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Yea, B packs seem to be consistently and substantially better than A packs for similar miles and age.
I can hope A and B sort of converge over time, but as it looks today, A pack owners got noticeably inferior technology.
I know an A pack owner that has more miles than me, and his max rated range is 260. I baby my pack, he abuses it. The high rated range display(most lower numbers are not degradation) is attainable by keeping the pack balanced, and avoiding charging to less than 90% as much as one can. This of course will contribute to higher degradation than someone who keeps the slider at 50%, and ends up with a pack out of balance.
New cars have more closely matched cells within the modules for a better balance, and thus range display. This is evident by the number of highlighted cell groups that are at the same voltage levels in the first BMS screen picture, and the opposite is happening in the second picture. This is why we have such a difference in peoples displayed range numbers. Most cases have little to do with actual battery degradation. I tried to explain this in the beginning of this thread, but it fell on deaf ears.
The day will come when someone, or a group of someones, will sue Tesla over lack of disclosure about battery degradation. Look, there are a lot of ill informed people who buy these cars. I can bet more than a few of them have no idea that batteries degrade over time and will expect their range numbers to stay the same in 8 years. I'm just saying that it will happen at some point and Tesla should make it more clear that the car will lose some range over time. Right now, I can't find that information anywhere. I also don't remember Tesla telling me anything about battery degradation at the time I purchased my car. I just know that batteries degrade and that it's a facto of life. Someone else may not know that.
No doubt true. An exception doesn't invalidate a trend though. "A" pack owners are consistently, as a whole, reporting more degradation (or imbalance, if you prefer) that B packs. Perhaps the anecdotal evidence here isn't sufficient to establish a real trend though.
No, I heard you then. I contended then and still do now that it's mostly irrelevant if a pack is out of balance or degraded since I don't have access to those miles either way. There may be some mysterious way to balance, but I've ranged charged a handful of times and left the car for multiple hours to balance at the end and it's never made any difference. If I can't get the pack to balance, it has the same functional utility as a degraded pack.
Yea, B packs seem to be consistently and substantially better than A packs for similar miles and age.
I can hope A and B sort of converge over time, but as it looks today, A pack owners got noticeably inferior technology
I have a B pack with 15K miles and get about 224/254 charging.
Kipernicus
Model S Res#P1440
I'll caveat though that if it's truly imbalance then at least there's hope it could get better somewhere down the line via a software update or a specialized Service Center visit. Until then, there's no difference from the consumer perspective between degradation and imbalance.
Todd Burch
14-Year Member
Have you tried charging regularly to 90% (or I should say the top of the daily charge range) for a month or so? Most reports of improved range numbers seem to be a result of following that routine.
hans
P631
I have a similar situation to @ckessel and I have charged to 90% every night for months without getting my range back. This works for some people but not everyone, and not me.
I've charged to 90% every time I plug in since I got the car 20 months ago, with the exception of few week period where I tried 80% and decided that seemed pointless.
So, the short answer is Yes
Pilot_51
Member
What did you charge to before and how much range have you lost? The only way to completely balance the pack would be to charge to 100% or discharge to 0%, but since that increases degradation, 90% is recommended for partial balancing and may not actually show an improvement.
Let's try this thought experiment (I have no scientific basis, just a simplified guess): You get your car with 0% imbalance. As time goes on and you always charge to 90%, the imbalance gradually increases to a maximum of 20% (this assumes a constant 50% charge is where imbalance can be 100%). If you always charge to 80%, the maximum imbalance would be 40%. If you only charge to 80% long enough for the imbalance to reach 20% and then try balancing to 90%, there's a chance you won't see any improvement since the imbalance is not more than what you would naturally get with a 90% charge. Of course, it's more complicated than that given the BMS and the many cells, but this should give you a basic idea as to why I think you may not be seeing an improvement.
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I have my charge limit set to 90% (originally 92-93%). I charge nightly (except sometimes when travelling, or when I am rearranging cars, or at a service center or....) and am seeing 221 miles rated after 40k miles.
My recollection is that the prevailing theory is that balancing happens "above" 90% (at 99% or 100% has been debated somewhat).
To take this one step further, most cars will get back to like new range by charging to 100% and letting the car sit for a certain amount of time(weeks, months). I have seen this firsthand(not on my car), but this is a sure way to ACCELERATE real battery degredation. It's something that would be my last resort if I had lower range showing. Some Service Centers do this or used to do this to help rated range go back up. Tesla engineering says it's working on a solution to fix this problem, but from a technical point of view, it seems very difficult to address without resorting to the extreme measure I explained above.
FYI, Tesla freaks the F out if they find out someone has been messing around in the service menus. There are quite a few changes that could be made, so I really don't blame them.
FYI, Tesla freaks the F out if they find out someone has been messing around in the service menus. There are quite a few changes that could be made, so I really don't blame them.
I'm almost at 32k miles on my B pack and in range mode (AC setting) a full charge this morning got me 254 miles. Turning range mode off dropped the estimated range by a couple miles shortly after turning it off (without driving), so it's important to include that setting whenever you post your range.
mknox
Well-Known Member
I had been doing the 70% to 40% SOC daily for quite some time and also say my Rated miles drop. I've set the slider to 90% for about a week now (end the day at about 60%) and have seen 1 or 2 additional miles come back at the 90% mark.
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