I charge my battery to 80% last night and woke up this morning. It was at 82. Does that mean my battery is getting stronger ???

[Dennone]

charge my battery to 80% last night and woke up this morning. It was at 82. Does that mean my battery is getting stronger ???

 

[GtiMart]

After you charge, the BMS might readjust battery capacity and that will reflect in displayed SOC. It can change by a few percent up or down. Sometimes this change is due to the battery temperature changing.

 

[Dennone]

Ok thank you

 

[rpiotro]

After you charge, the BMS might readjust battery capacity and that will reflect in displayed SOC. It can change by a few percent up or down. Sometimes this change is due to the battery temperature changing.

Yes! This. ^^^

 

[Shelburne]

I routinely charge my 2020 M3 to 80%. At 80% the range will be anywhere from 234 miles to 251 miles. Some of that fluctuation is due to the ambient air temperature.

 

[CyberGus]

That can work on the other direction too, for instance if the temperature drops significantly.

 

[Dennone]

Thanks for the info

 

[Tha_Ape]

Ok thank you

That kind of adjustment made me switch my max charge level to 75%. I'm probably paranoid, but I didn't want it going over 80% on a regular basis

 

[FOOLSLFDRVNG]

Seriously I thought I was going nuts.

 

[afadeev]

That kind of adjustment made me switch my max charge level to 75%. I'm probably paranoid, but I didn't want it going over 80% on a regular basis

Why is that?

 

[TulsaCoker]

I try and keep my change limit to 69% ....

 

[Tha_Ape]

Why is that?

Superstition... lol

Theres no definitive answer, but some people say not to charge over 80%. I dont need over 80% so I just dont.

 

[Ittirat V]

Me too, I won’t charge it over 80% by supercharger and slow charger.

 

[E90alex]

That kind of adjustment made me switch my max charge level to 75%. I'm probably paranoid, but I didn't want it going over 80% on a regular basis

75 vs 80 vs even 90 makes little difference if you’re worried about battery health. The magic number is 55% for most Teslas and 70% for LFP cars.

 

[Mikecm1]

If anything that would mean your battery is getting weaker. Your car would charge to 80, calibrate and be like oh crap, that's actually 82 because the battery has less capacity than I thought! Better adjust it.

But don't worry about it, it doesn't mean anything.

 

[Tha_Ape]

If anything that would mean your battery is getting weaker. Your car would charge to 80, calibrate and be like oh crap, that's actually 82 because the battery has less capacity than I thought! Better adjust it.

But don't worry about it, it doesn't mean anything.

That makes sense because after 2 yes my max charge is 302 (vs 326 new)

 

[ODWms]

I wonder how much of that 24 mile difference is actually degradation, rather than miscalibration. I'd bet it's more the latter than the former.

 

[rpiotro]

In a perfect world the state of charge for best life of the prior Lithium Ion batteries would be between 70% and 40%. Even Must said 80/20 is fine.

I do the 70//40 most days because I can. I have sufficient juice to go where I need to go.

If I'm going on a rare road trip I push it as much as needed but only then. Yes, I coddle the battery. I expect to own this car for a while.

 

[rpiotro]

75 vs 80 vs even 90 makes little difference if you’re worried about battery health. The magic number is 55% for most Teslas and 70% for LFP cars.

50-55% is the best for long term storage.

 

[UncleCreepy]

As with all things analog, the question is: how much of a difference does it really make if I let the battery sit at 90% vs. 50%? I regularly charge to 95% before I drive home and arrive at 90% which is when I park the car for 12-18 hours. The car is almost four years old, has about 120,000 km on the clock and the indicated range at 100% is now 462 km. It was 507 km when I got the car.

Even if I kept the SoC lower, calendar degradation would still happen.

Assuming the car can handle 1,500 full charge cycles and that the average range is only 400 km, that would still mean that the battery is good for 600,000 km (or about 372 ,000 miles). At this point I don't really worry too much about an extra percent of battery life time.