Long time lurker, etc. This seems like the closest on-point discussion for me, & couldn't quite find info on this.
Been driving the 2016 30kwh for several months (& basically very happy!). Recently had two substantial (hypermiling to avoid turtle) "range underperformance" experiences and am trying to chase down why using LeafSpy logs. It seems that Hx might
be a suspect. Really want to chase it down to have an idea of how to account for it. (Less range is one thing, but unexplained significant underperformance is a special kind of bad.)
The greater-than-expected loss of GIDs seems to happen on fairly long net-climb segments. An example of two runs over the same leg:
Same time of day, similar temp
Similar load (700? lbs including driver)
Windless (less than 1mph according to weather station history)
Minimal (115W avg) & no A/C
Similar tire pressures (41-43 PSI at this stage)
Similarly balanced pack at this stage, dV ca 15mV
Similarly hot pack after 2 QCs (121-123 F max, 115-117 min)
20 miles, 1150ft net climb, not much up & down
average speeds of 45.5. and 46.5mph. Fairly low variation (rural highway with bends etc.)
Range chart says ~53 GIDs for mileage at 4.7 mi/kwh (50mph flat) & 22 GIDs for net climb at 1.5kwh/1000ft. Actual use:
91 and 99 GIDs, or 16-25% over
. On slightly lower speeds to boot. I know GIDs are at best a BMS-interpreted value, but if all the modeling error is in the speed it's like 65mph instead of 45; if it's all in the elevation gain it's 2.4kwh/1000ft instead of 1.5.
Is it possible one culprit is fairly high internal resistance? I.e. the longer-term greater power demand of hill climbing leads to disproportionately high energy loss due to internal resistance? Or should I be looking at the transmission fluid or some other drivetrain gremlin? (Alignment? but how does the alignment know you're going up hill?)
Or is this mostly down to GIDs are a convenient fiction and just have to assume that sometimes (in the 30-50% range?) they're just...low energy?