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Investigations on the effect of flame retardant additives (FRs) on the abuse tolerance of large scale lithium ion battery (LIB) cells (5 Ah) are of high relevance in battery science and industry but rarely performed as they are cost and time consuming. In addition, even though FRs are frequently investigated, their positive effect on the safety properties of larger full LIB cells under abusive condition has not been proven yet. The promising FR (phenoxy) pentafluorocyclotriphosphazene (FPPN) is known to exhibit excellent flame retardant-and electrochemical properties at the same time.Therefore, FPPN is investigated towards abuse tolerance in 5 Ah LIB cells in this study. Calorimetric investigations show that a mass percentage of 5 wt % FPPN mixed to a standard electrolyte, significantly reduces the self-heating rate of 5 Ah cells in the temperature range from 80°C to 110°C. While nail penetration and external short circuit experiments provide no significant difference between standard and FPPN-containing cells, an increased overcharge tolerance and a favorable thermal stability at � 120°C in overcharge and oven experiments could be shown. [a] T. . Nail penetration experiment of 5 Ah cells containing electrolyte with (blue) and without (black) 5 wt % FPPN. a) scheme showing the position of the thermocouples. b) Voltage over time of two cells per additive mixture. Temperature over time of two cells per electrolyte mixture are presented in c) for thermocouple position 1 and in d) for thermocouple position 2. . Overcharge experiment of 5 Ah cells containing electrolyte with (blue) and without (black) 5 wt % FPPN. a) Voltage and b) temperature (position 1) vs. time diagrams of two cells per additive mixture are presented.

For a group of nonionic surfactants with polar head groups synthesized by the copolymerization of ethylene oxide and carbon dioxide, the potential for their application in the foam flotation of microplastic particles was investigated. Their performance was compared to conventional that of nonionic surfactants and correlated with their adsorption behavior at the water–air surface through the maximum-bubble-pressure technique. The carbonate content of the surfactant head groups increased the biodegradability of the surfactants and affected their foaming properties and their performance in the flotation process. Since the inserted carbonate units increased the hydrophilicity of the whole surfactant but decreased the polarity of their headgroups, the number of carbonate units can be considered as an independent tuning parameter for adjusting these surfactants to a particular application. With this feature, the countercurrent trends of the two most important performance indicators, namely the removal rate and enrichment factor, can be resolved.

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