Battery Issues????

[sblythman]

Hey guys ive got an au xr8 that i supercharged the end of last year and it has been running fine since then but as of lately i have not been able to get out in it as often as i would like to (probably about once or twice a month).

The issue is the last two times i have taken it out for a drive i have turned the car off only to hop back in it and try and start it with absolutely nothing. Not even a flinch from the starter motor. i'll explain both times...

1st time - Got in the car started fine, drove about 6 minutes up to the shops and switched it off. Had the radio running for about 1-2 minutes not even loud and i went to turn it on and just nothing at all happened, no power to the starter at all but all the electrics where still working. Lucky i was on a hill and i was able to roll start it and took it home.

2nd time - Hopped in the car started fine even though the previous flat battery up at the shops?? drove it down to the golf course afterwards hopped back in it and again with just nothing from the starter motor and electrics were slow and so i had to get one of my mates to jump start it but it was reaaally flat, we had to run his car for 2-3 minutes before we could start mine. Drove it home and then i just went out to it then after a week of it sitting there and it started fine???!!!

So basically i only get a flat battery when i leave my house??? The battery has never been flat at my house (even after sitting for 1.5 months) but take it for a 25 minute drive and it wont start again?? Does anyone have any ideas??? is this just the basic symptoms of a dieing battery??