Studies related to battery performance and long-term health of commercial Li-ion batteries (LIBs) typically have a fixed temperature parameter. However, commercial LIBs are subject to temperature fluctuations due to their local environment and operating conditions, and these transient temperatures are well known to impact long-term stability. Herein, we demonstrate the adverse effects of temperature shifts, and show that transitioning from low temperature to higher temperature can lead to catastrophic failure within practical temperature ranges experienced by commercial LIBs. We show there exists an Arrhenius relationship between the rate of acoustic attenuation and the magnitude of the temperature shift. A combination of acoustic attenuation, which marks gassing occurrence during cycling, and post mortem chemical analyses provides further mechanistic insight into the Li-rich solid electrolyte interphase (SEI) formation at low temperatures and subsequent reactions with the electrolyte at higher temperatures. Further, several strategies to prevent or mitigate catastrophic failure are introduced. On a broader scale, this research further highlights the importance of temperature and current controls integration into battery management systems (BMS) for both safety and extension of cycle life as battery systems move toward fast charge (>3 C) capability.

Throughout the Caribbean, coral reefs are transitioning from rugose, coral-dominated communities to flat, soft coral-dominated habitats, triggering declines in biodiversity. To help mitigate these losses, artificial structures have been used to re-create substrate complexity and support reef inhabitants. This study used natural and artificial structures to investigate the factors influencing the use of habitat by reef fish. During 2018 and 2019, divers added artificial structures and monitored the fish assemblages associating with both the artificial structures and naturally occurring corals. Overall, there were more fish on natural structures than on artificial structures. While structure shape did not influence fish use, there was a non-significant trend for increased use of larger structures. Fish observations did not differ across a gradient of shallow, complex reefs to deeper, flatter reefs; however, analyses of feeding guilds revealed clearer patterns: herbivores and omnivores were positively associated with low rugosity reefs where macroalgal abundance was higher, whereas invertivores preferred more rugose reefs. These results suggest that as reefs lose structural complexity, fish communities may become dominated by herbivores and omnivores. It also appears that the addition of artificial structures of the type used here may not mitigate the effects of structure loss on reef fish assemblages.

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