What is supposed to happen when you hit 100% charge at supercharger?

[anon125110]

So I got MY yesterday. Went to a supercharger to test it out. Set limit all the way up, since Im testing. Car got up to 100% but continued trickling at 1Kw (I waited about 10 minutes and it kept like that). The time estimate was just "Calculating" for the entire 10 minutes. I ended up tapping "Stop Charge" in top right and stopping it myself. Curious if this is normal?

Charge up to 100% was as you would expect, started at 60kw or so, then slowed down as it approached 100%.

I have other EVs and those like display a message, or send update to the app etc that charge is complete. Does Tesla not do that? Is it different at supercharger vs home charging?

This is what it looked like: Imgur

 

[SSedan]

No problem, 100% takes a long time to actually hit.
Also sitting in the car keeping it on uses power.

 

[doghousePVD]

Sitting in the car with a/c or heat? Listening to radio? Charging cell phone?

The 1 kW figure means up to about 1 kW, not 1000 Watts exactly. The display will never read 0.1 kW.

I guess it can take an hour+ to get to 100.0% from 99%.

 

[Chippylad]

Sitting in the car with a/c or heat? Listening to radio? Charging cell phone?

The 1 kW figure means up to about 1 kW, not 1000 Watts exactly. The display will never read 0.1 kW.

I guess it can take an hour+ to get to 100.0% from 99%.

I also think that the “rounding error” due to showing the charge level to the nearest % is also a factor

 

[TomServo]

But shouldn't the car notify you via the app or text msg it's charging is done. My 2017 Volt sends me messages when charging is done or if it's been interrupted. is that something you need to set up in the Tesla app?

 

[jf64k]

But shouldn't the car notify you via the app or text msg it's charging is done. My 2017 Volt sends me messages when charging is done or if it's been interrupted. is that something you need to set up in the Tesla app?

Same with my 2017 Bolt...I charge to 100% 7 days a week and I get a text when it’s at 100%.

 

[drtimhill]

But shouldn't the car notify you via the app or text msg it's charging is done. My 2017 Volt sends me messages when charging is done or if it's been interrupted. is that something you need to set up in the Tesla app?

It will. In your case you didn't quite reach 100% (charging slows down as you get closer). Normally you will get notifications on your phone as the car nears charging complete, and when it is complete.

 

[leodoggie]

Li ion batteries top balance, therefore the bms is balancing all the cells to the same voltage. As there roughly 7000 individual cells this could take awhile. It is recommended to top balance every two to three months. This is a very rudimentary explanation, I am sure there are more experienced Tesla owners who could give you a more detailed explanation. Hope that helps.

 

[animorph]

Charging to 100% is unusual in itself. And it can take a long time. Normally, with a charge limit of 90% or less, it goes right to the limit fairly quickly. In all cases you should get an almost charged and a charge complete notification.

 

[Zoomit]

Car got up to 100% but continued trickling at 1Kw (I waited about 10 minutes and it kept like that). The time estimate was just "Calculating" for the entire 10 minutes. I ended up tapping "Stop Charge" in top right and stopping it myself. Curious if this is normal?

Yes, it is normal. Typically, it will hit 100% and still be charging at 2-3 kW, though I've seen as high as 7 kW. The charge time from when it first indicates 100% to when it indicates charge complete can be as "quick" as 10 minutes to an hour. The variation depends on battery temperature, brick balance, and BMS calibration error.

Also sitting in the car keeping it on uses power.

Sitting in the car with a/c or heat? Listening to radio? Charging cell phone?

The displayed charging power is different between AC Level 2 charging and Supercharging. When AC charging, it indicates the power coming into the car, and other power uses will pull power from that feed and reduce the available charging power. The radio, lights, USB ports have a very small effect. HVAC has a significant effect in hot and cold weather. For example, sitting in a hot car with AC on and a slow AC charger will leave little for the battery to charge.

When Supercharging, the power indication is the power going to the battery. Using HVAC will not change the battery charge power, unless the battery is at a low SOC and can use all the available power from the Supercharger.

Li ion batteries top balance, therefore the bms is balancing all the cells to the same voltage. As there roughly 7000 individual cells this could take awhile. It is recommended to top balance every two to three months. This is a very rudimentary explanation, I am sure there are more experienced Tesla owners who could give you a more detailed explanation. Hope that helps.

Tesla battery packs have no means of isolating the bricks (Tesla nomenclature for sets of cells in parallel) to balance when charging. Balancing is done when the car is in stand-by or asleep. It will use a bleed resistor to pull down high bricks until they're all within a 5mV tolerance. More here: Battery Management System - What I Learned At Tesla Service Center

 

[anon125110]

Sitting in the car with a/c or heat? Listening to radio? Charging cell phone?

The 1 kW figure means up to about 1 kW, not 1000 Watts exactly. The display will never read 0.1 kW.

I guess it can take an hour+ to get to 100.0% from 99%.

Cant see in picture but I did switch from mile display to percent and it was at 100% not 99%