Battery knowledge · Testing methods
Hybrid pulse power characterisation
A test that applies a short discharge pulse and a short charge pulse at each state of charge, from which resistance and power capability are read as a function of SOC. It is the standard source of equivalent-circuit parameters. [1] [2]
- Abbreviation
- HPPC
Example
Voltage response and relaxation
At τ = 20 s, 63.2% of the step response is complete; a relaxation retains 36.8%.
Two separate analytical experiments; normalized voltage, not measured data.
Explore the graph
One time constant completes about 63% of a first-order voltage change.
At τ = 20 s, 63.2% of the step response is complete; a relaxation retains 36.8%.
τ = RC; step response = 1 − e^(−t/τ)
Illustrative model. Two separate analytical experiments; normalized voltage, not measured data.
Use in Lemonergy
Design protocol or analysis tool
Inspect pulse characterization
HPPC alternates pulses, moves SOC and includes long rests.
Equation or tool to use
- Rest
Allows relaxation
Inputs & settings
- s
- Pulse
Excites charge/discharge
Inputs & settings
- a
- pulseS / restS
- Repeat
Repeats SOC points
Inputs & settings
- count
This overview identifies the components to use. Follow the example in Lemonergy for their connections and settings.
- Open HPPC pulse characterization.
- Compare immediate voltage change and recovery.
Example. 0.2 V change after a 10 A step gives 20 mΩ by ΔV/ΔI on the same cell/pack basis.
Observe. Long rests differ from the immediate resistive jump.
The estimate depends on timing, temperature and state; this is not AC impedance spectroscopy.
Open Design → Protocol bench →References & further reading
Technical references
- Battery Test Manual For Electric Vehicles, Revision 3
Jon P. Christopherson · Idaho National Laboratory · 2015
Technical reference · Performance characterization, pulse resistance/power, life testing and reference performance tests; historical 2015 edition.
- DOE Energy Storage Handbook, Chapter 16: Energy Storage Performance Testing
Sandia National Laboratories
Technical reference · Section 2.1.2.1 explains capacity, C-rate and the distinction between capacity and energy; also covers pulse characterization.