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Charging over set limit

Charging over set limit

About a month ago, my M3 charged over the charge limit (90%) to 93% and lost 1% of battery capacity. Expected range at 90% for my LR AWD was 275miles for months and dropped to 272. Added the incident to a pending SC appointment and the response was it must have been a glitch and told me recalibrate. I did that and 90% is back to 274/275ish. Yesterday, found the battery charged at 91% and 275miles and as soon as i started moving (about 2feet), it dropped to 272. Is this normal behavior for the battery at 12k miles?

Bighorn | September 5, 2019

Normal, described behavior. Thoughts that the upped final charge state may be due to a change in the battery temperature. A 1% difference is both insignificant and beyond the accuracy of the measurement.

httran26 | September 5, 2019

Most likely the car did not overcharge over the limit. It most likely charged to 90% and stopped. As the battery cooled or heated up, the % changes. The BMS is just estimating the best it can. The value changes based on many different factors. It happens to me all the time.

As for the miles dropping as soon as you started moving, this is normal as well. Same case as the BMS estimating the best it can. I've seen my % droping from 75% to 74% after moving 1 foot. I'm at 21k miles.