How long did your battery last
#16
Race Car
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The original battery on my 2012.5 C2S lasted 7 years. It failed suddenly about 3 months after a routine dealer service when it was tested and found to be just fine. I had requested it be tested due to age and was told the battery had a "slow failure" mode indicated by slow cranking. Not so- when it failed, it sounded catastrophic- like the transmission was eating the engine.
I called to scream at the service manager, and he suggested I hook up the battery tender for a half hour, try again, and if it then started to bring the car in for a new battery. That worked. So I would consider time after 7 years as good luck. PS - the dealer matched the best replacement price I found elsewhere.
I called to scream at the service manager, and he suggested I hook up the battery tender for a half hour, try again, and if it then started to bring the car in for a new battery. That worked. So I would consider time after 7 years as good luck. PS - the dealer matched the best replacement price I found elsewhere.
#17
Burning Brakes
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2012.5 C2S with 25k miles here, original battery.
#19
Rennlist Member
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Other than those "choosing" to replace a battery quite early and long before it fails, it is nice to see the factory original and installed batteries last as long as they do and failing in the near 10 year period. I wonder if the Banner batteries are available from dealers here or if they are using a Porsche NA local supplier? I won't know till I need to replace it.
I also noticed from reading some replies on RL that my battery voltage is in the mid to high 14s in Sport Plus mode and when disabling that mode it reverts back down to the high 13s (variances at each mode based on temperature). In which case, it being an AGM battery, I'll leave it in Sport Plus mode. Maybe one day out of curiousity I'll hook up my MadgeTech data acquisition to the battery to get a complete picture based on modes and temperature.
I also noticed from reading some replies on RL that my battery voltage is in the mid to high 14s in Sport Plus mode and when disabling that mode it reverts back down to the high 13s (variances at each mode based on temperature). In which case, it being an AGM battery, I'll leave it in Sport Plus mode. Maybe one day out of curiousity I'll hook up my MadgeTech data acquisition to the battery to get a complete picture based on modes and temperature.
#21
#22
Rennlist Member
#23
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Battery life is directly related to use and cycles. I have a 2013 Honda Foreman with original battery (10 years old). It stays on a tender. I have boat batteries 12 years old, again not many cycles per year vs car. my Dailey driver the battery will last 2.5 years in miserable houston. Original battery in 2017 991.2 and 100% confidendent in its ability with only 20K miles. If I do change I will go to Walmart and buy an AMG group H8 for $189 Sooooooooo in the end you feel good about having a new battery replace at 5 years. H8 is size of battery in your C2.
#24
Rennlist Member
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I'd say normally yes, BUT my 14 year old Honda CR-V with the factory fitted Panasonic battery had 152,000 miles on it. Sold it to my Porsche friend then and after a few months, he replaced it when it when it ended up being the original starter (which could have been rebuilt). And by the way, that battery had to start my car down to -23F in the winter.
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HardRider (09-02-2023)
#25
Intermediate
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I purchased my 2012 991 C2 in May this year with about 25,000 miles. I’m the second owner, and I’m unsure of battery age. I’m using a battery charger/ maintainer. I’ve noticed that if I wait a couple of days after driving to put on the maintainer, the battery is at about 60% charge. Do you think I should replace?
Last edited by First991C2; 09-05-2023 at 02:21 AM.
#26
Rennlist Member
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Original battery on my 2017 which I believe based on the date stamp is now 7 years old. I semi-daily use my vehicle putting about 4K miles/year. Occasionally put on a CTEK trickle charger whenever I know the car is going to sit longer than a week although I know that’s not necessary. I recently thought that it was going to be time to change my battery as I felt it was getting slow to crank (after installing a P3 Gauge) but that seems to have turned out to be either nothing or completely in my head and is no longer a concern. I still however remain aware that 7 years is a good long life for an average car battery and am ready for that moment when the car starts acting like gremlins and need to replace. Would love to get an OEM replacement since those seem to have such a great track record but can’t justify the dealer price.
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shammerman (09-05-2023)
#28
Rennlist Member
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I purchased my 2012 991 C2 in May this year with about 25,000 miles. I’m the second owner, and I’m unsure of battery age. I’m using a battery charger/ maintainer. I’ve noticed that if I wait a couple of days after driving to put on the maintainer, the battery is at about 60% charge. Do you think I should replace?
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First991C2 (09-13-2023)
#29
Rennlist Member
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And in the end you can buy an AGM for $180 to $250 and that is a long shot from spending $1200 for an overpriced Lithium battery.
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shammerman (09-05-2023)