Long Trip - Supercharge to 100%?

[chezedog]

As I understand it you shoudn't charge the vehicle to 100% on a daily basis, but it's OK once in awhile, such as when traveling across the country. Is this correct, or should we keep it to 90% while traveling? Had it only 4 days.

 

[juliusa]

100% is fine when needed. That is what it is there for.

 

[jimmythefrack]

Supercharging to 100% is super inefficient. It'll take a long time after you hit 80% because of the taper while supercharging. Its a lot better to try and keep the car between 20 and 80% while jumping from supercharger to supercharger. You'll waste a lot of time charging all the way full when you don't need to. If you're going to charge at home, charge to 100% and then charge lower at each supercharger you hit.

 

[TexasEV]

Supercharging to 100% is super inefficient. It'll take a long time after you hit 80% because of the taper while supercharging. Its a lot better to try and keep the car between 20 and 80% while jumping from supercharger to supercharger. You'll waste a lot of time charging all the way full when you don't need to. If you're going to charge at home, charge to 100% and then charge lower at each supercharger you hit.

He wasn’t necessarily asking about supercharging. Of course you shouldn’t supercharge to 100% unless you really need the range. But when traveling across the country, staying at hotels with destination charging and starting each morning with a 100% charge is a great time saver. The point is if you’re waiting for the car, then only charge what you need for the next stop plus a margin, but if the car is waiting for you, then it should be charging.

 

[forkee]

Supercharging to 100% is super inefficient. It'll take a long time after you hit 80% because of the taper while supercharging. Its a lot better to try and keep the car between 20 and 80% while jumping from supercharger to supercharger. You'll waste a lot of time charging all the way full when you don't need to. If you're going to charge at home, charge to 100% and then charge lower at each supercharger you hit.

i've noticed that when i supercharge my 3, it really only slows down at 95%, then practically trickle charges the remaining amount. Like it will take an hour to get from 20% to about 95% and then another hour to get to 100%, so yea i also think it's a waste of time juicing it all the way. That extra 5% is only going to get you an extra 30 miles or so, so i would use it only if you need that little bit more. you can shave a good amount of hours off a trip if you supercharge hop for only 30-40 minutes at a time rather than a full hour.

i usually will get it to 95%, then when i get home it's right at 90%.

 

[Eno Deb]

i've noticed that when i supercharge my 3, it really only slows down at 95%, then practically trickle charges the remaining amount.

It starts tapering around 45% SoC (see e.g. here).

As mentioned above, when roadtripping using the superchargers, it's most efficient to only charge as much as necessary to get to the next charger. You want to arrive with a low SoC so you can charge a lot of energy quickly before the charge rate tapers off too much. That said, at least here in CA where the chargers tend to be crowded you often won't get the full rate anyway because you're sharing a charger with another car or the rate is limited for other reasons.

 

[ewoodrick]

Yes, charging to 100% for trips is definitely the correct way to go.

And for you other folks, If you follow the on-board nav recommendations, you don't ever charge to 100% at a Supercharger. But that doesn't mean that you don't charge to 100% on a trip.

At Superchargers, you generally should charge up to the point at which charging starts to taper, as long as the next charging location is in range, or to a lot higher (but probably not 100%) on the last hop into your destination, to give you room to drive around.
At the beginning of the trip, you probably should be charged to 100% and on any nightly stops with charging, you should possibly charge to 100%

If Tesla folks were to ever talk to the non-Tesla folks, you will find that most DC Fast Chargers tend to recommend or limit fast charging to 30-45 minutes and then move to a L2 (i.e. destination charger, often collocated) for the remaining topping to 100%, if desired.

 

[forkee]

It starts tapering around 45% SoC (see e.g. here).

As mentioned above, when roadtripping using the superchargers, it's most efficient to only charge as much as necessary to get to the next charger. You want to arrive with a low SoC so you can charge a lot of energy quickly before the charge rate tapers off too much. That said, at least here in CA where the charger tend to be crowded you often you won't get the full rate anyway because you're sharing a charger with another car or the rate is limited for other reasons.

well....yea but it's still going pretty fast up until about 50 minutes in. why not fill it up a little bit more while you're already plugged in just in case the next stop is unavailable or super crowded.

 

[Eno Deb]

well....yea but it's still going pretty fast up until about 50 minutes in. why not fill it up a little bit more while you're already plugged in just in case the next stop is unavailable or super crowded.

You'll see when you make your first long road trip. It's no fun to wait around longer than necessary.

To the original question: it's fine to charge to 100% occasionally. It's just that in CA with its high supercharger density it's rarely necessary or even useful.

 

[Big Earl]

In 6,000 miles, I've never fully charged the car to 100%. When traveling (most of those 6,000 miles), we run from about 12% state of charge to 60-70% state of charge. Rather than following the nav's suggestion of fewer stops for longer periods of time (often 40 to 50 minutes), we plan our stops so that we spend the most amount of time in the fastest part of the charging curve. On a 500 mile trip, we'll often stop to charge four times instead of the nav's recommended two, which in most situations results in a faster overall trip time.

I highly recommend using http://www.abetterrouteplanner.com for planning your trip in advance. You can adjust settings for temperature, head wind, travel speed and weather conditions to get a very accurate idea of how much energy you'll use and where you'll need to stop for the best average trip speed.