Is this charging speed normal for 2018 75D ?

[vegasko]

We have 75D September 2018.

Charging is very very slow when comparing our MY 2021. And also when comparing M3 standard range. It can take more then 1.5-2 hours vs M3 SR.
Both cars have simirar range.

Is it normal? If not, what we shold do?

 

[Tam]

...Is it normal?...

Please clarify:

2018 Model S 75D=1.5-2 hours?
2021 Model Y=very fast?
xxxx Model 3 SR=1.5-2 hours?

 

[ucmndd]

Lol, you have to provide an actual number if you want someone to tell you if it’s normal or not.

Yes, it will be slower than a 3/Y. An optimal charge session for a 75 on recent firmwares will max out at about 120kw around 20% state of charge and taper linearly from there. Once above ~30% your speed in kw will generally be 110 minus current state of charge (for example if your battery is at 40% you should expect to see a charge rate of approximately (110 - 40) = 70kw.

 

[vegasko]

Well one example - charging MS from 10-90% at chargepoint station takes almost 10 hours.
M3 takes around 8 hours.
And MY with 330 miles takes 8-9 hours.
Im doing this daily, driving each car every other day and using same stations all the time.
Same thing goes with home charging.
Charging MS takes always more time

I just want to know if thats normal

 

[AustinP]

M3 SR = 50kWh vs S75 = 75kWh so it makes sense that the S, with a larger battery, needs more time.

The odd number is maybe the MY, which is a battery similar in size to the S75 (75kWh).

Assuming your numbers are to charge to 100%, I'd argue that the S reduces charge power (kW) above 80% more than the newer cells in the Y do. Hence the longer charge time.

 

[vegasko]

So S with larger battery needs more time? I tought it was oposite. MS and M3 have same mileage range

 

[AustinP]

You can compare battery capacity, kWh, to gallons: the larger the tank, the more time it takes to fill it in.
MS and M3 have similar mileage range as these are two different cars, with difference consumption, due to different efficiency. M3 benefits from lighter weight too.

 

[brico84]

Your charging rate at a level 2 charger, which is what it seems your are using, will be the same amount of kw per hour and does not taper based on state of charge.

 

[ucmndd]

Again, if you want help, you need to provide actual data. “8-9 hours” is meaningless when we don’t know what state of charge you’re starting at, what you’re finishing at, etc.

What does your car report as a charging speed while it’s actually charging? Provide numbers in volts / amps / kilowatts.

 

[Rocky_H]

We have 75D September 2018.

Charging is very very slow when comparing our MY 2021.

At first, we thought you were talking about Supercharging, which is very dependent on the cable thickness in the cars, and the battery chemistry, which are vastly different for an old 2018 Model S versus the much newer 3 or Y. But, it turned out that is not what you were talking about.

Well one example - charging MS from 10-90% at chargepoint station takes almost 10 hours.
M3 takes around 8 hours.

In this case, where you are talking about low power 240V kind of charging, there will be no difference at all. They are charging at exactly the same speed.

@AustinP was using a good analogy about gas filling. Maybe I can expand.

Let's say you are using the same gasoline filling nozzle to fill two vehicles. The nozzle is filling at a certain speed of gallons per minute. It is exactly the same for the two vehicles. But what are the vehicles? Maybe one is a big F-350 dually pickup truck, while the other is a tiny Ford Fiesta econobox car. They get very different miles per gallon efficiency, right? So looking at the filling rate in a unit of miles per minute instead of gallons per minute is going to make them look really different. That's kind of what you're doing with trying to compare a Model S versus a Model 3 in terms of the rated miles filling speed. They have very different efficiency, so that's going to look weird when they are actually receiving energy at the same speed from that Chargepoint station.