1. Questions/comments for EVS1548-617 (CA)
Slide 9 - Clarify what is meant by ”minimal invasive” – what are the limits of ”minimal”?
Photos on slide 8 suggest that the modules tested are relatively open and that cell surfaces are accessible from the outside. Have you considered necessary modification when this is not the case, i.e. dismantling of module structure, cutting into barrier structures, etc?
Cell spacing may not allow 1 mm device inserted between the cell surfaces, e.g. there could be thermally insultaing material filling up the space. How would the test method robustness and applicability by affected if onlyu the outer surface of periiferally located cells are accessible for attachment of the TRIM?
Slide 12 "ignition of vented gases"
The severity of the effect of gas combustion also depends on the amount of accumulated amount in the flammable mixture before ignition. What do you consider to be a representative timing to ignition with respect to amount of gas/composition of mixture?
How do you justify forced ignition if this is not representative with battery system safety behavior, as indicated by the standard outcome of your testing? How does this reflect field experience of likelihood of gas ignition?
Slide 16 – Fire or smoke deliberation - with fire there is likely to be smoke too. Does this mean that you consider smoke from fire as less problematic than “smoke” from venting?
Slide 21 - What is the estimated added combustion energy due to higher O2 levels from drilled holes into an airtight battery enclosure and how does this affect the containing ability of the REESS design?
Comments
Slide 30 - Comparison of safety behavior of non-automotive applications and batteries is not straight forward. It is not enough with “high quality cells”, also need comparable system design and battery management technology for relevant comparison of risk. TP safety behaviour is not defined solely on cell level.