My Tesla 3 SR is only 4 months old with 4000 miles. It’s range has dropped from 273 miles to 267 miles at 100% charge, that is 2% in 4 months time. Is this normal? Anyone experienced same issue?
LFP BATTERY Degradation
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Jeffyin
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I clearly am confused by your 'opinion'. Myself, I don't go by what Tesla recommends (charge nightly if you can) but with LFP batteries it is quite different that they NEED to be charged to 100%. Why would you still baby the battery by the 80-90% charging limit for non-road trips? Is there a study on LFP that supports your theory?
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dude: you wrote something 100% counter to what is known and what Tesla recommends. Exactly what did you expect?
btw, lurkers out number posters like 100 to 1 here; we DO read entire threads and all the posts. tsk, tsk for your assumptions.
But please do post something that supports your theory on LFP charging; I certainly missed THAT.
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perhaps you missed this "dude"
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Watch the YouTube video I linked. It does a good job of explaining why Tesla recommends charging LFP to 100%.
The short version is that the discharge curve for LFP batteries is quite shallow in the middle compared to NMC, making it very difficult for the BMS to estimate the state of charge. Charging to 100% puts the battery in a steeper part of the discharge curve, preventing the BMS from just making a guess.
It will be interesting to see how these LFP cars degrade over time, since most people will be charging them to 100% regularly per Tesla's recommendation. Hopefully they'll max out around 10% like Tesla's NMC batteries tend to do.
Aren't the standard range plus LFP and haven't they been out for a while already? I am getting a new Standard range. I have seen curves that indicate LFP degrades quickly then holds the range while NMC batteries degrade over time. The 100% argument is interesting. From what I have heard from Youtubers the LFP does not get hurt by charging to 100% or running down to 0% the same way NMC does. So charging to 100% makes no difference at all and just gives you less range anxiety.
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Not originally. They announced a plan to switch to LFP for standard range in October 2021. So they've been in North America for less than two years. There have now been a few complaints by owners that their one-year-old LFP vehicles have already degraded by 10%.
I suggest watching the video I linked earlier in this thread. It has more "meat" than the average YouTube video.
Watched the video and the information. If you want accurate range guesses charge to 100 at least once a week. If you want less battery degradation charge to 80% most of the time even though there is quicker degradation. In the end LFP will last longer overall. Clear as mud. Much like all things EV in these early days.
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I was resonding to the post that suggested that LFP should only be charged to 80-90%, which is contrary to Tesla suggests. I'd be curious for anybody who does baby an LFP, what happens over the life of the battery vs the charging to 100%. I think, tho, most LFP owners will follow what is suggested by the manufacturer and not a rando poster..
I have over 7,000 miles and lost only 1 mile when at 100%, and as you know by now, I don't go to 100% unless I will drive somewhere immediately to get it to at least 80-90%, and tend to keep it around 30-70% otherwise. The original poster who followed Tesla instructions and keeps his car at 100% lost 6 miles within 4,000 miles. Both cars are 4 months old. This doesn't have to mean much, since those are only 2 examples, but it's all I've got for now as "real" data, besides being a "rando poster". The youtube video from above (thanks garsh for posting it and reminding me that it came up in a different thread) is not the only piece of data. There is this article, but I think it shares the same sources as the video (sorry didn't rewatch the video lately), and there were also others, like this or this, discussing memory effect in LFP batteries, which are fortunately not permanent, but make BMS job difficult, because it introduces a systemic inaccuracy every time a partial charge happens. There are other articles, videos etc. but they can all be Googled, so I didn't feel the need to keep the list of them handy every time I mention that LFP=100% mantra may not be 100% (pun) correct. There are several discussions in this and other forums mentioning all the arguments from here, too. Usually the ONLY counter argument is "Tesla says so" (followed by the quote). They may be right, and all articles and vides are garbage, but more concerning is that when their sacred User Manual Quote gets questioned, they tend to get angry since they thought they won the argument by it and get disappointed. Well, you're on a forum - get used to arguing.
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BUT... we try to keep it a little friendlier on this forum.
Thanks for including the additional links in your post. It's difficult for people to accept that Tesla's charging suggestion for LFP batteries may not actually be the best approach to battery lifetime, so supporting evidence to the contrary is crucial to changing people's minds. It's important to understand this, and be patient in the face of the expected responses. Being friendly in the replies will make people more likely to listen to your evidence. People will naturally tend to ignore posts that are argumentative or dismissive, and that can be difficult to overcome.
My car is less than a week away from arriving, so I'm trying to gather best practice intel. The 80% rule is ok with me. The once a week at 100% is ok too. Just trying to pick the best plan as I plan several trips over the summer. In short I'm glad I joined and heard all this before I plugged it in every day to max charge. My current plan is 100% about every two weeks and a max of 80% the rest of the time.
I really try only to be informative and never to come out as unfriendly. I invite you to see my other messages and find any hint of being anything but respectful. This time I only noticed how the response to my message where someone would try to negate my argument by quoting the manual became just that, which means they didn't even read or take into account that whole post. And when they or someone else found themselves offended, I immediately apologized, to which they replied rather rudely calling me names. So I don't think it's fair to put all the blame on me, but I did learn long ago that people on forums are for some reason different than in real life.BUT... we try to keep it a little friendlier on this forum.
I really don't want this to become the discussion about forum etiquette, the topic is too important, so let's just talk about LFP batteries.
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....is that your take away from this thread? Can you at least acknowledge charging LFP battery vehicles is different from the (rest) of us with non-LFP batteries? I stand by my tagging the info posted that said to NOT charge to 100% as well as what Tesla recommends one does. As I posted would be interesting in a few years to get a real study of those who followed the recommendations and the few (or the one) who didn't in regards to LFP batteries.
btw, Elon also recommends charging nightly (via tweet) and that I clearly ignore. NO study on that either for short commutes.
In the end you do you and maybe know your opinion is just that. 🤷♂️
Of course I acknowledge LFP are different. My point is not that LFP = NLC, but that there is little evidence that keeping LFP at 100% is not harmful, let alone good for the battery, which seems to be how most people interpret Tesla's recommendations. The section in the User Manual (along with this note) is without sources or reasoning and it actually admits that charging to 100% is for keeping the BMS accurate, not to keep battery healthy. My opinion, on the other hand, is a a result of research, however flawed it may be. Even without those sources, it does make intuitive sense that keeping the battery at the highest possible voltage, far above nominal, is not making any Lithium-Ion battery happy. So it is not just an opinion. I have good reasons for it and I can back them up.
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thank you. Now we can agree to disagree and move on. well, as long as you don't post recommending LFP not be charged to 100% daily, or weekly as suggested.
We could agree, but unfortunately I don't, since you didn't provide any argument or reasoning to back you up. LFP being different is a fact, but it's not different in a sense that it means it should be charged to 100% daily or weekly. In fact, the research me and others quoted, along with common logic, suggests that it should only be charged fully to recalibrate BMS when it's convenient or needed, and then discharged to an acceptable level as soon as possible.
Here is a bit from a website We all know that to keep a lithium ion battery healthy, it should not be charged to 100% every day. At Recurrent, we suggest charging to 80-85% for optimal lifetime. However, this wisdom applies to NCA and NMC chemistry. Since LFP batteries are more stable, they can be charged to 100% for daily driving.
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LFP Battery In Your Next EV? Tesla and Others Say Yes.
If you read EV news or have thought about getting a Tesla this year, you’ve come across the letters “L,” “F,” and “P.” As in LFP battery.
www.recurrentauto.com
Good quote, something to argue with from the other side of the aisle, finallyHere is a bit from a website We all know that to keep a lithium ion battery healthy, it should not be charged to 100% every day. At Recurrent, we suggest charging to 80-85% for optimal lifetime. However, this wisdom applies to NCA and NMC chemistry. Since LFP batteries are more stable, they can be charged to 100% for daily driving.
.LFP Battery In Your Next EV? Tesla and Others Say Yes.
If you read EV news or have thought about getting a Tesla this year, you’ve come across the letters “L,” “F,” and “P.” As in LFP battery.
Well, the assertion in that article is that LFP batteries are more stable than their NMC counterparts at higher voltage. This may very well be true (although there are countering articles which can be found by googling "lfp battery degradation"), and it actually makes good sense since the nominal voltage is lower. However, the main point I am trying to make the whole time is not that we should not ever charge to 100%, it is that you should not want to have it as your goal to charge and keep it to 100%. Some people are taking the recommendation to charge to 100% as "100% is best for LFP", and they should reconsider.
I am going to error on the side of caution and charge to 80 most of the time. Gives room for regen, though I live on flat land and there is not much of that except for stop signs, stop lights and traffic jams. By the way anyone have charging curves for LFP posted here?
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Well, I guess if one doesn't consider the established facts, I didn't back up my opinion. The fact you are discounting completely is the recommendation from Tesla that LFP batteries need to be charged to 100% at least once a week and if an owner does it every night, that is fine too.
So it is kinda on you to provide a study, or something that demonstrates LFP batteries should be charged like all vehicle batteries to maybe 80-90% and only 100% for road trips. Right?
We await.
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