Risk Assessment of Lithium-Ion Battery Manufacturing and Recycling using Fuzzy FMECA

The increasing frequency and severity of lithium-ion battery fires have raised global concerns about their safety across the entire lifecycle—from production and use to recycling and disposal. Recycling facilities, in particular, face elevated process safety risks due to the complex handling of thermally unstable, flammable, and toxic materials. Incidents such as the 2024 recycling plant fire in Missouri and numerous battery-related aircraft fires reported by the Federal Aviation Administration emphasize the urgent need for systematic risk assessment approaches. This study applies Fuzzy Failure Mode Effects and Criticality Analysis (Fuzzy FMECA) to evaluate the risks associated with lithium-ion battery manufacturing and recycling processes. The method integrates expert judgment under uncertainty to prioritize failure modes related to thermal runaway during collection, flammable vapor emissions, combustible dust generation, and hazardous chemical handling. A comprehensive fuzzy inference system is developed using 125 fuzzy rules, enabling risk prioritization through a Mamdani-type knowledge base. The defuzzification is carried out using the Center of Gravity method to convert fuzzy outputs into actionable risk rankings. By identifying and ranking the critical risks using fuzzy logic, the study provides a structured framework for improving process safety in battery manufacturing and recycling operations. The findings highlight the importance of proactive safety management as battery recycling becomes central to circular energy economies and environmental sustainability.