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

[AlanSubie4Life]

Yeah, sounds like that 264 @ 90% is pretty solid now. Definitely in some cases a few miles missing might be due to rebalancing, but it doesn't reflect reality to expect a 254@90% number to magically regain its 279@90% former glory if you just obey some "set 90% and forget it" mentality. Loss of capacity is real, and quite irreversible!

Expect about 10%...you won't be disappointed.

 

[dmurphy]

Yeah, sounds like that 264 @ 90% is pretty solid now. Definitely in some cases a few miles missing might be due to rebalancing, but it doesn't reflect reality to expect a 254@90% number to magically regain its 279@90% former glory if you just obey some "set 90% and forget it" mentality. Loss of capacity is real, and quite irreversible!

Expect about 10%...you won't be disappointed.

all I can say is that after almost a year and over 12,500 miles, my battery still charges to 276 @ 90%. And it’s below freezing outside; suspect it’ll be a little higher once spring arrives.

Others who just charge to 90% every day (you know who you are) are seeing similar results.

 

[Zoomit]

set it at 90% and forget it. That’s what rebalances the bricks.

BMS calibration and brick rebalancing are two different concerns, with separate lineages of hearsay and “wives’ tales” to follow.

 

[dmurphy]

BMS calibration and brick rebalancing are two different concerns, with separate lineages of hearsay and “wives’ tales” to follow.

You are absolutely right, intertwined but not directly linear.

What I can say is that the “charge to 90%” bit to enable brick rebalancing is definitely hearsay or a wives’ tale. It’s well documented by Tesla, including the formula the BMS controller uses.

 

[AlanSubie4Life]

all I can say is that after almost a year and over 12,500 miles, my battery still charges to 276 @ 90%. And it’s below freezing outside; suspect it’ll be a little higher once spring arrives.

Others who just charge to 90% every day (you know who you are) are seeing similar results.

And I always say - everyone is part of the distribution. Just because you have a good battery does not mean that your charging method is optimal. It is likely good luck. There is certainly nothing wrong with charging to 90% and leaving it. I do it all the time. 300 miles at 13700 miles and 15 months. About 6% loss (not due to cold) of capacity vs your ~4% (perhaps impacted by cold). (Depends on what your initial capacity was, which is unknown but was likely above 78kWh.)

 

[DrLegoHair]

Well, I hope this is not the case for you guys but my battery started degrading rapidly after 20,000 miles. Prior to that my degradation was only 3-4% and then within a span of a few months and 4000 miles I am looking at >10%.

Hopefully it levels off here... Although it has dropped another 1 mile since my post earlier today

 

[benjijk]

SR+ model 3 purchased in July. Battery at 90% used to be around 212 and 100% at 240. Now 100% shows 231 miles and 90% only reaches 208. Is this something I need to worry about? The car's only about 7 months old.

 

[AlanSubie4Life]

SR+ model 3 purchased in July. Battery at 90% used to be around 212 and 100% at 240. Now 100% shows 231 miles and 90% only reaches 208. Is this something I need to worry about? The car's only about 7 months old.

Normal! Expect it to get as high as about 10%...about 218 rated miles at 100%. Should definitely slow down by then.

 

[N54TT]

Update at 19000 miles/16months. I just charged to 100% yesterday for a ski trip and got 293 miles. Remote for Tesla displays 72 kwh(does api report this...or is it calculated some how by the app?). For the past 2k miles or so, I’ve only been opening Tesla Stats app right after end of charge....to trigger it capturing data then. Otherwise it’s too random and lends to much greater variability in battery capacity.....because it normally captures it in different parts of the the percentage point. Here’s my graph as of today. Can see the latest data points are much more clustered together.

Charging habits: typically drive 45miles a day and charged between 80-90 percent. Lately if I’ve been timing my charge to end in the morning before leaving...so it doesn’t sit at a higher charge all night.

 

[AlanSubie4Life]

Update at 19000 miles/16months. I just charged to 100% yesterday for a ski trip and got 293 miles. Remote for Tesla displays 72 kwh(does api report this...or is it calculated some how by the app?). For the past 2k miles or so, I’ve only been opening Tesla Stats app right after end of charge....to trigger it capturing data then. Otherwise it’s too random and lends to much greater variability in battery capacity.....because it normally captures it in different parts of the the percentage point. Here’s my graph as of today. Can see the latest data points are much more clustered together.

Charging habits: typically drive 45miles a day and charged between 80-90 percent. Lately if I’ve been timing my charge to end in the morning before leaving...so it doesn’t sit at a higher charge all night.

View attachment 507062

Cool. Stats should provide this ability as an option itself...would not be hard...

 

[N54TT]

Cool. Stats should provide this ability as an option itself...would not be hard...

He has also stated that he uses “real soc” which I’m presuming is battery_level reading and not usable_battery_level. Which makes sense that what Stats reports is sometimes different than what the car and the Tesla app reports. So when the battery is cold I find that Stats shows a much lower battery capacity. I find that collecting battery capacity when the battery is warm..ie after charging (more so during colder winter months) also helps to make that data collection more consistent as well.

 

[dmurphy]

He has also stated that he uses “real soc” which I’m presuming is battery_level reading and not usable_battery_level. Which makes sense that what Stats reports is sometimes different than what the car and the Tesla app reports. So when the battery is cold I find that Stats shows a much lower battery capacity. I find that collecting battery capacity when the battery is warm..ie after charging (more so during colder winter months) also helps to make that data collection more consistent as well.

12,232 miles and here's my Stats chart... I do expect it to go up a little bit come springtime. You can see the (small) drop in average was around 9000 miles or so. That was November, when the weather started getting colder.

Still, here in February, 275mi @ 90% state of charge.

 

[pdx_m3s]

I wish Tesla would just be transparent about degradation and give customers a degradation percentage somewhere in the UI, just like Apple did with iPhone.

 

[dmurphy]

I wish Tesla would just be transparent about degradation and give customers a degradation percentage somewhere in the UI, just like Apple did with iPhone.

The lawsuits that would ensue from the TSLAQ crowd would be astronomical ....

 

[pdx_m3s]

The lawsuits that would ensue from the TSLAQ crowd would be astronomical ....

Completely disagree. More information can only be a good thing. The less people feel likeTesla is hiding something the better.

 

[ran349]

Update at 19000 miles/16months. I just charged to 100% yesterday for a ski trip and got 293 miles. Remote for Tesla displays 72 kwh(does api report this...or is it calculated some how by the app?). For the past 2k miles or so, I’ve only been opening Tesla Stats app right after end of charge....to trigger it capturing data then. Otherwise it’s too random and lends to much greater variability in battery capacity.....because it normally captures it in different parts of the the percentage point. Here’s my graph as of today. Can see the latest data points are much more clustered together.

Charging habits: typically drive 45miles a day and charged between 80-90 percent. Lately if I’ve been timing my charge to end in the morning before leaving...so it doesn’t sit at a higher charge all night.

Remote for Tesla calculates the 72 kWh pack value. It is not provided by the API. It will therefore have some variability due to rounding errors when the app calculates the value. But on average, it is a pretty good approximation, and it will trend with the actual value as your battery degrades. You would need SMT or TM-Spy to get the actual correct value per the BMS.

 

[dmurphy]

Completely disagree. More information can only be a good thing. The less people feel likeTesla is hiding something the better.

Totally OK to disagree, but I don’t believe more data is “always” better. Very very easy to misinterpret.

Putting a “battery has lost 7% of its capacity” indicator would be seized and blown way way out of proportion by the antiTSLA crowd.

 

[ku7tech]

In the past 16500 km ( 10000 miles) and 4 months of ownership, this has been my trend.

I've been to 100% once, about 13,000 on the odo
And I've only been under 20% 4 or so times ever.
Twice in the past couple thousand

It's been summer the entire 4 months of ownership.

After some thoughts on this.
I work with lithium batteries and this to me does not look like degradation. Either there's some very bad cells not showing up as imbalance,o its something else.

 

[AlanSubie4Life]

Remote for Tesla calculates the 72 kWh pack value.

Yep. 293rmi*245Wh/rmi = 71.8kWh.

@N54TT, it is usually pretty close from what I have seen people report from their SMT/etc. readbacks. Just have to use the appropriate constant for your vehicle (covered elsewhere!).

 

[TwoK4drSi]

Yeah, sounds like that 264 @ 90% is pretty solid now. Definitely in some cases a few miles missing might be due to rebalancing, but it doesn't reflect reality to expect a 254@90% number to magically regain its 279@90% former glory if you just obey some "set 90% and forget it" mentality. Loss of capacity is real, and quite irreversible!

Expect about 10%...you won't be disappointed.

Is that LRAWD numbers? I’m at 285@100. I switched to percentage a long time ago and decided to check on it. Little concerned now.