Influence of Active Material Heat Release Kinetics on Thermal Runaway Following an Internal Short-Circuit

Field-failures prompted the recent recall of Li-ion battery packs used in laptop computers. We term as a field-failure the safety incident that occurs when the lithium-ion pack is used under normal, non-abusive conditions. These incidents are very rare, occurring in less than one in a million cells. Note that these field-failures occurr in cells from lots which pass standard abuse tests, such as UL tests. In this paper we will discuss how the properties of the active material influence the propensity for fieldfailure.