UL 9540A does not ask whether a battery burns - given a forced thermal runaway, it measures how the event develops at each level of assembly, so that installation codes and authorities can judge spacing, venting and suppression on data.
The levels
Cell level establishes whether a cell can be driven into thermal runaway and what it vents. Module level shows whether runaway propagates between cells in a module and what a module releases. Unit level - where our heat release calorimetry applies - measures the complete unit's fire behaviour, including heat release rate under a collection hood. Installation level addresses room-scale behaviour and suppression. Around the calorimetry sit abuse and exposure configurations: cell abuse chambers in the AEC/EPT range and the ECE R100 battery fire exposure test for vehicle batteries.
Equipping for battery work
Start from the level your customers' approvals require - most equipment decisions follow from that single answer. The methods overview in our blog, battery thermal runaway test methods, explains the test logic level by level.