Should I charge M3 every night or wait until 60% or else?
I have a brand new M3 from Dec 21, 2020. The sales girl told me I should only charge my car when it is down to 60%. I work at home and only drive to shopping. So every couple days my battery down to 60%. But on a YouTube video, somebody said you should charge your M3 every night. It does lose 2-4% at night without charging. So who is right for thennew battery of M3 for its best capacity?
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Rinse, repeat.
If I were in your shoes, I’d set the charge limit to 80%, and plug it in whenever I felt like it - every night would be good, waiting took it drops to 60% Is good, waiting till it drops to 30% is good. The battery is gonna last 300,000 miles no matter which of those you do.
Don’t overthink it. The three rules are:
1. Don’t charge to 100% all the time. It’s fine for long trips, but not daily charging. 80 or 90% for daily charging makes the battery smile.
2. Charge before it gets too low (10 or 20%) because it really sucks in an EV to run out of charge.
3. The car is perfectly happy to be left plugged in all the time, so that’s a good way to keep it.
And just keep grinning.
Set max charge to 70% and then charge it when it reaches 30% (if that meets your driving needs). When I leave my car my garage when I go on vacation, I charge it to 60% (my garage stays warm as I live in So Cal). I do not leave it plugged in all the time. I charge it 1-2 times per week. Long range RWD M3
Telsa's battery management system (BMS) likes to see a 90% or greater state of charge once in awhile so it can properly calibrate the pack. Check out this YouTube video by Kim Java to learn "How Tesla Wants You to Charge Your Car in 2020": https://youtu.be/MrwmNKtnh84
The simple truth is that, NMC batteries indeed feel well around the 50% mark. Charging them slowly to 60% and keeping them there will make them last almost forever.
However, even daily charging to 80% still keeps them happy for many years, and the occasional charging to 100% doesn't destroy them instantly.
So the simple rule is, set the charger to what you expect to need the next day, but not below 60%. Connect the charger to the car whenever you can.
And it cannot hurt to read the manual. It has a few useful things to say about charging.
There are a few qualifications. One is that at temperatures well below freezing you can save money by doing longer charging sessions, because the extra energy to warm up the battery is needed only once per charging session. If your electricity is cheap, it may not matter much though.
Another is that, if you have a new Made in China SR+, it has an LFP battery, to which different rules apply. In short, these batteries are more resilient, but not as easy to measure. The recommendation is to charge these up to 100% about once a week to help the BMS calibrate. They don't suffer from this as much as NMC batteries do.
It is true that Li-Ion batteries will last the longest if kept at 50% and then never used, but then you aren't using the car so you obviously can't do that.
Leaving the battery at 100% is bad so you shouldn't do that. Draing the battery to actual 0% isn't the best either and if it stays at 0% for too long you can actually kill it.
Tesla says charge to 90% but that is more PR I think.
Lots of people try not to even go down to 10%, and 20% low is normally said as well.
But you have to use the car the way you need to, so charge it accordingly. If 70% is plenty for the day and you won't be below 20% or 10% at the end of the day then do that.
And for my personal opinion...I charge to 70% or 75% and won't plug in till I am down to 30% or so.
> It is astounding how much false information is spread around this topic. Fortunately, the Tesla Battery Management System automatically prevents the worst mistreatments of the battery.
>
> The simple truth is that, NMC batteries indeed feel well around the 50% mark. Charging them slowly to 60% and keeping them there will make them last almost forever.
>
> However, even daily charging to 80% still keeps them happy for many years, and the occasional charging to 100% doesn't destroy them instantly.
>
> So the simple rule is, set the charger to what you expect to need the next day, but not below 60%. Connect the charger to the car whenever you can.
>
> And it cannot hurt to read the manual. It has a few useful things to say about charging.
>
> There are a few qualifications. One is that at temperatures well below freezing you can save money by doing longer charging sessions, because the extra energy to warm up the battery is needed only once per charging session. If your electricity is cheap, it may not matter much though.
>
> Another is that, if you have a new Made in China SR+, it has an LFP battery, to which different rules apply. In short, these batteries are more resilient, but not as easy to measure. The recommendation is to charge these up to 100% about once a week to help the BMS calibrate. They don't suffer from this as much as NMC batteries do.
You stated a slow charge is better for the battery than a fast charge. I have been charging with 240V but could easily charge with 120V and get the range that I needed for next day. Is this what you are recommending?
240v is not considered fast charging and should be fine for your battery
After reading this thread, I might let the charge drop to maybe 40%, so 60% is the average, which apparently is the sweet spot for our batteries. Does that sound good? :wink: My car is a 2021, and don't know if it has an LG or Panasonic battery, but nothing should have changed from 2020 and prior. I'm currently in a long trip, where I needed to charge to 90% a couple of times, and dropping between 20 to 30%. Didn't want to risk running low, due to high (head) winds, missing an exit, etc. I feel pretty good doing that, having a good safety net. And that is not really slowing us down, since car is done when we're ready to leave. We weren't used to stops, hardly stopping, but at almost 60, this more relaxed way was nice, even when it added almost like an hour to our typical timing. Enjoying the new Teslita :).
1. I live in South Florida and don't drive everyday. Occaional supermarket and outings don't use lots of battery. Is it better to set the max at 60% since the battery likes around 50% full?
2. How do I find out if my battery is the one made in China?
3. Since I don't drive it often, and each trip doesn't use much battery, should I still keep it plugged everyday in the garage?
4. Or only keep it plugged after every drive?
60%, 70%, 80% are likely identical as far as the battery is concerned. It’ll be perfectly happy with any of those, and last 300,000 miles.
I don’t think any made-in-China batteries have been imported to the USA, so don’t worry about it.
In your circumstances, the car won’t care whether you leave it plugged in all the time, plug it in every other day, or plug it in once a week. Your usage is so light that you battery is gonna last forever.
> You stated a slow charge is better for the battery than a fast charge. I have been charging with 240V but could easily charge with 120V and get the range that I needed for next day. Is this what you are recommending?
Any AC charging counts as slow, particularly single-phase AC with less than 4 kW. 11 kW, even 22 kW (3-phase AC) is still slow. So no worries. 50 kW and higher counts as fast charging.
In fact, 120 V single phase is extremely slow and may not even work in a very cold winter phase, because it does not provide enough power to warm up the battery for charging.
The reason why slow charging is better for the battery is that it is actually the cell voltage that counts. Li-ion Batteries don't like high voltages. And so a combination of less than full charging and slow charging provides the best environment for the battery.
But still, charge fast and high if you need it. I keep reminding everybody that we are not servants of the battery. The battery is there to serve us. So, if you go on a long trip and have a long distance to cover to the next fast charger, do charge up to 100% at home. As long as you don't do that very often, a Tesla battery will not suffer unduly.
That leaves it at 100% for the shortest time and will be warm when you leave for best range.
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> After reading this thread, I might let the charge drop to maybe 40%, so 60% is the average, which apparently is the sweet spot for our batteries. Does that sound good? :wink:
It sounds as the same flawed logic as this thread is already filled with.
It is quite correct that Li-Ion batteries are happy around 60%. The closer they get to the top and bottom, the shorter they will live.
But based on that, how do so many people reaThch the strange conclusion that they should discharge their batteries over several days insted of charging them daily?
Why charge to 80% and then use several days to discharge to 40%.
Why not for example charge to 65% every day and then discharge to 55%? This will keep the battery even closer to the optimum charge level all the time.
(I am not saying that you should overthink it like that. I am only saying that if you want to overthink it, at least overthink properly.)