Mäta HRR från Li-jonbatterier med hjälp av OCC (oxygen consumption calometry) och andra metoder

Sammanfattning: One of the most important parameters to measure in the fire discipline is the heat release rate (HRR). Therefore it is very important that these measurements are accurate and as correct as possible. The most common method for measuring heat release rate of fires is the OCC method (oxygen consumption calorimetry). The method is based on the relation between oxygen in the surroundings and the exhaust gases. Problems with the method can arise when the fuel that is burnt develops oxygen by itself, something that a lithium-ion battery do. One solution to this problem could be to use a different method to measure HRR. The method that is chosen to evaluate as an alternative to OCC is the SERA (sensible enthalpy rise approach) method. A comparison between the methods is conducted to evaluate if the SERA method can produce a result with less uncertainty than that of the OCC method. The comparison is conducted through a series of calculations and assumptions. The assumptions that are made in the comparison is deemed to induce to large of an uncertainty in the result to state that one method is better than the other one and instead it is suggested that further research should be conducted to be able to conclude which method is better. The results that can be concluded from the work is that a measurement with the SERA method has to be conducted very carefully to have a chance to be an improvement of a measurement with the OCC method. The second result that can be concluded from the work is that the produced oxygen from the lithium-ion battery induces a significant uncertainty in the OCC method, resulting in an underestimate of the HRR.