Tesla sets charge limit to 90%

[Stew-2]

My habit is similar, but averages about 10% lower than yours.

I charge @4:00 am to 50%. I arrive at work with about 42%, and the car sits in the hot Florida sun. When I get home I have about 34%, until the recharge at 4:00 am.

This is almost exactly my daily charging and usage routine too.

I’ve got a 2022 M3P, took delivery in Feb ‘22 and has just under 15k miles. A few days ago I charged to 100% (which I only do a couple times a year) and it showed 307 miles, down from 315 when new.

307/315 is 97.5% capacity, or 2.5% degradation, that seems pretty decent, this is in the greater Seattle area with pretty mild weather year round.

 

[Bouba]

As a retiree I don’t do a lot of mileage...but like many here I thought that I needed more charge than I did ‘just in case’....but the science (as expounded by some of our more brilliant forumites) says to keep the charge low to avoid degradation. So gradually I cut back until I kept it at 50%...in order to comply with Tesla’s advice of keeping it plugged in. Today we are going on a road trip (taking a visitor from the States to the Roman town of Arles to go on the Van Gogh trail)...so the car is at 100%...and we will be leaving as soon as I’ve posted this

 

[dafish]

But Elon says 90% or 95% are fine! And no reason to go below 80%. Who are you going to believe?

Now I am just causing problems, adding no value (as is typically the case when posting ElonTweets).

View attachment 936494View attachment 936495

As a retiree I don’t do a lot of mileage...but like many here I thought that I needed more charge than I did ‘just in case’....but the science (as expounded by some of our more brilliant forumites) says to keep the charge low to avoid degradation. So gradually I cut back until I kept it at 50%...in order to comply with Tesla’s advice of keeping it plugged in. Today we are going on a road trip (taking a visitor from the States to the Roman town of Arles to go on the Van Gogh trail)...so the car is at 100%...and we will be leaving as soon as I’ve posted this

I feel like Akee has done a solid job of showing us the best practices and supporting it well, so I do pretty much as Bouba does. I've no need for more, and why not optimize battery longevity?

* I'm always charging back up to 50% when at home.
* I "departure charge" to 57% on work days and condition the cabin& battery at the same time.
* I departure charge to 85% for a long trip, would goto 90% if I had too, will just charge sooner if I need more. I'd just slow down a touch if 90% wasn't enough range. Mostly I plan around 200 mile legs and call it good, for this way I'm not waiting for the slower upper part of the charge cycle.

 

[Hiline]

In the forums i write and read at, and also collegues and friends, there is now a considerable number of cars that have charged to 50-55 (or 60% for NMC cells) since new, and its very easy to se that the low SOC makes an noticable difference in degradation. There is no exemple of a car kept at low SOC that has high degradation. There even is no one that is on the average line. They all do way better than this.

A BMS Calibration shouldnt change anything if the BMS was on track to begin with. Also, a increased range from a BMS calibration does not mean that the battery increased the capacity. Its displayed range only, and the BMS that shows a higher number.

I ran into your posts early in my Tesla ownership. I credit following your advice - keeping state of charge around 60% or lower most of the time - for the relatively slow battery degradation on my Model Y thus far

 

[E90alex]

You can go down to 0% without worrying about affecting the battery health (but there’s other reasons why you may not want to go down that low). It’s staying at high levels of charge that degrades the battery faster.

 

[EVCT]

First time poster. And a newbie Tesla owner. What a great forum. Lots of ideas on charging. Here is my situation…..Juat bought my MYLR a couple of weeks ago and still waiting for the plates to arrive. So I have been driving it locally 10 -15 miles a day and have kept the charge around 50%. Once the plates come I plan on using it for work and work and back is about 180 miles round trip. I will only do that about 7 times a month. And it’s mostly highway driving.
Should I charge it to 100% each time I use it for work? Or should I try to charge it to 95% and get the 180 miles on that percentage? I assume I will get the mileage.
Just looking for ideas on what’s best to get a nice long life from the battery.

Thanks….

 

[E90alex]

First time poster. And a newbie Tesla owner. What a great forum. Lots of ideas on charging. Here is my situation…..Juat bought my MYLR a couple of weeks ago and still waiting for the plates to arrive. So I have been driving it locally 10 -15 miles a day and have kept the charge around 50%. Once the plates come I plan on using it for work and work and back is about 180 miles round trip. I will only do that about 7 times a month. And it’s mostly highway driving.
Should I charge it to 100% each time I use it for work? Or should I try to charge it to 95% and get the 180 miles on that percentage? I assume I will get the mileage.
Just looking for ideas on what’s best to get a nice long life from the battery.

Thanks….

You can use the navigation while at home to set the destination to work and then add another stop back home and see how much charge the car estimates it will take round trip. Then adjust your charge level accordingly.

Or just charge to 100% right before you leave the first day you drive it to work and see what you get home with. Then in the future you can lower it further if you want.

 

[jcanoe]

First time poster. And a newbie Tesla owner. What a great forum. Lots of ideas on charging. Here is my situation…..Juat bought my MYLR a couple of weeks ago and still waiting for the plates to arrive. So I have been driving it locally 10 -15 miles a day and have kept the charge around 50%. Once the plates come I plan on using it for work and work and back is about 180 miles round trip. I will only do that about 7 times a month. And it’s mostly highway driving.
Should I charge it to 100% each time I use it for work? Or should I try to charge it to 95% and get the 180 miles on that percentage? I assume I will get the mileage.
Just looking for ideas on what’s best to get a nice long life from the battery.

Thanks….

New EV owners tend to plan, drive as they would for an ICE vehicle. Instead of charging to 100% and then driving until you are almost at 0% state of charge let the Tesla Model Y's Navigation system guide you on when and where to stop and use a Supercharger station. The Tesla Supercharger network makes range anxiety mostly a non-issue.

A Better Route Planner (ABRP), a third-party software for your phone and web app, lets you customize many variables for your trip and plan your charging stops. ABRP can recommend Tesla Supercharger charging locations and also DC Fast Charge network locations. If you wish to use one of the DC Fast Charge networks such as Electrify America you would need to purchase the Tesla CCS Combo 1 charging adapter ($175 from the Tesla online store) or one of the 3rd-party CCS1 adapters that are available.

For a 180 mile trip I would not bother charging to 100%, not more than 90%. I would plan to charge once near the start of the return trip, arrive back home with a reasonable reserve state of charge, i.e. 15% or 20%.

In winter, if you drive this same 180 mile trip, you will find that the energy consumption will increase by at least 20% as your driving efficiency falls with the lower temperature. Instead of wondering, "will I be able to make it home?" just charge a little longer at the Supercharger (perhaps an additional 20%.)

Another useful phone and web app is Plugshare. Plugshare can locate nearby charging stations, perhaps even close to where you will be traveling and maybe even free to use for a few hours. (A 6kW Level 2 charging station (very common with public L2 charging) would enable you to add 20 miles + per hour to your range for every hour you charge. 4 hours would probably be all the time you would need to charge back to 80% or 90% for the return trip.)

The Tesla Supercharger network is available 24 X 7. There are currently 5,000 Supercharger locations and 50,000 charging connections (globally.) You need a valid credit card or debit card saved to your Tesla Account to use the Supercharger network. (I recommend performing a brief, i.e. 2 minute, Supercharging session at a nearby Supercharger to verify that you can charge your new Tesla Model Y using the Supercharger network. (Probably will cost $0.30 to perform the 2 minute test.)

The initial (maximum) charging rate when Supercharging will vary with the version (generation) of Supercharger, the state of charge of the battery at the beginning of the charging session and the battery temperature. The battery temperature will be automatically optimized for Supercharging when you enter the Supercharger location as the next way point or destination in the Tesla Navigation system and start to drive. That said, you would probably need to charge at a Supercharger for less than 20 minutes to reach your home with a comfortable level of reserve battery charge.

 

[HMHM]

You can go down to 0% without worrying about affecting the battery health (but there’s other reasons why you may not want to go down that low). It’s staying at high levels of charge that degrades the battery faster.

I have a personal experience with my cell phone becoming noticeably hot at a lower SoC. At or below 5% SoC, which probably equates to a cell voltage of 2.7V or less, a thermal runaway can happen. I'm not sure if the Tesla BMS has a built in protection or buffer to protect the battery pack. I hope to get some expert advice to understand the Tesla's BMS capabilities?

 

[E90alex]

I have a personal experience with my cell phone becoming noticeably hot at a lower SoC. At or below 5% SoC, which probably equates to a cell voltage of 2.7V or less, a thermal runaway can happen. I'm not sure if the Tesla BMS has a built in protection or buffer to protect the battery pack. I hope to get some expert advice to understand the Tesla's BMS capabilities?

Never noticed that with any battery device I’ve owned and I’ve never heard of thermal runaway due to low charge, only from over charging.

 

[HMHM]

Never noticed that with any battery device I’ve owned and I’ve never heard of thermal runaway due to low charge, only from over charging.

Thermal runaway issue has been widely documented in pants' pockets and luggage pieces, in Lithium-ion batteries not being charged. Leaving the thermal runaway aside, it's a known fact that a very low cell voltage can cause overheating, and consequently accelerated degradation. In case of an emergency, it's possible to discharge the battery pack down to 0%, or 2.5V, but Tesla's BMS overrides the driver, and prevents the overheating. The BMS shuts down the output from battery pack to motor to prevents the battery pack and the motor from damage/degradation. I hope to get some more expert advice to understand the capabilities of the Tesla's BMS.

 

[EVCT]

New EV owners tend to plan, drive as they would for an ICE vehicle. Instead of charging to 100% and then driving until you are almost at 0% state of charge let the Tesla Model Y's Navigation system guide you on when and where to stop and use a Supercharger station. The Tesla Supercharger network makes range anxiety mostly a non-issue.

A Better Route Planner (ABRP), a third-party software for your phone and web app, lets you customize many variables for your trip and plan your charging stops. ABRP can recommend Tesla Supercharger charging locations and also DC Fast Charge network locations. If you wish to use one of the DC Fast Charge networks such as Electrify America you would need to purchase the Tesla CCS Combo 1 charging adapter ($175 from the Tesla online store) or one of the 3rd-party CCS1 adapters that are available.

For a 180 mile trip I would not bother charging to 100%, not more than 90%. I would plan to charge once near the start of the return trip, arrive back home with a reasonable reserve state of charge, i.e. 15% or 20%.

In winter, if you drive this same 180 mile trip, you will find that the energy consumption will increase by at least 20% as your driving efficiency falls with the lower temperature. Instead of wondering, "will I be able to make it home?" just charge a little longer at the Supercharger (perhaps an additional 20%.)

Another useful phone and web app is Plugshare. Plugshare can locate nearby charging stations, perhaps even close to where you will be traveling and maybe even free to use for a few hours. (A 6kW Level 2 charging station (very common with public L2 charging) would enable you to add 20 miles + per hour to your range for every hour you charge. 4 hours would probably be all the time you would need to charge back to 80% or 90% for the return trip.)

The Tesla Supercharger network is available 24 X 7. There are currently 5,000 Supercharger locations and 50,000 charging connections (globally.) You need a valid credit card or debit card saved to your Tesla Account to use the Supercharger network. (I recommend performing a brief, i.e. 2 minute, Supercharging session at a nearby Supercharger to verify that you can charge your new Tesla Model Y using the Supercharger network. (Probably will cost $0.30 to perform the 2 minute test.)

The initial (maximum) charging rate when Supercharging will vary with the version (generation) of Supercharger, the state of charge of the battery at the beginning of the charging session and the battery temperature. The battery temperature will be automatically optimized for Supercharging when you enter the Supercharger location as the next way point or destination in the Tesla Navigation system and start to drive. That said, you would probably need to charge at a Supercharger for less than 20 minutes to reach your home with a comfortable level of reserve battery charge.

Thanks you for that info….

 

[zoomer0056]

I have always charger to 90% for the eight years I have owned my model s.

What is the % degradation on the battery after 8 years of 90% charging?

 

[EVCT]

You can use the navigation while at home to set the destination to work and then add another stop back home and see how much charge the car estimates it will take round trip. Then adjust your charge level accordingly.

Or just charge to 100% right before you leave the first day you drive it to work and see what you get home with. Then in the future you can lower it further if you want.

Good idea. Thank you.

 

[Rocky_H]

Once the plates come I plan on using it for work and work and back is about 180 miles round trip. I will only do that about 7 times a month. And it’s mostly highway driving.
Should I charge it to 100% each time I use it for work? Or should I try to charge it to 95% and get the 180 miles on that percentage? I assume I will get the mileage.

I'm going to concur with @jcanoe and say I wouldn't do either one of those. New owners do seem to try to go to extremes to try to avoid charging stops. Why? You have access to the best charging network on the planet. Does this 180 mile route really not have ANY Superchargers on it? I start with a normal state of charge, like 80 or 90% and then just plan to take a reasonable 15 minute top-up at a Supercharger on the way there or the way back. It shouldn't be a big deal and wouldn't require overthinking.

 

[Bouba]

I'm going to concur with @jcanoe and say I wouldn't do either one of those. New owners do seem to try to go to extremes to try to avoid charging stops. Why? You have access to the best charging network on the planet. Does this 180 mile route really not have ANY Superchargers on it? I start with a normal state of charge, like 80 or 90% and then just plan to take a reasonable 15 minute top-up at a Supercharger on the way there or the way back. It shouldn't be a big deal and wouldn't require overthinking.

One of the reasons I look forward to road trips is to charge to 100%....not that I need to, like everyone here I am always curious to see what the battery capacity actually is

 

[jcanoe]

One of the reasons I look forward to road trips is to charge to 100%....not that I need to, like everyone here I am always curious to see what the battery capacity actually is

It takes much longer to charge beyond 94 or 95% all the way to 100%. That and the fact that it is not good to routinely charge to 100% for the long term health of the battery and is truly not needed for most road trips.

In 2013 when there were no Superchargers (at least outside of parts of California) you might need to charge to 100%. Now with almost 2,000 North America Supercharger locations (1,966 locations as of April 2023) and the ability to charge at DC Fast Charge stations such as Electrify America using the Tesla CCS Combo 1 adapter charging to 100% is mostly OBE.

 

[Bouba]

It takes much longer to charge beyond 94 or 95% all the way to 100%. That and the fact that it is not good to routinely charge to 100% for the long term health of the battery and is truly not needed for most road trips.

In 2013 when there were no Superchargers (at least outside of parts of California) you might need to charge to 100%. Now with almost 2,000 North America Supercharger locations (1,966 locations as of April 2023) and the ability to charge at DC Fast Charge stations such as Electrify America using the Tesla CCS Combo 1 adapter charging to 100% is mostly OBE.

I wouldn’t do it regularly....but road trips are so infrequent that it’s safe to charge to 100% and leave immediately

 

[Hiline]

Speaking of which, does charging to 100% give a significantly more accurate battery capacity estimate than charging to say 95%?

 

[jcanoe]

Speaking of which, does charging to 100% give a significantly more accurate battery capacity estimate than charging to say 95%?

Perhaps but only if you allow the Tesla Model Y battery management system to collect data at different state of charge levels from near ~100% down to ~20% or lower. Park the Tesla Model Y with Sentry mode, Smart Summon (if equipped with FSD) disabled so that the Tesla Model Y enters sleep mode where the battery management system can measure the open cell voltages (OCV) of the cells in the battery pack. (This automatic battery maintenance routine takes several hours each time it runs) and improves the accuracy of the estimated state of charge.