Battery degradation calculation automatic

[springfall2008]

No description provided.

[Copilot]

Pull request overview

Adds automatic battery capacity tracking/scaling based on historical charging data, with documentation, configuration, charting, and unit coverage.

Changes:

• Adds battery_scaling_auto config handling and default state.
• Adds battery size tracking sensors/history and soc_kw support in find_battery_size().
• Adds a BatteryDegradation chart and expands find battery size tests.

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
docs/apps-yaml.md	Documents the new automatic battery scaling option.
apps/predbat/web.py	Adds a BatteryDegradation chart page/menu item.
apps/predbat/tests/test_find_battery_size.py	Adds tests for soc_kw and auto scaling behavior.
apps/predbat/predbat.py	Initializes the new auto-scaling flag.
apps/predbat/inverter.py	Implements battery size tracking and soc_kw history conversion.
apps/predbat/fetch.py	Reads battery_scaling_auto from config.
apps/predbat/config.py	Adds schema support for battery_scaling_auto.

Comments suppressed due to low confidence (4)

apps/predbat/inverter.py:603

• Persisting the 8 kWh fallback into soc_max makes the fallback look like a configured nominal capacity on later inverter initializations. If the first run has no usable history, subsequent runs will clamp auto sizing against 8 kWh and can never grow to the real capacity; the previous code only used the fallback in memory, so later history could still establish the real size.

        if not self.soc_max or self.soc_max <= 0:
            self.log("Warn: Unable to determine battery size for inverter {}, setting to 8 kWh default, you must set soc_max in apps.yaml or wait until enough data is collected to estimate battery size".format(self.id))
            self.soc_max = 8.0
            self.base.set_arg("soc_max", self.soc_max, index=self.id)
            self.base.set_arg("soc_max_nominal", 0, index=self.id)
            self.nominal_capacity = self.soc_max

apps/predbat/inverter.py:675

• Passing a configured nominal capacity into the soc_kw conversion prevents auto degradation detection for users who provide absolute kWh SoC. The derived percentage becomes soc_kw / nominal_capacity, so find_battery_size() will estimate the nominal capacity rather than the measured usable capacity; it should still derive the percentage scale from the observed kWh history when the goal is to measure degradation.

                if nominal_capacity and nominal_capacity > 0:
                    soc_max = nominal_capacity
                else:
                    soc_max = max(float(dp0(float(state["state"]))) for state in soc_kw_data[0]) if soc_kw_data and len(soc_kw_data) > 0 else None

apps/predbat/inverter.py:675

• The max(...) over soc_kw_data[0] converts every history state before any validation, so a common HA history value like unknown, unavailable, or an empty history list will raise and abort inverter initialization. The later per-state try block only applies after this maximum has already been computed.

                    soc_max = max(float(dp0(float(state["state"]))) for state in soc_kw_data[0]) if soc_kw_data and len(soc_kw_data) > 0 else None

apps/predbat/inverter.py:675

• Rounding the observed maximum kWh value to a whole number before using it as soc_max biases the capacity estimate, especially for common fractional battery sizes (for example 5.2 kWh is treated as 5 kWh). The auto estimate should preserve the measured kWh precision instead of applying dp0().

                    soc_max = max(float(dp0(float(state["state"]))) for state in soc_kw_data[0]) if soc_kw_data and len(soc_kw_data) > 0 else None