battery-feature-lab 0.1.1

Feature extraction pipeline for battery cycling, BDS exports, and LLM-ready battery diagnostics.

BFL: Battery Feature Lab

BFL extracts battery cycling features from BDS-style exports and common cycler tables. It turns raw time-series data into feature tables for SOH/RUL modeling, feature screening, explainability, and compact diagnostic summaries.

Features

• Cycle summaries: capacity, energy, efficiency, C-rate, voltage, temperature, and rest time.
• Early-life curve features: Delta Q(V) variance, norms, quantiles, and related statistics.
• ICA/DVA features: dQ/dV and dV/dQ peaks, locations, widths, heights, and areas.
• Relaxation features: voltage drop, slopes, interpolated voltages, and exponential fits.
• Stress features: SOC, voltage, current, C-rate, temperature histograms, and high-SOC rest time.
• EIS descriptors when impedance columns are available.
• Rule-based degradation tags for LLI, LAM_PE, LAM_NE, resistance growth, and related evidence.
• LLM-ready JSONL summaries for downstream review or diagnostic workflows.

Installation

From PyPI:

pip install battery-feature-lab

From a local checkout:

python -m pip install -e ".[dev]"

Quick Start

bfl extract input.csv --output-dir out --cell-id cell_001 --nominal-capacity-ah 1.1

The longer command name is also available:

battery-features extract input.csv --output-dir out --cell-id cell_001 --nominal-capacity-ah 1.1

Diagnostic thresholds are configurable:

bfl extract input.csv \
  --output-dir out \
  --nominal-capacity-ah 1.1 \
  --datasheet-max-discharge-c-rate 5 \
  --high-soc-rest-threshold 0.25

Input Data

BFL accepts CSV, TSV, JSON, JSONL, and Parquet files. Input data can use common cycler/BDS column names. The reader normalizes aliases to:

time_s, voltage_v, current_a, temperature_c, charge_capacity_ah,
discharge_capacity_ah, cycle_index, step_index, step_type

At minimum, the input should contain time, voltage, current, and enough cycle/step information to identify charge, discharge, and rest periods. If cell_id, cycle_index, or step_type is missing, BFL can infer or fill parts of the schema from the file name, current sign, and command line options.

Optional EIS columns are:

frequency_hz, z_real_ohm, z_imag_ohm

Outputs

BFL writes non-empty tables to the selected output directory:

out/
  normalized_timeseries.parquet
  cycle_features.parquet
  delta_q_features.parquet
  ica_dva_features.parquet
  relaxation_features.parquet
  stress_features.parquet
  degradation_tags.parquet
  llm_context.jsonl
  run_metadata.json

Validation

Run the offline self-test:

python scripts/validate_on_dataset.py --synthetic 12

Run validation on a folder of per-cell CSV files:

python scripts/validate_on_dataset.py --data-dir path/to/cells --nominal-capacity-ah 1.1

Python Usage

from pathlib import Path

from battery_feature_lab.pipeline import FeaturePipeline, PipelineConfig
from battery_feature_lab.schemas import ExportConfig, FeatureConfig, ReaderConfig

pipeline = FeaturePipeline(
    PipelineConfig(
        reader=ReaderConfig(cell_id="cell_001"),
        features=FeatureConfig(nominal_capacity_ah=1.1),
        export=ExportConfig(output_dir=Path("out")),
    )
)

tables = pipeline.run("input.csv")

Development

python -m pip install -e ".[dev]"
python -m pytest
python -m ruff check .

License

MIT License. See LICENSE.