The nomenclature used to describe the cell and cycling conditions is evolving as we encounter more diverse use cases. The categorization below is based on the data we currently have available. Please let us know if you have feedback or additional data you’d like to share.
Cycling data broadly falls into two categories: (a) constant current square wave cycles and (b) application-specific duty cycles.
(a) Constant current square wave cycles: a cell is charged and discharged in a particular state of charge or voltage range for the bulk of cycling. The full charge or discharge is carried out at a constant current.
(b) Application-specific duty cycles: a cell is charged and discharged with several different currents in a single repeating segment. This could be a named duty cycle, such as the Artemis urban drive cycle, or a general category of duty cycle, such as frequency regulation or peak shaving (for grid applications).
The Cell ID is structured as follows to give users quick insight into the study as they scroll through the database:
institution code_(original cell ID)_form factor_cathode_temperature_min-max SOC_charge rate/discharge rate_(letter)
*components in parentheses are optional, depending on the study
Parts of the cell ID or metadata that relate to cycling conditions such as SOC and rates are based on the conditions for the bulk of cycling. The cycling conditions during reference performance tests or capacity checks are typically different. If available, more details on conditions during reference performance tests are provided in the Studies page.
A breakdown of the Cell ID:
1) Institution Code: 3-4 letter abbreviation for the institution that generated the data
2) Original Cell ID: this is an optional entry intended for cells that were previously assigned a cell ID in a public forum such as a publication or group website.
3) Form factor: the form factor of the cell
4) Cathode: cathode chemistry
5) Temperature: the temperature of the environment in Celsius
6) Min-Max SOC: the range of state of charge during cycling, given as a percent
7) Charge rate/Discharge rate: the C-rate applied during charge and discharge. A rate of 1C corresponds to the current that will discharge the full capacity of a battery in one hour.
8) Letter: if there were replicates, each cell is assigned a letter at the end of its ID
Based on https://github.com/battery-lcf