TY - JOUR AB - With the lithium-ion technology approaching its intrinsic limit with graphite-based anodes, Li metal is recently receiving renewed interest from the battery community as potential high capacity anode for next-generation rechargeable batteries. In this focus paper, we review the main advances in this field since the first attempts in the mid-1970s. Strategies for enabling reversible cycling and avoiding dendrite growth are thoroughly discussed, including specific applications in all-solid-state (inorganic and polymeric), Lithium–Sulfur (Li–S) and Lithium-O2 (air) batteries. A particular attention is paid to recent developments of these battery technologies and their current state with respect to the 2030 targets of the EU Integrated Strategic Energy Technology Plan (SET-Plan) Action 7. AU - Varzi, Alberto AU - Thanner, Katharina AU - Scipioni, Roberto AU - Di Lecce, Daniele AU - Hassoun, Jusef AU - Dörfler, Susanne AU - Altheus, Holger AU - Kaskel, Stefan AU - Prehal, Christian AU - Freunberger, Stefan Alexander ID - 8361 IS - 12 JF - Journal of Power Sources SN - 0378-7753 TI - Current status and future perspectives of lithium metal batteries VL - 480 ER - TY - JOUR AB - Lithium-ion batteries are in widespread use in electric vehicles and hybrid vehicles. Besides features like energy density, cost, lifetime, and recyclability the safety of a battery system is of prime importance. The separator material impacts all these properties and requires therefore an informed selection. The interplay between the mechanical and electrochemical properties as key selection criteria is investigated. Mechanical properties were investigated using tensile and puncture penetration tests at abuse relevant conditions. To investigate the electrochemical performance in terms of effective conductivity a method based on impedance spectroscopy was introduced. This methodology is applied to evaluate ten commercial separators which allows for a trade-off analysis of mechanical versus electrochemical performance. Based on the results, and in combination with other factors, this offers an effective approach to select suitable separators for automotive applications. AU - Plaimer, Martin AU - Breitfuß, Christoph AU - Sinz, Wolfgang AU - Heindl, Simon F. AU - Ellersdorfer, Christian AU - Steffan, Hermann AU - Wilkening, Martin AU - Hennige, Volker AU - Tatschl, Reinhard AU - Geier, Alexander AU - Schramm, Christian AU - Freunberger, Stefan Alexander ID - 7298 IS - 2 JF - Journal of Power Sources SN - 0378-7753 TI - Evaluating the trade-off between mechanical and electrochemical performance of separators for lithium-ion batteries: Methodology and application VL - 306 ER - TY - JOUR AB - Propagation of performance changes to adjacent cells in polymer electrolyte fuel cell stacks is studied by means of voltage monitoring and local current density measurements in peripheral cells of the stack. A technical fuel cell stack has been modified by implementing two independent reactant and coolant supplies in order to deliberately change the performance of one cell (anomalous cell) and study the coupling phenomena to adjacent cells (coupling cells), while keeping the working conditions of the later cell-group unaltered. Two anomalies are studied: (i) air starvation and (ii) thermal anomaly, in a single anomalous cell in the stack and their coupling to adjacent cells. The results have shown that anomalies inducing considerable changes in the local current density of the anomalous cell (such as air starvation) propagate to adjacent cells affecting their performance. The propagation of local current density changes takes place via the common bipolar plate due to its finite thickness and in-plane conductivity. Consequently, anomalies which do not strongly influence the local current density distribution (such as a thermal anomaly under the studied working conditions) do not propagate to adjacent cells. AU - Santis, Marco AU - Freunberger, Stefan Alexander AU - Papra, Matthias AU - Wokaun, Alexander AU - Büchi, Felix N. ID - 7327 IS - 2 JF - Journal of Power Sources SN - 0378-7753 TI - Experimental investigation of coupling phenomena in polymer electrolyte fuel cell stacks VL - 161 ER -