I frequently supercharge my S and 3 at an urban supercharger nearby. I'm very familiar with the charge speeds at all battery charge levels. However in the past week sometime, something interesting has occurred.
It's behaving like my car thinks it's a full speed supercharger and is directing the stall to send power levels accordingly. For example, when my 3's battery is about half full (more or less), I would expect around 100kW of power from a full speed supercharger and 72kW at an urban one. Instead, I was getting 50kW. As the battery approached 60% charge, I would expect around 80kW from a full speed supercharger but I was getting 40kW instead. This trend continued where I was getting pretty much half of what I would expect from a normal supercharger.
Does anyone know how the car directs the charger to select the power level? Does the car tell it to use a percent of its available power or does it tell it a specific power value? Would be interesting if my car thought the charger was capable of 140kW and was telling it to use a percent based on that number. Would explain why everything was halved since this was an urban charger only capable of 72kW.
I tried 5 different stalls so this wasn't a cabling issue...they all behaved the same. I'll try again today and see if the behavior is any different. Maybe I'll try my S as well.