LR RWD not getting 325 mile range anymore

pdp1

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I charge my LR RWD to 80% (sometimes 90%) just about everyday and like others, I've noticed recently that the battery meter estimated range at isn't as high as it used to be. At 80% I get 248mi now vs 260mi previously and at 90% I get 278mi vs 292mi previously. Overall, I'm not terribly concerned about this as when I bring up the energy graph while driving, it estimates much more range than the battery meter, which is more in line as to what it always has been in the 9 months I've owned the car.

I'm bringing this up because this alleged decrease in range started happening after my first "longish" road trip which tallied just over 1000mi, where the weather was hotter than usual, 90F - 105F the majority of the trip. Also, while I occasionally supercharged in the past, this was the first time I (almost) exclusively used superchargers for 5 days straight. I'm wondering if the trip could have anything to do with the decrease in range estimates, or if it's purely because of a recent software update.
 

tivoboy

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I just forgot to unplug earlier and let it charge.. still topping out at 323 for me on LR model 3, with latest public SW.. I think it's 32.11. So, with 8K miles and good battery management, seems the software hasn't adjusted DOWN any of the at least on screen reported total MILES
 

sduck

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That's great for you, but there are plenty of people who this isn't the case for, if you read this thread through. This thread is for those who haven't had your luck.
 

Scubastevo80

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The discharge to 20% and go to 100% hasn’t worked for me. Stats and the car still peg me in the 296-298 range, even when averaging about 225 wh/mi over the past 6 months. Frustrating...
 

TeslaKiller

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The discharge to 20% and go to 100% hasn’t worked for me. Stats and the car still peg me in the 296-298 range, even when averaging about 225 wh/mi over the past 6 months. Frustrating...
As far as I heard, to really rebalance the BMS (not the battery cell chemistry) you have to go below 10% to nearly 0% and stay there and go to 100% and stay there for a while.

But this might get the BMS calibrated, but the battery will suffer.

So unless you have access to the BMS via CAN Bus you don't really know if Tesla just changed some voltage calculations with the firmware or if you have a battery degradation or if it is a BMS calibration issue.

Maybe if you politely talk to a more experienced technician down at Tesla and ask them to rebalance or reset the BMS, that might help it. But I know that a lot of those guys are not that experienced so you will have to luck out.

Also, another thing to understand is that the rated miles you are seeing on your RWD are for the full capacity, including the buffer (think of reserve in the gas car). This is how Tesla and EPA calculates it. But to actually get to the reserve, you need to go below 0%, because Tesla is using "usable" capacity (without buffer) from 0-100%. In order to reach 325miles on a fresh battery therefore you have to drive at 96% rated consumption in your energy graph inside the car.

So the 298miles you averaged while driving 225Wh/miles might be pretty spot on - what does the car say when you are at 100% in KMs or Miles (KMs is more accurate in measurement)?
 

garsh

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...this might get the BMS calibrated, but the battery will suffer.
I just wanted to highlight this part.

No, it shouldn't hurt the battery much at all if you only do it once and not for too long. But this is why I generally don't think it's worth worrying too much about calibrating the BMS unless you're seeing more than 10% degradation. The "low-charge, full-charge" calibration procedure often doesn't seem to make much difference, and it's quite possible that Tesla will push better BMS software in the future that will solve any BMS issues. Unless you're pushing your car's range limits, it's not worth the hassle.
 

TeslaKiller

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Exactly, unless you go from 100% to 5%, you wouldn't need to worry about the BMS as there is enough buffer + rest %.

But having said that, I did need to drive 280 miles on two occassions on a one go without charging, so having a nice balanced BMS is a huge bonus.

As for the battery, neither you nor me knows what it will do to the battery if we charge it to 0% and have it sit there for a while - it might not hurt it from one calibration, but you also might trick some voltage disbalance in a cell. I have too little of experience with li-ion batteries and only perpetuate what smarter people with more experience like Jack Rickard explain.

So yeah, I would definetely not want to recalibrate the BMS like that. And if nothing like this helps, I hear Tesla can trickle a BMS reset via software on the car (not quite sure how or if they do it) and maybe that will help.
 

pdp1

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I finally charged to 100% for the first time this past weekend since I got my Model 3 in Dec 2018. It only got to 303miles out of 325miles. While it's really annoying, I noticed if I go to the Energy graph while driving, in most cases it still estimates that I'll get 325miles (or more) when I use the last 15 or 30 mile graph. I'm a little tempted to try the discharge/charge thing to calibrate the BMS, but unless I have a longer 100+ mile trip to make in the near future, I'm going to skip it and just let the decreased range estimate bug me a little when I get into my car first thing in the morning after a night's charge.
 

TeslaKiller

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Unless you intend on driving 280 miles on 1 go you shouldn't bother. 100-150miles you have olenty of space. Maybe you can speak to Tesla and see if this is normal degradation or your BMS is uncalibrated and if they can reset it manually.
 

pdp1

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I charged to 100% for the fi
I just wanted to highlight this part.

No, it shouldn't hurt the battery much at all if you only do it once and not for too long. But this is why I generally don't think it's worth worrying too much about calibrating the BMS unless you're seeing more than 10% degradation. The "low-charge, full-charge" calibration procedure often doesn't seem to make much difference, and it's quite possible that Tesla will push better BMS software in the future that will solve any BMS issues. Unless you're pushing your car's range limits, it's not worth the hassle.
While it's just a nuisance now and I'm pretty confident my battery is ok as it's still less than a year old, I'm afraid if this persists, it may mask any real battery degradation issues as my battery gets older. I hope Tesla fixes this sooner than later.