Statistics, Numbers, Patterns, Etc. RE: Battery Charging Range

[PIOOD]

My 75D did something I've never seen before:

It did not allow charging past 96%. Usually, it lets me charge to 100%.

Is that because I drained it under 10 or 5%?

I read one post where - or maybe I heard it - that someone's charge couldn't go over 97%.

I tried soft reset, and unplugging the Supercharger twice, but both did not make the charging faster than 2 - 4 miles per hour.

When it capped me at 96% and said "complete" I just gave up and left.

 

[Tam]

...
It did not allow charging past 96%. Usually, it lets me charge to 100%...

It's a mystery but I guess it's because of the inaccurate Battery Management System calculation.

It wants 100% and 0% to figure out the capacity but that's very bad for your battery.

So the compromise is to charge it up to 90% instead so that the calculation won't be too off over time.

What that means is only the calculation is wrong--new 96% is equivalent to old 100% with one same range and same capacity.

You might want to ask Service Center to recalibrate the calculation or to make sure there's something else going on here.

 

[PIOOD]

It's a mystery but I guess it's because of the inaccurate Battery Management System calculation.

It wants 100% and 0% to figure out the capacity but that's very bad for your battery.

So the compromise is to charge it up to 90% instead so that the calculation won't be too off over time.

What that means is only the calculation is wrong--new 96% is equivalent to old 100% with one same range and same capacity.

You might want to ask Service Center to recalibrate the calculation or to make sure there's something else going on here.

Thank you!

I will also let the other friend know this. I'm communicating with some interested members over cell - so I can't remember if he had mentioned the issue I brought up here only by phone.

 

[PIOOD]

Just an update that the 75d did charge to 100% tonight. It said "5 more minutes" until completion, but it looked like it was taking way longer and never said "complete." So I just unplugged and left. There was about 20? stalls... I was the only one there (almost always the story). In my area, people like to charge their cars / teslas at home.

There was a helicopter above me circling with lights, and police sirens, police yelling some instructions. So most people feel scared of the supercharging areas at night. Another reason they're so empty.

I bring up I'm the only one cuz someone said it's rude to charge to 100%. But I usually only charge when no one else is there.

 

[ucmndd]

I’ve had this happen a couple times over the last ~90k miles, usually after not charging to 100% for a while. It has always rectified itself after a second or third attempt to charge to 100%. Like Tam suggests, it’s most likely a calibration issue for the BMS.

It wants 100% and 0% to figure out the capacity but that's very bad for your battery.

This is a massive overstatement. Don’t be afraid to charge your battery to 100% or run it low when you need to. It is not “very bad”.

Just an update that the 75d did charge to 100% tonight. It said "5 more minutes" until completion, but it looked like it was taking way longer and never said "complete."

When charging to 100% the car will sometimes trickle charge for 30+ minutes once it reaches “100%”, balancing cell groups, etc. it’s normal.

 

[PIOOD]

I’ve had this happen a couple times over the last ~90k miles, usually after not charging to 100% for a while. It has always rectified itself after a second or third attempt to charge to 100%. Like Tam suggests, it’s most likely a calibration issue for the BMS.


This is a massive overstatement. Don’t be afraid to charge your battery to 100% or run it low when you need to. It is not “very bad”.



When charging to 100% the car will sometimes trickle charge for 30+ minutes once it reaches “100%”, balancing cell groups, etc. it’s normal.

Thank you. I'll let you know if I get idle charges. Sometimes I can't tell if the car is done charging yet.