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Charge SR to 100% every time?

dmark1021

Member
Mar 7, 2019
54
20
Maryland, US
I was wondering how much % I should charge my SR.
It is downgraded from SR+, so 100% in SR now is actually just about 90% to the original.
Will charging 100% in this SR every time be ok?
 

zackmd1

Member
Sep 18, 2019
67
43
Maryland
I usually charge my SR to 90% because my normal commute only uses about 30% battery but charging to 100% is not a concern at all. If you need the extra range, 100% is not an issue, otherwise 90% is a good number.
 

BOBEDIGITL

Member
Apr 8, 2016
368
192
Los Angeles
A SR is technically a software locked SR+ so charging to 100% shouldn't be an issue in the long wrong. You're gonna get a lot of conflicting reports an opinions though. A good rule of thumb, just charge to 90% unless you absolutely need the remaining 10%, in that case, charge to 100.
 

BZM3

Member
Aug 15, 2019
281
183
Somewhere
I was wondering how much % I should charge my SR.
It is downgraded from SR+, so 100% in SR now is actually just about 90% to the original.
Will charging 100% in this SR every time be ok?
if you charge at home every night, and don't commute across state lines every single day, no need to charge that high. Charge to 80 and only to 100 when taking a long trip.
 

super20g

Member
Jun 28, 2018
911
623
United States
I was wondering how much % I should charge my SR.
It is downgraded from SR+, so 100% in SR now is actually just about 90% to the original.
Will charging 100% in this SR every time be ok?
I charge to 100% nightly on my SR. It is supposed to be top locked which would mean that is fine to do and would be like charing it to 90% ish based on the batteries actual capacity. There have been plenty of times we had a decent amount of stuff to do or went to a park a little ways away and were close on available range. I just keep it charged to 100% in case we need the range.
 

earthwormjim

Member
Jun 25, 2019
180
191
California
How do you know it's not "bottom locked"?

Previously posted comments by SR owners who charge to 100% state, that regenerative braking is not limited at 100%, like it normally is for all non software-locked models. This heavily implies the SR is top locked, and not bottom locked.

Bottom locking might also interfere with the BMS re-calibrating or re-balancing the batteries, which requires low charge levels to work.

There's also an interesting paper posted in the battery/charging section of the forum, which states that low charge levels are necessary to self heal cracks that form when nickel cathodes are under strain from being charged to high levels. This applies to high nickel content (above 0.8 ratio) cathodes, which the Model 3 probably does use.
 

dmark1021

Member
Mar 7, 2019
54
20
Maryland, US
I charge to 100% nightly on my SR. It is supposed to be top locked which would mean that is fine to do and would be like charing it to 90% ish based on the batteries actual capacity. There have been plenty of times we had a decent amount of stuff to do or went to a park a little ways away and were close on available range. I just keep it charged to 100% in case we need the range.

I am charging 100% right now, every time but not charging every day.
One of my major concern is that just in case the battery goes bad, within the warranty, would Tesla refuse to replace/repair because I charge 100% every time? Even though it is an SR downgraded from SR+?
 

mswlogo

Well-Known Member
Aug 27, 2018
6,193
5,340
MA, NH
Previously posted comments by SR owners who charge to 100% state, that regenerative braking is not limited at 100%, like it normally is for all non software-locked models. This heavily implies the SR is top locked, and not bottom locked.

Bottom locking might also interfere with the BMS re-calibrating or re-balancing the batteries, which requires low charge levels to work.

Good point.

But I would think bottom locking would be better for BMS re-balancing. It appears to do the heavy duty re-balancing when it gets to the top of a true full battery.

What it should probably do is "stagger" the usable window ;)
 

mba83

Member
Jan 10, 2019
117
53
South Carolina
There is got to be a way to get cell voltage read outs from the car in some debug mode or something? And compare values to a non-locked model 3, both charged to 100%.
 

ecarfan

Well-Known Member
Sep 21, 2013
19,418
14,432
West Vancouver, British Columbia
There is got to be a way to get cell voltage read outs from the car in some debug mode or something?
Yes, Tesla Service has access to that sort of information but Tesla owners do not. Which makes sense from Tesla’s point of view: they don’t want to deal with obsessive owners pestering them with questions about the exact state of charge of individual cells or groups of cells.
 
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earthwormjim

Member
Jun 25, 2019
180
191
California
apart from mswlogo noone here really gets the OPs question.

You should read the replies more carefully.

Yes, Tesla Service has access to that sort of information but Tesla owners do not. Which makes sense from Tesla’s point of view: they don’t want to deal with obsessive owners pestering them with questions about the exact state of charge of individual cells or groups of cells.

That's just a hostile consumer outlook. That's how anti right to repair laws get passed.
 
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Reactions: Common_Loon

OCR1

Active Member
Jan 28, 2018
3,765
4,280
Southern California
I’ve always wondered whether Tesla intentionally refuses to disclose how the battery lock in the SR works or whether they just don’t have anyone in charge of communicating these things. Just like the question of whether the motor in a Performance car is different than a non-Performance. Does Tesla really want to keep these things secret or are they just really bad at communicating?
 

SlimJim

Member
Jul 25, 2019
927
921
USA
Previously posted comments by SR owners who charge to 100% state, that regenerative braking is not limited at 100%, like it normally is for all non software-locked models. This heavily implies the SR is top locked, and not bottom locked.

Bottom locking might also interfere with the BMS re-calibrating or re-balancing the batteries, which requires low charge levels to work.

There's also an interesting paper posted in the battery/charging section of the forum, which states that low charge levels are necessary to self heal cracks that form when nickel cathodes are under strain from being charged to high levels. This applies to high nickel content (above 0.8 ratio) cathodes, which the Model 3 probably does use.
I will test this tomorrow morning.
I will charge to 100% tonight and see if regen brake works tomorrow.
 

ucmndd

Well-Known Member
Mar 10, 2016
7,047
13,839
California
Yes you can charge to 100%, every time, with impunity.

Yes, we know for certain the battery is top locked. There’s a thread documenting/confirming as much in the battery/charging section - if you want to try and find it by sifting through all the mindless droning on and countless duplicate threads about battery degradation, be my guest.

Yes, you’ll find lots of opinions on this subject. Most of them are bullshit and introduce false fears and claims that known things are unknown.

Charge to 100% all you want, it’s exactly the same as charging your physical battery to ~92%.
 

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