I can't plug in a traditional batter maintainer because I live in a condo with a semi public underground parking structure. So, how often do I need to start it and how long do I need to run the car per month (or per week) to keep the battery good. I am just putting a new one in because of non-use. Thanks

 

you can use a quick disconnector to prolong the battery life. it will erase your radio code though.

i wonder if hooking up a portable battery jumper unit to the stock battery while car sits will prolong your battery life. It will draw some of the power from the portable battery I suppose.

 

How about a solar panel placed behind the windshield. These will keep the battery charged, at least on sunny days. They start at around $60.00. Now, of course, if the car is parked underground......it is not going to get much sun.

Yves

 

:-) (not saying this is a solution for you, but..) when I lived in Germany I used to take my battery in (the house) every night - a pain but it didn't freeze

 

How long do you currently leave you car inbetween drives?

 

I've had this same problem for years... I've found out that starting the car weekly is ineffective and in fact further drains the battery with every start. Idling the car even for 15 minutes probably won't charge the battery and my owner's manual says "avoid prolonged idling". I have resorted to swapping out car batteries every few weeks. I charge one at my apartment while the other one "drains" in my car, then I swap them out and repeat the process. It's a pain but I've haven't been able to come up with a better system. Good luck.

 

I am still amazed that a car this new and this high end has such a problem. My 03 dodge ram still has the stock battery and sits for two months at a time with out any trouble. Porsche has done a poor job on that part of these cars. I love my car but I would not take the battery out every day or week for that matter. If it came to that I would have to look for another toy for sure. Ok done ranting. I do think solor would be the best option if it is in the sun.

 

can be two weeks and sometimes even when I drive it, I don't go too far. Now, I live in a urban area, so it's parked a lot. I was just hoping to for example, start it and let it run 15 minutes once a week or something similar.

 

Actually seems like a pretty good idea! The battery is easy to get to.. and if I get a non-OEM battery, they are cheap.

 

I also reside in a condo and have been dealing with this problem as well. What I did over the past 3 yrs was to make an "effort" to drive the car 1-2x/wk for at least 1 hr while keeping revs above 2000 rpm. IIRC, by keeping the revs above 2000 rpm, the alternator start to charge the battery. This was what taught to me back in the days. This method has worked for me thus far and the battery is still going strong.

 

That's the best way. If the car is routinely not driven... why keep it? Stats show that sitting M96/M97 engines are more prone to serious RMS/IMF issues.

 

What about putting a deep cycle boat battery in the trunk and connect it to the car with suitable cables, fabricate one or use regular jumper cables. All sorts of DC power electrical parts are available at a marine supply. Take it into the house every couple of weeks and charge it up overnight.

 

Porsche does this on purpose so people will drive it more..

OP, ur only options are to
1- disconnect the battery when u r not driving it
2- use the two battery system like the post above
3- buy a house w/ garage
4- drive it more often.

i personally would go with #4..

BOL

 

I drive my cars at least once per week and usually twice . On the rare occasion I have let two weeks pass without a drive . I have never had to use a battery maintainer . I replaced my battery on my Turbo after 2.5 years pre emptive of it wearing out and my 997S still has the original battery which i plan to replace in December . I estimate that a 40 minute drive charges it .

 

One thing you might consider is when it comes time to replace, get an Optima. They are quite expensive ($150) but never need water and they "self discharge"-- lose their charge-- much less rapidly than normal flooded cell batteries. They recharge quicker and last much longer-- I have some that have lasted 6 years even in the AZ heat-- which is usually a battery killer. There are various threads on here on their advantages and how to install in your car. I put one in my '06 C2S with no difficulty, and actually have them in all my vehicles-- Tahoe, boat, etc. Except for the wife's new beetle convertible. It's not worthy!!!!