| Abstract Title |
FTA / FMEA Safety Analysis Model for Lithium-ion Batteries |
| Abstract Author(s) |
Anura Fernando, Thomas Lanzisero |
| Abstract Presenter |
TBD |
| Abstract |
The robustness of system reliability review and root cause analysis relies on the use of a systematic approach and appropriate methods and tools. This is particularly important when the focus is on safety. Conventional analysis tools such as Fault Tree Analysis (FTA) and Failure Modes and Effects Analysis (FMEA) can be combined and modified to achieve this outcome. Such results can demonstrate improvements in safety and also help to identify and prioritize areas requiring further research. In this presentation, this combined FTA / FMEA approach is applied to the safety analysis of common secondary Lithium ion battery technologies, such as 18650 cells with capacities up to 2900 mAh*. Specifically, the approach is adapted to meeting defined safety objectives by combining the output of FTA, which drives down to specific “basic events” from top-level hazards, and a “safety” FMEA. The Safety FMEA (SFMEA) expands upon those basic FTA events from the perspective of root-cause analysis of failure and their local and systemic impact relative to safety. The SFMEA is a specially focused variation of the more common Design FMEA (DFMEA) that addresses general design goals such as proper product operation. This combination of the deductive, top-down (FTA) and inductive, bottom-up (FMEA) analysis models has been developed to map top-level hazards to low level faults, such as failure modes of components or materials and standards-based test protocols. This technique is scalable to the material, component, assembly, or system level, while maintaining full traceability to demonstrate the extent of coverage as well as to expose areas where future research is needed.
* - The scope of this effort is initially focused on single, rechargeable (secondary), lithium ion 18650 (nominal 18 mm diameter, 65 mm height) cylindrical cells, nominal 3.4-4.0 V and 1200-2800 mAh. Chemistries include lithium cobalt oxide (LiCoO2) and lithium ion polymer cells for applications such as information technology equipment and consumer electronics equipment, as well as lithium manganese oxide (LiMn2O4) cells for power tools. |
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