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by belltaco 896 days ago
Where does this myth come from? Looks it's about 10% battery degradation after 200K miles. Tesla is rating their batteries for 300K to 500K miles.

Most American company ICE cars are scrapped by then. Not to mention all the ICE related maintenance costs over that time like oil changes, transmission fluid, timing belts, hoses, etc. etc.

You can look at 6 to 10 year Model S cars.
2 comments
rootusrootus 896 days ago
> Where does this myth come from?

Politics.

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throwaway15858 896 days ago
The problem is the degradation is fastest when it's brand new.
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rootusrootus 896 days ago
Sure, but when the overall degradation is pretty minimal, this doesn't matter terribly much. I'm at 96.5% rated capacity after 12K miles. That's pretty typical. I should be down near 90-93% capacity at 100K miles. I probably won't keep this car long enough to get down to 80%. At that point I -might- consider replacing the battery, but given how old the car will be, it's not too likely. The only way the battery ever gets replaced in this car is if it fails altogether.

Right now if I had to pay that out of pocket it would be more than a new engine, but not by a huge amount. By the time I don't have a battery warranty, the cost will most likely be in line with a used engine for a similar ICE car.

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Dylan16807 895 days ago
Problem how? That sounds like the opposite of a problem to me. Everyone is used to a car massively dropping in value immediately after purchase. If the battery drops right away and then that slows down a lot, you won't need a replacement for a very long time.
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samketchup 896 days ago
It's not a myth at all, and Tesla's "rating" is a lie. Look at data on Prius battery packs and what Toyota rates them for(100-150k). I understand I'm comparing a hybrid to an EV, but there is much more data and I actually trust Toyota.

Buying an EV with 100k miles and the original battery pack for 20k is a bad idea.

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gridspy 896 days ago
Lithium-ion battery lifetimes are based on charge-discharge cycles.

The Prius battery is far smaller (about 5-10x smaller) than a Tesla battery, so it is cycling charge / discharge far more often.

So you'd expect the same quality battery to last 5-10x less miles in a Prius than a Tesla driving the same distance. It's likely that Tesla's investment in battery quality and active temperature controls mean the Tesla battery is also treated better and higher quality.

Topping that battery up with a generator in the Prius complicates things, both reducing kWh used per mile (some from generator) but also allowing a discharge - recharge cycle to occur multiple times in the same trip.

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cyberax 896 days ago
There are multiple sites that track real-life Tesla battery degradation. It averages at 12% after 200k miles: https://insideevs.com/news/664106/tesla-battery-capacity-deg...

I have a Tesla, and I use it in the worst possible way for the battery: road trips with deep discharges and frequent 100% fast charges. I'm at 100k miles, and it degraded by 9%.

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rootusrootus 896 days ago
> I understand I'm comparing a hybrid to an EV

I don't think you do. Prius's have only recently started using lithium ion batteries, for one. And they cycle the small battery a lot faster than a BEV. Everything we've learned from hybrids suggests BEVs will get hundreds of thousands of miles from the battery (and so far, from the cars which haven driven that far, this has proven correct).

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