The BatteryDataset Object

The BatteryDataset object is the central object for the battery data toolkit. Extractors render vendor-specific data into the BatteryDataset, schemas describe its contents, and post-processing codes manipulate.

Using the BatteryDataset Object

The BatteryDataset holds different types of data about a battery in separate Pandas dataframes, and metadata describing the source of the data in a .metadata attribute.

Note

TBD: Describe the types of data

Loading and Saving

The battery data and metadata can be saved in a few different styles, each with different advantages.

HDF5

The HDF5 file format stores all data about a battery in a single file.

Note

Explain that we use pytables now, but that may change in the future

Multiple Batteries per File

Battery Data Toolkit supports storing data from multiple, related batteries in the same HDF5 file as long as they share the same metadata.

Add multiple batteries into an HDF5 file by providing a “prefix” to name each cell.

test_a.to_batdata_hdf('test.h5', prefix='a')
test_b.to_batdata_hdf('test.h5', prefix='b', append=True)  # Append is mandatory

Load a specific cell by providing a specific prefix on load

test_a = BatteryDataset.from_batdata_hdf('test.h5', prefix='a')

or load any of the included cells by providing an index

test_a = BatteryDataset.from_batdata_hdf('test.h5', prefix=0)

Load all cells by iterating over them:

for name, cell in BatteryDataset.all_cells_from_batdata_hdf('test.h5'):
    do_some_processing(cell)

Parquet

TBD.