+1 on that!!

I have an 01 S and use the Porsche branded CTEK charger via the cigarette lighter port. I would have bought the CTEK branded charger, but got a better deal on the slightly less capable Porsche branded one.

I upgraded my cigarette lighter port to smaller standard sized port that Porsche switched over to in 2003. Much better when plugging things like GPS, iPods, and chargers in (no more loose plugins). Pretty sure I bought the kit from Suncoast, but Pelican should have it as well. You shouldn't need it though for a 2005.

I just bought a battery and charger.....
 

...bought and installed this battery:

NSB-AGM94R (L4) Battery****| NorthStar Battery

and keep her charged through cigarette lighter with this charger:

CTEK Multi US 7002 - CTEK Battery ChargersCTEK Battery Chargers

Works like a charm.

Highly recommended.

Good luck.

:cheers:

Ctek schmetek
 

I bought the CTEK battery maintainer at my local stealership so it says "Porsche" on it. Maybe it cost twice as much, but I'm sure it works ever so much better than the identical one with CTEK on it. I've been using it through the cigarette lighter and the battery is still working fine after seven years.:)

The trick with CTek is to get the "Bundle" I linked above.Otherwise you'll get nickel & dime-d with the accessories.
I bought mine for $85 from "Jet"