Optimised battery use on/off

[Trilby]

My google skills are evading me, it was asked on spealev.com but with no real answer....
What does this switch do?

[Big_GT]

Allows the main traction battery to keep the 12v battery topped up if you use the app a lot to communicate with the car.

[sidehaas]

Allows the main traction battery to keep the 12v battery topped up if you use the app a lot to communicate with the car.

I believe the main battery will top up the 12 V anyway unless you have a car on a very early software version (1.0 I think). However, even though the 12V is being topped up, the car has a software energy 'budget' for remote functions, and won't let them operate if it is used up until the car ignition is turned on again. The optimised battery use function removes those budgets so that the functions can continue to be used at the cost of more topping up. Personally I never reached the budgets before having this option (it only existed from 3.0) even though I make regular use of the app.

[Big_GT]

Allows the main traction battery to keep the 12v battery topped up if you use the app a lot to communicate with the car.

I believe the main battery will top up the 12 V anyway unless you have a car on a very early software version (1.0 I think). However, even though the 12V is being topped up, the car has a software energy 'budget' for remote functions, and won't let them operate if it is used up until the car ignition is turned on again. The optimised battery use function removes those budgets so that the functions can continue to be used at the cost of more topping up. Personally I never reached the budgets before having this option (it only existed from 3.0) even though I make regular use of the app.

From testing and using OBD and car scanner, I’ve discovered that with optimisation off on my 3.2 car - the 12v battery only seems to recharge if connected to ac or ignition is on, I’ve even sat in passenger seat on ccs charging and notice 30 mins had passed and the 12v battery was dropping, as soon as I sat in drivers seat voltage went up to 13.9v, with the optimisation turned on if I queried the app for charge status after 6 times over an hour I hear the HV battery engage, I also noted that if you have charging locations on all the above was different and setting the car up to charge at home etc was just not worth the hassle to keep investigating - I use Ohme for home charging and it’s simple. I might experiment again in winter when 12v demands are higher.

[Big_GT]

another observation, if I turn battery optimisation off over night, when I use the car the next day at some point during the next journey I get the " new settings are available ", I'd love to be able to see VW literature on logic of their software and what in their view the car is supposed to do.

[sidehaas]

Allows the main traction battery to keep the 12v battery topped up if you use the app a lot to communicate with the car.

I believe the main battery will top up the 12 V anyway unless you have a car on a very early software version (1.0 I think). However, even though the 12V is being topped up, the car has a software energy 'budget' for remote functions, and won't let them operate if it is used up until the car ignition is turned on again. The optimised battery use function removes those budgets so that the functions can continue to be used at the cost of more topping up. Personally I never reached the budgets before having this option (it only existed from 3.0) even though I make regular use of the app.

From testing and using OBD and car scanner, I’ve discovered that with optimisation off on my 3.2 car - the 12v battery only seems to recharge if connected to ac or ignition is on, I’ve even sat in passenger seat on ccs charging and notice 30 mins had passed and the 12v battery was dropping, as soon as I sat in drivers seat voltage went up to 13.9v, with the optimisation turned on if I queried the app for charge status after 6 times over an hour I hear the HV battery engage, I also noted that if you have charging locations on all the above was different and setting the car up to charge at home etc was just not worth the hassle to keep investigating - I use Ohme for home charging and it’s simple. I might experiment again in winter when 12v demands are higher.

Interesting, thanks. I know there were significant 12V problems in early ID3s and that when 2.0 (I think - might have been 2.1) came along it was supposed to have resolved the issue by automatically topping up the 12V from the main battery. The problems certainly became far less frequent.
The explanation I gave above for the optimised battery use setting on 3.0 came originally from a guy on the meinID forum in Germany who seems to have a lot of trust as a VW employee who knows a lot about the car's but posts anonymously. Your data would suggest it's inaccurate, unless the HV battery only cuts in once the 12V battery reaches a lower level than yours dud while monitoring. I guess it's also possible that 3.0 without that option selected behaves differently from 2.3/4. Personally I've never seen either (1) any 12V problems with 2.3 or (2) any loss of SoC with 3.0 and that option switched on.

[Big_GT]

I believe the main battery will top up the 12 V anyway unless you have a car on a very early software version (1.0 I think). However, even though the 12V is being topped up, the car has a software energy 'budget' for remote functions, and won't let them operate if it is used up until the car ignition is turned on again. The optimised battery use function removes those budgets so that the functions can continue to be used at the cost of more topping up. Personally I never reached the budgets before having this option (it only existed from 3.0) even though I make regular use of the app.

From testing and using OBD and car scanner, I’ve discovered that with optimisation off on my 3.2 car - the 12v battery only seems to recharge if connected to ac or ignition is on, I’ve even sat in passenger seat on ccs charging and notice 30 mins had passed and the 12v battery was dropping, as soon as I sat in drivers seat voltage went up to 13.9v, with the optimisation turned on if I queried the app for charge status after 6 times over an hour I hear the HV battery engage, I also noted that if you have charging locations on all the above was different and setting the car up to charge at home etc was just not worth the hassle to keep investigating - I use Ohme for home charging and it’s simple. I might experiment again in winter when 12v demands are higher.

Interesting, thanks. I know there were significant 12V problems in early ID3s and that when 2.0 (I think - might have been 2.1) came along it was supposed to have resolved the issue by automatically topping up the 12V from the main battery. The problems certainly became far less frequent.
The explanation I gave above for the optimised battery use setting on 3.0 came originally from a guy on the meinID forum in Germany who seems to have a lot of trust as a VW employee who knows a lot about the car's but posts anonymously. Your data would suggest it's inaccurate, unless the HV battery only cuts in once the 12V battery reaches a lower level than yours dud while monitoring. I guess it's also possible that 3.0 without that option selected behaves differently from 2.3/4. Personally I've never seen either (1) any 12V problems with 2.3 or (2) any loss of SoC with 3.0 and that option switched on.

These cars are very interesting from a consistency view point, a friend on FB his car was parked whilst he was away on holiday, MY23 Max on 3.2 and he returned to a dead 12v battery, but the traction battery was well above what would be classed as low state of charge. This would indicate that the car had not monitored the 12v drop, yet he had optimisation on but I don't think used the app when away.

EV's and their Software do fascinate me and the seemingly lacklustre approach to basic redundancy. It's def not VW specific, Hyundai/Kia have real issues with 12v side of things.

[G43FAN]

What is the car doing to flatten the 12v battery? This isn't really an EV thing, the 12volt battery is there to support the same systems it does in an ICE car, I wouldn't expect to go on holiday and come back to a flat battery in any car less than 5 years old. Your ICE car doesn't run it's engine for a few minutes whenever the 12v is getting low, so why should the EV? (maybe the other car forums are full of ICE cars with flat batteries I haven't looked)

[sidehaas]

From testing and using OBD and car scanner, I’ve discovered that with optimisation off on my 3.2 car - the 12v battery only seems to recharge if connected to ac or ignition is on, I’ve even sat in passenger seat on ccs charging and notice 30 mins had passed and the 12v battery was dropping, as soon as I sat in drivers seat voltage went up to 13.9v, with the optimisation turned on if I queried the app for charge status after 6 times over an hour I hear the HV battery engage, I also noted that if you have charging locations on all the above was different and setting the car up to charge at home etc was just not worth the hassle to keep investigating - I use Ohme for home charging and it’s simple. I might experiment again in winter when 12v demands are higher.

Interesting, thanks. I know there were significant 12V problems in early ID3s and that when 2.0 (I think - might have been 2.1) came along it was supposed to have resolved the issue by automatically topping up the 12V from the main battery. The problems certainly became far less frequent.
The explanation I gave above for the optimised battery use setting on 3.0 came originally from a guy on the meinID forum in Germany who seems to have a lot of trust as a VW employee who knows a lot about the car's but posts anonymously. Your data would suggest it's inaccurate, unless the HV battery only cuts in once the 12V battery reaches a lower level than yours dud while monitoring. I guess it's also possible that 3.0 without that option selected behaves differently from 2.3/4. Personally I've never seen either (1) any 12V problems with 2.3 or (2) any loss of SoC with 3.0 and that option switched on.

These cars are very interesting from a consistency view point, a friend on FB his car was parked whilst he was away on holiday, MY23 Max on 3.2 and he returned to a dead 12v battery, but the traction battery was well above what would be classed as low state of charge. This would indicate that the car had not monitored the 12v drop, yet he had optimisation on but I don't think used the app when away.

EV's and their Software do fascinate me and the seemingly lacklustre approach to basic redundancy. It's def not VW specific, Hyundai/Kia have real issues with 12v side of things.

If the 12V battery runs flat the car has a fault, I'm sure about that.

[Trilby]

Some really interesting comments here thanks folks.

I’m still not sure what effect the button might have. I open the app once or twice a day and after a few moments it seems to update the data ok with that switch off (when I am logged in to they car!)

I’ll leave it off for now

[TimF]

Interesting, thanks. I know there were significant 12V problems in early ID3s and that when 2.0 (I think - might have been 2.1) came along it was supposed to have resolved the issue by automatically topping up the 12V from the main battery. The problems certainly became far less frequent.
The explanation I gave above for the optimised battery use setting on 3.0 came originally from a guy on the meinID forum in Germany who seems to have a lot of trust as a VW employee who knows a lot about the car's but posts anonymously. Your data would suggest it's inaccurate, unless the HV battery only cuts in once the 12V battery reaches a lower level than yours dud while monitoring. I guess it's also possible that 3.0 without that option selected behaves differently from 2.3/4. Personally I've never seen either (1) any 12V problems with 2.3 or (2) any loss of SoC with 3.0 and that option switched on.

These cars are very interesting from a consistency view point, a friend on FB his car was parked whilst he was away on holiday, MY23 Max on 3.2 and he returned to a dead 12v battery, but the traction battery was well above what would be classed as low state of charge. This would indicate that the car had not monitored the 12v drop, yet he had optimisation on but I don't think used the app when away.

EV's and their Software do fascinate me and the seemingly lacklustre approach to basic redundancy. It's def not VW specific, Hyundai/Kia have real issues with 12v side of things.

If the 12V battery runs flat the car has a fault, I'm sure about that.

According to my local workshop, the fault which flattens the 12V battery lies purely with a malfunctioning owner. I quote: "the 12V battery is only charged WHEN THE CAR IS MOVING" (my emphasis). Also: "you don't do enough mileage". Quite what the Optimised Battery Care (or whatever its silly title is) does do I'm not at all sure - nor was the service manager. It must do something, and the nagging to enable it after upgrading to V3 was most insistent (if it's that critical why could it be disabled?) The service manager also told me that the recall to replace the 12V battery was to swap to one with a 20% LOWER capacity. I know the chemistry was changed, and there was something about better cycling, but I had no 12V problems until some months after the swap.

[sidehaas]

These cars are very interesting from a consistency view point, a friend on FB his car was parked whilst he was away on holiday, MY23 Max on 3.2 and he returned to a dead 12v battery, but the traction battery was well above what would be classed as low state of charge. This would indicate that the car had not monitored the 12v drop, yet he had optimisation on but I don't think used the app when away.

EV's and their Software do fascinate me and the seemingly lacklustre approach to basic redundancy. It's def not VW specific, Hyundai/Kia have real issues with 12v side of things.

If the 12V battery runs flat the car has a fault, I'm sure about that.

According to my local workshop, the fault which flattens the 12V battery lies purely with a malfunctioning owner. I quote: "the 12V battery is only charged WHEN THE CAR IS MOVING" (my emphasis). Also: "you don't do enough mileage". Quite what the Optimised Battery Care (or whatever its silly title is) does do I'm not at all sure - nor was the service manager. It must do something, and the nagging to enable it after upgrading to V3 was most insistent (if it's that critical why could it be disabled?) The service manager also told me that the recall to replace the 12V battery was to swap to one with a 20% LOWER capacity. I know the chemistry was changed, and there was something about better cycling, but I had no 12V problems until some months after the swap.

Your dealer is clearly clueless.

[TimF]

If the 12V battery runs flat the car has a fault, I'm sure about that.

According to my local workshop, the fault which flattens the 12V battery lies purely with a malfunctioning owner. I quote: "the 12V battery is only charged WHEN THE CAR IS MOVING" (my emphasis). Also: "you don't do enough mileage". Quite what the Optimised Battery Care (or whatever its silly title is) does do I'm not at all sure - nor was the service manager. It must do something, and the nagging to enable it after upgrading to V3 was most insistent (if it's that critical why could it be disabled?) The service manager also told me that the recall to replace the 12V battery was to swap to one with a 20% LOWER capacity. I know the chemistry was changed, and there was something about better cycling, but I had no 12V problems until some months after the swap.

Your dealer is clearly clueless.

You might think that, I couldn't possibly comment!!!

Challenged to put the low mileage statement in writing, they claim that what they said is that "low mileage might be the cause of the problem". Since they don't fully accept that there is a problem (they haven't seen it, and there is nothing in the car's "fault logs"), it's academic anyway.

I asked if the information could be provided in writing. Allegedly, the "only while the car is moving" condition was to be found "in the manual". All umpteen hundred pages of which is, of course, found within the infotainment system. I've worked through the 2020 pdf which can be found online, and there's nothing in there about this. As yet I haven't looked at it on the car's screen (particularly since doing so while the car was stationary would apparently drain the 12V battery without providing any charging for it). Later, I was told it wasn't quite as had been said. Apparently, according to their manual, the "RX1" module will only provide charging while the vehicle is "in use", without any indication of what classes of "use" are sufficient.

I'm still baffled that a piece of kit with a 58kWh battery, whose health, security and other functions are monitored 24/7 by systems powered from a battery of a couple of hundred Wh capacity does not have a standard feature whereby if the 12V battery charge drops below a given level, the 400V battery is enabled to give the 12V battery a boost. It's clear that there is a heirarchy of 12V functions which are disabled in turn as the 12V battery charge declines, but it seems none of those functions includes recharging the source for all of them.

[sidehaas]

According to my local workshop, the fault which flattens the 12V battery lies purely with a malfunctioning owner. I quote: "the 12V battery is only charged WHEN THE CAR IS MOVING" (my emphasis). Also: "you don't do enough mileage". Quite what the Optimised Battery Care (or whatever its silly title is) does do I'm not at all sure - nor was the service manager. It must do something, and the nagging to enable it after upgrading to V3 was most insistent (if it's that critical why could it be disabled?) The service manager also told me that the recall to replace the 12V battery was to swap to one with a 20% LOWER capacity. I know the chemistry was changed, and there was something about better cycling, but I had no 12V problems until some months after the swap.

Your dealer is clearly clueless.

You might think that, I couldn't possibly comment!!!

Challenged to put the low mileage statement in writing, they claim that what they said is that "low mileage might be the cause of the problem". Since they don't fully accept that there is a problem (they haven't seen it, and there is nothing in the car's "fault logs"), it's academic anyway.

I asked if the information could be provided in writing. Allegedly, the "only while the car is moving" condition was to be found "in the manual". All umpteen hundred pages of which is, of course, found within the infotainment system. I've worked through the 2020 pdf which can be found online, and there's nothing in there about this. As yet I haven't looked at it on the car's screen (particularly since doing so while the car was stationary would apparently drain the 12V battery without providing any charging for it). Later, I was told it wasn't quite as had been said. Apparently, according to their manual, the "RX1" module will only provide charging while the vehicle is "in use", without any indication of what classes of "use" are sufficient.

I'm still baffled that a piece of kit with a 58kWh battery, whose health, security and other functions are monitored 24/7 by systems powered from a battery of a couple of hundred Wh capacity does not have a standard feature whereby if the 12V battery charge drops below a given level, the 400V battery is enabled to give the 12V battery a boost. It's clear that there is a heirarchy of 12V functions which are disabled in turn as the 12V battery charge declines, but it seems none of those functions includes recharging the source for all of them.

The 12 V is topped up by the main battery. I have seen graphs people have shared online who had monitored their battery voltage while the car was off and you can see it being topped up. With optimised battery usage on it does it more often. But even before that option became available before 3.0, I believe it still did it to some extent - except on the very earliest software the cars came with (1.0, maybe 2.0?) which is why there were lots of 12V battery failures in the first few months after the car came out. Thankfully they are now pretty rare.
If you have the option I would get an opinion from a different dealer. I know that's not always convenient

[the.kes]

another observation, if I turn battery optimisation off over night, when I use the car the next day at some point during the next journey I get the " new settings are available ", I'd love to be able to see VW literature on logic of their software and what in their view the car is supposed to do.

They have not got one, they have no better idea of software logic than a camel in the Sahara.

[ChrisT]

My google skills are evading me, it was asked on spealev.com but with no real answer....
What does this switch do?
IMG_8425.jpg

If you think of an internal combustion car, the engine charges the battery using the alternator while the car is running. If you don’t use the car for long periods of time the 12 volt battery slowly drains down for a number of reasons. The optimise battery use option in an electric car allows you to use your big high voltage battery that drive your car to charge the smaller 12 volt battery which keeps the car operational. If you leave the car for long periods of time without using it, it will slowly run down your big high voltage battery which will impact the cars range. If you use the car frequently then the 12 volt battery gets charged up during your journey. I’d personally turn the optimise battery use on, then your sure your car will “wake up” when you return to your car. If you are going to leave your car for long periods of time, ensure your big high voltage battery is around 50% charged and you won’t have any problems
Cheers
Chris

[TimF]

... If you are going to leave your car for long periods of time, ensure your big high voltage battery is around 50% charged and you won’t have any problems

If only. Apparently, a couple of weeks counts as a "long time" where my car is concerned - even with optimised battery use (etc) enabled.

Yesterday, when I got in the car a message flashed on the cockpit display for a few seconds saying something like "12V battery will only charge while the vehicle is in motion". Which is not true, as it does charge while stationary, even with the drive not enabled. But although the permanently-operating systems (eg security alarm, check for key in range) include one which monitors the 12V battery status (which tells the server it won't be able to synchronise for updating status in the app), that doesn't then wake up the HV battery to recharge the 12V one. Nuts, IMO.

[sidehaas]

... If you are going to leave your car for long periods of time, ensure your big high voltage battery is around 50% charged and you won’t have any problems

If only. Apparently, a couple of weeks counts as a "long time" where my car is concerned - even with optimised battery use (etc) enabled.

Yesterday, when I got in the car a message flashed on the cockpit display for a few seconds saying something like "12V battery will only charge while the vehicle is in motion". Which is not true, as it does charge while stationary, even with the drive not enabled. But although the permanently-operating systems (eg security alarm, check for key in range) include one which monitors the 12V battery status (which tells the server it won't be able to synchronise for updating status in the app), that doesn't then wake up the HV battery to recharge the 12V one. Nuts, IMO.

I believe it does if things are working correctly.

[TimF]

... If you are going to leave your car for long periods of time, ensure your big high voltage battery is around 50% charged and you won’t have any problems

If only. Apparently, a couple of weeks counts as a "long time" where my car is concerned - even with optimised battery use (etc) enabled.

Yesterday, when I got in the car a message flashed on the cockpit display for a few seconds saying something like "12V battery will only charge while the vehicle is in motion". Which is not true, as it does charge while stationary, even with the drive not enabled. But although the permanently-operating systems (eg security alarm, check for key in range) include one which monitors the 12V battery status (which tells the server it won't be able to synchronise for updating status in the app), that doesn't then wake up the HV battery to recharge the 12V one. Nuts, IMO.

I believe it does if things are working correctly.

I agree. Dealer doesn't.

[Kwr68]

Seems to me there could a fault some where although the 12v is no different to any other car short trips do not keep the battery charged or there is a fault with the battery . I drove from Colchester to Birmingham airport so had a good run ,left on 84% for nearly 2 weeks in February cold weather came back mid evening the was as i left it drove off no problems.