12v Charging

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Location (town/city + country)
Bristol, UK
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IM5
Charging the 12v battery:-
I know you have to have the car in "Ready" mode for 30minutes or more, but is there any way of leaving the car whilst in that mode?
I'm not using the car much for a week or three, but even though I'm at home, I don't relish just sitting in the car twiddling my thumbs for half an hour each time. When the car is in "Ready" mode, as soon as you open a door, it leaves that mode of course.
I know the drl's will stay on, but other than climbing out through the boot or using a 12v battery charger, anyone have ideas on how to keep the 12v battery charging off the HE battery with no one in the car?
 
Put the car on charge? The 12V is charged then too.
Well, the SOC is already at 76%, so it won't take too much more charge. I was thinking about using a smart charger, but I'm sure I read that the use of a smart charger can have the opposite effect and actually cause the battery to discharge - although I find that an odd concept!
 
But 30 mins on a wallbox won't put a huge amount of charge into the car (maybe take you to 80% or so) but will still give you 30 mins top up of the 12V battery. :)
I am guessing Sloucher doesn't want to go beyond 80% but yes, this would still help.
 
I am guessing Sloucher doesn't want to go beyond 80% but yes, this would still help.
You're right about not wanting to go much above 80%. Thinking about it, I will have a trip from Bristol to Yeovil and back in just under a week's time, so that will take care of it for now. However, I'm just concerned about in future, bearing in mind the number of owners who've had flat battery problems. Maybe the answer would be a better quality and/or capacity battery.

What about the idea of using a smart trickle charger, is that a possibility, or is it (as I think I've read), not advisable?
 
You're right about not wanting to go much above 80%. Thinking about it, I will have a trip from Bristol to Yeovil and back in just under a week's time, so that will take care of it for now. However, I'm just concerned about in future, bearing in mind the number of owners who've had flat battery problems. Maybe the answer would be a better quality and/or capacity battery.
You could put a spanner and a 12v battery booster in the car as a backup, then if you ever get a problem you can get it restarted to get you home.

You could proactively replace the 12V battery, but that's going to cost for a decent one.
What about the idea of using a smart trickle charger, is that a possibility, or is it (as I think I've read), not advisable?
I don't see why not, it is a standard 12V battery. What you mustn't do is try to jump start an ICE car with your EV.
 
I think the only problem there would be that a discharge adaptor (I assume you mean V2L?) can't be plugged in at the same time as the charging lead.
You don’t need the charging lead in place to charge the 12v from the traction battery. The car can be locked whilst in discharge mode so no need to sit with it
 
You don’t need the charging lead in place to charge the 12v from the traction battery. The car can be locked whilst in discharge mode so no need to sit with it
Ah, so are you are proposing that if I apply a load via V2L, then the 12v battery would be charged from the HE battery?
My reason for querying that is that the manual specifically states that the car has to be in "READY" mode in order for the 12v battery to charge, but also states "During discharge, the vehicle cannot be placed in “READY” mode."
Methinks some experimentation needs to be carried out!
 
Pretty sure that is the case as the car is powered up when discharging so the 12v must be kept charged otherwise it would flatten pretty quickly when using V2L for any length of time
Not sure that follows: V2L operates through the inverter from the HE battery. Sloucher is right, we need to experiment. If I have time at the weekend, I might try it myself.
 
Surely the simplest solution is to buy a jump starter power pack just in case the 12v battery does discharge and not to keep checking it on the app to wake it up.
That might be the simplest solution, but I'd rather preventative maintenance than demonstrate another ev and MG4 failing to ice zealots!!
 
Not sure that follows: V2L operates through the inverter from the HE battery. Sloucher is right, we need to experiment. If I have time at the weekend, I might try it myself
I think @Tig170 confirmed on another thread that the 12v is charged during discharge as can be seen on the app
 
I'd like to confirm one way, or the other, by using the app, but that waste of space got uninstalled from my phone. Worst constructed app I have ever come across, it never works even when stood next to the car outside the house within 10 feet of the router!
Can anyone remind me how to view the 12v status from the in-car system?
 
I'd like to confirm one way, or the other, by using the app, but that waste of space got uninstalled from my phone. Worst constructed app I have ever come across, it never works even when stood next to the car outside the house within 10 feet of the router!
Can anyone remind me how to view the 12v status from the in-car system?
If I remember correctly, it can be see in the drivers display ?
 

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