Feature Battery Health

Battery health

The integration learns your EV battery's usable capacity from the same recorded charging sessions used for charging history — no REST quota, all derived from the stream.

How it's learned

A wide-range charge (say 20 → 80 %) that adds a known number of kWh implies the capacity of the whole pack: if 30 % of the battery took X kWh, the pack is roughly X / 0.30. Averaging across many such charges cancels the noise from temperature, charging speed and measurement error.

The Battery Health sensor

Surfaces as one Battery Health sensor per EV:

• State — usable capacity in kWh.
• Attributes — vs-new percentage, sample count, and a capacity-vs-mileage trend.

Learning mode

It reads Learning (n/10) until it has enough good samples and the estimate agrees with BMW's own capacity figure. A suspicious number is withheld rather than shown — a health figure that jumped around would be worse than an honest "not sure yet."

To reach a confident number faster, do a few wide-range charges (a large SoC swing in one session) rather than many small top-ups.

Viewing it

Use the view: health card: a gauge (percentage of the as-new pack) with the capacity-vs-mileage trend below.