This raw "SOC" value is clearly NOT actually THE remaining-energy number, but only related to it.
The SOC-Meter's displayed "percentage" value is just the raw value as a percentage of 281 ((raw * 100) / 281), without any fancy mapping.
Since MANY drivers have noted reduced "mileage" during the first bar, it is clear that this "SOC" number drops faster at the high end.
There are two main probable causes:
1. There is little/no/reduced Regen when the battery is near full, so the EV wastes energy braking.
2. This "pseudo-SOC" value might be derived from an estimate of the Battery Pack's "resting" voltage, which has a faster drop at 100% than at 50%.
We do not know how this "SOC" number is generated within the LEAF, but we do know that it goes up when we charge, can go up when we Regen enough, and usually goes down when we drive normally.
It might seem like charging to 90% or 95% (or about 11 Bars) might be an efficient choice.
See SOC/GID-Meter and CAN-Do Info
2011 LEAF, 2014 Tesla S85
2018 & 2019 Tesla Model 3
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