Antigravity

Appreciate it on the XP-15!

We are unfortunately slowly working on the 992 thing... but we should also check on the Cayenne side too, but being blunt a bit busy on trying to design our next generation of battery with some new cool features. So my time is a bit taken, but again if anyone wants to try the 992 fix with us please drop me a line. The email is in the signature.

malba2366

It is unbelievable that they would build a system that locks out the battery permanently and not provide dealers the tool to unlock the battery or any kind of diagnostic information about the faults. If they are truly worried about someone charging a fully discharged LiIon battery they should program such that the battery will not start the vehicle should it fall below a 20% charge, and then the vehicle requires jumping. This is the kind of stuff that ends up with a class action lawsuit, because there is no legitimate reason to permanently lock out these batteries. If I am incorrect, please correct me @antigravity.

Antigravity

Well there is a legitimate reason to lock out a lithium battery that has been severly/extrememly overdischarged to the 2~4v range being they can claim safety issues due to the battery being over-discharged to this point and it may become unstable, but from what I am reading on Renn from the persons having these issues the batteries are locking out at the FIRST LEVEL of Protection which is usually just putting itself to sleep. . For example there is a Protection/Sleep Mode as the first level, which means the battery just puts itself into a sleep mode at a certain voltage. Then there is often a secondary protection mode at about 2v lower than the first protection for low-voltage and both these level usually can be woken up with a solid 12v source attached for a second. It appears from what people are saying that their battery is going into a permanant lock-out mode, or more likely they are at the first or second level of over-discharge protection, but the battery is just programmed incorrectly and is unable to come out of it protection mode. It should be waking up pretty easy with another battery attached to it.

In any event, this type of thing is not a Customer problem really because this protection is meant to prevent the overdischarge, and be realatively easy to wake out out of the protection mode. But if the Customer has let the Car sit 6-8 months and not driven or put a charger on the battery then it could have over-discharged to a point of permanant-lockout. But realistically I think this is just a matter of the 1st level or second level of protection not being able to wake up easily so it appear the batteries are just dead. I believe this because people are saying there are companies waking up the batteries and and when they wake them up the voltage is in a high state of charge of 10 or 11v...which is fine for a Lithium Battery. 2-4v is permanant lock out levels.

mathus7

Had the same warning light come on in my early production 992 and dealer replaced battery under warranty. Battery was functioning normally and fully charged but the warning light could not be turned off apparently due to some failure in battery management system that was built into battery.

kenv

Does anybody happen to know the date Porsche began building 9Y0's with the AGM battery? Are these battery problems plaguing every 2019-2021 Cayenne basic or has anyone been able to dodge the bullet? I'm wondering if it is just a matter of time before all the early cars have these problems.

George718

If enough of us complain Porsche will have no choice but to issue a recall......IMO it's inevitable

mathus7

My 992 was built during the first week of April 2019 - first week of builds for North America. My car is designated as "launch car". It was not delivered until October 2019 due to EPA /California holds. The yellow lighr indicating failure surfaced suddenly in May 2023. Another car I know of built one week later also experienced Li batterure failure.

dasams

Post 97 in the battery stickie thread in the Cayenne forum says that AGM batteries started in June 22.

Why am I researching these batteries? I woke up yesterday to a dead Li battery in my Cayenne GTS even though it was on a CTEK maintainer. Was able to restart it with my AntiGravity Micro-start and then I put it back on the CTEK. Checked this morning and the CTEK had all 6 green lit indicating a full battery. Pulled out the CTEK and the battery was dead. Currently at the dealer. Will know more tomorrow.

INS4NE_B9

I had the same thing happen.... I believe the CTEK charger overcharged the battery, which tripped the BMS. My CTEK charger was getting warmer and warmer during operation and I was a bit suspicious. I "woke up" the battery with a jump box, chunked the CTEK, and all is good.

FlyPenFly

Really at a crossroads on whether to keep my 2020 Cayenne with the LIFE battery. I had the recall done before failure but I don't want to be paying $1k/year in car battery if I keep the car long term.

George718

FWIW I had the recall done after the warning light first appeared.....9 months later the recall appeared again.....I got banged out for a new battery the 2nd time

BondJ

It’s normal for a Ctek to get warm during the charging phase to 80 per cent. From there, and throughout conditioning, it cools off

FlyPenFly

Is this theory correct in the sense that only cars that aren't driven very much have a potential for failure?

FlyPenFly

That sucks, what did it run you?

siberian

Anti-Gravity sells a kit (AGM and negative battery cable) to let you switch over from a LiFePO4 to AGM.

HOWEVER, IMHO, the problem resides not in the LiFePO4 battery but in the crappy BMS code. They can patch and do anything else they can conceive rather than admit ownership of the problem but until they revamp this idiocy called BMS the problem will be with us. My V8 Touareg is a 2008, it can sit for weeks with no problems. But then again it's a VDub, doesn't have an AGM or LiFePO4 and certainly doesn't have BMS.

siberian