Effect of current flow on bipolar plate/gas diffusion layer interfacial contact resistance in Proton Exchange Membrane fuel cells (PEMFC)

peer reviewedStainless steel bipolar plates can be excellent alternative to graphite bipolar plates since they display better mechanical properties and the manufacturing procedure is easier and cheaper. However, they are chemically instable in the corrosive environment of PEMFCs, and a thin oxide layer is developed on the plate’s surface. This layer causes a significant increase in the interfacial contact resistance (ICR) between the plates and gas diffusion layers. In an effort to characterize various stainless steel samples, before and after their exposure to the corrosive environment of a PEMFC, the interfacial contact resistance (ICR) between the plates and a commercial gas diffusion layer (GDL) was studied as a function of the pressure applied on the assembly. The ICR was studied in the range of 0-500 N/cm2 of pressure applied to the assembly; the ICR value was determined by means of galvanostatic potentiometry, where a constant current is applied to the assembly and the average value of the potential over time is recorded. The ICR is then calculated, after appropriate simplifications, as: ICR = Rtot = Iapplied / Vmonitored (1) It was observed that, besides the expected exponential reduction of ICR versus pressure, the value of the current applied to the assembly impacted greatly the obtained values for the ICR, irrespective of the applied pressure. This indicates that the observed phenomenon is not caused by any morphological changes on the interface. A possible explanation is that, at higher currents, the temperature increases locally due to ohmic heating, inducing thus changes in the GDL’s resistivity

Solid-state Li metal battery with hybrid electrolyte: An overview of the Horizon Europe SEATBELT project.

International audienceWithin the next decade, new generations of lithium (Li) batteries based on silicon/carbon and Li metal anodes where the conventional flammable liquid electrolyte of the currently commercialized Li-ion device is replaced by a non- flammable solid-one are expected to take over the battery market. Among those, all- solid-state batteries comprising a Li metal anode and a solid-state electrolyte is a target of choice as their properties should overcome all previous battery technologies. Indeed, only all-solid-state Li batteries are expected to fulfil the needed cell gravimetric energy density, cyclability, sustainability and recycling specifications demanded by electromobility and stationary applications. In this context, the EU- funded (Horizon Europe) SEATBELT project will help to pave the road towards a cost-effective, robust all-solid-state Li battery comprising sustainable materials by 2026. SEATBELT intends to achieve the first technological milestone of developingan all-solid-state battery cell meeting the needs of Electric Vehicle (EV) and stationary industry. The low-cost SEATBELT cell is safe-by-design with sustainable and recyclable materials, with the goal to reach high energy densities (>380 Wh/kg) and long cyclability (> 500 cycles) by 2026 in line with the 2030 European targets. Herein, we will present the project and technological strategies that will be developed during the project and the consortium partners. SEATBELT consortium is composed of 14 beneficiary partners and one associated partner spread all over Europe (8 countries). Typically, the battery cells will be produced by low-cost solvent-free extrusion process comprising a combination of innovative materials: thin Li metal, solid hybrid electrolyte, a safe cathode active material without critical materials and thin Al current collector. The cell design being optimized by interface (operando and atomistic modelling) and process (machine learning) methodologies. In addition, in situ imaging instrumentation will be performed to investigate safety properties and mechanical deformation to assess the cell safety in real conditions. An innovative recycling cycle from materials to cell level will be also established

Solid-state Li metal battery with hybrid electrolyte: An overview of the Horizon Europe SEATBELT project.

International audienceWithin the next decade, new generations of lithium (Li) batteries based on silicon/carbon and Li metal anodes where the conventional flammable liquid electrolyte of the currently commercialized Li-ion device is replaced by a non- flammable solid-one are expected to take over the battery market. Among those, all- solid-state batteries comprising a Li metal anode and a solid-state electrolyte is a target of choice as their properties should overcome all previous battery technologies. Indeed, only all-solid-state Li batteries are expected to fulfil the needed cell gravimetric energy density, cyclability, sustainability and recycling specifications demanded by electromobility and stationary applications. In this context, the EU- funded (Horizon Europe) SEATBELT project will help to pave the road towards a cost-effective, robust all-solid-state Li battery comprising sustainable materials by 2026. SEATBELT intends to achieve the first technological milestone of developingan all-solid-state battery cell meeting the needs of Electric Vehicle (EV) and stationary industry. The low-cost SEATBELT cell is safe-by-design with sustainable and recyclable materials, with the goal to reach high energy densities (>380 Wh/kg) and long cyclability (> 500 cycles) by 2026 in line with the 2030 European targets. Herein, we will present the project and technological strategies that will be developed during the project and the consortium partners. SEATBELT consortium is composed of 14 beneficiary partners and one associated partner spread all over Europe (8 countries). Typically, the battery cells will be produced by low-cost solvent-free extrusion process comprising a combination of innovative materials: thin Li metal, solid hybrid electrolyte, a safe cathode active material without critical materials and thin Al current collector. The cell design being optimized by interface (operando and atomistic modelling) and process (machine learning) methodologies. In addition, in situ imaging instrumentation will be performed to investigate safety properties and mechanical deformation to assess the cell safety in real conditions. An innovative recycling cycle from materials to cell level will be also established