Charging beyond the set 90% limit

[BobAbooey]

My car charged past the 90% (292 miles) set limit today when charging at home. This is a first for me...

 

[Tam]

...This is a first for me...

Do you always set your charge to 90% or what's your usual setting?

 

[al503]

I've noticed this as well. I charge to 80% which is about 248 miles. I've noticed a few times that it's been charging to 251 miles.

Not a big deal to me by any stretch, though.

 

[Rockster]

Sometimes you just want one more slice of that delicious pizza...

 

[insaneoctane]

I've been occasionally seeing this on the last few firmwares. By the way, my data points to this not actually being overcharging. My data showed the vehicle stops charging at your requested level, but the range subsequently changes over the next few hours (possibly thermal changes due to new battery cooling algorithms?)

 

[Atari2600]

I noticed this charging to 80% and it went over about the same as your 90% charge is showing.

 

[woodisgood]

My car has done this occasionally. I doubt it’s anything to worry about.

 

[ElectricLee]

I used that trick and fooled my wife, i set her charge limit to 100% and then I moved it back to 90%. Hee hee

 

[JulienW]

I used that trick and fooled my wife, i set her charge limit to 100% and then I moved it back to 90%. Hee hee

Since charging to 100% and letting it sit stresses the battery and accelerates degradation why would you do this?

 

[ElectricLee]

Since charging to 100% and letting it sit stresses the battery and accelerates degradation why would you do this?

Joking

 

[ngogas]

Topped off line an ice. Lol

 

[NedH]

Since charging to 100% and letting it sit stresses the battery and accelerates degradation why would you do this?

Do you have a source for this information? Did you mean repeatedly charging to 100% stresses the battery? Why would charging to 100% and letting it sit stress the battery?

 

[boaterva]

I’ve seen this overcharging once in a while especially after a new firmware load. Cured by a reboot which I recommend after every firmware load. Usual steering wheel two scrollwheel reboot.

As for the post above, it’s well known that you never store Lithium batteries charged to 100% if you want them to last. For those of you with cell phones that say you do this all the time, how long do you keep your phone? I get a new one yearly through the iPhone upgrade program.

Even Tesla has the car complaining if you set it to charge to 100%. You really must not have been here too long. Or are joking.

 

[r1200gs4ok]

does charging to 90% each time cause any harm?

 

[JulienW]

Do you have a source for this information? Did you mean repeatedly charging to 100% stresses the battery? Why would charging to 100% and letting it sit stress the battery?

Many sources but here is the "bible" of battery info.

...Li-ion does not need to be fully charged as is the case with lead acid, nor is it desirable to do so. In fact, it is better not to fully charge because a high voltage stresses the battery. Choosing a lower voltage threshold or eliminating the saturation charge altogether, prolongs battery life but this reduces the runtime....

Charging Lithium-Ion Batteries
Basic to Advanced Battery Information from Battery University

 

[SSonnentag]

I've only seen this happen when a route was entered that required more than my set charge limit to reach the destination or supercharger.

I wonder if it is possible that the software has been tweaked to periodically charge higher to balance the cells....

It could be a graphical issue where the slider doesn't draw in the correct location. We've seen that issue with the mobile app in the past.

Interesting in any event.

 

[animorph]

does charging to 90% each time cause any harm?

Here's a couple of links to threads that have helpful links:
Jeff Dahn's recommendation on long term battery preservation

Battery Charging Best Practices

 

[SSedan]

Does it do this daily or is it possibly a rebalance event?

The thermal idea above seems worth considering too.

 

[JulienW]

Simple: Batteries are like many systems and there is not absolute best or worst but degrees of better and less good and LOTS of compromises. If you want your batt to last the longest then:

• Charge slowly (no Supercharging) to about 65% to 75%
• Use to about 55% to 65% and recharge slowly
• Never accelerate hard and pull energy from the batt as slowly as you can when you drive
• About 2 to 4 times a year charge slowly to 90% and immediately drive slowly and reduce to below 70%

If you do this your batt will probably last well over million miles. However you will get almost NO practical use of the car.

 

[r1200gs4ok]

Here's a couple of links to threads that have helpful links:
Jeff Dahn's recommendation on long term battery preservation

Battery Charging Best Practices

thank you sir