Battery knowledge · Testing methods
Isothermal calorimetry
Holding a cell at constant temperature inside a calorimeter and measuring the heat it gives off, down to microwatts, while it cycles or rests. It separates reversible entropic heat from irreversible losses and reveals the parasitic heat of slow side reactions, a quick indicator of how long a cell will last.
- Also called
- isothermal microcalorimetry, IMC, heat-flow calorimetry
Example
Current and resistive heating
At 5 A: 0.5 W. At 10 A: 2 W.
Resistance is constant; reversible entropic heat and other losses are excluded.
Explore the graph
Double the current and ohmic heating increases fourfold.
At 5 A: 0.5 W. At 10 A: 2 W.
P_heat = I²R
Illustrative model. Resistance is constant; reversible entropic heat and other losses are excluded.
Use in Lemonergy
Record specimen, state, instrument, temperature and timing.
This is a reference concept. No executable Lemonergy block has been verified for this term.
References & further reading
Further reading on this topic
These sources provide broader context; they are not presented as citations for every statement in this entry.
- Battery Test Manual For Electric Vehicles, Revision 3
Jon P. Christopherson · Idaho National Laboratory · 2015
Topic background · Performance characterization, pulse resistance/power, life testing and reference performance tests; historical 2015 edition.