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Charge at 100% once per week? [LFP RWD model 3]
- Thread starter TonyUsa
- Start date
You have a RWD which uses an LFP battery. It is indeed recommended to charge to 100% "regularly". The reason is so the BMS can get a proper estimate of battery capacity. Early on people were not doing it often and it led to people getting stranded because the indicator showed 5% left and the car stopped driving, something like that. Typically you can go under 0% and the car still drives, although that's not really recommended to do. LFP batteries have less voltage variation in the usable range so giving a 100% reading to the BMS helps it. LFP are also less damaged by charging them fully.
Huh, so on my 2021 build (non-LFP), is it best to just charge to 80%? I don't think we've ever charged the car to 100% because the sales guy said 100% can damage the battery.
Basically we treat the car like a 250 mile range EV lol.
You're not talking about the same thing.
LFP vs NCA
One is not like the other in charging usage.
Yes. Your NCA battery is better to not charge to 100% a lot. It doesn't mean you can't do it. Just charge it to 100% when you are going on a long road trip and just start driving soon after it charges to 100%. Don't let it sit at 100% for a day.
ATPMSD
Active Member
Why are you limiting your charge to 17a? Charging at 32a versus 17a has zero impact on battery life.
(moderator note)
I edited this thread title because its pretty clear that the OP of this thread is talking about a RWD model 3 with the LFP battery chemistry, which is NOT AT ALL the same as ANY LR or Performance Model 3 / Y/ S X.
The recommendation from tesla to charge that way on a LFP model 3 does not apply to ANY other tesla that is not equipped with that specific battery chemistry, and currently NONE are except that specific vehicle.
So, anyone reading this that does not have that specific vehicle should not be following that specific advice.
I edited this thread title because its pretty clear that the OP of this thread is talking about a RWD model 3 with the LFP battery chemistry, which is NOT AT ALL the same as ANY LR or Performance Model 3 / Y/ S X.
The recommendation from tesla to charge that way on a LFP model 3 does not apply to ANY other tesla that is not equipped with that specific battery chemistry, and currently NONE are except that specific vehicle.
So, anyone reading this that does not have that specific vehicle should not be following that specific advice.
The message very confused me as "We recommend keeping your charge limit at 100% and charging fully once per week".
From my understanding "We recommend keeping your charge limit at 100%" meaning the every charge should at 100%.
But why they added "and charging fully once per week". Now it meaning that only charge to 100% once per week.
So which would be better for the battery. I normally charge 3 times per week. First, charge at 90% 2 times per week and at 100% 1 time per week. Or Second, charge at 100% 3 times per week.
Thank you,
Although LFP is less affected by being at 100%, it's not immune to it. Best for the battery is to keep it lower around 50%. Best for the BMS is to see both voltage extremes to get the best estimate. But then again best for the battery is small, frequent charges instead of big quasi-full charges. You cannot have the best of everything. Even with NCA batteries it's good for the BMS to see the voltage extremes but detrimental for the battery.
Now, how detrimental are we talking about? It seems like it might just be ~3% degradation difference after 200k km, based on the stuff I've read around here. Don't worry too much about it.
EDIT: Forgot to say: best for the owner is to have a relatively full battery so you never run out of juice whatever the circumstance
Now, how detrimental are we talking about? It seems like it might just be ~3% degradation difference after 200k km, based on the stuff I've read around here. Don't worry too much about it.
EDIT: Forgot to say: best for the owner is to have a relatively full battery so you never run out of juice whatever the circumstance
From my understanding that the higher amp you charge will do the damage to the battery more that the less amp. Coming from RC hobby and we use lithium batteries also, the higher amp we charge the life of the battery will be shorter that the battery that charge with lower amp. So if I am not in the hurry I always charge at 17amp. But new technology change everyday, are you sure that will not impact on the battery life if I charge at 32 compare to 17 amp.
This proves that even in a situation where its perfectly fine for the person to charge to full every time they use the car, people will still worry about the battery.
The message they are trying to tell you is to both keep your charge limit at 100% and also try to ensure that at least once a week you actually hit that charge limit. There is absolutely, positively no reason for the CAR that you should be "charging 3 times a week, first to 90% two times per week and 100% 1 time per week".
it simply isnt necessary for a LFP model 3. You could charge it at 100% daily. What they dont want you to do is not charge it to 100% at least once a week (unlike every other model 3 battery type).
ATPMSD
Active Member
A measure of charging rate is C, which is the rate divided by battery size. Not sure of your battery size, but let’s assume it is 65 kWh. Charging at 17a is 17/65 = .26 while 32/65 =.49
Generally speaking, anything below C=1 has zero impact on the battery. Note that charging at 48a is just .74
Also, the higher the charge rate the more efficient, so slower is also a bit more expensive.
Thank you, sir. So they are the same as we calculate in RC lithium too as we always charge at 1C or below.
ATPMSD
Active Member
Yes but your car has an LFP battery, which is not the same chemistry, however as far as I know the same rule applies.
TheRealTVGuy
Member
I’m hoping someone can help a new-ish Model 3 owner. I purchased a used 2018 Model 3 “Mid Range” (single motor) a few months ago.
Should I charge to 100% every time?
Should I charge to 100% every time?
No problem, and sorry for the fairly extreme "dryness" of my previous response. 3-4 years of reading battery threads sometimes makes me respond more "sharply" than I intended.
No. That only applies to this specific RWD model 3 that has the LFP battery, late 2021 into 2022. No other model 3s.
