Battery Guy

Oh boy....
Lots of information in this thread, and most of it is correct. But lots of it is no longer current. Today’s car batteries should never require anything to be added to them - they are either sealed (typically AGM) or supplied with enough electrolyte to last the life of the battery (maintenance free).
AGM will perform better but has less tolerance for overcharging, undercharging and abuse in general. Also they only last if they are not mounted in the engine compartment (like our 996’s) or my BMW (in the trunk). But - if your charging system is working properly, a standard battery will work well, and will cost less than AGM.
Battery tenders are great, especially with AGM batteries. Also the advice to drive the car is great too - car batteries are not designed to sit indefinitely on “float” and that will shorten the life somewhat.
Daryll

docmirror

I use "float" with a caveat that I didn't go into the storage charge, discharge, cycle, which is beyond the scope and rather detailed for a Porsche car forum. One can google the life cycle of batteries and how they operate. I say again, lead-acid batteries cannot be sealed. A battery on a proper charging system will have a absorption cycle, charge cycle, and a 'float' cycle. Now, we have entered the realm of battery esoterica, for which there is no escape. I"m getting off here, I've made my point, and the rest of y'all can disagree until full discharge is accomplished. I suppose to account for the even more pedantic, I should have used "smart" before "float". Or, "intelligent" maybe.

To repeat, drive the car, drive it for a while, don't make short trips repeatedly and expect the battery to survive very long.

adios

<edit to add, for those who are into minutia, here is the manual for aircraft batteries, which are rather sensitive to absolute right and wrong methods. An aircraft battery is designed to survive in strange environments, must be as light as possible, and operate without any potential for fire/explosion. It is 65 pages long. Report back if one finds an inaccuracy in anything I've written: https://www.manualslib.com/manual/12...25.html#manual >

dan_189

Had the same issue - bought a Ctek maintainer then replaced the Y cable - fixed

I have now just recently installed an Optima red top D34 with a YellowDog motorsports adaptor plate - quite happy with it.

Year ago I had an Optima blue top that lasted more then 7 years and I didn't even charge it on a maintainer!

dporto

^^ This is the problem with internet forums in general - lots of information, much of it right, much of it wrong, and much of it somewhere in between... Most people simply don't have the time to explain every detail regardless of their knowledge on any given subject, so things get boiled down/edited by the author and often misconstrued by the reader - then repeated, often exacerbating the misconstrued "facts"... It's a vicious cycle!!!

Mike Murphy

Once you get your car fixed, these handy jump start batteries can relieve anxiety and never leave you stranded again. Or if you are stranded, can power your cell phone for a long long time:

dporto

Gee Davey...where'd you go???

DBJoe996

@75 maybe I hope he's NOT six feet under

There better....not so dark

dporto

^^^ Uh... that's some dark humor Joe

TheYoung911

This went from informative, to funny, to dark faster than expected. Stay gold Rennlist, stay gold....

dporto

Davey's still missing though...

Railmaster.

Mine is a -94 993, it can sit five weeks without a problem but 993s from -95 and onwards with the remote controled alarm are notorious for draining batteries!

dporto

Davey still missing - maybe he was a TROLL !

808Bill

At 75, he may have forgotten all about his first and last post on RL.

dporto

75 is the new 60! (The Japanese say once you hit 60 you're already senile )...

DBJoe996

Dang! No wonder I keep forgetting stuff. At least now I have the excuse