Buying a used EV today - beware.

JKenH

@Petriix will be pleased to note that the MG range are among the fastest selling EVs. (October data latest  I can find).

MG has three models in the Top 10 Fastest Selling Used EV  charts, reflecting its strong EV sales performance in 2022.

The fastest selling car in the September plate-change was the Kia EV6, which sold in 19 days. This was followed by the MG ZS, which shifted off forecourts in 20 days, acdording to Auto Trader data.

The Volkswagen e-Golf and MG MG5 took 21 days to retail while the Hyundai IONIQ 5 and Vauxhall Corsa-e sold in 25 days.

https://www.motortrader.com/motor-trader-news/automotive-news/check-fastest-selling-evs-auto-trader-25-10-2022

Herzlos

I'd be worried about any car that's been sat for months on a forecourt. It's especially bad for diesels with DPFs given they'll be fired up for a very short time to shuffle it 50ft across the yard and then off again for a week. 

I'd also hope that any decent dealer would keep the cars in a usable state so that if someone came in to see it they could at least get in and turn it on.
I've seen plenty of cars with trickle chargers on at dealers, but also plenty with completely flat tyres so it's a very mixed bag.

Of course there's also nothing to say that said car hadn't been sat on a driveway for 6 months before being sold into the trade. Or that the previous owner didn't let the battery run virtually flat on a regular basis either.

This does seem to be a predominantly Tesla thing, as they seem to be doing a lot even when off. Tesla may be highest profile EV for now but the new sales data is showing that won't be the case for long.

Is there any way to meaningfully test the battery condition before buying?

prowla

So, don't leave an EV uncharged for ~3 months.

Typhoon2000

So when MG or other manufacturers quote the range of cars per charge, are they quoting 0-100% or 20-80%?
Advice about not letting the battery drop below 50% often is also a bit worrying if they re suggesting that to maintain battery life you pr driving range between charges is 30% of battery capacity (80%-50%).

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

JKenH

Herzlos said:

I'd be worried about any car that's been sat for months on a forecourt. It's especially bad for diesels with DPFs given they'll be fired up for a very short time to shuffle it 50ft across the yard and then off again for a week. 

I'd also hope that any decent dealer would keep the cars in a usable state so that if someone came in to see it they could at least get in and turn it on.
I've seen plenty of cars with trickle chargers on at dealers, but also plenty with completely flat tyres so it's a very mixed bag.

Of course there's also nothing to say that said car hadn't been sat on a driveway for 6 months before being sold into the trade. Or that the previous owner didn't let the battery run virtually flat on a regular basis either.

This does seem to be a predominantly Tesla thing, as they seem to be doing a lot even when off. Tesla may be highest profile EV for now but the new sales data is showing that won't be the case for long.

Is there any way to meaningfully test the battery condition before buying?

When I bought my (petrol) Golf in October I stopped on the test drive after a couple of miles to phone my wife. I turned the ignition off, as one should, and then it wouldn’t restart - the battery was completely dead. The salesman had to come out and jump start the car. At least I got a brand new battery and new discs and pads all round as they were too rusty for the MoT and a new Michelin tyre as it had an odd budget tyre on one corner.

That is the same garage that is selling the 3 Teslas I have been following. (I saw them when I bought my Golf, hence the interest. I actually had a chat to the salesman about them but that’s another story). It is a well regarded, award winning, garage but has over 400 cars in stock. I imagine it is quite difficult keeping all the cars in the lot charged. The salesman said to me that the cars are all left unlocked so customers can browse at their leisure and that’s why the batteries go flat. Apparently, this is true, at least according to this source.

Leaving your doors unlocked can drain the battery? Believe it or not, yes. Many cars will run readiness checks at set intervals whenever the car doors are unlocked. These readiness checks use power from the battery, which ultimately drains it. 

https://powertronbatteryco.com/5-unexpected-things-can-help-car-battery-problems/

Not all car dealers leave their stock unlocked. This particular dealer has a high palisade fence round the entire site including the showroom and 2 gates between where the stock is parked and the road, so presumably they believe it is safe to do leave their cars unlocked, even if not great for the batteries. The BMW dealer opposite has an open frontage so punters can walk round anytime day or night so I imagine their cars will be locked all the time. 

I am not saying all EVs sitting on dealer forecourts will have flat batteries, it’s just something to be aware of. 

As to whether you can test the battery condition will vary from manufacturer to manufacturer and possibly model to model. I only have experience of the Nissan Leaf. If you have the right app on your phone - I used to use LeafSpy you can plug an OBD dongle into the OBD2 port and access data about the battery. 

Here is a screenshot of the first page(screen) of 5 that are accessible. (Other screens provide other data). You can see from this screen the State of Health (SoH) of the battery measured as a percentage and perhaps more importantly the condition of the cells which are nicely balanced. If you know what to expect you can make sense of the other figures such as AHr and V. You can also see how many times the car has been plugged into a DC charger (rapid charged) and a level 1/2 charger (home charged). In this case (my old Leaf/now my son’s car) the number of DC charges is quite high because he has a V2H set up at home which DC charges his car at 6kW rather than the usual AC 7kW home charger. 

In the first photo the car is almost 3 years old and has done 18k miles. The battery SoH is now 92.31% but in the second photo taken in May 2021 when the car had done 6k miles and was 14 months old the battery SoH is showing as 93.87%. (Note the cell voltages are higher at 18k miles than 6k miles but I wonder if this is a function of the higher battery temperature).

Worryingly the Leaf appears to suffer significant degradation (about 5% from around 99% when new) in the first year and it then levels off. This isn’t necessarily the true SoH of the battery- just what the BMS is saying. Nissan do BMS updates from time to time and in the 30kWh Leafs this can result in the SoH improving from around 75% to around 90% with a commensurate increase in range. 

I should also explain here that the 24 and 30kWh Leafs had a display in the dashboard which gave an indication of the SoH of the battery in terms of a number of bars. A new Leaf has 12 bars and when the SoH drops to 85% the first bar disappears and then they go more quickly after that. The last BMS update on our 30kWh Leaf reinstated the missing bars as well as taking the SoH back up to over 91%. If you have LeafSpy you can check if the car has had the latest BMS update. The 40kWh Leaf has just a long bar with no intermediate gradations so is virtu useless as means of checking battery heath.

You will need to ask the owner/dealer’s permission before removing the trim panel to access the OBD port.

I know there is an app for Teslas although I believe the OBD port is more difficult to access. (Tesla do things differently to other OEMs). I do know what apps are available for other EVs. 

I hope this helps.

JKenH

Typhoon2000 said:

So when MG or other manufacturers quote the range of cars per charge, are they quoting 0-100% or 20-80%?
Advice about not letting the battery drop below 50% often is also a bit worrying if they re suggesting that to maintain battery life you pr driving range between charges is 30% of battery capacity (80%-50%).

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

They are quoting 0-100%. I don’t know if that means from 100% down to the gauge showing 0% or down to when the vehicle actually stops. Most EVs have some extra useable capacity after the gauge hits 0. I can’t recall the exact figure but it’s something like 3kWh left in a 40kWh Leaf. Once you pass 0 though you have no indication  how much further you can go and you will be relying on remembering what the odometer said at 0 and past experience. In practice it’s not good to go below zero but at least in an emergency you know there is a bit more left.

If you’ve been on the Internet you  will have seen numerous articles comparing the quoted range and real world range. The real world range is actually achievable in most EVs in ideal conditions and with a light right foot. I once saw 176 miles from my 40kWh Leaf against a quoted range of 168miles. I could probably have driven another 10 miles before the car would have stopped. In adverse weather conditions and driving at motorway speeds you might only see two thirds or possibly less of the quoted range.

In practice though it is very rare that you can exploit 100% of the range. If you are starting with a fully charged battery and returning home you can use 100% as you know for certain that when you arrive home you can charge. Any other trips you need to be certain there will be a public charger available that’s working for you as you hit zero. If you have a Tesla and you are heading for a Tesla supercharger you can cut it that fine. The Tesla will even monitor your progress and divert you if it thinks you are not going to make it. Because of the unreliability  of the public EV charging network however most people plan to run their battery no lower than 20% before getting a charge. 

Once you are at the charger you can of course stay there until you have charged back to 100% but the fuller the battery gets the slower it charges. Don’t take this as gospel but typically it might take as long to charge from 80-100% as from 20-80%. In practice people move on once they’ve reached around 80% (unless you know that extra few per cent will get you to your destination without stopping again).  If you are on a long trip the most effective charging regime is to stop at 20% charged to 80% and rinse and repeat. That does mean that you’re effective range between charging stops is only 60% of your total range. 

If on the day you know your car will have a 100% range of 200 miles and you have a 300 mile round trip journey planned then you could stop at 160 miles (20%) and then charge up to 90% adding a further 140 miles to get you back home. 

If, however, you have a 350 mile trip planned then although your car is theoretically capable of making it with just one stop the reality is you will stop at 20% (160 miles into your trip) then charge up to 80% adding 120 miles and then when your car is down to 20% again (280 miles into your trip) you will do one more charge adding 35% to take you the last 70 miles letting you arrive with a margin of 20% battery left. 

photome

prowla said:

So, don't leave an EV uncharged for ~3 months.

The OP is arguing that is exactly what could happen to an EV on a garage forecourt. 

photome

JKenH said:

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.

JKenH said:

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.

There are lots around the eastern counties, prob not a day goes by that I don’t see one or two

Grumpy_chap

I have said before in this forum that I was concerned that the value of a used EV was really zero because there was no way to know how good the battery was and whether it had been abused by the previous owner.  I was roundly condemned at the time.

This thread makes me think that I may have been more correct than I thought.  Even if the abuse was not by the owner but by the trade Dealer.

So, I was looking yesterday online and the price of used TM3s seems to be dropping, and i am trying to understand how anyone would assess the risk on this battery thing:

So, this 2020 expensive model at 18k miles, untaxed since 2nd August and so likely to have a massive bill for a new battery:
https://www.autotrader.co.uk/car-details/202212232739639

This 2019 at £33k and 20k miles, untaxed since 23rd January, so expect a better battery:
https://www.autotrader.co.uk/car-details/202301303748535

This 2019 at £33k and 28k miles, untaxed since 2nd November, so expect a battery problem:
https://www.autotrader.co.uk/car-details/202212162563603

All of the above likely trumped by this 2019 at £29k and 37k miles, untaxed since 4th January:
https://www.autotrader.co.uk/car-details/202302033904584

Or, avoid the risk of a knackered battery and go for a brand new MG4.

Or, just get an ICE and use the savings in cost price to pay for some petrol:
https://www.autotrader.co.uk/car-details/202302023866738

JKenH

Grumpy_chap said:

I have said before in this forum that I was concerned that the value of a used EV was really zero because there was no way to know how good the battery was and whether it had been abused by the previous owner.  I was roundly condemned at the time.

This thread makes me think that I may have been more correct than I thought.  Even if the abuse was not by the owner but by the trade Dealer.

So, I was looking yesterday online and the price of used TM3s seems to be dropping, and i am trying to understand how anyone would assess the risk on this battery thing:

So, this 2020 expensive model at 18k miles, untaxed since 2nd August and so likely to have a massive bill for a new battery:
https://www.autotrader.co.uk/car-details/202212232739639

This 2019 at £33k and 20k miles, untaxed since 23rd January, so expect a better battery:
https://www.autotrader.co.uk/car-details/202301303748535

This 2019 at £33k and 28k miles, untaxed since 2nd November, so expect a battery problem:
https://www.autotrader.co.uk/car-details/202212162563603

All of the above likely trumped by this 2019 at £29k and 37k miles, untaxed since 4th January:
https://www.autotrader.co.uk/car-details/202302033904584

Or, avoid the risk of a knackered battery and go for a brand new MG4.

Or, just get an ICE and use the savings in cost price to pay for some petrol:
https://www.autotrader.co.uk/car-details/202302023866738

Digressing but I looked at the PCP quote for the first Tesla you listed  (2020/20) and the final payment after 4 years was £18,240. Tesla when financing a new M3LR adopt a final payment after 4 years of £18,866 - that’s for a car that’s 3 years newer. Somebody’s gonna get burned.