Honest question about battery degradation...

[Zcd1]

I struggle to understand why anyone would be obsessed with or care much about battery degradation...

Tesla provides a warranty that addresses extreme capacity loss, in the unlikely event that such loss occurs.

Teslas use lithium-ion batteries, which like all batteries suffer from some amount of capacity loss over time and through hundreds or thousands of charging cycles. Charging per Tesla's recommendations should enable the least battery degradation and the longest overall battery life.

Even if a car loses 10% (20-30 miles) of its range over 5-7 years, how would that materially impact peoples' daily lives with their cars? Are there that many people who drive their cars 200+ miles a day, every day, and who couldn't spend an extra 5-10 minutes at a Supercharger if the need arose?

I understand that there are "edge case scenarios" where such degradation would have an impact, but even for me, who drives 400 miles each way multiple times a year, 10% range loss would only mean an extra 10-15 minutes of Supercharging time per trip. Hardly a deal-breaker, IMHO.

So please, help me understand an obsession with battery degradation/range loss.

Thx.

 

[jjrandorin]

I am leaning VERY heavily at moving this post to the thread I believe it belongs to, which is here:

MASTER THREAD: Range Loss Over Time, What Can Be Expected, How to Maintain Battery Health

I am willing to be convinced that this somehow needs to be a separate post instead of in that thread, but will be honest that it will need to be either a convincing argument from OP or interaction from several people thinking it needs to remain a separate thread.

 

[Zcd1]

...I am willing to be convinced that this somehow needs to be a separate post instead of in that thread...

The topic of that thread is not at all the same as the topic of this thread, IMHO - that's why I created a separate thread and didn't tack onto that one.

I'm asking why people actually care that much about battery degradation, not about what to expect, or about ways to "fix" it or deal with it.

I'm genuinely interested in hearing people's thoughts on the topic.

 

[glide]

Tesla provides a warranty that addresses extreme capacity loss, in the unlikely event that such loss occurs.

So please, help me understand an obsession with battery degradation/range loss.

Thx.

Good luck getting Tesla to honor that warranty.

An extra 5-10 minutes at the SC? Try an extra hour. Per stop. Then factor that into a road trip requiring multiple stops.

Battery degradation is a real issue on older vehicles and Tesla makes it very clear they do not stand behind their product.

Go read some of the 600+ page thread on battery gate/charge gate if you really want an answer.

 

[jjrandorin]

The topic of that thread is not at all the same as the topic of this thread, IMHO - that's why I created a separate thread and didn't tack onto that one.

I'm asking why people actually care that much about battery degradation, not about what to expect, or about ways to "fix" it or deal with it.

I'm genuinely interested in hearing people's thoughts on the topic.

Its about the topic of "battery degradation" and your question is similar to asking "Why did you vote for so and so? Help me understand." or "why would anyone worry about wearing a mask? help me understand".

Asking why some people are passionate about the biggest part of their expensive car and to explain it to you is not a productive disucssion, in my opinion. I personally am not, by the way, but understand why people are. There is virtually zero chance that a thread with this topic remains a civil discussion.

 

[KenC]

People care about degradation because Tesla sells various models configured with different size batteries. If you pay for a larger battery, with more range, if your larger battery degrades, so its range is more like a mid-size battery, you feel that that extra money was wasted. That's why people seem to care, more than would seem normal.

 

[P85_DA]

The forum is filled weekly with new owners asking similar question about “loss of miles,” charging habits etc ..than there is the 600+ battery gate/charger gate thread ..I have been personally nerfed by the BMS due to my driving habits ..and according to my lifetime stats ..have ~ 9% “degradation ..as another poster mentioned doesn’t really matter to me I enjoy the car ...the battery will never retain the epa ratings beyond a. Few charges it will start to fluctuate etc the displayed “range” I can’t answer why people have such an obsession with this but i would like the mods to consolidate or eliminate a lot of the clutter on the forums that occurs weekly when similar type threads appear

 

[AllanO]

In response to the "why care about the battery when we have a guarantee" question (and yes, this question deserves its own thread):

I have a guarantee of having 70% of original capacity left after the first 160,000 km - which in my case is 5 years.

So let us say that I abuse the battery and have 80% left after 5 years.
You treat your battery well and have 90% left after 5 years.

How did the guarantee make a difference? My battery is in a worse condition that yours, but we are both fine according to the guarantee.

Your car will be easier to sell than my car, because you can show that you have more usable battery left.

So I think it makes a lot of sense to take care of the battery.

 

[P85_DA]

So I think it makes a lot of sense to take care of the batter

I guess different philosophies ...I bought the car to use and drive as normal as possible as I had with an ICE ..that said the OP I guess was asking about people’s obsessiveness with “babying” the batteries etc ...I maintain reasonable charging habits but don’t obsess if I see my range drop few miles here and there ..also I can’t control what Tesla does with software ..look at the 600 page plus thread I’m sure many folks took care of their batteries but that didn’t prevent Tesla from adjusting via software ..I am still of the train of thought I drive my car and charge what I need to use

 

[Black306]

Pretty easy for me to understand why someone who spent a chunk of money, upwards of 70k, would care about degradation. :shrug:

What makes matters worse is we are given the means to check a car’s health. ICE cars don’t have an onboard dyno to report engine health. If there were, I’d bet similar threads would pop up. “Oh no! My 700 hp car is only making 693 after 8 months and 7k miles!? The world is going to end!!”

Personally, this is why I put the ‘gauge’ to % right off the lot; I’m not going to worry about a mile here and there. I’d rather just enjoy the car.

 

[jjrandorin]

I guess different philosophies ...I bought the car to use and drive as normal as possible as I had with an ICE ..that said the OP I guess was asking about people’s obsessiveness with “babying” the batteries etc ...I maintain reasonable charging habits but don’t obsess if I see my range drop few miles here and there ..also I can’t control what Tesla does with software ..look at the 600 page plus thread I’m sure many folks took care of their batteries but that didn’t prevent Tesla from adjusting via software ..I am still of the train of thought I drive my car and charge what I need to use

A lot of people in this section of TMC are not aware of what happened with the model S (I am, even though I drive a model 3).

I had a lot typed here, and realized I was doing exactly what I said was counter productive in my earlier post in this thread. I will summarize to say, its understandable that people obsess over expensive purchases, even if the obsession is irrational, or based in irrational fears.

===========================

Putting the mod hat on for a minute, I am going to leave this post here for now, but going to keep an eye on it.

 

[Zcd1]

I actually am aware of what happened with some Model Ss. The newer battery technology was one of the reasons I bought a new Model 3 rather than a slightly used Model S.

The reason I asked the question though is that I've never understood the value of obsessively tracking the battery capacity down to the single digit percentage. As others have mentioned, I switched my display to percentage instead of miles remaining the 2nd day I had the car, and I simply charge when necessary. If the car takes an extra few minutes (or dollars) to charge overnight or at a Supercharger, the way I see it, who cares? I'm still so far ahead of the energy cost of owning a comparable ICE vehicle that a the extra time or cost don't matter in the larger scheme of things.

Charge rate nerfing on Tesla's part is a different question altogether, and not what I was asking about at all.

 

[outdoors]

People care because it is something they don't understand or have been told/read to worry about. Change is hard for many. People are creatures of habit, especially in something mind numbing as filling a tank of gas. Dad did it. So did Grandad. Rinse repeat. Completely understandable. Doubt few owners of a Subaru would ask at 83k in miles what exactly is the efficiency of my car compared to new to the point of measurement. Some maybe, but I would say few. I was one of those people. Now I use TeslaFi on one of the cars we own. Interesting data.

 

[AllanO]

The reason I asked the question though is that I've never understood the value of obsessively tracking the battery capacity down to the single digit percentage.

OK. Then I misunderstood you. I thought you were talking about taking care of the battery, in order to avoid causing unnecessary degeneration.

I agree regarding the obsession on actually tracking the degeneration. That is rather silly. But on the other hand, I am used to seeing people obsess over numbers, which have sufficient information value to let them draw the wrong conclusions. Not much to do about that.

 

[alexgr]

I struggle to understand why anyone would be obsessed with or care much about battery degradation...

Resale value.

 

[GtiMart]

We all agree that taking good care of a car is a good thing, for personal usage and for resale value There are good practices and there are obsessions. You must simply learn to differentiate both, just like in the ICE car world. Use the car, it's not a decoration. Do read the forums, learn the guidelines. Follow the general rules and you'll be fine.

 

[Zcd1]

People care about degradation because Tesla sells various models configured with different size batteries. If you pay for a larger battery, with more range, if your larger battery degrades, so its range is more like a mid-size battery, you feel that that extra money was wasted. That's why people seem to care, more than would seem normal.

Every version will see some degradation, so the range gap between the versions will remain roughly the same, right?

So I’m not sure I understand the point you’re trying to make...

 

[GtiMart]

Zcd1, you're right for the most part. 7% is 7%, but 7% of 300 miles is more than 7% of 200 miles (21 vs 14). A bigger battery has more cells, and each cell degrades a bit. Still, a degraded big battery will still have more range than a degraded small battery.
If you want to eke out as much life as possible, you can obsess to the point of limiting your usage and appreciation of the car. Just know that the car has an excellent BMS that will handle most of the important battery life reduction factors for you automatically.

There are exceptions where batteries are really bad and that's what the warranty is for. There will be small discrepancies between total kWh capacity of otherwise equivalent batteries, just like there are discrepancies between the horsepower of engines in ICE cars, yet most people don't dyno their car so they don't know. We must learn to live with that, otherwise we will all have panic attacks every time the guess-o-meter changes its value Because yes, even the battery percentage or rated range indicator is a guess of how much power remains in the battery.

 

[KenC]

Every version will see some degradation, so the range gap between the versions will remain roughly the same, right?

So I’m not sure I understand the point you’re trying to make...

As a group, all battery sizes will follow the same trends; but people only have their individual vehicle experiences. They see their car suffering battery deg, and read about other people not having any deg. My battery is two years old, and it lives outdoors in the Summer heat, and the Winter cold, and I've seen zero visible deg. People with deg read that, and want to have a battery like that. Batteries with minimal deg. They want to be on the positive side of the bell curve not on the negative side. It makes them feel like they've done something wrong, and when they know they've done nothing wrong, they feel cheated.

The variation I've seen has been all temperature related. In the past week, I have a dot at 312 miles, and one below 290 miles, when we had a blue snowflake day. You can see the trend line is almost perfectly horizontal. People want that battery. Of course, my battery deg could fall off a cliff tomorrow.

 

[hcdavis3]

A lot of people in this section of TMC are not aware of what happened with the model S (I am, even though I drive a model 3).

I had a lot typed here, and realized I was doing exactly what I said was counter productive in my earlier post in this thread. I will summarize to say, its understandable that people obsess over expensive purchases, even if the obsession is irrational, or based in irrational fears.

===========================

Putting the mod hat on for a minute, I am going to leave this post here for now, but going to keep an eye on it.

I agree with you jj. But for me it’s a matter of getting what I paid for i have close to 7% degradation in 5 months and 4000 miles.