Porsche 718 Forum banner
1 - 20 of 41 Posts

·
Registered
Joined
·
215 Posts
Discussion Starter · #1 ·
I have a new 2022 boxster gts two months ago delivered so battery is brand new. Im leaving for vacation on a Tuesday and can have my son start the car (not drive it cuz he’s not insured) on Friday thru Sunday morning and then again the next weekend on Friday thru Sunday and then im back on Tuesday. So the car will not be driven for 13 days straight but not started up for no more than 4 days straight.
Do i need to connect the car with a battery charger i have the porsche original one. I prefer not to because nobody will be home and am worried for malfunctioning and fire hazard.
If i come back and the car doesn’t start if I connect the battery charger will that fix it?
 

·
Registered
2021 718 Cayman GTS 4.0
Joined
·
925 Posts
You can go weeks to months without starting the car and it will be fine. I would never do what you are proposing - starting it daily without driving it. Without letting the car fully warm up, you will not burn off any condensation in the oil. These cars like to be started up and driven right away.

The chances of a fire from a battery charger are pretty remote. Probably not much higher than a fire from any other cause.
 

·
Registered
2021 Boxster
Joined
·
2,402 Posts
Have gone over two months without starting. No problem. Car is garaged, A/C at 78, top down.
 
  • Like
Reactions: RedCayman07

·
Registered
2018 Cayman S
Joined
·
204 Posts
I have a new 2022 boxster gts two months ago delivered so battery is brand new. Im leaving for vacation on a Tuesday and can have my son start the car (not drive it cuz he’s not insured) on Friday thru Sunday morning and then again the next weekend on Friday thru Sunday and then im back on Tuesday. So the car will not be driven for 13 days straight but not started up for no more than 4 days straight.
Do i need to connect the car with a battery charger i have the porsche original one. I prefer not to because nobody will be home and am worried for malfunctioning and fire hazard.
If i come back and the car doesn’t start if I connect the battery charger will that fix it?
Cars today, including Porsche, are not fragile. Mine has gone for more than 2 months without use, a charger, or problems when starting it again. If you are REALLY worried about it, put a charger on it when you get back. More than two or three months I would probably put a trickle charger on it.
 

·
Registered
2018, GTS, PDK
Joined
·
787 Posts
Twice this year already, I have left mine on the drive, outside for 2+ weeks each time.
No issues whatsoever AND I believe its on its original battery - 2018, so believe you will be ok here with new.
I do have a trickle charger just in case and interesting comparison is my last car (Merc Convertible) purchased brand new was always having issues with the battery leaving it for similar periods - do believe though some or even most Mercs have 2 batteries anyway and it was the smaller giving the issues hence getting a good trickle charger to resolve. Touch wood - never had to do any of this in my 718.
 

·
Registered
Joined
·
203 Posts
Unproven rumor has it that regular use of an AGM smart charger might extend the life of the OE battery. Maybe yes, maybe no, but I'm on year 6 of the OE battery and voltages are still good; Varta.
 

·
Registered
Joined
·
615 Posts

·
Registered
Joined
·
2,195 Posts
From the FWIW department, the issue with not keeping a battery charged either by driving or with a charger/maintainer is that non-lithium batteries do not tolerate becoming too discharged. In an RV or travel trailer you rely on a deep-cycle battery for all your electricity needs when camping not connected to a power grid. In those circles they say that you shouldn't let it drop to below a nominal 50%. Admittedly that figure probably isn't a hard number and may just be urban legend. Regardless of its accuracy, a battery that low may still have plenty of energy left to start the car but it shortens the battery's life.

Our cars cars have a lot of background uses for electricity when not running. I suppose that might depend on what services the car does or doesn't have. I know that I have occasionally gone for two weeks without driving, and when I put a battery charger on it the display said it has around 50% or even a bit less.

Like mileage, your battery usage may vary.
 
  • Like
Reactions: Barryng

·
Registered
Joined
·
215 Posts
Discussion Starter · #17 ·
From the FWIW department, the issue with not keeping a battery charged either by driving or with a charger/maintainer is that non-lithium batteries do not tolerate becoming too discharged. In an RV or travel trailer you rely on a deep-cycle battery for all your electricity needs when camping not connected to a power grid. In those circles they say that you shouldn't let it drop to below a nominal 50%. Admittedly that figure probably isn't a hard number and may just be urban legend. Regardless of its accuracy, a battery that low may still have plenty of energy left to start the car but it shortens the battery's life.

Our cars cars have a lot of background uses for electricity when not running. I suppose that might depend on what services the car does or doesn't have. I know that I have occasionally gone for two weeks without driving, and when I put a battery charger on it the display said it has around 50% or even a bit less.

Like mileage, your battery usage may vary.
In other words not driving for two weeks and not maintaining the battery with a charger during that period shortens the battery life ? And using a charger during those two weeks is better for the battery’s life soan?
 

·
Premium Member
2017 boxter 718
Joined
·
366 Posts
i wrote here several months back. "i've never seen a car line (porsche) or model in particular (boxster) cause so much
angst among the owners".
i thought ferrari owners suffered mightily from this affliction. most are subdued by comparison.

years ago, my mother brought me home "worry beads" from nepal. they were to be used like a rosary. i was in university
at the time and was suffering from the usual college student malaise.

in giving me the beads, her reason for them was their intended purpose: "life never stays stagnate.so get over it"!
 

·
Registered
Joined
·
804 Posts
We do not have conventional flooded lead acid car batteries that are not at all tolerant of being even slightly discharged. They are specifically designed to provide a lot of energy for a very short period of time (seconds) to start the engine and then be immediately recharged in a very short period of time. The plates used in conventional flooded lead acid batteries soften (not good in a moving platform) and warp (and maybe short to adjacent plates) as they become discharged. Also, the sulfate deposits harden effectively removing surface area. The capacity associated with that surface area is now no longer available. The construction also makes them vulnerable to mechanical shock which, of course, is part of their existence in a moving car.

However, we do not have conventional flooded lead acid batteries. We have AGM batteries. AGM batteries are still lead acid chemistry but they are built very differently. Every car I have had for the past 12 years has had AGM batteries. These batteries are not flooded batteries, structurally very robust, tolerate deep discharge much better than flooded lead acid batteries, have a much lower self discharge rate than flooded lead acid batteries, and are maintenance free. I have heard that 50% discharge is max recommended but I am not sure of that. In any case the threads on this board and a BMW X3 board I used to visit frequently pop up with concerns for trickle chargers etc. In my opinion, there appears to be a lot of undeserved paranoia about this subject. The advice in the posts above is mostly all very good advice. Just leave the thing alone unless the car will not be used for a very long stretch (many months).

Also, I frequently see a concern about driving only a few miles to work and not fully charging the battery. Dealers use this as an excuse to not fix an electrical problem. This is also an problem founded on only paranoia. If you look at the amount of energy needed to start the car and the rate the big ass alternators we now have pump that energy back in, the battery fully recharges from starting in a very short period of time. I also noticed, starting with my 2011 X3, the electrical systems maintain proper voltage even at idle. For a few years I had a client in unreasonably cold/snowy/miserable Upstate New York. In the morning in near or sub-zero temps, I would start my X3, turn on headlights, window defroster full fan, seat heaters, rear window heater, and steering wheel heater and then remove the ton of disgusting snow on the car. I noticed, without exception, with this large electrical load, the electrical system maintained 14.6 volts or so at idle meaning the alternatior was not only carrying 100% of the load it was also providing 100% of the battery charging needs. My trip to the plant was only 7 miles and I never had a problem keeping the battery charged. I am certain the electrical system in our Boxsters is equally robust. As a side note, it is a misconception that a battery cannot be charged when the car is idling. Simply controlling alternator output voltage via the electronic voltage regulator and the computer maintaining idle RPM is all that is needed.

BTW, while on this subject, there is only a a few tenths of a volt difference in charging voltage for the two types of conventional lead acid batteries, regular ones and maintenance free. Installing a maintenance free battery in a car designed for a non-maintenance free lead acid will result in it failing in about a year (my experience) solely because the required charging voltage for a maintenance free battery is a few tenths of a volt higher than the car with a non-maintenance free battery. That few tenth of a volt undercharged takes a toll over time in lost capacity due to hardened sulfate deposits.
 
1 - 20 of 41 Posts
Top