Battery Protection Limit

[Bakerjoe]

The car had charged from 70% starting at 1am, reached 80% at around 3:30 and the car stopped charging. But 9 times after that until 6am (the end of my off-peak electricity rate), there was a short spike of current. I assume it was trying to continue charging, but the car was refusing it as it was at its configured maximum of 80%. If it was waking up each time it was doing that, it was probably triggering the dashcam too, which is plugged into a USB socket, and that would of course drain the 12V battery.

That’s not something to do with the car conserving charge, is it? As in, when it’s plugged in and finished charging, it should draw a little from the charger to maintain the charge level. While that shouldn’t change over such a short period, maybe the temperature affects the estimated % or something?

[Skku]

I did have a 80x before and now a 85x. On the older car (80x) never had this problem. Not even when it was -30c.

On the 85x I got the same problem as everyone else when the temperature was below 4c.

According to the service technisian the problem is caused by the 85x having a crappy kind of 12v battery. They changed my battery to a AGM 12v battery....and everything has been working seens before Xmas without problems!

How ever - I hope that Enyaq in the future will automatically charge the 12v battery from the high voltage battery!

[CrowSysE243]

How ever - I hope that Enyaq in the future will automatically charge the 12v battery from the high voltage battery!

At least since last November mine does, however it does not start charging until the controller reports a 12V battery 50% state of charge and the remote functions are inhibited at a higher level, which appears to be temperature dependent. The remote functions are re-enabled as soon as charging from the HV battery starts and charging continues untole 90% state of charge.

The car has not been used for 3 days and the remote functions became inhibited a few hours ago with the state of charge between 66% and 70%. Last week it was in an airport car park for nearly 7 days and remote functions became inhibited for 18 hours on day 7, but recovered before I returned to the car, at which time the state of charge was 80% and the 12V Battery total charge had increased since the car was left.

[Skku]

How ever - I hope that Enyaq in the future will automatically charge the 12v battery from the high voltage battery!

At least since last November mine does, however it does not start charging until the controller reports a 12V battery 50% state of charge and the remote functions are inhibited at a higher level, which appears to be temperature dependent. The remote functions are re-enabled as soon as charging from the HV battery starts and charging continues untole 90% state of charge.

The car has not been used for 3 days and the remote functions became inhibited a few hours ago with the state of charge between 66% and 70%. Last week it was in an airport car park for nearly 7 days and remote functions became inhibited for 18 hours on day 7, but recovered before I returned to the car, at which time the state of charge was 80% and the 12V Battery total charge had increased since the car was left.

I don't know were you live. But the SOC change of the 12v batty....could it be because of changes in the weather? If the car is charging the high voltage battery the 12v battery is charged at the same time with 13.3v. If the car automatically would charge the battery when off-grid I guess it would charge the battery also at 13.3v (or 15v as when your in drive). Can you see if the car does that?

[MK09]

Nice of ŠKODA to include permanent notification in the latest 8.0.0 version of the app that the battery protection limit has been exceeded. This within seconds of arriving home after a 50 mile trip:

[oneman]

I have an 85x 2025 from October, 2024.
I am using android app CarScanner with my OBD2. I have noticed the 12v SoC increasing while driving, but there is also a 12v "Battery aging by power/capacity", not changing while driving. When I started reading these data started at 82% and has now degraded to 79%. When passing 80% battery limits in app appeared (mayby it was same time MySkoda v 8.0.0 was released).
Does anyone know when "Battery aging by power/capacity" becomes critical low and when 12v battery needs to be replaced? Does Skoda technichans have a threshold value for replacement. I am quiet nervous to be stranded somewhere.

[CrowSysE243]

How ever - I hope that Enyaq in the future will automatically charge the 12v battery from the high voltage battery!

At least since last November mine does, however it does not start charging until the controller reports a 12V battery 50% state of charge and the remote functions are inhibited at a higher level, which appears to be temperature dependent. The remote functions are re-enabled as soon as charging from the HV battery starts and charging continues untole 90% state of charge.

The car has not been used for 3 days and the remote functions became inhibited a few hours ago with the state of charge between 66% and 70%. Last week it was in an airport car park for nearly 7 days and remote functions became inhibited for 18 hours on day 7, but recovered before I returned to the car, at which time the state of charge was 80% and the 12V Battery total charge had increased since the car was left.

I don't know were you live. But the SOC change of the 12v batty....could it be because of changes in the weather? If the car is charging the high voltage battery the 12v battery is charged at the same time with 13.3v. If the car automatically would charge the battery when off-grid I guess it would charge the battery also at 13.3v (or 15v as when your in drive). Can you see if the car does that?

I live in the south of England so the climate is relatively mild.
I think that the reported SoC for the 12V battery does change with temperature, however most of the change that I have seen is not likely to be the result of that. There is a consistent downward trend until 50% is reached independent of the temperature trend.
When my car is charging the HV the 12V battery is also charged. The DC to DC convertor (DDC) output volatage reaches about 15V but it seems that the DDC voltage drops to around 13 to 13.5V once the 12V SoC reaches 90% from the limited data that I have.
When the car is not plugged in and is not charging it appears that the DDC will be switched on when the 12V SoC drops to 50% and stay on until 90% SoC is achieved.
When the car is "Switched on" the DDC is switched on at about 15V to run the car systems and also charges the 12V battery. The 12V SoC can reach 100% in this case if driven for long enough.

I want to get some more detailed long term data and the methods that I had available (OBD2 dongle or BM2 battery monitor) do not provide the facilities I want so I have put together a battery powered voltage logger that I can connect to the 12V socket and collect data over a week. Because it is plugged into the socket in the boot, the voltage recorded will not conform to the battery terminal voltage and will be affected by current drawn by other circuits, so will see transients not apparent at the battery. I completed assembly yesterday but have not yet calibrated it, however a quick check suggests that it is within 200mV at 12V input. After the Skoda server problems yesterday, which Home Assistant logs suggest lasted from about 08:25 to 11:45 I found that the app (version 8.0.0) reported "No connection" without the app reporting that remote services had been disabled. I speculate that the 12V SoC had dropped sufficiently that remote services were suspended at some point while the server was offline so the car could not report the condition. As the app still reported "no connection" when the logger assembly was completed I connected it to the car and left the logger running with a 10 second sample interval. I was unable to use keyless locking at this time, as expected. I have not analysed the data that I downloaded this evening but I find some aspects interesting.

The car had been parked since 14:30 on Thursday, with Car Scanner reporting 98% 12V SoC. The car was not connected to any charger.
When the logger was connected at 22:53 on Saturday, Car Scanner reported 52% SoC.
The voltage log shows that the DDC switched on at 22:59 on Saturday and remained switched on until 23:43. This is consistent with behaviour previously observed.
There is an unexpected voltage excursion between about 00:05 and about 00:50 on Sunday morning. Further investigation is needed to see if this recurs and what may be the cause.

When I accessed the app at 07:06 it showed that the last report from the vehicle had been 54 minutes earlier. As I did not use the app until the morning I cannot confirm when remote services would have become available but it is likely that this would have been at 22:59, based on previous observations. There is a voltage spike, consistent with the DDC switching on, at the time that the car is "Activating" (The new name for waking up?), followed by a dip. There is an earlier dip which coincides with the time that the app reported the previous update from the car. The dips could be due to current being drawn for communications and causing voltage drops in the wiring. There are also earlier dips.

The recorded voltage is showing a downward trend, with some dips, which continues until the car was driven at about. During this time the external temperature was reducing from 2C to 0.1C at 03:50 following by a gradual increase to 4.9C at 13:15.
There is a downward trend between each period of driving the car. When the car was unlocked ahead of most of the driving periods the voltage dropped.
During the first driving period there are some unexpected high voltage spikes recorded. It is possible that the logger input cables are coupling with something. They do not appear to be in data from Car Scanner

.
I think I will collect some data including the next smart charge before making any changes to the recording set up and carrying out any planned experiments.

[Aragorn]

What are you using for logging? I'd like something similar to help diagnose an issue with my old land rover.

I could always try attaching it to my older Enyaq for comparison?

Those wild excursions are quite odd, pushing voltages up to 16v+ isnt going to be doing the battery any good?

[grebble]

Just an update on my experiences with these issues. Since keeping the key away from the car, turning off the wake-up in the app, and using the Ohme app to regulate charging instead of having the car stopping it at 80%, I've had no further appearances of the battery protection message. I've just left it for a week at Gatwick Airport and had no issues at all when I returned. However, it is a lot milder now than it was when I left.

My 85 Coupe is a later build - December 2024 - which I believe is after those with the batch of bad 12v batteries. So I think my issue was simply with the key, app and charger waking the car up when it didn't need to be woken, and triggering the dashcam. Not the same as what others have been having here.

[CrowSysE243]

What are you using for logging? I'd like something similar to help diagnose an issue with my old land rover.

I could always try attaching it to my older Enyaq for comparison?

I have assembled a logger using a Lascar Electronics EL-OEM-3 Voltage Data Logger. This runs from 2.75 to 3.6V so can be powered from 2 AA batteries, and has a full scale input range of 0 to 2.4V DC but the readings can be scaled in the EasyLog software used to configure it and download the measurements if a resistive otential divider is used at the input. It wil record over 64k samples with sample rates from 1 second to 12 hours. I have housed the logger, a ~10:1 divider (910kΩ and 100kΩ 1% resistors) and batteries in a box but plan to update it so it can be run from an external 5V supply to support longer collection periods. As the input impedence is around 1MΩ the load on the battery is <20μA so recording should have no significant effect on thr battery discharge.

A comparison with another Enyaq would be interesting.

Those wild excursions are quite odd, pushing voltages up to 16v+ isnt going to be doing the battery any good?

I would agree but I am not yet convinced that they reflect the voltage at the battery. I was using a test lash up at the time they were recording and it is possible that they were artifacts of the way it was connected. I have not seen any evidence that the battery was exposed to it.