Ownership Verified: NooDle’s EV take 2 : The Mullet (Kia EV6)

A question to fellow EV drivers (or anyone else who may have knowledge on this) : what's the deal with only charging to 90% purposely?
I'm reading this everywhere that you should never charge to 100% unless you take a drive immediately after, but I thought this was mainly for older batteries.
I'm still seeing this more and more, and am unsure whether this is still a thing or not.
For the record, my car is a lease, so I don't really care about longevity (since I'll be getting rid of it within 3 years anyway)

Also, I don't always know when I'll be needing range, so I usually charge up to 100% anyways. Not daily, but let's say 3 times a week.

Am I slowly killing my battery or doesn't it really matter? I thought all batteries were purposely larger than their actual size (eg my EV6 has a 82kwh battery of which only 77 kwh can be used), so there's always a top buffer. So, even when I'm charging to 100%, I'm really at 95 or so.

Opinions? FWIW I'm not planning on changing my charging behavior (because I'm stubborn and lazy), but curious to see what other people think/do.
 
For the record, my car is a lease, so I don't really care about longevity (since I'll be getting rid of it within 3 years anyway)
In this case I'd say keep doing what you're doing, who cares...

I thought all batteries were purposely larger than their actual size (eg my EV6 has a 82kwh battery of which only 77 kwh can be used), so there's always a top buffer.
The top buffer size varies wildly, though. I think the whole recommendation stems from Tesla making the "90% daily limit" very clear in their cars and UI (for the NMC, does not apply for LFP batteries, those love 100%), because their top buffer is comparably small.

I basically have my limit at 80% and leave it there unless I'm going for a long drive or if I feel the car should go up to 100% for a change to help the BMS or something, I dunno. Basically twice a year.
 
@eizbaer hit the nail on the head there, I run 80% as a charge limit and I also tend to only charge once every 2-4 days depending on driving plans - Or when SOC drops below 60%.
 
Yeah it depends if 100% is really 100%. I've always charged to 90% unless I really need 100% or am immediately leaving when the charging process finishes.

I think there's also a difference whether you're fast charging or AC charging.
 
Sample size of one; first generation Volt with the 16kwh battery, after about ~150,000km and eight years it lost about 15% range, but then a few cells failed inside and required replacement. Each charge was to 100%, and I probably cycled it a few thousand times with full-charges, charge/discharge/mountain modes/etc. Much smaller pack with frequent charges; 25-100% several times/day. GM did have a significant safety buffer on it, only allowing it to discharge about 11-12kwh, so that likely prolonged the life by not allowing it to go completely discharged, along with very limited charge speeds at 3.3kW level 2.
 
hmm, unteresting.
I want to know what is causing the deterioration in the battery, is that keeping the car at 100% (as in, charge it to 100% and then letting it sit for a couple of days), or is it just the cycles / amount of times the car is being charged?
Because my car is never at 100% for more than a day, and I don't charge it every day, only when it gets below 50% or so (since sitting long at low charge is also bad, it seems).

What would be worse, charging it to 100% every day (even if it's at 95%) or letting it drop really low every time? Seems like you're damned if you do and you're damned if you don't?

DC charging does no damage I think, but it may reduce charge speed if the battery gets too hot. So there's a built in safety feature there.
I mainly (90% of times) charge on AC at home. Because convenient.

Also, I know this is irrelevant because "someone else's problem". I'll never reach 8 years ownership or super high mileage.... Just curious to hear your thoughts/experiences on this.
 
Everything you described causes deterioration. Except i think you have to adjust the way you think of a cycle. 0-100 once is one cycle… but 50-100 is half a cycle. It really is the multiplier of total capacity, not the amount of times you plug it in.
So: doing 50-100 is worse than doing 50-75 twice. similar for 50-0 vs 50-25 twice, but I’m not sure on this one. Also charging fast will be worse than charging the same amount slow (it’s not just the potential to overheat at some point, there usually really is degradation involved hence why excessively supercharged Tesla’s will have lowered charging speeds at some point (or at least used to)).
 
The conversation above is why I'm excitedly waiting on the miracle battery where you don't have to worry about any of this. :p
 
No, returning a lease within warranty period is the way to not worrying :p
 
I feel so old when I read this kind of discussion
 
The conversation above is why I'm excitedly waiting on the miracle battery where you don't have to worry about any of this. :p
It's all overthinking anyway because you don't give a hoot about the longlivity of your petrol engine in regards to your driving style. With EVs it will soon be the same. Batteries are proctecting themselfs by slower charging when above 80%, and that's about it.
 
The conversation above is why I'm excitedly waiting on the miracle battery where you don't have to worry about any of this. :p
No, returning a lease within warranty period is the way to not worrying :p
Yeah, for one, there is this.

And then, it could just be a question of cost... most OEMs take care of the 0/100% issue by just using a larger top and bottom buffer than tesla does - so as the owner/driver you don't have to give a crap anymore. At that point, it's only a question of cost, really, since you're paying for more battery than you're allowed to use in the end. Miracle battery in this case would mean a cheap battery. That's already happening for sure.
With the fast charging thing... I don't actually know tbh. Maybe certain batteries don't really care, at least not noticeably? LFP batteries have insane cycle stability as it is, so maybe even exclusively fast charging doesn't do anything noticeable to the battery in any case, because you won't ever reach a point in regular use where degradation would become noticeable.

So what I'm saying: no need to wait for miracle batteries, really :D
 
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I've put 40k km on mine and I've yet to see any degradation anywhere in my normal use. I'm only getting rid of it because I don't want to pay new car lease payments for something that approaches two years of age, especially since the center stack/infotainment warranty is only two years (rest of car five years, battery warranty eight years). Since the whole point of new EV motoring is being hassle free, I realize I have to rotate cars often enough not to get caught out by anything I would have to pay for myself except for scheduled maintenance (150 bucks every 15k km).

That said, I've seen some posts about 28kWh Ioniq electric motors failing and needing replacement. In actuality only the main bearing has let go, but the main dealer only does the entire electric motor, to the tune of 20k eur, if you're just out of warranty. Super sucks, but if you just got one for a decent price there are independent shops that can take care of the actual issue.
 
That said, I've seen some posts about 28kWh Ioniq electric motors failing and needing replacement. In actuality only the main bearing has let go, but the main dealer only does the entire electric motor, to the tune of 20k eur, if you're just out of warranty. Super sucks, but if you just got one for a decent price there are independent shops that can take care of the actual issue.

Car manufacturers have to realize they need to stop doing shit like this.
 
It's all overthinking anyway because you don't give a hoot about the longlivity of your petrol engine in regards to your driving style. With EVs it will soon be the same. Batteries are proctecting themselfs by slower charging when above 80%, and that's about it.
This. All of the old TG episodes where they dyno old cars to see how many HP they "lose" underlines this. Stuff just normally wears out with use. With an ICE engine there's not a lot you can do IMO : change the oil frequently enough and get stuff serviced, but aside from that it's a crapshoot.

But because EV, and 1 moving part, it's more down to how people use it.
Sure, I'm not worried (because 7 yr/200K kms warranty on car/drivetrain/battery), I'm just checking to see whether the 'don't fully charge it' thing is still a thing. I have a coworker who worries about this endlessly, despite having a similar lease car (VW ID4).

he NEVER charges above 90%, only charges on a slow charger unless absolutely needed, and generally drives like an old man (100 kph instead of 120 kph on the highway). He does get crazy mileage doing this though... (he claims 500 kms from 77 kwh)... I'm kinda tempted to try this too (the speed thing, not the 90% thing) but then again I am impatient in traffic and I'm not sure I can purposely drive so slowly just to prove a point.
On the other hand, I am quite petty about these things....
 
I've put 40k km on mine and I've yet to see any degradation anywhere in my normal use.
no idea about degradation tbh... now at ~90kkm. to notice actual battery degradation, I think you have to actively measure it - otherwise you won't notice. So one more for: who gives a hoot.

What I've been noticing more and more is that my actual consumption / efficiency is insanely all over the place. And not really explainably through temps or weather or elevation or stuff like that... it's a bit weird and tbh I do think about it too much.

But what the whole thing shows me (also the regular 80% thing) is that I'd be perfectly happy going leviathans route and driving a 60kWh LFP model 3 - it wouldn't change a thing or make it any more or less useful of a car to me. Even on long drives I'm more often than not actually hounded by the fast charging (i.e. I have to get going because the car's finished), rather than having to wait for the charge to finish. bring on the highland refresh, don't stuff it up and I might even think about replacing my early model for a new one :p
 
The best thing is to try and hypermile and optimize the cheapest charging, I get far more kicks out of it than anything else automotive related :D

(I'm 40 next year)
 
Reads above

....I think I straight up don't like cars anymore
 
The best thing is to try and hypermile and optimize the cheapest charging, I get far more kicks out of it than anything else automotive related :D

(I'm 40 next year)
I'm not THAT sad yet, I'm trying to get the best charging speed record (the few times I do fastcharge that is)
Also nailing it at the lights is still fun in an EV so it isn't all bad.
(I'm 41 with 2 kids, but still a child on the inside)
 
Yeah, with the 200hp Kona I'll definitely do some stoplight racing (but not so much that I'd have to buy my own tires)
 
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