The objectives of this analysis were: 1. to describe the data profile in the ICDE database for batteries and to develop qualitative insights in the nature of the reported events, described by root causes, coupling factors, and corrective actions; and 2. to identify the failure mechanisms and phenomena involved in the events, their relationship to the root causes, and possibilities for improvement. Regarding the first objective, this analysis identified that only 10% of all ICDE events of batteries were complete or partial CCFs. The most frequent failure mode of batteries is "failure to run" (82%). It is noted that batteries typically fail over an extended period due to slow degradation of capacity. Regarding the second objective, the additional categorizations led to results that agree well with those derived for the first objective. The ICDE events of battery failures have been analyzed and the failure mechanisms and symptoms taken into account in order to identify the real problems and, therefore, to study the defences against them. Basically, the battery failures were dominated by Design (50%), and Maintenance / Tests (42%). In fact, all three complete CCFs are related to deficient maintenance procedures. Prevention methods and corrective actions are closely related. The ICDE definition of "corrective action" refers to action taken to prevent future recurrence of the same event. Additional protection methods identified include alarms and surveillance of the circuit continuity. Most CCF events were discovered during tests (56%) and maintenance (24%). The fact that 80% of the events studied were revealed by maintenance or test may indicate that this protection mechanism is already effective and there is no need for improved protection though improvements to maintenance/test methods.
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