LifePO4 battery already defective after 4 years

  • Hello everyone,

    With my Cayenne from 03/2020, not a hybrid, the message low battery always came up...the message was constantly there....so I bought a special charger, hooked it up and charged the battery. The message that the battery is fully charged came fairly quickly (on the charger).


    However, the low battery message is still there. Contacted Porsche Center and made an appointment. They came to the conclusion that the battery had to be replaced. The actual battery would not be defective, but a sensor installed in the battery's electronics package would probably be high-impedance and would fool the car's electrical system into believing that the battery was weak....this can cause all of the Cayenne's functions (e.g. assistance systems) to run unreliably.


    Repairs to the battery electronics are not carried out, only the complete battery is replaced...costs €2,200!!!


    Goodwill was rejected.....Not true...... especially since the approved warranty has just expired in 2023.....


    Have you had similar problems? Does anyone know an alternative, e.g. someone who repairs the battery electronics?


    Greetings Kokesch

    This post has been automatically translated.

  • Why such a battery in a Cayenne? For weight reasons? :kwink: Install a normal battery, which normally lasts much longer and costs only a fraction of the price.


    Greetings

    This post has been automatically translated.

    Nach 320'000 Spiegeleiern kann die Kantine nicht so schlecht gewesen sein!
    Harm Lagaay


    PS: Ich heisse nicht Greetz k:thinking:

  • Provided the information is correct and a small part, e.g. a diode on the BMS is defective, a repair / replacement is theoretically possible. In practice, it is more difficult because the manufacturers usually hermetically seal the housing and an open housing is likely to look unsightly.

    In addition, you first need to know who the manufacturer of the BMS is? Certainly not Porsche.


    From an economic point of view, this is 99.99% not worthwhile. Comparable, new LiFEPO batteries can be ordered from the largest manufacturers, i.e. those who also supply Tesla and Volkswagen (CATL, etc.) a brand-new and safe battery for a fraction of the price. Possibly even without the sensor that now tells the Cayenne that the battery is low?


    Or you can use a heavy lead-acid battery.


    If a lead-acid battery works, a CATL battery will of course also work.

    This post has been automatically translated.

  • There are proprietary connectors installed, which then go into the vehicle...quite difficult to convert...actually impossible...the only thing that would work is to remove the battery and repair the electronics, which sit on top.

    Then the battery has to be relearned after repair....this is no longer as trivial with the new premium cars as it was with my 2013 Boxter...unfortunately...

    This post has been automatically translated.

  • I don't know your battery. Nowadays it is common practice to install the BMS, which a LiFe battery requires, in the batteries because the BMS has to be wired to each individual cell. Unfortunately, this also means that you don't actually have access to the BMS. TÜV inspectors will certainly not approve of an open battery.


    If you can use an AGM lead-acid battery without any problems, it can't be that difficult. I wouldn't be too worried about 12 volt batteries anyway. Not to be compared with high-voltage batteries. That's a whole different ball game. I would never touch high-voltage.

    This post has been automatically translated.

  • TÜV inspectors certainly don't like an open battery.


    Since when does the TÜV inspector look at the battery? And under the seat?

    And the electronics are on top, you probably don't have to open the battery completely, see pictures in the ebay link


    Here is someone who repairs something like this, but you have to send it to the USA, but that's no problem either


    https://www.ebay.de/itm/185674757650


    or here


    https://www.ebay.de/itm/304916549697

    This post has been automatically translated.

  • Hello Jürgen,

    that's an insider tip...thank you very much. However, my battery is in the passenger footwell and not under the seat...but I measure approx. 13 volts there...the charge indicator in the cockpit also says 13.3 volts...anyway, Porsche says the only solution would be to replace it for €2,200........


    As my car has now been in the service center for 4 days, I gave the repair approval yesterday, I want to have my car back..... had also asked at independent Porsche workshops in Berlin, nobody wanted to do it.


    I'll have the defective battery sent to me, maybe I'll send the BMS to the USA for repair...


    Have a nice weekend!


    Greetings Kokesch

    This post has been automatically translated.

  • Hello Jürgen,

    that's an insider tip...thank you very much. However, my battery is in the passenger footwell and not under the seat...but I measure approx. 13 volts there....and the charge indicator in the cockpit also says 13.3 volts...anyway Porsche says the only solution would be to replace it for €2,200.....


    Good, but the TÜV inspector doesn't check the battery in the passenger compartment either......


    I don't know enough about the matter, i.e. I don't know what all the electronics in the battery do and what faults

    even if it appears to be charged or is being charged. Current consumption is different from current output.


    You only have to send the board, not the entire battery. Removal instructions should be available.

    However, reconditioned batteries are also offered, certainly cheaper than new ones from Porsche.


    Apparently this applies to all batteries of this type in the group (Porsche, Audi, Lambo).

    It may also only affect certain production years.

    This post has been automatically translated.

  • It's nice if you know where the inspector is looking. No matter, because an opened LiFE battery housing is not a problem at all, no matter where the inspector or perhaps the expert looks. This is because it is not a dangerous good. And repairing an expensive 2,100 LiFe battery yourself using the DIY method and using a US board instead of a Chinese one is a really good idea. Chapeau.


    Don't get me wrong, I don't care at all. But I would be interested to know which workshop offers to "saw open a 12 volt LiFE battery"? In case it ever starts to stew in the footwell.

    This post has been automatically translated.

  • It's nice if you know where the inspector is looking. No matter, because an opened LiFE battery housing is not a problem at all, no matter where the inspector or perhaps the expert looks. This is because it is not a dangerous good. And repairing an expensive 2,100 LiFe battery yourself using the DIY method and using a US board instead of a Chinese one is a really good idea. Chapeau.


    Don't get me wrong, I don't care at all. But I would be interested to know which workshop offers to "saw open a 12 volt LiFE battery"? In case it ever starts to stew in the footwell.


    Of course I know where the inspector looks, I've been there at least 30 times, that should be enough, right?

    The main points are: Lights, exhaust fumes (now the absolute focus because of the hysteria), rust on load-bearing parts, worn axle parts, brakes, nothing else.


    I don't want to repair anything myself and there is no question of a US board, only of repairing the existing board

    in the USA. What exactly is the problem? Or can only Germans do that, if at all? I'm curious to hear the reasoning


    For some things you don't need a workshop, you can do it yourself or just send the whole thing there and get it all back. I don't have any imagination for stewing, I take the lid off, put the lid on and sometimes it stews without any work......., so it's better to just ride an organic bike or carriage.


    BTW, I write what works and show possible solutions that are on the market in the world.

    I am NOT saying that YOU have to do all this.

    This post has been automatically translated.