Purpose The purpose of this study was to analyze the environmental trade-offs of cascading reuse of electric vehicle (EV) lithium-ion batteries (LIBs) in stationary energy storage at automotive end-of-life. Methods Two systems were jointly analyzed to address the consideration of stakeholder groups corresponding to both first (EV) and second life (stationary energy storage) battery applications. The environmental feasibility criterion was defined by an equivalent-functionality lead-acid (PbA) battery. A critical methodological challenge addressed was the allocation of environmental impacts associated with producing LIBs across the EV and stationary use systems. The model also tested sensitivity to parameters such as the fraction of battery cells viable for reuse, service life of refurbished cells, and PbA battery efficiency. Results and discussion From the perspective of EV applications, cascading reuse of an LIB in stationary energy storage can reduce net cumulative energy demand and global warming potential by 15 % under conservative estimates and by as much as 70 % in ideal refurbishment and reuse conditions. When post-EV LIB cells were compared directly to a new PbA system for stationary energy storage, the reused cells generally had lower environmental impacts, except in scenarios where very few of the initial battery cells and modules could be reused and where reliability was low (e.g., life span of 1 year or less) in the secondary application. Conclusions These findings demonstrate that EV LIB reuse in stationary application has the potential for dual benefit-both from the perspective of offsetting initial manufacturing impacts by extending battery life span as well as avoiding production and use of a less-efficient PbA system. It is concluded that reuse decisions and diversion of EV LIBs toward suitable stationary applications can be based on life cycle centric studies. However, technical feasibility of these systems must still be evaluated, particularly with respect to the ability to rapidly analyze the reliability of EV LIB cells, modules, or packs for refurbishment and reuse in secondary applications.

Offering a consistent, systematic approach to capacitive, piezoelectric and magnetic MEMS, from basic electromechanical transducers to high-level models for sensors and actuators, this comprehensive textbook equips graduate and senior-level undergraduate students with all the resources necessary to design and develop practical, system-level MEMS models. The concise yet thorough treatment of the underlying principles of electromechanical transduction provides a solid theoretical framework for this development, with each new topic related back to the core concepts. Repeated references to the shared commonalities of all MEMS encourage students to develop a systems-based design perspective. Extensive use is made of easy-to-interpret electrical and mechanical analogs, such as electrical circuits, electromechanical two-port models and the cascade paradigm. Each chapter features worked examples and numerous problems, all designed to test and extend students' understanding of the key principles.

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To access ground truth degradation information, we simulatedcharge and discharge cycles of automotive lithium ion batteriesin their healthy and degrading states and used this informationto determine performance of an autoencoder-basedanomaly detector. The simulated degradation mechanism wasan abrupt increase in the battery’s rate of time-dependent capacityfade. The neural network topology was based on onedimensionalconvolutional layers. The decision-support system,based on the sequential probability ratio test, interpretedthe anomaly generated by the autoencoder. Detection timeand time to failure were the metrics used for performanceevaluation. Anomaly detection was evaluated on five differentsimulated progressions of damage to examine the effectsof driving profile randomness on performance of the anomalydetector.