Very unlikely it will need replacement I think. Mfrs reckon on capacity < 70% of original as being the threshold they'll replace it at. I believe it's 5 years unlimited miles, so unless you've done say 500k miles it should still be fine.

In USA there's a 2012 Volt Mk1 that done 450k miles and the battery in that's at 20% degradation, admittedly it's only been using the capacity range from 20% to 85% SOC, but it was 2012 tech and there's been a lot of development & more understanding of the chemical decay mechanisms since then, so 500kmiles should be manageable surely. Elon's been talking about 1 million mile batteries...

And if it's that degraded, it may be cheaper to get a new EV than to try to refurb it. There will still be a market for local-range-only EVs as 2nd cars, learners for the kids, ...

 

There's a good chance that current battery technology will be obsolete by then, so that's probably inpossible to speculate. EV's seem to be progressing like TV's and computers, they get bigger, more powerful etc and the price drops.
When will the demand for ever increasing range peak? Do onboard betteries really need that much range? Will en-route charging ever be so prolific that you can do any journey (a) without range/charger anxiety, and (b) a long wait for a free stall.
Another question might be: When will the £8k+ premium for buying an electric over a diesel/petrol vehicle disappear?

 

In the same way that it's very unlikely that your ICE engine will self-destruct when the warranty expires, the battery pack in an EV should have a long life after its warranty is up. It's also a matter of reduced capacity in most cases, not of an outright failure. How much capacity is enough? Even at half capacity the pack would have value, though possibly not to the original owner.

It will have value to someone. At the very least, it can be run through a quick diagnostic. possibly undergo a light refresh, and be put into service as stationary grid power. I just read about one utility that is doing that with tired Leaf packs.

By the time this becomes a genuine and not hypothetical concern, there will likely be plenty of companies that will remove your pack, test, inspect, replace any marginal cells, clean all connections and re-install it. (There are already a few.) Any useless cells go to the recycler. (Several facilities are already up and running.) Since decreased capacity is most frequently limited by one or a few weak cells (sometimes even a bum connection), your capacity will rebound and you'll have many years of use ahead. Just like an ICE car, when the engine finally wears out, no one buys a new engine from the factory. They get theirs rebuilt or exchange it for a rebuilt. It should be the same with battery packs.

 

This article suggests that a (remanufactured) 75kwh pack for a Tesla Model 3 comes in at around 14k USD and I believe the general consensus is that Tesla have the cheapest batteries in the industry.

The price will likely be a lot different in 5-10 years time though but certainly £8-10k wouldn't be out of the question, in my opinion.

 

I think that market forces will prevale.. if the price of an original replacement battery will be very high, it will open a gap in the market for smaller firms to refurb old batteries.

 

The chances of needing to replace the battery of any EV after 8 years is very slim. There are Nissan Leafs & Renault Zoe’s that have been around for 10-12 years, many miles and still 90%+ battery capacity. There will be battery exchange offers and replacement services as EV demand increases. I don’t see it as an issue.

 

Replacement cost of Kona EV 64kWh battery is currently about $15,000. That includes transport from Korea. I don’t know the differences between EV batteries in Kona vs I5 but wouldn’t expect much difference, maybe $18,000?

There are a lot of variables governing cost in 8 years. Of course in all likelihood the tech that will power zero emission vehicles in 8 years is yet to be been invented. But on current trends I would expect

1. efficiencies in tech will at least halve the replacement cost
2. battery reconditioning companies will develop ways of extending battery life and/or providing reconditioned exchange batteries
3. second hand batteries will be sold for second life as domestic/industrial storage systems.

 

Several mentions here about the tech changing. True, but the old tech isn't necessarily going anywhere. 18650 cells have been around for decades, and they're still available in a dizzying array of flavors. Where there is demand, there will be supply. I have even considered rolling my own replacement pack for my i-MiEV using 18650s, which would result in an increase in capacity.

 

In 8 year you would probably be able to replace it with a solid state battery with twoce the capacity for half the cost of current batteries…

 

Personal opinion is like you and others here said about technology of battery, it's the same pattern as computer, cell phone, etc as customer want.
This about retaining charge after 8 years, in my opinion this depend on how the car got rided. I mean, this I5 can do fast charging ( than more fast degradation as stated in the manual). Than, degradation can vary one car from others. For sure, I will not recommend used Ioniq 5 car on location because of this, people will not car with fast charging on location.

This said, personally, I do use those old battery (Li-Ion) to make new battery and there is not only the battery that take damage, bms too. And only this bms when it fail can fail an entire battery pack since not all BMS are equal quality.

For the forum members who can read the future

But en resumé, in 8 years, we will use completely new technology like those probably solid state battery they will got mature and maybe reliable at this time. And maybe specializes garage will do upgrade for those new battery for better one. On those old car like giving maybe 1000 km range to Ioniq 5.

 

I mean you get a car with the hope that you'll have it forever and in 8 years I'd expect there to be way more reliable chargers so a new car with better range isn't exactly required. My thinking on the batteries being cheaper would be in regards to the e-gmp, if all cars have the same frame then i would suspect that the batteries are built much more efficiently. (Tesla being the exception because of right to repair).

But i was curious about this as well. Would that help bring the cost down you think?

 

I was talking to a buddy with a model 3 performance that can barely make it past 160 miles at 75 on the freeway about this, the whole battery life and intended replacement cycle.

My understanding is that Tesla has such great numbers new because they use the entire pack and run the batteries harder while most conventional automakers would not like to repeat the GM LG fiasco of replacing packs mid warranty where at Tesla honestly expects to during that time.

If we use Out of Spec's experience seeing the battery degrade from an advertised range in the 300's to mid 250's over 100k the real question is, even with some degradation (say 10-20% over 8 years or whatever) will you really need to replace it or will say around 230 miles range best case be fine for your use at that time? A lot of focus is placed on the natural cycle of batteries but I rarely hear people projecting what they expect their commute needs to be in 8 years. If it's the American average of 33 miles a day and the pack is still good for over 200 miles and lets say charges a little slower but still under 30 minutes to that 80% capacity of the new total pack capacity - would you really spend 10-20k to replace it or just continue to use it as a city vehicle and not worry about it.

My first EV was an eGolf and could never reach 100 miles on a charge, with that vehicle estimated battery degradation would impact my then daily average compute of 60 miles. With the IONIQ5 I doubt I'd pay out of warranty to replace the battery if I still have it in 8-10 years.