Leaving the car for most of February

[shinyrobot]

I've abandoned mine for all of December below 40%. No stress. If was fine.

 

[Jto]

Can anyone suggest the optimum charge to leave on the battery if the car is going to sit on the driveway unused for most of February?
Thanks

Hi
Could use something like this.

 

[Odin]

There you go. for more than 1 month disconnect negative terminal, page 291

Note: It is recommended to ensure the vehicle is
placed in READY mode for half an hour every week
to help extend the service life of the battery. If the
vehicle is stored for more than 1 month, remove the
negative terminal from the battery. Make sure that
the vehicle power system has been turned off before
connecting or disconnecting the negative terminal.

From a personal perspective,

For the Love of all that is Holy Don't disconnect the battery....

I did it to install the battery bag cover which is a relatively easy thing to do (not including the absolute pain in the neck of trying to get the pins to engage with the battery bracket because the bag makes the battery bigger).

Once I had reconnected the battery leads and started the car..
It was a display of Horrors and Flashing Warnings and Mayhem Every fault in the World appeared to be happening at the same time.

Once it had sort of settled down it started to be interesting.. Lol..
The driver display brought up a menu that basically demanded that I lower the driver's window "To Activate it" the window went down in stages to the fully lowered position and then I had to raise it again it was in stages.
Next it was the front passenger window, then the driver side passenger, and then the passenger side rear window and each of them were lowered and raised in stages.
It then stated that they were "Activated" and they worked normally.
Now we have to sort out the Steering Wheel.. I had to drive it so I could get a full lock in each direction and it had to be moving (so I couldn't just turn it both ways.
There were more things to do but I think that you can see the picture.
You couldn't make This stuff up..

All in all that took about half an hour and that was at home. Can you imagine having to do it when you have just got back from a long flight and you and your family are tired and just want to get home..

It may just be my car (MG4 long Range Trophy no rear wiper and no middle rear headrest) so I'm not sure what version of it I have, in the UK.

Anyway that's my experience of removing the battery..
I think that I should call it "Christine" Lol..

 

[Chequers]

Hi
Could use something like this.

Popular with Toyota corolla owners because the Corolla dials home checking for updates too much.

 

[RP67]

Left ours at Canberra airport for 6 weeks after driving to the city (70km). Battery was about 70% when we let it, lost 12% in 6 weeks, 12V battery was fine.
I have a jump starter but don’t usually carry it with me.

So the HV battery maintained the charge of the 12V battery. Great. I'm not sure how the jump starter could be useful, but you might need to find out what caused the drain on the 12V battery (frequent check on the vehicle status on your phone, glove compartment light...). Did you make it home/to the charger?

 

[Philz]

So the HV battery maintained the charge of the 12V battery. Great. I'm not sure how the jump starter could be useful, but you might need to find out what caused the drain on the 12V battery (frequent check on the vehicle status on your phone, glove compartment light...). Did you make it home/to the charger?

I assumed the 2% drop per week maintained the 12v charge…car worked perfectly on the drive home. My BIL knows a Tesla owner who couldn’t start his car after a similar time parked.

 

[tsedge]

I just got back from 2 full weeks away with the car left through the 2 coldest weeks (consistently negative temperatures).

Left it with 80%, on return it had 79%. No problems at all with 12V and this is the same experience I've had before at other warmer times of year, it seems to lose about 1% over two weeks.

 

[Kithmo]

I don't touch my Morris Minor for months on end so I just leave the 12v disconnected and it starts fine on reconnecting.
I would think that the 4's 12v should be ok for a month as long as it's not low to start with.

 

[RP67]

I assumed the 2% drop per week maintained the 12v charge…car worked perfectly on the drive home. My BIL knows a Tesla owner who couldn’t start his car after a similar time parked.

As long you happy with the result is fine, I guess it would be different if you couldn't leave the airport. Also I'm not sure whether a 6W/h average consumption is high or not, probably some expert out there to tell us. One thing for sure, I wouldn't leave my car behind lower than 70% SOC for an extended period, just like you did. Trickle charger? No.

 

[Rolfe]

I left mine at 69% for slightly over two weeks. When I got back it was still on 69% and started immediately.

 

[Ian Key]

@tsedge 1% loss could be down to the cold weather. The battery would be warm after the drive to the airport and the loss is when the battery cooled down to the ambient cold temperature.

 

[Tuareg]

I wonder how much gas/petrol evaporates through the gas cap breather of an ICE when it's left for periods of a month or more? This won't be noticeable because of the way ICE's fuel gauges display the level. If they displayed a percentage as on EVs I think ICE owners would be very surprised to see the level drop over time as it certainly does.

If an EV simply had a 4/6/8 bar gauge as on ICEs, the drop wouldn't be noticed.

 

[tsedge]

@tsedge 1% loss could be down to the cold weather. The battery would be warm after the drive to the airport and the loss is when the battery cooled down to the ambient cold temperature.

It was only a short drive from hotel nearby, so I don't think the battery had time to warm up.

 

[Kithmo]

I wonder how much gas/petrol evaporates through the gas cap breather of an ICE when it's left for periods of a month or more? This won't be noticeable because of the way ICE's fuel gauges display the level. If they displayed a percentage as on EVs I think ICE owners would be very surprised to see the level drop over time as it certainly does.

If an EV simply had a 4/6/8 bar gauge as on ICEs, the drop wouldn't be noticed.

Modern cars don't have cap breather as such so the fuel doesn't evaporate, but petrol does go off if left for a long time.

 

[Rolfe]

Like two years plus...

 

[tsedge]

Petrol goes off between 3 to 6 months, diesel is good for 6 months to a year.

Older than that and the fuels will degrade somewhat, especially the more recent Ethanol-rich petrol variants, although may still be usable, but it is recommended to drain the fuel system if leaving a car for a long time.

 

[Coulomb]

If an EV simply had a 4/6/8 bar gauge as on ICEs, the drop wouldn't be noticed.

My EV has an 8 bar gauge (8 LED). It's an MG ZS EV Mark 1. I can get a SoC estimate with 1% resolution, but I have to be charging the car to see it. Just another niggle .

I didn't know that ICE cars were made that crude; I haven't paid attention to them for years. I do think that the ICE trick of "saving" the fuel level even with the power totally off is pretty neat.

Edit: And my other EV (Nissan Leaf 2012) has a 12-bar fuel gauge. Such precision! It's certainly more precise than the Guess O Meter (range estimate), after the first two years of a warranty replacement battery (it's now 4.5 years since the battery was replaced/refurbished).

 

[Rolfe]

I had a chat with my neighbour, an RAC patrolman, about this, in relation to my motorbike. He said about two years for petrol, and my experiences with the motorbike, and with petrol kept in a plastic can, bear this out.

 

[WonkoTheSaneUK]

I assumed the 2% drop per week maintained the 12v charge…car worked perfectly on the drive home. My BIL knows a Tesla owner who couldn’t start his car after a similar time parked.

Sounds like the Tesla owner left "Sentry Mode" (which runs all 8 onboard cameras) running while he was away.

 

[Rolfe]

Saw a video a few days ago where a Tesla caught fire. Owner went to the police alleging arson. Police said no, "everybody knows" Teslas just catch fire spontaneously. But the sentry mode revealed someone pouring petrol over the car (and into it) and setting light to it.