Scope This dataset contains electrochemical impedance spectroscopy (EIS) data collected from a batch of 21700 cylindrical NMC811 lithium-ion cells at a state of charge (SoC) of 30%. The measurement was performed using a Keysight SL1007A Scienlab Battery Test System in galvanostatic mode. Data Each CSV file (IDXX.csv) contains the results of the EIS test performed on the battery cell with the corresponding indentifier IDXX (where XX spans 01 - 54). RDF Metadata Filename Description Format Usage keysight_eis_csvw_schema_0.1.0.json Metadata describing the table schema of the tabular data using terms from the CSVW, DCAT, and BattINFO resources. JSON-LD Enables agents to understand the structure and meaning of the tabular data in the CSV files. metadata.jsonld Metadata describing the tests, cells, and results contained in this record. JSON-LD Enables integration into semantic web and FAIR data workflows. metadata.html HTML page that embeds the JSON-LD metadata for machine agents HTML Helps web crawlers to find and process the metadata