Why does a battery dip and spike when it gets to 0% or 100%

Why does a battery dip and spike when it gets to 0% or 100%

Notice a sudden drop in the battery’s State of Charge (SOC), like from 8% down to 0%?

This doesn’t necessarily mean that the battery’s remaining energy was lost or used up. Instead, it often reflects a calibration correction, where the system adjusts its reading to better reflect the actual state of the battery. This is a normal part of how the system maintains accurate SOC reporting over time.

SOC drop from 9% to 0%

A similar scenario applies if you ever notice a sudden spike in the SOC say, from 94% to 100%.

This too is typically a correction rather than an actual rapid charge. These recalibrations help keep the system’s estimates aligned with the battery’s true capacity.

SOC spike from 94% to 100%

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