911.1 Battery Issues for Infrequent Driver

[geedee]

Jonathanw, like you I have owned Porsches over a number of years and I even restored and maintained them myself at one time, for the most part using O.E. parts though not always, as there can ever come the time when the cost of keeping an old Porsche on the road can cost more in parts than it might be worth, more so when air cooling was left behind and market values altered...?
Today and for me personally the idea of paying out for an engine or gearbox replacement on my 991.1 is thought to be best avoided and the costs in OPC servicing to maintain the extended warranty is on balance of probability thought by me to be worthwhile for ME... Were it not for the availability of the Porsche warranty, I suspect I might have stuck to air cooled.....Each to their own.

My thinking relative to electrical safety and driveway charging was not so much related to charger protection but more relating to animals and humans, in that possible contact with normal household electrical supply voltages can be life threatening..
While modern homes may have have earth leakage protection circuit breakers on some circuits, it seems possible that older houses may have similar breaker protection for external circuits for lawn mowers and the like, it seems that there may be many homes without any such protection, thus a 240 volt flex strung out down the drive may present a degree of risk of a type worth assessing...? I think if you accidentally fry the postman the neighbours kids, or dog/cat/bunny wabbit, there could be potential legal issues..!

For those with older houses, it is possible to buy an earth leakage circuit breaker (ELCB) that plugs into a UK standard 13A socket, to which one can then plug a charger into.... However that is no guarantee of adequate protection, as the EARTH to the 13A socket has to be proven to to be sure the device operates as expected, if the supply lead TO the charger is to be considered protected..? I suspect most ELCB`s will have a test push button on them which SHOULD test the effectiveness of the earth connection TO the ELCB, by tripping the breaker when the button is pressed..?
As for ANY additional non O.E circuit connected to a Porsche with an electrical issue hopefully covered under warranty, even just a loose socket lying in the Frunk or elsewhere permanently wired in with nothing connected to it... Hmm..?
You have a strange electrical problem sir..? What is this connection for..? Ahh, a charger, well now it is just possible sir that your charger may have operated with some sort of temporary fault and generated a voltage or frequency which may have upset your Porsches sophisticated electrical system to some degree .....?

I guess at that stage your skills in negotiation might be under a bit of pressureto achieve a desirable outcome..?

 

[ravlondon]

Finally have a sorted solution to keep the battery in good health whilst car parked on the driveway. Thanks for all the advice. Here is my setup in-case it helps someone else. I used a qualified electrician to help set this up.

Dual gang outdoor socket (IP66 rated) on the outside of the house with switch on the inside of the house.
-->
A single gang extension (IP66 rated) running from there close to the car.
-->
This single gang socket is sitting inside a weatherproof box (IP54 rated) for extra protection and peace of mind.
-->
Plugged into the single gang socket is the CTEK MXS 5.0.
-->
The actual CTEK unit and wiring sits inside the car frunk (wire part comes out of frunk and goes into the weatherproof box).
--->
The CTEK is connected to the battery using comfort connector and extension lead.

Been setup for a few weeks with no issues.

 

[alisha.kihn]

I'm sorry to hear about the issues you're experiencing with your Porsche 991's battery. Here are some answers to your questions:
1. Choosing a non-OEM battery: Bosch S5 is indeed a reputable brand known for its quality. It's a popular choice for automotive batteries and should work well for your Porsche. Other reliable battery brands to consider include Optima, Exide, and Varta. It's recommended to select a battery that matches the specifications and requirements of your vehicle, including the correct size, voltage, and capacity.
2. Non-OEM battery and warranty: Installing a non-OEM battery may affect your warranty coverage. Most vehicle warranties specify that repairs or replacements should be done using original or approved parts. It's important to review the terms and conditions of your warranty or consult with a Porsche authorized dealer or service center to understand if using a non-OEM battery will impact your warranty coverage.
3. Maintaining battery charge: To keep the battery charged while your vehicle is parked for extended periods, you can try the following:
a. Use a battery maintainer or trickle charger: A trickle charger or battery maintainer can be connected to your vehicle's battery for long-term storage. It will provide a low, constant charge and prevent the battery from discharging. Make sure to use a charger designed for automotive batteries and follow the manufacturer's instructions.
b. Disconnect the battery: If you won't be using the vehicle for an extended period, you can disconnect the negative terminal of the battery to prevent any slow discharge caused by electrical systems. Keep in mind that disconnecting the battery may cause settings and stored data in your vehicle to reset.
c. Start the vehicle periodically: If possible, start the vehicle and let it run for a short period every few days or once a week. This helps keep the battery charged

 

[Lancerlot]

A couple of points arising:-
Using a non-OEM battery will invalidate any Extended Warranty in place. It's a third party insurance policy and your PC has no latitude in the matter. You can find details of Ctek smart chargers in the 991 Tricks and Tips section. (You need to be a member and logged in to access it.)
If you're changing batteries, your PC will need to reprogramme your vehicle's electronic system to recognise it and, if you disconnect the battery without an alternative power source, memory will be lost from some of the systems that will then need to be recalibrated.

Regards,

Clive

 

[geedee]

Seems this thread started on Dec 2022 and the OP reported back in Jan 2023 that his electrician provided a means of connecting a float charger to his car which seemed to assist matters relative to battery loosing charge when his Porsche was not in use for prolonged periods. He reported back after a matter of weeks.. which leaves me wondering if his fix is still working given the length of time many Porsches may be left unused or laid up..?
As I have posted before, I am no expert... However one who is on matters Porsche on another forum educated me to some degree relative to some of the component parts and programming which can create problems for seldom used Porsches of 991 vintage and beyond. Any replacement battery requires to be CODED IN as the battery management unit requires to be informed that a new battery has been fitted in order that it can alter the charging regime from that of the old battery which likely required a higher charge rate than the new one would require, given the old battery seems likely to have had a hard life due to lack of use and it`s storage capacity thus reduced. Possible end result, new battery becomes damaged as a result of overcharging...?
I have forgotten Porsches name for the battery management controller... was it the GATEWAY...?
As for the warranty... I bought a 3 year warranty at the time I purchased my 991, and in time also wished to replace my battery given it let me down once, and once was enough, Given the cost of the warranty there was no way I wished to compromise that, so bit the bullet and had Porsche fit and code in a replacement battery. Some time later, I had change-over valve issues and my OPC replaced three of them with no charge... Had I gone an alternative battery route... Hmm..?
This YT link is to a non-Porsche vid relative to coding in a new battery, and to some extent, aspects of battery replacement traceability. Hope it might expand understanding.
https://youtu.be/cxOK_DczRGg?si=s3QQK-lurqyBYrA1

 

[ravlondon]

OP here, can confirm solution I posted above continues to work. Has made huge difference when I don't get a chance to drive it weekly.

 

[geedee]

Many thanks for taking the time to report back. Also GREAT that your solution worked, given there are so many possibilities for voltage losses in Porsches that may not be in regular use, mine included.. Sigh..!