When looking for the correct chemistry ID for Impedance Track gauges, the GPCCHEM tool should be used. This tool helps find the best matching chemistry ID for the battery. The chemistry ID contains the baseline Open Circuit Voltage (OCV) vs. Depth of Discharge (DoD) table used for gauging. It also contains the Rb table (Rb explained in SLUA450) and the Ra table, which is updated in the learning cycle.
Common misconceptions about the chemistry ID:
- If a chemistry ID has the same capacity you can use it for your battery – the capacity of the chemistry ID does not matter, the most important fitting is the OCV vs. DoD table.
- You can upload the chemistry ID without the EV2400 – the EV2400 is required to upload the chemistry ID since the data is proprietary.
- The chemistry ID is not critical for gauging – The OCV vs. DoD table along with the other information is very critical to gauging.
Note on bullet point 2:
Only one EV2400 is needed to created the golden image for the gauge that is used in production. Then other methods can be used to program the SREC, BQ.FS, DF.FS, or GM.FS files which contain the chemistry ID information.