Range Loss Over Time, What Can Be Expected, Efficiency, How to Maintain Battery Health

[electrictorque]

Over the weekend I did a 240 miles round-trip with an overnight stay.

Charged to 100% prior the start of the trip and it showed 288 miles range.

Drove 120 miles mostly @74 mph and temp set to 72 outside was 33.

Got to destination with 49% SOC

on the way back I stopped to super charge for exactly 10 minutes and got home with 9% SOC.

 

[adaminfl]

One data point doesn’t mean it’s a trend. Curious to see how this plays out over the next few days, but after upgrading to the latest firmware I’ve experienced what I think is substantial loss. Thoughts here?

 

[Rhytid]

One data point doesn’t mean it’s a trend. Curious to see how this plays out over the next few days, but after upgrading to the latest firmware I’ve experienced what I think is substantial loss. Thoughts here?View attachment 492721

I posted in the Master thread. I noticed the same thing.
My 90% went from 279 to 265 with the new update.
That’s theoretically a 4.5% drop.

So that’s at least 2 data points.

 

[1.21GW]

I posted in the Master thread. I noticed the same thing.
My 90% went from 279 to 265 with the new update.
That’s theoretically a 4.5% drop.

So that’s at least 2 data points.

That happened to my car in a previous update. My 90% has been 265 for a few months now. (LR AWD)

 

[rkinney]

That happened to my car in a previous update. My 90% has been 265 for a few months now. (LR AWD)

 

[flyingowl]

Sigh... if tesla will keep up with kind of updates, they will replacing half of batteries in 3-4 years. I wonder if it's because FSD eats more power...

 

[adaminfl]

No FSD here.

 

[rkinney]

I have a 2020 M3 stealth that I picked up a few weeks ago. My 90% was 279 miles pre update checking today after update I now show 90% at 267 miles. Car is in the garage where temperature has remained consistent around 51 degrees so this could be a change in software calculations on the new update?

I’m new to EV range and this doesn’t alarm as much as others as I assume the software engineers are constantly adjusting as data comes in from the active community to refine accuracy. My first commute to work was exactly 50 miles but I used 89 miles of range. This included pre-warming the car at the office before running to lunch and before heading home......a stomp on the accelerator to show my lunch guest the great fun the car can provide, and sitting outside my office during my 10 hour work day so some additional drain.

I doubt in the last 2 weeks the physical properties of my battery have changed so this must be an update in how the software is calculating range. Maybe it is adapting to my personal driving environment to understand my personal habits along with ambient temperature to give a more accurate forecast of my personal range?

 

[ran349]

No FSD here.

You drove 11 miles and recharged to 90%? The BMS may just be confused following the update.

 

[follow.johnny]

I just finished charging to 90% this morning and checked the miles and it reads 279 miles. I know every update typically has a new BMS update that needs to be recalibrated based on your driving habits and current battery health.

 

[jjrandorin]

Since OP asks for "thoughts", here is mine.

I find it humorous that OP:

1. Started tracking this via teslafi on 12/13 with 245 miles on the car, making it a fairly decent assumption that delivery of the car happened not too long before that, and
2. OP has driven less than 1k miles total

And still is somehow concerned that he has battery "degradation".

Im going to use an Audio Visual product analogy here. Most of what people are seeing is like people being concerned with "Burn in" on their TV, and calling image retention, "Burn in". They look the same, but Image retention on a TV goes away eventually, while "Burn In" is there permanently, which is why its called "burn" in. This is the phenomenon of having a static image (like a TV station logo, or espn ticker) being visible when you change the channel to a different station.

Why am I saying this is similar?

Because tons and tons (and tons and tons and tons and tons) of people here are confusing "degradation" (which is the permanent loss of battery capacity) with BMS calculation losses. If someones battery has "degraded" with less than 1k miles, then there is a real problem with the battery.. but one is not going to see that from a loss reported by teslafi, and tesla is NOT going to accept any statement such that "Teslafi (or stats, or any other third party tool) shows I have......."

Those tools are mistakes for most new owners, because they just induce fear for many... not all, but many. Its my opinion that the data should be gathered, but not even paid attention to for the first 6-8 weeks of ownership, if one is into gathering all that data. By that time, you can look at trends, etc. Worrying about 1 day that shows a lower max range (without even driving that range to find out), is just stress for no reason.

Since Op asked for "thoughts", those are mine, which I am sure are not likely popular.

 

[thor_2019]

Same before and after, 296mi est @100%, @ 12120mi on ODO. 8 months old.

Give it a good drive then charge again. Watching Teslafi will be a rollercoaster. Just drive the car and don't worry about it.

 

[ChemEJon]

Don’t know why this happened.

 

[Sagester]

Currently estimated 100% range @ 289, i've noticed a steep drop off in estimated range since the original v10 update

I have about 6k miles on it, purchased in july of 2019.

When I first got the car estimated 100% range was 308 miles

Not sure if this represents battery degradation or a software change?

 

[Rhytid]

Currently estimated 100% range @ 289, i've noticed a steep drop off in estimated range since the original v10 update

I have about 6k miles on it, purchased in july of 2019.

When I first got the car estimated 100% range was 308 miles

Not sure if this represents battery degradation or a software change?

Well I guess that’s the real question. How do we, as average users, know what is actual battery degradation vs. software change? And if it ever comes to the point where a battery warranty issue comes up, what objective measure do we use?
The only measure that I am aware of is the distance that is displayed. Obviously you can’t go by percentage as that really doesn’t mean anything.
Again, I am talking about average users. I don’t have access to any other more sophisticated equipment.
My car is barely over 2 weeks old. I am on here to learn and gather information. If I am missing something obvious, let me know.

 

[Ssmtsx]

That happened to my car in a previous update. My 90% has been 265 for a few months now. (LR AWD)

Add me to the list. I was at 247 at 80% I’m down to 236 now.

 

[ChemEJon]

Did this change? Looks like my rated Wh/mi is around 260?

 

[Ssmtsx]

Did this change? Looks like my rated Wh/mi is around 260?

what wheels do you have?

 

[leeeeee]

Because tons and tons (and tons and tons and tons and tons) of people here are confusing "degradation" (which is the permanent loss of battery capacity) with BMS calculation losses. If someones battery has "degraded" with less than 1k miles, then there is a real problem with the battery.. but one is not going to see that from a loss reported by teslafi, and tesla is NOT going to accept any statement such that "Teslafi (or stats, or any other third party tool) shows I have......."

I think TeslaFi would show degradation as understood by the BMS. Certainly the BMS can be wrong but it's the only window into battery health we have. All Teslafi is doing is extrapolating the BMS reported range to an equivalent for 100% charge. This is exactly what most people would be doing to try to guess if their battery is at less than rated range.

 

[AlanSubie4Life]

Since Op asked for "thoughts", those are mine, which I am sure are not likely popular.

Certainly the BMS can be wrong but it's the only window into battery health we have

You can actually carefully measure the trip meter tally relative to miles consumed to draw a conclusion about how much energy was actually in the battery. But you can’t do that over a 10% span of battery consumed. It really needs to be something like a 90-100% discharge down to near 5%.

I’ve seen no evidence on my own car ever that the tally of energy is ever off in any significant way - each rated mile contains about 230Wh for my 3P (within 1%, so my observed loss of rated miles of about 3% is “observable” with this method). You obviously have to not have any significant change in battery temperature during the course of the discharge, as a warming battery gains available energy and will probably throw the calculation off.

In any case my point is that it does seem that a reduction in available miles, whatever the reason, actually does appear to mean a reduction in available energy. (Just keep in mind that a very cold battery, as mentioned above, will always lose available energy temporarily, and this will show as a loss of miles as the battery cools - once it is thoroughly warmed up again they immediately show up again.)

If I had a CAN reader, it would show I had 73.5kWh now, vs. about 76kWh when new. Is this permanent? No idea. However, real degradation is ultimately inevitable and everyone should expect 10% when purchasing their vehicle (and hopefully it then levels off quickly after that first year or two). The sun also rises.