Because the last minute of range charge can last an hour, I've always thought that was when it was balancing the pack.
Because the last minute of range charge can last an hour, I've always thought that was when it was balancing the pack.
Doug_G
Lead Moderator
After a year and 21,000 km, I get a 90% standard charge at 350 km Rated, and a full 100% charge at 401 km Rated. (219 miles and 251 miles respectively.)
When the car was brand new I got 428 km Rated on a 100% charge. (268 miles.)
We know that the method of calculating the range has changed, so we can't say for sure that I've had a 6% decline. Also this chemistry reportedly has an early drop that levels out.
In comparison, my Roadster is down about 8% after 3.5 years and 35,000 km (22,000 miles). Different battery chemistry, of course.
When the car was brand new I got 428 km Rated on a 100% charge. (268 miles.)
We know that the method of calculating the range has changed, so we can't say for sure that I've had a 6% decline. Also this chemistry reportedly has an early drop that levels out.
In comparison, my Roadster is down about 8% after 3.5 years and 35,000 km (22,000 miles). Different battery chemistry, of course.
That is great to hear that too from others seeing their range "increase".
I do think there are a few varying factors to the "increase". One of course is "balancing". But the other is doing a full 100% depth of discharge cycle. This is nothing new, and I've stated it elsewhere as have many others, but just to reiterate here again after reading a few more things about Li-Ion battery chemistry. Basically, we should all know by now that doing the shallowest discharge/charge cycles is the best for the long-time health of out battery (aside from the obvious don't charge to 100% and leave it there especially in hot weather as well as the don't discharge to 0% of leave it there for weeks/months).
But lets say your daily charging routing is the following: charge to 70%, drive to work and have 55% remaining, charge back up to 70%, go home arriving at @55%, and charge back up to 70%. In this pattern, you're only doing two 15% depth if discharges daily. This is very good for the health of the battery. However, with Li-Ion battery chemistry, there is no cut-and-dry method of knowing what the exact charge state is. It's not like a gas tank where you can peer in and see how "full" it really is at 70%. I am omitting all the electrical details from here regarding voltages, temperatures, etc (because I admit I don't fully understand it all myself either). Basically there are methods of testing that will get you close, but it's not exact. The software can only do the best it can at "estimating" the state and range when you charge to 70%. Over time, this just gets a bit out of sync and the result of this is showing a "lower range" on our displays when that's not actually representative of the true charge state of the battery (also, this is applied to all cells, but I am described it as one big single cell). The only known reliable way of "resetting" this to be more accurate is to fully deplete the battery to 0%, and charging all the way to 100% again (which is NOT recommended to do daily, as described before the best daily pattern for long term heath of the battery is to minimize the depths of discharge). This accuracy is also assuming that the pack is fully balanced (which it won't be so this also isn't going to be 100% accurate to the battery degradation state either, but that is not what I'm trying to describe here).
So based on this knowledge, this is why it's not surprising to me to see someone get results like this - aka going on a road trip and doing several huge depths of discharge cycles and thus seeing their range increase at the end. IMO this is "expected" behavior, and I'm glad to see that it's working!
I'm a newcomer to this thread. Just thought I'd add my data point. Shortly after arriving home from a road trip in which my battery was deep cycled several times I did a range charge to 244 miles. I have an A battery pack with 22K miles.
Can we add a couple columns to the Battery Table wiki to log degradation? I'm very curious as to the A, B battery pack comparison as there are indications that B packs degrade more slowly in addition to supporting 120 kW SC.
Can we add a couple columns to the Battery Table wiki to log degradation? I'm very curious as to the A, B battery pack comparison as there are indications that B packs degrade more slowly in addition to supporting 120 kW SC.
Kraken
Member
From my experience it would appear that the range calculation on a full range charge had not really changed as of version 4.5 firmware. I had my battery pack replaced at around 23,000 miles and saw my 100% charge range return to 266 miles from the 250 I was getting on my old pack.
As a (limited) 40k owner, thought I'd add my stats. Received in June'13; consistently max charged to 140m daily. Updates in November appeared to reduce this to 128m daily.
How many miles do you get on a range charge and how many miles on the odo? Someone with a B pack was getting > 255 rated miles with 33 K. Seems far better than my 244 rated miles at 22 K.
The range calc changed in 5.x so it makes sense that you wouldn't have noticed the difference on 4.5.
qwk
P130DL
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There was a change in 4.5(.61).
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It's no secret that cars have different "rated mile" energy units(mine is 300), but has anybody that had their pack replaced for whatever reason noted the before and after "rated mile" number to see if it changed with the battery swap? I have a feeling that this number might be different depending on what the pack tolerances are.
dennis
P85D
I also have an A pack, and range charge now is 247 miles with 9500 miles on the odometer. Less than 10 range charges, less than 5 deep discharges, typical charge is <40%->80%.
Kraken
Member
While on 5.8, I had a main pack failure in late November. The night before the failure, I had done a range charge which stopped at about 248 miles (~18000 miles) and on the day after the main battery pack was replaced as well as on subsequent range charges, I have seen 266-269 rated mile range. When I first took delivery of the car, my range charge was to about 267 miles (on older versions of the software).
So I saw my range charge decrease from 267 to 248 over the course of the first 18000 miles and then back up to 266-269 immediately after replacement with a new battery pack.
ecarfan
Well-Known Member
I have only had my S85 a bit more than two weeks and have less than 1K miles on the odometer. I have never charged it to more than the 95% level (as indicated by the charging bar shown in my iPhone app) and that got me to 254 miles, so extrapolating I assume a 100% charge would be about 267. I routinely charge to 90% and get around 230 miles.
qwk
P130DL
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That could very well have been a case of an out of balance pack, especially if you don't charge to at least 90% every couple of days.
I was talking about the "rated mile energy unit" that rated miles are based off of, which is different for most cars. The "rated mile energy unit" line is displayed in the energy graph as a solid rated mile line.
AmpedUP
EV Nut
Can you explain what you mean by pack imbalance? IIRC, Model S initiates a pack balancing program upon charge completion regardless of SOC. What does 90% have to do with it?
I understand the fundamental concept of pack balancing, but I just don't understand what it is about 90% in particular.
qwk
P130DL
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How do you know this? I can only speak from my experience, but my pack gets out of balance when the slider is below 90%.
efusco
Moderator - Model S & X forums
All I could find was this, but it applies to the Roadster:
FW 4.5 got rid of standard mode, but I guess that could be where you are coming from. In my mind, it shouldn't matter whether it's set to 50% or 90%, the BMS should still balance the pack after a charge session has completed. Plus, there is no indication from Tesla to charge up to a certain percentage. They merely say to charge up to whatever you need, while minimizing range charges.
FW 4.5 got rid of standard mode, but I guess that could be where you are coming from. In my mind, it shouldn't matter whether it's set to 50% or 90%, the BMS should still balance the pack after a charge session has completed. Plus, there is no indication from Tesla to charge up to a certain percentage. They merely say to charge up to whatever you need, while minimizing range charges.
oh. I see. I just checked and the "rated mile energy unit" is 300 on the car now. It was definitely 308 before the battery failure while on previous OS versions, however, I don't remember looking at this unit in the days after it was upgraded to 5.8 but before the main battery pack failure. I'm going to claim ignorance but did this unit not change with the upgrade to 5.8 for all cars?
It's entirely possible that the pack was not balanced. I certainly didn't do anything special to try to balance it like deep discharges, etc.
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I wish I knew what triggered the failure.
The failure occurred suddenly while accelerating on streets. There was a loud boom and then the car warned me that it was shutting down and so I consequently pulled over into a parking lot. I originally thought it was a motor failure but this was quickly dispelled by the service advisor providing roadside assistance. He said that the system had flagged the main battery.
The car was towed to Costa Mesa service center and the main battery pack was replaced shortly thereafter.
As far as charging habits are concerned, I have never drained the battery pack into single digits. The lowest I ever went with that battery pack was 14 rated miles. I tend to charge irregularly, whenever needed, so there are some nights when I don't charge but some nights when the car is charged nightly. I also try to keep the average charge as low as possible based on what I've learned here in the forums. So bottomline, I don't think I'm different then an average owner.
I inquired a couple of times after as to what the exact cause of failure was and was told that the battery with be analyzed back at Fremont and that the incident was rare. I don't have any reason to doubt both statements but neither provides a clear answer.
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