Long Term Battery Costs, Fears, and Serviceability

[AAKEE]

I have a question about super charging

Everyone is going to eventually take road trips during their cars life so I think it would be good to know best practices for super charging

Some trips I take could easily require 2 - 3 super charges in a single day

Is there a certain battery % that you want to start or stop at during super charging to reduce the strain

There’s really no difference. Low SOC, smaller cycles.

The higher the SOC, the more the cells are prone to lithium plating. Tesla reduces the charging rate at higher SOC, but anyway its most probably not a big difference to other cycling. From my point of view, always precondition completely.

A good thing is that this actually about the same as the fastest way of traveling with supercharging.


Let it go low (only the personal lower limit for range anxiety) and do not charge more than needed to next charger.

But as before, for most people the cyclic aging will be small anyway. You will not notice any difference from your trips.
Using Scan My Tesla you might se that the nominal capacity goes down 0.5-1kWh after several supercharging sessions but when using the low SOC strategy you will see it recover that capacity after some time of low SOC cycling (thats my experience from both the M3P and the MSP).

I again would like to emphrase that to not let the efforts to reduce degradation go to far. Do not let it take the fun out of having an EV.
Using the low SOC strategy will anyway put you ahead of anyone using the regular 80% charging.

While it could be nice to see how far it would be possible to reduce the degratation to, that level would still not be very much lower than anyone using the low SOC strategy. So driving it to the extreme will only save juuuust a little more degradation.

 

[pyrosci]

What is the purpose of reducing degradation, is it resale value? Keeping the car for your kids to inherit?

Or is it to maintain maximum theoretical range?

What is the purpose of maintaining max theoretical range, if you have to put up with low usable range in the first place?

 

[gottagofast]

What is the purpose of reducing degradation, is it resale value? Keeping the car for your kids to inherit?

Or is it to maintain maximum theoretical range?

What is the purpose of maintaining max theoretical range, if you have to put up with low usable range in the first place?

So that when my car is 10 years old I can still make long trips with only 2 super charger stops instead of 4 - 5

 

[LostVector]

What is the purpose of reducing degradation, is it resale value? Keeping the car for your kids to inherit?

Or is it to maintain maximum theoretical range?

What is the purpose of maintaining max theoretical range, if you have to put up with low usable range in the first place?

I don’t know what you mean by “putting up with low usable range”. If I only need to drive 50 miles, whether or not I have 100 miles or 300 miles of range in my battery makes no difference.

I know roughly the range I need for the day, so I just keep the car charged above that. It’s that simple. The average commute is something like 60 miles a day and even at 50% I have 160 EPA rated miles of range. This isn’t a phone where we are using up most of the battery throughout the day.

 

[AAKEE]

What is the purpose of reducing degradation, is it resale value? Keeping the car for your kids to inherit?

Or is it to maintain maximum theoretical range?

What is the purpose of maintaining max theoretical range, if you have to put up with low usable range in the first place?

The purpose might differ from person to person. Most people do not preserve range, or actually think they do just that by keeping 80% daily.

If you can not find a reason, just do not do it.

I use the low SOC stategy (I use 55% daily) on the days I do not need more. I never notice a low usable range as I do not need more most of the days and whenever I need more, I charge more. I can charge at home, so the car begins any ”daily” day with 55%.

For driving to work (240 or 300km) or to my mother in law (250km), I of course charge more. In many of these cases I charge to 100% before the trip.

Going to my grandmother, 250km and no really good charging at her place (travel charger at 2-3kW) and we also most often need to drive around after arrival so the time to charge is (too) short so in wintertime with ~ -20C– -30C it just about covers the needs. Loosing 10% would be noticable.

Keeping low SOC mostly also reduces the increase of the internal resistance.
The increase of internal resistance will longterm reduce the available power and reducing that means less power loss over time. Mostly interresting for people having a Performance model that like to preserve the power.

 

[Bouba]

What is the purpose of reducing degradation, is it resale value? Keeping the car for your kids to inherit?

Or is it to maintain maximum theoretical range?

What is the purpose of maintaining max theoretical range, if you have to put up with low usable range in the first place?

It’s because we are nerds....that 1 mile drop in range means nothing to the vast majority of Tesla owners....we are the minority who worry about everything, listen to every conspiracy theory on battery longevity...but I’m not sure why I’m here

 

[pyrosci]

If I only need to drive 50 miles, whether or not I have 100 miles or 300 miles of range in my battery makes no difference.

Difference is charging once a week vs 5 times a week.

Difference also is you have very little buffer for changed plans.

This did get me thinking, the EV charging process isn't as easy as a phone which is currently the only thing I charge daily. Perhaps some have managed to set up their charging to be super easy and convenient. Mine is ok, it is in a garage but slightly cramped. Also my car's charge port is opposite side to the driver which can be annoying.

I never notice a low usable range as I do not need more most of the days and whenever I need more, I charge more.

I tried 50% charge limit for a little while, and found it removed some spontaneity in my use of the car, and therefore enjoyment. As you say preferences differ, and 80+% charge limit has worked ok for me. Less plugging more driving.

Keeping low SOC mostly also reduces the increase of the internal resistance.

I suppose this matters most with plaid and performance variants. Good point.

 

[AAKEE]

listen to every conspiracy theory on battery longevity...but I’m not sure why I’m here

I know absolutely why I’m writing about it.

I had learned the basics about lithium batteries long time before I got my first Tesla. (Due to use of these batteries in a hobby).
While I started to read forums (like TMC and local forums) I found a big discrepancy between what I had learned earlier by reading research and what the forums said.
After starting reading research once more (a lot) I could safely say that the things said in forums was not true.

So I decided to try to share this knowledge, so people at least would not think they reduced degradation when they actually made the opposite.

So my goal is that people make their choices bases on facts instead of myths (regardless of the charging level they choose).

In this forum I think the knowledge is good. Enough people knows, to counter the myths.

Facebook groups is very hard. Everyone is 100% convinced they know, but it is mostly the myths they spread.
Trying to correct people’s statements is apparently like mentally stabbing a knife in their heart as “everybody knows”….

 

[AAKEE]

For the ones that can do daily charging at home I think it might be good to reflect about the difference between ICE and EV.

If I had to charge away from home I might charge much higher and not every day as it would cost me time. This is about the same as an ICE which need to be refueled away from home.
Charging at home I only need the daily amount plus a reasonable spare. (Knowing 0% is 100% safe, I do not need to have the spare plus another 20% below.)

I guess most people do not withdraw money from an ATM any more, but back at the days when cash was needed most people wouldnt withdraw all the money they had and put it in the wallet.
Most people would probably withdraw about the amount needed (with a slight margin) until the next ATM visit.
Why wouldnt we withdraw all the months sallary an only need to visit the once?
Yes, doing so might cause some disadvantages or risks so we would rather minimize the risk and go another time to the ATM. How often we went to the ATM and how much spare cash we had was a matter of personal choice, just like the charging level and the “spare miles” in the car.

 

[Bouba]

I know absolutely why I’m writing about it.

I had learned the basics about lithium batteries long time before I got my first Tesla. (Due to use of these batteries in a hobby).
While I started to read forums (like TMC and local forums) I found a big discrepancy between what I had learned earlier by reading research and what the forums said.
After starting reading research once more (a lot) I could safely say that the things said in forums was not true.

So I decided to try to share this knowledge, so people at least would not think they reduced degradation when they actually made the opposite.

So my goal is that people make their choices bases on facts instead of myths (regardless of the charging level they choose).

In this forum I think the knowledge is good. Enough people knows, to counter the myths.

Facebook groups is very hard. Everyone is 100% convinced they know, but it is mostly the myths they spread.
Trying to correct people’s statements is apparently like mentally stabbing a knife in their heart as “everybody knows”….

AAKEE, you are a nerd.....but you are our head nerd...and we listen to every word that you say....I can’t imagine what people here would be getting up to without your research and interpretation of complex papers

 

[gottagofast]

Is there a reason Tesla says to leave the vehicle plugged up even when you aren’t using it?

I only lose like 1 mile per day in range when it’s not plugged up I don’t see the reason to keep in plugged up unless I’m not going to be driving it for 6 months

 

[dhrivnak]

Is there a reason Tesla says to leave the vehicle plugged up even when you aren’t using it?

I only lose like 1 mile per day in range when it’s not plugged up I don’t see the reason to keep in plugged up unless I’m going to be driving it for 6 months

Stuff happens and there is NO downside to leaving it plugged in. So why not?

 

[Mercimek]

Is there a reason Tesla says to leave the vehicle plugged up even when you aren’t using it?

I only lose like 1 mile per day in range when it’s not plugged up I don’t see the reason to keep in plugged up unless I’m not going to be driving it for 6 months

It can use the mains to heat/cool battery, as well as precondition the climate or overheat protection. Also sentry mode.

 

[Zythryn]

Is there a reason Tesla says to leave the vehicle plugged up even when you aren’t using it?

I only lose like 1 mile per day in range when it’s not plugged up I don’t see the reason to keep in plugged up unless I’m not going to be driving it for 6 months

It also helps develope the habit of plugging in. Allows the car to rebalance as needed. And as previously said, makes sure something out of the ordinary doesn’t leave you with an unexpected short range.

Also most of the previous discussion does not apply to the LFP batteries in some of the standard range vehicles.

When in doubt, read the manual

 

[AAKEE]

Is there a reason Tesla says to leave the vehicle plugged up even when you aren’t using it?

If you read all information about the battery in the manual, you will find that it is:

-Very few do and dont’s
-There is no differentiated ditos for different climates.
-There is not really differentiated advices for leaving overnight or long term.

The advices Tesla gives seems balanced and spot on for the big picture.

It should be important for us to realize that the advices is not mainly focused on low degradation.

If Tesla said “0% will give the least degradation” there would probably be people that get stranded from the Hv batt disconnecting, (leaving the cars for all kind of time frames) which would cause bad rumors about being out of juice.

The advices are of course aiming to give as many people as little trouble as possible.
Tesla says to account for 1% per day when the car is left for longer time.
IRL, the real consumption are about 0.1% per day - but 1% per day is very easy and gives a good safety margin.

Long term, the cycles will be less as used energy is drawn from the electric net.

The total easy going tip to just about *anyone* would be to always connect the car.

I always connect the car when I am at home, but for longer trips without the car, I leave it not connected and preferably with low SOC. This assures no thunderstorm lightning hot the car via the electric net summertime, and also that it stays at low SOC.

 

[Bouba]

I suspect that the advice to keep it plugged might partly be from when the cars had 12v lead acid batteries that were notorious for failing

 

[LostVector]

Difference is charging once a week vs 5 times a week.

Difference also is you have very little buffer for changed plans.

This did get me thinking, the EV charging process isn't as easy as a phone which is currently the only thing I charge daily. Perhaps some have managed to set up their charging to be super easy and convenient. Mine is ok, it is in a garage but slightly cramped. Also my car's charge port is opposite side to the driver which can be annoying.

Yes, well, there's a very large number of folks here, including myself, for whom it is simple and easy to plug in every night. Having to plug in more is a non issue for most Tesla owners. 80% of Tesla owners charge at home, according to CNBC.

 

[pyrosci]

It is even simpler to charge once a week, charge fully in 4 hours, so car is untethered 99% of its life.

 

[LostVector]

It is even simpler to charge once a week, charge fully in 4 hours, so car is untethered 99% of its life.

Completely disagree.

 

[Sweed269]

I keep mine at 55% and plug in every night. If I need to heat/cool then it pulls from the grid.
If for some reason I need more range I pull up the app and charge it for my longer trip. Easy peasy.