Charging to 100%, why not?

[simcity]

True. Same rule below 20%. If you charge immediately no problem.
Just do not let to sit it long below 20% and above 80-85%.

Indeed. Very high and very low states of charge - for long periods - is ultimately what causes stress and degradation. Short term (hours or a day or so) it ultimately doesn’t matter.

….temperature is the other killer / factor, but that’s why our cars have state of art pack cooling and heating to maintain ‘Goldilocks’ temps during ultra rapid charging.

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[whitex]

For example, if you have ever charged a Tesla to 100% then you'll find you accidentally almost run into people expecting the 1-pedal regeneration to work "as normal" - but it doesn't. Why? Because at 100% SOC there is no where for the battery to recharge, so it disables this feature.

Just fyi, Teslas have had a feature implemented a while back which used the physical brakes to simulate regen when the battery cannot accept the full regen. This makes the driving experience consistent, when you let off the accelerator, the car slow down the same whether the battery is empty and warm or full and/or cold or too hot.

 

[whitex]

However if there was a battery failure during your ownership, and you were charging past the recommended SOC, it could stand to reason that this would show up in logs, and they could void the warranty. Somehow doubt any large auto maker would do this (that is more of a Tesla kind of flex). But still, it's like using the wrong octane fuel, etc.

Can you point us to where you got this information? Nowhere in the warranty text did I ever see any limitations to charging speeds or max SoC. I honestly do not believe voiding the warranty would stand against even arbitration, or a legal challenge in court.

 

[Jonathan S.]

The first time you charge to 95-100% at an EA charger (or any DC fast charger) you will have learned the answer to your question.

I’ve charged to 98% or 99% a few times at EA. Doesn’t slow down all that much. Since EA was so slow to begin with, rarely getting even close to the triple digits!
And it’s all free. At 29 minutes, unplug, then plug back in!

 

[whitex]

Sorry guys, maybe has been discussed previously but close to getting a GTS. Simple question to more experience owners, why not charge to 85% and not to 100% every time? Hear me out, on other cars (or electronic devices per se) like Tesla you dont want charge to 100% every time to preserve the battery, HOWEVER, Tesla allows you to use 100% of the battery capacity. On the Taycan only roughly 90% is available to the driver (dont have the exact numbers), remaining 10% are a buffer locked by Porsche.

That begs the question, even if you charge to 100% you never actually charge the battery capacity technically to 100% but only 90%. So why the caution?

If anyone is wondering why ask this question… live close to an EA charger and would charge the car for free…makes more sense to charge to 100% to have less trips to the charger.

It will be a leased car…long term viability not a concern

Given the above, your drawbacks of charging to 100% daily at DCFC stations are:

• time to charge above 80% is significantly longer. Try it, 95-100 will take you as long as 40-60.
• Storing the car at 100% will degrade the battery faster. I know it's a lease, but you might care about it if a year in your max range is reduced. Warranty only kicks in after 30% loss of capacity IIRC, so unlikely you will get it fixed.
• at 100% SoC, you will be using your physical brakes more. This may or may not require you to replace your brake pads before you lease is over. Depends on brakes you have and how you drive it. There may also be a lease provision about reasonable wear on the brakes, but I doubt they'd enforce it.

So bottom line, if you are fine with the above, given your situation, go for it. It might not be a popular opinion on this forum as post people try to preserve their Taycans (see how many people PPF them), nor the leasing company that has to sell your car at the end of the lease, or the next owner, but Porsche actually might silently want you to do this - I am sure they could use degradation data from someone who charges to 100% daily.

PS> Just FYI, Tesla recommends 90% for daily charging of their older batteries, but 100% for their latest LFP. Taycan recommends 85%. The unavailable portion of the battery you speak of is at the bottom end, not the top end - it's what's called an "anti-brick" buffer, to prevent the battery from reaching actual 0% even when stored for a long time. Lithioum ion batteries are not recoverable after they reach true 0% charge.

 

[whitex]

I’ve charged to 98% or 99% a few times at EA. Doesn’t slow down all that much. Since EA was so slow to begin with, rarely getting even close to the triple digits!

I've hit 253KW at EA, so yes, the 99-100% is comparably painfully slow. So slow in fact that I never actually had the patience to wait for 100% at EA (I have at home or a hotel before a trip day though, but that's overnight charging I don't waste my time watching).

This said however, even if the rest of the charging is slow due to broken EA chargers, the percentage time increase to 100% may not be great, but it's still time which adds up if you had to do it every day (time 90-100 at EA and multiply it by 365 days a year).

And it’s all free. At 29 minutes, unplug, then plug back in!

Probably still true, then again, even sessions which I forgot to unplug at 29 minutes and showed some charged dollar amount never showed up on my account. It hasn't been a year since I had my car, so perhaps some financial audit will discover it and they will bill me for the $5 or less that I owe them from my trip last winter, but I seriously doubt it. Most of my EA sessions (most would be free anyways) don't even show up at all in my app for some reason (but since some charging sessions do show up, there obviously is some connection in EA databases between my car charging and my account).

 

[arijaycomet]

Can you point us to where you got this information? Nowhere in the warranty text did I ever see any limitations to charging speeds or max SoC. I honestly do not believe voiding the warranty would stand against even arbitration, or a legal challenge in court.

Though I cannot speak to "charging speeds" I can tell you that the owner's manual clearly states maximum state of charge for longevity. If you want to test that out, by all means, by my guest. I'm not willing to f'k up a $150k car personally just to see if I degrades beyond my comfort level, and then hope/pray that I can win in court. Personally, I cant think of better things to do with my time, money, resources.

Again there is plenty "open to interpretation" stuff here. But the manual does clearly state that 85% will give you greater longevity. But it doesn't define "long trips" either (see: interpretation). I've got no other useful data to add here so I'll end with this excerpt from the owners manual for your quick & easy access:

General charging and care instructions
The high-voltage battery is subjected to a physical and chemical aging and wear process. This reduces the capacity of the high-voltage battery over its life cycle depending on the pattern of use and the environmental conditions, reducing the maximum possible range and increasing charging times as the battery ages.
The following measures can be taken to reduce high-voltage battery ageing and wear:

• When charging, make sure that the ambient temperature for the vehicle is between approx. 68 °F ( –20 °C) and +86 °F (+30 °C).
• If possible, do not expose the vehicle to sustained temperatures of more than +86°F (30° C), such as when parking in direct sunlight for longer periods of time.
• At ambient temperatures in excess of 86 °F (30 °C), connect the vehicle to the power grid after use and charge the high-voltage battery with alternating current (AC) to a maximum charge state of 85 %. Use the timer function.
• At ambient temperatures in excess of 95 °F (35 °C), avoid using "Range" drive mode immediately after charging with direct current (DC) over 150 kW in order to maximize cooling of the high-voltage battery.
• Preconditioning the high-voltage battery shortens the charging time. Particularly on long trips, initiate the charging process for the high-voltage battery using the Charging Planner and use the timer or profile function to charge with alternating current (AC) if possible.
• Use the timer or profile function to set the high-voltage battery to charge to a maximum battery charge level of 80 % for daily use of the vehicle, excluding long-distance trips.
• When the charge level is below 5 %, connect the vehicle to the power grid after use and charge the high-voltage battery.
• If required, a battery charge state of 100 % can be programmed before starting long trips.

Notes on leaving the vehicle unused for long periods
For idle periods of two weeks or longer:

• Do not leave the vehicle with a discharged high-voltage battery, but connect it permanently to the mains supply for trickle charging.
• Make sure that the charge level of the high-voltage battery is between 20 % and 50 % while the vehicle is left standing. The profile function can be used for this purpose, for example.
• Make sure that the vehicle is not permanently exposed to direct sunlight. We recommend that you park the vehicle in a roofed garage.

If a permanent connection between the vehicle and the power grid is not possible:

• Half-charge the high-voltage battery prior to leaving the vehicle standing (charge level 50 %).
• Check the battery every three months and recharge if necessary to ensure that the charge level never falls below 20 %.
• Make sure that the ambient temperature for the vehicle is between approx. 32 °F (0 °C) and 68 °F (20 °C).
• Avoid using the app. Establishing the connection between the app and the vehicle activates the high-voltage system, thereby discharging the high-voltage and 12-volt battery

 

[whitex]

Though I cannot speak to "charging speeds" I can tell you that the owner's manual clearly states maximum state of charge for longevity. If you want to test that out, by all means, by my guest. I'm not willing to f'k up a $150k car personally just to see if I degrades beyond my comfort level, and then hope/pray that I can win in court. Personally, I cant think of better things to do with my time, money, resources.

Again there is plenty "open to interpretation" stuff here. But the manual does clearly state that 85% will give you greater longevity. But it doesn't define "long trips" either (see: interpretation). I've got no other useful data to add here so I'll end with this excerpt from the owners manual for your quick & easy access:

Nothing in the warranty says there is a maximum number of "long trips", whatever the interpretation. Only maximum time or mileage. Lease terms (which are different than warranty terms) usually include "reasonable wear" clauses, but those apply to consumables which you just have to replace before returning the car or you must pay for it. If the battery degrades less than 30%, Porsche says it's not covered under warranty, so it's not unreasonable wear. If it degrades more, Porsche will cover it. Unless the lease states maximum degradation of battery, there is nothing they can do. Sure, you can be afraid they will charge you for paint swirls caused by you not hand washing the car during the lease, or for a stone chip on the font bumper you picked up at some point, but that's being overly paranoid.

 

[arijaycomet]

Nothing in the warranty says there is a maximum number of "long trips", whatever the interpretation. Only maximum time or mileage. Lease terms (which are different than warranty terms) usually include "reasonable wear" clauses, but those apply to consumables which you just have to replace before returning the car or you must pay for it. If the battery degrades less than 30%, Porsche says it's not covered under warranty, so it's not unreasonable wear. If it degrades more, Porsche will cover it. Unless the lease states maximum degradation of battery, there is nothing they can do. Sure, you can be afraid they will charge you for paint swirls caused by you not hand washing the car during the lease, or for a stone chip on the font bumper you picked up at some point, but that's being overly paranoid.

Understood. But my car is not a lease, it is a loan (2nd owner). So for me, the net cost of a new battery is quite a lot. Also you're talking about something else -- "normal degradation" has been clearly recorded as worse with DC fast charging than AC charging across various EVs across various institutions. You can spend your time googling that if you'd like; as I've been fully electric in my garage for 12 years, I've already read the articles but dont have the links handy. So going back to the OPs post to keep this on topic: yes, you can definitely DC fast charge all the time but it creates unnecessary wear/tear as well as a poor use of time for most cases (obviously outliers exist).

I knew someone with a 150k mile old Tesla Model S (2015 85D) that in 125k miles had spent 98% of its charging only at Superchargers. By 150k miles, the range was 20% below the original. That would technically be within the realm of acceptable by most standards right now; heck that might even be better than most folks expect. But that doesn't mean the consumer will be happy with that. I'd assume most folks aren't worried about Porsche (or Tesla) covering a battery with normal degradation; no, most folks are more worried about the loss of range, and how that might negatively impact their enjoyment and use of the vehicle.

So yeah.... if the OP wants to fast charge all the time, my goal in my replies was to let them know of the ramifications to the battery. As for the warranty aspect, if the battery FULLY FAILED (or in your example, exceeded the "normal degradation") but it was nothing but DC fast charged, with many short trips, I personally think Porsche has plenty of leg to stand on to refuse to replace the battery in those cases, based on -my- interpretation of the owners manual.

 

[whitex]

Understood. But my car is not a lease, it is a loan (2nd owner). So for me, the net cost of a new battery is quite a lot.

Ah, this is a key distinction. The OP stated he is leasing and intending to return, hence best charging strategy advice might be different.

PS> Full disclosure, I own my Taycan and plan to keep it for a while, and only AC charge it to 85% daily, as I also would prefer preserving my battery. I AC charge to 100% overnight before going on longer trips, and charge to what is needed (plus some buffer) during travel. When at a hotel, I often AC charge to 100% nightly as I know I will likely need the charge the next day or the day after if for some reason the hotel charger is blocked or in use by other vehicles. I used the same strategy over 4 Teslas in the last decade (2 Model S at a time), and their battery degradation was minimal (oldest was 8 years old when I sold it with minimal degradation).

 

[whitex]

As for the warranty aspect, if the battery FULLY FAILED (or in your example, exceeded the "normal degradation") but it was nothing but DC fast charged, with many short trips, I personally think Porsche has plenty of leg to stand on to refuse to replace the battery in those cases, based on -my- interpretation of the owners manual.

AFAIK warranty is governed by a separate set of warranty terms, nothing to do with the owner's manual.

 

[arijaycomet]

@whitex -- it sounds like we have similar backgrounds and experiences as I've owned every Tesla S3XY + my 2010 Roadster. Some were leases, others purchases. And overall I'd say you/I have a similar approach to our day to day use of our vehicles, so kudos for our alike thinking there.

FWIW, I think the OP leasing is a valuable tidbit of data, but opens up another question: it is socially irresponsible to not take good care of something during your ownership?

Chances seem slim that in a lease period (typically 36-48 months) that the battery would wear prematurely, or notably. Even if all the charges were DC/fast. But that isn't really "paying it forward" onto the next owner(s) by doing that, is it? That said, I think we get into a discussion there which may be difficult to reconcile in this medium. Still personally when we leased our first EV (Nissan Leaf, 74 miles of range) -- it was only a lease but I still did the same as you said, only charging to 80% in that case on that car, with timed end finish charging to 100% when exclusively required for my day's travel plans. It was a pain, but I knew it would ensure the battery health was ideal (our annual dealer visits even confirmed this).

As you said, the warranty terms might differ from the owners manual.. And one's social conscious on a leased vehicle likely differs than that of someone who bought/owns there car, too. I assume Tesla still pops up an on screen warning when you successively charge to 100% SOC warning you of the ramifications; that alone might help some people turn it down. Porsche probably doesn't do that -- and maybe that is ok. But at the end of the day, trusting consumers to do the right thing is probably not the path most likely to meet with success

 

[Tooney]

I’ve charged to 98% or 99% a few times at EA. Doesn’t slow down all that much. Since EA was so slow to begin with, rarely getting even close to the triple digits!
And it’s all free. At 29 minutes, unplug, then plug back in!

They actually allow DC fast chargers in New England and NE US?
At least they throttle them down there, as revenge.

 

[Jonathan S.]

They actually allow DC fast chargers in New England and NE US?
At least they throttle them down there, as revenge.

Yes. As in, faster than the typical 3kW ChargePoint L2 public unit.
Plus you can get quite a few kWh at the ABB R&D facility in Bloomfield CT before the security guard arrives. (Ask my wife for details on this inadvertent strategy!)
Plus once the Auburn Mall EA was experiencing some sort of malfunction and delivered in the triple digits.
(Fortunately the Magic Docks are not subject to the same restrictions, or at least Elon is flouting the rules.)

 

[jvdsanden]

Sorry guys, maybe has been discussed previously but close to getting a GTS. Simple question to more experience owners, why not charge to 85% and not to 100% every time? Hear me out, on other cars (or electronic devices per se) like Tesla you dont want charge to 100% every time to preserve the battery, HOWEVER, Tesla allows you to use 100% of the battery capacity. On the Taycan only roughly 90% is available to the driver (dont have the exact numbers), remaining 10% are a buffer locked by Porsche.

That begs the question, even if you charge to 100% you never actually charge the battery capacity technically to 100% but only 90%. So why the caution?

If anyone is wondering why ask this question… live close to an EA charger and would charge the car for free…makes more sense to charge to 100% to have less trips to the charger.

FYI, for the Tesla model 3 from China production is adviced to charge always to 100% and not 85%...

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