working normally when it just went. no information, no nothing. helpful microsoft

apologies for the wild goose chase

 

[logicearth]

no information, no nothing. helpful microsoft

You mean, helpful battery/hardware. Windows only reports what the hardware tells it. Which is out of Microsoft's hands. Blame should go where it belongs.