Buying a used EV today - beware.

Petriix

!!!!!!... Teslas aren't all EVs. It's well known that Teslas run a whole bunch of ancillary systems which deplete the battery. I could leave my MG5 for several months without any issues.

If remaining unused for an extended period of time, simply turning it on for 30 minutes every few weeks will keep the 12v battery charged. The HV battery will be fine if left between 40-80% charged, otherwise there might be a tiny amount of additional degradation - likely unmeasurable but would add up over time.

Grumpy_chap

Petriix said:

 Teslas aren't all EVs. 

Yes they are.

JKenH

Here is a summary of manufacturers recommendations for long term storage of cars with some specific instructions for EVs. 

Several manufacturers specifically state that allowing the battery to discharge to zero can be damaging. Some give specific instructions as to the state of charge the vehicle should be left at but the recommendations aren’t the same for all vehicles/manufacturers. 

https://www.autovolt-magazine.com/how-to-park-your-ev-for-long-periods-manufacturer-guidance/

Some recommend they be left plugged in while other don’t. Some say leave fully charged, others between 40% and 60%. It is a bit of a minefield and unlikely that dealers will be au fait with specific requirements for every brand. 

The general advice is not to leave the vehicle at low levels of charge which could easily happen if an EV has been driven to a garage to be traded in and not subsequently charged. 

[Deleted User]

Depends if the car was properly turned off or not. When properly turned off they can sit for a long time without problems, if the battery wasn't too low to start with.

Teslas are badly designed and the software is poor. Not all EVs have this issue, at just not this severely.

ontheroad1970

Grumpy_chap said:

Petriix said:

 Teslas aren't all EVs. 

Yes they are.

I think he is trying to say that that not all EVs are Teslas.

Petriix

Grumpy_chap said:

Petriix said:

 Teslas aren't all EVs. 

Yes they are.

I should have said 'all EVs'. It was obvious what I meant. I've got minimal interest in Teslas and ultimately think they're pretty irrelevant to most people (who will never afford one). It's very strange to raise a uniquely Tesla issue as if it's universal to all EVs.

ididgetwhereiamtoday

Petriix said:

Grumpy_chap said:

Petriix said:

 Teslas aren't all EVs. 

Yes they are.

I should have said 'all EVs'. It was obvious what I meant. I've got minimal interest in Teslas and ultimately think they're pretty irrelevant to most people (who will never afford one). It's very strange to raise a uniquely Tesla issue as if it's universal to all EVs.

I think in a few years there will be that many Teslas on the used market that they will be more 'affordable' to a lot of people. It looks like Tesla want to be mass market car producers like Ford etc. Used Teslas are already coming through at similar prices to new MGs. 

JKenH

Petriix said:

!!!!!!... Teslas aren't all EVs. It's well known that Teslas run a whole bunch of ancillary systems which deplete the battery. I could leave my MG5 for several months without any issues.

If remaining unused for an extended period of time, simply turning it on for 30 minutes every few weeks will keep the 12v battery charged. The HV battery will be fine if left between 40-80% charged, otherwise there might be a tiny amount of additional degradation - likely unmeasurable but would add up over time.

The thrust of my original post was about Tesla’s which seem to lose charge far more quickly than other cars. I didn’t suggest all cars would be as bad as Tesla’s but urged caution when buying any used EV that migh5 have stood around on a dealers lot for months. 

You say “I could leave my MG5 for several months without any issues.” Do you actually know that or are you just speculating. Would you have no reservations about buying a used MG EV that has stood around for months? Would you not want to try and find out if it has been kept charged as per manufacturers recommendations?

This is the advice from MG (ok, it’s about the ZS EV but might apply to the 5 as well, I don’t know)

MG

ZS EV – The high voltage battery should have a minimum charge of 15% if the car is left to stand.

and from the MG website

How to make your car battery last longer

There are several tips that you can use to try and increase your electric car battery life:

- Charge the electric car battery between 20%-80% - The lifespan of the battery pack often depends on how much it’s charged. You can extend the life of the batteries by only charging them between 20% and 80% and trying not to let them drop below 50% too often. Going beyond these limits can increase the rate that the battery deteriorates over time.

https://www.mg.co.uk/electric-life/guide-electric-car-battery-life

i am sure you will look after your MG battery in line with the recommendations and cautions above but imagine someone trading their car in. If, the previous night, the car has enough range to get to the garage I doubt the owner would top the battery up anymore than he would top the petrol tank up. The car could arrive at the garage with 15% charge or less. It could then sit for months. No matter how good the tech is on the MGEVs there will be some loss of charge. Even if it is only of a similar order to my Nissan Leaf at 1% per month it will go down, albeit very slowly. It could get down to a critical level.

This thread isn’t about your whether your MG5 loses any measurable charge overnight, it is about EVs potentially sitting for months at very low states of charge. It won’t be all of them, it might only be a small percentage of them but if you are unlucky enough to buy one of those EVs that has sat for several months with its HV battery at a low state of charge you might be buying a load of trouble. 

I am more than happy for you to post your own experience. People may take comfort from that. I think though it would be wrong to dismiss all concerns about buying a used EV that has stood around for a few months solely on the basis of your experience keeping your car charged as per manufacturer’s recommendations. 

JKenH

Petriix said:

Grumpy_chap said:

Petriix said:

 Teslas aren't all EVs. 

Yes they are.

I should have said 'all EVs'. It was obvious what I meant. I've got minimal interest in Teslas and ultimately think they're pretty irrelevant to most people (who will never afford one). It's very strange to raise a uniquely Tesla issue as if it's universal to all EVs.

Please see my comments in my post above. The amount of charge lost overnight may be an issue peculiar to Teslas but was the Tesla awaiting repair experience that made me think about cars sitting around at low states of charge on dealers’ lots. That is the issue potentially universal to all EVs. 

I do also think it’s wrong to dismiss Teslas as irrelevant to most people. They are by far the most populous EVs on the road today and given the used prices are now not much more than cheaper cars like MGs it is inevitable that they will figure in people’s thoughts when shopping for a used EV. (Ok, I will concede, maybe not in yours)

JKenH

ididgetwhereiamtoday said:

Petriix said:

Grumpy_chap said:

Petriix said:

 Teslas aren't all EVs. 

Yes they are.

I should have said 'all EVs'. It was obvious what I meant. I've got minimal interest in Teslas and ultimately think they're pretty irrelevant to most people (who will never afford one). It's very strange to raise a uniquely Tesla issue as if it's universal to all EVs.

I think in a few years there will be that many Teslas on the used market that they will be more 'affordable' to a lot of people. It looks like Tesla want to be mass market car producers like Ford etc. Used Teslas are already coming through at similar prices to new MGs. 

…and in far larger volumes.

Edit: actually the volumes are far closer than I realised. There are 1115 MG EVs for sale on AutoTrader (2019 to 2022 inclusive) and (1175 Teslas 2019 to 2022 inclusive). The Tesla figure excludes Tesla inventory stock which when included stood at 1810 units for Model 3/Y. 

Strange, I can’t recall having seen an MG4 on the road yet.