Silly question about electric car

[billandtedsexcellentadventure]

Looking to buy a used one. Does the mileage make a difference? Should you always go with one with lower mileage??

Mileage does make a difference in terms of how much charge the battery can hold
in my experience. Like an iPhone that is older and the charge doesn’t last as long. E.g. mine is. 2022 model and on paper it should do 180 miles on a full charge but the true range is closer to 100.

Thank you. That’s explained it. Just didn’t know whether I needed to take it into account.

Makes a huge difference on an EV. As pp said rechargeable batteries hold less and less charge over time. If there is an older cheaper EV catching your eye and you are wondering why the price is low, this is why. Avoid.

The battery % is important. How many miles the battery has when it’s fully charged and how many it would have had when it’s new.

I mean there are many other factors which impact range (real vs the LIES the dashboard tells you) including temperature, how much you are pounding the heat/AC, driving style, urban vs motorway driving etc but battery age is a critical factor. I would say to be super wary of very cheap second hand EVs. Maybe try one on lease first to see how you get on? If you do a lot of long distances it’s a lot of admin.

You can ask to see the battery health report. I recently bought and EV at 18 months old and 9k miles. The battery health was still 100%. If the battery is looked after in terms of never letting it get too low, charging to 80% most of the time and avoiding lots of fast charging then the battery will last really well. The warranty cover usually lasts 8 years and they will replace if it is at less than 70% within that time.

Yes, offset the cheapness against cost of new battery (I think £10k is what I've heard but check as I'm definitely not an expert!)

But doesn't mean it will necessarily be a bad deal as I think other parts wear out less quickly. If cost of car is still a good price even if you had to replace the battery in a year or two it might still be worth buying. Also if it's high mileage but relatively new then some cars come with a 10 year battery warranty so might be worth checking if that's transferrable to new owner.

There are high mileage EVs out there that still have good battery health, my understanding is that it depends on the make and model and how it was charged. Early Nissan Leafs had small batteries and many have degraded badly especially if often rapid charged. I understand there are some Teslas, MGs and probably other makes too, that have high mileage but still have a lot of range ahead of them. I would be looking for a car that has a full manufacturer service history and some battery warranty left - the warranties often have terms and conditions about the number of miles in a year, the service intervals, exclusions for particular uses - eg using the car for taxi work will usually invalidate the warranty. I would want a state of health report (SOH) from a main dealer (I get this on my annual service report). Don't rely on the dash as there are ways of resetting the range counter to show the theoretical maximum. Clearly there is a big difference between buying a car that is 1-3 years old versus buying one that is 5+ years old, as there would be with buying a combustion engine car.

@billandtedsexcellentadventure

A secondhand EV has the same fundamental issue as a petrol or diesel one - you don’t really know how well it’s been treated, so in general a lower mileage vehicle is better, but that’s not to say a higher mileage one is trashed.

It’s a myth that EVs need their batteries replaced (except perhaps for the really early ones). Most built after 2018 have excellent thermal management of the battery (the things that phones do not have, so anyone comparing an EV battery to a phone doesn’t know what they’re talking about).

The thermal management is very important because Li-ion batteries like to be kept at temperatures humans like. Rapid charging, particularly beyond 80%, heats them up, as does heavy-right foot driving, so modern EVs actively cool the battery. If the car is very cold, the battery is actively heated as you drive (or preheated beforehand), and to manage a rapid charge as quickly as possible, preheating can be done then too.

As a result, battery warranties on new cars are now typically 8-10 years or 100-150,000 miles, and they’re only provided because the car companies know only very few claims will be made at that point.

But batteries, like engines, do slowly wear out with use and age, so the posters that advise getting a battery condition report are correct, and it’s well worth arranging for a multi-day test drive so you can check for yourself if all seems well.

We know many people who have bought secondhand EVs and they are all delighted with them. DS has a 2018 BMW i.3 which is nudging up towards 100,000 miles (he does a 50 mile commute each day), and he recently did a test on his. He thinks it has lost almost nothing of its original range.

Two things to note though, firstly the “on paper” range (also known as the WLTP one), isn’t a very good guide to what you’ll get from an EV. It’s not hard to drive way harder than in test conditions and return 50% of the “on paper” range (just as the stated maximum mpg for a petrol car was only ever a “best case if you cruise at a constant 56mph”) so the poster claiming that was evidence of rapid battery degradation is most likely not taking that into account.

The second thing is to look for an EV with a heat pump. The thermal management of the battery is then integrated with the motor & cabin heating and cooling and all is done a lot more efficiently than with resistance heating. Our Polestar 2 has one, but lots of older EVs don’t have. Without a heat pump you might see a 20-40% range reduction on a very cold day, whereas we see maybe 5%

@Ayebrow thank you. That’s really informative. How do I check the battery health?

Main dealers are able to provide battery health reports, if you are buying from one of them. When we bought a 4 year old Nissan Leaf (back in 2018, so it wasn’t one with the best battery thermal management in) it was through a Nissan dealer and came with a battery health report.

DS’s BMW i.3 has pretty comprehensive information from the onboard computer but a dealer can get the full readout. DS is very geeky though and has an OBD connector with an app that can tell him even more detail.

This is a really useful site to help you:

Checking battery health

Buying privately would probably carry many of the same risks as buying an ICEV that way, but you may be able to insist on getting a dealer battery condition report from the seller or walk away.

If that isn’t an option, then as a minimum I would want to find out as much as I could about the checks I could do myself for the model of car I was buying (see that link), or visit some user forums and see what kind of range the car should have for a given battery %, and what kind of miles/kWh you might expect. Also what size battery it has in kWh.

Ideally ask for a test drive with the car showing at least 80% charge and do at least 20 miles driving in it so the battery is warmed up, and you should be able to get a good idea of whether the consumption is in line with expectation. Most EVs will report the miles/kWh that you’re achieving (or in our Polestar’s case kWh/100 miles), and after 20 miles the anticipated range should be pretty accurate. It won’t be anything like the WLTP range advertised when new, unless you’re driving at a steady 28mph at 25°C or something, but it should be in line with the “real world” figure you can find in the EV database.

EV real-world range

If the car has, say, a 50kWh battery, and has used 10% battery in 20 miles, then it’s managed 4 miles/kWh, and it’s range will therefore be 200 miles.

As long as you don’t go too heavy with your right foot, or brake too hard (so that regen gets a chance to do most of the work in slowing down, rather than the friction brakes), and the test drive is on a day warmer than 10°C, the car should be able to hit the “real-world” figure.

Op go for one that is no more than a year old and still under warranty from its manufacturer. I wouldn’t touch one that has done more than 10k. EVs are super expensive to repair especially if the battery is worn out and it’s not worth the headache at all.

Either go new or secondhand but practically new.

@Helpboat

Either go new or secondhand but practically new.

That may sound like good advice, but if the OP’s budget can’t stretch to “nearly new” it doesn’t really help. All the people we know with EVs bought them secondhand and significantly older than “nearly new”, and all have been delighted.

Your post just isn’t a reflection of how EVs actually work. Modern ones (post 2018), have excellent thermal management, and manufacturer warranties upwards of 8 years or X1,000 miles on the battery, where X is a very big number. All evidence points to EV batteries outlasting the car.

People need to realise that where a petrol or Diesel engine can be thrashed to death, and abused from day 1 in many ways, it’s very hard to abuse an EV’s motor and battery, since the whole drivetrain is managed by systems designed to protect the car.

So I can get into a petrol car at sub-zero temperatures and before the engine has warmed up I can take it to 6,000rpm, doing untold damage to the engine. Lots of short journeys with a cold engine are death to an ICEV.

But a cold battery can neither be charged nor discharged quickly, so the first thing that happens in an EV is that the battery is heated before the thermal management allows more current to be passed in and out of the battery. If it’s too hot the battery is likewise actively cooled.

If the battery is very full or very empty, charging and discharging speeds drop to a trickle, so an EV cannot regen as much at high battery %, nor deliver much power at low battery %, and at whatever level of charge, the battery management system (BMS) limits how much power or regen is allowed.

We have driven hired Polestar 2s and Tesla Model 3s with 50,000+ miles on them, and their ranges were easily within the real-world range I have referenced in my post above.

With all that experience, I would have no hesitation in recommending an older EV with a long range as long as it has a heat pump and a decent remaining manufacturer warranty, rather than a new or nearly new one for the same budget with a lower range and without a heat pump and warranty.

What mileage do you need though? Will you have a home charger?

If you usually drive short distances most days with the occasional long journey and you can have a home charger then you don’t need a car with massive range. You can charge up overnight at home for peanuts, and for the odd long trip you can charge at a public charging station (which are more expensive).

I drive 12k miles a year but the vast majority of that is multiple short local trips. My cars range is 160miles if it’s cold and dark and wet, but that’s plenty. Almost all my charging is at home. There is so much public charging now I’ve never had a problem on my long drives.

I do about 8000 miles a year. Short journeys mainly. Can’t afford a brand new one. Maybe one about four years old? At a push. So a lot have done about 30,000 miles on average. Which is what I’m looking at. Range about 209 miles. Will get a home
charger.