100% first charge for break in?

[Thomas Edison]

I thought I read somewhere that for the first charge it’s a good idea to set it at 100% so the car learns it’s full capacity. Driving immedialty after so it doesn’t sit above 90%. Is this true? Also, is it a good idea to drive it down to 10% before that charge for the low end?

 

[TexasEV]

No to both.

 

[mongo]

I thought I read somewhere that for the first charge it’s a good idea to set it at 100% so the car learns it’s full capacity. Driving immedialty after so it doesn’t sit above 90%. Is this true? Also, is it a good idea to drive it down to 10% before that charge for the low end?

Agree with @TexasEV .
You're thinking of NiCd batteries, not Lithium Ion.

 

[AnarchyEOD]

30-70/80% is the sweet spot. Plug it in even if you don’t need to, and only charge to 100% if you’re immediately going to use those miles.

 

[FlyinLow]

One charge to above 95% every couple months to balance the pack.

Agree that average battery level should be 50%. For example, if your daily driving uses 60% of your battery capacity (miles doesn’t really matter, display % as units) then I’d charge to 80% nightly expecting to see 20% at the end of the day.

Setting the charge limit at 85-90% for the first week of your work commute will give you an idea of how many % you’re using on average.

I bump my car up to 90% on Friday night since I tend to do a lot of running around or driving for fun on the weekends.

Don’t forget to Enjoy!

 

[Eno Deb]

One charge to above 95% every couple months to balance the pack.

Is there any evidence that this does anything?

Below's a link to a post by Jerome Guillen of Tesla that's worth reading. Essentially what he is saying is that the range estimate shown on the display may decrease a little over time if you never charge to 100%, since it's based on an algorithmic estimate rather than an actual measurement. However, this is only the estimate, not the actual capacity. It's best for the battery to avoid fully charging (or discharging) and only charge up to 60-80% unless you need more range for a trip.

Tesla has the best BMS in the industry, and their engineering wizards clearly know what they are doing. No need for us peasants to manage the battery beyond these simple rules.

A Senior Tesla Executive's Comforting Answer to Concerns Re: "Loss of Range" | Tesla

 

[Trevor B]

One charge to above 95% every couple months to balance the pack.

Agree that average battery level should be 50%. For example, if your daily driving uses 60% of your battery capacity (miles doesn’t really matter, display % as units) then I’d charge to 80% nightly expecting to see 20% at the end of the day.

Setting the charge limit at 85-90% for the first week of your work commute will give you an idea of how many % you’re using on average.

I bump my car up to 90% on Friday night since I tend to do a lot of running around or driving for fun on the weekends.

Don’t forget to Enjoy!

that's not based on any facts, even remotely.

 

[TexasEV]

One charge to above 95% every couple months to balance the pack.

Agree that average battery level should be 50%. For example, if your daily driving uses 60% of your battery capacity (miles doesn’t really matter, display % as units) then I’d charge to 80% nightly expecting to see 20% at the end of the day.

Setting the charge limit at 85-90% for the first week of your work commute will give you an idea of how many % you’re using on average.

I bump my car up to 90% on Friday night since I tend to do a lot of running around or driving for fun on the weekends.

Don’t forget to Enjoy!

You’re treating yourself, not the battery. Years of experience with the Model S has shown you can just set it to 90% without any worries of how much or little you drive each day, and 100% for trips. Let the battery management system manage the battery and just enjoy your car. New owners shouldn’t think they have to obsess over the battery.

 

[mswlogo]

I charged to 100% on first charge (supercharger). It was half full and took like 20 min to get to 80%.
It was running at 100kw - 400 mi/hr.
It took a good 1.5 hrs to get to 100% (even though it said 20 min remaining).
It sat at 1kw charge rate and 310 miles range for a good 15 min before it stopped.
I think it even had a little extra kick when it was topped off like that.

I did it mostly to be sure it WOULD charge to 310 miles range and it did.
If it levels the batteries great, if it doesn't it won't hurt.

I think I will occasionally do the 100%. Problem is, I'd only do it on the highway stop and I don't really feel like waiting that long in that situation. We'll see. I wouldn't want to charge to 100% overnight.

 

[jsmay311]

Some Li-Ion battery packs only do cell balancing at the top of their SOC.

If anyone has any evidence that this is the case for Tesla battery packs, I'd love to see it. But I don't remember ever seeing anything to this effect.

 

[MorrisonHiker]

I think I will occasionally do the 100%. Problem is, I'd only do it on the highway stop and I don't really feel like waiting that long in that situation. We'll see. I wouldn't want to charge to 100% overnight.

If leaving on a trip in the morning, typically one would charge to 90% the night before. Then an hour or so before leaving in the morning, bump it up to 100%.

 

[mswlogo]

If leaving on a trip in the morning, typically one would charge to 90% the night before. Then an hour or so before leaving in the morning, bump it up to 100%.

That works. But I have a terrible time leaving when I plan too. If on a highway stop my options are more limited

 

[Jedi2155]

Is there any evidence that this does anything?

Below's a link to a post by Jerome Guillen of Tesla that's worth reading. Essentially what he is saying is that the range estimate shown on the display may decrease a little over time if you never charge to 100%, since it's based on an algorithmic estimate rather than an actual measurement. However, this is only the estimate, not the actual capacity. It's best for the battery to avoid fully charging (or discharging) and only charge up to 60-80% unless you need more range for a trip.

Tesla has the best BMS in the industry, and their engineering wizards clearly know what they are doing. No need for us peasants to manage the battery beyond these simple rules.

A Senior Tesla Executive's Comforting Answer to Concerns Re: "Loss of Range" | Tesla

It sounds like he's describing the exact issue you'd experience if you don't balance the pack occasionally. Pack balancing serves two purposes.

The first, the physical part, is to literally to balance the module capacities so they perform similarly. The big thing to point out is there is no physical capacity change of the modules, only where they currently sitting so that you maximize the possible output since a pack can only provide as much capacity as its lowest common denominator. Equalizing might bring some up, and some down. See this person's experience.

The second, software part, is so that software knows where the top and bottoms of the pack are and its hard to determine that without reaching 100% and 0% to set those limits. Doing it occasionally (once in 3 months or once in 6 months) is not a big deal and won't harm your pack unless you leave it sitting at 100%, but it does help improve the accuracy "advanced" of the software.

There is no need to do it at the beginning versus later. I only did it on my car to check to see if I have any bad modules (which I don't as it should be ).

 

[timk225]

Every month or two I run it down to 0 miles and charge it up to 100%. Got to stretch the battery or it gets lazy. Got to keep the BMS updated on its limits and balance the pack.

 

[Dana1]

The owners manual says 90%. The KISS principle seems applicable here. Charging slows down as battery approaches 100% because of heat.

 

[mongo]

The owners manual says 90%. The KISS principle seems applicable here. Charging slows down as battery approaches 100% because of heat.

Lithium charging is constant voltage constant current (limited voltage and current). Just like a capacitor, as the cells get closer to the maximum charging voltage, the charging current decreases (less net potential to drive the electrochemical reaction). You could start with a room temp pack at 95% and it would not charge any faster than one that started at 50% on it's way to 95%.

 

[Jedi2155]

The owners manual says 90%. The KISS principle seems applicable here. Charging slows down as battery approaches 100% because of heat.

The important thing that Jerome was emphasizing and what others have said is that, the car will take care of itself. If you want to be extra diligent, then you can and you will get a few extra %, otherwise don't worry about it.

 

[Eno Deb]

It sounds like he's describing the exact issue you'd experience if you don't balance the pack occasionally. Pack balancing serves two purposes.

No. He specifically says that this is a software issue related to the capacity estimation algorithm and that the true range is not affected. Battery balancing, on the other hand, is about making the full capacity of the pack available, which would impact the true range.

There is no need to do it at the beginning versus later. I only did it on my car to check to see if I have any bad modules (which I don't as it should be ).

As far as I know there is no evidence at all that exceeding a certain state of charge triggers some kind of special "battery balancing mode" in the Tesla BMS. At least I haven't been able to find anything but rumors. More likely the cells are being balanced all the time as part of the normal operation.

 

[Eno Deb]

Every month or two I run it down to 0 miles and charge it up to 100%. Got to stretch the battery or it gets lazy. Got to keep the BMS updated on its limits and balance the pack.

You are probably doing more harm that good (particularly with the deep discharge).

 

[AnarchyEOD]

What exactly are you breaking in?