Validation of HPPCALC

Abstract

HPPCALC 2.1 was developed to analyze the raw data from a PNGV Hybrid Pulse Power Characterization (HPPC) test and produce seven standard plots that consist of resistance, power and available energy relationships. The purpose of the HPPC test is to extrapolate the total power capability within predetermined voltage limits of a prototype or full production cell regardless of chemistry with respect to the PNGV goals as outlined in the PNGV Testing Manual, Revision 3. The power capability gives the Electrochemical Energy Storage team the tools to compare different battery sizes and chemistries for possible use in a hybrid electric vehicle. The visual basic program HPPCALC 2.1 opens the comma separated value file that is produced from a Maccor, Bitrode or Energy Systems tester. It extracts the necessary information and performs the appropriate calculations. This information is arranged into seven graphs: Resistance versus Depth of Discharge, Power versus Depth of Discharge, Power versus Energy, Power versus Energy, Energy versus Power, Available Energy versus Power, Available Energy versus Power, and Power versus Depth of Discharge. These are the standard plots that are produced for each HPPC test. The primary metric for the HPPC test is the PNGV power, which is the power at which the available energy is equal to 300 Wh. The PNGV power is used to monitor the power degradation of the battery over the course of cycle or calendar life testing.