Porsche Cayenne LiFePO4 lithium battery

tycolash3 · #1

Has anyone had the experience of replacing this battery to the tune of $4200.00. Yes $4200 for a car battery. I've tried to research WHY and all information remains surprisingly nebulous regarding this topic for obvious reasons. Not being sure about anything, this is what /I think I know ??? or found. I have a 2019 Cayenne base model type 9YA/9YB. The Porsche LiFePO4 battery was supposed to last around 10 years but some are failing. In addition, the batteries have been damaged by defects in the Porsche BMS charging system as it overcharges the batteries and causes them to fail. Porsche ADVANCED TECHNICAL INFORMATION BULLETIN #222.8 shows a history of 8 revisions between 9/28/2022 thru 7/11/2022 with possibly more. I was told by my repair shop initially the battery was not covered under warranty. Then I was told it was covered under extended warranty in the "EMISSION CONTROL" category. But the damage was done and I was denied any recourse at the time. My understanding is this type of battery is in 2019 Cayennes to current as well as some 911's of similar vintage. I WOULD STRONGLY SUGGEST EVERYONE CHECK TO SEE IF THEY HAVE THIS FAILING BATTERY IN THEIR VEHICLE !!!!!!!!!!!! I understand it could be replaced by a regular battery but not sure. I was not told of that option at the time. I would suggest all affected owners contact their repair shop or dealer for more info. This issue would put many,many,many Cayenne and 911 owners capable of the same peril with Porsche"s full knowledge based on their technical bulletins. Could anyone tell me where I am wrong, incorrect, or "barking up the wrong tree". IF CORRECT ??????????? then every Cayenne and 911 owner with this battery should be made aware of this failing battery and it's $4200 approximate replacement cost.

#2

So far two Porsches with LiFePO4 and no issues. One was a '19 Cayenne Turbo (recently traded) that we had for 4-1/2 years from new and the other a '22 Turbo S.

I do keep LiFePO4 (and regular batteries) properly maintained so maybe that has helped. I use a CTEK for the LiFePO4 batteries - they like to be kept up but not overcharged as you mentioned and the CTEK does a great job of that.

I see a few mentions of overcharging due to issues with the Cayenne's battery charging software but they don't appear to be widespread based on what I've heard. Also, not sure why you lost the dealer's previous promise to replace the battery under warranty - why would they agree and then say no? Maybe ask to get PCNA involved to see if they will help. You can always appeal somewhere I think.

$4,200 seems a little high based on numbers floating around that are in the $2,500 range - admittedly still quite expensive. However, now I'm curious what the going rate is in our area.

If none of that works, have you explored replacing the LiFePO4 with an AGM battery? Maybe that can be done.

#3

From what I understand, the battery is under warranty unless it: 1. Damage from storing 2. Driving less than 6000mi/ year. 3. Damage by using wrong electrical device. However, car battery warranties are usually only 3 or 4 years.

As @blueline said that does seem a little high. Perhaps they REALLY charged up the labor costs, but from what I have seen, $2500USD is the typical cost for a replacement.

There is not a whole lot you can really do in these cases except source out a cheaper Li battery option, and put it in your self.

#4

Quick google suggests Porsche has a bit of an issue with this one. Sorry about that. That said, if they won't cover it, I'd be inclined to get the part number and see what the cost is at the parts counter and/or ask the dealer to break down that $4,200 quote into parts and labor to see if they are just over-pricing it, or if they want to do more than a simple battery swap.

Stevewcpa · #5

blueline wrote: ↑Mon Jul 22, 2024 7:48 am So far two Porsches with LiFePO4 and no issues. One was a '19 Cayenne Turbo (recently traded) that we had for 4-1/2 years from new and the other a '22 Turbo S.

I do keep LiFePO4 (and regular batteries) properly maintained so maybe that has helped. I use a CTEK for the LiFePO4 batteries - they like to be kept up but not overcharged as you mentioned and the CTEK does a great job of that.

I see a few mentions of overcharging due to issues with the Cayenne's battery charging software but they don't appear to be widespread based on what I've heard. Also, not sure why you lost the dealer's previous promise to replace the battery under warranty - why would they agree and then say no? Maybe ask to get PCNA involved to see if they will help. You can always appeal somewhere I think.

$4,200 seems a little high based on numbers floating around that are in the $2,500 range - admittedly still quite expensive. However, now I'm curious what the going rate is in our area.

If none of that works, have you explored replacing the LiFePO4 with an AGM battery? Maybe that can be done.

I feel very lucky with my 2019 Cayenne Turbo. Bought it with 21k on the odometer, at 31k the water pump failed. This the dealer covered under transferable CPO warranty. While they had the car the battery died. They replaced it, also under warranty. They have earned my repeat business.

#6

@Stevewcpa

Welcome to Carpokes!