Battery (BMS?) problems after 200 t kilometers

[Matias]

Tesla taxis in Finland have had sudden battery problem after approximately 200 t kms. Warranty has covered these.

IIRC someone posted similar issue here and Tesla had told that it is BMS problem and that new software should fix this. Does anyone has any additional info about this? My guess is, that it is related to increased internal resistance.

 

[stopcrazypp]

Tesla taxis in Finland have had sudden battery problem after approximately 200 t kms. Warranty has covered these.

IIRC someone posted similar issue here and Tesla had told that it is BMS problem and that new software should fix this. Does anyone has any additional info about this? My guess is, that it is related to increased internal resistance.

One of the 200k mile Model S used for shuttle/taxi purposes had a BMS issue also (basically it can't estimate the end of charge accurately).
At 200,000 Miles, This Tesla Model S Experienced Only 6% Battery Degradation
From my limited knowledge of BMS, I'm guessing the issue is the SOC lookup table. The old BMS firmware probably failed to account for the characteristics of a pack at the extremes of its life cycle.

 

[MP3Mike]

The old BMS firmware probably failed to account for the characteristics of a pack at the extremes of its life cycle.

Or more likely they didn't know what a pack would look like after that mileage so they couldn't properly estimate it. That may be why they gave the Tesloop guy a new battery so that they could take their time and test/analyze the high mileage battery to help in updating the software. I guess they should hurry up with this as more and more cars are going to be crossing that threshold. (Who knows maybe the 8.1 update due in ~3 weeks will contain the BMS fix for this issue.)