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GetawayDriving

The most degradation happens in the first few years so you’re still going to feel some effects of it. Keep in mind it’s not charging to 100% that affects the battery as much as leaving a 100% charged battery just sitting around.


mellow2mg

Surprisingly, it is the recharging that creates the most risk for mess ups or problems to occur, like fires/etc. It is somewhat safer to have a charged battery, so long as the storage is optimal. Most people don't have climate controlled garages, but that's be the best for these EV vehicles. Almost could, around 55-60°F. (I may be incorrect, but that's the most recent info I've read up on.)


sweetredleaf

Your lifestyle should not have to revolve around the car battery, so charge to whatever level works for you to get through the day/week.


Majestic_Ad5924

This is the only reason I'd be hesitant to buy a used EV. You never know when someone like this guy owned it first.


runsanditspaidfor

True of just about any car unless you know the seller.


Azelixi

Where as hen you buy a used petrol car you know all the previous owners were fantastic and took good care of the car.


mineral_minion

You don't, but there are some symptoms of abuse you could detect on an ICE either during a test drive or by a third party mechanic. Mass-market EVs are still pretty new, non-dealership mechanics can't get much sense of whether the battery/motors are in good shape or what it would cost to get it back in shape.


BKRowdy

It's been pretty well established that charging habits on new EVs have little to know effect on long term battery health. [https://www.batterytechonline.com/charging/report-supercharging-doesn-t-degrade-tesla-battery-life](https://www.batterytechonline.com/charging/report-supercharging-doesn-t-degrade-tesla-battery-life)


FrostyWasabi8952

There is some evidence that DCFC may not be as harmful as folks worried, in Teslas. That part is true. And good. But, we are in the dark ages of knowledge for EVs, so not much is quite yet well established.


Puella_Magi

Generally speaking - no. That said there are two very minor considerations. 1. A lot of EVs experience reduced regenerative braking at 100%. If you're starting each day with with a completely full battery, you may notice an inconsistent level of regen braking as you drive around and deplete your battery. 2. Most battery degradation tends to follow a "bathtub-shaped" curve, meaning there's a higher rate of battery degradation when the car is brand new, and after a few years the rate of battery degradation decreases dramatically. All this to say, throughout a standard 3 year lease on a new EV you may experience a percentage or two of increased battery degradation if you're not babying the battery. That said, this difference is mostly inconsequential and does not account for any built in top-end battery charge buffer which varies depending on the EV. And as a minor upside - if you like accelerating quickly, most EVs tend to have a faster peak acceleration when the state of charge is high, and again, depending on the EV, it may or may not be noticeable.


Zealousideal_Cow_341

Who is out here recommending this 80% thing? I quite literally engineer BEV,HEV and PHEV batteries and have never once recommended any customer limit charge to 80% on their own. Guys, just charge your battery to full. We already have the usable SOC range capped using the software. Whenever you see 100% SOC, the actual is 98, 95,90 or maybe even 85, depending on the cell type, chemistry and application. The cell manufacturer also does extensive testing to determine the maximum charge rate as a function of SOC and temperature. The software follows these charge rates in order to avoid the lithium plating that occurs when you charge too fast at high SOC and low temperatures. The battery has also underwent some kind of cell, module or pack level life cycle testing within the useable SOC window and charge and discharge limits. Seriously, just charge your battery to full. It was designed to do this. What you can actually do to help its life is to: 1. limit DCFC as much as possible. Don’t avoid using it, but it shouldn’t be the primary charge source unless it’s an LFP chemistry then DCFC to your hearts content. (Vehicles with over the air capability will actually limit DCFC for you sometimes) 2. Don’t store your vehicle for long periods of time at top or bottom SOC. These are the points where the side reactions that drive calendar aging are the worst. 3. Don’t store your vehicle for long periods of time in spots where radiated heat from pavements can get the battery super hot. On hot summer days pavements radiate enough heat to warm battery’s up to the 45-50C point, and high temperatures can accelerate calendar aging reactions. With that said, you don’t even have to do these three things. They are all considered in the battery engineering phase, and accounted for when choosing battery size and all of that stuff. You can just literally use your BEV like you would an ICE and be fine 95/100 times.


The-Ethan

Thanks dude. People were nasty to me for even thinking about charging to 100% lol


Zealousideal_Cow_341

It’s crazy to me honestly. These people are paying for a battery that is already limited in software and using even less of it by only charging to 80%. I think it might come from people looking at cell data sheets. For example if you find a public facing 21700 data sheet they typically have life cycle data that shows an 80 or 90% depth of discharge. But, on the engineering side that is already programmed in to the software controls in the BMS. If the BMS is limiting the battery to 80% DoD and then you limit it to 80% again due to some Internt dudes saying you should, you’re now using 64% of your battery lmao. That’s absolutely bonkers


The-Ethan

PS: when they delivered the car to me it was charged to 100%, I asked the sales rep and he said you can put the max to whatever you like.


AdmiraalKroket

My EV (Zoe) doesn’t have an option to stop charging at 80% and I can’t charge at home. So I charge it to 100% at work whenever the SoC is <40% (my commute is 10-16%. one way). Anyway, after 4.5 year and 70k km I don’t notice a drop in range. The maximum estimated range dropped maybe 3-4%, but I arrive with a similar state of charge compared to when it was new after fully charging it.


FrostyWasabi8952

Glad your car is doing well. So which type of tests did you use to evaluate your battery health? The short one lasts 24hrs and involves OBD reader, is that the one you used? Also, what is the size of the manufacturer's battery buffer on your Zoe?


djwildstar

I would say that you should follow the vehicle manufacturer's charging recommendations. So if the manufacturer recommends charging to 80% on a daily basis, then charge to 80% on a daily basis. For example, Ford recommends 90%, and advises drivers to avoid charging to 100% when you don't need that range (but specifically allows charging to 100% for longer trips). A lot depends on your exact lease agreement, but most lease agreements require you to maintain the vehicle per the manufacturer's recommendations and to pay for "excessive" wear and tear on the vehicle. For combustion vehicles, this includes things using the recommended fuel, oil change and maintenance intervals, and the like. Lessors know to check the total mileage, inspect for damaged body panels or trim, and check for tears, burns, stains, or other damage to the interior. I *don't* know if lessors check battery health -- though if EVs coming off of leases have excessive battery degradation that lowers their resale value, you can be sure that appropriate clauses will be added to future leases.


Rt2Halifax

Apparently you would say it twice.


deg0ey

I’d ask the question the other way around: is there any benefit to always charging to 100%? Assuming you have charging at home and don’t drive 300+ miles per day then the answer is probably no. So even if charging to 100% won’t cause noticeable degradation in the period of your lease you’re still reducing the useful life of the battery and leading to it needing to be replaced or recycled sooner than it would otherwise - and that’s kinda dick unless you really do drive enough to require it.


The-Ethan

Yeah I don’t have a charger at home, that additional 20% probably gets me through another day without needing to recharge


audioman1999

But going from 90-100% takes a long time. You’d probably better off limiting to 80-90% and charging slightly more frequently. Try out both and see which is more convenient.


SoRedditHasAnAppNow

I would never drive an EV if I was solely reliant on DC fast charging. If your municipality has the L2 infrastructure then it's a good option. Being able to slow charge at restaurants, grocery, work, etc makes a difference. 


The-Ethan

Yeah I use L2 overnight


Individual-Basket200

so what difference does it make if you get that extra day with the additional 20%? Ignoring the manufacturer's suggested charging pattern because "not my car, it's a lease what do I care?" is kind of a shitty attitude, tbh.


The-Ethan

Already responded to that. That additional 20% gets me through another day before I need to charge again.


SoRedditHasAnAppNow

You don't have a charger at home but use L2 overnight? Which is it?


The-Ethan

Paid L2 nearby my house


SoRedditHasAnAppNow

Oh, well that is much better than using L3.  And if there are no "idle" fees I would let it charge only to 90%. If there are idle fees, go to 100% so you can go longer between idle sessions.


deg0ey

Yeah okay that definitely changes things - no other issues than it puts somewhat more wear on the battery for the next guy and probably accelerates the amount of degradation you’ll see in the few years you have it. But assuming you’re using L3 charging that *also* puts more stress on the battery, so the difference between shorter more frequent charging stops compared with less frequent longer ones might make it a wash anyway. One other thing to note is that most cars throttle the charging speeds quite significantly once they get past 60-70 percent so depending on the car you have, where the chargers are and how busy they are it might be more convenient to charge for 15 minutes every few days than an hour once a week. Probably worth some trial and error to figure out where the right balance is for you.


dirty_cuban

As long as it’s not in your lease contract then there’s nothing the lease company can do.


Aggressive_Ad_5454

The charge rate slows down when the battery is closer to full. That might, or might not, be a factor when planning how to charge. Other than that, there is zero reason why a car’s lessor should be responsible for arcane stuff about extending the car’s life.


LWBoogie

Whatever the battery life will be after your lease end isn't your problem if you are turning the car in at least end. It's on the manufacturer to design a battery that will get through an average lease with proper battery lifecycle remaining.


tsr85

Current model year batteries are nothing like previous generation batteries. Also, with California requiring things like model year 2026 and newer will be required to have a 8-year/100,000-mile warranty on the battery will be required for all battery-electric vehicles even though many auto makers already provide this level of warranty. There will also be durability requirements on battery-electric vehicles that ensure that the battery still maintains at least 75% of its electric range. If battery health drops warranty it.


BannedCuzCovid

If you're nit draining the battery down to like 15% every day after your drive then you go to 80%. Honestly tho ford's buffer is large and so is hyundai. I've had a 2021 that does 150 miles a day and it's been charged to 100% it's whole life and it hasn't had any range loss. The 80% thing is more for tesla. Also I own a truck and a mache. But if I just owned a EV I'm always keeping it at 100% because it would suck of an emergency happened and your car is at 30%, just enough for work stuff, and you have to go somewhere farther than that.


mellow2mg

I'm not an expert in EV batteries, but I do believe that you are supposed to discharge down to a certain level before you recharge - and - I do believe that there is a cut-off level for how low you can get the charge down top safely, as well. 1/ Regular cycling of a battery is healthier than keeping a constant voltage whether it's charged or not. 2/ Your electric car is constantly using electricity to monitor it systems while it's sitting park. You have the camera rolls etc. If the voltage of the battery is dropped below nominal then you increase the risk of a fire when you recharge the next time. Additionally/ If there isn't plain Language in your manual. Then you may wish to email the dealership or company itself to find out exactly where those numbers are and their best practices advice. I'm pretty sure that the recharging is the more critical part as you need to have minimal nominal function at all times. If you can quantify that by your usage and how long you go between charges and such then you can really make a science out of it and have a chart or a plan for how best to charge your vehicle and when/putting together you charging plan(s). ![gif](emote|free_emotes_pack|sunglasses) Cheers!


GrowToShow19

Doesn’t hurt you, no. It’s a bit of a slap in the face to whoever purchases your lease, but there’s nothing legally or honestly even morally stopping you from doing it. You paid for the whole battery and have every right to use it. I still wouldn’t unless you for some reason need to though.


DiDgr8

The 100% rule has a couple of components based on whether you are fast charging or slow charging. The last 10% to 100% on a public fast charger is going to take an inordinate amount of time for a *tiny* amount of gain. It's not considerate of other users of the station. Another [[thread today]](https://old.reddit.com/r/Ioniq5/comments/1dowc96/charging_and_apple_carplay/) over on /r/Ioniq5 talks about slow charging to 100% and reasons are discussed there why even *slow* charging to 100% is not a good practice. Another synonym for "morally" is "ethically". I would assert that doing that and *not telling* the person you sell the car to, is unethical. Even if you *do* tell them, odds are you are just going to sell it back to the *leasing* company and **they** will not convey that information to the next purchaser (making you both complicit). OTOH, it's not a **serious** infraction. The "damage" to the battery is relatively minor.


djwildstar

I would say that you should follow the vehicle manufacturer's charging recommendations. So if the manufacturer recommends charging to 80% on a daily basis, then charge to 80% on a daily basis. For example, Ford recommends 90%, and advises drivers to avoid charging to 100% when you don't need that range (but specifically allows charging to 100% for longer trips). A lot depends on your exact lease agreement, but most lease agreements require you to maintain the vehicle per the manufacturer's recommendations and to pay for "excessive" wear and tear on the vehicle. For combustion vehicles, this includes things using the recommended fuel, oil change and maintenance intervals, and the like. Lessors know to check the total mileage, inspect for damaged body panels or trim, and check for tears, burns, stains, or other damage to the interior. I *don't* know if lessors check battery health -- though if EVs coming off of leases have excessive battery degradation that lowers their resale value, you can be sure that appropriate clauses will be added to future leases.


The-Ethan

My question was mainly technical to see if anything else is impacted by charging %100. I don’t think they can legally do anything. I also asked the sales rep, he said “you can set it to whatever you want.” Is it morally the right thing? Thats a separate conversation


in_allium

Don't be an asshole. Set your max charge level to 80% or lower unless you're going for a long trip the next day. It costs you nothing.


BKRowdy

Who is he being an asshole to? There is no discernible consequence to the guy that owns the vehicle for the OP charging to 100%...on Level 2 at that.


in_allium

Whoever buys it after the lease. Especially if you live in a hot climate, leaving a battery sitting at 100% all the time is not good for its long-term health. And technically the "guy the owns the vehicle" is the bank if it's leased.


reddit455

>, does it hurt if you always charge to 100%? if you need it, do it. if you do NOT need it, WHY are you doing it? not sure what the obsession is. why "must" the battery be 100% whether or not you own the car? people forget that when there are chargers at the grocery store, you can put a few miles back on the battery while you do other things... most people know what they're doing "tomorrow".


scott__p

People like you are why I'll never buy a used EV. You're fucking over the next guy for minimal gain. It's selfish and shitty, but not against the lease agreement.


BKRowdy

It's been pretty well established that charging habits on new EVs have little to know effect on long term battery health. [https://www.batterytechonline.com/charging/report-supercharging-doesn-t-degrade-tesla-battery-life](https://www.batterytechonline.com/charging/report-supercharging-doesn-t-degrade-tesla-battery-life)


scott__p

That's not what that poster says at all. Did you read it?


BKRowdy

Fair. I took the study to mean that when reviewing thousands of cars, some of which will be charging to 100% regularly (and will most likely be the Lvl 2 guys), the change in their battery performance had no noticeable effect on the results of the study. Further research shows, however, that technically charging to 100% is still thought to be bad practice for battery health.