Full Charge

[Jerryt175]

I am a new owner of the Model 3 with the extended battery. What's the deal with not charging the battery to the fullest? The dealer said "we recommend taking the charge point down to about 75%" and I replied that I take long trips for work. With that input they said "oh then change it to the max charging". My question is what's the logic behind this battery level charge control?

 

[SigNC]

charging it to 100% routinely will impact battery capacity in the long run. If you are routinely driving long distances just charge to 90% or up to 100% if you are leaving soon and really need that extra 10%. What you don't want to do is charge it to a 100% often or charge to 100% and leave it sitting.

 

[DOCAL]

All lithium ion batteries degrade over time, even extremely well managed ones like in a Tesla.
One of the things that affects how quickly they degrade, is their charge state.

Charging to 90% puts less stress on the battery than charging to 100%.
Charging to 100% and then immediately driving the car puts less stress than charging to 100% and leaving it sitting.

The general recommendation seems to be that for daily use, charge up to 80 or 90%. When you're going on a trip, if you need the extra range, charge it to 100% shortly before you depart.

Don't be afraid of using 100%, just don't charge it to 100% every day and leave it sitting there.

 

[seattlite2004]

How does charging to 100% affect regen?

 

[ck867]

How does charging to 100% affect regen?

Regen doesn't work at 100%.

 

[seattlite2004]

Regen doesn't work at 100%.

Another reason why not to charge to 100% then...

 

[Krazaak]

Depending on the length of trip, you might be tempted to plot a route where you skip every other supercharger, but that can actually increase the trip time rather than decreasing. Due to the charge taper, you're better off charging to 60% at a supercharger to reach the next one than you are charging to 100% so you can skip over one. Basically it takes as long to charge from 0-80% as it does to charge from 80-100%.

I will often charge to 100% at home though if it means I can skip the 1st supercharger in a trip, since time spent charging at home is essentially free.

I was charging to 100% so I could go to a meeting in another city with a supercharger and return home without needing to charge, but I decided to change how I handled that. Since I often needed to leave a traffic buffer since I didn't want to be late for a meeting, I've started leaving early enough to spend 15 minutes charging before my meeting if traffic permits and if not I'll charge 15 minutes afterwards to make the trip home. I have free supercharging on the X though, so your experience might be different.

 

[Rocky_H]

Depending on the length of trip, you might be tempted to plot a route where you skip every other supercharger, but that can actually increase the trip time rather than decreasing. Due to the charge taper, you're better off charging to 60% at a supercharger to reach the next one than you are charging to 100% so you can skip over one. Basically it takes as long to charge from 0-80% as it does to charge from 80-100%.

I will often charge to 100% at home though if it means I can skip the 1st supercharger in a trip, since time spent charging at home is essentially free.

I was charging to 100% so I could go to a meeting in another city with a supercharger and return home without needing to charge, but I decided to change how I handled that. Since I often needed to leave a traffic buffer since I didn't want to be late for a meeting, I've started leaving early enough to spend 15 minutes charging before my meeting if traffic permits and if not I'll charge 15 minutes afterwards to make the trip home. I have free supercharging on the X though, so your experience might be different.

And I think there's a good personal/psychological point to that too. There's like a ramping/exponential kind of factor of how long it takes people to run out of things to do and get bored. 15 or 20 minutes is unlikely to make you bored, because you are doing about one or two small things that can easily use up that time without you feeling like you are waiting. You go use the bathroom and browse Facebook or email for a bit and 15 minutes disappears like nothing. But if you get into 40 and 50 minute charge times to go to a higher state of charge, you have to get more intentional about finding more things to do, or else it does start to feel more inconvenient, like you're waiting for the car.

 

[Dana1]

I am a new owner of the Model 3 with the extended battery. What's the deal with not charging the battery to the fullest? The dealer said "we recommend taking the charge point down to about 75%" and I replied that I take long trips for work. With that input they said "oh then change it to the max charging". My question is what's the logic behind this battery level charge control?

When battery charge is low, or close to full, charging generates heat which isn’t good on an everyday basis. This is why (I recently learned) the superchargers adjust amperage lower. 20%-80% you’re charging like a rocket ship.

 

[ratsbew]

I've taken it a step further and limit my charge to 60% for daily use. I only drive about 40 miles a day so this works perfectly for me and keeps the car out of both high and low SOC. Time will tell how this strategy works!